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Enanta Pharmaceuticals, Inc.

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FY2018 Annual Report · Enanta Pharmaceuticals, Inc.
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2018 Annual Report

    Creating Small Molecule Drugs
for Viral Infections and Liver Diseases

 
January 15, 2019

To our Shareholders,

Our goal for the past several years has been to become a leader in the fields of viral infections
and liver diseases through investing in, and diversifying into, treatments for diseases in these
fields that have significant unmet need and market opportunity. I’m proud to say that we have

made significant progress toward this goal and I’m happy to provide you with this update.

Enanta’s successful hepatitis C virus (HCV) collaboration with AbbVie continues to provide us the royalty funding
to advance our wholly-owned research and development programs in respiratory syncytial virus (RSV),
non-alcoholic steatohepatitis (NASH), primary biliary cholangitis (PBC), and hepatitis B virus (HBV). In our 2018
fiscal year, which began shortly after the launch of AbbVie’s MAVYRET™/MAVIRET™ HCV regimen, Enanta
received approximately $192 million in AbbVie royalties. And by the end of 2018, MAVYRET™/MAVIRET™ had
become the best-selling HCV treatment in the world.

Our clinical development programs are advancing, and we have many milestones to look forward to during
2019. Our most advanced development program is for RSV, where a Phase 2a human challenge study in healthy
adults inoculated with RSV is ongoing and we expect top-line data in mid-2019. This study is investigating
EDP-938, our non-fusion inhibitor candidate targeting the N-Protein in the RSV virus, and the only N-inhibitor in
clinical development today. RSV represents an opportunity to work in an area where we have a differentiated
approach, with positive early clinical data and limited competition, and where there is no therapeutic treatment
available.

Our NASH and PBC programs continue to enroll for our two Phase 2 clinical studies with EDP-305, our FXR
agonist candidate. Enrollment in the 12-week Phase 2a NASH trial is expected to conclude in the first quarter of
2019 allowing Enanta to report preliminary top line data in the third quarter of 2019. We also continue to
advance discovery and preclinical development of follow-on FXR compounds and non-FXR compounds for
NASH.

Lastly, I am very excited about the selection of EDP-514 as our first development candidate from our HBV
program. EDP-514 is a core inhibitor, also referred to as a capsid assembly modulator or a core protein allosteric
modulator. This is a new class of HBV inhibitors that can disrupt the assembly and replication of the virus at
multiple steps in the viral lifecycle. Based on our preclinical data, we believe EDP-514 has best-in-class potential
for the core inhibitor mechanism and we expect to initiate a Phase 1 study this year.

Enanta has made significant advances the past year with more to look forward to in 2019. I would like to thank
our employees for all their efforts and you, our shareholders, for your support. I look forward to updating you
on our progress throughout the coming year.

Sincerely,

Jay R. Luly Ph.D.
President and Chief Executive Officer

UNITED STATES 
SECURITIES AND EXCHANGE COMMISSION 
Washington, D.C. 20549 

Form 10-K 

⌧ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES 

EXCHANGE ACT OF 1934 

For the fiscal year ended September 30, 2018
OR 

(cid:4) TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES 

EXCHANGE ACT OF 1934 

Commission File Number 001-35839 

ENANTA PHARMACEUTICALS, INC. 

(Exact name of registrant as specified in its charter) 

DELAWARE
(State or other jurisdiction of
incorporation or organization)

2834
(Primary Standard Industrial
Classification Code Number)

04-3205099
(I.R.S. Employer
Identification Number)

500 Arsenal Street 
Watertown, Massachusetts 02472 
(617) 607-0800 
(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices) 
Securities registered pursuant to Section 12(b) of the Act: 

Title of each class:
Common Stock, $0.01 Par Value

Name of each exchange on which registered:
The NASDAQ Stock Market LLC (NASDAQ Global Select Market)

Securities registered pursuant to Section 12(g) of the Act: None 

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes  (cid:4)    No  ⌧ 
Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.    Yes  (cid:4)    No  ⌧ 
Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 
1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing 
requirements for the past 90 days:    Yes  ⌧    No  (cid:4) 

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 

405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such 
files):    Yes  ⌧    No  (cid:4)

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, 

to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any 
amendment to this Form 10-K.    ⌧ 

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or 

an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth 
company” in Rule 12b-2 of the Exchange Act: 
Large accelerated filer ⌧
(cid:4)  
Non-accelerated filer
Emerging growth company (cid:4)

Accelerated filer
Smaller reporting company

(cid:4)
(cid:4)

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with 

any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.   (cid:4)

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act):    Yes  (cid:4)    No   ⌧ 
The aggregate market value of the registrant’s common stock held by non-affiliates of the registrant as of the last business day of the registrant’s 
most recently completed second fiscal quarter, March 31, 2018, based on the last reported sale price of the registrant’s common stock of $80.91 per share 
was $1,280,474,378. The number of shares of the registrant’s Common Stock, $0.01 par value, outstanding as of November 1, 2018 was 19,423,949 shares. 
DOCUMENTS INCORPORATED BY REFERENCE 

Portions of the registrant’s Definitive Proxy Statement for its 2018 Annual Meeting of Stockholders scheduled to be held on February 28, 2019, 

which Definitive Proxy will be filed with the Securities and Exchange Commission not later than 120 days after the registrant’s fiscal year end of 
September 30, 2018 are incorporated by reference into Part III of this Form 10-K. 

 
As used in this Form 10-K, “Enanta,” “the Company,” “we,” “our,” and “us” refer to Enanta Pharmaceuticals, Inc., 
and “MAVYRET/MAVIRET” refers to AbbVie’s HCV regimen consisting of tablets of glecaprevir/pibrentasvir, 
except where the context otherwise requires or as otherwise indicated. MAVYRET™, MAVIRET™, VIEKIRA 
PAK™, TECHNIVIE™, VIEKIRAX™, VIEKIRA XR™ and, EXVIERA™ are trademarks of AbbVie, Inc.

NOTE REGARDING FORWARD LOOKING STATEMENTS 

This Annual Report on Form 10-K contains forward-looking statements concerning our business, operations and 
financial performance and condition, as well as our plans, objectives and expectations for our business operations 
and financial performance and condition. Any statements contained herein that are not statements of historical facts 
may be deemed to be forward-looking statements. In some cases, you can identify forward-looking statements by 
terminology such as “aim,” “anticipate,” “assume,” “believe,” “contemplate,” “continue,” “could,” “due,” 
“estimate,” “expect,” “goal,” “intend,” “may,” “objective,” “plan,” “predict,” “potential,” “positioned,” “seek,” 
“should,” “target,” “will,” “would,” and other similar expressions that are predictions of or indicate future events 
and future trends, or the negative of these terms or other comparable terminology. These forward-looking statements 
include, but are not limited to, statements about overall trends, royalty revenue trends, research and clinical 
development plans, liquidity and capital needs and other statements of expectations, beliefs, future plans and 
strategies, anticipated events or trends and similar expressions. These forward-looking statements are based on our 
management’s current expectations, estimates, forecasts and projections about our business and the industry in 
which we operate and our management’s beliefs and assumptions. These forward-looking statements are not 
guarantees of future performance or development and involve known and unknown risks, uncertainties and other 
factors that are in some cases beyond our control. As a result, any or all of our forward-looking statements in this 
Annual Report on Form 10-K may turn out to be inaccurate. Factors that may cause actual results to differ materially 
from current expectations include, among other things, those listed under “Risk Factors” and discussed elsewhere in 
this Annual Report on Form 10-K. These forward-looking statements speak only as of the date of this Annual Report 
on Form 10-K. Except as required by law, we assume no obligation to update or revise these forward-looking 
statements for any reason, even if new information becomes available in the future. You should, however, review 
the factors and risks we describe in the reports we will file from time to time with the SEC after the date of this 
Annual Report on Form 10-K. 

 
ENANTA PHARMACEUTICALS, INC. 

ANNUAL REPORT ON FORM 10-K 

For the year ended September 30, 2018

INDEX 

Item No.

Page

PART I
Business ....................................................................................................................................................
Risk Factors...............................................................................................................................................
Unresolved Staff Comments .....................................................................................................................
Properties ..................................................................................................................................................
Legal Proceedings .....................................................................................................................................
Mine Safety Disclosures ...........................................................................................................................

1.
1A.
1B.
2.
3.
4.

PART II

5.

Market for the Company’s Common Equity, Related Stockholder Matters and Issuer Purchases of 
Equity Securities .......................................................................................................................................
Selected Consolidated Financial Data.......................................................................................................
6.
7.
Management’s Discussion and Analysis of Financial Condition and Results of Operations ...................
7A. Quantitative and Qualitative Disclosures about Market Risk ...................................................................
Consolidated Financial Statements and Supplementary Data...................................................................
8.
Changes in and Disagreements with Accountants on Accounting and Financial Disclosure...................
9.
Controls and Procedures ...........................................................................................................................
9A.
Other Information .....................................................................................................................................
9B.

10.
11.
12.
13.
14.

15.
16.

PART III
Directors, Executive Officers and Corporate Governance........................................................................
Executive Compensation...........................................................................................................................
Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters.
Certain Relationships and Related Transactions, and Director Independence .........................................
Principal Accounting Fees and Services ...................................................................................................

PART IV
Exhibits, Financial Statement Schedules ..................................................................................................
Form 10-K Summary ................................................................................................................................
Signatures..................................................................................................................................................

1
26
54
54
54
54

55
57
58
71
71
71
72
72

73
73
73
74
74

74
76
77

 
 
 
 
 
 
ITEM 1.

BUSINESS 

Overview 

PART I

BUSINESS 

We are a biotechnology company that uses our robust, chemistry-driven approach and drug discovery capabilities to 
create small molecule drugs primarily for the treatment of viral infections and liver diseases. We discovered 
glecaprevir, the second of two protease inhibitors discovered and developed through our collaboration with AbbVie 
for the treatment of chronic hepatitis C virus, or HCV. Glecaprevir is co-formulated as part of AbbVie’s newest 
direct-acting antiviral (DAA) combination and marketed under the tradenames MAVYRET™ (U.S.) or 
MAVIRET™ (ex-U.S.) (glecaprevir/pibrentasvir). Our royalties from our AbbVie collaboration and our existing 
financial resources provide us funding to support our wholly-owned research and development programs, which are 
currently focused on the following disease targets: 

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(cid:129)

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respiratory syncytial virus, or RSV, the most common cause of bronchiolitis and pneumonia in children 
under one year of age in the U.S., resulting in an estimated 57,000 to 125,000 U.S. hospitalizations each 
year; 

non-alcoholic steatohepatitis, or NASH, a liver disease estimated to affect approximately 1.5% to 6.5% 
of the population in the developed world (which translates to approximately 5 to 20 million individuals 
in the U.S. alone);

primary biliary cholangitis, or PBC, a chronic liver disease that slowly destroys bile ducts in the liver, 
which affects an estimated 17,000 individuals in the U.S.; and

hepatitis B virus, or HBV, the most prevalent chronic hepatitis, which is estimated to affect 
approximately 250 million individuals worldwide.

We had $325.1 million in cash, cash equivalents and marketable securities at September 30, 2018. In fiscal 2018, we 
earned $191.6 million in per-product royalties on AbbVie’s net sales of its HCV regimens and we earned the 
remaining $15.0 million milestone payment from AbbVie upon reimbursement approval for MAVIRET™ in Japan. 
We expect our existing financial resources and future royalties from our AbbVie collaboration will allow us to 
continue to fund our wholly-owned research and development programs for the foreseeable future.

Our Wholly-Owned Programs 

Our wholly-owned research and development programs are in virology, namely RSV and HBV, and in liver disease 
(non-virology), namely NASH and PBC: 

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RSV: We discovered EDP-938, a potent N-protein inhibitor of activity of both major subgroups of RSV, 
referred to as RSV-A and RSV-B, and have tested it as our first clinical candidate for RSV. We believe 
EDP-938 is differentiated from fusion inhibitors currently in development for RSV because N-protein 
inhibitors directly target the viral replication process of RSV and have demonstrated high barriers to 
resistance against RSV in vitro. 

o

In our fiscal 2018, we completed a Phase 1 clinical study demonstrating that EDP-938 was 
generally safe and well tolerated over a broad range of single and multiple doses with good 
pharmacokinetic data.

o We initiated a Phase 2a challenge study of EDP-938 in October 2018. The challenge study will 
test the effect of EDP-938 on healthy volunteers who will be infected with RSV and then treated 
with EDP-938 or placebo during the course of the study. Primary and secondary outcome 
measures include changes in viral load measurements and change of baseline symptoms.

o

Preclinical data demonstrated that EDP-938 is a potent inhibitor of both RSV-A and RSV-B 
activity, maintaining antiviral activity post-infection while presenting a high barrier to 
resistance in vitro.

1

(cid:129)

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NASH and PBC: We are working on multiple compounds that selectively bind to and activate the 
farnesoid X receptor, or FXR. We plan to develop these compounds, referred to as FXR agonists, for 
use in the treatment of NASH and PBC, both of which are liver diseases with very few therapeutic 
options. Our lead FXR agonist, EDP-305, represents a new class of FXR agonists designed to take 
advantage of increased binding interactions with the receptor. We believe this class is significantly 
different from other FXR agonists in clinical development.

o

In October 2017, we announced results of a Phase 1a/b clinical study of EDP-305, which was 
generally safe and well tolerated over a broad range of single and multiple doses with 
pharmacokinetic data supporting once daily oral dosing. Additional data from this study were also 
presented at the 2018 NASH-TAG conference and the International Liver CongressTM (ILC) 2018. 
The study included 98 healthy volunteer subjects, or HV subjects, and 48 subjects who were 
obese and with or without pre-diabetes or type 2 diabetes, whom we refer to as subjects with 
presumptive non-alcoholic fatty liver disease, or PN subjects.

o We have presented data at the 2017 and 2018 annual meetings of the American Association for 

the Study of Liver Diseases (AASLD), the 2017 and 2018 NASH-TAG conferences and the 2017 
and 2018 ILC conferences that demonstrated that EDP-305 is a highly selective FXR agonist and 
shows more potent activity in a variety of in vitro and in vivo NASH models compared to the most 
advanced NASH candidate in development today, obeticholic acid, or OCA.

o We initiated a Phase 2 clinical study, known as ARGON-1, of EDP-305 in NASH patients and a 

Phase 2 clinical study, known as INTREPID, of EDP-305 in PBC patients. 

o

o

EDP-305 has been granted Fast Track designation by the U.S. Food and Drug Administration 
(FDA) for the treatment of NASH patients with liver fibrosis and separately for the treatment of 
PBC.

In addition, we are pursuing research in other classes of FXR agonists as well as other 
mechanisms that may provide therapeutic benefit in NASH, any of which could be used in 
combination therapies for NASH.

HBV: We also have a program to discover and develop new chemical entities for the treatment of HBV. 
Our initial focus is on core inhibitors, a mechanism with early clinical validation. In November 2018, 
we announced our first clinical candidate for HBV. EDP-514 is an HBV core inhibitor, also known as a 
core protein allosteric modulator or capsid assembly modulator. 

o

o

EDP-514 was selected from our lead class of HBV compounds that are characterized by potent 
antiviral activity.   In vitro, they are capable of preventing the establishment of cccDNA, are pan-
genotypic, are active against known nucleos(t)ide resistant mutants, and are additive to synergistic 
with nucleoside analogs and other core inhibitors.  Members of this class have also demonstrated 
excellent reduction in HBV titers in a chimeric mouse model with human liver cells.

In addition, we are also seeking patent protection and conducting preclinical experiments with 
compounds we have discovered that use other mechanisms to target HBV. We believe that it may 
be necessary to utilize more than one compound/mechanism for the treatment of HBV and 
therefore we are pursuing multiple approaches. 

We have utilized our internal chemistry and drug discovery capabilities to generate all of our development-stage 
programs.

2

Our Out-Licensed Products 

(cid:129)

(cid:129)

Through our Collaborative Development and License Agreement with AbbVie, we have developed and 
out-licensed to AbbVie two protease inhibitor compounds that have been clinically tested, 
manufactured, and commercialized by AbbVie. To date, we have earned all $330.0 million milestone 
payments under the agreement related to clinical development and commercialization regulatory 
approvals of these regimens in major markets.

Glecaprevir: Glecaprevir is the protease inhibitor we discovered that was developed by AbbVie in a 
fixed-dose combination with its NS5A inhibitor, pibrentasvir, for the treatment of HCV. This 
combination, currently marketed under the brand name MAVYRET™ (U.S.) and MAVIRET™ (ex-
U.S.) and referred to in this report as MAVYRET/MAVIRET, is a novel, once daily, all oral, fixed-
dose, ribavirin-free treatment for HCV genotypes 1-6, or GT1-6, which is referred to as being pan-
genotypic. In the U.S., EU and Japan it was approved as an 8-week treatment for patients without 
cirrhosis and new to treatment. Today, these patients are estimated to represent the majority of HCV 
patients in developed country markets.

Since August 2017, substantially all of our royalty revenue has been derived from AbbVie’s net sales of 
MAVYRET/MAVIRET. Our ongoing royalty revenues from this regimen consist of annually tiered, 
double-digit, per-product royalties (see Note 7 in Notes to Consolidated Financial Statements) on 50% 
of the calendar year net sales of the 2-DAA glecaprevir/pibrentasvir combination in 
MAVYRET/MAVIRET. These royalties are calculated separately from the royalties on AbbVie’s 
paritaprevir-containing regimens.

Paritaprevir: Paritaprevir is the protease inhibitor contained in AbbVie’s initial HCV treatment regimens 
sold under the tradenames VIEKIRAX® (ex-U.S.) and VIEKIRA PAK® (U.S.) (paritaprevir/ritonavir/ 
ombitasvir/dasabuvir). These regimens are no longer being actively marketed in markets where 
MAVYRET/MAVIRET is approved and reimbursed. AbbVie’s paritaprevir-containing regimens were 
first approved and sold in the U.S. in December 2014. Through our 2017 fiscal year end, our royalty 
revenues were generated substantially through worldwide net sales of these regimens. 

Our Strategy 

Our primary objective is to become a leader in the field of viral infections and liver diseases in order to 
provide new treatments for patients with unmet medical needs. Our focus is on antiviral targets for 
viruses such as RSV and HBV as well as liver diseases, such as NASH and PBC. All of these disease 
areas involve significant market opportunities and have attracted the research and development efforts 
of many competitors. Our strategy includes the following key elements: 

Develop novel treatment options for RSV, NASH, PBC and HBV. We have potential candidates in 
clinical development for RSV, NASH and PBC. We completed a Phase 1 clinical study of our lead RSV 
candidate, EDP-938, and have initiated a Phase 2a challenge study in RSV in October 2018. We also 
completed a Phase 1 a/b clinical study of EDP-305, our lead FXR agonist, and initiated two Phase 2 
clinical studies of this compound during fiscal 2018 – one in NASH patients and one in PBC patients. In 
addition, we recently selected a development candidate for HBV, EDP-514, which we plan to test in a 
Phase 1 a/b clinical study initiating in 2019.

Invest in research and development of additional product candidates in RSV, NASH/PBC and HBV. We 
are continuing to invest significant resources in our RSV, NASH, PBC and HBV research programs in 
an effort to identify and advance additional novel compounds that have the potential to address 
significant unmet medical needs in these disease areas. We may clinically explore other diseases where 
our assets could play a role. In addition, we may seek to augment our product candidate pipeline 
through the acquisition or in-licensing of external assets and/or technologies in one or more of our 
disease areas of focus. 

Use our existing resources and future cash flow from our AbbVie collaboration to fund our research 
and development activities. Our existing financial resources and future royalty payments from our 
AbbVie collaboration will provide us substantial resources to fund our research and development 
programs for the foreseeable future. These resources will allow us to continue to advance compounds in 
clinical development as well as to progress the most promising candidates at least through proof-of-

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3

concept for further development as a monotherapy or in combinations with other therapeutic agents 
when we believe such combinations will provide the most promising opportunities. 

(cid:129)

Collaborate, where and when appropriate, with pharmaceutical partners to create combination 
therapies and accelerate the development and commercialization of our proprietary compounds. We are 
prepared to join forces, where and when appropriate, with collaborators with compounds targeting other 
mechanisms of action in diseases such as NASH and HBV, where there is the potential for better 
treatments with combination therapies. Our decisions regarding our proprietary programs will be based 
on the results of our early phase clinical studies and the potential for combinations with one or more 
drugs targeting other mechanisms of action in these diseases. 

Our Research and Development Pipeline

The following table summarizes our product development pipeline in our virology and liver disease programs: 

Our RSV Program 

Background and Overview of RSV 

Respiratory syncytial virus, or RSV, is a virus that infects the lungs and represents a serious unmet medical need in 
infants and children, as well as immune-compromised individuals and the elderly. RSV is the most common cause 
of bronchiolitis (inflammation of the small airways in the lung) and pneumonia in children under 1 year of age in the 
United States. Each year, 57,000 to 125,000 patients in the U.S. are hospitalized due to RSV infection. In one large 
U.S.-based study, RSV infection in children was associated with 20% of hospitalizations, 18% of emergency 

4

department visits, and 15% of pediatric office visits for acute respiratory infections in the November-April 
timeframe. Though a prophylactic monoclonal antibody-based treatment is available for infants considered at high 
risk for RSV infection, this study found that most young children affected by RSV infection were previously 
healthy, and thus would not normally be considered for prophylaxis. There are currently no safe and effective 
therapies for already established RSV infection. Several companies are seeking new antiviral treatments for RSV 
infection in adult and pediatric settings and others are developing vaccines.

Scientific Background

RSV is a single-stranded, negative-sense RNA virus. The RSV genome consists of ten genes that encode for 11 
proteins, namely NS1, NS2, N, P, M, SH, G, F, M2-1, M2-2, and L.  The F and G proteins are the predominant 
target proteins for RSV vaccines. Similarly, small molecule therapeutics have focused primarily on the F (or fusion) 
protein, while some efforts have targeted the N and L proteins. There are two major subgroups of RSV, designated 
RSV-A and RSV-B, each of which contains numerous genotypes. Both groups are viewed as capable of causing 
RSV infections that can result in hospitalization.

EDP-938 and Our Approach to the Treatment of RSV 

While a number of companies are developing potential approaches geared towards the F protein (or fusion protein, 
responsible for mediating viral entry of RSV into host cells), we are focused on other mechanisms, such as the N-
protein pathway, that target the replication process of RSV. It is possible that N-protein inhibitors may also be 
effective treatments at later stages of infection. We are currently the only company with an N inhibitor in clinical 
development.

Through our internal chemistry efforts, we identified a clinical candidate, EDP-938. During preclinical studies, 
EDP-938 demonstrated a greater than 4-log reduction in viral load in an animal model challenged with RSV. 
Further, EDP-938 maintained antiviral potency across all clinical isolates tested in vitro, as well as virus that was 
resistant to fusion inhibitors. The compound inhibited RSV at a post-entry replication step and maintained its 
activity in vitro when given 24 hours post infection. In addition, combination studies of EDP-938 with other types of 
RSV inhibitors, such as fusion inhibitors, showed synergistic antiviral effects.

During fiscal 2018, we initiated and completed a Phase 1 clinical study of EDP-938. On November 1, 2018, we 
presented full Phase 1 data at the 11th International Respiratory Syncytial Virus Symposium. The Phase 1, 
randomized, double-blind, placebo (PBO)-controlled, first-in-human study was conducted to evaluate the safety, 
tolerability, and pharmacokinetics (PK) of single- and multiple- (7 days) ascending doses (SAD: 50 - 800 mg and 
MAD: 100 - 600 mg once daily and 300 mg twice daily) and food effect (FE) of EDP-938 in healthy subjects. In the 
SAD phase, 50 subjects [EDP-938 (n=38) and PBO (n=12)] were enrolled in 6 dose cohorts; in the MAD phase, 40 
subjects [EDP-938 (n=30) and PBO (n=10)] were enrolled in 5 dose cohorts. Overall, no safety concerns were 
reported in 68 healthy subjects receiving a broad range of single and multiple doses of EDP-938. Headache was the 
most frequently reported AE during the SAD and MAD phases. There were no SAEs, and AEs were of mild 
intensity, with none leading to study drug discontinuation. EDP-938 was rapidly absorbed and exposure increased 
with increasing single and multiple dosing, resulting in a PK profile suitable for once or twice daily oral dosing 
regardless of food. In the MAD phase, half-life ranged from 12.9 to 17.6 hours, and at doses comparable to those 
under study in the Phase 2a trial, and mean trough levels were approximately 30x higher than the EC90 of EDP-938 
against RSV-infected human cells.

5

Based on the results above, we initiated a Phase 2a challenge study of EDP-938 in October 2018. In this 
randomized, double-blind, placebo-controlled, human challenge study, up to 114 healthy adult subjects will be 
randomized into 1 of 3 arms (1:1:1) and will be dosed for 5 days. All subjects will be infected with RSV-A 
Memphis 37b virus, and approximately 76 subjects will receive EDP-938 and 38 subjects will receive placebo. Arm 
1 will receive placebo, Arm 2 will receive a single 500 mg loading dose of EDP-938 followed by 300 mg doses 
twice daily, and Arm 3 will receive a 600 mg dose daily. 

Our FXR Program in NASH and PBC 

Background and Overview of NASH and PBC 

Non-alcoholic fatty liver disease, or NAFLD, is the accumulation of excessive fat in liver cells in the form of 
triglycerides, a process known as hepatic steatosis, that is not associated with alcohol abuse. It is normal for the liver 
to contain some fat. However, if more than 5%-10% of the liver’s weight is fat, then it is called a fatty liver. A 
subgroup of NAFLD patients have liver cell injury and inflammation (steatohepatitis) in addition to excessive fat. 
Progression of this condition leads to non-alcoholic steatohepatitis, or NASH. Patients with NASH can develop 
fibrosis, a fibrous scarring of the liver, and ultimately cirrhosis of the liver. Typically scored on a scale of 1-4, also 
referred to as F1-F4, fibrosis in its earlier stages has been shown to be reversible, but in its most advanced stage 
results in cirrhosis, which is understood to be a more advanced, irreversible scarring of the liver, potentially leading 
to hepatocellular carcinoma (HCC) or requiring a liver transplant. NASH is widely considered to be the liver 
expression of metabolic diseases related to type 2 diabetes, insulin resistance, obesity, hyperlipidemia and 
hypertension.   

Stages of Liver Injury

According to the World Gastroenterology Organization Global Guidelines 2014, NASH is an increasingly common 
chronic liver disease with worldwide distribution that is closely associated with diabetes and obesity, which have 
both reached epidemic proportions. It is estimated that there are at least 1.46 billion obese adults worldwide. 
Approximately 3%-5% of individuals in the U.S. are estimated to have progressed to NASH, 20% of whom are 
likely to develop cirrhosis. NASH and NAFLD are now considered the number one cause of liver disease in Western 
countries.

Currently, there are no approved treatments for NASH. While patients presenting with NASH are counseled on 
lifestyle modifications, new effective treatments are urgently needed, particularly in the setting of advanced fibrosis 
and cirrhosis. We expect significant competition from other companies in the development of treatments for NASH 
and related conditions. Currently, Intercept Pharmaceuticals, Genfit, Gilead and Allergan (Tobira) have compounds 
in one or more Phase 3 trials in NASH. In addition, many Phase 2 and earlier stage studies of other classes of 
compounds are underway by various companies. 

6

Primary biliary cholangitis (formerly known as primary biliary cirrhosis), or PBC, is a chronic, or long-term, disease 
of the liver that slowly destroys the medium-sized bile ducts within the liver. Bile is a digestive liquid that is made 
in the liver. It travels through the bile ducts to the small intestine, where it helps digest fats and absorb fatty 
vitamins. In patients with PBC, the bile ducts are destroyed by inflammation. This causes bile to remain in the liver, 
where gradual injury damages liver cells and causes cirrhosis, or scarring of the liver. As cirrhosis progresses and 
the amount of scar tissue in the liver increases, the liver loses its ability to function, leading to potential liver failure, 
liver transplantation or hepatocellular carcinoma. While PBC is a relatively rare disease (the incidence in Europe, 
North America, Asia and Australia ranges from 0.33-5.8 cases per 100,000, and is 10 times more common in women 
than in men), it remains one of the major causes of liver failure and/or the need for liver transplant.

Agonists of the farnesoid X receptor, referred to as FXR agonists, have shown promising activity in many 
preclinical models of liver disease. One FXR agonist, obeticholic acid, or OCA (brand name Ocaliva ®), which was 
approved by the FDA in May 2016 for the treatment of PBC, has already demonstrated favorable clinical results in 
NASH. We believe that new FXR agonists may provide substantial therapeutic benefit in NASH and PBC and may 
overcome some of the potential shortcomings of OCA, including limited effects on resolution of NASH, elevation of 
low-density lipoprotein, or LDL, and itching, also called pruritis. 

Scientific Background 

FXR is a nuclear hormone receptor that functions to modulate gene expression in response to various metabolic 
stimuli. FXRs are expressed at high levels in the liver and intestine. Bile acids have been identified as important 
physiological ligands for FXRs, able to bind and activate the receptor. The downstream gene modulation resulting 
from bile acid engagement of FXRs not only contribute to the regulation of bile acid synthesis and metabolism, but 
is also involved in a number of other metabolic processes, in particular lipid metabolism. More recently, it has been 
discovered that bile acids, via FXR, are able to promote insulin sensitivity and decrease lipid synthesis in the liver. 
In addition, studies have shown that bile acid-dependent FXR activation is able to provide beneficial effects on 
fibrosis in the liver as well. For these reasons, FXR is considered to be a viable target for NASH. Recent Phase 2b 
trials with OCA, a synthetic analog of natural bile acids known to activate FXR, demonstrated efficacy in NASH 
patients. In PBC, improved outcomes would be expected due to the reduction of bile acid synthesis by activation of 
FXR. OCA demonstrated efficacy in a Phase 3 trial in PBC, which was the basis for its conditional approval in the 
U.S. in May 2016 for the treatment of PBC in combination with first line therapy ursodeoxycholic acid (UDCA) in 
adults with an inadequate response to UDCA, or as monotherapy in adults unable to tolerate UDCA. 

EDP-305 and Our Approach to the Treatment of NASH and PBC 

Even though there has been clinical validation demonstrated by the FXR agonist, OCA, we believe that there is an 
opportunity for the development of a treatment that shows improvements in potency and efficacy and reductions in 
potential safety liabilities for the treatment of NASH and PBC. Using our strong chemistry capabilities, we have 
undertaken the discovery and development of new FXR agonists that we believe may provide substantial 
improvements over the FXR agonists currently in advanced clinical development.   

EDP-305, our lead FXR agonist candidate, represents a new class of FXR agonists that has been designed to take 
advantage of increased binding interactions with the receptor. Further, this non-bile acid class contains steroidal and 
non-steroidal components and does not contain the carboxylic acid group that can lead to the formation of taurine 
and glycine conjugates normally associated with bile acids, which may also be present in other classes of FXR 
agonists.

We reported the results of our Phase 1 a/b clinical study of EDP-305 in October 2017. Our double-blind, placebo-
controlled Phase 1 study was designed to evaluate the safety, tolerability and pharmacokinetics of single ascending 
doses, or SAD, and multiple ascending doses, or MAD, of EDP-305 in adult healthy volunteer subjects, or HV 
subjects, and subjects with presumptive NAFLD, or PN subjects. By presumptive NAFLD, we mean adults who are 
obese, with or without pre-diabetes or type 2 diabetes. 

7

In this Phase 1 study, EDP-305 was shown to be generally safe and well tolerated over a broad range of single and 
multiple doses with pharmacokinetic, or PK, data supporting once daily oral dosing. EDP-305 exhibited strong 
engagement of the FXR receptor as evidenced by increased FGF19 levels and reduced C4 levels, which are proteins 
that can be monitored as downstream markers indicating FXR activity. The results of the study support the ability to 
administer EDP-305 in future trials at doses that neither elicit clinically significant changes in lipids nor result in 
pruritus.

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A total of 146 subjects received at least one dose of EDP-305 (n=110) or placebo (n=36) including 50 
HV subjects in the SAD phases of the study and 96 (48 HV and 48 PN) subjects in the MAD phases of 
the study. Overall, mean body mass index, or BMI, in the PN cohort was 32 (29, 35). SAD had 6 
cohorts at doses of 1, 5, 10, 20, 40 and 80 mg EDP-305/placebo, and MAD had 6 cohorts at doses of 
0.5, 1, 2.5, 5, 10 and 20 mg EDP-305/placebo for 14 days.

Strong FXR target engagement was demonstrated, with doses of EDP-305 > 1 mg increasing FGF19 
and reducing C4 in all subjects, while PN subjects were even more sensitive with significant effects also 
observed in both parameters at the lowest multiple doses of 0.5 and 1 mg. 

No serious adverse events (SAEs) were reported, and EDP-305 was generally well tolerated at all doses 
tested.

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Treatment-emergent adverse events occurring in ≥ 2 EDP-305 treated subjects in MAD cohorts 
were: headache and pruritus in HV subjects, and constipation and pruritus in PN subjects. 

Of the cases of pruritus noted (9% for EDP-305, 3% in placebo), the majority were mild or 
moderate and occurred at multiple doses of 20 mg, with no cases below 10mg. Notably, EDP-305 
demonstrated potent engagement of the FXR receptor across the lower dose range where there 
was no pruritus.  

Two subjects discontinued treatment in the MAD phase at the 20 mg dose level, one for a 
transient grade 2 elevation of ALT/AST liver enzymes, and one for moderate pruritus. 

No dose-related changes in lipids were observed in HV subjects at any doses; and no dose-related 
changes in lipids were observed in PN subjects except for reductions of total cholesterol and high-
density lipoprotein, or HDL, cholesterol at the multiple 20mg dose, with no concomitant increase in 
low-density lipoprotein, or LDL, cholesterol.

We initiated two Phase 2 dose-ranging studies in fiscal 2018 – one in PBC patients, known as INTREPID, and one 
in NASH patients, known as ARGON-1. Both studies are 12-week, dose ranging, randomized, double-blind, 
placebo-controlled trials. The main goals of the studies will be to evaluate safety, tolerability, PK, and efficacy 
based on reduction in the level of key enzymes in subjects’ plasma (alanine aminotransferase, or ALT, reduction in 
NASH and alkaline phosphatase, or ALP, reduction in PBC). A new tablet formulation will be utilized in these 
Phase 2 studies at strengths of 1mg and 2.5mgs (tablet formulation yields ~ 2X greater exposure than the suspension 
formulation used in the Phase 1 study.

Our HBV Program 

Background and Overview of HBV 

Hepatitis B virus, or HBV, can cause potentially life-threatening liver infection. The virus is transmitted through 
contact with the blood or other bodily fluids of an infected person. It is estimated that approximately 250 million 
people worldwide are chronically infected, and 15-25% of patients with chronic HBV infection develop chronic 
liver disease, including cirrhosis, liver cancer, or liver decompensation. It is also estimated that more than 885,000 
people worldwide died in 2015 due to complications of HBV. Estimates for the total number of persons chronically 
infected with HBV in the U.S. vary but generally range between 0.5 million and 2.0 million. Combining U.S., Japan, 
and major EU populations, estimates of HBV prevalence have been as high as 4.8 million.

8

Current approaches to treatment include interferon therapy and/or inhibitors of HBV reverse transcriptase, the 
enzyme responsible for viral DNA synthesis, which is necessary for HBV replication. Treatment with interferon 
offers modest cure rates, and is accompanied by serious side effects, including flu-like symptoms, fatigue, headache 
and nausea. Reverse transcriptase inhibitors can be very effective at suppressing the virus but often require lifelong 
therapy and rarely result in full eradication of the virus from the liver. New treatments that can provide functional 
cures to chronically-infected patients are urgently needed. 

Scientific Background

HBV is a partially double-stranded DNA virus with a complex life cycle. There are multiple mechanisms associated 
with HBV replication that could potentially be targeted with new drugs, and combination approaches may ultimately 
provide the most effective therapy for HBV. Mechanisms under study for HBV include:

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Entry inhibitors that interfere with the initial binding of HBV to hepatocytes, thus preventing new 
infection from occurring. 

Inhibitors of covalently closed circular DNA, or cccDNA, the template for HBV replication, which are 
in early stages of development. Most of these inhibitors act in an indirect manner, such as preventing 
formation of cccDNA or silencing its transcription. 

RNA silencing of gene expression, another prominent approach in the search for HBV inhibitors, which 
utilizes small interfering RNA’s (siRNA’s). This mechanism has the potential to significantly reduce 
HBV RNA, HBV DNA, and HBV protein levels. 

Inhibition of the hepatitis B core protein, which plays a critical role in viral replication, intracellular 
trafficking, and maintenance of chronic infections. Using this core inhibitor mechanism (also known as 
capsid assembly inhibitor or core protein allosteric modifier), some initial data shows reduction in HBV 
DNA and HBV RNA in early clinical trials. 

The surface antigen of HBV, or HBsAg, which is the main envelope protein of the virus and, another 
target in the HBV life cycle. HBsAg is critical to ongoing infection, and loss of serum HBsAg is 
associated with a functional cure of HBV, characterized by no inflammation, normal liver enzymes, and 
normal liver biopsy. Therefore, HBsAg is the target of several therapeutic approaches, including indirect 
ones such as siRNA mentioned above, but also specific approaches including the inhibition of HBsAg 
release. 

The modulators of the human immune system, or immunomodulators, another major mechanism being 
researched. HBV has evolved to evade the natural host immune mechanisms that normally would clear a 
viral infection, thus approaches that can augment the immune response are being actively pursued.  In 
fact, interferon has been used for the treatment of HBV for decades and while it can induce a functional 
cure, the cure is only seen in a small percentage of patients and the treatment is generally not well 
tolerated. More targeted immunological approaches are being studied, including agonists of toll-like 
receptors, modulators of apoptotic signaling, and checkpoint inhibition. 

Also, while past attempts at developing successful therapeutic vaccines have been unsuccessful, efforts continue to 
develop an effective HBV vaccine, using new vaccine technologies. 

9

Our Approach to the Treatment of HBV 

We are initially focusing on new core inhibitors that we expect to have an impact on capsid assembly and possibly 
interfere with other viral processes. Core inhibitors, also known as capsid assembly modulators or core protein 
allosteric modulators, are a novel class of replication inhibitors that have been shown to act at multiple steps in the 
HBV lifecycle. These inhibitors would be expected to prevent proper uncoating, nuclear import, assembly, and 
recycling. This approach is supported by early clinical validation, with the core inhibitor NVR 3-778 from Novira, 
JNJ-56136379 from Janssen, and ABI-H0731 from Assembly, demonstrating clinical reduction of viral DNA in 
chronic HBV patients in short-term Phase 1b or Phase 2 clinical studies. 

We recently identified our first core inhibitor candidate, EDP-514, which we are planning to advance into a Phase 1 
a/b study in 2019. In addition, we are conducting preclinical experiments with other mechanisms that target HBV. 
Due to the complex nature of HBV infection, it is widely believed that combination therapy may be necessary to 
provide the optimal therapeutic approach for this disease.

Our Out-Licensed HCV Protease Inhibitor Products

Background and Overview of HCV Market 

HCV is a virus that is a common cause of viral hepatitis, an inflammation of the liver. HCV is typically contracted 
by contact with the blood or other body fluids of another individual infected with HCV. HCV is a leading cause of 
chronic liver disease, including cirrhosis, liver failure and cancer, and the leading cause of death from liver disease 
in the United States. HCV disease progression occurs over a period of 20 to 30 years, with the majority of HCV-
infected individuals generally exhibiting no major symptoms in the early stages of the disease. Therefore, until a 
major symptom is diagnosed, many individuals are unaware they are infected and live undiagnosed without seeking 
treatment. For that reason, combined with the new availability of effective treatments for HCV, the United States 
Centers for Disease Control and Prevention, or CDC, issued new guidelines in 2013 recommending screening for all 
Americans born between the years 1945 and 1965 so that HCV-infected individuals will be aware of their condition 
and can consider treatment options. 

An estimated 71 million people worldwide are chronically infected with HCV and have an increased risk of 
eventually developing liver cirrhosis or liver cancer. Approximately 399,000 people die every year from HCV-
related liver diseases. The CDC estimated in 2016 that approximately 3.5 million people in the United States are 
chronically infected with HCV, with an estimated 41,200 new infections in 2016, the most recent year for which the 
CDC has published data. We believe that the chronically infected population remains significantly untreated, even 
with the introduction of several new regimens beginning in 2013.  

The approved treatments for HCV have provided significant benefit to HCV patients. To date, these treatments have 
cure rates approaching 100% in several subpopulations. Medical practice defines a “cure” as the point at which there 
is no quantifiable virus in a patient’s blood for a sustained period of time after cessation of therapy, which is often 
referred to as a sustained virologic response, or SVR. For AbbVie’s MAVYRET/MAVIRET regimen, the majority 
of chronic HCV patients only require 8 weeks of treatment compared to 12 weeks with VIEKIRA PAK® and other 
HCV regimens, including Gilead’s EPCLUSA® and HARVONI® in almost all HCV genotypes.

10

Since the introduction of Gilead’s Harvoni® and AbbVie’s VIEKIRA PAK® in late 2014, the reported worldwide 
sales of the leading HCV therapies have declined from $23 billion in 2015 to $12 billion in 2017. Through the first 
nine months of calendar 2018, reported worldwide net sales were $2.1 billion in the first calendar quarter, $2.1 
billion for the second calendar quarter and $1.9 billion for the third calendar quarter. HCV sales have declined since 
their peak in 2015 due to payers obtaining additional discounts, competitive market dynamics and a decline in the 
number of patients treated annually after the initial wave of diagnosed chronic HCV patients who had urgency for 
treatment. After the regulatory approvals of MAVYRET and Gilead’s VOSEVI in 2017, Johnson & Johnson and 
Merck announced they had terminated their development of additional HCV treatments. Despite the high numbers 
of HCV patients that have been successfully treated, there remains a large population of chronic HCV-infected 
patients who have yet to be treated with one of the newer “high cure” regimens. In addition, and as noted above, 
new HCV infections (principally in association with IV drug use) also represent an ongoing target population for 
treatment.

Scientific Background

Most of the currently approved HCV therapies targeting HCV focus directly on the viral life cycle and proteins that 
are critical to HCV replication. Replication of the HCV genome occurs on intracellular membranes and requires the 
participation of multiple viral proteins, some of which have enzymatic activities. Agents, often referred to as 
inhibitors, that target viral proteins directly are generally referred to as direct acting antivirals, or DAAs. All 
currently approved DAA therapies include one or a combination of two or more inhibitors of the NS3 protease, the 
NS5A protein, and the NS5B polymerase. 

NS3 Protease. As HCV replicates, it generates long strands of protein that must be processed into many individual 
active functional proteins that are referred to as non-structural proteins with the designated abbreviation NS, 
including NS3 and NS5A. The NS3 protease is responsible for most of this protein processing of the newly 
translated HCV protein, and plays an essential role in the viral life cycle. Inhibition of the protease prevents these 
new critical proteins from forming and therefore prevents replication and survival of the virus. 

NS5A. The NS5A protein has key roles in both the RNA replication of HCV and modulation of the physiology of its 
host cell in the body. Research has shown that targeting NS5A gives rise to profound antiviral activity, and as a 
result, this protein has emerged as an additional important DAA target for anti-HCV drugs. 

NS5B Polymerase. HCV is a single-stranded RNA virus, and NS5B is an HCV RNA polymerase responsible for 
synthesis of new HCV RNA, allowing the HCV genome to be copied and the virus to survive and replicate. Two 
separate classes of DAA inhibitors of NS5B polymerase are used as treatments for HCV. Nucleoside/nucleotide 
inhibitors of NS5B directly inhibit the active site of that enzyme and prevent further elongation of the RNA, and 
thus are equally active against all HCV genotypes. A second class, known as non-nucleoside inhibitors, affects 
replication of the RNA by altering the shape of the enzyme at remote sites on the enzyme surface, with the result 
being that any given non-nucleoside inhibitor is usually only active against certain HCV genotypes. 

Our Out-Licensed Products in AbbVie’s Marketed Therapies 

Glecaprevir - Our protease inhibitor, glecaprevir, which is part of the latest HCV regimen from AbbVie, was 
developed by AbbVie in combination with pibrentasvir, AbbVie’s second NS5A inhibitor.  This co-formulated 
combination, marketed as MAVYRET™ (U.S.) and MAVIRET™ (ex-U.S.), contains two novel DAAs that target 
and inhibit proteins essential for the replication of the hepatitis C virus. MAVYRET/MAVIRET is approved in the 
U.S., EU and Japan as an 8-week, pan-genotypic, fixed-dose combination treatment, dosed once-daily as three oral 
tablets, taken with food, for chronic HCV patients without cirrhosis and new to treatment. MAVYRET/MAVIRET 
is also approved as a treatment for patients with specific treatment challenges, including those GT-1 patients not 
cured by prior treatment experience with either a protease inhibitor or an NS5A inhibitor (but not both), and in 
patients with limited treatment options, such as those with severe chronic kidney disease (CKD) or those with 
genotype 3 chronic HCV. MAVYRET/MAVIRET is approved for use in patients across all stages of CKD with any 
of the major HCV genotypes (GT1-6). The approvals of MAVYRET/MAVIRET are supported by data from nine 
registrational studies in AbbVie’s clinical development program, which evaluated more than 2,300 patients in 27 
countries across all major HCV genotypes (GT1-6) and special populations:

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8 weeks for treatment-naïve, non-cirrhotics: In November 2016, results from several Phase 3 studies of 
this combination demonstrated 97.5% of chronic HCV infected patients without cirrhosis and new to 
treatment across all major genotypes (GT1-6) achieved sustained virologic response at 12 weeks post-
treatment, referred to as SVR12, with just 8 weeks of MAVYRET/MAVIRET treatment.

11

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8 weeks with chronic kidney disease: Results were also presented from AbbVie’s EXPEDITION-4 
study in chronic HCV patients with chronic kidney disease (CKD), in which 98% of patients 
(n=102/104) across all major genotypes (GT1-6) achieved SVR12 with 12 weeks of treatment with 
MAVYRET/MAVIRET.

8 weeks for GT-3: Data from AbbVie’s ENDURANCE-3 study were presented at the 2017 ILC, 
demonstrating that 95% of patients with challenging-to-treat, genotype 3 (GT3) chronic HCV infection, 
without cirrhosis and new to treatment, achieved SVR12 after 8 weeks of treatment with 
MAVYRET/MAVIRET.

Compensated cirrhosis: Based on data from AbbVie’s EXPEDITION-1 study, which demonstrated that 
99% of HCV-infected patients with genotype 1, 2, 4, 5 or 6 and compensated cirrhosis (Child-Pugh A) 
achieved SVR12 following 12 weeks of MAVYRET/MAVIRET treatment without ribavirin, 12 weeks 
of treatment with MAVYRET/MAVIRET is the approved duration for this regimen. Note: Results from 
one recently announced cohort of AbbVie’s Phase 3b EXPEDITION-8 study showed that with 8 weeks 
of MAVYRET treatment, 100 percent (n=273/273) of genotype 1, 2, 4, 5 and 6 patients achieved a 
sustained virologic response 12 weeks after treatment (SVR12) per protocol analysis.  A second cohort 
of the study is ongoing in genotype 3 (GT3) chronic HCV-infected patients.

Paritaprevir - The first protease inhibitor developed through our collaboration with AbbVie, paritaprevir, is part of 
AbbVie’s 3-DAA regimen approved for the treatment of genotype 1 and 4 HCV patients. This 3-DAA combination 
was sold as VIEKIRA PAK® (paritaprevir/ritonavir/ombitasvir/dasabuvir) in the U.S. from December 2014 to 
December 2018, and as VIEKIRAX®+EXVIERA® in most other jurisdictions, for non-cirrhotic patients and those 
with early stage, or compensated, cirrhosis. These regimens are in the process of being replaced by 
MAVYRET/MAVIRET in jurisdictions around the world since the latter was introduced in the U.S. in August 2017. 

Collaboration and License Agreement with AbbVie

We entered into a Collaborative Development and License Agreement with Abbott Laboratories in November 2006 to 
develop and commercialize HCV NS3 and NS3/4A protease inhibitors. The agreement, which was amended in January 
and December 2009, was then assigned to AbbVie Inc. on January 1, 2013 in connection with Abbott’s transfer of its 
research-based pharmaceuticals business to AbbVie. Under the agreement, we have granted AbbVie an exclusive, 
worldwide, royalty-bearing license, including a right to grant sublicenses, to specified intellectual property, including 
several issued U.S. patents, relating to protease inhibitors. We also granted AbbVie access to our drug discovery 
capabilities in the HCV NS3 and NS3/4A protease inhibitor field. AbbVie granted us a co-exclusive (together with 
AbbVie), royalty-free, fully paid license, without the right to grant sublicenses, to certain of AbbVie’s intellectual 
property, AbbVie’s interest in joint intellectual property and improvements discovered by AbbVie, for the purpose of 
allowing us to conduct certain development and commercialization activities in the United States relating to protease 
inhibitors. AbbVie is responsible for and has funded all costs associated with the development, manufacturing and 
commercialization of paritaprevir, glecaprevir and any other compounds under this agreement. Under the agreement, 
we are eligible to receive milestone payments and royalties with respect to these compounds. So long as a product 
candidate is being developed or commercialized under the agreement, we undertake not to conduct any activity, or 
grant licenses to a third party, relating to protease inhibitors. 

A joint steering committee was established under the agreement with review and oversight responsibilities for all 
research, development and commercialization activities. The joint steering committee is comprised of three of our 
senior personnel and three senior personnel from AbbVie; however, AbbVie has final authority to make all decisions 
regarding development and commercialization activities. 

The research program and the evaluation period, which was performed by both parties, ended in June 2011. The first 
commercialized compound was paritaprevir with the second commercialized compound, glecaprevir, approved in 
2017 and marketed under the tradenames MAVYRET™ (U.S.) or MAVIRET™ (ex-U.S.). Under this collaboration, 
we have received payments from AbbVie for license fees, proceeds from a sale of preferred stock, research funding 
payments and milestone payments totaling $396.0 million through September 30, 2018. 

12

We also receive annually tiered, double-digit royalties per protease inhibitor product developed under the 
agreement, which range from ten percent up to twenty percent, or on a blended basis from the low double digits up 
to the high teens. However, if a product is determined to be a combination product, as is the case for both 
glecaprevir and paritaprevir, the net sales of the combination product are adjusted on a country-by-country and 
product-by-product basis to reflect a good faith determination of the relative value of each pharmaceutically active 
ingredient, based on the estimated fair market value. This means that a portion of AbbVie’s worldwide annual net 
sales of a combination product or regimen is first allocated to one of our protease inhibitors and then that royalty-
bearing portion is multiplied by the annually tiered royalty rates to determine our actual royalty for the protease 
product in that regimen in a given period. Under the terms of our agreement, as amended in October 2014, 50% of 
AbbVie’s net sales of MAVYRET/MAVIRET are allocated to glecaprevir. In the case of regimens containing 
paritaprevir, 30% of net sales of 3-DAA regimens containing paritaprevir and 45% of net sales of 2-DAA regimens 
containing paritaprevir are allocated to paritaprevir for purposes of calculating our annually tiered royalties. 
Beginning with each January 1, the cumulative net sales of a given royalty-bearing protease inhibitor product start at 
zero for purposes of calculating the tiered royalties on a product-by-product basis. Under this collaboration, we have 
received royalty payments from AbbVie totaling $254.0 million through September 30, 2018. Further details of 
these tiered royalties are set forth in Note 7 in Notes to Consolidated Financial Statements included in this report, 
which are incorporated herein by this reference.  

Royalties owed to us under the agreement can be reduced by AbbVie in certain circumstances, including (i) if 
AbbVie exercises its right to license or otherwise acquire rights to intellectual property controlled by a third party 
where a product could not be legally developed or commercialized in a country without the third-party intellectual 
property right, (ii) where a product developed under the collaboration agreement is sold in a country and not covered 
by a valid patent claim in such country, or (iii) where sales of a generic product are equal to at least a specified 
percentage of AbbVie’s market share of a product in a country. 

AbbVie’s obligation to pay royalties on products developed under the agreement expires on a country-by-country 
and product-by-product basis upon the later of (i) the date of expiration of the last of the licensed patents with a 
valid claim covering the product in the applicable country, and (ii) ten years after the first commercial sale of the 
product in the applicable country. 

Our intellectual property existing as of the effective date of the agreement remains our property. Any intellectual 
property jointly developed is jointly owned. We will have the unilateral right to enforce our patent rights on any 
covered product following the first commercial sale of such product, as will AbbVie. In the event of infringement 
related to any of our patents, we will have the first right and option to initiate legal proceedings or take other actions. 
In the event of infringement related to any AbbVie patents, AbbVie will have the first right and option to initiate 
legal proceedings or take other actions. In the event of infringement of a joint patent right, we will discuss with 
AbbVie whether to initiate legal proceedings or take other actions. AbbVie will have the obligation to defend at its 
sole expense any actions brought against either party alleging infringement of third-party rights by reason of the 
activities conducted under the agreement and we will have the right to obtain separate counsel at our own expense. 
Additionally, AbbVie, at its sole expense, will be responsible for all trademark prosecution. 

Subject to the exceptions described above, a party’s rights and obligations under the agreement continue until: 
(i) such time as AbbVie is no longer developing a product candidate or (ii) if, as of the time AbbVie is no longer 
developing any product candidates, AbbVie is commercializing any other protease inhibitor product, such time as all 
royalty terms for all covered products and all co-development terms for all co-developed products have ended. 
Accordingly, the final expiration date of the agreement is currently indeterminable. 

Either party may terminate the agreement for cause in the event of a material breach, subject to prior notice and the 
opportunity to cure, or in the event of the other party’s bankruptcy. Additionally, AbbVie may terminate the 
agreement for any reason upon specified prior notice. 

If we terminate the agreement for cause or AbbVie terminates without cause, any licenses and other rights granted to 
AbbVie will terminate and AbbVie will be deemed to have granted us (i) a non-exclusive, perpetual, fully paid, 
worldwide, royalty-free license, with the right to sublicense, under AbbVie’s intellectual property used in any 
product candidate and (ii) an exclusive (even as to AbbVie), perpetual, fully paid, worldwide, royalty-free license, 
with the right to sublicense, under AbbVie’s interest in joint intellectual property rights to develop product 
candidates resulting from covered compounds and to commercialize any products derived from such compounds. 
Upon our request, AbbVie will also transfer to us all right, title and interest in any related product trademarks, 
regulatory filings and clinical trials. 

13

If AbbVie terminates the agreement for our uncured breach, the milestone and royalty payments payable by AbbVie 
may be reduced, the licenses granted to AbbVie will remain in place, we will be deemed to have granted AbbVie an 
exclusive license under our interest in joint intellectual property, AbbVie will continue to have the right to 
commercialize any covered products, and all rights and licenses granted to us by AbbVie will terminate. 

Drug Discovery 

We have internally discovered all of the compounds in our research and development programs. Our scientists have 
expertise in the areas of medicinal chemistry, molecular virology, pharmacology, and toxicology, with highly 
developed sets of skills in compound generation, target selection, screening and pharmacology, preclinical 
development and lead optimization. We are utilizing these skills and capabilities in our discovery and development 
of virology and liver disease product candidates. 

We focus on virology and liver disease indications representing large and growing market opportunities with 
significant unmet medical needs. Our selection of a particular therapeutic target within those disease indications 
takes into consideration the experience and expertise of our scientific team and includes our ability to generate 
robust medicinal chemistry structure-activity relationships to assist lead optimization and secure relevant intellectual 
property rights. Once we have identified lead compounds, they are tested using in vitro and in vivo pharmacology 
studies and in vivo research models of antiviral or antibacterial efficacy. 

Competition

We are engaged in segments of the pharmaceutical industry that are highly competitive and rapidly changing. Many 
large pharmaceutical and biotechnology companies, academic institutions, governmental agencies and other public 
and private research organizations are commercializing or pursuing the development of products that target HCV, 
NASH, PBC, RSV and HBV and other viral infections or liver diseases that we may target in the future.

Many of our competitors have substantially greater commercial infrastructures and financial, technical and 
personnel resources than we have, as well as drug candidates in late-stage clinical development. We will not be able 
to compete successfully unless we are able to: 

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design and develop products that are superior to other products in the market; 

attract qualified scientific, medical, regulatory, sales and marketing and commercial personnel; 

obtain patent and/or other proprietary protection for our processes and product candidates; 

obtain required regulatory approvals; and 

collaborate with others in the development and commercialization of new products. 

Established competitors may invest heavily to quickly discover and develop novel compounds that could make our 
product candidates obsolete. In addition, any new product that competes with an approved product must demonstrate 
compelling advantages in efficacy, convenience, tolerability and safety, or some combination of these factors, to 
overcome competition and to be commercially successful. 

We expect AbbVie’s MAVYRET/MAVIRET to continue to face price competition from existing approved products 
in the HCV market. This regimen currently faces competition in various world markets and subpopulations of HCV 
from Gilead’s Epclusa® (a fixed dose combination of sofosbuvir and velpatasvir), Vosevi™ (a triple combination 
therapy of sofosbuvir, velpatasvir and voxilaprevir approved by the FDA in July 2017 for specified sofosbuvir -
treatment failures and NS5A-inhibitor treatment failures) and Harvoni® (a fixed-dose combination of sofosbuvir and 
ledipasvir); and to a lesser extent - Merck’s Zepatier® (a fixed-dose combination of grazoprevir and elbasvir). 
Lastly, Gilead has announced plans to launch its own authorized generic versions of Epclusa and Harvoni in January 
2019 to be more competitive with MAVYRET/MAVIRET in managed Medicaid and Medicare Part D accounts. 
Gilead has announced that it will price these authorized generics to reflect more closely the discounts that health 
insurers and government payers receive for the branded versions of Epclusa and Harvoni. There are no other generic 
versions of Epclusa or Harvoni on the market and none are anticipated given the patents covering these drugs.

14

Competitive products in the form of other treatment methods or a vaccine for HCV may render AbbVie’s 
MAVYRET/MAVIRET obsolete or noncompetitive. This regimen will face competition based on its price, 
reimbursement coverage, AbbVie’s marketing and sales capabilities, patent position, safety and effectiveness, and 
other factors. If any of AbbVie’s HCV regimens face competition from generic versions of these products, the 
collaboration agreement provides that the royalty rate applicable to our protease product contained in the regimen is 
reduced significantly by a specified percentage on a product-by-product, country-by-country basis. If AbbVie is not 
able to compete effectively against its competitors in HCV, our business will not grow and our financial condition, 
operations and stock price will suffer.

We also expect our other product candidates will face intense and increasing competition in the antiviral and NASH 
markets as advanced technologies and products become available. For RSV, there are currently no safe and effective 
therapies for already established RSV infection. Several companies are seeking new antiviral treatments for RSV 
infection in adult and pediatric settings. Ark Bioscienes, Johnson & Johnson, Gilead, Pulmocide and ReViral each 
have compounds in clinical development, as does Ablynx with a potential therapeutic antibody. A prophylactic, 
monoclonal-antibody-based treatment from MedImmune, which is commercialized by AbbVie outside of the U.S., 
is approved for infants considered at high risk for RSV infection; however studies have found that most young 
children with RSV infection were previously healthy, and thus would not normally be prescribed prophylactic 
treatment. In addition, a number of companies have RSV vaccines in development, primarily directed at prevention 
of RSV infection, and some companies are also evaluating vaccines in a therapeutic mode for treatment of 
established RSV infection.

Though there is currently no approved treatment for NASH, we expect significant competition from other 
companies in the development of new treatments for NASH and related conditions. We are aware of several 
companies with NASH programs that are significantly more advanced than ours, including companies with 
compounds in Phase 3 clinical trials in NASH, namely Intercept, Genfit, Gilead, and Tobira (Allergan). In May 
2016, the FDA granted conditional approval for Intercept’s FXR agonist (brand name Ocaliva®) for the treatment of 
primary biliary cholangitis (PBC) in combination with first line therapy ursodeoxycholic acid (UDCA) in adults 
with an inadequate response to UDCA, or as monotherapy in adults unable to tolerate UDCA. In addition, a number 
of companies have NASH or related programs with compounds in Phase 2 clinical trials. These companies include 
Astra-Zeneca, BMS, Boehringer Ingelheim, Can-Fite BioPharma, Conatus, Cirius, Cymabay, Galectin, Galmed, 
Gilead, GlaxoSmithKline, Immuron, Inventiva, Madrigal, Medicinova, Novartis, NGM, Novo Nordisk, Pfizer, 
Viking, and Zydus. A significant number of other companies are conducting earlier stage clinical trials that may be 
applicable in NASH and other cholestatic diseases. There are also additional companies conducting preclinical 
studies in these disease areas.

Similarly, HBV represents a competitive therapeutic area. While there are antiviral medications prescribed for 
treatment for HBV, they generally have low true cure rates. Many companies are seeking to develop new HBV 
drugs that alone or in combination with other mechanisms could lead to a functional cure of HBV. Arbutus, 
Assembly, Gilead, HEC, Ionis/GSK, Johnson & Johnson, Maxwell, Replicor, and Spring Bank have Phase 2 
programs in progress, with many of these companies conducting earlier stage programs as well. In addition, a 
number of companies have Phase 1 or earlier stage HBV programs, including Aicuris, Alnylam, Altimmune, 
Arrowhead, Contravir, Dicerna, Enyo, Roche and Transgene. 

If we are not able to develop new products that can compete effectively against our current and future competitors, 
our business will not grow and our financial condition, operations and stock price will suffer.

Intellectual Property 

As part of our business strategy, we actively seek patent protection for our product candidates in the United States 
and certain major foreign jurisdictions and file additional patent applications, when appropriate, to cover 
improvements to our compounds. We also rely on trade secrets, internal know-how, technological innovations and 
agreements with third parties to develop, maintain and protect our competitive position. Our ability to be 
competitive will depend on the success of this strategy. 

15

Each of our major programs, including RSV, NASH, PBC, HBV and HCV, typically has several issued patents and 
pending patent claims in the program area containing claims to compounds, methods of use and processes for 
synthesis. However, only a few of the issued patents and/or pending patent applications cover the lead product 
candidate in a given program. 

RSV, NASH, PBC and HBV Programs. Our patent portfolio directed to N-protein inhibitors for RSV, FXR agonists 
for NASH, PBC and fibrosis, and core inhibitors for HBV includes pending U.S. patent applications as well as 
numerous foreign patent applications. 

HCV NS3 Protease Inhibitor Program. The patent portfolio directed to the HCV protease inhibitor program with 
AbbVie includes U.S. patents and foreign patents, as well as non-provisional applications. The issued U.S. 
composition-of-matter patent covering paritaprevir is expected to expire in 2031. The issued U.S. composition-of-
matter patent covering glecaprevir is expected to expire in 2032. AbbVie is a joint owner of a number of the non-
provisional patent applications. AbbVie also has rights to some or all of these patents and patent applications 
pursuant to its collaboration agreement with us.

We may obtain patents for certain compounds many years before we obtain marketing approval for products 
containing such compounds. Because patents have a limited life, which usually begins to run well before the first 
commercial sale of the related product, the commercial value of the patent may be limited. However, we may be 
able to apply for patent term extensions in the United States and in a number of European countries, compensating 
in part for delays in obtaining marketing approval, but we cannot be certain we will obtain such extensions. 

It is also very important that we do not infringe patents or other proprietary rights of others. If we do infringe such 
patents or other proprietary rights, we could be prevented from developing or selling products or from using the 
processes covered by those patents, could be required to pay substantial damages, or could be required to obtain a 
license from the third party to allow us to use their technology, which may not be available on commercially 
reasonable terms or at all. If we were not able to obtain a required license or develop alternative technologies, we 
may be unable to develop or commercialize some or all of our products, and our business could be adversely 
affected. 

In addition, we jointly own patent applications, together with AbbVie, that claim paritaprevir and glecaprevir as a 
chemical entity. However, there is no guarantee that such applications will issue. Further, the existence of issued 
patents does not guarantee our right to practice the patented technology or commercialize the patented product. 
Third parties may have already or could obtain rights to patents that could be used to prevent or attempt to prevent 
us from commercializing our product candidates. If these other parties are successful in obtaining valid and 
enforceable patents, and establishing our infringement of those patents, we could be prevented from 
commercializing our product candidates unless we were able to obtain a license under such patents, which may not 
be available on commercially reasonable terms or at all. 

Much of our scientific capabilities depend upon the knowledge, experience and skills of key scientific and technical 
personnel. To protect our rights to our proprietary know-how and technology, we endeavor to require all employees, 
as well as our consultants and advisors, when feasible, to enter into confidentiality agreements that require 
disclosure and assignment to us of ideas, developments, discoveries and inventions made by these employees, 
consultants and advisors in the course of their service to us. 

We may be unable to obtain, maintain and protect the intellectual property rights necessary to conduct our business, 
and we may be subject to claims that we infringe or otherwise violate the intellectual property rights of others, 
which could materially harm our business. For more information, see “Risk Factors—Risks Related to Our 
Intellectual Property Rights.” 

Government Regulation 

Government authorities in the United States, at the federal, state and local level, and in other countries extensively 
regulate, among other things, the research, development, testing, manufacture, quality control, approval, labeling, 
packaging, storage, record-keeping, promotion, advertising, distribution, post-approval monitoring and reporting, 

16

marketing and export and import of products such as those we develop. Any pharmaceutical candidate that we 
develop must be approved by the FDA before it may be legally marketed in the United States and by the appropriate 
foreign regulatory agency before it may be legally marketed in foreign countries. 

United States Drug Development Process 

In the United States, the FDA regulates drugs under the Federal Food, Drug and Cosmetic Act, or FDCA, and 
implementing regulations. Drugs are also subject to other federal, state and local statutes and regulations. The 
process of obtaining regulatory approvals and the subsequent compliance with appropriate federal, state, local and 
foreign statutes and regulations require the expenditure of substantial time and financial resources. Failure to comply 
with the applicable United States requirements at any time during the product development process, approval 
process or after approval, may subject an applicant to administrative or judicial sanctions. FDA sanctions could 
include refusal to approve pending applications, withdrawal of an approval, a clinical hold, warning letters, product 
recalls, product seizures, total or partial suspension of production or distribution, injunctions, fines, refusals of 
government contracts, restitution, disgorgement or civil or criminal penalties. Any agency or judicial enforcement 
action could have a material adverse effect on us. 

The process required by the FDA before a drug may be marketed in the United States generally involves the 
following: 

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

Completion of preclinical laboratory tests, animal studies and formulation studies according to Good 
Laboratory Practice, or GLPs, or other applicable regulations; 

Submission to the FDA of an Investigational New Drug Application, or an IND, which must become 
effective before human clinical trials may begin; 

Performance of adequate and well-controlled human clinical trials according to the FDA’s current Good 
Clinical Practice, or GCPs, to establish the safety and efficacy of the proposed drug for its intended use; 

Submission to the FDA of a New Drug Application, or an NDA, for a new drug product; 

Satisfactory completion of an FDA inspection of the manufacturing facility or facilities where the drug 
is to be produced to assess compliance with the FDA’s current Good Manufacturing Practice standards, 
or cGMP, to assure that the facilities, methods and controls are adequate to preserve the drug’s identity, 
strength, quality and purity; 

Potential FDA audit of the nonclinical and clinical trial sites that generated the data in support of the 
NDA; and 

FDA review and approval of the NDA. 

The lengthy process of seeking required approvals, which can often take anywhere from six months from the time 
the NDA is filed if there is a priority review for a breakthrough therapy to twelve months for a standard review, and 
the continuing need for compliance with applicable statutes and regulations require the expenditure of substantial 
resources. There can be no certainty that approvals will be granted. 

Before testing any compounds with potential therapeutic value in humans, the product candidate enters the 
preclinical testing stage. Preclinical tests include laboratory evaluations of product chemistry, toxicity and 
formulation, as well as animal studies to assess the potential safety and activity of the product candidate. The 
conduct of the preclinical tests must comply with GLP and other federal regulations and requirements. The sponsor 
must submit the results of the preclinical tests, together with manufacturing information, analytical data, any 
available clinical data or literature and a proposed clinical protocol, to the FDA as part of the IND. The IND 
automatically becomes effective 30 days after receipt by the FDA, unless the FDA places the clinical trial on a 
clinical hold within that 30-day time period. In such a case, the IND sponsor and the FDA must resolve any 
outstanding concerns before the clinical trial can begin. The FDA may also impose clinical holds on a drug at any 
time before or during clinical trials due to safety concerns or non-compliance. Accordingly, we cannot assure that 
submission of an IND will result in the FDA allowing clinical trials to begin, or that, once begun, issues will not 
arise that result in suspension or termination of such trial. 

17

Clinical trials involve the administration of the product candidate to healthy volunteers or patients having the disease 
being studied under the supervision of qualified investigators, generally physicians not employed by or under the 
trial sponsor’s control. Clinical trials are conducted under protocols detailing, among other things, the objectives of 
the clinical trial, dosing procedures, subject selection and exclusion criteria, and the parameters to be used to 
monitor subject safety. Each protocol must be submitted to the FDA as part of the IND. Clinical trials must be 
conducted in accordance with the FDA’s GCP requirements. Further, each clinical trial must be reviewed and 
approved by an independent institutional review board, or IRB, at or servicing each institution at which the clinical 
trial will be conducted. An IRB is charged with protecting the welfare and rights of trial participants and considers 
such items as whether the risks to individuals participating in the clinical trials are minimized and are reasonable in 
relation to anticipated benefits. The IRB also approves the informed consent form that must be provided to each 
clinical trial subject or his or her legal representative and must monitor the clinical trial until it is completed. 

Human clinical trials prior to approval are typically conducted in three sequential phases that may overlap or be 
combined: 

(cid:129)

(cid:129)

(cid:129)

Phase 1. The drug is initially introduced into healthy humans and tested for safety, dosage tolerance, 
absorption, metabolism, distribution and excretion. In the case of some products for severe or life-
threatening diseases, especially when the product may be too inherently toxic to ethically administer to 
healthy volunteers, the initial human testing is often conducted only in patients having the specific 
disease. 

Phase 2. The drug is evaluated in a limited patient population to identify possible adverse effects and 
safety risks, to preliminarily evaluate the efficacy of the product for specific targeted diseases and to 
determine dosage tolerance, optimal dosage and dosing schedule for patients having the specific disease. 

Phase 3. Clinical trials are undertaken to further evaluate dosage, clinical efficacy and safety in an 
expanded patient population at geographically dispersed clinical trial sites. These clinical trials, which 
usually involve more patients than earlier trials, are intended to establish the overall risk/benefit ratio of 
the product and provide an adequate basis for product labeling. Generally, at least two adequate and 
well-controlled Phase 3 clinical trials are required by the FDA for approval of an NDA. 

Post-approval studies, or Phase 4 clinical trials, may be conducted after initial marketing approval. These studies are 
used to gain additional experience from the treatment of patients in the intended therapeutic indication and may be 
required by the FDA as part of the approval process. 

Progress reports detailing the results of the clinical trials must be submitted at least annually to the FDA and written 
IND safety reports must be submitted to the FDA by the investigators for serious and unexpected adverse events or 
any finding from tests in laboratory animals that suggests a significant risk for human patients. Phase 1, Phase 2 and 
Phase 3 clinical trials may not be completed successfully within any specified period, if at all. The FDA, or the 
sponsor or its data safety monitoring board, may suspend a clinical trial at any time on various grounds, including a 
finding that the research patients are being exposed to an unacceptable health risk. Similarly, an IRB can suspend or 
terminate approval of a clinical trial at its institution if the clinical trial is not being conducted in accordance with the 
IRB’s requirements or if the drug has been associated with unexpected serious harm to patients. 

Concurrent with clinical trials, companies usually complete additional animal studies and develop additional 
information about the chemistry and physical characteristics of the drug as well as finalize a process for 
manufacturing the product in commercial quantities in accordance with cGMP requirements. The manufacturing 
process must be capable of consistently producing quality batches of the product candidate and, among other things, 
must include methods for testing the identity, strength, quality and purity of the final drug. Additionally, appropriate 
packaging must be selected and tested and stability studies must be conducted to demonstrate that the product 
candidate does not undergo unacceptable deterioration over its shelf life. 

U.S. Review and Approval Processes 

The results of product development, preclinical studies and clinical trials, along with descriptions of the 
manufacturing process, analytical tests conducted on the chemistry of the drug, proposed labeling and other relevant 
information are submitted to the FDA as part of an NDA requesting approval to market the product. The submission 
of an NDA is subject to the payment of substantial user fees by the applicant; a waiver of such fees may be obtained 
under certain limited circumstances. 

18

In addition, under the Pediatric Research Equity Act, or PREA, an NDA or supplement to an NDA must contain 
data to assess the safety and effectiveness of the drug for the claimed indications in all relevant pediatric 
subpopulations and to support dosing and administration for each pediatric subpopulation for which the product is 
safe and effective. The FDA may grant deferrals for submission of pediatric data or full or partial waivers. 

The FDA reviews all NDAs submitted before it accepts them for filing and may request additional information 
rather than accepting an NDA for filing. Once the submission is accepted for filing, the FDA begins an in-depth 
review of the NDA. Under the goals and policies agreed to by the FDA under the Prescription Drug User Fee Act, or 
PDUFA, the FDA has twelve months in which to complete its initial review of a standard NDA and respond to the 
applicant, and six months for a priority NDA. The FDA does not always meet its PDUFA goal dates for standard 
and priority NDAs. 

After the NDA submission is accepted for filing, the FDA reviews the NDA to determine, among other things, 
whether the proposed product is safe and effective for its intended use and whether the product is being 
manufactured in accordance with cGMP to assure and preserve the product’s identity, strength, quality and purity. In 
addition to its own review, the FDA may refer applications for novel drug products or drug products that present 
difficult questions of safety or efficacy to an advisory committee, typically a panel that includes clinicians and other 
experts, for review, evaluation and a recommendation as to whether the application should be approved and under 
what conditions. The FDA is not bound by the recommendations of an advisory committee, but it considers such 
recommendations carefully when making decisions. During the approval process, the FDA also will determine 
whether a Risk Evaluation and Mitigation Strategy, or REMS, is necessary to assure the safe use of the drug. If the 
FDA concludes that a REMS is needed, the sponsor of the NDA must submit a proposed REMS; the FDA will not 
approve the NDA without a REMS, if required. 

Before approving an NDA, the FDA will inspect the facilities at which the product is to be manufactured. The FDA 
will not approve the product unless it determines that the manufacturing processes and facilities are in compliance 
with cGMP requirements and are adequate to assure consistent production of the product within required 
specifications. Additionally, before approving an NDA, the FDA will typically inspect one or more clinical sites to 
assure compliance with GCP. If the FDA determines that the application, manufacturing process or manufacturing 
facilities are not acceptable it will outline the deficiencies in the submission and often will request additional testing 
or information. 

The NDA review and approval process is lengthy and difficult, and the FDA may refuse to approve an NDA if the 
applicable regulatory criteria are not satisfied or may require additional clinical data or other data and information. 
Even if such data and information is submitted, the FDA may ultimately decide that the NDA does not satisfy the 
criteria for approval. Data obtained from clinical trials are not always conclusive and may be susceptible to varying 
interpretations, which could delay, limit or prevent regulatory approval. The FDA will issue a “complete response” 
letter if the agency decides not to approve the NDA. The complete response letter usually describes all of the 
specific deficiencies in the NDA identified by the FDA. The deficiencies identified may be minor, for example, 
requiring labeling changes, or major, for example, requiring additional clinical trials. Additionally, the complete 
response letter may include recommended actions that the applicant might take to place the application in a 
condition for approval. If a complete response letter is issued, the applicant may either resubmit the NDA, 
addressing all of the deficiencies identified in the letter, or withdraw the application. 

If a product receives regulatory approval, the approval may be limited to specific diseases and dosages or the 
indications for use may otherwise be limited, which could restrict the commercial value of the product. Further, the 
FDA may require that certain contraindications, warnings or precautions be included in the product labeling. In 
addition, the FDA may require Phase 4 testing, which involves clinical trials designed to further assess a product’s 
safety and effectiveness and may require testing and surveillance programs to monitor the safety of approved 
products that have been commercialized. 

Expedited Development and Review Programs 

The FDA has four programs intended to expedite the development and review of new drugs addressing unmet 
medical needs or treating serious or life-threatening conditions: fast track, breakthrough therapy, priority review, and 
accelerated approval. 

19

The FDA “fast track” program is intended to expedite or facilitate the process for reviewing new products to treat 
serious or life-threatening conditions and address unmet medical needs. Fast track designation applies to the 
combination of the product and the specific indication for which it is being studied. Under the fast track program, 
the sponsor will have more frequent interactions with the FDA during drug development, and may also submit 
sections of the NDA on a rolling basis to the FDA for review before submitting the complete application. Fast track 
does not guarantee that a product will be reviewed more quickly or receive FDA approval. 

The FDA “breakthrough therapy” program is intended to expedite the development and review of drugs for serious 
or life-threatening conditions. Preliminary clinical evidence must show that the drug may have substantial 
improvement over existing therapies on one or more clinically significant endpoints. Although the drug does not 
have to address an unmet medical need, designation of breakthrough therapy status carries all the “fast track” 
program features. Additionally, the breakthrough therapy program entitles the sponsor to earlier and more frequent 
interaction with the FDA review team regarding development of nonclinical and clinical data, and allows the FDA 
to offer product development and regulatory advice necessary to shorten the time for product approval. The 
breakthrough therapy status does not guarantee a quicker development or review of the product, and does not ensure 
FDA approval. 

The FDA also has a “priority review” program for products offering significant improvement in the treatment, 
diagnosis or prevention of a disease. The goal of the priority review program is to shorten the review period to six 
months from the ten months required for standard review. Any drug with breakthrough therapy, accelerated approval 
designation, or fast track can be granted priority review if it meets the necessary criteria. 

The FDA “accelerated approval” program is intended to expedite the development and review of products with the 
potential to treat serious or life-threatening illnesses and provide meaningful therapeutic benefit over existing 
treatments. The program allows approval of a product on the basis of adequate and well-controlled clinical studies 
establishing that the product has an effect on a surrogate endpoint that is reasonably likely to predict a clinical 
benefit, or on the basis of an effect on a clinical endpoint that can be measured earlier than survival or irreversible 
morbidity. As a condition of approval, the FDA generally requires that a sponsor of the product perform adequate 
and well-controlled post-marketing clinical studies to establish safety and efficacy for the approved indication. 
Failure to conduct such studies or failure of the studies to establish required safety and efficacy may result in 
revocation of approval. The FDA also requires, as a condition for accelerated approval, pre-approval of promotional 
materials, which could adversely impact the timing of the commercial launch or subsequent marketing of the 
product. 

Post-Approval Requirements 

Any drug products for which we receive FDA approvals are subject to continuing regulation by the FDA. Certain 
requirements include, among other things, record-keeping requirements, reporting of adverse experiences with the 
product, providing the FDA with updated safety and efficacy information on an annual basis or more frequently for 
specific events, product sampling and distribution requirements, complying with certain electronic records and 
signature requirements and complying with FDA promotion and advertising requirements. These promotion and 
advertising requirements include, among others, standards for direct-to-consumer advertising, prohibitions against 
promoting drugs for uses or in patient populations that are not described in the drug’s approved labeling (known as 
“off-label use”), rules for conducting industry-sponsored scientific and educational activities and promotional 
activities involving the internet. Failure to comply with FDA requirements can have negative consequences, 
including the immediate discontinuation of noncomplying materials, adverse publicity, enforcement letters from the 
FDA, mandated corrective advertising or communications with doctors, and civil or criminal penalties. Although 
physicians may prescribe legally available drugs for off-label uses, manufacturers may not market or promote such 
off-label uses. 

20

We rely, and expect to continue to rely, on third parties for the production of clinical and commercial quantities of 
our product candidates. Manufacturers of our product candidates are required to comply with applicable FDA 
manufacturing requirements contained in the FDA’s cGMP regulations. These regulations require, among other 
things, quality control and quality assurance as well as the corresponding maintenance of comprehensive records 
and documentation. Drug manufacturers and other entities involved in the manufacture and distribution of approved 
drugs are also required to register their establishments and list any products they make with the FDA and to comply 
with related requirements in certain states. These entities are further subject to periodic unannounced inspections by 
the FDA and certain state agencies for compliance with cGMP and other laws. Accordingly, manufacturers must 
continue to expend time, money and effort in the area of production and quality control to maintain cGMP 
compliance. Discovery of problems with a product after approval may result in serious and extensive restrictions on 
a product, manufacturer or holder of an approved NDA. These restrictions may include suspension of a product until 
the FDA is assured that quality standards can be met, continuing oversight of manufacturing by the FDA under a 
“consent decree,” which frequently includes the imposition of costs and continuing inspections over a period of 
many years, as well as possible withdrawal of the product from the market. In addition, changes to the 
manufacturing process generally require prior FDA approval before being implemented. Other types of changes to 
the approved product, such as adding new indications and additional labeling claims, are also subject to further FDA 
review and approval. 

The FDA also may require post-marketing testing, known as Phase 4 testing, as well as risk minimization action 
plans and surveillance to monitor the effects of an approved product or place conditions on an approval that could 
otherwise restrict the distribution or use of the product. 

U.S. Patent Term Restoration and Marketing Exclusivity 

Drug Price Competition and Patent Term Restoration Act of 1984 

Depending upon the timing, duration and specifics of the FDA approval of the use of our product candidates, some 
of our United States patents may be eligible for limited patent term extension under the Drug Price Competition and 
Patent Term Restoration Act of 1984, commonly referred to as the Hatch-Waxman Amendments. The Hatch-
Waxman Amendments permit a patent restoration term of up to five years as compensation for patent term lost 
during federal regulatory review preceding the FDA regulatory review process. However, patent term restoration 
cannot extend the remaining term of a patent beyond a total of 14 years from the product’s approval date. The patent 
term restoration period is generally one-half the time between the effective date of an IND and the submission date 
of an NDA plus the time between the submission date of an NDA and the approval of that application. Only one 
patent applicable to an approved drug is eligible for the extension and the application for the extension must be 
submitted within 60 days of approval, prior to the expiration of the patent. The United States Patent and Trademark 
Office, in consultation with the FDA, reviews and approves the application for any patent term extension or 
restoration. In the future, we may apply for restoration of patent term for one of our currently owned or licensed 
patents to add patent life beyond its current expiration date, depending on the expected length of the clinical trials 
and other factors involved in the filing of the relevant NDA. However, there is no guarantee that any such 
application will be approved. 

Federal Food, Drug and Cosmetic Act (“FDCA”) 

Market exclusivity provisions under the FDCA, which are independent of patent status and any patent related 
extensions, can also delay the submission or the approval of certain applications of other companies seeking to 
reference another company’s NDA. If the new drug is a new chemical entity subject to an NDA, the FDCA provides 
a five-year period of non-patent marketing exclusivity within the United States to the first applicant to obtain 
approval of an NDA for a new chemical entity. A drug is a new chemical entity if the FDA has not previously 
approved any other new drug containing the same active moiety, which is the molecule or functional group of a 
molecule responsible for the action of the drug substance. During the exclusivity period, the FDA may not accept for 
review an abbreviated new drug application, or ANDA, or a so-called Section 505(b)(2) NDA, submitted by another 
company for another version of such drug where the applicant does not own or have a legal right of reference to all 
the data required for approval. However, such an application may be submitted after four years if it contains a 
certification of patent invalidity or non-infringement to one of the patents listed with the FDA by the innovator NDA 
holder. The FDCA also provides three years of marketing exclusivity for an NDA, or supplement to an existing 

21

NDA if new clinical investigations, other than bioavailability studies, that were conducted or sponsored by the 
applicant are deemed by the FDA to be essential to the approval of the application, for example new indications, 
dosages or strengths of an existing drug. This three-year exclusivity covers only the conditions associated with the 
new clinical investigations and does not prohibit the FDA from approving ANDAs for drugs containing the original 
active agent. Five-year and three-year exclusivity will not delay the submission or approval of a full NDA. 
However, an applicant submitting a full NDA would be required to conduct or obtain a right of reference to all of 
the preclinical studies and adequate and well-controlled clinical trials necessary to demonstrate safety and 
effectiveness. 

Other U.S. Healthcare Laws and Compliance Requirements 

In the United States, our activities are potentially subject to regulation by various federal, state and local authorities 
in addition to the FDA, including the Centers for Medicare and Medicaid Services (formerly the Health Care 
Financing Administration), other divisions of the United States Department of Health and Human Services (e.g., the 
Office of Inspector General), the United States Department of Justice and individual United States Attorney offices 
within the Department of Justice, state attorney generals and state and local governments. For example, sales, 
marketing and scientific/educational grant programs must comply with the anti-fraud and abuse provisions of the 
Social Security Act, the False Claims Act, the privacy and security provisions of the Health Insurance Portability 
and Accountability Act, or HIPAA, and similar state laws, each as amended. Pricing and rebate programs must 
comply with the Medicaid rebate requirements of the Omnibus Budget Reconciliation Act of 1990 and the Veterans 
Health Care Act of 1992, each as amended. If products are made available to authorized users of the Federal Supply 
Schedule of the General Services Administration, additional laws and requirements apply. Under the Veterans 
Health Care Act, or VHCA, drug companies are required to offer certain pharmaceutical products at a reduced price 
to a number of federal agencies including the United States Department of Veterans Affairs and United States 
Department of Defense, the Public Health Service and certain private Public Health Service—designated entities in 
order to participate in other federal funding programs including Medicare and Medicaid. Recent legislative changes 
purport to require that discounted prices be offered for certain United States Department of Defense purchases for its 
TRICARE program via a rebate system. Participation under the VHCA requires submission of pricing data and 
calculation of discounts and rebates pursuant to complex statutory formulas, as well as the entry into government 
procurement contracts governed by the Federal Acquisition Regulations. 

In order to distribute products commercially, we must comply with state laws that require the registration of 
manufacturers and wholesale distributors of pharmaceutical products in a state, including, in certain states, 
manufacturers and distributors who ship products into the state even if such manufacturers or distributors have no 
place of business within the state. Some states also impose requirements on manufacturers and distributors to 
establish the pedigree of product in the chain of distribution, including some states that require manufacturers and 
others to adopt new technology capable of tracking and tracing product as it moves through the distribution chain. 
Several states have enacted legislation requiring pharmaceutical companies to establish marketing compliance 
programs, file periodic reports with the state, make periodic public disclosures on sales, marketing, pricing, clinical 
trials and other activities, and/or register their sales representatives, as well as to prohibit pharmacies and other 
healthcare entities from providing certain physician prescribing data to pharmaceutical companies for use in sales 
and marketing, and to prohibit certain other sales and marketing practices. All of our activities are potentially subject 
to federal and state consumer protection and unfair competition laws. 

Europe / Rest of World Government Regulation 

In addition to regulations in the United States, we will be subject to a variety of regulations in other jurisdictions 
governing, among other things, clinical trials and any commercial sales and distribution of our products. 

Whether or not we obtain FDA approval for a product, we must obtain the requisite approvals from regulatory 
authorities in foreign countries prior to the commencement of clinical trials or marketing of the product in those 
countries. Certain countries outside of the United States have a similar process that requires the submission of a 
clinical trial application much like the IND prior to the commencement of human clinical trials. In the European 
Union, for example, a clinical trial application, or CTA, must be submitted to each country’s national health 
authority and an independent ethics committee, much like the FDA and IRB, respectively. Once the CTA is 
approved in accordance with a country’s requirements, clinical trials may proceed. 

22

The requirements and process governing the conduct of clinical trials, product licensing, pricing and reimbursement 
vary from country to country. In all cases, the clinical trials are conducted in accordance with International 
Conference on Harmonisation (ICH) / WHO Good Clinical Practice standards and the applicable regulatory 
requirements and the ethical principles that have their origin in the Declaration of Helsinki. 

To obtain regulatory approval of an investigational drug under European Union regulatory systems, we must submit 
a marketing authorization application to the European Medicines Agency, or the EMA. The application used to file 
an NDA in the United States is similar to that required in the European Union, with the exception of, among other 
things, country-specific document requirements. 

For other countries outside of the European Union, such as countries in Eastern Europe, Latin America or Asia, the 
requirements governing the conduct of clinical trials, product licensing, pricing and reimbursement vary from 
country to country. In all cases, again, the clinical trials are conducted in accordance with GCPs and the applicable 
regulatory requirements and the ethical principles that have their origin in the Declaration of Helsinki. 

If we fail to comply with applicable foreign regulatory requirements, we may be subject to, among other things, 
fines, suspension or withdrawal of regulatory approvals, product recalls, seizure of products, operating restrictions 
and criminal prosecution. 

Pharmaceutical Coverage, Pricing and Reimbursement 

Significant uncertainty exists as to the coverage and reimbursement status of any product candidates for which we 
obtain regulatory approval. In the United States and markets in other countries, sales of any products for which we 
receive regulatory approval for commercial sale will depend in part on the availability of reimbursement from third-
party payors. Third-party payors include government health administrative authorities, managed care providers, 
private health insurers and other organizations. The process for determining whether a payor will provide coverage 
for a drug product may be separate from the process for setting the price or reimbursement rate that the payor will 
pay for the drug product. Third-party payors may limit coverage to specific drug products on an approved list, or 
formulary, which might not include all of the FDA-approved drug products for a particular indication. Third-party 
payors are increasingly challenging the price and examining the medical necessity and cost-effectiveness of medical 
products and services, in addition to their safety and efficacy. We may need to conduct expensive pharmaco-
economic studies in order to demonstrate the medical necessity and cost-effectiveness of our products, in addition to 
the costs required to obtain the FDA approvals. Our product candidates may not be considered medically necessary 
or cost-effective. A payor’s decision to provide coverage for a drug product does not imply that an adequate 
reimbursement rate will be approved. Adequate third-party reimbursement may not be available to enable us to 
maintain price levels sufficient to realize an appropriate return on our investment in product development. 

In 2003, the United States government enacted legislation providing a partial prescription drug benefit for Medicare 
recipients, which became effective at the beginning of 2006. Government payment for some of the costs of 
prescription drugs may increase demand for any products for which we receive marketing approval. However, to 
obtain payments under this program, we would be required to sell products to Medicare recipients through 
prescription drug plans operating pursuant to this legislation. These plans will likely negotiate discounted prices for 
our products. Federal, state and local governments in the United States continue to consider legislation to limit the 
growth of healthcare costs, including the cost of prescription drugs. Future legislation could limit payments for 
pharmaceuticals such as the product candidates that we are developing. 

The Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act, 
collectively known as the Affordable Care Act, substantially changed the way healthcare is financed by both 
governmental and private insurers, and significantly impacted the pharmaceutical industry. 

23

The comprehensive overhaul has extended coverage to approximately 20 million previously uninsured Americans. 
Since its adoption, the Affordable Care Act contains a number of provisions, including those governing enrollment 
in federal healthcare programs, reimbursement changes and fraud and abuse, which have affected existing 
government healthcare programs and have resulted in the development of new programs, including Medicare 
payment for performance initiatives and improvements to the physician quality reporting system and feedback 
program. Additionally, the Affordable Care Act, as limited by the United States Supreme Court’s decision in June 
2012: 

(cid:129)

(cid:129)

(cid:129)

(cid:129)

increases the minimum level of Medicaid rebates payable by manufacturers of brand-name drugs from 
15.1% to 23.1%; 

requires collection of rebates for drugs paid by Medicaid managed care organizations; 

requires manufacturers to participate in a coverage gap discount program, under which they must agree 
to offer 50% point-of-sale discounts off negotiated prices of applicable brand drugs to eligible 
beneficiaries during their coverage gap period, as a condition for the manufacturer’s outpatient drugs to 
be covered under Medicare Part D, beginning January 2011; and 

imposes a non-deductible annual fee on pharmaceutical manufacturers or importers who sell “branded 
prescription drugs” to specified federal government programs. 

There have been proposals by President Trump and the Republican majorities in both houses of the U.S. Congress to 
repeal or replace all or portions of the Affordable Care Act but to date no such legislation has been agreed upon. At 
this time, it remains unclear what legislation, if any, to repeal or replace the Affordable Care Act will become law, 
or what impact any such legislation may have on our existing product candidates, any of our future product 
candidates or AbbVie’s commercialization of its HCV regimens. 

Different pricing and reimbursement schemes exist in other countries. In the European Union, governments 
influence the price of pharmaceutical products through their pricing and reimbursement rules and control of national 
healthcare systems that fund a large part of the cost of those products to consumers. Some jurisdictions operate 
positive and negative list systems under which products may only be marketed once a reimbursement price has been 
agreed. To obtain reimbursement or pricing approval, some of these countries may require the completion of clinical 
trials that compare the cost-effectiveness of a particular product candidate to currently available therapies. Other 
member states allow companies to fix their own prices for medicines but monitor and control company profits. The 
downward pressure on healthcare costs in general, particularly prescription drugs, has become very intense. As a 
result, increasingly high barriers are being erected to the entry of new products. In addition, in some countries, 
cross-border imports from low-priced markets exert a commercial pressure on pricing within a country. 

The marketability of any drug candidates for which we receive regulatory approval for commercial sale may suffer 
if the government and third-party payers fail to provide adequate coverage and reimbursement. In addition, emphasis 
on managed care in the United States has increased and we expect will continue to increase the pressure on 
pharmaceutical drug pricing. Coverage policies and third-party reimbursement rates may change at any time. Even if 
favorable coverage and reimbursement status is attained for one or more products for which we receive regulatory 
approval, less favorable coverage policies and reimbursement rates may be implemented in the future. 

Research and Development

Our research and development expenses were $94.9 million, $57.5 million and $40.5 million for the fiscal years 
ended September 30, 2018, 2017 and 2016, respectively.

Manufacturing 

We do not have our own manufacturing capabilities, except with respect to limited amounts of active pharmaceutical 
ingredients needed for preclinical development. In the past, we have relied on third-party manufacturers, including 
manufacturers in China, for supply of active pharmaceutical ingredients, and we expect that in the future we will 
rely on such manufacturers for the supply of ingredients that will be used in clinical trials of our product candidates 
that we are developing ourselves and to produce commercial quantities of any product candidates that we 
commercialize ourselves. Manufacturing for paritaprevir and glecaprevir are conducted by AbbVie. Wherever 
possible, we seek to identify multiple suppliers for raw materials and key intermediaries to be used in our 
manufacturing process. 

24

Sales and Marketing 

We currently do not have any commercialization or sales and marketing capabilities, and currently have no fixed 
plans to invest in or build such capabilities internally. We have partnered our protease inhibitor compounds for HCV 
with AbbVie. We may also partner or collaborate with, or license commercial rights to, other larger pharmaceutical 
or biopharmaceutical companies to support the development of one or more of our wholly-owned product candidates 
through late-stage clinical development and, if successful, commercialization. However, we still retain all 
commercial rights to our independent programs and we will continue to evaluate our alternatives for 
commercializing them once they are more advanced in their clinical development. 

Our Corporate Information

We are a Delaware corporation, incorporated in 1995. Our principal executive offices are located at 500 Arsenal 
Street, Watertown, Massachusetts 02472, and our telephone number is (617) 607-0800. Our web site address 
is www.enanta.com.

Segment Information

We provide segment information in Note 2 to our Consolidated Financial Statements included in Item 8 of this 
report. We are incorporating that information into this section by this reference.

Employees 

As of September 30, 2018, we had 113 full-time employees, 59 of whom hold Ph.D. or M.D. degrees. None of our 
employees are subject to a collective bargaining agreement or represented by a trade or labor union. We consider our 
relations with our employees to be good. 

Available Information

Our Internet website address is http://www.enanta.com. Through our website, we make available, free of charge, our 
annual report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and any amendments to 
those reports, as well as proxy statements, and, from time to time, other documents as soon as reasonably practicable 
after we electronically file such material with, or furnish it to, the Securities and Exchange Commission, or SEC. 
These SEC reports can be accessed through the “Investors” section of our website. The information found on our 
website is not part of this or any other report we file with or furnish to the SEC.

Investors may read and copy any materials we file with the SEC at the SEC’s Public Reference Room at 100 F 
Street, NE, Washington, DC 20549. You may obtain information on the operation of the Public Reference Room by 
calling the SEC at 1-800-SEC-0330. The SEC also maintains an Internet website that contains reports, proxy and 
information statements, and other information regarding Enanta Pharmaceuticals, Inc. and other issuers that file 
electronically with the SEC. The SEC’s Internet website address is http://www.sec.gov.

25

 
ITEM 1A.

RISK FACTORS 

RISK FACTORS 

Our business faces significant risks and uncertainties. Certain factors may have a material adverse effect on our 
business prospects, financial condition and results of operations, and you should carefully consider them. 
Accordingly, in evaluating our business, we encourage you to consider the following discussion of risk factors, in its 
entirety, in addition to other information contained in or incorporated by reference into this Annual Report on Form 
10-K and our other public filings with the SEC. Other events that we do not currently anticipate or that we currently 
deem immaterial may also affect our business, prospects, financial condition and results of operations.

Risks Related to Our Business 

Our financial prospects for the next several years are dependent upon the commercialization efforts of AbbVie 
for combination therapies incorporating our protease inhibitor, glecaprevir, for the treatment of HCV. AbbVie 
may act in its best interest rather than in our best interest, which could adversely affect our business.

We rely on AbbVie to fund and conduct the commercialization of its regimen containing glecaprevir (our second 
protease inhibitor, which is one of the two DAAs in AbbVie’s MAVYRET/MAVIRET treatment), over which we 
have granted AbbVie complete control. Our ability to generate revenue will depend primarily on the success of 
AbbVie’s continued efforts to commercialize MAVYRET/MAVIRET. Such success is subject to significant 
uncertainty, and we have no control over the resources, time and effort that AbbVie may devote to this regimen. 
Any of several events or factors could have a material adverse effect on our ability to generate revenue from 
AbbVie’s commercialization of glecaprevir in combination therapies. For example, AbbVie: 

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

may not achieve satisfactory levels of market acceptance and reimbursement by physicians, patients and 
third-party payers for the MAVYRET/MAVIRET regimen in the various markets of the world where it 
is being introduced and sold by AbbVie; 

may not compete successfully with its MAVYRET/MAVIRET regimen against other products and 
therapies for HCV; 

may have to comply with additional requests and recommendations from the FDA, including label 
restrictions for its regimen containing glecaprevir; 

may not make all regulatory filings and obtain all necessary approvals from foreign regulatory agencies 
and all commercially necessary reimbursement approvals; 

may not commit sufficient resources to the marketing and distribution of MAVYRET/MAVIRET, 
whether for competitive or strategic reasons or otherwise due to a change in business priorities; 

may cease to perform its obligations under the terms of our collaboration agreement; 

may unilaterally terminate our collaboration agreement on specified prior notice without any reason and 
without any further commitment; and

may not be able to manufacture paritaprevir or glecaprevir in compliance with requirements of the FDA 
and similar foreign regulatory agencies and in commercial quantities sufficient to meet market demand.

We do not have access to all information regarding the HCV regimens being commercialized by AbbVie, including 
certain information about spontaneous safety reports for any marketed product, regulatory affairs, process 
development, manufacturing, marketing, sales and other areas known by AbbVie. Thus, our ability to keep our 
stockholders informed about the status of products licensed under our collaboration is limited by the degree to which 
AbbVie keeps us informed. If AbbVie does not perform in the manner we expect or fulfill its responsibilities in a 
timely manner, or at all, the global commercialization of MAVYRET/MAVIRET could be delayed or terminated in 
selected jurisdictions or be commercially unsuccessful. In addition, AbbVie has the right to make decisions 
regarding the commercialization of licensed products without consulting us. For example, in November 2018, 
AbbVie entered into a royalty-free licensing agreement with the Medicines Patent Pool to accelerate access to 
AbbVie’s pan-genotypic HCV treatment glecaprevir/pibrentasvir (G/P) in 99 low- and middle-income countries and 

26

 
 
territories by granting World Health Organization prequalified generic manufacturers licenses to manufacture and 
supply generic versions of G/P for distribution in those countries. AbbVie may also make decisions with which we 
do not agree. If AbbVie acts in a manner that is not in our best interest, then it could adversely affect our business 
and prospects. 

Our royalty revenues are primarily derived from AbbVie’s net sales of its MAVYRET/MAVIRET regimen for 
HCV. If AbbVie is unable to maintain sales of this regimen at or above current levels of sales, our royalty 
revenues would be adversely affected.

Our quarterly royalty revenue from AbbVie’s net sales of its MAVYRET/MAVIRET regimen have grown 
substantially even as it is priced well below the pricing of AbbVie’s first HCV regimens, and below that of its 
principal competitor, Gilead. While commercialization of this regimen is exclusively in AbbVie’s control without 
any input from us, we believe it is possible that prices will decline further due to payers obtaining additional 
discounts or competitive market dynamics and that there may be fluctuation in AbbVie’s market share over time due 
to competitive actions by Gilead. We also note Gilead has reported a decline year over year across most major 
geographic markets in the number of new patients starting on DAA treatments for HCV.

In addition, in light of continued fiscal crises experienced by several countries in the European Union and Japan, 
governments have announced or implemented measures to manage and reduce healthcare expenditures. AbbVie may 
experience global pricing pressure for its HCV regimens from such measures, which may be reflected in larger 
discounts or rebates on its regimens or delayed reimbursement. Also, private and public payers may choose to 
exclude AbbVie’s MAVYRET/MAVIRET regimen from their formulary coverage lists or limit the types of patients 
for whom coverage will be provided. Any such change in formulary coverage, discounts or rebates or 
reimbursement for MAVYRET/MAVIRET would negatively affect the demand for such regimen and our royalty 
revenue derived from its sale.

We and AbbVie face substantial competition in the markets for HCV drugs, and there are many companies 
developing potential therapies for NASH, PBC, RSV and HBV, as well as other liver diseases and viral 
infections, which may result in others discovering, developing or commercializing products before we do or doing 
so more successfully than we do.

The pharmaceutical and biotechnology industries are intensely competitive and rapidly changing. Many large 
pharmaceutical and biotechnology companies, academic institutions, governmental agencies and other public and 
private research organizations are commercializing or pursuing the development of products that target HCV, 
NASH, PBC, RSV, HBV and other viral infections or liver diseases that we may target in the future. Many of our 
competitors have substantially greater commercial infrastructure and greater financial, technical and personnel 
resources than we have, as well as drug candidates in late-stage clinical development.

In all the disease areas currently under the focus of our research and development efforts, there are other companies 
with product candidates that are more advanced than ours. Our competitors may succeed in developing these product 
candidates or others and obtaining regulatory approval before we can do so with any of our product candidates. If 
we are not “first to market” with one of our product candidates in one or more of these disease indications, our 
competitive position could be compromised because it may be more difficult for us to obtain marketing approval for 
that product candidate and market acceptance of that product candidate as a follow-on competitor. In addition, any 
new product that competes with an approved product typically must demonstrate compelling advantages in efficacy, 
convenience, tolerability or safety, or some combination of these factors, in order to gain regulatory approvals, 
overcome price competition and be commercially successful.

We expect AbbVie’s MAVYRET/MAVIRET to continue to face intense competition due to existing approved 
products in the HCV market. AbbVie’s HCV treatment regimens currently face competition in various world 
markets and subpopulations of HCV from Gilead’s Epclusa® (a fixed dose combination of sofosbuvir and 
velpatasvir), Vosevi™ (a triple combination therapy of sofosbuvir, velpatasvir and voxilaprevir approved by the 
FDA in July 2017 for specified sofosbuvir -treatment failures and NS5A-inhibitor treatment failures) and 
Harvoni® (a fixed-dose combination of sofosbuvir and ledipasvir); and to a lesser extent - Merck’s Zepatier® (a 
fixed-dose combination of grazoprevir and elbasvir). Recently, Gilead announced plans to launch authorized generic 
versions of Epclusa and Harvoni in January 2019 through a newly created subsidiary, Asegua Therapeutics, LLC. 
Competitive products in the form of other treatment methods or a vaccine for HCV may render AbbVie’s HCV 

27

regimens obsolete or noncompetitive. AbbVie’s regimens that contain one of our collaboration’s protease inhibitors 
will face competition based on their safety and effectiveness, reimbursement coverage, price, patent position, 
AbbVie’s marketing and sales capabilities, and other factors. If any of AbbVie’s HCV regimens face competition 
from generic products, the collaboration agreement provides that the royalty rate applicable to our protease product 
contained in the regimen is reduced significantly by a specified percentage on a product-by-product, country-by-
country basis. If AbbVie is not able to compete effectively against its competitors in HCV, our business will not 
grow and our financial condition, operations and stock price will suffer.

We also expect our other product candidates to face intense and increasing competition in the NASH and antiviral 
markets as advanced technologies and products become available. Though there is currently no approved treatment 
for NASH, we expect significant competition from other companies in the development of new treatments for 
NASH and related conditions. We are aware of several companies with NASH programs that are significantly more 
advanced than ours, including companies with compounds in Phase 3 clinical trials in NASH, namely Intercept, 
Genfit, Gilead, and Tobira (Allergan). In May 2016, the FDA granted conditional approval for Intercept’s FXR 
agonist (brand name Ocaliva®) for the treatment of primary biliary cholangitis (PBC) in combination with first line 
therapy ursodeoxycholic acid (UDCA) in adults with an inadequate response to UDCA, or as monotherapy in adults 
unable to tolerate UDCA. In addition, a number of companies have NASH or related programs with compounds in 
Phase 2 clinical trials. These companies include Alberio, Astra-Zeneca, BMS, Boehringer Ingelheim, Can-Fite 
BioPharma, Conatus, Cirius, Cymabay, Galectin, Galmed, Gemphire Therapeutics, Gilead, GlaxoSmithKline, 
Immuron, Inventiva, Madrigal, Medicinova, Northsea Therapeutics, Novartis, NGM, Novo Nordisk, Pfizer and 
Viking. A significant number of other companies are conducting earlier stage clinical trials that may be applicable in 
NASH and other cholestatic diseases. There are also additional companies conducting preclinical studies in these 
disease areas.

Similarly, HBV and RSV represent competitive therapeutic areas. While there are effective antiviral medications 
prescribed for HBV, they generally have low true cure rates. Many companies are seeking to develop new HBV 
drugs that alone or in combination with other mechanisms could lead to a functional cure of HBV. Arbutus, Gilead, 
HEC, Ionis, Johnson & Johnson, Maxwell, Replicor, Roche and Spring Bank have Phase 2 programs in progress, 
with many of these companies conducting earlier stage programs as well. In addition, a number of companies have 
Phase 1 or earlier stage HBV programs, including Aicuris, Alnylam, Altimmune, Assembly, Arrowhead, Enyo and 
Transgene. 

For RSV, there are currently no safe and effective therapies for already established RSV infection. Several 
companies are seeking new antiviral treatments for RSV infection in adult and pediatric settings. Ark Bioscienes, 
Johnson & Johnson, Gilead, Pulmocide and ReViral each have compounds in clinical development, as does Ablynx 
with a potential therapeutic antibody. A prophylactic, monoclonal-antibody-based treatment from MedImmune, 
which is commercialized by AbbVie outside of the U.S., is approved for infants considered at high risk for RSV 
infection; however studies have found that most young children with RSV infection were previously healthy, and 
thus would not normally be prescribed prophylactic treatment. In addition, a number of companies have RSV 
vaccines in development, primarily directed at prevention of RSV infection, and some companies are also evaluating 
vaccines in a therapeutic mode for treatment of established RSV infection.

If we are not able to develop new products that can compete effectively against our current and future competitors, 
our business will not grow and our financial condition, operations and stock price will suffer.

28

We have not developed independently any approved products and we have limited clinical development 
experience, which makes it difficult to assess our ability to develop and commercialize our product candidates.

AbbVie has been responsible for all of the clinical development of our paritaprevir and glecaprevir protease 
inhibitor products. We have not yet demonstrated an ability to address successfully many of the risks and 
uncertainties associated with late stage clinical development, regulatory approval and commercialization of 
therapeutic products such as the ones we plan to develop independently. For example, to execute our business plan 
for development of our independent RSV, NASH, PBC and HBV programs, we will need to successfully: 

(cid:129)

(cid:129)

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(cid:129)

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(cid:129)

(cid:129)

execute clinical development of our product candidates and demonstrate acceptable safety and efficacy 
for them alone or in combination with other drugs or drug candidates; 

obtain required regulatory approvals for the development and commercialization of our product 
candidates;

develop and maintain any future collaborations we may enter into for any of these programs; 

obtain and maintain patent protection for our product candidates and freedom from infringement of 
intellectual property of others; 

establish acceptable commercial manufacturing arrangements with third-party manufacturers;

build and maintain robust sales, distribution and marketing capabilities, either independently or in 
collaboration with future collaborators; 

gain market acceptance for our product candidates among physicians, payers and patients; and 

manage our spending as costs and expenses increase due to clinical trials, regulatory approvals and 
commercialization. 

If we are unsuccessful in accomplishing these objectives, we may not be able to successfully develop and 
commercialize our product candidates and expand our business or continue our operations.

If we are not successful in developing EDP-305, EDP-938 and/or EDP-514 or in discovering further product 
candidates in addition to those product candidates, our ability to expand our business and achieve our strategic 
objectives will be impaired. 

Much of our internal research is at preclinical stages. Research programs designed to identify product candidates 
require substantial technical, financial and human resources, whether or not any product candidates are ultimately 
identified. Our research programs may initially show promise in identifying additional potential product candidates, 
yet fail to yield product candidates for clinical development or commercialization for many reasons, including the 
following:

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(cid:129)

(cid:129)

the research methodology used may not be successful in identifying additional potential product 
candidates; 

competitors may develop alternatives that render our product candidates less commercially viable or 
obsolete; 

competitors may obtain intellectual property protection that effectively prevents us from developing a 
product candidate;

a product candidate may, on further study, be shown not to be an effective treatment in humans or to 
have harmful side effects or other characteristics that indicate it is unlikely to be effective or otherwise 
does not meet applicable regulatory criteria; and

a product candidate may not be capable of being produced in commercial quantities at an acceptable 
cost, or at all.

29

Additional drug candidates that we may develop will require significant research, preclinical and clinical studies, 
regulatory approvals and commitments of resources before they can be commercialized. We cannot give assurance 
that our research will lead to the discovery of any additional drug candidates that will generate additional revenue 
for us. If we are unable to identify additional compounds suitable for preclinical and clinical development, we may 
not be able to obtain sufficient product revenue in future periods, which likely would result in significant harm to 
our financial position and adversely impact our stock price. 

Expenses associated with development of our product candidates may cause our results of operations to fluctuate 
from period to period, which may result in operating losses.

Many of the preclinical and clinical development activities required for our product candidates must be contracted 
out to contract research organizations (CROs) at significant expense. We expect these expenses to increase 
substantially in the coming years as we advance compounds and conduct more clinical studies. It is difficult to 
accurately predict the timing and amounts of these expenses, and we expect that they will vary from quarter to 
quarter. In addition, the FDA or other regulatory agencies may require more preclinical or clinical testing than we 
originally anticipated for any of our product candidates. We may also be required to purchase expensive competitor 
drugs for use in our trials, either to demonstrate potential treatment combinations or as comparators to our product 
candidates. We also conduct clinical development activities outside the U.S. and are therefore exposed to foreign 
currency fluctuations for payments made to CROs in currencies other than the U.S. dollar. As a result, the expenses 
of our development programs and our operating results may fluctuate significantly from quarter to quarter, and our 
stock price may be adversely affected.

If we fail to attract and keep senior management and key scientific personnel, we may be unable to successfully 
develop our product candidates, conduct our clinical trials and commercialize our product candidates.

Our success depends in part on our continued ability to attract, retain and motivate highly qualified management, 
clinical and scientific personnel. We are highly dependent upon our senior management, particularly Jay R. Luly, 
Ph.D., our Chief Executive Officer and President, Yat Sun Or, Ph.D., our Senior Vice President, Research and 
Development and Chief Scientific Officer, and Nathalie Adda, M.D., our Senior Vice President, Chief Medical 
Officer, as well as other employees and consultants. Although none of these individuals has informed us to date that 
he or she intends to retire or resign in the near future, the loss of the services of any of these individuals or one or 
more of our other members of senior management could delay or prevent the successful development of our product 
candidates.

Although we have not historically experienced unique difficulties attracting and retaining qualified employees, we 
could experience such problems in the future. For example, competition for qualified personnel in the biotechnology 
and pharmaceutical fields is intense. In addition, we will need to hire additional personnel as we expand our clinical 
development and ultimately seek regulatory approvals and prepare for commercial activities. We may not be able to 
attract and retain quality personnel on acceptable terms. 

We may encounter difficulties in managing our growth and expanding our operations successfully.

As we expand our research efforts and seek to advance our product candidates through clinical trials, we will need to 
expand our development, regulatory, manufacturing, marketing and sales capabilities or contract with third parties to 
provide these capabilities for us. As our operations expand, we expect that we will need to manage additional 
relationships with various strategic partners, suppliers and other third parties. Future growth will impose significant 
added responsibilities on members of management. Our future financial performance and our ability to 
commercialize our product candidates and to compete effectively will depend, in part, on our ability to manage any 
future growth effectively. To that end, we must be able to manage our development efforts and clinical trials 
effectively and hire, train and integrate additional management, administrative and sales and marketing personnel. 
We may not be able to accomplish these tasks, and our failure to accomplish any of them could prevent us from 
successfully growing our company.

30

To date, our principal sources of revenue have been our collaboration agreements, including our current 
agreement with AbbVie. Future levels of royalties under the AbbVie agreement are uncertain. We have had no 
other products approved for commercial sale by us. Therefore, it is possible that we may incur operating losses in 
one or more years in the future, and our ability to achieve sustained profitability is unproven.

In each of our past four fiscal years, our net income resulted primarily from license payments, including milestone 
payments we earned from AbbVie and royalties we earned since December 2014 on net sales of AbbVie’s HCV 
regimens allocated to our protease inhibitors included in those regimens. There is no assurance, however, that we 
will report net income in subsequent years. To date, we have not commercialized any products ourselves.

Our principal source of revenue historically has been our collaboration agreements, including our current agreement 
with AbbVie. The level of future royalties on products containing paritaprevir or glecaprevir is uncertain given the 
competitive nature of the market for HCV therapies. This is attributed to price competition, the changing nature of 
payer contracts of AbbVie and others, and the varying rates of reimbursement in different countries. At any time, 
AbbVie may choose not to continue its commercialization activities for the MAVYRET/MAVIRET regimen. If we 
are unable to develop and commercialize any more of our product candidates, either alone or with a collaborator, or 
if any such product candidate does not achieve market acceptance, we may not generate sufficient product sales or 
product royalties. In addition, for any of our product candidates included in a treatment regimen with more than one 
active compound, it would be uncertain what portion of net sales of the regimen would be allocated to our product 
candidate. Even if we do generate significant product royalties or product sales, we may not be able to sustain 
profitability on a quarterly or annual basis. Our failure to sustain profitability could depress the market price of our 
common stock and ultimately could impair our ability to raise capital, expand our business, diversify our product 
offerings or continue our operations. A decline in the market price of our common stock also could cause you to lose 
all or a part of your investment.

We may require substantial additional financing in the longer term to achieve our goals if the further 
commercialization of MAVYRET/MAVIRET is not successful. A failure to obtain this necessary capital when 
needed could force us to delay, limit, reduce or terminate some or all of our product development efforts.

Since our inception, most of our resources have been dedicated to the discovery and preclinical development of our 
product candidates. In particular, we have expended, and believe that we will continue to expend for the foreseeable 
future, substantial resources discovering and developing our proprietary product candidates. These expenditures will 
include costs associated with research and development, preclinical manufacturing of product candidates, 
conducting preclinical experiments and clinical trials and obtaining regulatory approvals, as well as commercializing 
any products later approved for sale. For the foreseeable future, we expect to incur substantial additional costs 
associated with research and development for our internally developed programs, exclusive of costs incurred by 
AbbVie in developing MAVYRET/MAVIRET. In addition, we may seek opportunities to in-license or otherwise 
acquire new therapeutic candidates and therapies.

Our future capital requirements depend on many factors, including:

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whether our existing collaboration continues to generate substantial royalties to us;

the number and characteristics of the product candidates we pursue; 

the scope, progress, results and costs of researching and developing any of our product candidates on 
our own, including conducting preclinical research and clinical trials; 

opportunities to in-license or otherwise acquire new therapeutic candidates and therapies;

the timing, receipt and amount of royalties on paritaprevir and glecaprevir and any sales of our product 
candidates, if any, or royalties thereon;

the timing of, and the costs involved in, obtaining regulatory approvals for any product candidates we 
develop independently;

the cost of commercialization activities, if any, of any product candidates we develop independently that 
are approved for sale, including marketing, sales and distribution costs;

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the cost of manufacturing our product candidates and any products we successfully commercialize 
independently, including manufacturing for clinical development;

our ability to maintain our existing collaboration and to establish new collaborations, licensing or other 
arrangements and the financial terms of such agreements; and

the costs involved in preparing, filing, prosecuting, maintaining, defending and enforcing patents, 
including any litigation costs and the outcomes of any such litigation.

Additional funds may not be available if and when we need them, on terms that are acceptable to us, or at all. Our 
ability to raise funds will depend on financial, economic and market conditions and other factors, many of which are 
beyond our control. If adequate funds are not available to us on a timely basis, we may be required to delay, limit, 
reduce or terminate preclinical studies, clinical trials or other research and development activities for one or more of 
our product candidates. 

The U.S. Tax Cuts and Jobs Act enacted in December 2017 includes significant changes from prior tax law 
which could result in significant changes to our future tax positions.  

The U.S. Tax Cuts and Jobs Act (the “Tax Act”) enacted in December 2017 contains many provisions which differ 
from prior tax law. These changes include, but are not limited to, the reduction in the federal corporate income tax 
rate from 35% to 21%, the elimination of a corporation’s ability to carryback net operating losses to prior taxable 
income periods and the elimination of the deductibility of certain performance-based equity awards under Section 
162(m). We accounted for the Tax Act during the year ended September 30, 2018 , which resulted in an adjustment 
that decreased our deferred tax assets by $3.8 million due to the reduction of the federal corporate income tax rate 
from 35% to 21%. Estimates used to prepare our income tax expense are based on our analysis of the Tax 
Act. Given the complexity of the act, anticipated guidance from the U.S. Treasury regarding implementation of the 
Tax Act, and potential for guidance from the Securities and Exchange Commission or the Financial Accounting 
Standards Board related to the act, these estimates may be adjusted in future periods to reflect any such guidance 
provided. 

Risks Related to Development, Clinical Testing and Regulatory Approval of Our Product Candidates

Clinical drug development involves a lengthy and expensive process with uncertain timelines and uncertain 
outcomes. If clinical trials of any of our proprietary product candidates are prolonged or delayed, we may be 
unable to commercialize our product candidates on a timely basis.

Clinical testing is expensive and, depending on the stage of development, can take a substantial time period to 
complete. Its outcome is inherently uncertain, and failure can occur at any time during clinical development. None 
of our product candidates in our pipeline other than paritaprevir and glecaprevir, which have been clinically 
developed by AbbVie, has yet to advance beyond completion of Phase 2 clinical trials. Any future clinical trials of 
our product candidates may fail to demonstrate sufficient safety and efficacy. Moreover, regulatory and 
administrative delays for any product candidate in our pipeline may adversely affect our or any future collaborator’s 
clinical development plans and jeopardize our or any future collaborator’s ability to attain product approval, 
commence product sales and compete successfully against other therapies. 

Clinical trials can be delayed for a variety of reasons, including delays related to: 

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reaching an agreement on acceptable terms with prospective contract research organizations, or CROs, 
and clinical trial sites, the terms of which can be subject to extensive negotiation and may vary 
significantly among different CROs and trial sites; 

failure of third-party contractors, such as CROs, or investigators to comply with regulatory 
requirements;

delay or failure in obtaining the necessary approvals from regulators or institutional review boards, or 
IRBs, in order to commence a clinical trial at a prospective trial site, or their suspension or termination 
of a clinical trial once commenced;

difficulty in recruiting suitable patients to participate in a trial;

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difficulty in having patients complete a trial or return for post-treatment follow-up;

clinical sites deviating from trial protocol or dropping out of a trial;

problems with drug product or drug substance storage and distribution;

adding new clinical trial sites;

our inability to manufacture, or obtain from third parties, adequate supply of drug product sufficient to 
complete our preclinical studies and clinical trials;

governmental or regulatory delays and changes in regulatory requirements, policy and guidelines, 
including guidelines specifically addressing requirements for the development of treatments for RSV, 
NASH, PBC or HBV;

program discontinuations or clinical holds for a program of a competitor, which could increase the level 
of regulatory scrutiny or delay data review or other response times by regulators with respect to one of 
our programs in the same class as the competitor’s program; or

varying interpretations of data by the FDA, the EMA and similar foreign regulatory agencies.

We could also encounter delays if a clinical trial is suspended or terminated by us, by the IRBs of the institutions in 
which such trial is being conducted, by any Data Safety Monitoring Board, or DSMB, for such trial, or by the FDA, 
the EMA or other regulatory authorities. Such authorities may impose such a suspension or termination due to a 
number of factors, including failure to conduct the clinical trial in accordance with regulatory requirements or our 
clinical protocols, inspection of the clinical trial operations or trial site by the FDA or other regulatory authorities 
resulting in the imposition of a clinical hold, unforeseen safety issues or adverse side effects, failure to demonstrate 
a benefit from using a drug, changes in governmental regulations or administrative actions or lack of adequate 
funding to continue the clinical trial. In addition, delays can occur due to safety concerns arising from trials or other 
clinical data regarding another company’s product candidate in the same compound class as one of ours. If we or 
any future collaborators experience delays in the completion of, or termination of, any clinical trial of one of our 
product candidates, the commercial prospects of the product candidate will be harmed, and our ability to commence 
product sales and generate product revenues from the product candidate will be delayed. In addition, any delays in 
completing our clinical trials will increase our costs and slow down our product candidate development and 
approval process. Any of these occurrences may harm our business, financial condition and prospects significantly. 
In addition, many of the factors that cause, or lead to, a delay in the commencement or completion of clinical trials 
may also ultimately lead to the denial of regulatory approval of our product candidates.

We may choose to test any of our clinical candidates preclinically and/or clinically in combination with other 
compounds with different mechanisms of action, and any adverse results from such testing may have adverse 
consequences for the further development potential of not only the combination but also the clinical candidate 
itself as a monotherapy or in combination with other mechanisms of action.

We expect that the further development of successful therapies in our principal disease areas of RSV, NASH and 
HBV may require combining one or more of our compounds with other compounds with different mechanisms of 
action. To advance our programs and achieve favorable opportunities for any such combinations we may conduct 
preclinical testing, as well as clinical testing, with one of our other compounds or with a compound of a third party, 
with or without a longer-term collaboration with any such party. We may choose to disclose such testing in advance, 
but we can anticipate that some of the testing would be done without any public disclosure. If any such testing 
produces adverse results, we may have to disclose it to regulatory authorities as part of the data available with 
respect to our product candidate and the data may have adverse consequences for the further development and the 
ultimate conditions attached to any approved use of the product candidate, whether in the combination tested or even 
as a monotherapy or in combination with other mechanisms. 

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EDP-305, EDP-938, EDP-514 or any other product candidate emerging from our current NASH, PBC, RSV and 
HBV programs may have undesirable side effects which may delay or prevent marketing approval, or, if approval 
is received, require our product candidate to be taken off the market, require us to include safety warnings or 
otherwise limit sales. 

In our NASH/PBC program, we are developing agonists of the farnesoid X receptor, or FXR, that are designed to 
bind to that receptor and then trigger a response from it. The adverse effects from long-term exposure to the FXR 
drug class are not well known since within this class only two drugs have been approved by the FDA—Ocaliva®, 
approved in May 2016 for PBC, and an older drug not commonly used but approved to treat cholesterol gallstones 
(by dissolving them) and a rare lipid storage disease. Unforeseen side effects from any of our product candidates 
could arise either during clinical development or, if approved, after the approved product has been marketed. The 
range and potential severity of possible side effects from systemic therapies like FXR agonists could be significant.

In addition, our drug candidates for NASH may be developed as a potential treatment for a severe disease that 
commonly occurs in patients with other serious conditions, including metabolic syndrome and diabetes. Any clinical 
trials in NASH will necessarily be conducted in patient populations that may be more prone than the general 
population to exhibit certain disease states or adverse events. It may be difficult to discern whether certain events or 
symptoms observed during our trials were due to our drug candidates or placebo, resulting in our company and our 
development programs being negatively affected even if such events or symptoms are ultimately determined to be 
unlikely related to our drug candidates.

In our RSV program, we are developing inhibitors of the N protein. No inhibitor of the RSV N protein has 
progressed beyond a Phase 2 clinical trial, so we are not yet able to assess the potential liabilities of an N inhibitor in 
large scale studies or in the general population. In addition, in RSV the principal target populations, namely infants, 
the elderly, and the immunocompromised, represent sensitive patient populations that could be more prone to 
adverse effects of therapy.

In our HBV program, we are developing modulators of capsid assembly. This is a new mechanistic approach to 
HBV, and no capsid assembly modulators have advanced beyond Phase 2 clinical studies. Thus, we are not able to 
predict what adverse effects may arise in longer term studies conducted in larger populations. In addition, in HBV, 
long term consequences of an HBV infection can include hepatocellular carcinoma, liver failure, or liver 
transplant. It may be difficult to determine whether our drug candidates are playing a direct role in contributing to 
(or protecting from) these downstream effects of HBV infection.

If any of our product candidates receives marketing approval and we or others later identify undesirable or 
unacceptable side effects caused by such products: 

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regulatory authorities may require the addition of labeling statements, specific warnings, a 
contraindication or field alerts to physicians and pharmacies; 

we may be required to change instructions regarding the way the product is administered, conduct 
additional clinical trials or change the labeling of the product; 

we may be subject to limitations on how we may promote the product; 

sales of the product may decrease significantly; 

regulatory authorities may require us to take our approved product off the market; 

we may be subject to litigation or product liability claims; and 

our reputation and our stock price may suffer. 

Any of these events could prevent us from achieving or maintaining market acceptance of the affected product or 
could substantially increase commercialization costs and expenses, which in turn could delay or prevent us from 
generating significant revenue from the sale of any product we develop.

34

 
If we are required to suspend or discontinue clinical trials due to side effects or other safety risks associated with 
our product candidates, or if we are required to conduct studies on the long-term effects associated with the use 
of any of those product candidates, commercialization any of those product candidates could be delayed or 
halted.

Clinical trials involving our product candidates may be suspended or terminated at any time for a number of safety-
related reasons. For example, we may voluntarily suspend or terminate clinical trials if at any time one of our 
product candidates, or a combination therapy including any of them, presents an unacceptable safety risk to the 
clinical trial patients. In addition, IRBs or regulatory agencies may order the temporary discontinuation or 
termination of clinical trials at any time if they believe that the clinical trials are not being conducted in accordance 
with applicable regulatory requirements, including if they present an unacceptable safety risk to patients. 
Administering any product candidate to humans may produce undesirable side effects. The existence of undesirable 
side effects resulting from any of our product candidates, or a combination therapy including any of them, could 
cause us or regulatory authorities, such as the FDA or EMA, to interrupt, delay or halt clinical trials of our product 
candidates and could result in the FDA or EMA or other regulatory agencies denying further development or 
approval of our product candidates for any or all targeted indications. This, in turn, could prevent us from 
commercializing our product candidates.

Results of earlier clinical trials may not be predictive of the results of later-stage clinical trials.

The results of preclinical studies and early clinical trials of our product candidates may not be predictive of the 
results of later-stage clinical trials, if any. In addition, results of Phase 3 clinical trials in one or more ethnic groups 
are not necessarily indicative of results in other ethnic groups. Product candidates in later stages of clinical trials 
may fail to show the desired safety and efficacy results despite having progressed through preclinical studies and 
initial clinical trials. Many companies in the biopharmaceutical industry have suffered significant setbacks in 
advanced clinical trials due to adverse safety profiles or lack of efficacy, notwithstanding promising results in earlier 
studies. Similarly, future clinical trial results may not be successful for these or other reasons.

Product candidate development risk is heightened by any changes in the planned clinical trials compared to the 
completed clinical trials. As product candidates are developed through preclinical early and late stage clinical trials 
towards approval and commercialization, it is customary that various aspects of the development program, such as 
manufacturing and formulation, are altered along the way in an effort to optimize processes and results. Such 
changes carry the risk that they will not achieve these intended objectives. Any of these changes could make the 
results of planned clinical trials or other future clinical trials we may initiate less predictable and could cause our 
product candidates to perform differently, which could delay completion of clinical trials, delay approval of our 
product candidates and/or jeopardize our ability to commence product sales and generate revenues.

The regulatory approval processes of the FDA, the EMA and other comparable foreign authorities are lengthy, 
time-consuming and inherently unpredictable, and if we are ultimately unable to obtain timely regulatory 
approval for our product candidates, our business will be substantially harmed.

The regulatory approval process is expensive and, while the time required to gain FDA and foreign regulatory 
approval is uncertain, it may take years. Regulatory approvals are unpredictable and depend upon numerous factors, 
including the substantial discretion of the regulatory authorities. In addition, approval policies, regulations, or the 
type and amount of preclinical and clinical data necessary to gain approval may change during the course of a 
product candidate’s clinical development and may vary among jurisdictions. We may be required to undertake and 
complete certain additional preclinical studies to generate toxicity and other data required to support the submission 
of a New Drug Application, or NDA, to the FDA or comparable application to other regulatory authorities. AbbVie 
obtained all regulatory approvals for its paritaprevir-containing regimens and for MAVYRET/MAVIRET, which 
contains glecaprevir. We have not obtained regulatory approval by ourself for any of our wholly-owned product 
candidates and it is possible that none of our existing product candidates or any of our future product candidates will 
ever obtain regulatory approval. Furthermore, approval in the United States by the FDA does not ensure approval by 
regulatory authorities in other countries or jurisdictions, and approval by one foreign regulatory authority does not 
ensure approval by regulatory authorities in other foreign countries or by the FDA.

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Our product candidates could fail to receive regulatory approval for many reasons, including the following: 

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the FDA, the EMA or other comparable foreign regulatory authorities may disagree with the design or 
implementation of our clinical trials;

we may be unable to demonstrate to the satisfaction of the FDA, the EMA or other comparable foreign 
regulatory authorities that a product candidate is safe and effective for its proposed indication;

the results of clinical trials may not meet the level of statistical significance required by the FDA, the 
EMA or other comparable foreign regulatory authorities for approval;

we may be unable to demonstrate that a product candidate’s clinical and other benefits outweigh its 
safety risks;

the FDA, the EMA or other comparable foreign regulatory authorities may disagree with our 
interpretation of data from preclinical studies or clinical trials; 

the data collected from clinical trials of our product candidates may not be sufficient to support the 
submission of an NDA or other submissions or to obtain regulatory approval in the United States or 
elsewhere; 

the FDA or comparable foreign regulatory authorities may fail to approve the manufacturing processes 
or facilities of third-party manufacturers with which we contract for clinical and commercial supplies of 
any of our product candidates; and 

the approval policies or regulations of the FDA, the EMA or other comparable foreign regulatory 
authorities may significantly change in a manner rendering our clinical data insufficient for approval. 

We cannot be assured that after spending substantial time and resources, we will obtain regulatory approvals in any 
desired jurisdiction. Even if we were to obtain approval, regulatory authorities may grant approval contingent on the 
performance of costly post-marketing clinical trials, or may approve a product candidate with a label that does not 
include the labeling claims necessary or desirable for the successful commercialization of that product candidate. 
Significant clinical trial delays could allow our competitors to obtain marketing approval before we do or could in 
effect shorten the patent protection period during which we may have the exclusive right to commercialize our 
product candidates. In addition, it may ultimately not be possible to achieve the prices intended for our products. In 
many foreign countries, including those in the European Union, a product candidate must be approved for 
reimbursement before it can be approved for sale in that country. Any of the foregoing scenarios could materially 
harm the commercial prospects for our product candidates and our business.

Even if we receive regulatory approval for any of our product candidates we develop independently, we will be 
subject to ongoing FDA obligations and continued regulatory review in other jurisdictions, which may result in 
significant additional expense. Additionally, our product candidates, if approved, could be subject to labeling and 
other restrictions and market withdrawal and we may be subject to penalties if we or our collaborators fail to 
comply with regulatory requirements or experience unanticipated problems with our products.

Any regulatory approvals that we receive for our product candidates we develop independently may be subject to 
limitations on the approved indicated uses for which the product may be marketed or subject to certain conditions of 
approval, or may contain requirements for potentially costly post-marketing testing, including Phase 4 clinical trials, 
and surveillance to monitor the safety and efficacy of the product candidate.

36

In addition, if the FDA approves any of our product candidates, the manufacturing processes, labeling, packaging, 
distribution, adverse event reporting, storage, advertising, promotion and recordkeeping for the product will be 
subject to extensive and ongoing regulatory requirements. These requirements include submissions of safety and 
other post-marketing information and reports, as well as continued compliance with current good manufacturing 
practices, or cGMP, and good clinical practices, or GCP, for any clinical trials that we or our collaborators conduct 
post-approval. Later discovery of previously unknown problems with a product, including adverse events of 
unanticipated severity or frequency, or with third-party manufacturers or manufacturing processes, or failure to 
comply with regulatory requirements, may result in, among other things: 

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restrictions on the marketing or manufacturing of the product, withdrawal of the product from the 
market or voluntary or mandatory product recalls; 

fines, warning letters or holds on any post-approval clinical trials; 

refusal by the FDA to approve pending applications or supplements to approved applications filed by us, 
or suspension or revocation of product license approvals; 

product seizure or detention, or refusal to permit the import or export of products; and 

injunctions or the imposition of civil or criminal penalties. 

We cannot predict the likelihood, nature or extent of government regulation that may arise from future legislation or 
administrative action, either in the United States or abroad. If we, or AbbVie in the case of any licensed HCV 
product, are slow or unable to adapt to changes in existing requirements or the adoption of new requirements or 
policies, or if we or AbbVie are not able to maintain regulatory compliance, our product candidates or AbbVie’s 
licensed HCV products may lose any marketing approval that may have been obtained and we may not achieve or 
sustain profitability, which would adversely affect our business. 

We may delay or terminate the development of a product candidate at any time if we believe the perceived market 
or commercial opportunity does not justify further investment, which could materially harm our business and 
adversely affect our stock price. 

Even though the results of preclinical studies and clinical trials that we have conducted or may conduct in the future 
may support further development of one or more of our product candidates, we may delay, suspend or terminate the 
future development of a product candidate at any time for strategic, business, financial or other reasons, including 
the determination or belief that the emerging profile of the product candidate is such that it may not receive 
regulatory approvals in key markets, gain meaningful market acceptance, otherwise provide any competitive 
advantages in its intended indication or market or generate a significant return to stockholders. Such a delay, 
suspension or termination could materially harm our business, results of operations or financial condition. In 
addition, AbbVie has the right to make decisions regarding the commercialization of paritaprevir and glecaprevir 
without consulting us, and may make decisions with which we do not agree. 

Risks Related to Commercialization of Our Product Candidates 

Even if AbbVie continues to successfully commercialize MAVYRET/MAVIRET, or even if we are able to 
commercialize any other treatment regimen containing one of our product candidates from any of our 
proprietary discovery programs, MAVYRET/MAVIRET or the resulting products, as the case may be, may 
become subject to unfavorable pricing regulations, third-party reimbursement practices or healthcare reform 
initiatives in the United States, which would harm our business.

The regulations that govern marketing approvals, pricing and reimbursement for new drug products vary widely 
from country to country. In the United States, the Patient Protection and Affordable Care Act, as amended by the 
Health Care and Education Affordability Reconciliation Act of 2010, collectively referred to as the ACA, is 
significantly changing the way healthcare is financed by both governmental and private insurers. While we cannot 
predict what impact on federal reimbursement policies this law or any amendment to it will continue to have in 
general or specifically on any product or regimen that we may commercialize, the ACA or any such amendment 
may result in downward pressure on pharmaceutical reimbursement, which could negatively affect market 
acceptance of new products. In addition, although the United States Supreme Court has upheld the constitutionality 

37

of most of the ACA, several states have not implemented certain sections of the ACA, including 14 that have 
rejected the expansion of Medicaid eligibility for low income citizens, and some members of the U.S. Congress are 
still working to repeal the ACA. More recently, President Trump and the Republicans in both houses of the U.S. 
Congress have been seeking to repeal or replace all or portions of the ACA but to date they have been unable to 
agree on any such legislation. We cannot predict what legislation, if any, to repeal or replace the ACA will become 
law, or what impact any such legislation may have on us or on AbbVie’s commercialization of its HCV regimens.

Our ability to commercialize any product candidate successfully, as well as AbbVie’s commercialization of 
MAVYRET/MAVIRET, will also depend in part on the extent to which reimbursement for these products and 
related treatments will be available from government health administration authorities, private health insurers and 
other organizations. Government authorities and third-party payors, such as private health insurers and health 
maintenance organizations, decide which medications they will pay for and establish reimbursement levels. A 
primary trend in the U.S. healthcare industry is cost containment. Government authorities and third-party payors 
have attempted to control costs by limiting coverage and the amount of reimbursement for particular medications. In 
the case of HCV, limitations of coverage have recently been used to limit access to HCV treatments for only those 
patients with more advanced fibrosis. Increasingly, third-party payors are requiring that drug companies provide 
them with predetermined discounts from list prices and, in many cases involving HCV drugs, seeking discounts in 
exchange for greater patient access to a particular HCV drug. In addition, there are private and public payors 
challenging the prices charged for medical products. We cannot be sure that reimbursement will be available for any 
product that we may commercialize and, if reimbursement is available, the level of reimbursement. In addition, 
reimbursement may impact the demand for, or the price of, MAVYRET/MAVIRET or any product candidate for 
which we may obtain marketing approval. If reimbursement is not available or is available only to limited levels, 
AbbVie may not be successful in commercializing MAVYRET/MAVIRET and we may not be able to successfully 
commercialize any product candidate for which we may seek marketing approval.

There may be significant delays in obtaining reimbursement for newly approved drugs, and coverage may be more 
limited than the purposes for which the drug is approved by the FDA or comparable authorities in other 
jurisdictions. Moreover, eligibility for reimbursement does not imply that any drug will be paid for in all cases or at 
a rate that covers our costs, including research, development, manufacture, sale and distribution. Interim 
reimbursement levels for new drugs, if applicable, may also be insufficient to cover our and any collaborator’s costs 
and may not be made permanent. Reimbursement rates may vary according to the use of the drug and the clinical 
setting in which it is used, may be based on reimbursement levels already set for lower cost drugs and may be 
incorporated into existing payments for other services. Net prices for drugs may be reduced by mandatory discounts 
or rebates required by government healthcare programs or private payors and by any future relaxation of laws that 
presently restrict imports of drugs from countries where they may be sold at lower prices than in the United States. 
Third-party payors often rely upon Medicare coverage policy and payment limitations in setting their own 
reimbursement policies. AbbVie’s inability to promptly obtain coverage and profitable payment rates from both 
government-funded and private payors for MAVYRET/MAVIRET, or our inability to do the same for any product 
candidate that we develop, could have a material adverse effect on our operating results, our ability to raise capital 
needed to commercialize products and our overall financial condition.

In general, the United States and several other jurisdictions are considering a number of legislative and regulatory 
proposals to change the healthcare system in ways that could affect our ability to sell our products profitably. 
Among policy makers and payors in the United States and elsewhere, there is significant interest in promoting 
changes in healthcare systems with the stated goals of containing healthcare costs, improving quality and/or 
expanding access to healthcare. In the United States, the pharmaceutical industry has been a particular focus of these 
efforts and has been significantly affected by major legislative initiatives. We expect to experience pricing pressures 
in connection with the sale of any products that we develop or that are being commercialized under our 
collaboration with AbbVie. The implementation of cost containment measures or other healthcare reforms may limit 
our ability to generate revenue, maintain profitability or commercialize our product candidates. 

Foreign governments tend to impose strict price controls, which may adversely affect our future profitability. 

In most foreign countries, particularly in the European Union and Japan, prescription drug pricing and/or 
reimbursement is subject to governmental control. In those countries that impose price controls, pricing negotiations 
with governmental authorities can take considerable time after the receipt of marketing approval for a product. To 
obtain reimbursement or pricing approval in some countries, we may be required to conduct a clinical trial that 
compares the cost-effectiveness of our product candidate to other available therapies. 

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Some countries require approval of the sale price of a drug before it can be marketed. In many countries, the pricing 
review period begins after marketing or product licensing approval is granted. In some foreign markets, prescription 
pharmaceutical pricing remains subject to continuing governmental control even after initial approval is granted. As 
a result, we (or AbbVie in the case of MAVYRET/MAVIRET) might obtain marketing approval for a product in a 
particular country, but then be subject to price regulations that delay commercial launch of the product, possibly for 
lengthy time periods, and negatively impact the revenues that are generated from the sale of the product in that 
country. If reimbursement of MAVYRET/MAVIRET or of any of our product candidates is unavailable or limited 
in scope or amount, or if pricing is set at unsatisfactory levels, or if there is competition from lower priced cross-
border sales, our results of operations will be negatively affected. 

If, in the future, we are unable to establish our own sales, marketing and distribution capabilities or enter into 
licensing or collaboration agreements for these purposes, we may not be successful in commercializing any 
product candidates.

We do not have a sales or marketing infrastructure and have no sales, marketing or distribution experience. We will 
seek to either build our own commercial infrastructure to commercialize any products if and when they are 
approved, or enter into licensing or collaboration agreements where our collaborator is responsible for 
commercialization, as in the case of our collaboration with AbbVie, or where we have the right to assist in the future 
development and commercialization of such products.

To develop internal sales, distribution and marketing capabilities, we will have to invest significant amounts of 
financial and management resources, some of which will be committed prior to any confirmation that any of our 
proprietary product candidates will be approved. For product candidates for which we decide to perform sales, 
marketing and distribution functions ourselves, we could face a number of additional risks, including:

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our inability to recruit and retain adequate numbers of effective sales and marketing personnel; 

the inability of sales personnel to obtain access to physicians or persuade adequate numbers of 
physicians to prescribe any products; 

the lack of complementary products to be offered by sales personnel, which may put us at a competitive 
disadvantage relative to companies with more extensive product lines; and

unforeseen costs and expenses associated with creating an independent sales and marketing 
organization.

Where and when appropriate, we may elect to utilize contract sales forces or distribution partners to assist in the 
commercialization of our product candidates. If we enter into arrangements with third parties to perform sales, 
marketing and distribution services for our products, the resulting revenues or the profitability from these revenues 
to us are likely to be lower than if we had sold, marketed and distributed our products ourselves. In addition, we may 
not be successful in entering into arrangements with third parties to sell, market and distribute our product 
candidates or may be unable to do so on terms that are favorable to us. We likely will have little control over such 
third parties, and any of these third parties may fail to devote the necessary resources and attention to sell, market 
and distribute our products effectively.

If we do not establish sales, marketing and distribution capabilities successfully, either on our own or in 
collaboration with third parties, we will not be successful in commercializing our product candidates.

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Commercial success of our product candidates depends upon significant market acceptance among physicians, 
patients and healthcare payors of any resulting approved drug. 

MAVYRET/MAVIRET, as well as EDP-305, EDP-938, EDP-514 or any other product candidate that we may 
develop in the future, whether as part of a combination therapy or as a monotherapy, may not gain market 
acceptance among physicians, healthcare payors, patients and the medical community. The degree of market 
acceptance of MAVYRET/MAVIRET or of any product candidate for which we obtain approval for commercial 
sale, will depend on a number of factors, including: 

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the efficacy and safety of treatment regimens containing one of our product candidates, as demonstrated 
in clinical trials, and the degree to which these regimens represent a clinically meaningful improvement 
in care as compared with other available therapies; 

the clinical indications for which any treatment regimen containing one of our product candidates 
become approved; 

acceptance among physicians, major operators of clinics, payors and patients of any treatment regimen 
containing one of our product candidates; 

the willingness of the target patient population to try new therapies and of physicians to prescribe these 
therapies; 

the potential and perceived advantages of treatment regimens containing one of our product candidates 
over alternative treatments; 

the cost of treatment of regimens containing one of our product candidates in relation to the cost of 
alternative treatments; 

the availability of adequate reimbursement and pricing by third parties and government authorities and 
successful negotiation of favorable agreements with payors by us or any collaborator of ours, as well as 
the impact of any agreements among any of the foregoing and one or more of our competitors limiting 
access to our product in favor of one or more competitive products; 

the continued longevity of the HCV drug market or growth and longevity of any other market for which 
we develop a drug; 

the levels of funding provided by government-funded healthcare for HCV treatment or treatment of any 
other disease for which we develop a drug;

the relative convenience and ease of administration of any treatment regimen containing one of our 
product candidates compared to competitive regimens; 

the prevalence and severity of adverse side effects, whether involving the use of treatment regimens 
containing one of our products candidates or similar, competitive treatment regimens; and

the effectiveness of our sales and marketing efforts and those of AbbVie in the case of 
MAVYRET/MAVIRET. 

If treatment regimens containing one of our product candidates are approved and then fail to achieve market 
acceptance, we may not be able to generate significant additional revenue. Further, if new, more favorably received 
therapies are introduced after any such regimen achieves market acceptance, then we may not be able to maintain 
that market acceptance over time. 

40

Risks Related to Our Dependence on Third Parties 

We may not be successful in establishing new product collaborations, which could adversely affect our ability to 
develop and commercialize one or more of our product candidates. If we are unsuccessful in maintaining or 
forming alliances on favorable terms, our business may not succeed. 

We may seek to enter into additional product collaborations in the future, including alliances with other 
biotechnology or pharmaceutical companies, to enhance and accelerate the development and commercialization of 
one or more of our product candidates. We face significant competition in seeking appropriate collaborators and the 
negotiation process is time-consuming and complex. Moreover, we may not be successful in our efforts to establish 
other product collaborations or other alternative arrangements for any product candidates and programs because our 
research and development pipeline may be insufficient, our product candidates and programs may be deemed to be 
at too early of a stage of development for collaborative effort and/or third parties may not view our product 
candidates and programs as having the requisite potential to demonstrate safety and efficacy. Even if we are 
successful in our efforts to establish product collaborations, the terms that we agree upon may not be favorable to us 
and we may not be able to maintain such product collaborations if, for example, development or approval of a 
product candidate is delayed or sales of an approved product are disappointing. 

If our existing collaboration agreement with AbbVie is terminated, or if we determine that entering into other 
product collaborations is in our best interest but we either fail to enter into, delay in entering into or fail to maintain 
such collaborations: 

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

the development of certain of our product candidates may be terminated or delayed; 

our cash expenditures related to development of certain of our product candidates would increase 
significantly and we may need to seek additional financing; 

we may be required to hire additional employees or otherwise develop expertise, such as clinical, 
regulatory, sales and marketing expertise, which we do not currently have; 

we will bear all of the risk related to the development of any such product candidates; and 

the competitiveness of any product candidate that is commercialized could be reduced. 

We intend to rely on third-party manufacturers to produce our development-stage product candidate supplies and 
any commercial supplies of any approved product candidates. Any failure by a third-party manufacturer to 
produce acceptable supplies for us may delay or impair our ability to initiate or complete our clinical trials or sell 
any resulting product. 

We do not currently own or operate any manufacturing facilities. We plan to continue to work with third-party 
contract manufacturers to produce sufficient quantities of any product candidates for preclinical testing, clinical 
trials and commercialization. If we are unable to arrange for such a third-party manufacturing source for any of our 
product candidates, or fail to do so on commercially reasonable terms, we may not be able to successfully produce, 
develop and market one or more of our product candidates, or we may be delayed in doing so. 

Reliance on third-party manufacturers entails risks to which we would not be subject if we manufactured product 
candidates ourselves, including reliance on the third party for regulatory compliance and quality control and 
assurance, volume production, the possibility of breach of the manufacturing agreement by the third party because 
of factors beyond our control (including a failure to synthesize and manufacture our product candidates in 
accordance with our product specifications) and the possibility of termination or nonrenewal of the agreement by the 
third party at a time that is costly or damaging to us. In addition, the FDA and other regulatory authorities require 
that our product candidates be manufactured according to cGMP and similar foreign standards. Pharmaceutical 
manufacturers and their subcontractors are required to register their facilities and/or products manufactured at the 
time of submission of the marketing application and then annually thereafter with the FDA and certain state and 
foreign agencies. They are also subject to periodic unannounced inspections by the FDA, state and other foreign 
authorities. Any subsequent discovery of problems with a product, or a manufacturing or laboratory facility used by 
us or our collaborators, may result in restrictions on the product or on the manufacturing or laboratory facility, 
including marketed product recall, suspension of manufacturing, product seizure, or a voluntary withdrawal of the 
drug from the market. Any failure by our third-party manufacturers to comply with cGMP or failure to scale up 
manufacturing processes, including any failure to deliver sufficient quantities of product candidates in a timely 
manner, could lead to a delay in, or failure to obtain, regulatory approval of any of our product candidates. 

41

We plan to rely on third-party manufacturers to purchase from third-party suppliers the materials necessary to 
produce our product candidates for our clinical studies. There are a small number of suppliers for certain capital 
equipment and materials that we plan to use to manufacture our drugs. Such suppliers may not sell these materials to 
our manufacturers at the times we need them or on commercially reasonable terms. Moreover, we currently do not 
have any agreements for the production of these materials. Although we do not intend to begin a clinical trial unless 
we believe we have a sufficient supply of a product candidate to complete the clinical trial, any significant delay in 
the supply of a product candidate or the material components thereof for an ongoing clinical trial due to the need to 
replace a third-party manufacturer could considerably delay completion of our clinical studies, product testing and 
potential regulatory approval of our product candidates. If our manufacturers or we are unable to purchase these 
materials after regulatory approval has been obtained for our product candidates, the commercial launch of our 
product candidates would be delayed or there would be a shortage in supply, which would impair our ability to 
generate revenue from the sale of our product candidates. 

Contract manufacturers may not be able to manufacture our product candidates at a cost or in quantities or in a 
timely manner necessary to develop and commercialize them. If we successfully commercialize any of our product 
candidates, to meet our projected needs we may need to find third parties that will increase their scale of production, 
or we may have to establish or access large-scale commercial manufacturing capabilities. We may require additional 
funds, personnel and other resources to build, lease or operate any manufacturing facility. 

A portion of our research and a portion of our manufacturing of certain key intermediates used in the 
manufacture of the active pharmaceutical ingredients for our product candidates takes place in China through 
third-party researchers and manufacturers. A significant disruption in the operation of those researchers or 
manufacturers, a trade war, or political unrest in China could materially adversely affect our business, financial 
condition and results of operations. 

Although manufacturing for MAVYRET/MAVIRET is being conducted by AbbVie, we have relied on third parties 
located in China to manufacture and supply certain key intermediates used in the manufacture of our active 
pharmaceutical ingredients, or API, for our current product candidates, and we expect to continue to use such third 
party manufacturers for such intermediates for any product candidates we develop independently. Any disruption in 
production or inability of our manufacturers in China to produce adequate quantities to meet our needs, whether as a 
result of a natural disaster or other causes, could impair our ability to operate our business on a day-to-day basis and 
to continue our research and development of our product candidates. We also use contract researchers in China to 
conduct a portion of our research for our early stage programs. Any disruption in the team conducting that research 
could cause delays in one or more of our research programs and could require us to curtail one or more programs, at 
least until we could contract for that research to be done elsewhere. Furthermore, since these researchers and 
manufacturers are located in China, we are exposed to the possibility of product supply disruption and increased 
costs in the event of changes in the policies of the United States or Chinese governments, political unrest or unstable 
economic conditions in China. For example, a trade war could lead to tarrifs on the chemical intermediates we use 
that are manufactured in China. Any of these matters could materially and adversely affect our business and results 
of operations. Any recall of the manufacturing lots or similar action regarding our API used in clinical trials could 
delay the trials or detract from the integrity of the trial data and its potential use in future regulatory filings. In 
addition, manufacturing interruptions or failure to comply with regulatory requirements by any of these 
manufacturers could significantly delay clinical development of potential products and reduce third-party or clinical 
researcher interest and support of proposed trials. These interruptions or failures could also impede 
commercialization of our product candidates and impair our competitive position. Further, we may be exposed to 
fluctuations in the value of the local currency in China. Future appreciation of the local currency could increase our 
costs. In addition, our labor costs could continue to rise as wage rates increase due to increased demand for skilled 
laborers and the availability of skilled labor declines in China. 

42

We will rely on third parties to monitor, support, conduct and/or oversee clinical trials of our product candidates 
that we develop independently and, in some cases, to maintain regulatory files for those product candidates. If we 
are not able to maintain or secure agreements with such third parties on acceptable terms, if these third parties 
do not perform their services as required, or if these third parties fail to timely transfer any regulatory 
information held by them to us, we may not be able to obtain regulatory approval for, or commercialize, our 
product candidates. 

We will rely on CROs, hospitals, clinics, academic institutions and other third-party collaborators who are outside 
our control to monitor, support, conduct and/or oversee preclinical and clinical studies of our product candidates. 
We will also rely on third parties to perform clinical trials of our product candidates when they reach that stage. As a 
result, we have less control over the timing and cost of these studies and the ability to recruit trial subjects than if we 
conducted these trials wholly by ourselves. If we are unable to maintain or enter into agreements with these third 
parties on acceptable terms, or if any such engagement is terminated, we may be unable to enroll patients on a 
timely basis or otherwise conduct our trials in the manner we anticipate. In addition, there is no guarantee that these 
third parties will devote adequate time and resources to our studies or perform as required by a contract or in 
accordance with regulatory requirements, including maintenance of clinical trial information regarding our product 
candidates. If these third parties fail to meet expected deadlines, fail to timely transfer to us any regulatory 
information, fail to adhere to protocols or fail to act in accordance with regulatory requirements or our agreements 
with them, or if they otherwise perform in a substandard manner or in a way that compromises the quality or 
accuracy of their activities or the data they obtain, then clinical trials of our product candidates may be extended, 
delayed or terminated, or our data may be rejected by the FDA or regulatory agencies. 

To the extent we elect to enter into additional licensing or collaboration agreements to partner our product 
candidates, our dependence on such relationships may adversely affect our business. 

Our commercialization strategy for some of our product candidates may depend on our ability to enter into 
collaboration agreements with other companies to obtain access to other compounds for use in combination with any 
of our product candidates or for assistance and funding for the development and potential commercialization of any 
of these product candidates, similar to what we have done with AbbVie. Supporting diligence activities conducted 
by potential collaborators and negotiating the financial and other terms of a collaboration agreement are long and 
complex processes with uncertain results. Even if we are successful in entering into one or more additional 
collaboration agreements, collaborations can involve greater uncertainty for us, as we may have limited or no 
control over certain aspects of our collaborative programs. We may determine that continuing a collaboration under 
the terms provided is not in our best interest, and we may terminate the collaboration. Our collaborators could delay 
or terminate their agreements with us, and our product candidates subject to collaborative arrangements may never 
be successfully commercialized. 

Further, our collaborators may develop alternative products or pursue alternative technologies either on their own or 
in collaboration with others, including our competitors, and the priorities or focus of our collaborators may shift 
such that our programs receive less attention or resources than we would like, or they may be terminated altogether. 
Any such actions by our collaborators may adversely affect our business prospects and ability to earn revenue. In 
addition, we could have disputes with our collaborators, such as the interpretation of terms in our agreements. Any 
such disagreements could lead to delays in the development or commercialization of any potential products or could 
result in time-consuming and expensive litigation or arbitration, which may not be resolved in our favor. 

Even with respect to programs that we intend to commercialize ourselves, we may enter into agreements with 
collaborators to share in the burden of conducting clinical trials, manufacturing and marketing our product 
candidates or products. In addition, our ability to apply our proprietary technologies to develop proprietary 
compounds will depend on our ability to establish and maintain licensing arrangements or other collaborative 
arrangements with the holders of proprietary rights to such compounds. We may not be able to establish such 
arrangements on favorable terms or at all, and our collaborative arrangements may not be successful. 

43

Risks Related to Our Intellectual Property Rights 

We could be unsuccessful in obtaining or maintaining adequate patent protection for one or more of our product 
candidates. 

Our commercial success will depend, in large part, on our ability to obtain and maintain patent and other intellectual 
property protection with respect to our product candidates. We cannot be certain that patents will be issued or 
granted with respect to our patent applications that are currently pending, or that issued or granted patents will not 
later be found to be invalid and/or unenforceable, be interpreted in a manner that does not adequately protect our 
products, or otherwise provide us with any competitive advantage. The patent position of biotechnology and 
pharmaceutical companies is generally uncertain because it involves complex legal and factual considerations. The 
standards applied by the United States Patent and Trademark Office and foreign patent offices in granting patents 
are not always applied uniformly or predictably. For example, there is no uniform worldwide policy regarding 
patentable subject matter or the scope of claims allowable in biotechnology and pharmaceutical patents. 
Consequently, patents may not issue from our pending patent applications. As such, we do not know the degree of 
future protection that we will have on our proprietary products and technology, if any, and a failure to obtain 
adequate intellectual property protection with respect to our product candidates and proprietary technology could 
have a material adverse impact on our business. 

In addition, certain of our activities have been funded, and may in the future be funded, by the United States federal 
government. For example, the preclinical and early clinical development of the lead antibiotic product candidate in 
our former antibiotic program, which we are no longer developing, was funded under a contract with NIAID, an 
entity of the United States federal government. When new technologies are developed with United States federal 
government funding, the government obtains certain rights in any resulting patents, including a nonexclusive license 
authorizing the government to use the invention for non-commercial purposes. These rights may permit the 
government to disclose our confidential information to third parties and to exercise “march-in” rights to use or allow 
third parties to use our patented technology. The government can exercise its march-in rights if it determines that 
action is necessary because we fail to achieve practical application of the United States government-funded 
technology, or because action is necessary to alleviate health or safety needs, to meet requirements of federal 
regulations or to give preference to United States industry. In addition, United States government-funded inventions 
must be reported to the government and United States government funding must be disclosed in any resulting patent 
applications. In addition, our rights in such inventions are subject to certain requirements to manufacture products in 
the United States. 

Issued patents covering one or more of our product candidates could be found invalid or unenforceable if 
challenged in court. 

Despite measures we take to obtain patent and other intellectual property protection with respect to our product 
candidates and proprietary technology, any of our intellectual property rights could be challenged or invalidated. For 
example, if we were to initiate legal proceedings against a third party to enforce a patent covering one of our product 
candidates, the defendant could counterclaim that our patent is invalid and/or unenforceable. In patent litigation in 
the United States and in some other jurisdictions, defendant counterclaims alleging invalidity and/or 
unenforceability are commonplace. Grounds for a validity challenge could be an alleged failure to meet any of 
several statutory requirements, for example, lack of novelty, obviousness or non-enablement. Grounds for an 
unenforceability assertion could be an allegation that someone connected with prosecution of the patent withheld 
relevant information from the United States Patent and Trademark Office, or the applicable foreign counterpart, or 
made a misleading statement, during prosecution. Although we believe that we have conducted our patent 
prosecution in accordance with the duty of candor and in good faith, the outcome following legal assertions of 
invalidity and unenforceability during patent litigation is unpredictable. With respect to the validity question, for 
example, we cannot be certain that there is no invalidating prior art, of which we and the patent examiner were 
unaware during prosecution. If a defendant were to prevail on a legal assertion of invalidity and/or unenforceability, 
we would lose at least part, and perhaps all, of the patent protection on a product candidate. Even if a defendant does 
not prevail on a legal assertion of invalidity and/or unenforceability, our patent claims may be construed in a manner 
that would limit our ability to enforce such claims against the defendant and others. Any loss of patent protection 
could have a material adverse impact on one or more of our product candidates and our business. 

44

Enforcing our intellectual property rights against third parties may also cause such third parties to file other 
counterclaims against us, which could be costly to defend and could require us to pay substantial damages, cease the 
sale of certain products or enter into a license agreement and pay royalties (which may not be possible on 
commercially reasonable terms or at all). Any efforts to enforce our intellectual property rights are also likely to be 
costly and may divert the efforts of our scientific and management personnel. 

Claims that our product candidates or the sale or use of our products infringe the patent or other intellectual 
property rights of third parties could result in costly litigation or could require substantial time and money to 
resolve, even if litigation is avoided. 

Our commercial success depends upon our ability to develop, manufacture, market and sell our product candidates 
and use our proprietary technology without infringing the intellectual property rights of others. We cannot guarantee 
that our product candidates or any uses of our product candidates do not and will not in the future infringe third-
party patents or other intellectual property rights. Third parties might allege that we or our collaborators are 
infringing their patent rights or that we have misappropriated their trade secrets, or that we are otherwise violating 
their intellectual property rights, whether with respect to the manner in which we have conducted our research or to 
the composition, use or manufacture of the compounds we have developed or are developing with our collaborators. 
Such third parties might resort to litigation against us or other parties we have agreed to indemnify, which litigation 
could be based on either existing intellectual property or intellectual property that arises in the future. 

It is also possible that we failed to identify, or may in the future fail to identify, relevant patents or patent 
applications held by third parties that cover our product candidates. For example, applications filed before 
November 29, 2000 and certain applications filed after that date that will not be filed outside the United States 
remain confidential until patents issue. Other patent applications in the United States and several other jurisdictions 
are published approximately 18 months after the earliest filing for which priority is claimed, with such earliest filing 
date being commonly referred to as the priority date. Furthermore, publication of discoveries in the scientific or 
patent literature often lags behind actual discoveries. Therefore, we cannot be certain that we or our collaborators 
were the first to invent, or the first to file patent applications on, our product candidates or for their uses, or that our 
product candidates will not infringe patents that are currently issued or that are issued in the future. In the event that 
a third party has also filed a patent application covering one of our product candidates or a similar invention, we 
may have to participate in an adversarial proceeding, known as an interference, declared by the U.S. Patent and 
Trademark Office or its foreign counterpart to determine priority of invention. Additionally, pending patent 
applications which have been published can, subject to certain limitations, be later amended in a manner that could 
cover our products or their use. 

In order to avoid or settle potential claims with respect to any patent or other intellectual property rights of third 
parties, we may choose or be required to seek a license from a third party and be required to pay license fees or 
royalties or both, which could be substantial. These licenses may not be available on acceptable terms, or at all. 
Even if we were able to obtain a license, the rights may be nonexclusive, which could result in our competitors 
gaining access to the same intellectual property. Ultimately, we could be prevented from commercializing a product, 
or be forced, by court order or otherwise, to cease some or all aspects of our business operations, if, as a result of 
actual or threatened patent or other intellectual property claims, we are unable to enter into licenses on acceptable 
terms. Further, we could be found liable for significant monetary damages as a result of claims of intellectual 
property infringement. For example, we have received, and may in the future receive, offers to license and demands 
to license from third parties claiming that we are infringing their intellectual property or owe license fees and, even 
if such claims are without merit, there can be no assurance that we will successfully avoid or settle such claims. 

In addition, if AbbVie licenses or otherwise acquires rights to intellectual property controlled by a third party in 
various circumstances, for example, where a product could not be legally developed or commercialized in a country 
without the third-party intellectual property right, it is entitled under our collaboration agreement to decrease 
payments payable to us on a product-by-product basis and, in certain cases, on a country-by-country basis. Any of 
the foregoing events could harm our business significantly. 

45

Defending against claims of patent infringement, misappropriation of trade secrets or other violations of intellectual 
property rights could be costly and time consuming, regardless of the outcome. Thus, even if we were to ultimately 
prevail, or to settle at an early stage, such litigation could burden us with substantial unanticipated costs. In addition, 
litigation or threatened litigation could result in significant demands on the time and attention of our management 
team, distracting them from the pursuit of other company business. Claims that our product candidates or the sale or 
use of our future products infringe, misappropriate or otherwise violate third-party intellectual property rights could 
therefore have a material adverse impact on our business. 

Unfavorable outcomes in intellectual property litigation could limit our research and development activities 
and/or our ability to commercialize certain products. 

If third parties successfully assert their intellectual property rights against us, we might be barred from using certain 
aspects of our technology, or barred from developing and commercializing certain products. Prohibitions against 
using certain technologies, or prohibitions against commercializing certain products, could be imposed by a court or 
by a settlement agreement between us and a plaintiff. In addition, if we are unsuccessful in defending against 
allegations that we have infringed, misappropriated or otherwise violated patent or other intellectual property rights 
of others, we may be forced to pay substantial damage awards to the plaintiff. There is inevitable uncertainty in any 
litigation, including intellectual property litigation. There can be no assurance that we would prevail in any 
intellectual property litigation, even if the case against us is weak or flawed. If litigation leads to an outcome 
unfavorable to us, we may be required to obtain a license from the intellectual property owner in order to continue 
our research and development programs or to market any resulting product. It is possible that the necessary license 
will not be available to us on commercially acceptable terms, or at all. Alternatively, we may be required to modify 
or redesign our products in order to avoid infringing or otherwise violating third-party intellectual property rights. 
This may not be technically or commercially feasible, may render our products less competitive, or may delay or 
prevent the entry of our products to the market. Any of the foregoing could limit our research and development 
activities, our ability to commercialize one or more product candidates, or both. 

Most of our competitors are larger than we are and have substantially greater resources. They are, therefore, likely to 
be able to sustain the costs of complex intellectual property litigation longer than we could. In addition, the 
uncertainties associated with litigation could have a material adverse effect on our ability to raise the funds 
necessary to conduct our clinical trials, continue our internal research programs, in-license needed technology, or 
enter into strategic partnerships that would help us bring our product candidates to market. 

In addition, any future intellectual property litigation, interference or other administrative proceedings will result in 
additional expense and distraction of our personnel. An adverse outcome in such litigation or proceedings may 
expose us or any future strategic partners to loss of our proprietary position, expose us to significant liabilities, or 
require us to seek licenses that may not be available on commercially acceptable terms, if at all, each of which could 
have a material adverse effect on our business. 

Intellectual property litigation may lead to unfavorable publicity that harms our reputation and causes the 
market price of our common stock to decline. 

During the course of any intellectual property litigation, there could be public announcements of the results of 
hearings, rulings on motions, and other interim proceedings in the litigation. If securities analysts or investors regard 
these announcements as negative, the perceived value of our products, programs or intellectual property could be 
diminished. Accordingly, the market price of our common stock may decline. Such announcements could also harm 
our reputation or the market for our future products, which could have a material adverse effect on our business. 

Confidentiality agreements with employees and third parties may not prevent unauthorized disclosure of trade 
secrets and other proprietary information. 

In addition to patents, we rely on trade secrets, technical know-how and proprietary information concerning our 
business strategy and product candidates in order to protect our competitive position in the field of HCV, other 
antivirals and liver disease. In the course of our research and development activities and our business activities, we 
often rely on confidentiality agreements to protect our proprietary information. Such confidentiality agreements are 
used, for example, when we talk to vendors of laboratory or clinical development services or potential strategic 

46

partners. In addition, each of our employees is required to sign a confidentiality agreement and invention assignment 
agreement upon joining our company. We take steps to protect our proprietary information, and our confidentiality 
agreements and invention assignment agreements are carefully drafted to protect our proprietary interests. 
Nevertheless, there can be no guarantee that an employee or an outside party will not make an unauthorized 
disclosure of our proprietary confidential information. This might happen intentionally or inadvertently. It is 
possible that a competitor will make use of such information, and that our competitive position will be 
compromised, in spite of any legal action we might take against persons making such unauthorized disclosures. In 
addition, to the extent that our employees, consultants or contractors use intellectual property owned by others in 
their work for us, disputes may arise as to the rights in related or resulting know-how and inventions. 

Trade secrets are difficult to protect. Although we use reasonable efforts to protect our trade secrets, our employees, 
consultants, contractors, business partners or outside scientific collaborators might intentionally or inadvertently 
disclose our trade secret information to competitors or our trade secrets may otherwise be misappropriated. 
Enforcing a claim that a third party illegally obtained and is using any of our trade secrets is expensive and time 
consuming, and the outcome is unpredictable. In addition, courts outside the United States sometimes are less 
willing than United States courts to protect trade secrets. Moreover, our competitors may independently develop 
equivalent knowledge, methods and know-how. 

Our collaborators may have rights to publish data and other information to which we have rights. In addition, 
we sometimes engage individuals or entities to conduct research relevant to our business. The ability of these 
individuals or entities to publish or otherwise publicly disclose data and other information generated during 
the course of their research is subject to certain contractual limitations. These contractual provisions may be 
insufficient or inadequate to protect our confidential information. If we do not apply for patent protection prior 
to such publication, or if we cannot otherwise maintain the confidentiality of our proprietary technology and other 
confidential information, then our ability to obtain patent protection or to protect our trade secret information may 
be jeopardized, which could adversely affect our business. 

Intellectual property rights do not necessarily protect us from all potential threats to our competitive advantage. 

The degree of future protection afforded by our intellectual property rights is uncertain because intellectual property 
rights have limitations, and may not adequately protect our business, or permit us to maintain our competitive 
advantage. The following examples are illustrative: 

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

others may be able to make compounds that are similar to our product candidates but that are not 
covered by the claims of the patents that we own or have exclusively licensed; 

we might not have been the first to make the inventions covered by the issued patents or pending patent 
applications that we own or may in the future exclusively license, which could result in the patent 
applications not issuing or being invalidated after issuing; 

we might not have been the first to file patent applications covering certain of our inventions, which 
could result in the patent applications not issuing or being invalidated after issuing; 

others may independently develop similar or alternative technologies or duplicate any of our 
technologies without infringing our intellectual property rights; 

it is possible that our pending patent applications will not lead to issued patents; 

issued patents that we own may not provide us with any competitive advantages, or may be held invalid 
or unenforceable, as a result of legal challenges by our competitors; we may obtain patents for certain 
compounds many years before we obtain marketing approval for products containing such compounds, 
and because patents have a limited life, which may begin to run prior to the commercial sale of the 
related product, the commercial value of our patents may be limited; 

our competitors might conduct research and development activities in countries where we do not have 
patent rights and then use the information learned from such activities to develop competitive products 
for sale in our major commercial markets; 

we may fail to develop additional proprietary technologies that are patentable; 

47

(cid:129)

(cid:129)

the laws of certain foreign countries may not protect our intellectual property rights to the same extent 
as the laws of the United States, or we may fail to apply for or obtain adequate intellectual property 
protection in all the jurisdictions in which we operate; and 

the patents of others may have an adverse effect on our business, for example by preventing us from 
marketing one or more of our product candidates for one or more indications. 

Any of the aforementioned threats to our competitive advantage could have a material adverse effect on our 
business. 

Changes in patent law could diminish the value of patents in general, thereby impairing our ability to protect our 
products. 

As is the case with many other biopharmaceutical companies, our success is heavily dependent on intellectual 
property, particularly patents. Obtaining, maintaining and enforcing patents in the biopharmaceutical industry 
involves both technological complexity and legal complexity. Therefore, the process of obtaining, maintaining and 
enforcing biopharmaceutical patents is costly, time-consuming and inherently uncertain. In addition, recent 
legislative and judicial developments in the United States and elsewhere have in some cases narrowed the protection 
afforded to patent owners, made patents more difficult to obtain, or increased the uncertainty regarding the ability to 
obtain, maintain and enforce patents. For example, Congress recently passed patent reform legislation, and may pass 
patent reform legislation in the future. The United States Supreme Court has ruled on several patent cases in recent 
years, and in certain circumstances has narrowed the scope of patent protection available or otherwise weakened the 
rights of patent owners. In addition to increasing uncertainty with regard to our ability to obtain patents in the future, 
this combination of events has created uncertainty with respect to the value of patents, once obtained. Depending on 
decisions and actions by the United States Congress, the federal courts, the United States Patent and Trademark 
Office, and their respective foreign counterparts, the laws and regulations governing patents could change in 
unpredictable ways that could weaken our ability to obtain new patents or to maintain and enforce our existing 
patents and patents that we might obtain in the future. 

Risks Related to Our Industry 

If product liability lawsuits are brought against us, we may incur substantial liabilities and may be required to 
limit commercialization of our product candidates. 

We face an inherent risk of product liability as a result of the clinical testing of our product candidates, and we will 
face an even greater risk if we commercialize any product candidates. For example, we may be sued if any of our 
product candidates, including any that are developed in combination therapies, allegedly causes injury or is found to 
be otherwise unsuitable during product testing, manufacturing, marketing or sale. Any such product liability claims 
may include allegations of defects in manufacturing, defects in design, a failure to warn of dangers inherent in the 
product, negligence, strict liability and a breach of warranties. Claims could also be asserted under state consumer 
protection acts. If we cannot successfully defend ourselves against product liability claims, we may incur substantial 
liabilities or be required to limit commercialization of our product candidates. Even successful defense would 
require significant financial and management resources. There is also risk that third parties we have agreed to 
indemnify could incur liability. 

Regardless of the merits or eventual outcome, liability claims may result in: 

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

decreased demand for our product candidates or any resulting products; 

injury to our reputation; 

withdrawal of clinical trial participants; 

costs to defend the related litigation; 

a diversion of management’s time and our resources; 

substantial monetary awards to trial participants or patients; 

48

(cid:129)

(cid:129)

(cid:129)

(cid:129)

product recalls, withdrawals or labeling, marketing or promotional restrictions; 

loss of revenue; 

the inability to commercialize our product candidates; and 

a decline in our stock price. 

Our inability to obtain and retain sufficient product liability insurance at an acceptable cost to protect against 
potential product liability claims could prevent or inhibit the commercialization of products we develop. We 
currently carry product liability insurance covering our clinical studies in the amount of $10.0 million in the 
aggregate. Although we maintain such insurance, any claim that may be brought against us could result in a court 
judgment or settlement in an amount that is not covered, in whole or in part, by our insurance or that is in excess of 
the limits of our insurance coverage. Our insurance policies also have various exclusions, and we may be subject to 
a product liability claim for which we have no coverage. We will have to pay any amounts awarded by a court or 
negotiated in a settlement that exceed our coverage limitations or that are not covered by our insurance, and we may 
not have, or be able to obtain, sufficient capital to pay such amounts. 

Our internal computer systems, or those of our collaborator, CROs or other contractors or consultants, may fail 
or suffer security breaches, which could result in a material disruption of development programs for our product 
candidates. 

Despite the implementation of security measures, our internal computer systems and those of our collaborators, 
CROs, and other contractors and consultants are vulnerable to damage from computer viruses, unauthorized access, 
natural disasters, terrorism, war and telecommunication and electrical failures. Information security risks have 
significantly increased in recent years in part due to the proliferation of new technologies and the increased 
sophistication and activities of organized crime, hackers, terrorists and other external parties, including foreign state 
actors. As cyber threats continue to evolve, we may be required to expend significant additional resources to 
continue to modify or enhance our protective measures or to investigate and remediate any information security 
breaches.

While we have not experienced any such system failure, accident or security breach to date, if such an event were to 
occur and cause interruptions in our operations, it could result in a material disruption of our independent drug 
development programs. For example, the loss of clinical trial data from ongoing or future clinical trials for any of 
our product candidates could result in delays in regulatory approval efforts and significantly increase costs to 
recover or reproduce the data. Our information security systems are also subject to laws and regulations requiring 
that we take measures to protect the privacy and security of certain information we gather and use in our business. 
For example, HIPAA and its implementing regulations impose, among other requirements, certain regulatory and 
contractual requirements regarding the privacy and security of personal health information. In addition to HIPAA, 
numerous other federal and state laws, including, without limitation, state security breach notification laws, state 
health information privacy laws and federal and state consumer protection laws, govern the collection, use, 
disclosure and storage of personal information. To the extent that any disruption or security breach were to result in 
a loss of or damage to data or applications, or inappropriate disclosure of confidential or proprietary information or 
personal health information, we could incur substantial liability, our reputation would be damaged, and the further 
development of our product candidates could be delayed.

49

Our relationships with customers and third-party payors in the United States and elsewhere will be subject to 
applicable anti-kickback, fraud and abuse and other healthcare laws and regulations, which could expose us to 
criminal sanctions, civil penalties, contractual damages, reputational harm and diminished profits and future 
earnings. 

Healthcare providers, physicians and third-party payors in the United States and elsewhere play a primary role in the 
recommendation and prescription of any product candidates for which we obtain marketing approval. Our future 
arrangements with third-party payors and customers may expose us to broadly applicable fraud and abuse and other 
healthcare laws and regulations that may constrain the business or financial arrangements and relationships through 
which we market, sell and distribute our products for which we obtain marketing approval. Restrictions under 
applicable federal, state and foreign healthcare laws and regulations include the following: 

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

the federal healthcare anti-kickback statute prohibits, among other things, persons from knowingly and 
willfully soliciting, offering, receiving or providing remuneration, directly or indirectly, in cash or in 
kind, to induce or reward either the referral of an individual for, or the purchase, order or 
recommendation of, any good or service for which payment may be made under federal and state 
healthcare programs such as Medicare and Medicaid; 

the federal False Claims Act imposes criminal and civil penalties, including civil whistleblower or qui 
tam actions, against individuals or entities for knowingly presenting, or causing to be presented, to the 
federal government, claims for payment that are false or fraudulent or making a false statement to avoid, 
decrease or conceal an obligation to pay money to the federal government; 

the federal Health Insurance Portability and Accountability Act of 1996, as amended by the Health 
Information Technology for Economic and Clinical Health Act, imposes criminal and civil liability for 
executing a scheme to defraud any healthcare benefit program and also imposes obligations, including 
mandatory contractual terms, with respect to safeguarding the privacy, security and transmission of 
individually identifiable health information; 

the federal false statements statute prohibits knowingly and willfully falsifying, concealing or covering 
up a material fact or making any materially false statement in connection with the delivery of or 
payment for healthcare benefits, items or services; 

the federal transparency requirements under the Patient Protection and Affordable Care Act of 2010 
requires manufacturers of drugs, devices, biologics and medical supplies to report to the Department of 
Health and Human Services information related to physician payments and other transfers of value and 
physician ownership and investment interests; 

analogous state laws and regulations, such as state anti-kickback and false claims laws, may apply to 
sales or marketing arrangements and claims involving healthcare items or services reimbursed by non-
governmental third-party payors, including private insurers, and some state laws require pharmaceutical 
companies to comply with the pharmaceutical industry’s voluntary compliance guidelines and the 
relevant compliance guidance promulgated by the federal government in addition to requiring drug 
manufacturers to report information related to payments to physicians and other healthcare providers or 
marketing expenditures; and 

analogous anti-kickback, fraud and abuse and healthcare laws and regulations in foreign countries. 

Efforts to ensure that our business arrangements with third parties will comply with applicable healthcare laws and 
regulations will involve substantial costs. It is possible that governmental authorities will conclude that our business 
practices may not comply with current or future statutes, regulations or case law involving applicable fraud and 
abuse or other healthcare laws and regulations. If our operations are found to be in violation of any of these laws or 
any other governmental regulations that may apply to us, we may be subject to significant civil, criminal and 
administrative penalties, damages, fines, exclusion from government funded healthcare programs, such as Medicare 
and Medicaid, and the curtailment or restructuring of our operations, which could have a material adverse effect on 
our business. If any of the physicians or other providers or entities with whom we expect to do business, including 
our collaborators, are found not to be in compliance with applicable laws, they may be subject to criminal, civil or 
administrative sanctions, including exclusions from government funded healthcare programs, which could also 
materially affect our business. 

50

If we fail to comply with environmental, health and safety laws and regulations, we could become subject to fines 
or penalties or incur costs that could have a material adverse effect on the success of our business. 

We are subject to numerous environmental, health and safety laws and regulations, including those governing 
laboratory procedures and the handling, use, storage, treatment and disposal of hazardous materials and wastes. Our 
operations involve the use of hazardous and flammable materials, including chemicals. Our operations also produce 
hazardous waste products. We generally contract with third parties for the disposal of these materials and wastes. 
We cannot eliminate the risk of contamination or injury from these materials. In the event of contamination or injury 
resulting from our use of hazardous materials or our or third parties’ disposal of hazardous materials, we could be 
held liable for any resulting damages, and any liability could exceed our resources. We also could incur significant 
costs associated with civil or criminal fines and penalties. 

We may incur substantial costs in order to comply with current or future environmental, health and safety laws and 
regulations. These current or future laws and regulations may impair our research, development or production 
efforts. Failure to comply with these laws and regulations also may result in substantial fines, penalties or other 
sanctions. 

We maintain workers’ compensation insurance to cover us for costs and expenses we may incur due to injuries to 
our employees resulting from the use of hazardous materials. This insurance may not provide adequate coverage 
against potential liabilities. We do not maintain insurance for environmental liability or toxic tort claims that may be 
asserted against us in connection with our storage or disposal of hazardous or radioactive materials. 

Our insurance policies are expensive and only protect us from specified business risks, which will leave us 
exposed to significant uninsured liabilities.

We do not carry insurance for all categories of risk that our business may encounter. Some of the policies we 
currently maintain include general liability, employment practices liability, property, auto, workers’ compensation, 
products liability and directors’ and officers’ insurance. We do not know, however, if we have adequate levels of 
coverage for any liability we may incur, or whether we will always be able to continue to maintain such insurance. 
Any significant uninsured liability may require us to make substantial payments, which would adversely affect our 
financial position and results of operations. Furthermore, any increase in the volatility of our stock price may result 
in us being required to pay substantially higher premiums for our directors’ and officers’ liability insurance than 
those to which we are currently subject and may even cause one or more of our underwriters to be unwilling to 
insure us.

Risks Related to Our Common Stock 

Our stock price has been, and is likely to continue to be, volatile, and thus our stockholders could incur 
substantial losses. 

Our stock price has been volatile and could be subject to wide fluctuations in response to various factors, many of 
which are beyond our control. Since our initial public offering in March 2013 and through November 1, 2018, the 
price of our common stock on the NASDAQ Global Select Market has ranged from $16.18 to $127.77. The stock 
market in general and the market for biopharmaceutical companies, and for those developing potential therapies for 
viral infections and liver diseases in particular, have experienced extreme volatility that has often been unrelated to 
the operating performance of particular companies. As a result of this volatility, you may not be able to sell your 
common stock at or above your purchase price, if at all. The market price for our common stock may be influenced 
by many factors, including: 

(cid:129)

(cid:129)

actions by AbbVie regarding HCV treatment regimens containing paritaprevir or the 
MAVYRET/MAVIRET regimen containing glecaprevir as approved in the U.S., EU and Japan, 
including announcements regarding clinical, regulatory or commercial developments or our 
collaboration; 

market expectations about and response to the levels of sales or scripts achieved by, or the announced 
prices or discounts for, AbbVie’s MAVYRET/MAVIRET regimen or competitive HCV drugs; 

51

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

failure of AbbVie’s paritaprevir-containing HCV treatment regimens to maintain their sales levels or 
AbbVie’s MAVYRET/MAVIRET regimen to achieve commercial success; 

results from or delays of clinical trials of our other product candidates, as well as results of regulatory 
reviews relating to the approval of our product candidates; 

new products, product candidates or new uses for existing products or technologies introduced or 
announced by our competitors and the timing of these introductions or announcements; 

the results of our efforts to discover or develop additional product candidates; 

our dependence on third parties, including our collaborators, CROs, manufacturers, clinical trial 
sponsors and clinical investigators; 

regulatory, political or legal developments in the United States or other countries; 

developments or disputes concerning patent applications, issued patents or other proprietary rights; 

the recruitment or departure of key scientific or management personnel; 

our ability to commercialize our product candidates we develop independently, if approved; 

the level of expenses related to any of our product candidates or clinical development programs; 

actual or anticipated changes in estimates as to financial results, development timelines or 
recommendations by securities analysts; 

period-to-period variations in our financial results or those of companies that are perceived to be similar 
to us; 

sales of common stock by us or our stockholders in the future, as well as the overall trading volume of 
our common stock; 

changes in the structure of healthcare payment systems or other actions that affect the effective 
reimbursement rates for treatment regimens containing our products or for competitive regimens; 

market conditions in the pharmaceutical and biotechnology sectors; 

general economic, industry and market conditions and other factors that may be unrelated to our 
operating performance or the operating performance of our competitors, including changes in market 
valuations of similar companies; and 

the other factors described in this “Risk Factors” section. 

Provisions in our corporate charter documents and under Delaware law could make an acquisition of us, which 
may be beneficial to our stockholders, more difficult and may prevent attempts by our stockholders to replace or 
remove our current management. 

Provisions in our corporate charter and our bylaws may discourage, delay or prevent a merger, acquisition or other 
change in control of us that stockholders may consider favorable, including transactions in which they might 
otherwise receive a premium for their shares. 

These provisions could also limit the price that investors might be willing to pay in the future for shares of our 
common stock, thereby depressing the market price of our common stock. In addition, because our board of 
directors is responsible for appointing the members of our management team, these provisions may frustrate or 
prevent any attempts by our stockholders to replace or remove our current management by making it more difficult 
for stockholders to replace members of our board of directors. Among other things, these provisions: 

(cid:129)

(cid:129)

(cid:129)

establish a classified or staggered board of directors such that not all members of the board are elected at 
one time; 

allow the authorized number of our directors to be changed only by resolution of our board of directors; 

limit the manner in which stockholders can remove directors from the board; 

52

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

establish advance notice requirements for stockholder proposals that can be acted on at stockholder 
meetings and nominations to our board of directors; 

require that stockholder actions must be effected at a duly called stockholder meeting and prohibit 
actions by our stockholders by written consent; 

limit who may call stockholder meetings; 

provide that the state courts or, in certain circumstances, the federal courts, in Delaware shall be the sole 
and exclusive forum for certain actions involving us, our directors, officers, employees and 
stockholders; 

provide our board of directors with the authority to designate the terms of and issue a new series of 
preferred stock without stockholder approval, which could be used to institute a “poison pill” that would 
work to dilute the stock ownership of a potential hostile acquirer, effectively preventing acquisitions 
that have not been approved by our board of directors; and 

require the approval of the holders of at least 66 2/3% of the votes that all our stockholders would be 
entitled to cast to amend or repeal certain provisions of our charter or bylaws. 

Moreover, because we are incorporated in Delaware, we are governed by the provisions of Section 203 of the 
Delaware General Corporation Law, which prohibit a person who owns 15% or more of our outstanding voting 
stock from merging or combining with us for a period of three years after the date of the transaction in which the 
person acquired in excess of 15% of our outstanding voting stock, unless the merger or combination is approved in a 
prescribed manner. Any provision in our corporate charter or our bylaws or Delaware law that has the effect of 
delaying or deterring a change in control could limit the opportunity for our stockholders to receive a premium for 
their shares of our common stock, and could also affect the price that some investors are willing to pay for our 
common stock. 

Our employment agreements with our executive officers may require us to pay severance benefits to any of those 
persons who are terminated in connection with a change of control of us, which could harm our financial 
condition or results. 

Our executive officers are parties to employment agreements that provide for aggregate cash payments of up to 
approximately $4.6 million for severance and other non-equity-based benefits in the event of a termination of 
employment in connection with a change of control of our company. In addition, based on the closing price of our 
common stock as of September 30, 2018 of $85.46 per common share, the aggregate intrinsic value of unvested 
stock options and other equity awards subject to accelerated vesting upon these events was $35.8 million. The 
accelerated vesting of awards options could result in dilution to our stockholders and harm the market price of our 
common stock. The payment of these severance benefits could harm our company’s financial condition and results. 
In addition, these potential severance payments may discourage or prevent third parties from seeking a business 
combination with us. 

If we fail to maintain an effective system of internal control over financial reporting, we may not be able to 
accurately report our financial results or prevent fraud. As a result, stockholders could lose confidence in our 
financial and other public reporting, which would harm our business and the trading price of our common stock.

Effective internal controls over financial reporting are necessary for us to provide reliable financial reports and, 
together with adequate disclosure controls and procedures, are designed to prevent fraud. Any failure to implement 
newly required or improved controls, or difficulties encountered in their implementation, could cause us to fail to 
meet our reporting obligations. In addition, any testing by us conducted in connection with Section 404 of the 
Sarbanes-Oxley Act of 2002, or any subsequent testing by our independent registered public accounting firm, may 
reveal deficiencies in our internal controls over financial reporting that are deemed to be material weaknesses or that 
may require prospective or retroactive changes to our financial statements or identify other areas for further attention 
or improvement. Inferior internal controls could also cause investors to lose confidence in our reported financial 
information, which could have a negative effect on the trading price of our common stock.

53

Because we do not anticipate paying cash dividends on our common stock for the foreseeable future, investors in 
our common stock may never receive a return on their investment. 

You should not rely on an investment in our common stock to provide dividend income. We do not anticipate that 
we will pay any cash dividends to holders of our common stock for the foreseeable future. Instead, we plan to retain 
any earnings to maintain and expand our existing operations. 

Accordingly, investors must rely on sales of their common stock after price appreciation, which may never occur, as 
the only way to realize any return on their investment. As a result, investors seeking cash dividends should not 
invest in our common stock. 

A sale of a substantial number of shares of our common stock in the public market could cause the market price 
of our common stock to drop significantly, even if our business is doing well. 

Sales of a substantial number of shares of our common stock in the public market could occur at any time. These 
sales, or the perception in the market that the holders of a large number of shares intend to sell shares, could reduce 
the market price of our common stock. As of September 30, 2018, we had 19.4 million shares of common stock 
outstanding. In addition, as of September 30, 2018, 2.6 million and 0.2 million shares of common stock that are 
subject to outstanding options or restricted stock unit awards, respectively, under our outstanding equity plans are 
eligible for sale in the public market to the extent permitted by the provisions of various vesting schedules, and 
Rules 144 and 701 under the Securities Act. If these additional shares of common stock are sold, or it is perceived 
that they will be sold, in the public market, the trading price of our common stock could decline. 

If securities or industry analysts do not publish research, or publish inaccurate or unfavorable research about 
our business, our stock price and trading volume could decline. 

The trading market for our common stock will depend in part on the research and reports that securities or industry 
analysts publish about us or our business. If those analysts are unable to predict accurately the demand and net sales 
of AbbVie’s HCV regimens, that could result in our reported revenues and earnings being lower than the so-called 
“market consensus” of our projected revenues, which could negatively affect our stock price. In addition, if too few 
securities or industry analysts cover our company, the trading price for our stock would likely be negatively 
impacted. In the event that one or more of the analysts who cover us downgrade our stock or publish inaccurate or 
unfavorable research about our business, our stock price would likely decline. If one or more of these analysts cease 
coverage of our company or fail to publish reports on us regularly, demand for our stock could decrease, which 
might cause our stock price and trading volume to decline.

ITEM 1B. UNRESOLVED STAFF COMMENTS 

None. 

ITEM  2.

PROPERTIES 

Our corporate headquarters is located in Watertown, Massachusetts, where we lease approximately 49,000 square 
feet of office and laboratory space. The term of our current lease expires on September 1, 2022. We also lease 
additional office space located in Watertown, Massachusetts of approximately 18,000 square feet. The term of this 
lease expires August 1, 2024. 

ITEM  3.

LEGAL PROCEEDINGS 

We are not a party to any material legal proceedings. 

ITEM 4. MINE SAFETY DISCLOSURES 

Not applicable. 

54

PART II 

ITEM 5. MARKET FOR THE COMPANY’S COMMON EQUITY, RELATED STOCKHOLDER 

MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES 

Market and Stockholder Information 

Our common stock has been listed on The NASDAQ Global Select Market under the symbol “ENTA” since 
March 21, 2013. The following table shows the high and low sales price for our common stock as reported by The 
NASDAQ Global Select Market for the quarterly periods in the fiscal years ended September 30, 2018 and 2017:

First Quarter

Second Quarter

Third Quarter

Fourth Quarter

First Quarter

Second Quarter

Third Quarter

Fourth Quarter

Fiscal 2018

High

Low

59.88   $

95.91   $

122.43   $
127.77   $

44.52 

52.39 

78.89 

81.24  

Fiscal 2017

High

Low

34.53   $

36.05   $

37.54   $
46.80   $

22.32 

27.72 

29.45 

33.42  

  $
  $
  $
  $

  $
  $
  $
  $

As of November 1, 2018 there were 22 stockholders of record of our common stock, which excludes stockholders 
whose shares were held in nominee or street name by brokers.

We have never declared or paid cash dividends on our common stock, and we do not expect to declare or pay any 
cash dividends for the foreseeable future. 

Performance Graph(1) 

The following graph shows a comparison from September 30, 2013 through September 30, 2018 of cumulative total 
return on assumed investments of $100.00 in cash in each of our common stock, the NASDAQ Composite Index 
and the NASDAQ Biotechnology Index. Such returns are based on historical results and are not intended to suggest 
future performance. Data for the NASDAQ Composite Index and the NASDAQ Biotechnology Index assume 
reinvestment of dividends. 

55

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
COMPARISON OF FIVE YEARS CUMULATIVE TOTAL RETURN 
Among Enanta Pharmaceuticals, Inc., the NASDAQ Composite Index, 
and the NASDAQ Biotechnology Index 

(1)

This performance graph shall not be deemed to be “soliciting material” or to be “filed” with the SEC for 
purposes of Section 18 of the Securities and Exchange Act of 1934, as amended, or otherwise subject to the 
liabilities under that Section, and shall not be deemed incorporated by reference into any filing of Enanta 
Pharmaceuticals, Inc. under the Securities Act of 1933, as amended. 

56

 
 
ITEM 6.

SELECTED CONSOLIDATED FINANCIAL DATA 

We have derived the consolidated statements of operations data for the years ended September 30, 2018, 2017, and 
2016 and the consolidated balance sheet data as of September 30, 2018 and 2017 from our audited financial 
statements included elsewhere in this Annual Report on Form 10-K. The selected statements of operations data for 
the years ended September 30, 2015 and 2014 and the balance sheet data as of September 30, 2016, 2015 and 2014 
are derived from our audited financial statements not included in this Annual Report on Form 10-K. Our historical 
results for any prior period are not necessarily indicative of any results to be expected for any future period. 

Consolidated Statements of Operations Data:

Revenue
Operating expenses:

Research and development
General and administrative

Total operating expenses

Income from operations
Other income (expense), net

Net income before income taxes
Income tax (expense) benefit

Net income

Net income per share:

Basic
Diluted

Weighted average common shares outstanding:

Basic
Diluted

Consolidated Balance Sheet Data:

Cash, cash equivalents and marketable securities

Working capital

Total assets

Capital lease obligation

Warrant liability

Series 1 nonconvertible preferred stock

Total stockholders’ equity

2018

Years Ended September 30,
2017
2015
2016
(in thousands, except per share data)

2014

 $ 206,625   $ 102,814 

 $ 88,268 

 $ 160,880 

 $ 47,741 

94,856    
23,441    
   118,297    

57,451 
20,749 
78,200 

40,461 
16,966 
57,427 

23,189 
13,543 
36,732 

88,328    
4,793    

24,614 
2,333 

30,841 
1,719 

   124,148 
1,307 

18,740 
10,016 
28,756 

18,985 
283 

93,121    
(21,165)   

26,947 
(9,237)
 $ 71,956   $ 17,710 

32,560 
(10,894)
 $ 21,666 

   125,455 
(46,463)
 $ 78,992 

19,268 
15,170 
 $ 34,438 

 $
 $

3.74   $
3.48   $

0.93 
0.91 

 $
 $

1.14 
1.13 

 $
 $

4.23 
4.09 

 $
 $

1.88 
1.80 

19,255    
20,650    

19,066 
19,407 

18,929 
19,224 

18,673 
19,295 

18,355 
19,185  

2018

2017

As of September 30,
2016
(in thousands)

2015

2014

 $ 325,119 
   364,364 
   414,227 
379 

— 

1,628 
   393,679 

 $ 293,707 

 $ 242,203 

 $ 209,443 

 $ 131,767 

   216,837 

   224,267 

   163,937 

   103,229 

   326,637 

   281,277 

   246,013 

   155,415 

458 

807 

762 

531 

1,251 

159 

598 

1,276 

163 

— 

1,584 

202 

   301,676 

   269,936 

   236,157 

   148,654  

57

 
 
 
 
 
   
 
 
 
 
 
 
 
 
 
 
  
     
 
 
  
 
 
  
 
 
  
 
 
  
     
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
  
  
  
  
  
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
  
  
  
  
  
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
     
  
  
  
  
  
  
  
  
     
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
    
       
       
       
       
 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
ITEM 7.
RESULTS OF OPERATIONS 

MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND 

You should read the following discussion and analysis of financial condition and results of operations together with 
the section entitled “Selected Consolidated Financial Data” and our consolidated financial statements and related 
notes included elsewhere in this Annual Report on Form 10-K. This discussion and other parts of this Annual Report 
on Form 10-K contain forward-looking statements that involve risks and uncertainties, such as statements regarding 
our plans, objectives, expectations, intentions and projections. Our actual results could differ materially from those 
discussed in these forward-looking statements. Factors that could cause or contribute to such differences include, 
but are not limited to, those discussed in the “Risk Factors” section of this Annual Report on Form 10-K. 

Overview 

We are a biotechnology company that uses our robust, chemistry-driven approach and drug discovery capabilities to 
create small molecule drugs primarily for the treatment of viral infections and liver diseases. We discovered 
glecaprevir, the second of two protease inhibitors discovered and developed through our collaboration with AbbVie 
for the treatment of chronic hepatitis C virus, or HCV. Glecaprevir is co-formulated as part of AbbVie’s newest 
direct-acting antiviral (DAA) combination and marketed under the tradenames MAVYRET™ (U.S.) or 
MAVIRET™ (ex-U.S.) (glecaprevir/pibrentasvir). Our royalties from our AbbVie collaboration and our existing 
financial resources provide us funding to support our wholly-owned research and development programs, which are 
currently focused on the following disease targets: 

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respiratory syncytial virus, or RSV, the most common cause of bronchiolitis and pneumonia in children 
under one year of age in the U.S., resulting in an estimated 57,000 to 125,000 hospitalizations each year 
in the U.S.; 

non-alcoholic steatohepatitis, or NASH, a liver disease estimated to affect approximately 1.5% to 6.5% 
of the population in the developed world (which is the equivalent of approximately 5 to 20 million 
individuals in the U.S. alone);

primary biliary cholangitis, or PBC, a chronic liver disease that slowly destroys bile ducts in the liver, 
which affects an estimated 17,000 individuals in the U.S.; and

hepatitis B virus, or HBV, the most prevalent chronic hepatitis, which is estimated to affect 
approximately 250 million individuals worldwide.

We had $325.1 million in cash, cash equivalents and marketable securities at September 30, 2018. In fiscal 2018, we 
earned $191.6 million in per-product royalties on AbbVie’s net sales of its HCV regimens and we earned the 
remaining $15.0 million milestone payment from AbbVie upon reimbursement approval for MAVIRET™ in Japan. 
We expect our existing financial resources and future royalties from our AbbVie collaboration will allow us to 
continue to fund our wholly-owned research and development programs for the foreseeable future.

Our Wholly-Owned Programs 

Our wholly-owned research and development programs are in virology, namely RSV and HBV, and in liver disease 
(non-virology), namely NASH and PBC: 

(cid:129)

RSV: We discovered EDP-938, a potent N-protein inhibitor of activity of both major subgroups of RSV, 
referred to as RSV-A and RSV-B, and have tested it as our first clinical candidate for RSV. We believe 
EDP-938 is differentiated from fusion inhibitors currently in development for RSV because N-protein 
inhibitors directly target the viral replication process of RSV and have demonstrated high barriers to 
resistance against RSV in vitro. 

o

In our fiscal 2018, we completed a Phase 1 clinical study demonstrating that EDP-938 was 
generally safe and well tolerated over a broad range of single and multiple doses with good 
pharmacokinetic data.

58

(cid:129)

(cid:129)

o We initiated a Phase 2a challenge study of EDP-938 in October 2018. The challenge study will 
test the effect of EDP-938 on healthy volunteers who will be infected with RSV and then treated 
with EDP-938 or placebo during the course of the study. Primary and secondary outcome 
measures include changes in viral load measurements and change of baseline symptoms.

o

Preclinical data demonstrated that EDP-938 is a potent inhibitor of both RSV-A and RSV-B 
activity, maintaining antiviral activity post-infection while presenting a high barrier to 
resistance in vitro.

NASH and PBC: We are working on multiple compounds that selectively bind to and activate the 
farnesoid X receptor, or FXR. We plan to develop these compounds, referred to as FXR agonists, for 
use in the treatment of NASH and PBC, both of which are liver diseases with very few therapeutic 
options. Our lead FXR agonist, EDP-305, represents a new class of FXR agonist designed to take 
advantage of increased binding interactions with the receptor. We believe this class is significantly 
different from other FXR agonists in clinical development.

o

In October 2017, we announced results of a Phase 1a/b clinical study of EDP-305, which was 
generally safe and well tolerated over a broad range of single and multiple doses with 
pharmacokinetic data supporting once daily oral dosing. Additional data from this study were also 
presented at the 2018 NASH-TAG conference and the International Liver CongressTM (ILC) 2018. 
The study included 98 healthy volunteer subjects, or HV subjects, and 48 subjects who were 
obese and with or without pre-diabetes or type 2 diabetes, whom we refer to as subjects with 
presumptive non-alcoholic fatty liver disease, or PN subjects.

o We have presented data at the 2017 and 2018 annual meetings of the American Association for 

the Study of Liver Diseases (AASLD), the 2017 and 2018 NASH-TAG conferences and the 2017 
and 2018 ILC conferences that demonstrated that EDP-305 is a highly selective FXR agonist and 
shows more potent activity in a variety of in vitro and in vivo NASH models compared to the most 
advanced NASH candidate in development today, obeticholic acid, or OCA.

o We initiated a Phase 2 clinical study, known as ARGON-1, of EDP-305 in NASH patients and a 

Phase 2 clinical study, known as INTREPID, of EDP-305 in PBC patients. 

o

o

EDP-305 has been granted Fast Track designation by the U.S. Food and Drug Administration 
(FDA) for the treatment of NASH patients with liver fibrosis and separately for the treatment of 
PBC.

In addition, we are pursuing research in other classes of FXR agonists as well as other 
mechanisms that may provide therapeutic benefit in NASH, any of which could be used in 
combination therapies for NASH.

HBV: We also have a program to discover and develop new chemical entities for the treatment of HBV. 
Our initial focus is on core inhibitors, a mechanism with early clinical validation. In November 2018, 
we announced our first clinical candidate for HBV. EDP-514 is an HBV core inhibitor, also known as a 
core protein allosteric modulator, or CpAM, or capsid assembly modulator. 

o

o

EDP-514 was selected from our lead class of HBV compounds that are characterized by potent 
antiviral activity. In vitro, they are capable of preventing the establishment of cccDNA, are pan-
genotypic, are active against known nucleos(t)ide resistant mutants, and are additive to synergistic 
with nucleoside analogs and other core inhibitors. Members of this class have also demonstrated 
excellent reduction in HBV titers in a chimeric mouse model with human liver cells.

In addition, we are also seeking patent protection and conducting preclinical experiments with 
compounds we have discovered that use other mechanisms to target HBV. We believe that it may 
be necessary to utilize more than one compound/mechanism for the treatment of HBV and 
therefore we are pursuing multiple approaches. 

59

We have utilized our internal chemistry and drug discovery capabilities to generate all of our development-stage 
programs.

Our Out-Licensed Products 

Through our Collaborative Development and License Agreement with AbbVie, we have developed and out-licensed 
to AbbVie two protease inhibitor compounds that have been clinically tested, manufactured, and commercialized by 
AbbVie. To date, we have earned all $330.0 million milestone payments under the agreement related to clinical 
development and commercialization regulatory approvals of these regimens in major markets.

(cid:129)

(cid:129)

Glecaprevir: Glecaprevir is the protease inhibitor we discovered that was developed by AbbVie in a 
fixed-dose combination with its NS5A inhibitor, pibrentasvir, for the treatment of HCV. This 
combination, currently marketed under the brand name MAVYRET™ (U.S.) and MAVIRET™ (ex-
U.S.) and referred to in this report as MAVYRET/MAVIRET, is a novel, once daily, all oral, fixed-
dose, ribavirin-free treatment for HCV genotypes 1-6, or GT1-6, which is referred to as being pan-
genotypic. In the U.S., EU and Japan it was approved as an 8-week treatment for patients without 
cirrhosis and new to treatment. Today, these patients are estimated to represent the majority of HCV 
patients in developed country markets.

Since August 2017, substantially all of our royalty revenue has been derived from AbbVie’s net sales of 
MAVYRET/MAVIRET. Our ongoing royalty revenues from this regimen consist of annually tiered, 
double-digit, per-product royalties (see Note 7 in Notes to Consolidated Financial Statements) on 50% 
of the calendar year net sales of the 2-DAA glecaprevir/pibrentasvir combination in 
MAVYRET/MAVIRET. These royalties are calculated separately from the royalties on other 
paritaprevir-containing regimens.

Paritaprevir: Paritaprevir is the protease inhibitor contained in AbbVie’s initial HCV treatment regimens 
sold under the tradenames VIEKIRAX® (ex-U.S.) and VIEKIRA PAK® (U.S.) 
(paritaprevir/ritonavir/ombitasvir/dasabuvir). These regimens are no longer being actively marketed in 
markets where MAVYRET/MAVIRET is approved and reimbursed. AbbVie’s paritaprevir-containing 
regimens were first approved and sold in the U.S. in December 2014. Through our 2017 fiscal year end, 
our royalty revenues were generated substantially through worldwide net sales of these regimens. 

Financial Operations Overview 

We are currently funding all research and development for our wholly-owned programs, which are targeted towards 
the discovery and development of novel compounds for the treatment of viral infections and liver diseases. In fiscal 
2018, we initiated two Phase 2 studies of EDP-305, one in PBC patients, known as the INTREPID study, and one in 
NASH patients, known as the ARGON-1 study. We also initiated a Phase 2a clinical study of our lead RSV 
candidate, EDP-938, in October 2018. In November 2018 we announced our selection of EDP-514 as our first 
candidate for HBV. As a result of these efforts as well as efforts to advance other compounds into substantial 
preclinical development, we increased our research and development expenses in fiscal year 2018, as compared to 
our fiscal year 2017. We expect to incur substantially greater expenses in fiscal 2019 as we continue to advance our 
FXR agonist program as well as our RSV and HBV programs.

We are funding our operations primarily through payments received under our collaboration agreement with 
AbbVie. Our revenue from our collaboration agreement has resulted in our reporting net income in each of our past 
seven fiscal years. Our revenue is dependent on royalty payments we receive from AbbVie on its sales of 
MAVYRET/MAVIRET. 

For its MAVYRET/MAVIRET regimen, which in the majority of chronic HCV patients only requires 8 weeks of 
treatment compared to 12 weeks with VIEKIRA PAK® and other HCV regimens, AbbVie initially set a lower list 
price compared to its original HCV regimens and other HCV products on the market. In 2018, AbbVie has reported 
increasing MAVYRET/MAVIRET market share and has become the leading HCV treatment in the U.S. and several 
market geographies in developed countries where it is approved. However, the market for HCV therapies remains 
very dynamic in several jurisdictions where MAVYRET/MAVIRET is already approved or AbbVie is seeking 
approval, and we cannot predict how that market will continue to evolve. 

60

Given the uncertainty regarding the level of AbbVie’s future MAVYRET/MAVIRET sales that will generate our 
royalty revenue and the development risks affecting the extent and timing of our future expenditures for the 
advancement of our internally developed compounds, it is uncertain whether we will continue to report net income 
in fiscal 2019 and thereafter. 

Revenue 

Our revenue is derived from our collaboration agreement with AbbVie. In our fiscal year ended September 30, 2016, 
we generated royalty revenue from AbbVie’s net sales allocable to paritaprevir, which was part of AbbVie’s initial 
treatment regimens for HCV approved in the U.S. in December 2014 and in the EU and dozens of other countries 
subsequently. Since then, AbbVie received approvals of its newest HCV regimen, MAVYRET/MAVIRET, in the 
U.S. and EU in the summer of 2017. Substantially all our royalty revenues are now derived from the 
MAVYRET/MAVIRET as this regimen generally has a shorter treatment duration (8-week treatment as approved in 
the EU, U.S. and Japan versus 12 weeks for paritaprevir and competitive regimens) and is pan-genotypic.

The following table is a summary of revenue recognized for the years ended September 30, 2018, 2017, and 2016:

AbbVie agreement:
Milestones
Royalties
NIAID contract:
Total revenue

AbbVie Agreement 

Years Ended September 30,

2018

2017
(in thousands)

2016

 $

 $

15,000 
191,625 
— 
206,625 

 $

 $

65,000 
37,814 
— 
102,814 

 $

 $

30,000 
57,692 
576 
88,268  

Since all of our research obligations under the AbbVie agreement were concluded by June 30, 2011, all milestone 
payments received since then have been recognized as revenue upon achievement of each milestone by AbbVie. 
During the fiscal year ended September 30, 2018, we earned and recognized as revenue the last milestone payment 
for glecaprevir, which was a $15.0 million milestone payment upon AbbVie’s achievement of commercialization 
regulatory approval of MAVIRET™ in Japan. During the fiscal year ended September 30, 2017, we earned and 
recognized as revenue a total of $65.0 million in milestone payments upon approval of the MAVYRET/MAVIRET 
regimen in the U.S. and EU. During the fiscal year ended September 30, 2016, we earned and recognized the last 
milestone payment for paritaprevir, a $30.0 million milestone payment, upon AbbVie’s achievement of 
commercialization regulatory approval of its paritaprevir-containing regimen in Japan. 

We currently receive annually tiered, double-digit royalties per protease inhibitor product on AbbVie’s net sales 
allocable to either of our collaboration’s protease inhibitor products. Under the terms of our AbbVie agreement, as 
amended in October 2014, 50% of AbbVie’s net sales of MAVYRET/MAVIRET are allocated to glecaprevir. In the 
case of regimens containing paritaprevir, 30% of net sales of 3-DAA regimens containing paritaprevir and 45% of 
net sales of 2-DAA regimens containing paritaprevir are allocated to paritaprevir for purposes of calculating our 
annually tiered royalties. Beginning with each January 1, the cumulative net sales of each royalty-bearing product 
start at zero for purposes of calculating the tiered royalties on a product-by-product basis. For detail regarding the 
royalty tier, see Note 7 in Notes to Consolidated Financial Statements of this report which is incorporated herein by 
this reference.

We expect all of our revenue in 2019 to be generated from our collaboration agreement with AbbVie.

Internal Programs 

As our internal product candidates are currently in preclinical or early clinical development, we have not generated 
any revenue from our own product sales and do not expect to generate any revenue from product sales derived from 
these product candidates for at least the next several years. 

61

 
 
 
 
 
 
 
 
 
 
 
 
 
  
  
  
  
    
 
  
  
  
  
  
  
Operating Expenses 

The following table summarizes our operating expenses for the years ended September 30, 2018, 2017, and 2016: 

2018

Years Ended September 30,
2017
(in thousands)

2016

Research and development
General and administrative

Total operating expenses

 $

94,856   $
23,441    
 $ 118,297   $

57,451   $
20,749    
78,200   $

40,461 
16,966 
57,427  

Research and Development Expenses 

Research and development expenses consist of costs incurred to conduct basic research, such as the discovery and 
development of novel small molecules as therapeutics, as well as any external expenses of preclinical and clinical 
development activities. We expense all costs of research and development as incurred. These expenses consist 
primarily of: 

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

personnel costs, including salaries, related benefits and stock-based compensation for employees 
engaged in scientific research and development functions;

third-party contract costs relating to research, formulation, manufacturing, preclinical study and clinical 
trial activities;

laboratory consumables; 

allocated facility-related costs; and

third-party license fees.

Project-specific expenses reflect costs directly attributable to our clinical development candidates and preclinical 
candidates nominated and selected for further development. Remaining research and development expenses are 
reflected in research and drug discovery, which represents early-stage drug discovery programs. At any given time, 
we typically have several active early stage research and drug discovery projects. Our internal resources, employees 
and infrastructure are not directly tied to any individual research or drug discovery project and are typically 
deployed across multiple projects. As such, we do not report information regarding costs incurred for our early-stage 
research and drug discovery programs on a project-specific basis. We expect that our research and development 
expenses will continue to increase in the future as we advance our RSV, NASH, PBC, and HBV programs.

Our research and drug discovery programs are at early stages; therefore, the successful development of our product 
candidates is highly uncertain and may not result in approved products. Completion dates and completion costs can 
vary significantly for each product candidate and are difficult to predict. Given the uncertainty associated with 
clinical trial enrollments and the risks inherent in the development process, we are unable to determine the duration 
and completion costs of the current or future clinical trials of our product candidates or if, or to what extent, we will 
generate revenue from the commercialization and sale of any of our product candidates. We anticipate that we will 
make determinations as to which development programs to pursue and how much funding to direct to each program 
on an ongoing basis in response to the preclinical and clinical success and prospects of each product candidate, as 
well as ongoing assessments of the commercial potential of each product candidate.

General and Administrative Expenses 

General and administrative expenses consist primarily of personnel costs, which include salaries, related benefits 
and stock-based compensation, of our executive, finance, business and corporate development and other 
administrative functions. General and administrative expenses also include travel expenses, allocated facility-related 
costs not otherwise included in research and development expenses, directors and officers liability insurance 
premiums, and professional fees for auditing, tax, and legal services and patent expenses.

We expect that general and administrative expenses will increase in the future primarily due to ongoing expansion of 
our operating activities in support of our own research and development programs, as well as potential additional 
costs associated with operating a growing publicly traded company.

62

 
 
 
 
 
 
 
 
 
 
 
 
 
  
Other Income (Expense)

Other income (expense) consists of interest income, interest expense and the change in fair value of our outstanding 
Series 1 nonconvertible preferred stock and, during the periods the Series 1 nonconvertible preferred stock warrants 
were outstanding, the change in fair value of our warrant liability. Interest income consists of interest earned on our 
cash equivalents and short-term and long-term marketable securities balances as well as interest earned for any 
refunds received from tax authorities. Interest expense consists of interest expense related to our capital lease 
obligation. The change in fair value of our Series 1 nonconvertible preferred stock (and warrant liability when the 
warrants were outstanding) relates to the remeasurement of these financial instruments from period to period as 
these instruments may require a transfer of assets because of the liquidation preference features of the underlying 
stock. The change in fair value also includes the forfeiture of unexercised warrants which expired on October 4, 
2017.

Income Tax Expense 

Income tax expense for the years ended September 30, 2018, 2017, and 2016 resulted from federal and state taxes 
attributable to our operating income. 

Critical Accounting Policies 

Our consolidated financial statements are prepared in accordance with accounting principles generally accepted in 
the United States of America. The preparation of our consolidated financial statements and related disclosures 
requires us to make estimates and assumptions that affect the reported amount of assets, liabilities, revenue, costs 
and expenses, and related disclosures. We believe that the estimates and assumptions involved in the accounting 
policies described below may have the greatest potential impact on our consolidated financial statements and, 
therefore, consider these to be our critical accounting policies. We evaluate our estimates and assumptions on an 
ongoing basis. Actual results may differ from these estimates under different assumptions and conditions. See also 
Note 2 to the consolidated financial statements included elsewhere in this Annual Report on Form 10-K for 
information about these critical accounting policies as well as a description of our other significant accounting 
policies. 

Revenue Recognition 

Our revenue has been generated primarily through collaborative research and license agreements. The terms of these 
agreements contain multiple deliverables which may include (i) licenses, (ii) research and development activities, 
and (iii) participation in joint research and development steering committees. The terms of these agreements may 
include nonrefundable upfront license fees, payments for research and development activities, payments based upon 
the achievement of certain milestones, and royalty payments based on product sales derived from the collaboration. 
The majority of revenue is derived under our agreement with AbbVie. Under this agreement, we have no ongoing 
deliverables and therefore, royalties and milestones received under this arrangement are recognized when earned. In 
all instances, revenue is recognized only when the price is fixed or determinable, persuasive evidence of an 
arrangement exists, delivery has occurred or the services have been rendered, collectibility of the resulting 
receivable is reasonably assured, and we have fulfilled our performance obligations under the contract. 

We apply Accounting Standards Codification No. 605-25, Revenue Recognition Multiple-Deliverable Revenue 
Arrangements, or ASC 605-25, for multiple element arrangements entered into or materially modified on or after 
October 1, 2011. The selling prices of deliverables under the arrangement may be derived using third-party 
evidence, (“TPE”) or a best estimate of selling price (“BESP”), if vendor-specific objective evidence (“VSOE”), is 
not available. The objective of BESP is to determine the price at which we would transact a sale if the element 
within the license agreement was sold on a standalone basis. Establishing BESP involves management’s judgment 
and considers multiple factors, including market conditions and company-specific factors such as those factors 
contemplated in negotiating the agreements as well as internally developed models that include assumptions related 
to market opportunity, discounted cash flows, estimated development costs, probability of success, and the time 
needed to commercialize a product candidate pursuant to the license. In validating our BESP, we consider whether 
changes in key assumptions used to determine the BESP will have a significant effect on the allocation of the 
arrangement consideration between the multiple deliverables. Deliverables under a multiple element arrangement 
are separated into multiple units if (i) the delivered item has value to the customer on a standalone basis and (ii) if 

63

the arrangement includes a general right of return relative to the delivered item, delivery or performance of the 
undelivered item is considered probable and substantially within our control. In determining the separate units of 
accounting, we evaluate whether the license has standalone value to the collaborator based on consideration of the 
relevant facts and circumstances for each arrangement. Factors considered in this determination include the research 
and development capabilities of the collaborator and the availability of relevant research expertise in the 
marketplace. In addition, we consider whether or not (i) the collaborator can use the license for its intended purpose 
without the receipt of the remaining deliverables, (ii) the value of the license is dependent on the undelivered items, 
and (iii) the collaborator or other vendors can provide the undelivered items. We may exercise significant judgment 
in determining whether a deliverable is a separate unit of accounting. The arrangement consideration that is fixed or 
determinable at the inception of the arrangement is allocated to the separate units of accounting based on their 
relative selling prices. The appropriate revenue recognition model is applied to each element and revenue is 
accordingly recognized as each element is delivered. 

Royalty revenue is recognized based on contractual terms when reported sales are reliably measurable and 
collectibility is reasonably assured, provided that there are no performance obligations remaining. 

During the year ended September 30, 2016, we also generated revenue from a government contract under which we 
were reimbursed for certain allowable costs incurred for the funded project. Revenue from the government contract 
was recognized when the related service was performed. The related costs incurred by us under the government 
contract were included in research and development expense in the consolidated statements of operations. This 
contract was completed in August 2015. 

Amounts received prior to satisfying all revenue recognition criteria are recorded as deferred revenue in the 
accompanying consolidated balance sheets. Amounts not expected to be recognized as revenue within the next 
twelve months of the consolidated balance sheet date are classified as long-term deferred revenue. 

In the event that a collaborative research and license agreement is terminated and we then have no further 
performance obligations, we recognize as revenue any amounts that had not previously been recorded as revenue but 
were classified as deferred revenue at the date of such termination. 

Stock-Based Compensation - Stock Options and Restricted Stock Unit Awards

We measure stock awards with service-based conditions granted to employees and directors at fair value on the date 
of grant and recognize the corresponding stock-based compensation expense of those awards over the requisite 
service period, which is generally the vesting period of the respective award. Stock awards granted with service-
based vesting conditions, which include restricted stock units and stock options, are recorded as an expense using 
the straight-line method. In the case of performance-based options, we recognize stock-based compensation expense 
related to these awards when achievement of the underlying research and development performance-based targets 
become probable, which have typically been in the same period as when the targets are achieved.

The fair value of each restricted stock unit granted is based on the fair value of our common stock on the date of 
grant. The fair value of each stock option award is estimated on the date of grant using the Black-Scholes option-
pricing model. We only grant stock options with exercise prices equivalent to the fair value of our common stock on 
the date of grant. Generally, our expected volatility has been measured based on a combination of our historical 
stock volatility since our March 2013 IPO and the historical volatility of our publicly traded peer companies. We 
expect in fiscal 2019 to solely utilize our historical stock volatility as we will have adequate historical data regarding 
the volatility of our traded stock price following our March 2013 IPO. The expected term of our options has been 
determined utilizing the “simplified” method for awards that qualify as “plain-vanilla” options. The risk-free interest 
rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time 
periods approximately equal to the expected term of the award. Our expected dividend yield is 0 and is based on the 
fact that we have never paid cash dividends and do not expect to pay any cash dividends in the foreseeable future. 

We recognize stock-based compensation expense for only the portion of awards that vest. We recognize actual pre-
vesting forfeitures for service-based options as they occur.  

These assumptions represent our best estimates, but the estimates involve inherent uncertainties and the application 
of our judgment. As a result, if factors change and we use significantly different assumptions or estimates, our stock-
based compensation expense could be materially different. 

64

Stock-Based Compensation - Market and Performance-based Stock Unit Awards 

In addition to awards with service-based vesting conditions, we also have granted performance share units, or PSUs, 
and relative total stockholder return units, or rTSRUs, to certain of our executives. The number of units represents 
the target number of shares of common stock that may be earned; however, the actual number of shares that may be 
earned ranges from 0% to 200% or 0% to 150% of the target number, depending on the terms of the award. The fair 
value of PSUs is based on the fair value of our common stock on the date of grant. The fair value of rTSRUs is 
based on a Monte Carlo simulation model. Assumptions and estimates utilized in the calculation of the fair value of 
the rTSRUs include the risk-free interest rate, dividend yield, average closing price, expected volatility based on the 
historical volatility of publicly traded peer companies and the remaining performance period of the award. 

The PSUs vest and result in issuance, at settlement, of common shares for each recipient based upon the recipient’s 
continued employment with us through the settlement date of the award and our achievement of specified research 
and development milestones. The requisite service period of the PSUs is generally 2 years. In the case of PSUs, we 
recognize stock-based compensation expense based on the grant date fair value of the award when achievement of 
the underlying research and development performance-based targets become probable, which have typically been in 
the same period as when the targets are achieved.

The rTSRUs vest and result in the issuance of common stock based upon the recipient’s continuing employment 
with us through the settlement date of the award and the relative ranking of the total stockholder return, or TSR, of 
our common stock in relation to the TSR of the component companies in the NASDAQ Biotech Index, generally 
over a two-year period based on a comparison of average closing stock prices in specified periods noted in the award 
agreement. The fair value related to the rTSRUs is recorded as stock-based compensation expense over the period 
from date of grant to the settlement date regardless of whether the related target relative total stockholder return is 
achieved. 

Research and Manufacturing Contract Accruals

We have entered into various research and development and manufacturing contracts. These agreements are 
generally cancelable, and related payments are recorded as the corresponding expenses are incurred. We record 
accruals for estimated ongoing costs. When evaluating the adequacy of the accrued liabilities, we analyze progress 
of the research and development and manufacturing activities, including the phase or completion of events, invoices 
received and contracted costs. Significant judgments and estimates are made in determining the accrued balances at 
the end of any reporting period. Actual results could differ from our estimates. Our historical accrual estimates have 
not been materially different from the actual costs.

Income Taxes 

Income taxes are provided for tax effects of transactions reported in the consolidated financial statements and 
consist of income taxes currently due plus deferred income taxes related to timing differences between the basis of 
certain assets and liabilities for financial statement reporting purposes and the basis for income tax reporting 
purposes. Deferred taxes are determined based on the difference between the financial reporting and tax basis of 
assets and liabilities using enacted tax rates in effect in the years in which the differences are expected to reverse. 
Changes in deferred tax assets and liabilities are recorded in the provision for income taxes. 

A valuation allowance is provided if, based upon the weight of available evidence, it is more likely than not that 
some or all of the deferred tax assets will not be realized. At each balance sheet date, we assess the likelihood that 
deferred tax assets will be realized and recognize a valuation allowance if it is more likely than not that some portion 
of the deferred tax assets will not be realized. Assessment of the potential recovery of deferred tax assets requires 
judgment and is evaluated by estimating the future taxable income expected and considering prudent and feasible 
tax planning strategies. As of September 30, 2018, we continue to believe it is more likely than not that we will be 
able to realize our deferred tax assets and therefore no valuation allowance has been recorded.

Uncertain tax positions represent tax positions for which reserves have been established. We account for uncertainty 
in income taxes recognized in the consolidated financial statements by applying a two-step process to determine the 
amount to be recognized. First, the tax position must be evaluated to determine the likelihood that it will be 
sustained upon external examination by the taxing authorities. If the tax position is deemed more likely than not to 

65

be sustained, the tax position is then assessed to determine the amount to be recognized in the financial statements. 
The amount that may be recognized is the largest amount that has a greater than 50% likelihood of being realized 
upon ultimate settlement. Income tax expense includes the effects of any resulting tax reserves, or unrecognized tax 
benefits, that are considered appropriate as well as the related net interest and penalties. 

Results of Operations 

Comparison of Years Ended September 30, 2018, 2017, and 2016 

Revenue
Research and development
General and administrative
Other income (expense):

Interest income (expense), net
Change in fair value of warrant liability 
and Series 1 nonconvertible preferred 
stock, net

Income tax expense

Years Ended September 30,

2018

2017

2016

 $

206,625 
94,856 
23,441 

(in thousands)
 $

102,814 
57,451 
20,749 

 $

88,268 
40,461 
16,966 

4,852 

2,492 

1,690 

(59)   
(21,165)   

(159)   
(9,237)   

29 
(10,894)

Revenue. We recognized revenue of $206.6 million during the year ended September 30, 2018, as compared to 
$102.8 million during the year ended September 30, 2017. The increase in revenue of $103.8 million year-over-year 
was due to increased royalties of $153.8 million earned under our AbbVie agreement as a result of the launch of 
MAVYRET/MAVIRET in late 2017, which was partially offset by lower milestone revenue earned in fiscal 2018 
under our AbbVie agreement based on timing of milestone payments earned for MAVYRET/MAVIRET 
commercialization regulatory approvals. During the years ended September 30, 2018 and 2017, we recognized 
royalty revenue of $191.6 million and $37.8 million, respectively. Substantially all of our royalties earned in fiscal 
2018 were related to royalties earned on the portion of AbbVie’s net sales of MAVRYET/MAVIRET. Our fiscal 
2017 royalties were primarily based on royalties earned on the portion of AbbVie’s net sales of paritaprevir-
containing regimen, which carry a lower royalty allocation rate compared to MAVYRET/MAVIRET. 
MAVYRET/MAVIRET has become a leading HCV treatment in the U.S. and the countries where it is approved and 
has resulted in our cumulative annual royalties earned in calendar 2018 reaching the 17% royalty tier per our 
calendar year royalty rate schedule under our agreement with AbbVie. 

We recognized revenue of $102.8 million during the year ended September 30, 2017 compared to $88.3 million 
during the year ended September 30, 2016. In fiscal 2017, we earned and received milestone payments totaling 
$65.0 million as a result of commercialization regulatory approvals for MAVYRET/MAVIRET in the EU and U.S. 
In early fiscal 2016, we earned and received a $30.0 million milestone payment as a result of commercialization 
regulatory approval for AbbVie’s paritaprevir-containing regimen in Japan. We earned royalties of $37.8 million 
and $57.7 million during the years ended September 30, 2017 and 2016, respectively, primarily based on the portion 
of AbbVie’s net sales of its HCV regimens allocable to paritaprevir. We recognized lower royalty revenue in 2017 
compared to 2016 due to lower sales of paritaprevir-containing regimens as a result of increased competition from 
other HCV products on the market. We began earning royalties on the portion of AbbVie’s net sales of glecaprevir-
containing regimens in the fourth quarter of fiscal 2017.

Our royalty revenues eligible to be earned in the future will be dependent on AbbVie’s HCV market share, the 
pricing of the MAVYRET/MAVIRET regimen and the number of patients treated. In addition, at the beginning of 
each calendar year (the second quarter of our fiscal year), our royalty rates reset to the lowest tier for each of our 
royalty-bearing products licensed to AbbVie. (See Note 7 to our consolidated financial statements for further details 
on our royalty rate tier.)

66

 
 
 
 
 
 
 
 
 
 
 
 
 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
Research and development expenses. 

2018

Years Ended September 30,
2017
(in thousands)

2016

R&D programs:
Liver disease
Virology
Other
Total research and development expenses

 $

 $

54,691   $
40,047    
118    
94,856   $

34,750   $
22,399    
302    
57,451   $

17,840 
21,692 
929 
40,461  

Research and development expense increased by $37.4 million for the year ended September 30, 2018 as compared 
to the same period in 2017. The increase was primarily due to progression of preclinical and clinical activities in our 
liver disease and virology programs. In fiscal 2018 we initiated two Phase 2 studies of EDP-305 and advanced other 
compounds in preclinical development in our liver program. In fiscal 2018 we completed a Phase 1 clinical study of 
EDP-938 and prepared for a Phase 2a challenge study of EDP-938, which we initiated in October 2018, in our 
virology program. In November 2018, we announced our first clinical candidate for HBV, also in our virology 
program. Increases in our research and development expenses were driven by an increase in headcount to support 
our programs and an increase in external costs for clinical and preclinical activities. 

Research and development expenses increased by $17.0 million for the year ended September 30, 2017 as compared 
to the same period in 2016. The increase was primarily due to progression of preclinical and clinical activities in our 
liver disease and virology programs. Increases were driven by an increase in headcount to support our preclinical 
activities, expansion of our research facility and an increase in external costs for clinical and preclinical activities.

We expect that our research and development expenses will continue to increase in the future as we advance our 
RSV, NASH, PBC and HBV programs. 

General and administrative expenses. General and administrative expenses increased by $2.7 million for the year 
ended September 30, 2018 as compared to the same period in 2017. The increase was primarily due to an increase in 
compensation expense due to increased headcount and to a lesser extent an increase in external accounting and 
consulting fees. 

General and administrative expenses increased by $3.8 million for the year ended September 30, 2017 as compared 
to the same period in 2016. The increase was primarily due to an increase in compensation expense due to increased 
headcount as well as the achievement of milestones in 2017 under existing performance-based stock unit awards in 
2017.

We expect our general and administrative expenses will continue to increase in the future as our operations grow to 
support further research and development

Other income (expense). Changes in components of other income (expense) were as follows: 

Interest income (expense), net. Interest income (expense), net, increased by $2.4 million for the year ended 
September 30, 2018 as compared to the same period in 2017, primarily due to higher average investment balances in 
2018 as a result of receipt of significant milestones and royalties in 2018 under our AbbVie agreement and an 
increase in interest rates for fiscal 2018 as compared to the same period in 2017.

Interest income (expense), net, increased by $0.8 million for the year ended September 30, 2017 as compared to the 
same period in 2016 primarily due to higher average investment balances in fiscal 2017 as compared to the same 
period in 2016. 

Change in fair value of warrant liability and Series 1 nonconvertible preferred stock. We recognized other expense 
of $0.1 million and expense of $0.2 million for the years ended September 30, 2018 and 2017, respectively. We 
recognized expense in fiscal 2018 due to the increase in fair value of outstanding Series 1 nonconvertible preferred 

67

 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
     
     
  
  
  
stock year over year, offset by the expiration of unexercised warrants outstanding as of October 4, 2017. We 
recognized expense in our fiscal 2017 due to an increase in fair value of the outstanding liabilities year over year and 
income in our fiscal 2016 due to a decrease in fair value of the outstanding liabilities year over year. 

Income tax expense. Income tax expense was $21.2 million and $9.2 million for the years ended September 30, 
2018 and 2017, respectively. The effective tax rates for the years ended September 30, 2018 and 2017 were 22.7% 
and 34.3%, respectively. The increase in income tax expense was primarily due to an increase in income before 
income taxes as a result of an increase in royalties earned under our AbbVie agreement year over year as well as a 
revaluation adjustment against deferred tax assets due to a decrease in the federal corporate income tax rate as 
enacted under the U.S. Tax Cuts and Jobs Act (the “Tax Act”) in December 2017. The decrease in the effective tax 
rate was primarily due to the enactment of the Tax Act in December 2017, which decreased the U.S. federal 
statutory rate from 35.0% to 21.0%, as well as an increase in federal research and development tax credits as part of 
our advancement of our wholly-owned research and development programs and tax benefits from stock option 
exercises and restricted stock units vesting during 2018. 

Estimates used to prepare our 2018 income tax expense are based on our analysis of the Tax Act. Given the 
complexity of the Tax Act, anticipated guidance from the U.S. Treasury regarding implementation of the act, and 
potential for guidance from the Securities and Exchange Commission or the Financial Accounting Standards 
Board related to the act, these estimates may be adjusted during our fiscal 2019 to reflect any such guidance 
provided.

Income tax expense was $9.2 million and $10.9 million for the years ended September 30, 2017, and 2016, 
respectively. The effective tax rates for the years ended September 30, 2017 and 2016 were 34.3%, and 33.5%, 
respectively. The decrease in income tax expense was primarily due to lower income before income taxes as well as 
an increase in federal research and development tax credits which were deductible for tax purposes. The increase in 
the effective tax rate was primarily due to an increase in non-deductible stock-based compensation expense but was 
partially offset by an increase in federal research and development credits as part of our advancement of our wholly-
owned research and development programs in 2017.   

Income tax expense for all periods presented was attributable to the tax provision on the earnings of our operations, 
all of which are domestic.

Liquidity and Capital Resources 

During fiscal 2018, 2017 and 2016, we funded our operations with cash flows generated from operations. At 
September 30, 2018, our principal sources of liquidity were cash and cash equivalents and marketable securities of 
$325.1 million. 

The following table shows a summary of our cash flows for each of the years ended September 30, 2018, 2017, and 
2016: 

2018

Years Ended September 30,
2017
(in thousands)

2016

Cash provided by (used in):
Operating activities
Investing activities
Financing activities
Net increase (decrease) in cash and cash 
equivalents

 $

 $

29,220 
 $
(35,402)  
4,409 

52,653 
 $
(4,572)  
1,017 

35,809 
(43,663)
2,705 

(1,773)  $

49,098 

 $

(5,149)

68

 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 
    
 
    
 
 
 
 
 
Net cash provided by operating activities 

Cash provided by operating activities was $29.2 million for the year ended September 30, 2018 as compared to 
$52.7 million for the same period in 2017. The decrease in cash provided by operating activities was primarily 
driven by an increase in accounts receivable due to the timing of payments received under our collaboration with 
AbbVie and by increased tax payments, partially offset by increased net income year-over-year.

The increase in cash provided by operating activities of $16.8 million for the year ended September 30, 2017 as 
compared to the same period in 2016 was primarily driven by a $15.9 million increase in cash receipts under our 
collaboration with AbbVie. We received $105.1 million in cash from AbbVie during 2017, including royalties and 
$65.0 million in milestone payments, compared to $89.2 million in cash during 2016, including royalties and a $30.0 
million milestone payment. In addition, our taxes paid, net of refunds received, decreased by $17.5 million, due to 
lower profit before tax and timing of tax payments and refunds. These increases were partially offset by increased 
cash spending on research and development during 2017 in order to progress clinical development and preclinical 
research in our proprietary programs.

Net cash used in investing activities 

The increase in cash used in investing activities of $30.8 million for the year ended September 30, 2018 as compared 
to the same period in 2017 was driven by timing of purchases, sales and maturities of marketable securities. 

The decrease in cash used in investing activities of $39.1 million for the year ended September 30, 2017 as 
compared to the same period in 2016 was driven by timing of purchases, sales and maturities of marketable 
securities. In addition, our capital asset outlay decreased by $2.2 million year over year due to the expansion of our 
research facility which was completed in fiscal 2016. 

Net cash provided by financing activities 

The increase in cash provided by financing activities of $3.4 million for the year ended September 30, 2018 as 
compared to the same period in 2017 was driven primarily by an increase in proceeds from stock option exercises as 
a result of the increase in the price of our common stock year over year and was partially offset by an increase in tax 
withholding payments for the vesting of performance-based stock unit awards in 2018.

The decrease in cash provided by financing activities of $1.7 million for the year ended September 30, 2017 as 
compared to the same period in 2016 was driven primarily by tax withholding payments for the vesting of 
performance-based stock unit awards in 2017 and a lower income tax benefit from stock options exercised in fiscal 
2017 as compared to fiscal 2016. 

Funding Requirements 

As of September 30, 2018, we had $325.1 million in cash, cash equivalents and short-term and long-term marketable 
securities. We believe that our existing cash, cash equivalents and marketable securities as of September 30, 2018 
will be sufficient to meet our anticipated cash requirements for the foreseeable future. However, our forecast of the 
period of time through which our financial resources will be adequate to support our operations is a forward-looking 
statement that involves risks and uncertainties, and actual results could vary materially. 

Our future capital requirements are difficult to forecast and will depend on many factors, including: 

(cid:129)

(cid:129)

(cid:129)

(cid:129)

the amount of royalties generated from our existing collaboration with AbbVie;

the number and characteristics of the future product candidates we pursue; 

the scope, progress, results and costs of researching and developing any of our product candidates on 
our own, including conducting advanced clinical trials;

the cost of manufacturing our product candidates and any products we successfully commercialize 
independently, including manufacturing for clinical development;

69

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

(cid:129)

opportunities to in-license or otherwise acquire new technologies, therapeutic candidates and therapies;

the timing and amount of royalties and any sales of our product candidates, if any, or royalties thereon;

the timing of, and the costs involved in, obtaining regulatory approvals for any product candidates we 
develop independently;

the cost of commercialization activities, if any, of any product candidates we develop independently that 
are approved for sale, including marketing, sales and distribution costs;

our ability to establish new collaborations, licensing or other arrangements, if any, and the financial 
terms of such agreements; and

the costs involved in preparing, filing, prosecuting, maintaining, defending and enforcing patents, 
including any litigation costs and the outcomes of any such litigation.

potential fluctuations in foreign currency exchange rates; 

We do not believe that inflation had a material effect on our business, financial condition or results of operations in 
the last three fiscal years. If our costs were to become subject to significant inflationary pressures, we could not 
offset such higher costs through revenue increases because our revenues are substantially outside of our control. Our 
inability to do so could harm our business, financial condition and results of operations. 

Off-Balance Sheet Arrangements 

We do not engage in any off-balance sheet financing activities. We do not have any interest in entities referred to as 
variable interest entities, which include special purpose entities and other structured finance entities. 

Recently Issued Accounting Pronouncements 

A description of recently issued accounting pronouncements that may potentially impact our financial position and 
results of operations is set forth in Note 2 to the consolidated financial statements included in this Annual Report on 
Form 10-K. 

Contractual Obligations and Commitments 

We lease space in Watertown, Massachusetts under two separate lease agreements. 

The first lease, located at 500 Arsenal Street, commenced on October 1, 2011 and was amended in 2015 to expand 
the rented space and extend the lease term through September 2022. This lease is for office and laboratory space. In 
conjunction with the amendment of the lease, the Company entered into a capital lease agreement to fund certain 
leasehold improvements and the purchase of lab equipment. 

The second lease, located at 400 Talcott Ave, commenced on September 24, 2018 for office space and extends 
through August 1, 2024. The Company estimates it will spend approximately $2.0 million in tenant and capital 
improvements to the space during fiscal 2019.  

70

The following table summarizes our contractual obligations at September 30, 2018 and the effect such obligations 
are expected to have on our liquidity and cash flow in future periods: 

Operating leases
Capital leases

Payments Due by Period

Less than 1 
year

    1-3 years     3-5 years    

More than 
5 years

Total

$

 $

2,209 
86 

5,531 
194 

(in thousands)
3,292 
 $
99 

 $

519 
— 

 $ 11,551 
379 

Total contractual 
commitments and obligations $

2,295 

 $

5,725 

 $

3,391 

 $

519 

$ 11,930  

As of September 30, 2018, we had 1.9 million outstanding shares of Series 1 nonconvertible preferred stock, all of 
which we classified as long-term liabilities on our consolidated balance sheet and recorded at fair value of $1.6 
million. The fair value of the preferred stock was measured based on significant inputs not observable in the market, 
which represented a Level 3 measurement within the fair value hierarchy. The fair value of these instruments 
represents less than 10% of liabilities measured at fair value as of September 30, 2018. The Series 1 nonconvertible 
preferred stock issued would require the payment of $2.0 million in the event of a qualifying merger or sale of the 
company. The table above does not include this liability because we are unable to estimate the timing of this 
required payment, or if it will be required at all. 

ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK 

Interest Rate Risk

We had cash, cash equivalents and marketable securities of $325.1 million at September 30, 2018, which consisted 
of cash, money market funds, agency securities, commercial paper, treasury notes and corporate bonds. Interest 
income is sensitive to changes in the general level of interest rates; however, due to the nature of these 
investments, a change in market interest rates of 100 basis points would not be expected to have a material impact 
on our financial condition or results of operations. Other than our capital lease obligation, we had no debt 
outstanding as of September 30, 2018.

Foreign Exchange Risk

As we continue to progress our wholly-owned programs into clinical development we will conduct clinical trials 
outside of the U.S. and thus will face exposure to movements in foreign currency exchange rates, primarily the 
British Pound and Euro, against the U.S. Dollar, arising from our accounts payable and accrued expenses. During 
fiscal 2018, the impact of foreign currency exposure was immaterial and thus did not have a significant impact on 
our consolidated financial statements. In fiscal 2019, we expect to face increasing exposure to the British Pound as 
we conduct our Phase 2a challenge study of EDP-938 in the U.K. However, based on our current contractual 
commitments outside of the U.S., we estimate that a change of 10% in foreign currency exchange rates would not 
materially affect our operations. Our operations may become subject to more significant fluctuations in foreign 
currency exchange rates in the future if we continue to contract with vendors outside of the U.S.

ITEM 8.

CONSOLIDATED FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA 

Our consolidated financial statements, together with the report of our independent registered public accounting firm, 
appear on pages F-1 through F-32 of this Annual Report on Form 10-K. 

ITEM 9.

None. 

CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND 
FINANCIAL DISCLOSURE 

71

 
 
 
 
 
   
 
 
 
 
  
  
  
  
 
ITEM 9A. CONTROLS AND PROCEDURES 

Conclusion Regarding the Effectiveness of Disclosure Controls and Procedures 

We maintain disclosure controls and procedures that are designed to ensure that information required to be disclosed 
in the Company’s reports under the Securities Exchange Act of 1934, as amended (the Exchange Act), is recorded, 
processed, summarized and reported within the time periods specified in the SEC’s rules and forms, and that such 
information is accumulated and communicated to management, including our Chief Executive Officer (CEO) and 
Chief Financial Officer (CFO), as appropriate, to allow timely decisions regarding required disclosure. In designing 
and evaluating the disclosure controls and procedures, management recognized that any controls and procedures, no 
matter how well designed and operated, can provide only reasonable assurance of achieving the desired control 
objectives, as the Companies are designed to do, and management necessarily was required to apply its judgment in 
evaluating the risk related to controls and procedures. 

In connection with the preparation of this Form 10-K, as of September 30, 2018, an evaluation was performed under 
the supervision and with the participation of our management, including the CEO and CFO, of the effectiveness of 
the design and operation of our disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) 
under the Exchange Act). Based on that evaluation, our management concluded that our disclosure controls and 
procedures were effective at a reasonable assurance level as of September 30, 2018. These conclusions were 
communicated to the Audit Committee. 

Management’s Report on Internal Control Over Financial Reporting 

Our management is responsible for establishing and maintaining adequate internal control over financial reporting as 
defined in Rule 13a-15(f) and Rule 15d-15(f) under the Exchange Act. Our internal control system is designed to 
provide reasonable assurance to the Company’s management and Board of Directors regarding the preparation and 
fair presentation of published financial statements. All internal control systems, no matter how well designed, have 
inherent limitations. Therefore, even those systems determined to be effective can provide only reasonable assurance 
with respect to financial statement preparation and presentation. 

Our management has assessed the effectiveness of our internal control over financial reporting as of September 30, 
2018. In making this assessment, management used the criteria set forth by the Committee of Sponsoring 
Organizations of the Treadway Commission (COSO) in its 2013 Internal Control—Integrated Framework. Based on 
this assessment, our management has concluded that as of September 30, 2018 our internal control over financial 
reporting is effective. 

The effectiveness of the Company’s internal control over financial reporting as of September 30, 2018, has been 
audited by PricewaterhouseCoopers LLP, an independent registered public accounting firm, as stated in their report 
which appears in Item 8 above. 

Change in Internal Control over Financial Reporting—There were no changes in our internal control over financial 
reporting that occurred during our last quarter that have materially affected, or are reasonably likely to materially 
affect, our internal control over financial reporting. 

ITEM 9B. OTHER INFORMATION 

None. 

72

PART III 

ITEM 10. DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE 

Portions of the response to this item are incorporated herein by reference from the discussion responsive thereto 
under the captions “Proposal 1 - Election of Directors—Nominees for Director and Current Directors”, “Section 
16(a) Beneficial Ownership Reporting Compliance”, “Executive Officers” and “Corporate Governance—Board and 
Committee Matters” in the Company’s Definitive Proxy Statement relating to the 2019 Annual Meeting of 
Stockholders, also referred to as the 2019 Proxy Statement, which will be filed within 120 days after September 30, 
2018.

We have adopted a Code of Business Conduct and Ethics (the code of ethics) that applies to all of our directors, 
officers and employees. The code of ethics is available on our website at http://www.enanta.com. In addition, if we 
make any substantive amendments to the code of ethics or grant any waiver, including any implicit waiver, from a 
provision of the code to any of our executive officers or directors, we will disclose the nature of such amendment or 
waiver as required by applicable law. 

ITEM 11.

EXECUTIVE COMPENSATION 

The response to this item is incorporated herein by reference from the discussion responsive thereto under the 
following captions in the 2019 Proxy Statement: “Executive Compensation” and “Corporate Governance—Certain 
Relationships and Related Transactions.” 

ITEM 12.

SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT 
AND RELATED STOCKHOLDER MATTERS 

The response to this item is incorporated herein by reference in part from the discussion responsive thereto under the 
caption “Beneficial Ownership of Common Stock” in the 2019 Proxy Statement. 

The following table provides information about the securities authorized for issuance under the Company’s equity 
compensation plans as of September 30, 2018: 

Equity Compensation Plan Information 

(in thousands, except per share information)

Plan Category

Equity compensation plans approved by 
security holders (1)
Equity compensation plans not approved by 
security holders
Totals

Number of securitie
s
to be issued
upon exercise of
outstanding options,
warrants and rights  
(a)

Weighted
average
exercise price of
outstanding
options,
warrants and
rights
(b)

Number of securities
remaining available for
future issuance under
equity compensation plan
s
(excluding securities
reflected in column (a))
(c)

2,873  (2)

$ 33.47 

—  
2,873  

—  

437  (3)

—  
437  

(1) Consists of, the Company’s 2012 Equity Incentive Plan, as amended, the Company’s Amended and Restated 

1995 Equity Incentive Plan, as amended, and the Company’s Employee Stock Purchase Plan. 

(2) Consists of shares of the Company’s common stock issuable upon exercise of outstanding options issued 

under the Company’s 2012 Equity Incentive Plan, and the Company’s Amended and Restated 1995 Equity 
Incentive Plan.

73

 
 
 
 
   
 
 
 
 
 
 
   
  
  
 
 
 
 
 
 
   
  
 
 
(3) Consists of shares of the Company’s common stock reserved for future issuance under the Company’s 2012 
Equity Incentive Plan and the Company’s Employee Stock Purchase Plan. This does not include 583 shares 
that were automatically added to the Company’s 2012 Equity Incentive Plan by its terms as of October 1, 
2018. 

ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTOR 

INDEPENDENCE 

The response to this item is incorporated herein by reference from the discussion responsive thereto under the 
caption “Corporate Governance—Certain Relationships and Related Transactions” and “Corporate Governance—
Board and Committee Matters” in the 2019 Proxy Statement. 

ITEM 14.

PRINCIPAL ACCOUNTANT FEES AND SERVICES 

The response to this item is incorporated herein by reference from the discussion responsive thereto under the 
captions “Corporate Governance—Board and Committee Matters” and “Audit Committee Report—Audit Fees” in 
the 2019 Proxy Statement. 

PART IV 

ITEM 15.

EXHIBITS, FINANCIAL STATEMENT SCHEDULES 

(a) 1. FINANCIAL STATEMENTS 

The financial statements are included under Part II, Item 8 of this Report. 

2. FINANCIAL STATEMENTS SCHEDULE 

Schedules are omitted because they are not applicable, or are not required, or because the information is included in 
the consolidated financial statements and notes thereto. 

3. EXHIBITS – 

The exhibits are listed below under Part IV, Item 15(b) of this Report. 

(b) EXHIBITS 

Exhibit
Number
3.1

3.2

4.1

4.2

Exhibit Description
Restated Certificate of Incorporation of Enanta 
Pharmaceuticals, Inc.
Amended and Restated Bylaws of Enanta 
Pharmaceuticals, Inc. (as amended and restated 
in August 2015).
Specimen certificate evidencing shares of 
common stock.
Specimen certificate evidencing shares of Series 
1 Non-Convertible Preferred Stock 

Incorporated by Reference

Form
8-K

Date
03/28/2013

Exhibit
Number
3.1

Filed
Herewith 

File Number
001-35839  

8-K

08/18/2015

3.2

001-35839  

S-1/A

02/05/2013

10-K

12/11/2017

4.1

4.3

333-184779  

001-35839

10.1# Form of Indemnification Agreement for 

S-1/A

02/05/2013

10.7

333-184779  

directors and officers.

10.2# Amended and Restated Employment Agreement 

S-1/A

03/05/2013

10.5

333-184779  

between the Company and Jay R. Luly, Ph.D., 
dated as of March 4, 2013.

10.3# Form of Amended and Restated Employment 
Agreement for Executive Officers other than 
the Chief Executive Officer.

S-1/A

03/05/2013

10.17

333-184779  

74

 
 
 
Exhibit
Number
10.4† Collaborative Development and License 

Exhibit Description

Form
10-Q

Date
02/09/2016

Exhibit
Number
10.1

File Number
001-35839

Filed
Herewith 

Incorporated by Reference

Agreement between the Company and Abbott 
Laboratories, dated November 27, 2006; as 
amended by a First Amendment to Collaborative 
Development and License Agreement dated 
January 27, 2009 and a Second Amendment to 
Collaborative Development and License 
Agreement dated December 9, 2009 (assigned to 
AbbVie Inc. as of January 1, 2013).

10.5† Third Amendment to Collaborative Development 

10-K

12/11/2014

10.5

001-35839

and License Agreement between the Company and 
AbbVie dated October 20, 2014.
Fourth Amendment to Collaborative Development 
and License Agreement between the Company and 
AbbVie dated as of March 3, 2015.
Lease Agreement between Company and ARE-
500 Arsenal Street LLC, dated as of April 15, 
2011.
First Amendment to Lease Agreement made as 
of March 5, 2015 between the Company and 
ARE-500 Arsenal Street LLC.
Third Amended and Restated Registration 
Rights Agreement, dated as of August 23, 2012.

10.6

10.7

10.8

10.9

10.10 Lease Agreement between Company and 

Athena Arsenal, LLC, dated as of September 
27, 2018.

10-Q

05/08/2015

10.1

001-35839  

S-1

11/06/2012

10.6

333-184779  

10-Q

05/08/2015

10.2

001-35839  

S-1/A

11/06/2012

10.4

333-184779  

10.10# Amended and Restated 1995 Equity Incentive 

S-1/A

03/05/2013

10.8

333-184779  

Plan.

10.11# Form of Incentive Stock Option Certificate 
under Amended and Restated 1995 Equity 
Incentive Plan.

10.12# Form of Non-Statutory Stock Option Certificate 
under Amended and Restated 1995 Equity 
Incentive Plan.

10.13# Form of Non-Statutory Stock Option Certificate 
for directors under Amended and Restated 1995 
Equity Incentive Plan.

S-1/A

03/05/2013

10.9

333-184779  

S-1/A

03/05/2013

10.10

333-184779  

S-1/A

03/05/2013

10.11

333-184779  

10.14# 2012 Equity Incentive Plan (As adjusted to 

10-K/A 01/06/2017

10.14

001-35839  

reflect the application of the 1-for-4.31 reverse 
stock split of the Company’s common stock 
effected on March 1, 2013).

10.15# Form of Incentive Stock Option Agreement 
under 2012 Equity Incentive Plan.

S-1/A

03/05/2013

10.13

333-184779  

10.16# Form of Non-Statutory Stock Option Agreement 

S-1/A

03/05/2013

10.14

333-184779  

under 2012 Equity Incentive Plan.

10.17# Form of Non-Statutory Stock Option Certificate 

S-1/A

03/05/2013

10.15

333-184779  

for directors under 2012 Equity Incentive Plan.

10.18# Form of Performance Share Unit Certificate 

10-K

12/11/2017

10.18

001-35839

under 2012 Equity Incentive Plan.

10.19# Form of Relative Total Stockholder Return Unit 

10-K

12/11/2017

10.19

001-35839

Certificate under 2012 Equity Incentive Plan.

10.20# Employee Stock Purchase Plan.
21.1

Subsidiaries of the Company.

S-1/A

02/05/2013

10.16

333-184779  

X

X

75

 
 
 
 
 
 
 
Incorporated by Reference

Exhibit
Number

File Number

Filed
Herewith 
X

X

X

X

X

Exhibit
Number
23.1

31.1

31.2

32.1

101

Exhibit Description

Form

Date

Consent of PricewaterhouseCoopers LLP, 
Independent Registered Public Accounting 
Firm.
Certification of the Chief Executive Officer 
pursuant to Rule 13a-14(a) or 15d-14(a) of the 
Securities Exchange Act of 1934.
Certification of Chief Financial Officer pursuant 
to Rule 13a-14(a) or 15d-14(a) of the Securities 
Exchange Act of 1934.
Certification of the Chief Executive Officer and 
Chief Financial Officer pursuant to 18 U.S.C. 
Section 1350, as adopted pursuant to 
Section 906 of the Sarbanes-Oxley Act of 2002.
The following materials from the Annual Report 
of Enanta Pharmaceuticals, Inc. on Form 10-K 
for the year ended September 30, 2018 
formatted in XBRL (eXtensible Business 
Reporting Language): (i) Consolidated Balance 
Sheets as of September 30, 2018 and September 
30, 2017 of Enanta Pharmaceuticals, Inc., (ii) 
Consolidated Statements of Operations for the 
years ended September 30, 2018, 2017, and 
2016 of Enanta Pharmaceuticals, Inc., (iii) 
Consolidated Statements of Comprehensive 
Income for the years ended September 30, 2018, 
2017, and 2016 of Enanta Pharmaceuticals, Inc., 
(iv) Consolidated Statements of Stockholders’ 
Equity for the years ended September 30, 2018, 
2017, and 2016 of Enanta Pharmaceuticals, Inc., 
(v) Consolidated Statements of Cash Flows for 
the years ended September 30, 2018, 2017, and 
2016 of Enanta Pharmaceuticals, Inc., and 
(vi) Notes to Consolidated Financial Statements 
of Enanta Pharmaceuticals, Inc.

#
†

††

Management contract or compensatory plan, contract or agreement. 
Confidential treatment granted as to portions of this Exhibit. The confidential portions of this Exhibit have 
been omitted and are marked by asterisks. 
This Exhibit has been filed separately with the commission pursuant to an application for confidentiality 
treatment. The confidential portions of this Exhibit have been omitted and are marked by asterisks. 

ITEM 16.

FORM 10-K SUMMARY 

 None.

76

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
SIGNATURES 

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the Company has duly 
caused this report to be signed on its behalf by the undersigned, thereunto duly authorized, this 29th day of 
November, 2018. 

ENANTA PHARMACEUTICALS, INC.

By:

/s/ Jay R. Luly, Ph.D.      
Jay R. Luly, Ph.D.
Chief Executive Officer

Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the 
following persons on behalf of the Company in the capacities and on the dates indicated. 

Signature

Title

Date

/s/ Jay R. Luly, Ph.D.      
Jay R. Luly, Ph.D.

/s/ Paul J. Mellett       
Paul J. Mellett

President and Chief Executive
Officer and Director
(Principal Executive Officer)

Chief Financial Officer
(Principal Financial and
Accounting Officer)

/s/ Stephen Buckley, Jr.        
Stephen Buckley, Jr.

/s/ Bruce L.A. Carter, Ph.D.       

Bruce L.A. Carter, Ph.D.

/s/ George S. Golumbeski, Ph.D.       

George S. Golumbeski, Ph.D.

/s/ Kristine Peterson       

Kristine Peterson

/s/ Lesley Russell, MB. Ch.B., MRCP      

Lesley Russell, MB. Ch.B., MRCP

/s/ Terry Vance      

Terry Vance

Director

Director

Director

Director

Director

Director

 November 29, 2018

 November 29, 2018

 November 29, 2018

 November 29, 2018

 November 29, 2018

 November 29, 2018

 November 29, 2018

 November 29, 2018

77

 
 
 
 
 
 
 
 
 
 
ENANTA PHARMACEUTICALS, INC. 

INDEX TO CONSOLIDATED FINANCIAL STATEMENTS 

Report of Independent Registered Public Accounting Firm
Consolidated Balance Sheets
Consolidated Statements of Operations
Consolidated Statements of Comprehensive Income
Consolidated Statements of Stockholders’ Equity 
Consolidated Statements of Cash Flows
Notes to Consolidated Financial Statements

Page
F-2
F-4
F-5
F-6
F-7
F-8
F-9

F-1

 
 
 
ITEM 8.

FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA 

Report of Independent Registered Public Accounting Firm 

To the Board of Directors and Stockholders of
Enanta Pharmaceuticals, Inc.

Opinions on the Financial Statements and Internal Control over Financial Reporting

We have audited the accompanying consolidated balance sheets of Enanta Pharmaceuticals, Inc. and its subsidiary 
(“the Company”) as of September 30, 2018 and 2017, and the related consolidated statements of operations, 
comprehensive income, stockholders’ equity and cash flows for each of the three years in the period ended 
September 30, 2018, including the related notes (collectively referred to as the “consolidated financial statements”).  
We also have audited the Company's internal control over financial reporting as of September 30, 2018, based on 
criteria established in Internal Control - Integrated Framework (2013) issued by the Committee of Sponsoring 
Organizations of the Treadway Commission (COSO).  

In our opinion, the consolidated financial statements referred to above present fairly, in all material respects, the 
financial position of the Company as of September 30, 2018 and 2017, and the results of its operations and its cash 
flows for each of the three years in the period ended September 30, 2018 in conformity with accounting principles 
generally accepted in the United States of America.  Also in our opinion, the Company maintained, in all material 
respects, effective internal control over financial reporting as of September 30, 2018, based on criteria established in 
Internal Control - Integrated Framework (2013) issued by the COSO.

Basis for Opinions

The Company's management is responsible for these consolidated financial statements, for maintaining effective 
internal control over financial reporting, and for its assessment of the effectiveness of internal control over financial 
reporting, included in Management’s Report on Internal Control Over Financial Reporting under Item 9A. Our 
responsibility is to express opinions on the Company’s consolidated financial statements and on the Company's 
internal control over financial reporting based on our audits.  We are a public accounting firm registered with the 
Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with 
respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations 
of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB.  Those standards require that we plan and 
perform the audits to obtain reasonable assurance about whether the consolidated financial statements are free of 
material misstatement, whether due to error or fraud, and whether effective internal control over financial reporting 
was maintained in all material respects.  

Our audits of the consolidated financial statements included performing procedures to assess the risks of material 
misstatement of the consolidated financial statements, whether due to error or fraud, and performing procedures that 
respond to those risks.  Such procedures included examining, on a test basis, evidence regarding the amounts and 
disclosures in the consolidated financial statements.  Our audits also included evaluating the accounting principles 
used and significant estimates made by management, as well as evaluating the overall presentation of the 
consolidated financial statements.  Our audit of internal control over financial reporting included obtaining an 
understanding of internal control over financial reporting, assessing the risk that a material weakness exists, and 
testing and evaluating the design and operating effectiveness of internal control based on the assessed risk.  Our 
audits also included performing such other procedures as we considered necessary in the circumstances. We believe 
that our audits provide a reasonable basis for our opinions.

F-2

Definition and Limitations of Internal Control over Financial Reporting

A company’s internal control over financial reporting is a process designed to provide reasonable assurance 
regarding the reliability of financial reporting and the preparation of financial statements for external purposes in 
accordance with generally accepted accounting principles.  A company’s internal control over financial reporting 
includes those policies and procedures that (i) pertain to the maintenance of records that, in reasonable detail, 
accurately and fairly reflect the transactions and dispositions of the assets of the company; (ii) provide reasonable 
assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance 
with generally accepted accounting principles, and that receipts and expenditures of the company are being made 
only in accordance with authorizations of management and directors of the company; and (iii) provide reasonable 
assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s 
assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements.  
Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become 
inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may 
deteriorate.

/s/ PricewaterhouseCoopers LLP
Boston, Massachusetts
November 29, 2018

We have served as the Company’s auditor since 1999.

F-3

ENANTA PHARMACEUTICALS, INC. 

CONSOLIDATED BALANCE SHEETS 
(in thousands, except per share data) 

Assets
Current assets:

Cash and cash equivalents
Short-term marketable securities
Accounts receivable
Prepaid expenses and other current assets

Total current assets
Long-term marketable securities
Property and equipment, net
Deferred tax assets
Restricted cash
Other long-term assets

Total assets

Liabilities and Stockholders' Equity
Current liabilities:

Accounts payable
Accrued expenses and other current liabilities
Income taxes payable

Total current liabilities

Warrant liability
Series 1 nonconvertible preferred stock
Other long-term liabilities

Total liabilities

Commitments and contingencies (Note 12)
Stockholders' equity:

Common stock; $0.01 par value per share, 100,000 shares authorized;  
19,395 and 19,120 shares issued and outstanding at September 30, 2018 
and September 30, 2017, respectively
Additional paid-in capital
Accumulated other comprehensive loss
Retained earnings

Total stockholders' equity
Total liabilities and stockholders' equity

September 30,
2018

September 30,
2017

  $

  $

  $

  $

63,902    $
244,828   
67,205   
4,454   
380,389   
16,389   
8,374   
8,375   
608   
92   

414,227    $

4,745    $
9,892   
1,388   
16,025   
—   
1,628   
2,895   
20,548   

65,675 
157,994 
10,614 
3,536 
237,819 
70,038 
8,049 
10,123 
608 
— 
326,637 

3,714 
7,970 
9,298 
20,982 
807 
762 
2,410 
24,961 

194   
276,526   
(398)  
117,357   
393,679   
414,227    $

191 
256,241 
(112)
45,356 
301,676 
326,637  

The accompanying notes are an integral part of these consolidated financial statements.

F-4

 
 
 
   
 
 
 
   
 
 
 
 
   
 
 
 
 
 
 
   
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
    
   
 
 
   
   
   
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   
   
   
 
 
 
    
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
ENANTA PHARMACEUTICALS, INC. 

CONSOLIDATED STATEMENTS OF OPERATIONS 
(in thousands, except per share data) 

Revenue

Royalties
Milestones
Other

Total revenue
Operating expenses:

Research and development
General and administrative

Total operating expenses

Income from operations
Other income (expense):

Interest income (expense), net
Change in fair value of warrant liability and Series 1 
nonconvertible preferred stock

Total other income (expense), net

Income before income taxes
Income tax expense

Net income
Net income per share:

Basic
Diluted

Weighted average shares outstanding:

Basic
Diluted

 $

  $

 $
 $

Years Ended September 30,
2017

2016

2018

191,625 
15,000 
— 
206,625 

94,856 
23,441 
118,297 
88,328 

 $

 $

37,814 
65,000 
— 
102,814 

57,451 
20,749 
78,200 
24,614 

57,692 
30,000 
576 
88,268 

40,461 
16,966 
57,427 
30,841 

4,852 

2,492 

1,690 

(59)   

4,793 
93,121 
(21,165)   
 $
71,956 

(159)   
2,333 
26,947 
(9,237)   
 $
17,710 

3.74 
3.48 

 $
 $

0.93 
0.91 

 $
 $

19,255 
20,650 

19,066 
19,407 

29 
1,719 
32,560 
(10,894)
21,666 

1.14 
1.13 

18,929 
19,224  

The accompanying notes are an integral part of these consolidated financial statements. 

F-5

 
 
 
 
 
 
 
 
 
 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
   
  
  
  
  
  
  
  
  
  
   
  
  
   
  
  
  
   
  
  
  
  
  
   
  
  
  
  
  
  
  
  
  
  
  
ENANTA PHARMACEUTICALS, INC.

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME 
(in thousands) 

Net income
Other comprehensive loss:

Years Ended September 30,
2017

2016

2018

  $

71,956    $

17,710 

 $

21,666 

Net unrealized losses on marketable securities, net of tax 
benefit of ($109), ($78), and ($9)

Total other comprehensive loss

Comprehensive income

(286)   
(286)    
71,670    $

(131)    
(131)    
17,579    $

(14)
(14)
21,652  

  $

The accompanying notes are an integral part of these consolidated financial statements. 

F-6

 
 
 
 
 
 
 
 
 
 
 
     
       
       
 
   
   
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F

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
  
 
  
 
  
 
  
 
  
 
  
 
 
 
  
 
  
 
  
 
  
 
  
 
  
 
 
 
 
 
 
 
  
 
  
 
  
 
  
 
  
 
  
 
 
 
  
 
  
 
  
 
  
  
 
  
 
  
 
  
 
  
 
  
 
  
 
  
 
 
 
 
 
  
 
  
 
  
 
  
 
  
 
  
 
 
 
 
  
 
  
 
  
 
  
 
  
 
  
 
 
 
 
 
 
 
 
  
 
  
 
  
  
 
  
 
  
 
 
  
 
  
 
  
 
  
 
  
 
  
 
 
 
 
 
 
 
  
 
  
 
  
 
  
 
  
 
  
 
 
 
  
 
  
 
  
 
  
  
 
  
 
  
 
  
 
  
 
  
 
  
 
  
 
 
 
 
 
  
 
  
 
  
 
  
  
 
  
 
 
 
 
 
 
  
 
  
 
  
 
  
 
  
 
  
 
 
 
 
 
 
 
 
  
 
  
 
  
  
 
  
 
  
 
 
  
 
  
 
  
 
  
 
  
 
  
 
 
 
 
 
 
 
 
 
 
 
  
 
  
 
  
  
 
  
 
  
 
 
 
  
 
  
 
  
 
  
  
 
  
 
  
 
  
 
  
 
  
 
  
 
  
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
ENANTA PHARMACEUTICALS, INC.

CONSOLIDATED STATEMENTS OF CASH FLOWS 
(in thousands) 

Cash flows from operating activities

Net income
Adjustments to reconcile net income to net cash provided by
   operating activities:

Stock-based compensation expense
Depreciation and amortization expense
Deferred income taxes
Income tax benefit from stock awards
Premium paid on marketable securities
Amortization of (accretion of) premium (discount) on 
marketable securities
Change in fair value of warrant liability and Series 1 
nonconvertible preferred stock
Other non-cash items
Change in operating assets and liabilities:

Accounts receivable
Unbilled receivables
Prepaid expenses and other current assets
Accounts payable
Accrued expenses
Income taxes payable
Other long-term liabilities
Other long-term assets

Net cash provided by operating activities
Cash flows from investing activities
Purchase of marketable securities
Proceeds from maturities and sale of marketable securities
Purchase of property and equipment

Net cash used in investing activities
Cash flows from financing activities

Proceeds from exercise of stock options and warrants
Income tax benefit from exercise of stock options
Payments for settlement of share-based awards
Payments of capital lease obligations
Net cash provided by financing activities
Net increase (decrease) in cash and cash equivalents
Cash and cash equivalents at beginning of period
Cash and cash equivalents at end of period
Supplemental disclosure of cash flow information:

Cash paid for income taxes

Non-cash items:

Purchases of fixed assets included in accounts payable and 
accrued expenses

Years Ended September 30,
2017

2016

2018

  $

71,956    $

17,710    $

21,666 

15,845     
2,518     
1,858     
—     
(319)    

13,071     
2,137     
(1,654)    
(213)    
(1,229)    

9,354 
1,661 
(2,294)
(1,747)
(518)

(835)    

702     

1,511 

59     
(75)    

(56,591)    
—     
(918)    
1,317     
1,843     
(7,910)    
564     
(92)    
29,220     

159     
—     

2,227     
—     
5,678     
633     
3,443     
9,511     
478     
—     
52,653     

(29)
34 

2,448 
433 
(964)
1,451 
1,858 
548 
397 
— 
35,809 

(293,103)    
260,682     
(2,981)    
(35,402)    

(251,371)    
249,305     
(2,506)    
(4,572)    

(192,429)
153,504 
(4,738)
(43,663)

6,244     
—     
(1,756)    
(79)    
4,409     
(1,773)    
65,675     
63,902    $

1,079     
213 
(202)
(73)
1,017     
49,098     
16,577     
65,675    $

1,026 
1,747 
— 
(68)
2,705 
(5,149)
21,726 
16,577 

26,088    $

1,588    $

12,616 

111    $

318    $

637  

  $

  $

  $

The accompanying notes are an integral part of these consolidated financial statements. 

F-8

 
 
 
 
 
   
 
 
 
   
 
     
 
 
   
 
 
   
        
       
 
   
   
   
   
   
   
   
   
     
       
       
 
   
   
   
   
   
   
   
   
   
   
        
       
 
   
   
   
   
   
        
       
 
   
   
  
   
  
   
  
   
   
   
     
       
       
 
     
       
       
 
ENANTA PHARMACEUTICALS, INC. 

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS 
(Amounts in thousands, except per share data) 

1. Nature of the Business 

Enanta Pharmaceuticals, Inc. (the “Company”), incorporated in Delaware in 1995, is a biotechnology company that 
uses its robust, chemistry-driven approach and drug discovery capabilities to create small molecule drugs primarily 
for the treatment of viral infections and liver diseases. The Company discovered glecaprevir, the second protease 
inhibitor discovered and developed through its collaboration with AbbVie, which is marketed as part of AbbVie’s 
direct-acting antiviral (DAA) regimen under the tradenames MAVYRET™ (U.S.) or MAVIRET™ (ex-U.S.) 
(glecaprevir/pibrentasvir) for the treatment of chronic hepatitis C virus, or HCV. The other protease inhibitor under 
its HCV collaboration, which is part of AbbVie’s initial DAA regimens for the treatment of chronic HCV, is 
currently marketed outside the U.S. under the tradename VIEKIRAX® (paritaprevir/ritonavir/ombitasvir). Royalties 
from the Company’s AbbVie collaboration and its existing financial resources provide funding to support its wholly-
owned research and development programs, which are currently focused on the following disease targets: respiratory 
syncytial virus (“RSV”), non-alcoholic steatohepatitis (“NASH”); primary biliary cholangitis (“PBC”); and hepatitis 
B virus (“HBV”).

The Company is subject to many of the risks common to companies in the biotechnology industry including, but not 
limited to, the uncertainties of research and development, competition from technological innovations of others, 
dependence on collaborative arrangements, protection of proprietary technology, dependence on key personnel and 
compliance with government regulation. Product candidates currently under development will require significant 
additional research and development efforts, including extensive preclinical and clinical testing and regulatory 
approvals, prior to commercialization. These efforts require significant amounts of capital, adequate personnel 
infrastructure, and extensive compliance reporting capabilities.

2. Summary of Significant Accounting Policies 

Basis of Presentation 

The accompanying consolidated financial statements include those of the Company and its subsidiary, Enanta 
Pharmaceuticals Security Corporation, after elimination of all intercompany accounts and transactions. The 
accompanying consolidated financial statements have been prepared in conformity with accounting principles 
generally accepted in the United States of America (“GAAP”). 

Use of Estimates 

The preparation of consolidated financial statements in conformity with GAAP requires management to make 
estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent 
assets and liabilities at the date of the consolidated financial statements, and the reported amounts of revenues and 
expenses during the reporting period. Significant estimates and assumptions reflected in these consolidated financial 
statements include, but are not limited to, management’s judgments with respect to its revenue arrangements; 
valuation of warrants, Series 1 nonconvertible preferred stock and stock-based awards; the accrual of research and 
development expenses, and the accounting for income taxes, including uncertain tax positions and the valuation of 
net deferred tax assets. Estimates are periodically reviewed in light of changes in circumstances, facts and 
experience. Actual results could differ from the Company’s estimates.

Cash Equivalents and Marketable Securities 

The Company considers all short-term, highly liquid investments with original maturities of ninety days or less at 
acquisition date to be cash equivalents. Marketable securities with original maturities of greater than ninety days and 
remaining maturities of less than one year from the balance sheet date are classified as short-term marketable 
securities. Marketable securities with remaining maturities of greater than one year from the balance sheet date are 
classified as long-term marketable securities. 

F-9

The Company classifies all of its marketable securities as available-for-sale. The Company continually evaluates the 
credit ratings of its investment portfolio and underlying securities. The Company invests in accordance with its 
investment policy and invests at the date of purchase in securities with a rating of A3 or higher and A- or higher 
according to Moody’s and S&P, respectively. The Company reports available-for-sale investments at fair value as of 
each balance sheet date and records any unrealized gains or losses as a component of stockholders’ equity. The cost 
of securities sold is determined on a specific identification basis, and realized gains and losses are included in other 
income (expense), net within the consolidated statements of operations. If any adjustment to fair value reflects a 
decline in the value of the investment, the Company considers available evidence to evaluate the extent to which the 
decline is “other than temporary” and reduces the investment to fair value through a charge to the consolidated 
statements of operations. There were no such adjustments necessary during the years ended September 30, 2018, 
2017, and 2016.

Restricted Cash 

As of September 30, 2018 and 2017 the Company had an outstanding letter of credit collateralized by a money 
market account of $608 to the benefit of the landlord of the Company’s current building lease. This amount was 
classified as long-term restricted cash as of September 30, 2018 and 2017.

Concentration of Credit Risk and of Significant Customers and Suppliers 

Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash, 
cash equivalents, marketable securities and accounts receivable. The Company has all cash and investment balances 
at one accredited financial institution, including cash in amounts that exceed federally insured limits. The Company 
does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial 
banking relationships. 

The Company has historically generated all of its revenue from its collaborative research and license agreements as 
well as a U.S. government contract (see Note 7). As of September 30, 2018 and 2017, accounts receivable consisted 
of amounts due from the Company’s principal collaborator (see Note 7). 

The Company is completely dependent on third-party manufacturers for product supply for preclinical and clinical 
research activities in its non-partnered programs. The Company relies and expects to continue to rely exclusively on 
several manufacturers to supply the Company with its requirements for the active pharmaceutical ingredients related 
to these programs. These research programs would be adversely affected by a significant interruption in the supply 
of its active pharmaceutical ingredients. 

Fair Value Measurements 

Certain assets and liabilities are carried at fair value under GAAP. Fair value is defined as the exchange price that 
would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous 
market for the asset or liability in an orderly transaction between market participants on the measurement date. 
Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use 
of unobservable inputs. A fair value hierarchy is based on three levels of inputs which are used to measure fair 
value, of which the first two levels are considered observable and the last is considered unobservable: 

(cid:129)

(cid:129)

(cid:129)

Level 1—Quoted prices in active markets for identical assets or liabilities. 

Level 2—Observable inputs (other than Level 1 quoted prices) such as quoted prices in active markets 
for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets 
or liabilities, or other inputs that are observable or can be corroborated by observable market data. 

Level 3—Unobservable inputs that are supported by little or no market activity and that are significant 
to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow 
methodologies and similar techniques. 

F-10

The Company’s instruments that are carried at fair value are cash equivalents, marketable securities and the warrant 
and Series 1 nonconvertible preferred stock liabilities. The carrying values of accounts receivable, accounts payable 
and accrued expenses approximate their fair value due to the short-term nature of these assets and liabilities. 

Property and Equipment 

Property and equipment are stated at cost less accumulated depreciation or amortization. Depreciation and 
amortization expense is recognized using the straight-line method over the following estimated useful lives: 

Laboratory and office equipment
Leasehold improvements
Purchased software
Computer equipment
Furniture

5 years
Shorter of life of lease or estimated useful life
3 years
3 years
7 years

Expenditures for repairs and maintenance of assets are charged to expense as incurred. Costs of major additions and 
betterments are capitalized and depreciated on a straight-line basis over their useful lives. Upon retirement or sale, 
the cost and related accumulated depreciation or amortization of assets disposed are removed from the accounts and 
any resulting gain or loss is included in income from operations in the consolidated statements of operations. 

Impairment of Long-Lived Assets 

The Company reviews long-lived assets, including property and equipment, for impairment whenever events or 
changes in business circumstances indicate that the carrying amount of the assets may not be fully recoverable. 
Factors that the Company considers in deciding when to perform an impairment review include significant 
underperformance of the business in relation to expectations, significant negative industry or economic trends, and 
significant changes or planned changes in the use of the assets. If an impairment review is performed to evaluate a 
long-lived asset for recoverability, the Company compares forecasts of undiscounted cash flows expected to result 
from the use and eventual disposition of the long-lived asset to its carrying value. An impairment loss would be 
recognized when estimated undiscounted future cash flows expected to result from the use of an asset are less than 
its carrying amount. The impairment loss would be based on the excess of the carrying value of the impaired asset 
over its fair value, determined based on discounted cash flows. To date, the Company has not recorded any 
impairment losses on long-lived assets. 

Revenue Recognition 

The Company’s revenue has been generated primarily through collaborative research and license agreements. The 
terms of these agreements contain multiple deliverables, which may include (i) licenses, (ii) research and 
development activities, and (iii) participation in joint research and development steering committees. The terms of 
these agreements may include nonrefundable upfront license fees, payments for research and development activities, 
payments based upon the achievement of certain milestones, and royalty payments based on product sales derived 
from the collaboration. In all instances, revenue is recognized only when the price is fixed or determinable, 
persuasive evidence of an arrangement exists, delivery has occurred or the services have been rendered, collectibility 
of the resulting receivable is reasonably assured, and the Company has fulfilled its performance obligations under 
the contract. 

The consideration received under multiple-element arrangements that is fixed or determinable is allocated among 
the separate units of accounting based on the relative selling prices of the separate units of accounting. The 
Company determines the selling price of a unit of accounting within each arrangement following the hierarchy of 
evidence prescribed by ASC 605-25. The selling prices of deliverables under the arrangement may be derived using 
third-party evidence (“TPE”) or a best estimate of selling price (“BESP”), if vendor-specific objective evidence 
(“VSOE”) is not available. The objective of BESP is to determine the price at which the Company would transact a 
sale if the element within the license agreement was sold on a standalone basis. Establishing BESP involves 
management’s judgment and considers multiple factors, including market conditions and company-specific factors 
including those factors contemplated in negotiating the agreements as well as internally developed models that 
include assumptions related to market opportunity, discounted cash flows, estimated development costs, probability 

F-11

of success, and the time needed to commercialize a product candidate pursuant to the license. Deliverables under a 
multiple-element arrangement are separated into multiple units if (i) the delivered item has value to the customer on 
a standalone basis, and (ii) if the arrangement includes a general right of return relative to the delivered item, 
delivery or performance of the undelivered item is considered probable and substantially within the control of the 
Company. The arrangement consideration that is fixed or determinable at the inception of the arrangement is 
allocated to the separate units of accounting based on their relative selling prices derived using TPE or BESP. The 
appropriate revenue recognition model is applied to each element, and revenue is accordingly recognized as each 
element is delivered. The Company may exercise significant judgment in determining whether a deliverable is a 
separate unit of accounting. 

In determining the separate units of accounting, the Company evaluates whether the license has standalone value to 
the collaborator based on consideration of the relevant facts and circumstances for each arrangement. Factors 
considered in this determination include the research and development capabilities of the collaborator and the 
availability of relevant research expertise in the marketplace. In addition, the Company considers whether or not 
(i) the collaborator can use the license for its intended purpose without the receipt of the remaining deliverables, 
(ii) the value of the license is dependent on the undelivered items, and (iii) the collaborator or other vendors can 
provide the undelivered items. 

For all periods presented, whenever the Company determines that an element is delivered over a period of time, 
revenue is recognized using either a proportional performance model or a straight-line model over the period of 
performance, which is typically the research and development term. Full-time equivalents (“FTEs”) are typically 
used as the measure of performance. At each reporting period, the Company reassesses its cumulative measure of 
performance and makes appropriate adjustments, if necessary. The Company recognizes revenue using the 
proportional performance model whenever the Company can make reasonably reliable estimates of the level of 
effort required to complete its performance obligations under an arrangement. Revenue recognized under the 
proportional performance model at each reporting period is determined by multiplying the total expected payments 
under the contract (excluding royalties and payments contingent upon achievement of milestones) by the ratio of the 
level of effort incurred to date to the estimated total level of effort required to complete the performance obligations 
under the arrangement. Revenue is limited to the lesser of the cumulative amount of payments received or the 
cumulative amount of revenue earned, as determined using the proportional performance model as of each reporting 
period. Alternatively, if the Company cannot make reasonably reliable estimates of the level of effort required to 
complete its performance obligations under an arrangement, then revenue under the arrangement is recognized on a 
straight-line basis over the period expected to complete the Company’s performance obligations. If and when a 
contingent milestone payment is earned, the additional consideration to be received is allocated to the separate units 
of accounting in the arrangement based on their relative selling prices at the inception of the arrangement. Revenue 
is limited to the lesser of the cumulative amount of payments received or the cumulative amount of revenue earned, 
as determined on a straight-line basis as of the period end date. If the Company cannot reasonably estimate when its 
performance obligation period ends, then revenue is deferred until the Company can reasonably estimate when the 
performance obligation period ends. 

Royalty revenue is recognized based on contractual terms when reported sales are reliably measurable and 
collectibility is reasonably assured, provided that there are no performance obligations remaining. 

During the year ended September 30, 2016, the Company also generated revenue from a government contract, under 
which the Company was reimbursed for certain allowable costs for the funded project. Revenue from the 
government contract was recognized when the related service was performed. The related costs incurred by the 
Company under the government contract were included in research and development expenses in the consolidated 
statements of operations. 

Amounts received prior to satisfying all revenue recognition criteria are recorded as deferred revenue in the 
accompanying consolidated balance sheets. Amounts not expected to be recognized as revenue within the next 
twelve months of the consolidated balance sheet date are classified as long-term deferred revenue. 

In the event that a collaborative research and license agreement is terminated and the Company then has no further 
performance obligations, the Company recognizes as revenue any amounts that had not previously been recorded as 
revenue but were classified as deferred revenue at the date of such termination. 

F-12

Research and Development Costs 

Research and development costs are expensed as incurred. Included in research and development costs are wages, 
stock-based compensation and benefits of employees, third-party license fees and other operational costs related to 
the Company’s research and development activities, including facility-related expenses and external costs of outside 
contractors engaged to conduct both preclinical and clinical studies and manufacture quantities of product for 
preclinical and clinical studies. The Company also includes in research and development expense the costs to 
complete the Company’s obligations under research collaborations. 

Upfront payments and milestone payments made for the licensing of technology are expensed as research and 
development in the period in which they are incurred. Advance payments for goods or services to be received in the 
future for use in research and development activities are recorded as prepaid expenses. The prepaid amounts are 
expensed as the related goods are delivered or the services are performed.

Research and Manufacturing Contract Accruals

The Company has entered into various research and development and manufacturing contracts. These agreements 
are generally cancelable, and related payments are recorded as the corresponding expenses are incurred. The 
Company records accruals for estimated ongoing costs. When evaluating the adequacy of the accrued liabilities, the 
Company analyzes progress of the research and development and manufacturing activities, including the phase or 
completion of events, invoices received and contracted costs. Significant judgments and estimates are made in 
determining the accrued balances at the end of any reporting period. Actual results could differ from the Company's 
estimates. The Company's historical accrual estimates have not been materially different from the actual costs.

Patent Costs 

All patent-related costs incurred in connection with filing and prosecuting patent applications are recorded as 
general and administrative expenses as incurred. 

Stock-Based Compensation 

The Company measures all stock options and other stock-based awards granted to employees at fair value on the 
date of grant. The Company uses the Black-Scholes option-pricing model in the valuation of its stock options. The 
fair value of performance-based awards and restricted stock units is based on intrinsic value of the stock on the date 
of grant. The Company uses the Monte-Carlo model in order to calculate the fair value of the market-based awards. 
The fair value of options is recognized as stock-based compensation expense over the requisite service period, which 
is generally the vesting period of the respective award. Commencing with the adoption of ASU No. 2016-09 on 
October 1, 2017, the Company accounts for stock-based compensation expense related to forfeitures as the 
forfeitures occur.  The straight-line method of expense recognition is applied to all awards with service-based and 
market-based conditions. The Company records stock-based compensation expense related to performance-based 
awards when the performance-based targets are probable of being achieved. The Company classifies stock-based 
compensation expense in the consolidated statements of operations in the same manner in which the award 
recipient’s payroll costs are classified. 

Income Taxes 

The Company accounts for income taxes using the asset and liability method, which requires the recognition of 
deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the 
financial statements or in the Company’s tax returns. Deferred taxes are determined based on the difference between 
the financial reporting and tax basis of assets and liabilities using enacted tax rates in effect in the years in which the 
differences are expected to reverse. Changes in deferred tax assets and liabilities are recorded in the provision for 
income taxes. The Company assesses the likelihood that its deferred tax assets will be recovered from future taxable 
income and, to the extent it believes based upon the weight of available evidence, that it is more likely than not that 
all or a portion of deferred tax assets will not be realized, a valuation allowance is established through a charge to 
income tax expense. Potential for recovery of deferred tax assets is evaluated by estimating the future taxable profits 
expected and considering prudent and feasible tax planning strategies. 

F-13

Uncertain tax positions represent tax positions for which reserves have been established. The Company accounts for 
uncertainty in income taxes recognized in the consolidated financial statements by applying a two-step process to 
determine the amount to be recognized. First, the tax position must be evaluated to determine the likelihood that it 
will be sustained upon external examination by the taxing authorities. If the tax position is deemed more likely than 
not to be sustained, the tax position is then assessed to determine the amount of benefit to be recognized in the 
financial statements. The amount that may be recognized is the largest amount that has a greater than 50% likelihood 
of being realized upon ultimate settlement. Income tax expense includes the effects of any resulting tax reserves, or 
unrecognized tax benefits, that are considered appropriate as well as the related net interest and penalties. 

Net Income per Share 

Basic net income per common share is computed by dividing the net income by the weighted average number of 
shares of common stock outstanding for the period. Diluted net income per common share is computed by dividing 
net income by the weighted average number of common shares outstanding for the period, including potential 
dilutive common shares assuming the dilutive effect of outstanding stock options and unvested restricted stock units. 
Market-based awards are included in diluted net income per common share to the extent they would have vested if 
the period end date was the market criteria measurement date. 

Segment Data 

The Company manages its operations as a single segment for the purposes of assessing performance and making 
operating decisions. The Company is a biotechnology company focused on discovering and developing small 
molecule drugs for the treatment of viral infections and liver diseases. Revenue is generated exclusively from 
transactions occurring with partners located in the United States and all assets are held in the United States. 

Comprehensive Income 

Comprehensive income includes net income as well as other changes in stockholders’ equity that result from 
transactions and economic events other than those with stockholders. The Company’s only element of other 
comprehensive income is unrealized gains and losses on available-for-sale marketable securities.

Going Concern

In August 2014, the Financial Accounting Standards Board (the “FASB”) issued ASU 2014-15, Presentation of 
Financial Statements - Going Concern (Subtopic 205-40) (“ASU 2014-15”). The Company adopted this standard as 
of September 30, 2017. The standard requires the Company to assess its ability to continue as a going concern one 
year beyond the date of filing and, in certain circumstances, provide additional footnote disclosures. Based on a 
detailed cash forecast incorporating current research and development activities and related spending plans, the 
Company believes that current cash, cash equivalents and marketable securities on hand at September 30, 2018 
should be sufficient to fund operations for the foreseeable future, including at least the next twelve months beyond 
the date of issuance of these financial statements. The amount of capital available will depend on the Company’s 
management of its existing cash, cash equivalents and marketable securities, as well as the level of future royalties 
the Company earns under its agreement with AbbVie. If the Company should require financing beyond these 
resources to fund its research and development efforts, it may not be able to obtain financing on acceptable terms, or 
at all.  

F-14

Recently Issued Accounting Pronouncements 

In March 2016, the FASB issued ASU No. 2016-09, Improvements to Employee Share-Based Payment 
Accounting (“ASU 2016-09”), which intends to simplify several aspects of accounting for share-based payment 
transactions, including the income tax consequences, classification of awards as either equity or liabilities, a choice 
to recognize gross stock compensation expense with actual forfeitures recognized as they occur, as well as certain 
classifications on the statement of cash flows. This amendment was effective for the Company in the fiscal year 
beginning October 1, 2017. As a result of the adoption, the Company changed its forfeiture rate policy to recognize 
forfeitures as they occur. Upon adoption, the cumulative impact of this accounting policy change on retained 
earnings, additional paid-in capital and deferred tax assets in the consolidated balance sheet was not material. In 
addition, the consolidated statements of cash flows now presents excess tax benefits as part of cash flows from 
operating activities. The Company elected to adopt this change on a prospective basis and, therefore, excess tax 
benefits from prior periods in the consolidated statements of cash flow were not restated. The adoption of the 
standard is also expected to create variability in the consolidated statements of operations in years in which the 
Company is expected to have taxable income, as the tax consequences of settled share-based payments will be 
recognized in income tax expense when share-based payment awards are settled.

In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606) (“ASU 
2014-09”) which supersedes all existing revenue recognition requirements, including most industry-specific 
guidance. The new standard requires a company to recognize revenue when it transfers goods or services to 
customers in an amount that reflects the consideration that the company expects to receive for those goods or 
services. The FASB has continued to issue accounting standards updates to clarify and provide implementation 
guidance related to Revenue from Contracts with Customers, including ASU 2016-08, Revenue from Contract with 
Customers: Principal versus Agent Considerations, ASU 2016-10, Revenue from Contracts with Customers: 
Identifying Performance Obligations and Licensing, and ASU 2016-12, Revenue from Contracts with Customers: 
Narrow-Scope Improvements and Practical Expedients. These amendments address a number of areas, including an 
entity’s identification of its performance obligations in a contract, collectibility, non-cash consideration, presentation 
of sales tax and an entity’s evaluation of the nature of its promise to grant a license of intellectual property and 
whether or not that revenue is recognized over time or at a point in time. The new guidance must be adopted using 
either a modified retrospective approach or a full retrospective approach for all periods presented. Under the 
modified retrospective method, the cumulative effect of applying the new standard would be recognized at the 
adoption date in retained earnings on the consolidated balance sheet. Under the full retrospective approach, the new 
standard would be applied to each prior reporting period presented. These new standards will be effective for the 
Company beginning October 1, 2018. The Company will adopt the standard under the modified retrospective 
method, the impact of which is not expected to have a material impact on the Company’s consolidated financial 
statements as the AbbVie Agreement is the only revenue-generating arrangement outstanding and all performance 
obligations under the agreement have been completed by the end of fiscal 2011. The adoption of ASU 2014-09 did 
not have an impact on the Company’s accounting for contingent milestone or royalty payments. All contingent 
milestone payments earned since fiscal 2011 have been recognized as revenue when the associated milestone was 
achieved by AbbVie. The Company is currently earning annually tiered per-product royalties on the portion of 
AbbVie’s net sales of its HCV regimens allocable to the protease inhibitor product in the regimen.

In November 2016, the FASB issued ASU No. 2016-18, Statement of Cash Flows (Topic 230): Restricted 
Cash (“ASU 2016-18”) that changes the presentation of restricted cash and cash equivalents on the statement of cash 
flows. Restricted cash and restricted cash equivalents will be included with cash and cash equivalents when 
reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. This 
amendment is effective for the Company in the fiscal year beginning October 1, 2018, but early adoption is 
permissible. Upon adoption, the Company will adjust the presentation of the statement of cash flows to include 
restricted cash related to an outstanding letter of credit collateralized by a money market fund of $608 so that it is 
included in the balances of cash and cash equivalents. 

In May 2017, the FASB issued ASU No. 2017-09, Compensation—Stock Compensation (Topic 718) (“ASU 2017-
09”) which provides updated guidance about changes to the terms or conditions of a share-based payment award that 
requires companies to apply modification accounting under Topic 718. This amendment is effective for the 
Company in the fiscal year beginning October 1, 2018, but early adoption is permissible. The Company does not 
expect the adoption of ASU 2017-09 to have a material impact on its consolidated financial statements.

F-15

In February 2016, the FASB issued ASU No. 2016-02, Leases (“ASU 2016-02”), which will replace the existing 
guidance in ASC 840, “Leases.” The updated standard aims to increase transparency and comparability among 
organizations by requiring lessees to recognize leased assets and leased liabilities on the consolidated balance sheets 
and requiring disclosure of key information about leasing arrangements. This amendment is effective for the 
Company in the fiscal year beginning October 1, 2019, but early adoption is permissible. The Company is currently 
evaluating the potential impact that ASU 2016-02 may have on its financial position and results of operations.

In March 2017, the FASB issued ASU No. 2017-08, Receivables—Nonrefundable Fees and Other Costs (Subtopic 
310-20): Premium Amortization on Purchased Callable Debt Securities (“ASU 2017-08”) which requires 
companies to amend the amortization period for premiums on debt securities with explicit call features to be the 
earliest call date rather than through the contractual life of the debt instrument. This amendment aims to more 
closely align the recognition of interest income with the manner in which market participants price such instruments. 
This amendment is effective for the Company in the fiscal year beginning October 1, 2019, but early adoption is 
permissible. The Company is currently evaluating the potential impact that ASU 2017-08 may have on its financial 
position and results of operations.

In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments—Credit Losses (“ASU 2016-13”), which 
introduces a new methodology for accounting for credit losses on financial instruments, including available-for-sale 
debt securities. The guidance establishes a new “expected loss model” that requires entities to estimate current 
expected credit losses on financial instruments by using all practical and relevant information. Any expected credit 
losses are to be reflected as allowances rather than reductions in the amortized cost of available-for-sale debt 
securities. This amendment is effective for the Company in the fiscal year beginning October 1, 2020. The Company 
is currently evaluating the potential impact that ASU 2016-13 may have on its financial position and results of 
operations.

Other accounting standards that have been issued or proposed by the FASB or other standards-setting bodies that do 
not require adoption until a future date are not expected to have a material impact on the Company’s consolidated 
financial statements upon adoption.

3. Fair Value of Financial Assets and Liabilities 

The following tables present information about the Company’s financial assets and liabilities that were subject to 
fair value measurement on a recurring basis as of September 30, 2018 and 2017 and indicate the fair value hierarchy 
of the valuation inputs utilized to determine such fair value: 

  Fair Value Measurements at September 30, 2018 Using:

Level 1

Level 2

Level 3

Total

(in thousands)

Assets:
Cash equivalents:

Money market funds
Commercial paper
Corporate bonds
Marketable securities:
U.S. Treasury notes
Commercial paper
Corporate bonds

Liabilities:
Series 1 nonconvertible preferred stock

  $

51,025    $
—     
—     

—    $
6,987     
3,998     

42,703     

—     
—      113,885     
—      104,629     
93,728    $ 229,499    $

—    $
—     
—     

51,025 
6,987 
3,998 

—     
42,703 
—      113,885 
—      104,629 
—    $ 323,227 

—     
—    $

—     
—    $

1,628     
1,628    $

1,628 
1,628  

  $

  $

F-16

 
 
 
   
   
   
 
 
 
 
   
      
      
      
  
   
      
      
      
  
   
   
   
      
      
      
  
   
   
   
 
   
      
      
      
  
   
 
Assets:
Cash equivalents:

Money market funds
Commercial paper
Corporate bonds
Marketable securities:
U.S. Treasury notes
Corporate bonds
Commercial paper
U.S. Agency bonds

Liabilities:
Warrant liability
Series 1 nonconvertible preferred stock

  $

  $

  $

  Fair Value Measurements at September 30, 2017 Using:

Level 1

Level 2

Level 3

Total

(in thousands)

  $

19,863    $
—     
—     

—    $
29,756     
3,000     

60,843     

—     
—      150,731     
—     
12,458     
—     
4,000     
80,706    $ 199,945    $

—    $
—     
—     

19,863 
29,756 
3,000 

—     
60,843 
—      150,731 
—     
12,458 
—     
4,000 
—    $ 280,651 

—    $
—     
—    $

—    $
—     
—    $

807    $
762     
1,569    $

807 
762 
1,569  

Cash equivalents at September 30, 2018 and 2017 consist of money market funds, corporate bonds and commercial 
paper which are readily convertible to cash and with less than 90 days until maturity. 

During the years ended September 30, 2018, 2017, and 2016, there were no transfers between Level 1, Level 2 and 
Level 3. 

As of September 30, 2017, the Company’s warrant liability was comprised of the value of warrants for the purchase 
of its Series 1 nonconvertible preferred stock. These warrants were financial instruments that might have required a 
transfer of assets because of the liquidation features in the contract and were therefore recorded as liabilities and 
measured at fair value. These warrants expired on October 4, 2017, and are therefore no longer outstanding. The 
outstanding shares of Series 1 nonconvertible preferred stock as of September 30, 2018 and 2017 were also 
measured at fair value. The fair values of both of these instruments were based on significant inputs not observable 
in the market, which represented a Level 3 measurement within the fair value hierarchy. The Company utilized a 
probability-weighted valuation model which takes into consideration various outcomes that may require the 
Company to transfer assets upon exercise. Changes in the fair values of the warrant liability and Series 1 
nonconvertible preferred stock are recognized in other income (expense) in the consolidated statements of 
operations. 

The recurring Level 3 fair value measurements of the Company’s warrant liability and Series 1 nonconvertible 
preferred stock using probability-weighted discounted cash flow include the following significant unobservable 
inputs: 

Unobservable Input

Probabilities of payout

Discount rate

  Range (Weighted Average)  
September 30,

2018

2017

  0%-70%    0%-65%  
5.25%  

6.25%   

F-17

 
 
 
   
   
   
 
 
 
 
   
 
     
 
     
 
     
 
 
   
 
     
 
     
 
     
 
 
   
   
   
 
     
 
     
 
     
 
 
   
   
   
   
 
   
     
     
     
  
   
 
 
 
 
 
   
 
 
The following table provides a rollforward of the aggregate fair values of the Company’s warrants for the purchase 
of Series 1 nonconvertible preferred stock and the outstanding Series 1 nonconvertible preferred stock for which fair 
value is determined by Level 3 inputs:

Series 1
Nonconvertible
Preferred
Stock

Warrant 
Liability    

Balance, September 30, 2015
Decrease in fair value
Balance, September 30, 2016

Warrants exercised
Increase in fair value

Balance, September 30, 2017

Warrants exercised
Warrants expired
Increase in fair value

Balance, September 30, 2018

(in thousands)
$

$ 1,276   
(25) 
  1,251   
(549) 
105   
807   
(766) 
(41)
— 
—   

$

$

163 
(4)
159 
549 
54 
762 
766 
— 
100 
1,628  

4. Marketable Securities 

As of September 30, 2018 and 2017, the fair value of available-for-sale marketable securities, by type of security, 
was as follows: 

Commercial paper
Corporate bonds
U.S. Treasury notes

Corporate bonds
U.S. Treasury notes
Commercial paper
U.S. Agency bonds

September 30, 2018
Gross
Gross
Unrealized
Unrealized
Losses
Gains

Amortized
Cost

    Fair Value  

 $ 113,885   $
    105,105    
    42,801    
  $ 261,791   $

(in thousands)
—   $
1    
—    
1   $

—   $ 113,885 
(477)    104,629 
(98)    42,703 
(575)  $ 261,217  

September 30, 2017
Gross
Gross
Unrealized
Unrealized
Losses
Gains

Amortized
Cost

    Fair Value  

 $ 150,841   $
   60,908    
   12,458    
4,004    
  $ 228,211   $

(in thousands)
9   $
—    
—    
—    
9   $

(119)  $ 150,731 
(65)    60,843 
—     12,458 
4,000 
(4)   
(188)  $ 228,032  

As of September 30, 2018 and 2017, marketable securities consisted of investments that mature within one year, 
with the exception of certain corporate bonds and U.S. Treasury notes, which have maturities between one and three 
years and an aggregate fair value of $16,389 and $70,038, respectively. 

F-18

 
 
 
 
 
 
 
 
 
 
 
 
  
 
  
 
 
 
 
 
 
 
  
  
  
  
 
 
 
 
 
 
   
   
 
 
 
 
 
 
 
 
   
   
 
 
 
   
 
5. Property and Equipment, Net 

Property and equipment, net consisted of the following as of September 30, 2018 and 2017: 

Laboratory and office equipment
Leasehold improvements
Purchased software
Furniture
Computer equipment
Construction in progress

Less: Accumulated depreciation and amortization

September 30,

2018

2017

(in thousands)

  $

   $

 $

11,110 
3,739 
1,039 
630 
331 
617 
17,466 
(9,092)   
 $
8,374 

9,521 
3,717 
775 
595 
245 
250 
15,103 
(7,054)
8,049  

Depreciation and amortization expense for property and equipment, including assets acquired under capital leases, 
was $2,518, $2,137 and $1,661 for the years ended September 30, 2018, 2017, and 2016, respectively. 

6. Accrued Expenses and Other Current Liabilities and Other Long-Term Liabilities 

Accrued expenses and other current liabilities and other long-term liabilities consisted of the following as of 
September 30, 2018 and 2017: 

Accrued expenses and other current liabilities:
Accrued preclinical and clinical expenses
Accrued payroll and related expenses
Accrued vendor manufacturing
Accrued professional fees
Accrued other

Other long-term liabilities:
Uncertain tax positions
Accrued rent expense
Capital lease obligation
Asset retirement obligation

7. Collaboration Agreements 

AbbVie Collaboration 

September 30,

2018

2017

(in thousands)
3,617   $
3,274    
1,901    
507    
593    
9,892   $

1,792   $
593    
293    
217    
2,895   $

3,156 
2,829 
1,130 
456 
399 
7,970 

1,175 
676 
379 
180 
2,410  

  $

  $

  $

  $

On November 27, 2006, the Company entered into a Collaborative Development and License Agreement (the 
“AbbVie Agreement”) with Abbott Laboratories to identify, develop and commercialize HCV NS3 and NS3/4A 
protease inhibitor compounds, including paritaprevir and glecaprevir. The agreement was assigned by Abbott to 
AbbVie Inc. on January 1, 2013 in connection with Abbott’s transfer of its research-based pharmaceuticals business 
to AbbVie. 

F-19

 
 
 
 
 
   
 
 
 
 
   
  
   
  
   
  
   
  
   
  
 
   
  
   
 
 
 
 
   
 
 
 
   
   
   
   
 
 
   
     
  
   
     
  
   
   
   
 
Under the terms of the AbbVie Agreement, as amended, AbbVie paid the Company upfront license payments and 
FTE reimbursements to fund research activities. The Company is also eligible to receive milestone payments for the 
successful development by AbbVie of one or more HCV compounds, as well as annually tiered, per-product 
royalties on the portion of AbbVie’s net sales of its HCV treatment regimens allocated to the protease inhibitor 
product. 

The Company determined that the deliverables under the AbbVie Agreement included (i) the non-exclusive, royalty-
free, worldwide research license and the exclusive, royalty-bearing development and commercialization license, 
(ii) the research services, and (iii) a commitment to participate on a steering committee, all of which were to be 
delivered over a three-year period. The Company concluded that the license did not have standalone value as it was 
dependent, in part, upon the Company’s continuing involvement in the HCV protease inhibitor research and its 
involvement in the joint steering committee. Additionally, the undelivered items, including the Company’s 
participation in the joint steering committee, which was considered participatory due to its decision making 
responsibilities, and the research services, did not have VSOE or VOE of fair value. Therefore, the license, the 
research services, and the joint steering committee participation were treated as a single unit of accounting. 
Accordingly, all amounts received were deferred, and revenue was recognized using the proportional performance 
model over the period during which the Company performed research services in connection with the AbbVie 
Agreement, as amended. 

Subsequent to the research and evaluation period, which ended in June 2011, all decisions related to the 
development, commercialization and marketing have been made by AbbVie. The Company has the right to continue 
to attend the joint steering committee meetings to monitor the development and marketing plans; however, the 
Company has no decision-making rights. As such, the joint steering committee commitment became protective in 
nature as of June 16, 2011. 

During the years ended September 30, 2018, 2017, and 2016, the Company received $15,000, $65,000, and $30,000, 
respectively, in milestone payments under the AbbVie Agreement as a result of AbbVie’s commercialization 
regulatory approvals. From commencement of the collaboration through September 30, 2018 the Company has 
received an upfront license payment, research funding, milestone payments, and preferred stock financing totaling 
$396,000 under the AbbVie agreement. Since the Company completed all its performance obligations under the 
AbbVie Agreement by the end of fiscal 2011, any milestone payments earned since then have been recognized as 
revenue when the associated milestone was achieved by AbbVie. 

The Company is also receiving annually tiered royalties per Company protease product ranging from ten percent up 
to twenty percent, or on a blended basis from the low double digits up to the high teens, on the portion of AbbVie’s 
calendar year net sales of each HCV regimen that is allocated to the protease inhibitor product in the regimen. 
Beginning with each January 1, the cumulative net sales of a given royalty-bearing protease inhibitor product start at 
zero for purposes of calculating the tiered royalties on a product-by-product basis. The following table details the 
royalty tiers associated with cumulative calendar year net sales allocated to each royalty-bearing product as provided 
in the AbbVie Agreement:

Calendar Year Net Sales

Royalty Tier

(in thousands)

up to $500,000

from $500,000 up to $750,000

from $750,000 up to $1,000,000

from $1,000,000 up to $2,500,000

greater than or equal to $2,500,000

(%)

10%

12%

14%

17%

20%

Royalties owed to the Company under the agreement can be reduced by AbbVie in certain circumstances, including 
(i) if AbbVie exercises its right to license or otherwise acquire rights to intellectual property controlled by a third 
party where a product could not be legally developed or commercialized in a country without the third-party 
intellectual property right, (ii) where a product developed under the collaboration agreement is sold in a country and 
not covered by a valid patent claim in such country, and (iii) where sales of a generic product are equal to at least a 
specified percentage of AbbVie’s market share of its product in a country. 

F-20

 
 
 
 
 
 
 
 
 
 
 
 
 
 
AbbVie’s obligation to pay royalties on a product developed under the agreement expires on a country-by-country 
basis upon the later of (i) the date of expiration of the last of the licensed patents with a valid claim covering the 
product in the applicable country, or (ii) ten years after the first commercial sale of the product in the applicable 
country. 

Subject to certain exceptions, a party’s rights and obligations under the agreement continue until (i) such time as 
AbbVie is no longer developing a product candidate or (ii) if, as of the time AbbVie is no longer developing any 
product candidates, AbbVie is commercializing any other protease inhibitor product, such time as all royalty terms 
for all covered products have ended. Accordingly, the final expiration date of the agreement is currently 
indeterminable. 

Either party may terminate the agreement for cause in the event of a material breach, subject to prior notice and the 
opportunity to cure, or in the event of the other party’s bankruptcy. Additionally, AbbVie may terminate the 
agreement for any reason upon specified prior notice. 

If the Company terminates the agreement for cause or AbbVie terminates without cause, any licenses and other 
rights granted to AbbVie will terminate and AbbVie will be deemed to have granted the Company (i) a non-
exclusive, perpetual, fully-paid, worldwide, royalty-free license, with the right to sublicense, under AbbVie’s 
intellectual property used in any product candidate, and (ii) an exclusive (even as to AbbVie), perpetual, fully-paid, 
worldwide, royalty-free license, with the right to sublicense, under AbbVie’s interest in any joint intellectual 
property rights to develop product candidates resulting from covered compounds and to commercialize any products 
derived from such compounds. Upon the Company’s request, AbbVie will also transfer to the Company all right, 
title and interest in any related product trademarks, regulatory filings and clinical trials. 

If AbbVie terminates the agreement for the Company’s uncured breach, the milestone and royalty payments payable 
by AbbVie may be reduced, the licenses granted to AbbVie will remain in place, the Company will be deemed to 
have granted AbbVie an exclusive license under the Company’s interest in joint intellectual property, AbbVie will 
continue to have the right to commercialize any covered products, and all rights and licenses granted to the 
Company by AbbVie will terminate. 

NIAID Contract 

On September 30, 2011, the Company entered into a contract with the National Institute of Allergy and Infectious 
Diseases (“NIAID”), a division of the National Institutes of Health (“NIH”), providing development funding to the 
Company for the preclinical and clinical development of a bridged bicyclic antibiotic. The contract was completed 
in August 2015 upon the Company’s delivery of the study report for the Phase 1 clinical study. 

The Company recognized revenue under this contract as development services were performed in accordance with 
the funding agreement. During the year ended September 30, 2016, the Company recognized revenue of $576 under 
this contract. The Company received aggregate payments of $20,637 under the NIAID contract from its 
commencement through January 31, 2016. 

8. Stockholders’ Equity 
The Company is authorized to issue 100,000 shares of common stock at a par value of $0.01. Each share of common 
stock entitles the holder to one vote on all matters submitted to a vote of the Company’s stockholders. Common 
stockholders are entitled to receive such dividends as may be declared by the board of directors, if any. 

9. Series 1 Nonconvertible Preferred Stock and Warrants 

The Company’s Certificate of Incorporation authorizes the issuance of up to 2,000 shares of Series 1 nonconvertible 
preferred stock at a par value of $0.01 per share. Holders of Series 1 nonconvertible preferred stock are not entitled 
to receive dividends. In the event of any liquidation, deemed liquidation, dissolution or winding up of the Company, 
the Series 1 nonconvertible preferred stockholders are entitled to receive in preference to all other stockholders, an 
amount equal to $1.00 per share, adjusted for any stock dividends, stock splits or reclassifications. Series 1 

F-21

nonconvertible preferred stockholders will not be entitled to vote unless required by the Company pursuant to the 
laws of the State of Delaware. The Company may redeem the Series 1 nonconvertible preferred stock with the 
approval of the holders of a majority of the outstanding shares of Series 1 nonconvertible preferred stock at a 
redemption price of $1.00 per share. The Company must redeem the stock within 60 days of such election. Shares 
that are redeemed will be retired or canceled and not reissued by the Company. As these shares qualify as a 
derivative, they are classified as a liability on the Company’s consolidated balance sheet.

In October and November 2010, a total of 2,000 warrants to purchase Series 1 nonconvertible preferred stock were 
issued. The warrants had an expiration date of October 4, 2017. As these warrants were free-standing financial 
instruments that might have required the Company to transfer assets upon exercise, up to a maximum of $2,000, 
these warrants were classified as liabilities on the Company’s consolidated balance sheet as of September 30, 2017. 

The following table summarizes the activity of the warrants to purchase Series 1 nonconvertible preferred stock: 

Outstanding, as of September 30, 2015

Granted
Expired
Exercised

Outstanding, as of September 30, 2016

Granted
Expired
Exercised

Outstanding, as of September 30, 2017

Granted
Expired
Exercised

Outstanding, as of September 30, 2018

Weighted
Average
Exercise
Price

Series 1
Nonconvertible
Preferred
Stock Warrant
s
Exercisable
(in thousands, except per share 
data)
1,775    $
—     
—     
—     
1,775    $
—     
—     
(745)   
1,030    $
—     
(52)   
(978)   
—     

0.01 
— 
— 
— 
0.01 
— 
— 
0.01 
0.01 
— 
0.01 
0.01 

For the years ended September 30, 2018, 2017, and 2016, the remeasurement of the warrants and Series 1 
nonconvertible preferred stock resulted in other income (expense) recorded in the consolidated statements of 
operations of ($59), $(159), and $29, respectively. As of September 30, 2018 and 2017, the total fair value of the 
Series 1 nonconvertible preferred stock was $1,628 and $762, respectively. 

During the year ended September 30, 2018, warrants to purchase a total of 978 shares of Series 1 nonconvertible 
preferred stock were exercised prior to warrant expiration, resulting in the issuance of 970 shares of Series 1 
nonconvertible preferred stock. On October 4, 2017, a total of 52 outstanding warrants expired unexercised. The 
liability associated with these expired warrants was reversed, resulting in other income of $41 during the year ended 
September 30, 2018.

10. Stock-Based Awards 

The Company’s 2012 Equity Incentive Plan (the “2012 Plan”) permits the Company to sell or issue awards of 
common stock or restricted common stock or to grant awards of incentive stock options or nonqualified stock 
options for the purchase of common stock, restricted stock units, performance units, stock appreciation rights or 
other cash incentive awards, to employees, members of the board of directors and consultants of the Company. The 
number of shares of common stock that may be issued under the 2012 Plan is subject to increase by the number of 
shares forfeited under any options forfeited and not exercised under the 2012 Plan or a predecessor plan, known as 

F-22

 
 
 
 
 
 
 
   
   
   
   
   
   
   
   
   
   
   
   
   
  
 
     
       
 
the 1995 Equity Incentive Plan, as well as by the number of shares added on the first day of each fiscal year, which 
is the lowest amount among the following: (i) 3% of the Company’s outstanding shares of common stock as of that 
date, (ii) 2,088 shares of common stock, or (iii) an amount determined by the Compensation Committee of the Board 
of Directors. On October 1, 2018, the number of shares of common stock that might be issued under the 2012 Plan 
was increased by 583 shares. As of September 30, 2018, 251 shares remained available for future award. 

The 2012 Plan replaces and is the successor to the 1995 Equity Incentive Plan (the “1995 Plan”). The 1995 Plan 
provided for the Company to sell or issue awards of common stock or restricted common stock, or to grant awards 
of incentive stock options or nonqualified stock options for the purchase of common stock, to employees, members 
of the board of directors and consultants of the Company. Sales, issuances or grants of shares entitle the holder to 
purchase common stock from the Company, for a specified exercise price, during a period specified by the 
applicable equity award agreement. Upon the closing of the Company’s initial public offering, all remaining shares 
reserved for issuance under the 1995 Plan were transferred to the 2012 Plan and no further awards were or will be 
made under the 1995 Plan. 

Under the Company’s Employee Stock Purchase Plan (“ESPP”) a total of 186 shares of common stock are reserved 
for issuance. As of September 30, 2018, the Company had not commenced any offering under the ESPP and no plan 
shares have been issued. 

The Company applies the fair value recognition provisions for all stock-based awards granted or modified. In the 
case of service-based awards, the compensation cost is recorded over the requisite service period of the award on the 
straight-line method based on the grant-date fair value. The requisite service period for service-based option awards 
is generally four years. Options granted under the 2012 Plan to employees generally vest over four years and to non-
employee directors over one year, and expire after ten years. 

Stock Option Valuation 

The fair value of each stock option award is determined on the date of grant using the Black-Scholes option-pricing 
model. The Company estimates expected volatility based on a combination of the Company’s historical stock 
volatility since its March 2013 IPO and the historical volatility of publicly traded peer companies. The Company 
expects to continue to do so until 2019, at which time the Company will have adequate historical data regarding the 
volatility of the Company’s traded stock price following our March 2013 IPO. The expected term of the Company’s 
options has been determined utilizing the “simplified” method for awards that qualify as “plain-vanilla” options. The 
risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the 
award for time periods approximately equal to the expected term of the award. The expected dividend yield is zero 
on the fact that the Company has never paid cash dividends and does not expect to pay any cash dividends in the 
foreseeable future. As required by the 1995 Plan and the 2012 Plan, the exercise price for awards granted is not to be 
less than the fair value of common shares as estimated by the Company as of the date of grant. The relevant data 
used to determine the value of the stock option awards are as follows, presented on a weighted average basis: 

Years Ended September 30,
2017

2016

2018

Risk-free interest rate
Expected term (in years)
Expected volatility
Expected dividends

2.29%   
6.05 

57%   
0%   

1.97%   
6.05 

60%   
0%   

1.77%
6.1 
70%
0%

As discussed in Note 2, the Company adopted ASU 2016-09 during the year ended September 30, 2018. ASU 2016-
09 intends to simplify several aspects of accounting for share-based payment transactions, including the income tax 
consequences, classification of awards as either equity awards or liability awards, a choice to recognize gross stock 
compensation expense with actual forfeitures recognized as they occur, as well as certain classifications on the 
statement of cash flows. As a result of the adoption, the Company changed its forfeiture rate policy to recognize 
forfeitures as they occur. Upon adoption, the cumulative impact of this change in policy on retained earnings and 
deferred tax assets in the consolidated balance sheet was not material. In addition, the consolidated statements of 
cash flows presents excess tax benefits, if any, as part of cash flows from operating activities. The Company elected 

F-23

 
 
 
 
 
 
 
 
 
 
  
  
   
 
  
  
to adopt this change on a prospective basis and, therefore, excess tax benefits from prior periods in the statement of 
cash flow were not retroactively restated. The adoption of the standard is also expected to create variability in the 
consolidated statements of operations in years in which the Company is expected to have taxable income, as the tax 
consequences of settled share-based payments will be recognized in income tax expense when share-based payment 
awards are settled.

The following table summarizes stock option activity, including aggregate intrinsic value for the year ended 
September 30, 2018: 

Weighted
Average
Remaining
Contractual
Term in 
years

Weighted
Average
Exercise
Price

Shares
Issuable
Under
Options
(in 

thousands)      
2,298    $
606     
(229)   
(51)   
2,624    $

30.36     
57.96     
27.23     
48.74     
36.65     

Aggregate
Intrinsic
Value
(in 
thousands)  
37,821 

7.4    $

7.1    $ 129,115 

2,624    $
1,646    $

36.65     
31.84     

7.1    $ 129,115 
6.2    $
88,289  

Outstanding as of September 30, 2017

Granted
Exercised
Forfeited

Outstanding as of September 30, 2018
Options vested and expected to vest as of 
September 30, 2018
Options exercisable as of September 30, 2018

The aggregate intrinsic value of options is calculated as the difference between the exercise price of the options and 
the fair value of the Company’s common stock. The following tables summarize additional exercise and grant date 
information: 

2018

Years Ended September 30,
2017
(in thousands)

2016

Aggregate intrinsic value of stock options exercised
Proceeds to Company from stock options exercised

  $
 $

14,180    $
6,243    $

1,503    $
1,079    $

7,705 
1,026  

Weighted average grant date fair value of options granted 
(per share)

  $

31.84    $

17.52    $

19.12  

Years Ended September 30,

2018

2017

2016

Performance-Based Options 

In March 2013, the Company granted to certain executives 167 options that would vest upon the achievement of 
certain performance-based targets. The aggregate grant date fair value of these options was $2,479. During the years 
ended September 30, 2017 and 2016, certain performance-based targets were achieved and the Company recorded 
stock-based compensation expense of $413 and $620, respectively, related to achievement of those targets. No 
stock-based compensation expense related to these options was recognized during the year ended September 30, 
2018 as the performance period for these options ended during the year ended September 30, 2017. 

Market and Performance-Based Stock Unit Awards 

The Company awards both performance share units, or PSUs, and relative total stockholder return units, or rTSRUs, 
to its executive officers.   

F-24

 
 
   
   
   
 
 
 
 
     
 
   
   
   
      
  
   
      
  
   
      
  
   
   
   
 
 
 
 
 
   
   
 
 
 
 
 
 
 
 
 
   
   
 
The PSUs will vest and result in issuance, or settlement, of common shares for each recipient, based upon the 
recipient’s continued employment with the Company through the settlement date of the award and the Company’s 
achievement of specified research and development milestones. The requisite service period of the PSUs is generally 
2 years. 

The rTSRUs will vest and result in the issuance of common stock based upon the recipient’s continuing employment 
with the Company through the settlement date of the award and the relative ranking of the total stockholder return, 
or TSR, of the Company’s common stock in relation to the TSR of the component companies in the NASDAQ 
Biotech Index over a two-year period based on a comparison of average closing stock prices in specified periods 
noted in the award agreement. The number of market-based rTSRUs awarded represents the target number of shares 
of common stock that may be earned; however, the actual number of shares that may be earned ranges from 0% to 
150% or 200% of the target number, depending on the award agreement and the year of the award. The Company 
used a Monte Carlo model to estimate the grant-date fair value of the rTSRUs. Assumptions and estimates utilized in 
the calculation of the fair value of the rTSRUs include the risk-free interest rate, dividend yield, expected volatility 
based on the historical volatility of publicly traded peer companies and the remaining performance period of the 
award. The table below sets forth the weighted average grant date fair value assumptions used to value the rTSRUs: 

Years Ended September 30,
2017

2016

2018

Risk-free interest rate

Dividend yield

Expected volatility

Remaining performance period (years)

2.18%   
0%   
62%   

1.83 

1.24%   
0%   
66%   

1.99 

0.94%

0%

65%

1.93  

The following table summarizes PSU and rTSRU activity (at target) for the year ended September 30, 2018: 

PSUs

rTSRUs

Weighted
Average
Grant
Date Fair
Value per 
Share

Shares

Weighted
Average
Grant
Date Fair
Value per 
Share

Shares

Unvested at September 30, 2017

Granted
Vested
Cancelled

Unvested at September 30, 2018

(in thousands, except per share data)
 $

 $

70 
25 
(20)   
(5)   
 $
70 

34.51 
77.93 
32.04 
32.04 
50.97 

70 
25 
(25)   
— 
70 

 $

43.07 
84.70 
37.67 
— 
59.96  

A total of 80% of target PSUs and 192.91% of target rTSRUs granted in December 2015 vested during the year 
ended September 30, 2018, resulting in the issuance of an aggregate of 68 common shares, net of share withholding. 

F-25

 
 
 
 
 
 
 
 
 
 
   
   
   
   
   
   
 
 
   
 
 
 
 
 
   
 
 
 
 
 
 
  
  
  
  
  
  
  
  
  
  
  
  
  
Restricted Stock Units

In November 2016, the Company awarded restricted stock units to its employees, which vest as to 50% of the units 
in three years and 50% in four years, provided the employee remains employed with the Company at the time of 
vesting. The fair value of these awards was determined based on the intrinsic value of the stock on the date of grant 
and is recognized as stock-based compensation expense over the requisite service period. The following table 
summarizes the restricted stock unit activity for the year to date period ending September 30, 2018:

Unvested at September 30, 2017

Granted
Vested
Cancelled

Unvested at September 30, 2018

Weighted
Average Grant
Date Fair
Value per 
Share

Restricted 
Stock
Units
(in thousands, except per 
share data)

110   $
—    
—    
(1)   
109   $

30.00 
— 
— 
30.00 
30.00 

Stock-Based Compensation Expense 

The Company recorded the following stock-based compensation expense for the years ended September 30, 2018, 
2017, and 2016: 

Research and development
General and administrative

(in thousands)

  $

  $

6,160   $
9,685    
15,845   $

4,078   $
8,993    
13,071   $

2,882 
6,472 
9,354  

Years Ended September 30,
2017

2016

2018

2018

Years Ended September 30,
2017
(in thousands)

2016

Stock options
rTSRUs
Restricted stock units
PSUs

  $

  $

12,694   $
1,721    
789    
641    
15,845   $

10,442   $
1,267    
694    
668    
13,071   $

8,661 
693 
— 
— 
9,354  

As of September 30, 2018, the Company had an aggregate of $30,064 of unrecognized stock-based compensation 
cost, which is expected to be recognized over a weighted average period of 2.2 years. 

F-26

 
 
   
 
 
 
 
  
  
  
  
  
 
    
       
 
 
 
 
 
 
   
   
 
 
 
 
   
 
 
 
 
 
 
   
   
 
 
 
 
   
   
   
 
11. Net Income Per Share 

Basic and diluted net income per common share was calculated as follows for the years ended September 30, 2018, 
2017, and 2016: 

Basic net income per share:

Numerator:

Net income
Denominator:

Years Ended September 30,
2018
2016
2017
(in thousands, except per share data)

  $

71,956   $

17,710   $

21,666 

Weighted average common shares 
outstanding — basic

19,255    

19,066    

18,929 

Net income per share common share — basic   $

3.74   $

0.93 

 $

1.14 

Diluted net income per share:

Numerator:

Net income
Denominator:

  $

71,956   $

17,710 

 $

21,666 

Weighted average common shares 
outstanding — basic
Dilutive effect of common stock 
equivalents
Weighted average common shares 
outstanding — diluted

Net income per share common share — 
diluted
Anti-dilutive common stock equivalents 
excluded from above

19,255    

19,066 

18,929 

1,395    

341 

295 

20,650    

19,407 

19,224 

  $

3.48   $

0.91 

 $

1.13 

295    

2,161 

1,475  

The impact of certain common stock equivalents were excluded from the computation of diluted net income per 
common share attributable to common stockholders for the years ended September 30, 2018, 2017, and 2016, because 
those options had an anti-dilutive impact due to the assumed proceeds per share using the treasury stock method being 
greater than the average fair value of the Company’s common shares for those periods. 

As of September 30, 2018, 2017, and 2016, the Company excluded unvested performance stock unit awards from the 
calculation of diluted net income per common share as these awards contain performance conditions that would not 
have been achieved as of the end of each reporting period had the measurement period ended as of that date. 

12. Commitments and Contingencies 

Leases 

The Company has two leases located in Watertown, Massachusetts. The first lease, for office and laboratory space at 
500 Arsenal Street, was effective from fiscal 2011 to 2018. During the year ended September 30, 2015, the 
Company amended the lease to expand the rented space and extend the lease term through September 2022. 
Payment escalations specified in the lease agreement, as amended, are accrued such that rent expense is recognized 
on a straight-line basis over the term of occupancy. The amended lease also included a $598 tenant improvement 
allowance from the landlord, which was accounted for as a capital lease obligation.

In connection with the 500 Arsenal Street lease, the Company has a total outstanding letter of credit in the amount of 
$608 as of September 30, 2018 and 2017, collateralized by a money market account. As of September 30, 2018 and 
2017, the Company classified the money market account as long-term restricted cash. 

F-27

 
 
 
 
 
   
   
 
 
 
 
   
     
  
    
 
   
     
  
    
 
   
     
  
  
  
   
   
     
  
  
  
   
     
  
  
  
   
     
  
  
  
   
  
   
  
   
  
   
  
The second lease, for office space, located at 400 Talcott Avenue, was entered into on September 27, 2018 with a 
lease term that extends through August 1, 2024. The lease includes a free rent period as well as escalating rent 
payments over the course of the lease. The net amount of these escalations and the free rent period will be accrued 
and recognized as rent expense on a straight-line basis over the term of the lease. 

For the years ended September 30, 2018, 2017, and 2016, the Company recognized rent expense of $2,033, $2,025, 
and $2,025, respectively, in the consolidated statements of operations. 

Future minimum lease payments under both leases as of September 30, 2018 are as follows: 

Years Ended September 30,

Operating
Leases

Capital
Leases

2019
2020
2021
2022
2023
Thereafter
Total

  $

  $

 $

(in thousands)
2,209 
2,728 
2,803 
2,684 
608 
519 
11,551 

 $

86 
93 
101 
99 
— 
— 
379  

Intellectual Property Licenses 

In 2012 the Company entered into a non-exclusive intellectual property license agreement with a licensor of 
research technology under which the Company was required to pay the third party licensor an upfront license fee 
and additional fees up to the third anniversary of the agreement. In addition, the Company was required to pay 
annual maintenance fees for each year that the agreement remained in effect. During the years ended September 30, 
2017 and 2016, the Company paid $115 and $120, respectively, under the agreement. The license agreement was 
terminated during the year ended September 30, 2017.

During the year ended September 30, 2013, the Company amended an existing license agreement to extend rights to 
patents previously licensed for one of its programs for use in its HCV research. Under the license, the Company is 
obligated to pay milestones totaling up to $5,000 plus low single-digit royalties, for the development and regulatory 
approval of each HCV product outside of the Company’s collaboration with AbbVie and any other collaboration it 
may enter into in the future with a partner that has already licensed these patents. During the year ended September 
30, 2016, the Company paid a $500 milestone payment under this amended agreement as a result of the Company’s 
filing to commence clinical development of its own HCV product candidate which was recorded as a research and 
development expense. The Company stopped further development of its own HCV product candidate in 2016 and 
there were no further payments made under this license. 

Litigation and Contingencies Related to Use of Intellectual Property 

From time to time, the Company may become subject to legal proceedings, claims and litigation arising in the 
ordinary course of business. The Company currently is not a party to any threatened or pending litigation. However, 
third parties might allege that the Company or its collaborators are infringing their patent rights or that the Company 
is otherwise violating their intellectual property rights. Such third parties may resort to litigation against the 
Company or its collaborators, which the Company has agreed to indemnify. With respect to some of these patents, 
the Company expects that it will be required to obtain licenses and could be required to pay license fees or royalties, 
or both. These licenses may not be available on acceptable terms, or at all. A costly license, or inability to obtain a 
necessary license, would have a material adverse effect on the Company’s financial condition, results of operations 
or cash flows. The Company accrues contingent liabilities when it is probable that future expenditures will be made 
and such expenditures can be reasonably estimated. 

F-28

 
 
 
 
 
 
 
   
  
   
  
   
  
   
  
   
  
Indemnification Agreements 

In the ordinary course of business, the Company may provide indemnifications of varying scope and terms to 
customers, vendors, lessors, business partners, and other parties with respect to certain matters including, but not 
limited to, losses arising out of breach of such agreements or from services to be provided to the Company, or from 
intellectual property infringement claims made by third parties. In addition, the Company has entered into 
indemnification agreements with members of its board of directors and its executive officers that will require the 
Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or 
service as directors or officers. The maximum potential amount of future payments the Company could be required 
to make under these indemnification agreements is, in many cases, unlimited. To date, the Company has not 
incurred any material costs as a result of such indemnifications. In addition, the Company maintains officers and 
directors insurance coverage. The Company does not believe that the outcome of any claims under indemnification 
arrangements will have a material effect on its financial position, results of operations or cash flows, and has not 
accrued any liabilities related to such obligations in its financial statements as of September 30, 2018 and 2017. 

13. Income Taxes 

Income before income taxes for all periods presented is from domestic operations, which are the Company’s only 
operations. During the years ended September 30, 2018, 2017, and 2016, the Company recorded income tax expense 
as follows: 

2018

Years Ended September 30,
2017
(in thousands)

2016

Current income tax (expense) benefit:

Federal
State

Deferred income tax (expense) benefit:

Federal
State

  $ (16,449)  $ (10,078)  $ (12,233)
(956)

(2,858)   

(813)   

(2,245)   
387     
  $ (21,165)  $

1,503     
151     

2,136 
159 
(9,237)  $ (10,894)

A reconciliation of the U.S. federal statutory income tax rate to the Company’s effective tax rate is as follows: 

Years Ended September 30,
2017

2016

2018

Federal statutory income tax rate

State taxes, net of federal benefit
Federal research and development tax credit
Remeasurement of net deferred tax assets
Share-based compensation
Other

Effective income tax rate

24.5%   
2.6 
(5.2)
4.2 
(2.8)
(0.6)
22.7%   

35.0%   
2.7 
(7.4)
— 
4.5 
(0.5)
34.3%   

35.0%
2.7 
(3.8)
— 
2.6 
(3.0)
33.5%

F-29

 
 
 
 
 
   
   
 
 
 
 
     
       
       
 
   
     
       
       
 
   
   
 
 
 
 
 
 
 
 
 
 
 
   
   
  
  
   
  
  
   
  
  
   
  
  
   
  
  
   
Net deferred tax assets as of September 30, 2018 and 2017 consisted of the following: 

Deferred tax assets:

Share-based compensation
Accrued expenses
Capitalized research and development expenses
Unrealized loss
Other temporary differences
Total deferred tax assets

  $

Valuation allowance
Net deferred tax assets

Deferred tax liabilities:

Depreciation
Prepaid expenses

Total deferred tax liabilities

Net deferred income tax assets (liabilities)

  $

September 30,

2018

2017

(in thousands)

 $

7,372 
756 
223 
139 
828 
9,318 
— 
9,318 

(798)   
(145)   
(943)   
 $
8,375 

7,899 
1,001 
1,199 
67 
1,171 
11,337 
— 
11,337 

(1,026)
(188)
(1,214)
10,123  

The net deferred tax asset is presented as a long-term asset on the consolidated balance sheets. 

Estimates used to prepare income tax expense are based on the Company’s initial analysis of the Tax Act enacted in 
December 2017. Given the complexity of the act, anticipated guidance from the U. S. Treasury regarding 
implementation of the act, and potential for additional guidance from the SEC and the Financial Accounting 
Standards Board related to the act, these estimates may be adjusted during fiscal 2019 to reflect any such guidance 
provided. While the Company believes it has adequately provided for all tax positions during the year ended 
September 30, 2018, amounts asserted by taxing authorities could materially differ from the Company’s accrued 
positions as a result of uncertain and complex application of tax law and regulations. Additionally, the recognition 
and measurement of certain tax benefits include estimates and judgment by management. Accordingly, the 
Company could record additional provisions or benefits for U.S. federal and state tax matters in future periods as 
new information becomes available.  

After consideration of all the evidence, both positive and negative, the Company determined that no valuation 
allowance was needed for all or a portion of its deferred tax assets as of September 30, 2018 because it is more 
likely than not that the deferred tax assets will be realized. In subsequent periods, the Company may determine that 
it is more likely than not that the deferred tax assets will not be realized and thus, a valuation allowance may be 
recorded against all or any portion of its deferred tax assets on the Company’s consolidated balance sheet with a 
corresponding non-cash charge to income tax expense in the consolidated statements of operations.

The Company files tax returns as prescribed by the tax laws of the jurisdictions in which it operates. In the normal 
course of business, the Company is subject to examination by federal and state jurisdictions, where applicable. The 
Company’s tax years are still open under statute from 2014 to the present. Earlier years may be examined to the 
extent that tax credit or net operating loss carryforwards are used in future periods. During 2018, the Company 
received notice of examination by the Internal Revenue Service (“IRS”) for the year ending September 30, 2016. 
The Company received and agreed to a notice of proposed adjustment from the IRS which was paid in September 
2018, the amount of which was immaterial to the financial statements. The Company is in the process of finalizing 
the completion of the IRS audit. During October 2018, the Company received notice of examination by the 
Massachusetts Department of Revenue (“DOR”) for the years ending September 30, 2015 and September 30, 2016. 
No adjustments have been proposed to date. The Company has not received notice of examination by any other 
jurisdictions for any other tax year open under statute. 

F-30

 
 
 
 
 
 
 
 
 
 
 
   
 
    
 
 
   
  
   
  
   
  
   
  
   
  
   
  
   
  
 
   
  
  
  
   
  
  
  
   
   
   
Uncertain tax positions represent tax positions for which reserves have been established. The Company’s policy is to 
record interest and penalties related to uncertain tax positions as part of income tax expense. A reconciliation of the 
beginning and ending amount of uncertain tax positions is summarized as follows: 

September 30,

2018

2017

Beginning Balance

Additions based on tax positions for the current period
Additions based on tax positions for prior periods
Reductions for tax positions of prior periods

Ending Balance

  $

  $

 $

(in thousands)
1,175 
563 
— 
(59)   
 $

1,679 

745 
134 
355 
(59)
1,175  

The Company does not expect that its uncertain tax position will materially change within the next twelve months.

14. 401(k) Plan 

The Company has a 401(k) plan. This plan covers substantially all employees who meet minimum age and service 
requirements. During the years ended September 30, 2018, 2017, and 2016 the Company recognized $852, $712 and 
$513, respectively, of expense related to its contributions to this plan. 

15. Selected Quarterly Financial Data (unaudited)

Quarterly financial information for fiscal 2018 and 2017 is presented in the following table: 

2018 Quarter Ended

December 31, 201
7

September 30, 201
8

 $

Revenue (1)
Operating expenses
Other income (expense)
Income tax (expense)
Net income
Net income per common share — basic(3)
 $
Net income per common share — diluted(3)  $

Revenue (2)
Operating expenses
Other income (expense)
Income tax (expense) benefit
Net income (loss)
Net income (loss) per common share — 
basic(3)
Net income (loss) per common share — 
diluted(3)

 $

$

$

2017 Quarter Ended

December 31, 201
6

September 30, 201
7

   March 31, 2018    June 30, 2018    
(in thousands, except per share data)
57,262   $
34,622    
1,338    
(3,690)  
20,288    
1.05   $
0.97   $

44,049   $
27,190    
1,066    
(5,370)  
12,555    
0.65   $
0.61   $

38,109   $
23,732    
960    
(3,644)  
11,693    
0.61   $
0.59   $

   March 31, 2017    June 30, 2017    
(in thousands, except per share data)
7,511   $
20,640    
600    
4,103    
(8,426)  

8,959   $
18,465    
549    
3,565    
(5,392)  

10,417   $
17,463    
524    
1,542    
(4,980)  

(0.26) $

(0.28) $

(0.44) $

(0.26) $

(0.28) $

(0.44) $

67,205 
32,753 
1,429 
(8,461)
27,420 
1.41 
1.30  

75,927 
21,632 
660 
(18,447)
36,508 

1.91 

1.86  

(1) During the first quarter of 2018, the Company recognized $15,000 in milestone revenue from AbbVie upon 

achievement of commercialization regulatory approval of AbbVie’s glecaprevir-containing regimen in Japan.  

F-31

 
 
 
 
 
 
   
 
 
 
 
 
   
  
   
  
   
 
 
 
 
 
 
 
 
 
  
  
  
  
 
 
 
 
 
 
 
 
 
 
  
  
  
  
 
 
(2) During the fourth quarter of 2017, the Company recognized $65,000 in milestone revenue from AbbVie upon 

achievement of commercialization regulatory approval of AbbVie’s glecaprevir-containing regimen in the 
U.S. and the EU.
The earnings per share amounts for each quarter may not sum to the fiscal year amounts due to rounding and 
the effect of weighting.

(3)

F-32

Corporate Headquarters
Enanta Pharmaceuticals, Inc.
500 Arsenal Street
Watertown, MA 02472

Investor Inquiries
Investor Inquiries (including requests for a copy of
Enanta’s Form 10-K, available free of charge) should
be directed to:

Enanta Pharmaceuticals, Inc.
500 Arsenal Street
Watertown, MA 02472
Attention: Investor Relations
Phone: 617-607-0800

The 2018 Annual Report on Form 10-K and other
investor information are available in the Investors
section of Enanta’s website at www.enanta.com.

Independent Registered Public Accounting Firm
PricewaterhouseCoopers LLP
101 Seaport Boulevard, Suite 500
Boston, MA 02210

Legal Counsel
Foley Hoag LLP
Seaport West
155 Seaport Boulevard
Boston, Massachusetts 02210

Transfer Agent
Computershare Trust Company, N.A.
250 Royall Street
Canton, MA 02021

Stock Listing
NASDAQ Global Select Market: ENTA

Web Site
www.enanta.com

Management Team
Jay R. Luly, Ph.D.

President, Director and Chief Executive Officer

Nathalie Adda, M.D.

Senior Vice President and Chief Medical Officer

Nathaniel S. Gardiner, J.D.

Senior Vice President and General Counsel

Paul J. Mellett

Senior Vice President, Finance & Administration and
Chief Financial Officer

Timothy D. Ocain, Ph.D.

Senior Vice President, New Product Strategy &
Development

Yat Sun Or, Ph.D.

Senior Vice President, Research & Development and
Chief Scientific Officer

Board of Directors
Bruce L.A. Carter, Ph.D.

Non-Executive Chairman of the Board,
Enanta Pharmaceuticals, Inc.
Former President and Chief Executive Officer,
ZymoGenetics, Inc.

Stephen Buckley, Jr.

Retired partner of Ernst & Young LLP

George S. Golumbeski, Ph.D.

President and Member of the Board of Directors,
GRAIL, Inc.

Jay R. Luly, Ph.D.

President and Chief Executive Officer,
Enanta Pharmaceuticals, Inc.

Kristine Peterson

Former Chief Executive Officer, Valeritas, Inc.

Lesley Russell, MBChB, MRCP

Former Chief Medical Officer, Cephalon, Inc. and
other companies

Terry C. Vance

Private consultant and former biotechnology venture
capital investor

HCV

NASH
 /PBC

HBV

RSV

Enanta Pharmaceuticals, Inc
500 Arsenal Street
Watertown, MA 02472
www.enanta.com

Cover graphics: Molecular model represents glecaprevir, Enanta’s protease inhibitor contained 
in AbbVie’s HCV regimens marketed as MAVYRET™ (U.S.) MAVIRET™ (ex-U.S.)