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Repligen

rgen · NASDAQ Healthcare
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Ticker rgen
Exchange NASDAQ
Sector Healthcare
Industry Medical - Instruments & Supplies
Employees 1001-5000
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FY2010 Annual Report · Repligen
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2010 Annual Report

Our goal is to build an integrated biopharmaceutical company by 

developing and marketing innovative drugs that deliver the benefits  

of protein therapies in the fields of neurology and gastroenterology. 

We have a core competency in large-scale protein manufacturing  

and have out-licensed certain biologics intellectual property which 

provide ongoing sources of revenue.

1

2010 ANNUAL REPORT

Accelerating Biomanufacturing

Advancing Therapeutics

Protecting Innovation

Entered into a five-year supply 
agreement with GE Healthcare for 
recombinant Protein A.

Completed RG1068 Phase 3 trial 
for MRI imaging of the pancreas.

Advanced RG2417 Phase 2b trial 
for bipolar depression.

U.S. patent issued covering  
the use of uridine (RG2417) to 
treat the symptoms of bipolar  
disorder; patent will remain in 
force until 2025.

Acquired “plug and play” 
chromatography technology 
platform; launched Opus™ 
pre-packed columns to expand 
the bioprocessing product 
offering and increase  
market access.

Filed RG2833 IND for  
Friedreich’s ataxia; received 
Orphan Drug Designation.

U.S. patent issued covering  
a recently launched recombinant 
Protein A; patent will remain in 
force until 2028.

Licensed spinal muscular atrophy 
program; identified RG3039 as  
a clinical candidate.

3

2010 ANNUAL REPORT

A letter from Walter C. Herlihy, Ph.D. 

President and Chief Executive Officer

Over the past year we made substantial progress in advancing our pipeline of therapeutic product candidates. We  

completed a Phase 3 clinical trial of RG1068 for MRI imaging of the pancreas, and we made significant progress in  

recruiting patients into our Phase 2b “proof of concept” study of RG2417, a novel therapy for bipolar depression. We expect 

to report results from both the RG1068 and RG2417 clinical studies by the end of the year. Our product candidate for 

Friedreich’s ataxia has advanced to an IND filing for Phase 1 studies. We also bolstered our pipeline through in-licensing  

a potential product for spinal muscular atrophy (SMA) for which toxicology studies are in progress in preparation for 

clinical trials next year.

Sales of our bioprocessing products were negatively impacted last year by the financial crisis; however, we are now seeing a 

return to growth for this business. To further expand our market opportunity, we acquired a “plug and play” chromatography 

platform and launched our first products under the Opus™ brand name. Royalties on Bristol-Myers’ sales of Orencia grew  

by 27%, and we recorded $21.0 million in total revenue and a net loss of $4.0 million. We ended the year with $59.1 million  

in cash and equivalents and no debt.

Over the next twelve months, we anticipate completing our pancreatic imaging and bipolar depression trials, advancement  

of our Friedreich’s ataxia and SMA programs toward clinical trials and significant revenue growth for our bioprocessing  

business. As in the past, we are continuing to seek acquisitions to bolster both our therapeutic pipeline and our biopro-

cessing business. 

I look forward to updating you on our progress during the year. Thank you for your continued support of Repligen.

Walter C. Herlihy, Ph.D. 
August 2, 2010

Preclinical

Phase I

Phase II

Phase III

Market

Bioprocessing Business Biologics Purification

Orencia® Royalties Rheumatoid Arthritis

4

REPLIGEN CORPORATION

Preclinical

Phase I

Phase II

Phase III

Market

RG1068 Pancreatic Imaging

RG2417 Bipolar Disorder

RG2883 Friedreich’s Ataxia

RG3039 Spinal Muscular Atrophy

Development Assets 

Innovative Drugs that Deliver the Benefits of Protein Therapies

RG1068—A GI Hormone for MRI Imaging of the Pancreas

ducts as an intrinsic contrast medium. RG1068, the gastro-

Until fairly recently, endoscopic retrograde cholangiopancre-

atography (ERCP) was the primary means for diagnosing 

and treating patients with suspected pancreatic disease and 

abnormalities. However, ERCP is a costly, invasive procedure 

with significant potential for complications including acute 

pancreatitis, hemorrhage, intestinal perforation and exposure 

to radiation. It is estimated that more than 50,000 patients 

suffer serious complications in the U.S. each year following 

ERCP, and as many as 2,000 patients die.

The advancement of magnetic resonance imaging (MRI) tech-

nology has resulted in the availability of a less expensive, non-

invasive, radiation-free means of evaluating and diagnosing 

intestinal hormone secretin, stimulates the secretion of  

pancreatic fluid into the pancreatic ducts, thereby filling the 

ducts with water which improves the ability to visualize pan-

creatic abnormalities. RG1068-MRI imaging of the pancreas 

provides valuable clinical information to physicians for patients 

who present with abdominal pain and suspected pancreatic 

pathology especially when a surgical or endoscopic proce-

dure is contemplated. Because RG1068-MRI helps to distin-

guish between both normal and abnormal anatomy, it aids in 

avoiding unnecessary and potentially risky ERCP procedures 

and improves triage and pre-surgical planning. There are 

more than 400,000 MRIs conducted in the U.S. and Europe 

each year that could benefit from RG1068, a potential mar-

patients with suspected pancreatic diseases and abnormali-

ket opportunity of $100 million.

ties. An MRI of the pancreas visualizes water in the pancreatic 

6

REPLIGEN CORPORATION

Bipolar disorder is a chronic complex disease associated with considerable morbidity and mortality and  

a high rate of suicide. Bipolar disorder affects more than five million adults worldwide.

We are currently analyzing the images from our Phase 3 

of the disease impairment. While a number of drugs have 

study of RG1068. The goal of the Phase 3 study is to evalu-

demonstrated efficacy for the acute mania symptoms, the 

ate the sensitivity and specificity of RG1068 in combination 

treatment of bipolar depression remains challenging. Charact-

with MRI to improve the detection of structural abnormalities 

e r istics that distinguish bipolar depression from other forms  

of the pancreatic ducts relative to MRI alone. The ongoing 

of depression include a high risk of suicide and psychosis. 

analysis is a “re-read” which was initiated following approval 

Antidepressants are ineffective in the treatment of patients 

by the FDA and EMA based on the determination that the 

with bipolar depression and have been associated with an 

original analysis by a contract research organization was 

increased risk of triggering mania. Atypical antipsychotics 

flawed and therefore inconclusive. We expect to report top-

are used to treat bipolar depression and while effective in 

line results in approximately six months which, if positive, 

some patients, there are troubling side effects, leaving  

may support product registration.

bipolar depression an area of high unmet medical need.

RG2417—A Novel Biological Approach to Treating Bipolar Depression

Bipolar disorder is a chronic complex disease associated 

with considerable morbidity and mortality and a high rate of 

suicide. Bipolar disorder affects more than five million adults 

worldwide and is characterized by “highs” known as mania 

and “lows” known as depression and is usually diagnosed  

in early adulthood. It is estimated that in the U.S. bipolar 

disorder accounts for more than 16 million visits to a physician 

each year and approximately 150,000 hospitalizations. The 

National Institute of Mental Health estimates the total costs 

of bipolar disorder to be $45 billion each year.

Episodes of depression are the most frequent and long-lived 

symptom of bipolar disorder and account for the majority  

RG2417 is an oral formulation of uridine, a biological com-

pound synthesized by the power plant of the cell known as 

the mitochondria. Research has established that mitochondrial 

dysfunction is involved in bipolar disorder establishing the 

basis for treatment. We are conducting a Phase 2b trial of 

RG2417, designed to confirm and extend the results of a 

Phase 2a study in which treatment with RG2417 improved 

the symptoms of bipolar depression with minimal side effects. 

The positive effect of treatment was primarily observed in 

patients with a significant history of disease as determined by 

the number of episodes of mania and depression experienced 

during their lifetime. We expect to report top-line results of 

our study in approximately six months. This novel approach 

for bipolar depression could result in an important new  

7

2010 ANNUAL REPORT

The most effective approach to treatment of diseases characterized by inadequate production of 

a vital protein may be through therapies that replace the deficient protein.

treatment option for patients without the troubling side effects 

and increases production of frataxin protein indicating that 

associated with current therapies.

RG2833 may increase frataxin in patients and arrest disease 

RG2833 and RG3039—Opportunity for protein replacement 
therapy through activation of gene expression in two orphan diseases

progression. We have filed an RG2833 IND, and hope to  

initiate a Phase 1 normal volunteer study this year. RG2833 

has been developed in collaboration with The Scripps 

The most effective approach to treatment of diseases char-

Research Institute and international scientific thought lead-

acterized by inadequate production of a vital protein may be 

ers, and partially funded by the Muscular Dystrophy Associ-

through therapies that replace the deficient protein. We are 

ation, the Friedreich’s Ataxia Research Alliance, GoFar and 

developing two pre-clinical compounds that serve as protein 

the National Ataxia Foundation.

replacement therapies for Friedreich’s ataxia and spinal 

muscular atrophy (SMA) through activation of the defective 

genes that encode the missing proteins. A small increase in 

the protein available has been shown in animal models and 

patient cells to have the potential for a significant benefit. 

Friedreich’s ataxia and SMA are devastating neurodegenera-

tive orphan diseases with 15,000–20,000 patients worldwide 

and for whom there are no treatments.

Friedreich’s ataxia is an inherited neurodegenerative disease 

caused by a single gene defect that results in inadequate 

production of the protein frataxin resulting in a progressive 

degeneration of the nerves controlling muscle movements in 

the arms and legs. Symptoms typically emerge at a young 

age and progress to severe disability or loss of life in early 

adulthood. Preclinical studies have shown that RG2833 

crosses the blood brain barrier, activates the defective gene 

Spinal muscular atrophy (SMA) is an inherited neurodegen-

erative disease caused by a defect in the SMN1 gene result-

ing in low levels of SMN protein. Inadequate production of 

SMN protein leads to progressive damage to the motor neu-

rons, loss of muscle function and in many patients, early 

death. Symptoms of SMA are often evident in infancy and 

typically progress to severe physical disability or loss of life. 

RG3039 has been shown to increase production of SMN in 

patient cells and to extend survival in an animal model of 

SMA. We licensed the rights to RG3039 from Families of 

Spinal Muscular Atrophy who invested approximately $15 

million to discover and conduct the initial development. 

RG3039 has been designated a clinical candidate, and we 

are conducting toxicology studies to evaluate its appropriate-

ness for clinical testing.

8

REPLIGEN CORPORATION

Preclinical

Phase I

Phase II

Phase III

Market

Bioprocessing Business Biologics Purification

Orencia® Royalties Rheumatoid Arthritis

Preclinical

Phase I

Commercial Assets 

Phase III

Phase II

Market

RG1068 Pancreatic Imaging

Expanding and Diversifying the Bioprocessing Business 

RG2417 Bipolar Disorder

For over twenty years, we have been a leading supplier to 

RG2883 Friedreich’s Ataxia

This year we acquired a technology platform for the produc-

the biopharmaceutical industry of Protein A products used in 

RG3039 Spinal Muscular Atrophy

tion of pre-packed, “plug and play” chromatography columns. 

the manufacturing of therapeutic and diagnostic monoclonal 

This patented technology enables economical production of 

antibodies. Monoclonal antibodies are the largest class of 

chromatography columns in a format that is ready for use  

biologic drugs and include important new therapies for rheu-

in the production of a broad range of biopharmaceuticals 

matoid arthritis, osteoperosis and cancer. This year we 

including monoclonal antibodies, vaccines and recombinant 

entered into a five-year supply agreement with GE Healthcare, 

proteins. We will continue to grow our bioprocessing product 

extending the more than 10-year relationship that we have 

line through internal product development initiatives and 

had as their supplier of recombinant Protein A. In addition, we 

acquisition of new products and technologies.

have developed and launched a new recombinant Protein A 

product and subsequently received a U.S. patent this year 

covering the product, which will remain in force until 2028. 

Sales of our bioprocessing products and royalties that we 

receive from licensing of a U.S. patent to Bristol-Myers 

Squibb covering their drug Orencia® resulted in total revenue 

We are seeking to leverage our expertise in protein manufac-

for the year of $21 million, which allowed us to continue to 

turing through developing and commercializing new products 

advance our therapeutic pipeline and bioprocessing busi-

that improve efficiency in biopharmaceutical manufacturing. 

ness and maintain our cash reserves for future acquisitions.

Annual Report Design by Curran & Connors, Inc. / www.curran-connors.com

41 Seyon Street
Building #1, Suite 100
Waltham, MA 02453
phone 781.250.0111
fax 781.250.0115
info@repligen.com

www.repligen.com

2010 Financial Information on Form 10-K

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

FORM 10-K

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

EXCHANGE ACT OF 1934

‘ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES

EXCHANGE ACT OF 1934

For the fiscal year ended March 31, 2010
OR

For the transition period from

to

Commission file number: 000-14656

REPLIGEN CORPORATION

(Exact name of Registrant as specified in its charter)

Delaware
(State or other jurisdiction of
incorporation or organization)

41 Seyon Street, Bldg. 1, Suite 100
Waltham, MA
(Address of Principal executive offices)

04-2729386
(I.R.S. Employer
Identification No.)

02453
(Zip Code)

Registrant’s telephone number, including area code: (781) 250-0111

Securities registered pursuant to Section 12(b) of the Act:
Title of Each Class
Common Stock, $0.01 Par Value Per Share
Series A Junior Participating Preferred Stock Purchase Rights
Name of Each Exchange on Which Registered
The NASDAQ Stock Market LLC
Securities registered pursuant to Section 12(g) of the Act: None
Title of Each Class

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ‘ No È.
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 ‘ No È.
Indicate by checkmark 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 È No ‘.

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Website, if any, every Interactive Data
File required to be submitted and posted 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 and post such files). Yes ‘ No ‘.

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (§229.405 of this chapter) 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, or a smaller reporting

company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.
(Check one):

Large accelerated filer ‘

Accelerated filer È

Non-accelerated filer ‘
(Do not check if a smaller
reporting company)

Smaller reporting company ‘

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yes ‘ No È.
The aggregate market value of the voting and non-voting common equity held by non-affiliates as of September 30, 2009, the last business

day of the registrant’s most recently completed second fiscal quarter, was approximately $154,098,617.

The number of shares of outstanding of the registrant’s common stock as of May 31, 2010 was 30,766,807.

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the Company’s definitive Proxy Statement in connection with the 2010 annual meeting of Stockholders are incorporated

by reference into Part III of this Form 10-K.

Table of Contents

PART I

Item 1.

Business . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Item 1A. Risk Factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Item 1B. Unresolved Staff Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Item 2.

Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Item 3.

Legal Proceedings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Item 4.

Removed and Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

PART II

Item 5.

Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases

of Equity Securities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Item 6.

Selected Financial Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Item 7.

Management’s Discussion and Analysis of Financial Condition and Results of Operations . . .

Item 7A. Quantitative and Qualitative Disclosures About Market Risk . . . . . . . . . . . . . . . . . . . . . . . . . .

Item 8.

Financial Statements and Supplementary Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Item 9.

Changes in and Disagreements with Accountants on Accounting and Financial Disclosure . . .

Item 9A. Controls and Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Item 9B. Other Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

PART III

PART IV

Item 15.

Exhibits and Financial Statement Schedules

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SIGNATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

PAGE

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2

Item 1.

BUSINESS

PART I

The following discussion of our business contains forward-looking statements that involve risks and
uncertainties. When used in this report, the words “intend,” “anticipate,” “believe,” “estimate,” “plan” and
“expect” and similar expressions as they relate to us are included to identify forward-looking statements. Our
actual results could differ materially from those anticipated in these forward-looking statements and are a result of
certain factors, including those set forth under “Risk Factors” and elsewhere in this Annual Report on Form 10-K.

Repligen Corporation (“Repligen,” the “Company” or “we”) is a biopharmaceutical company focused on the
development and commercialization of innovative therapies that harness biological pathways and deliver value to
patients and clinicians in neurology, gastroenterology and orphan diseases. We are currently conducting a
number of drug development programs for diseases such as pancreatitis, bipolar disorder, Friedreich’s ataxia and
spinal muscular atrophy. We also have a bioprocessing business that focuses on the development and
commercialization of products that are used for the production of biopharmaceuticals. In addition, we receive
royalties from Bristol-Myers Squibb Company (“Bristol”) on their net sales in the United States of their product
Orencia®. We seek to invest the profits from our current commercial products, royalty and other revenues, as
well as use our existing financial resources to advance the development of our therapeutic product candidates and
our bioprocessing business.

We were incorporated in May 1981, under the laws of the State of Delaware. Our principal executive offices

are at 41 Seyon Street, Waltham, Massachusetts 02453 and our telephone number is (781) 250-0111.

Currently Marketed Products

We currently sell a line of commercial bioprocessing products based on Protein A, as well as single or
limited campaign use pre-packed chromatography columns, which are used in the production of monoclonal
antibodies and other biopharmaceutical manufacturing applications.

Protein A Products for Antibody Manufacturing

Protein A is widely used in the purification of therapeutic monoclonal antibodies. Most therapeutic
monoclonal antibodies are manufactured by the fermentation of mammalian cells that express the monoclonal
antibody. The monoclonal antibody is typically produced by a process in which an impure fermentation broth
containing the desired monoclonal antibody is passed over a solid support to which Protein A has been
chemically attached or “immobilized.” The immobilized Protein A binds the monoclonal antibody while other
impurities are washed away. The monoclonal antibody is then recovered from the support in a substantially
purified form.

We manufacture and market several products based on recombinant forms of Protein A. Our primary
customers incorporate our Protein A products into their proprietary monoclonal antibody purification products
that they sell directly to the biopharmaceutical industry. We primarily supply Protein A products to GE
Healthcare (“GEHC”) under a supply agreement which extends through 2015. The majority of our product sales
for the last three years have been sales of Protein A products and related detection assays.

The global monoclonal antibody market was valued at approximately $40 billion in 2009 and is expected to
exceed $65 billion by 2015. Examples of therapeutic antibodies include Enbrel® and Remicade® for rheumatoid
arthritis and other inflammatory disorders, and Rituxan® for rheumatoid arthritis and Non-Hodgkin’s
Lymphoma, among others. There are more than 200 additional monoclonal antibodies in various stages of
clinical testing which may lead to additional growth of the antibody market and in turn, increased demand for
Protein A.

3

SecreFlo® for Pancreatic Diagnosis

We discontinued distribution of SecreFlo® in the second quarter of fiscal year 2009 due to the expiration of

our agreement with ChiRhoClin, Inc. Previously, we recorded sales of SecreFlo®, a synthetic form of porcine
(pig-derived) secretin. SecreFlo® is approved by the U.S. Food and Drug Administration (“FDA”) as an aid in
the diagnosis of chronic pancreatitis and gastrinoma (a form of cancer) and as an aid during endoscopic
retrograde cholangiopancreatography (“ERCP”), a gastrointestinal procedure.

Intellectual Property on Monoclonal Antibody and Antibody Fusion Products

Orencia® (CTLA4-Ig) Royalties

CTLA4 is a key regulator of the activity of the immune system. CTLA4 “turns off” the immune system after

it has successfully cleared a bacterial or viral infection by blocking the activation of T-cells, the immune cells
responsible for initiating an immune response. CTLA4-Ig’s mechanism of action is different from the current
therapies for autoimmune disease or organ transplant rejection, thus it may provide a treatment for patients who
are refractory to existing therapies. In the 1990’s, our collaborators at the University of Michigan and the U.S.
Navy demonstrated in animal models that a fusion protein consisting of fragments of CTLA4 and an antibody
(“CTLA4-Ig”) could be used to treat certain autoimmune diseases. This research finding resulted in the granting
of U.S. patent No. 6,685,941 (“the ‘941 Patent”) covering the treatment of certain autoimmune disorders
including rheumatoid arthritis with CTLA4-Ig.

In December 2005, the FDA approved Bristol’s application to market CTLA4-Ig, under the brand name
Orencia®, for treatment of rheumatoid arthritis. In January 2006, Repligen and the University of Michigan jointly
filed a lawsuit against Bristol in the United States District Court for the Eastern District of Texas for
infringement of the ‘941 Patent. In April 2008, Repligen and the University of Michigan entered into a settlement
agreement with Bristol pursuant to which, Bristol made an initial payment of $5 million to Repligen and agreed
to pay us royalties on the U.S. net sales of Orencia® for any clinical indication at a rate of 1.8% for the first $500
million of annual sales, 2.0% for the next $500 million and 4.0% of annual sales in excess of $1 billion for each
year from January 1, 2008 until December 31, 2013.

The ‘941 Patent is owned by the University of Michigan and exclusively licensed to Repligen. In
consideration of this exclusive license, Repligen agreed to pay the University of Michigan 15% of all royalty
income received, after deducting legal expenses. There are no annual or other fees associated with this
agreement. Under this agreement, since its inception through fiscal year 2010, Repligen has paid approximately
$2,438,000 to the University of Michigan.

Erbitux®

Erbitux® is a monoclonal antibody developed by ImClone Systems Incorporated (“ImClone”) which was
approved by the FDA in February 2004 for the treatment of certain forms of colon cancer and in March 2006 for
the treatment of head and neck cancer. Erbitux® is manufactured with a cell line which contains certain genetic
technologies (“DNA enhancers”) which increase the productivity of a cell line. A U.S. patent covering the use of
DNA enhancers, which expired in May of 2004, was assigned to The Massachusetts Institute of Technology
(“MIT”) and exclusively licensed to Repligen. In May 2004, Repligen and MIT jointly filed a lawsuit against
ImClone in U.S. District Court for Massachusetts alleging that ImClone had infringed our patent rights in its
production of Erbitux®. In September 2007, Repligen and MIT entered into a settlement agreement under which
ImClone was granted a license to the DNA enhancer patent and certain other intellectual property in exchange for
a payment of $65,000,000.

Research and Development

For the past three years, we have devoted substantial resources to the research and development of

therapeutic product candidates and our commercial products and product candidates discussed herein. We spent

4

$14,160,000, $12,772,000 and $7,241,000 in fiscal years 2010, 2009 and 2008, respectively, on company-
sponsored research and development activities.

Development Stage Products

Secretin for MRI Imaging of the Pancreas

Secretin is a well-known gastrointestinal hormone produced in the small intestine that regulates the function

of the pancreas as part of the process of digestion. We are currently evaluating the sensitivity and specificity of
secretin in combination with MRI to improve the detection of structural abnormalities of the pancreas relative to
MRI alone. Detailed visual assessment of the pancreatic ducts and identification of structural abnormalities is
important in the assessment, diagnosis and treatment of diseases such as acute and chronic pancreatitis. The use
of secretin during MRI harnesses the natural biologic properties of secretin, which signals the release of water-
rich fluids into the ducts of the pancreas. Improvement in the detection and delineation of normal and abnormal
structures with MRI is attractive for patient care as it can obviate the need for more invasive endoscopic
procedures.

We initiated a Phase 2 clinical trial in June 2006 to evaluate the use of RG1068, synthetic human secretin, as

an agent to improve the detection of structural abnormalities of the pancreatic ducts during MRI imaging of the
pancreas. This was a multi-center, baseline controlled, single dose study in which 76 patients with a history of
pancreatitis received an RG1068-MRI and an MRI alone of the pancreas. In May 2007, we announced positive
results from this Phase 2 clinical trial. The study showed an improvement in sensitivity of detection of structural
abnormalities of the pancreatic duct of approximately 20% with no loss in specificity. In addition, the study
showed highly significant increases in the following three assessments: physician confidence in their ability to
identify structural abnormalities, the number of pancreatic duct segments visualized, and improvement in the
overall quality of the MRI images. Our Phase 2 data was reviewed by the FDA and served as the basis for a
pivotal, Phase 3 study.

This Phase 3 clinical trial was initiated in March 2008 and completed in December 2009. This was a multi-

center, baseline controlled, single dose study in which 258 patients with a history of pancreatitis at 23 clinical
sites within the United States and Canada received an MRI of the pancreas with and without RG1068. The
primary objectives of the Phase 3 study were to demonstrate that RG1068 increases the sensitivity in detecting
structural abnormalities of the pancreas by MRI, with minimal loss of specificity. The predetermined criteria for
a successful study included the achievement of a statistically significant improvement in sensitivity with minimal
loss in specificity from two of the three central radiologists reading the MRI images. In this study, one radiologist
achieved a statistically significant improvement in sensitivity with RG1068, while a second radiologist showed a
trend but did not achieve statistical significance. There was minimal loss in specificity for all radiologists.

Based on numerous deficiencies with the analysis of the radiographic images by the contract research
organization hired to oversee analysis of the Phase 3 trial data, we submitted a request to the FDA and the
European Medicines Agency (“EMA”) to re-analyze the Phase 3 data set (“Phase 3 re-read”). In May 2010, the
FDA and EMA approved our plan for a re-analysis of images obtained from the Phase 3 trial and we anticipate
that preliminary results will be available by the end of fiscal year 2011, ending on March 31, 2011. We believe
that a successful Phase 3 re-read may provide the basis for filing a New Drug Application (“NDA”) with the
FDA for approval to market RG1068 for this use in the United States.

We have received an Orphan Drug designation from the FDA covering the use of RG1068 in MRI which,
provided we are the first company to receive FDA approval for this use of secretin, will provide seven years of
marketing exclusivity in the United States following approval of the NDA. We also have received “fast track”
designation from the FDA which may provide the basis for an expedited review of this NDA by the FDA.

5

Uridine for Bipolar Depression

Uridine is a biological compound essential for multiple biosynthetic processes including the synthesis of

DNA and RNA, the basic hereditary material found in all cells and numerous other factors essential for cell
metabolism. Uridine is synthesized by the power plant of the human cell known as the mitochondria. The
rationale for uridine therapy in central nervous system (“CNS”) disorders is supported by pre-clinical and clinical
research. Researchers at McLean Hospital previously demonstrated that uridine is active in a well-validated
animal model of depression. Literature reports indicate that certain genes that encode for mitochondrial proteins
are significantly down-regulated in the brains of bipolar patients. This insight suggests that the symptoms of
bipolar disorder may be linked to dysregulation of energy metabolism in the brain.

Bipolar disorder, also known as manic depression, is a chronic illness marked by extreme changes in mood,

thought, energy and behavior in which a person’s mood alternates between the “poles” of mania (highs) and
depression (lows). Bipolar disorder affects more than 5 million adults worldwide and is usually diagnosed in late
adolescence or early adulthood. Bipolar disorder is associated with substantial morbidity and mortality, ranking
worldwide behind only unipolar depression and alcohol abuse among psychiatric illnesses for related disabilities
and overall economic burden of illness. The average lifetime financial burden of bipolar disorder in the United
States is more than $600,000 per patient. Although lithium and anticonvulsants such as valproic acid have
substantially improved the prognosis of bipolar disorder, many individuals are unable to tolerate treatment-
related side effects, and incomplete clinical response, lack of compliance in taking medication, and relapse
remain common clinical problems.

In March 2006, we initiated a Phase 2a clinical trial of RG2417, an oral formulation of uridine, in patients

with bipolar depression. This was a multi-center, dose escalating study in 83 patients which compared daily, oral
dosing with either RG2417 or a placebo for six weeks. Patients were evaluated weekly for the safety and
effectiveness of RG2417 on the symptoms of bipolar depression. The study showed a statistically significant
improvement in the symptoms of depression over the six-week course of treatment in the patients treated with
RG2417 when compared to placebo as measured by the Montgomery-Asberg Depression Rating Scale. RG2417
was well tolerated by patients with a safety profile similar to those treated with a placebo. Our Phase 2a data was
reviewed by the FDA and served as the basis for a Phase 2b study.

In November 2008, we initiated this Phase 2b proof-of-concept clinical trial for RG2417 as a potential

treatment for the depressive symptoms associated with bipolar disorder. This study, currently in progress, is a
multi-center, randomized, double-blind, placebo-controlled clinical trial in which approximately 150 patients
with bipolar depression will receive either RG2417 or placebo twice daily for eight weeks. We anticipate that
preliminary results from this Phase 2b clinical trial will be available by the end of fiscal year 2011, ending on
March 31, 2011.

Histone Deacetylase Inhibitors for Friedreich’s Ataxia

Friedreich’s ataxia is an inherited neurodegenerative disease caused by a single gene defect that results in

inadequate production of the protein frataxin. Low levels of frataxin lead to degeneration of both the nerves
controlling muscle movements in the arms and legs and the nerve tissue in the spinal cord. Symptoms of
Friedreich’s ataxia typically emerge between the ages of five and fifteen and often progress to severe disability,
incapacitation or loss of life in early adulthood. There are approximately 15,000 patients worldwide with
Friedreich’s ataxia. There is currently no treatment for Friedreich’s ataxia.

In April 2007, we entered into an exclusive commercial license (the “Scripps License Agreement”) with The

Scripps Research Institute (“Scripps”) for intellectual property covering compounds which may have utility in
treating Friedreich’s ataxia. Our preclinical studies with several chemically synthesized libraries of compounds
have identified selective HDAC inhibitors. Some of these compounds increase production of the protein frataxin
which may have the potential to arrest disease progression in patients with Friedreich’s ataxia. Repligen is
currently developing RG2833, a selective histone deacetylase 3 (“HDAC-3”) inhibitor for the treatment of

6

Friedreich’s ataxia. We recently filed an Investigational New Drug (“IND”) application with the FDA for a Phase
1 study for a double-blind, single ascending dose study in healthy volunteers to evaluate the pharmacokinetic and
safety profile of RG2833 in up to 40 subjects. This study will also evaluate the pharmacodynamic response of
various biomarkers in peripheral blood to RG2833. We have received an Orphan Drug designation from the FDA
for RG2833, which, if we are the first company to obtain market approval for RG2833 for Friedreich’s ataxia,
will provide seven years of marketing exclusivity in the United States following NDA approval.

DcpS Inhibitors for Spinal Muscular Atrophy

We are pursuing development of a drug that targets the scavenger mRNA decapping enzyme, DcpS, for

treatment of patients with spinal muscular atrophy (“SMA”). Our inhibitors have the potential to be the first in
class treatment for this disease. SMA is an inherited neurodegenerative disease in which a defect in the survival
motor neuron gene (“SMN”) results in low levels of the protein SMN and leads to progressive damage to motor
neurons, loss of muscle function and, in many patients, early death.

On October 22, 2009, we entered into an exclusive worldwide commercial license agreement (“FSMA
License Agreement”) with Families of Spinal Muscular Atrophy (“FSMA”). Pursuant to the FSMA License
Agreement, we obtained an exclusive license to develop and commercialize certain patented technology and
improvements thereon, owned or licensed by FSMA, relating to compounds which may have utility in treating
SMA. If all milestones are achieved, total financial obligations under this agreement, including milestone
payments, sublicense fees, and other charges, could total approximately $16,000,000.

Repligen’s compounds, known as DcpS inhibitors, increase the production of SMN in preclinical studies of
cells derived from patients. Further preclinical testing of these compounds in models of SMA has demonstrated
significantly increased survival, suggesting potential clinical utility. Repligen is currently evaluating a lead DcpS
inhibitor in preclinical studies for future clinical trials in patients with SMA.

Sales and Marketing

We sell our bioprocessing products primarily through value-added resellers such as GEHC as well as
through distributors in certain foreign markets. Prior to its discontinuation in the second quarter of fiscal year
2009, we marketed SecreFlo® directly to hospital-based gastroenterologists in the United States.

Significant Customers and Geographic Reporting

Customers for our bioprocessing products include chromatography companies, diagnostics companies,

biopharmaceutical companies and laboratory researchers. In April 2008, we settled our litigation with Bristol
regarding their sales of Orencia® for which we now receive a royalty. For fiscal years 2010 and 2009, royalty
revenue from Bristol represented 43% and 46% of total revenues, respectively. Our largest bioprocessing
customer accounted for 36%, 36% and 72% of total revenues in fiscal years 2010, 2009 and 2008, respectively.
In fiscal year 2008, another bioprocessing customer also represented 16% of total revenue.

In fiscal years 2010, 2009 and 2008, total revenues from sales to customers in the United States were
approximately 57%, 59% and 32%, respectively. During the same fiscal periods, total revenues generated though
sales to customers in Sweden were 36%, 37% and 61%, respectively.

Employees

As of May 6, 2010, we had 68 employees. Of those employees, 50 were engaged in research, development

and manufacturing and 18 were in administrative and marketing functions. Thirty-one of our employees hold
doctorates or other advanced degrees. Each of our employees has signed a confidentiality agreement. None of our
employees are covered by collective bargaining agreements.

7

Patents, Licenses and Proprietary Rights

Repligen actively pursues patent protection in the United States and in major countries abroad and believes
that patents are an important element in the protection of our competitive and proprietary position. Other forms
of protection, including trade secrets, orphan drug status and know-how, are also considered important elements
of our proprietary strategy. As further described below, Repligen owns or has exclusive rights to a number of
U.S. patents and U.S. pending patent applications as well as corresponding foreign patents and patent
applications. The expiration of key patents owned or licensed by us or the failure of patents to issue on pending
patent applications could create increased competition, with potential adverse effects on our business prospects.
For each of our license agreements where we license the rights to patents or patent applications, the license will
terminate on the day that the last to expire patent covered by each such license agreement expires.

We also rely upon trade secret protection for our confidential and proprietary information. Our policy is to
require each of our employees, consultants, business partners and significant scientific collaborators to execute
confidentiality agreements upon the commencement of an employment, consulting or business relationship with
us. These agreements provide that all confidential information developed or made known to the individual during
the course of the individual’s relationship with us is to be kept confidential and not disclosed to third parties
except in specific circumstances. In the case of employees and consultants, the agreements generally provide that
all inventions conceived by the individual in the course of rendering services to Repligen shall be our exclusive
property.

CTLA4-Ig

The ‘941 patent was issued in February 2004, covering the use of CTLA4-Ig to treat specific autoimmune

disorders including rheumatoid arthritis and multiple sclerosis. The patent is assigned to the University of
Michigan and the U.S. Navy and is exclusively licensed to Repligen. In April 2008, Repligen granted Bristol an
exclusive sublicense to this patent (see “Legal Proceedings”).

Uridine

In 2009, Repligen entered into an exclusive license agreement with McLean Hospital for the worldwide
rights to an internationally filed patent application which covers the use of uridine in the treatment of patients
with bipolar disorder. Repligen has recently received a Notice of Allowance from the U.S. Patent and Trademark
Office for this patent which, upon issue, will remain in force until 2025 prior to any regulatory extensions. Under
the terms of the license agreement, McLean received an upfront payment, and is eligible to receive payments
upon certain product development milestones and royalties upon successful commercialization of uridine for
bipolar disorder. Foreign equivalents of this patent are being prosecuted outside of the United States.

Protein A

We own a broad U.S. patent covering recombinant Protein A, which expired in September 2009, as well as

significant know-how in the manufacture of high-purity Protein A. We recently were granted U.S. Patent
No. 7,691,608 B2, “Nucleic Acids Encoding Recombinant Protein A,” which claims a recombinant gene that
encodes a Protein A molecule with an amino acid sequence identical to that of the natural Protein A molecule
which has long been commercialized for bioprocessing applications. This U.S. patent will remain in effect until
2028. Foreign equivalents of this patent are being prosecuted outside of the United States.

Histone Deacetylase Inhibitors

Repligen has entered into an exclusive license agreement with The Scripps Research Institute for worldwide
rights to a patent application claiming compounds and methods for treating Friedreich’s ataxia with inhibitors of
histone deacetylase (“HDAC”). We have identified the specific HDAC that is the target of these inhibitors and
have filed additional patent applications claiming methods and compositions for treating Friedreich’s ataxia.
These patent applications are currently being prosecuted in the United States and abroad.

8

Spinal Muscular Atrophy

In 2009, Repligen entered into an exclusive license agreement with a non-profit organization, the Families
of Spinal Muscular Atrophy (“FSMA”), for worldwide rights to patent applications related to compositions and
methods for the treatment of spinal muscular atrophy. FSMA had funded the development of these compounds
and identified a novel enzyme target (“DcpS”) that these compounds inhibit. Repligen is prosecuting these patent
applications in the U.S. and abroad.

Competition

Our bioprocessing products compete on the basis of quality, performance, cost effectiveness, and

application suitability with numerous established technologies. Additional products using new technologies that
may be competitive with our products may also be introduced. Many of the companies selling or developing
competitive products have financial, manufacturing and distribution resources significantly greater than ours.

The field of drug development is characterized by rapid technological change. New developments are
expected to continue at a rapid pace in both industry and academia. There are many companies, both public and
private, including large pharmaceutical companies, chemical companies and specialized biotechnology
companies, engaged in developing products competitive with products that we have under development. Many of
these companies have greater capital, human resources, research and development, manufacturing and marketing
experience than we do. They may succeed in developing products that are more effective or less costly than any
that we may develop. These competitors may also prove to be more successful than we are in production and
marketing. In addition, academic, government and industry-based research groups compete intensely with us in
recruiting qualified research personnel, in submitting patent filings for protection of intellectual property rights
and in establishing corporate strategic alliances. We cannot be certain that research, discoveries and commercial
developments by others will not render any of our programs or potential products noncompetitive.

Manufacturing

Protein A for Antibody Manufacturing

We manufacture Protein A bioprocessing products from recombinant strains of bacteria. We manufacture
Protein A for GEHC under a supply agreement which extends through 2015. We purchase raw materials from
more than one commercially established company and believe that the necessary raw materials are currently
commercially available in sufficient quantities necessary to meet market demand. We utilize our own facility and
third parties to carry out certain fermentation and recovery operations, while the purification, immobilization,
packaging and quality control testing of our Protein A bioprocessing products are conducted at our facilities. We
are ISO 9001 certified and utilize a formal quality system to maintain process control, traceability, and product
conformance. We also practice continuous improvement initiatives based on routine internal audits, customer
feedback and audits performed by our partners and customers. In addition, our business continuity management
system focuses on key areas such as contingency planning, security stocks and off-site storage of raw materials
and finished goods to ensure continuous supply of our products.

Therapeutic Product Candidates

We currently rely, and will continue to rely for at least the next few years, upon contract manufacturers for
both the procurement of raw materials and the production of our product candidates for use in our clinical trials.
Our product candidates will need to be manufactured in a facility and by processes that comply with the FDA’s
good manufacturing practices and other similar regulations. It may take a substantial period of time to begin
manufacturing our products in compliance with such regulations. If we are unable to establish and maintain
relationships with third parties for manufacturing sufficient quantities of our product candidates and their
components that meet our planned time and cost parameters, the development and timing of our clinical trials
may be adversely affected.

9

Government Regulation

The development of drug candidates is subject to regulation in the United States by the FDA and abroad by

foreign equivalents. Product development and approval within the FDA regulatory framework usually takes a
significant number of years and involves the expenditure of substantial capital resources. Timelines for
development are uncertain.

Before clinical testing in the United States of any drug candidate may begin, FDA requirements for

preclinical efficacy and safety must be completed. Required toxicity testing typically involves characterization of
the drug candidate in several animal species. Safety and efficacy data are submitted to the FDA as part of an
Investigational New Drug application and are reviewed by the FDA prior to the commencement of human
clinical trials.

Clinical trials involve the administration of the drug to human volunteers or patients under the supervision

of a qualified investigator, usually a physician, with an FDA-approved protocol. Human clinical trials are
typically conducted in three sequential phases:

•

•

•

Phase 1 clinical trials represent the initial administration of the investigational drug to a small group of
human subjects to test for safety (pharmacovigilance), dose tolerability, absorption, biodistribution,
metabolism, excretion and clinical pharmacology and, if possible, to gain early evidence regarding
efficacy and potential biomarkers.

Phase 2 clinical trials typically involve a small sample of the actual intended patient population and
seek to assess the efficacy of the drug for specific targeted indications, to determine dose tolerance and
the optimal dose range, and to gather additional information relating to safety and potential adverse
effects.

Once an investigational drug is found to have some efficacy and an acceptable safety profile in the
targeted patient population, Phase 3 clinical trials are initiated to establish further clinical safety and
efficacy of the investigational drug in a broader sample of the general patient population at multiple
study sites in order to determine the overall risk-benefit ratio of the drug and to provide an adequate
basis for product approval. The Phase 3 clinical development program consists of expanded, large-scale
studies of patients with the target disease or disorder to obtain definitive statistical evidence of the
efficacy and safety of the proposed product.

All data obtained from a comprehensive development program are submitted in an NDA to the FDA and the
corresponding agencies in other countries for review and approval. The NDA includes information pertaining to
clinical studies and the manufacture of the new drug. Review of an NDA by the FDA can be a time-consuming
process and the FDA may request that we submit additional data or carry out additional studies.

Available Information

We maintain a website with the address www.repligen.com. We are not including the information contained

on our website as a part of, or incorporating it by reference into, this annual report on Form 10-K. We make
available free of charge through our website our annual reports on Form 10-K, quarterly reports on Form 10-Q
and current reports on Form 8-K, and amendments to these reports, as soon as reasonably practicable after we
electronically file such materials with, or furnish such materials to, the Securities and Exchange Commission.
Our Code of Business Conduct and Ethics is also available free of charge through our website.

In addition, the public may read and copy any materials that we file with the Securities and Exchange

Commission at the Securities and Exchange Commission’s Public Reference Room at 100 F Street, NE,
Washington, D.C. 20549. The public may obtain information on the operation of the Public Reference Room by
calling the Securities and Exchange Commission at 1-800-SEC-0330. Also, our filings with the Securities and
Exchange Commission may be accessed through the Securities and Exchange Commission’s Electronic Data
Gathering, Analysis and Retrieval (EDGAR) system at www.sec.gov.

10

Item 1A. RISK FACTORS

Investors should carefully consider the risk factors described below before making an investment decision.

If any of the events described in the following risk factors occur, our business, financial condition or results
of operations could be materially harmed. In that case the trading price of our common stock could decline, and
investors may lose all or part of their investment. Additional risks and uncertainties that we are unaware of or
that we currently deem immaterial may also become important factors that affect Repligen.

This annual report on Form 10-K contains forward looking statements that involve risks and uncertainties.

Our actual results could differ materially from those anticipated in these forward looking statements as a result of
certain factors, including the risks faced by us described below and elsewhere in this annual report on Form 10-K.

We are dependent on others to develop, conduct clinical trials for, manufacture, market and sell our
principal products.

We conduct some of our development activities, and conduct most of our commercialization activities,
through collaborations. These collaborations include academic researchers as well as contracts with vendors. Our
collaborations are heavily dependent on the efforts and activities of our collaborative partners. Our existing and
any future collaborations may not be technically or commercially successful. For example, if any of our
collaborative partners were to breach or terminate an agreement with us, reduce its funding or otherwise fail to
conduct the collaboration successfully, we may need to devote additional internal resources to the program that is
the subject of the collaboration, scale back or terminate the program or seek an alternative partner, any of which
could lead to delays in development and/or commercialization of our products.

We depend on, and expect to continue to depend on, a limited number of customers for a high percentage
of our revenues.

As a result, the loss of, or a significant reduction in orders from, any of these customers would significantly

reduce our revenues and harm our results of operations. If a large customer purchases fewer of our products,
defers orders or fails to place additional orders with us, our revenue could decline, and our operating results may
not meet market expectations. In addition, if those customers order our products, but fail to pay on time or at all,
our liquidity and operating results could be materially and adversely affected.

Royalty revenue from Bristol-Myers Squibb Company for sales of Orencia® could fail to materialize.

Our royalty agreement with Bristol provides for us to receive payments from Bristol based on their net sales

of their Orencia® product in the United States. We have no control over Bristol’s sales and marketing practices
for Orencia® and Bristol has no obligation to use commercially reasonable efforts to sell Orencia®. Bristol’s sales
could be significantly impacted by regulatory and market influences beyond our control, resulting in low or even
no royalty revenue for us.

Our research activities may not identify a clinical candidate with appropriate efficacy, safety and
pharmacology to support clinical trials in humans.

In order to conduct phase 1 clinical trials in humans, we must first demonstrate suitable efficacy, safety and
pharmacology characteristics of any potential drug candidates. If we are unsuccessful in these efforts, we may be
forced to identify alternative drug candidates at substantial cost, or possibly abandon certain pre-clinical research
activities.

11

Our clinical trials may not be successful and we may not be able to develop and commercialize related
products.

In order to obtain regulatory approvals for the commercial sale of our future therapeutic products, we and

our collaborative partners will be required to complete extensive clinical trials in humans to demonstrate the
safety and efficacy of the products. We have limited experience in conducting clinical trials.

The submission of an IND application may not result in FDA authorization to commence clinical trials. If
clinical trials begin, we or our collaborative partners may not complete testing successfully within any specific
time period, if at all, with respect to any of our products. Furthermore, we, our collaborative partners, or the
FDA, may suspend clinical trials at any time on various grounds, including a finding that the subjects or patients
are being exposed to unacceptable health risks. Clinical trials, if completed, may not show any potential product
to be safe or effective. Thus, the FDA and other regulatory authorities may not approve any of our potential
products for any indication.

The rate of completion of clinical trials is dependent in part upon the rate of enrollment of patients. Patient
enrollment is a function of many factors, including the size of the patient population, the proximity of patients to
clinical sites, the eligibility criteria for the study, and the existence of competitive clinical trials. Delays in
planned patient enrollment may result in increased costs and delays in completion of clinical trials.

We may not obtain regulatory approvals; the approval process is costly and lengthy.

We must obtain regulatory approval for our ongoing development activities and before marketing or selling
any of our future therapeutic products. We may not receive regulatory approvals to conduct clinical trials of our
products or to manufacture or market our products. In addition, regulatory agencies may not grant such approvals
on a timely basis or may revoke previously granted approvals.

The process of obtaining FDA and other required regulatory approvals is lengthy and may be expensive.
The time required for FDA and other clearances or approvals is uncertain and typically takes a number of years,
depending on the complexity and novelty of the product. Our analysis of data obtained from preclinical and
clinical activities is subject to confirmation and interpretation by regulatory authorities, which could delay, limit
or prevent regulatory approval. Any delay in obtaining or failure to obtain required clearance or approvals could
materially adversely affect our ability to generate revenues from the affected product. We have only limited
experience in filing and prosecuting applications necessary to gain regulatory approvals.

We are also subject to numerous foreign regulatory requirements governing the design and conduct of the

clinical trials and the manufacturing and marketing of our future products. The approval procedure varies among
countries. The time required to obtain foreign approvals often differs from that required to obtain FDA approvals.
Moreover, approval by the FDA does not ensure approval by regulatory authorities in other countries (or vice
versa).

All of the foregoing regulatory risks also are applicable to development, manufacturing and marketing

undertaken by our collaborative partners or other third parties.

Even if we obtain marketing approval, our therapeutic products will be subject to ongoing regulatory
review, which may be expensive and may affect our ability to successfully commercialize our products.

Even if we or our collaborative partners receive regulatory approval of a product, such approval may be

subject to limitations on the indicated uses for which the product may be marketed, which may limit the size of
the market for the product or contain requirements for costly post-marketing follow-up studies. The
manufacturers of our products for which we or our collaborative partners have obtained marketing approval will
be subject to continued review and periodic inspections by the FDA and other regulatory authorities. The

12

subsequent discovery of previously unknown problems with the product, clinical trial subjects, or with a
manufacturer or facility may result in restrictions on the product or manufacturer, including withdrawal of the
product from the market.

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

If we are unable to obtain, maintain and enforce patents or regulatory exclusivity (orphan drug or new
chemical entity exclusivity) for our products, we may not be able to succeed commercially.

We endeavor to obtain and maintain patent and trade secret protection for our products and processes when

available in order to protect them from unauthorized use and to produce a financial return consistent with the
significant time and expense required to bring our products to market. Our success will depend, in part, on our
ability to:

•

•

•

•

obtain and maintain patent protection for our products and manufacturing processes;

preserve our trade secrets;

operate without infringing the proprietary rights of third parties; and

secure licenses from others on acceptable terms.

We cannot be sure that any patent applications relating to our products that we will file in the future or that

any currently pending applications will issue on a timely basis, if ever. Since patent applications in the United
States filed prior to November 2000 are maintained in secrecy until patents issue and since publication of
discoveries in the scientific or patent literature often lag behind actual discoveries, we cannot be certain that we
were the first to make the inventions covered by each of our pending patent applications or that we were the first
to file patent applications for such inventions. Even if patents are issued, the degree of protection afforded by
such patents will depend upon the:

•

•

•

scope of the patent claims;

validity and enforceability of the claims obtained in such patents; and

our willingness and financial ability to enforce and/or defend them.

The patent position of biotechnology and pharmaceutical firms is often highly uncertain and usually

involves complex legal and scientific questions. Moreover, no consistent policy has emerged in the United States
or in many other countries regarding the breadth of claims allowed in biotechnology patents. Patents which may
be granted to us in certain foreign countries may be subject to opposition proceedings brought by third parties or
result in suits by us, which may be costly and result in adverse consequences for us.

In some cases, litigation or other proceedings may be necessary to assert claims of infringement, to enforce

patents issued to us or our licensors, to protect trade secrets, know-how or other intellectual property rights we
own or to determine the scope and validity of the proprietary rights of third parties. Such litigation could result in
substantial cost to us and diversion of our resources. An adverse outcome in any such litigation or proceeding
could have a material adverse effect on our business, financial condition and results of operations.

If our competitors prepare and file patent applications in the United States that claim technology also
claimed by us, we may be required to participate in interference proceedings declared by the U.S. Patent and
Trademark Office to determine priority of invention, which would result in substantial costs to us.

13

Since some of our U.S. patents covering recombinant Protein A have expired, we may face increased
competition which could harm our results of operations, financial condition, cash flow and future
prospects.

Other companies could begin manufacturing and selling recombinant Protein A in the U.S. and may directly

compete with us on certain Protein A products. This may induce us to sell Protein A at lower prices and may
erode our market share which could adversely affect our results of operations, financial condition, cash flow and
future prospects.

Our freedom to develop our product candidates may be challenged by others and we may have to engage
in litigation to determine the scope and validity of competitors’ patents and proprietary rights, which, if
we do not prevail, could harm our business, results of operations, financial condition, cash flow and future
prospects.

There has been substantial litigation and other proceedings regarding the complex patent and other
intellectual property rights in the pharmaceutical and biotechnology industries. We have been a party to, and in
the future may become a party to, patent litigation or other proceedings regarding intellectual property rights.

Other types of situations in which we may become involved in patent litigation or other intellectual property

proceedings include:

• We may initiate litigation or other proceedings against third parties to seek to invalidate the patents
held by such third parties or to obtain a judgment that our products or services do not infringe such
third parties’ patents.

• We may initiate litigation or other proceedings against third parties to seek to enforce our patents

against infringement.

•

•

If our competitors file patent applications that claim technology also claimed by us, we may participate
in interference or opposition proceedings to determine the priority of invention.

If third parties initiate litigation claiming that our processes or products infringe their patent or other
intellectual property rights, we will need to defend against such claims.

The cost to us of any patent litigation or other proceeding, even if resolved in our favor, could be
substantial. Some of our competitors may be able to sustain the cost of such litigation or proceedings more
effectively than we can because of their substantially greater financial resources. If a patent litigation or other
intellectual property proceeding is resolved unfavorably to us, we or our collaborative partners may be enjoined
from manufacturing or selling our products and services without a license from the other party and be held liable
for significant damages. The failure to obtain any required license on commercially acceptable terms or at all
may harm our business, results of operations, financial condition, cash flow and future prospects.

Uncertainties resulting from the initiation and continuation of patent litigation or other proceedings could

have a material adverse effect on our ability to compete in the marketplace. Patent litigation and other
proceedings may also absorb significant management time, attention and resources.

For more information about the legal proceedings in which we were involved but which have been settled,

please see “Legal Proceedings.”

We may become involved in litigation or other proceedings with collaborative partners, which may be time
consuming, costly and could result in delays in our development and commercialization efforts.

We conduct some of our development activities, and conduct most of our commercialization activities,

through collaborations with collaborative partners. Therefore, any disputes with such partners that lead to

14

litigation or similar proceedings may result in us incurring legal expenses, as well as facing potential legal
liability. Such disputes, litigation or other proceedings are also time consuming and may cause delays in our
development and commercialization efforts.

We have limited sales and marketing experience and capabilities.

We have limited sales, marketing and distribution experience and capabilities. We may, in some instances,

rely significantly on sales, marketing and distribution arrangements with our collaborative partners and other
third parties. In these instances, our future revenues will be materially dependent upon the success of the efforts
of these third parties.

If in the future we determine to perform sales, marketing and distribution functions ourselves, we would

face a number of additional risks, including:

•

•

•

we may not be able to attract and build a significant marketing staff or sales force;

the cost of establishing a marketing staff or sales force may not be justifiable in light of any product
revenues; and

our direct sales and marketing efforts may not be successful.

We have limited pharmaceutical manufacturing capabilities and will be dependent on third party
manufacturers.

We have limited pharmaceutical manufacturing experience and no commercial or pilot scale manufacturing

facilities for the production of pharmaceuticals. In order to continue to develop pharmaceutical products, apply
for regulatory approvals and, ultimately, commercialize any products, we may need to develop, contract for, or
otherwise arrange for the necessary manufacturing capabilities.

We currently rely upon third parties to produce material for preclinical and clinical testing purposes and
expect to continue to do so in the future. We also expect to rely upon third parties, including our collaborative
partners, to produce materials required for the commercial production of certain of our products if we succeed in
obtaining the necessary regulatory approvals. We believe that there is no proprietary aspect to the manufacture of
our product candidates. However, there are only a limited number of manufacturers that operate under the FDA’s
regulations for good manufacturing practices which are capable of and/or approved to manufacture our product
candidates. Timing for the initiation of new manufacturers is uncertain, and, if we are unable to arrange for third
party manufacturing of our product candidates on a timely basis, or to do so on commercially reasonable terms,
we may not be able to complete development of our product candidates or market them, if they are approved.

The manufacture of products by us and our collaborative partners and suppliers is subject to regulation by

the FDA and comparable agencies in foreign countries. Delay in complying or failure to comply with such
manufacturing requirements could materially adversely affect the marketing of our products.

If we are unable to continue to hire and retain skilled personnel, then we will have trouble developing and
marketing our products.

Our success depends largely upon the continued service of our management and scientific staff and our
ability to attract, retain and motivate highly skilled technical, scientific, management, regulatory, clinical and
marketing personnel. Potential employees with an expertise in the field of molecular biology, biochemistry,
regulatory affairs and/or clinical development of new drug and biopharmaceutical manufacturing are not
generally available in the market and are difficult to attract and retain. We also face significant competition for
such personnel from other companies, research and academic institutions, government and other organizations
who have superior funding and resources to be able to attract such personnel. The loss of key personnel or our

15

inability to hire and retain personnel who have technical, scientific or regulatory compliance backgrounds could
materially adversely affect our product development efforts and our business.

The market may not be receptive to our products upon their introduction.

The commercial success of our therapeutic products that are approved for marketing will depend upon their

acceptance by the medical community and third party payors as being clinically useful, cost effective and safe.
All of the products that we are developing are based upon new technologies or therapeutic approaches. As a
result, it is hard to predict market acceptance of our products.

Other factors that we believe will materially affect market acceptance of our products and services include:

•

•

•

•

•

the timing of receipt of marketing approvals and the countries in which such approvals are obtained;

the safety, efficacy and ease of administration of our products;

the success of physician education programs;

the availability of government and third party payor reimbursement of our products; and

competition from products which may offer better safety, efficacy or lower cost.

Healthcare reform measures could adversely affect our business.

The efforts of governmental and third-party payors to contain or reduce the costs of healthcare may

adversely affect the business and financial condition of pharmaceutical and biotechnology companies.
Specifically, in both the United States and some foreign jurisdictions, there have been a number of legislative and
regulatory proposals to change the health care system in ways that could affect our ability to sell our products
profitably. The U.S. Congress has just passed the America Affordable Health Choices Act of 2009 and is
considering a number of proposals that are intended to reduce or limit the growth of health care costs and which
could significantly transform the market for pharmaceuticals products. We expect further federal and state
proposals and health care reforms to continue to be proposed by legislators, which could limit the prices that can
be charged for the products we develop and may limit our commercial opportunity. In the United States, the
Medicare Prescription Drug, Improvement, and Modernization Act of 2003, also called the Medicare
Modernization Act, or MMA, changed the way Medicare covers and pays for pharmaceutical products. These
cost reduction initiatives and other provisions of this legislation could decrease the coverage and price that we
receive for any approved products and could seriously harm our business. While the MMA applies only to drug
benefits for Medicare beneficiaries, private payors often follow Medicare coverage policy and payment
limitations in setting their own reimbursement rates, and any reduction in reimbursement that results from the
MMA may result in a similar reduction in payments from private payors. The continuing efforts of government
and other third-party payors to contain or reduce the costs of health care through various means may limit our
commercial opportunity. In addition, the pendency or approval of such proposals could result in a decrease in the
price of Repligen’s common stock or limit our ability to raise capital or to enter into collaborations or license
rights to our products.

We compete with pharmaceutical and biotechnology companies who are capable of developing new
approaches that could make our products and technology obsolete.

The market for therapeutic and commercial products is intensely competitive, rapidly evolving and subject

to rapid technological change. Pharmaceutical and biotechnology companies may have substantially greater
financial, manufacturing, marketing, and research and development resources than we have. New approaches by
these competitors may make our products and technologies obsolete or noncompetitive.

16

We have incurred substantial losses, we may continue to incur operating losses and we will not be
successful until we reverse this trend.

Although the company had significant net income in fiscal years 2009 and 2008 as a result of the ImClone

and Bristol settlements, we have historically incurred operating losses since our founding in 1981. We incurred a
loss for fiscal 2010 and we expect to incur operating losses for the foreseeable future.

While we generate revenue from bioprocessing product sales and began receiving royalty payments in fiscal

year 2009 from Bristol for the net sales of their Orencia® product in the United States, this revenue may not be
sufficient to cover the costs of our clinical trials and drug development programs. We plan to continue to invest
in key research and development activities. As a result, we will need to generate significant revenues in order to
achieve profitability. We cannot be certain whether or when this will occur because of the significant
uncertainties that affect our business.

We may need to obtain additional capital resources for our drug development programs, or we may be
unable to develop or discover new drugs.

We may need additional long-term financing to develop our drug development programs through the
clinical trial process as required by the FDA and to develop our commercial products business. We also may
need additional long-term financing to support future operations and capital expenditures, including capital for
additional personnel and facilities. If we spend more money than currently expected for our drug development
programs and our commercial products business, we may need to raise additional capital by selling debt or equity
securities, by entering into strategic relationships or through other arrangements. We may be unable to raise any
additional amounts on reasonable terms or when they are needed due to the volatile nature of the biotechnology
marketplace. If we are unable to raise this additional capital, we may have to delay or postpone critical clinical
studies or abandon other development programs.

Our stock price could be volatile, which could cause you to lose part or all of your investment.

The market price of our common stock, like that of the common stock of many other development stage
biotechnology companies, is highly volatile. In addition, the stock market has experienced extreme price and
volume fluctuations. This volatility has significantly affected the market prices of securities of many
biotechnology and pharmaceutical companies for reasons frequently unrelated to or disproportionate to the
operating performance of the specific companies. These broad market fluctuations may adversely affect the
market price of our common stock.

Provisions in our certificate of incorporation and by-laws and of Delaware law may prevent or delay an
acquisition of our Company, which could decrease the trading price of our common stock.

Our certificate of incorporation, by-laws and Delaware law contain provisions that are intended to deter

coercive takeover practices and inadequate takeover bids by making such practices or bids unacceptably
expensive to the raider and to encourage prospective acquirors to negotiate with our Board of Directors rather
than to attempt a hostile takeover. These provisions include our Board of Directors’ ability to issue preferred
stock without stockholder approval and Delaware law’s various restrictions on mergers and other business
combinations between us and any holder of 15% or more of our outstanding common stock. In addition, we
maintain a shareholder rights plan which may deter a potential acquiror from pursuing an offer for our company.

We believe these provisions protect our stockholders from coercive or otherwise unfair takeover tactics by

requiring potential acquirors to negotiate with our Board of Directors and by providing our Board of Directors
with more time to assess any acquisition proposal. These provisions are not intended to make our company
immune from takeovers. However, these provisions apply even if the offer may be considered beneficial by some
stockholders and could delay or prevent an acquisition that our Board of Directors determines is not in the best
interests of our company and our stockholders.

17

Item 1B. UNRESOLVED STAFF COMMENTS

None.

Item 2.

PROPERTIES

We lease approximately 25,000 square feet of space located in Waltham, Massachusetts which serves as our

corporate headquarters. We also conduct manufacturing, research and development, marketing and
administrative operations at this facility. In addition, we lease approximately 10,000 square feet of space at a
second location in Waltham for expanded manufacturing and administrative operations. Both of these leases
expire in 2012. During fiscal 2010, we incurred total rental costs for both facilities of approximately $689,000.

Item 3.

LEGAL PROCEEDINGS

ImClone Systems

In May 2004, Repligen and the Massachusetts Institute of Technology (“MIT”) filed an action in the United

States District Court for the District of Massachusetts against ImClone Systems, Incorporated (“ImClone”) for
infringement of U.S. Patent No. 4,663,281 (the “‘281 patent”) based on ImClone’s manufacture and sale of
Erbitux®. The ‘281 patent, which covers the use of certain genetic elements that increase protein production in a
mammalian cell, is assigned to MIT and exclusively licensed to Repligen.

On September 10, 2007, the Company and MIT entered into a settlement agreement (the “ImClone

Settlement”) with ImClone relating to the lawsuit against ImClone for infringement of the ‘281 patent. Pursuant
to the ImClone Settlement, ImClone made a payment of $65 million to Repligen and MIT that resulted in net
proceeds to Repligen of $40.17 million, as follows:

Gross proceeds from ImClone Settlement agreement . . . . . . . . . . . . . . . . . . .
Less: Amounts paid to MIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Less: Legal fees and other costs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$ 65,000,000
(11,000,000)
(13,830,000)

Net gain on litigation settlement

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$ 40,170,000

The ImClone Settlement served as the basis for the Company and MIT to dismiss the lawsuit against
ImClone and for the Company to grant ImClone a non-exclusive sublicense to the ‘281 patent and certain other
intellectual property. There are no further obligations to the Company with respect to the sublicenses. The net
gain on the litigation settlement was recorded as a separate component of operating expenses in the Company’s
statement of operations in fiscal 2008.

Bristol-Myers Squibb Company

In January 2006, Repligen and the University of Michigan jointly filed a complaint against Bristol in the

United States District Court for the Eastern District of Texas for infringement of U.S. Patent No. 6,685,941 (the
“‘941 patent”) for the commercial sale of Orencia®. The ‘941 patent, entitled “Methods of Treating Autoimmune
Disease via CTLA4-Ig,” covers methods of using CTLA4-Ig to treat rheumatoid arthritis, as well as other
therapeutic methods. Repligen has exclusive rights to this patent from its owners, the University of Michigan and
the U.S. Navy. In February 2006, Bristol answered the complaint and counterclaimed seeking a declaratory
judgment that the ‘941 patent is invalid and unenforceable and that Bristol does not infringe the patent.

On April 7, 2008, Repligen and the University of Michigan entered into a settlement agreement (the “Bristol

Settlement”) with Bristol relating to the lawsuit against Bristol for infringement of the ‘941 patent. Pursuant to
the Bristol Settlement, Bristol made an initial payment of $5 million to Repligen. The Bristol Settlement further
provides for Bristol to pay royalties on the United States net sales of Orencia® for any clinical indication at a rate
of 1.8% for the first $500 million of annual net sales, 2.0% for the next $500 million of annual net sales and 4%

18

of annual net sales in excess of $1 billion for each year from January 1, 2008 until December 31, 2013. The
Bristol Settlement served as the basis for Repligen and the University of Michigan to dismiss the lawsuit against
Bristol and for Repligen and the University of Michigan to grant to Bristol an exclusive license to the ‘941 patent
and certain other intellectual property. Repligen has no continuing obligations to Bristol as a result of this
settlement. Pursuant to the Bristol Settlement, Repligen has recognized $8,980,000 and $13,383,000 in fiscal
years 2010 and 2009, respectively. The $9.0 million recognized in fiscal year 2010 was for sales of Orencia®
from January 1, 2009 through December 31, 2009. The $13.4 million recognized in fiscal year 2009 was
comprised of a $5 million initial payment, $1.3 million for sales of Orencia® from January 1, 2008 through
December 31, 2008, and $7.1 million for sales in fiscal year 2009 (see Note 2).

Repligen must also remit to the University of Michigan 15% of all royalty revenue received from Bristol,

after deducting certain legal and other costs incurred related to the Bristol Settlement. Repligen incurred
approximately $6.1 million in such legal costs. Royalty expense for fiscal years 2010 and 2009 was $1,347,000
and $1,091,000, respectively. This operating expense has been included on the statements of operations under the
line item “Cost of royalty and other revenue.”

Other

From time to time, we may be subject to other legal proceedings and claims in the ordinary course of
business. We are not currently aware of any such proceedings or claims that we believe will have, individually or
in the aggregate, a material adverse effect on our business, financial condition or results of operations.

Item 4.

(REMOVED AND RESERVED)

19

PART II

Item 5. MARKET FOR REGISTRANT’S COMMON EQUITY, RELATED STOCKHOLDER

MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES

Market Information

Our common stock is traded on the Nasdaq Global Market under the symbol “RGEN.” The quarterly high

and low closing prices for our common stock are shown in the following table.

Fiscal Year 2010 Fiscal Year 2009

High

Low

High

Low

First Quarter
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Second Quarter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Third Quarter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fourth Quarter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$5.50
$5.55
$5.13
$4.06

$3.92
$4.96
$3.74
$3.35

$6.23
$5.58
$4.78
$4.79

$4.72
$4.51
$3.30
$3.56

Stockholders and Dividends

As of June 2, 2010, there were approximately 666 stockholders of record of our common stock. We have not

paid any dividends since our inception and do not intend to pay any dividends on our common stock in the
foreseeable future. We anticipate that we will retain all earnings, if any, to support our operations and our
proprietary drug development programs. Any future determination as to the payment of dividends will be at the
sole discretion of our board of directors and will depend on our financial condition, results of operations, capital
requirements and other factors our board of directors deems relevant.

Equity Compensation Plan Information

See Part III, Item 12 for information regarding securities authorized for issuance under our equity

compensation plans.

Issuer Purchases of Equity Securities

In June 2008, the Board of Directors authorized a program to repurchase up to 1.25 million shares of our

common stock to be repurchased at the discretion of management from time to time in the open market or
through privately negotiated transactions. The repurchase program has no set expiration date and may be
suspended or discontinued at any time. For the twelve-month period ended March 31, 2009, the Company
repurchased 492,827 shares of common stock, for an aggregate purchase price of $1,969,240, leaving 757,173
shares remaining under this authorization.

20

COMPARISON OF 5 YEAR CUMULATIVE TOTAL RETURN*
Among Repligen Corporation, the NASDAQ Composite Index
and the NASDAQ Pharmaceutical Index

$300

$250

$200

$150

$100

$50

$0

3/05

3/06

3/07

3/08

3/09

3/10

Repligen Corporation

NASDAQ Composite

NASDAQ Pharmaceutical

*$100 invested on 3/31/05 in stock or index, including reinvestment of dividends.
Fiscal year ending March 31.

The information contained in the performance graph shall not be deemed to be “soliciting material” or to be

“filed” with the Securities and Exchange Commission, and such information shall not be incorporated by
reference into any future filing under the Securities Act or Exchange Act, except to the extent that Repligen
specifically incorporates it by reference into such filing.

21

Item 6.

SELECTED FINANCIAL DATA

The following selected financial data are derived from the audited financial statements of Repligen. The
selected financial data set forth below should be read in conjunction with our financial statements and the related
notes thereto and “Management’s Discussion and Analysis of Financial Condition and Results of Operations”
included elsewhere in this report and our Annual Report on Form 10-K for the years ended March 31, 2009,
2008, 2007 and 2006.

Years ended March 31,

2010

2009

2008

2007

2006

(In thousands except per share amounts)

Revenue:

Product revenue . . . . . . . . . . . . . . . . . . . . . . .
Royalty and other revenue . . . . . . . . . . . . . . .

$ 10,305
10,666

$ 14,529
14,833

$ 18,587
709

$ 13,074
1,000

$ 12,529
382

Total revenue . . . . . . . . . . . . . . . . . . . . .

20,971

29,362

19,296

14,074

12,911

Operating expenses:

Cost of product revenue . . . . . . . . . . . . . . . . .
Cost of royalty and other revenue . . . . . . . . .
Research and development
. . . . . . . . . . . . . .
Selling, general and administrative . . . . . . . .
. . . . . . . .
Net gain from litigation settlement

Total operating expenses . . . . . . . . . . . .
(Loss) income from operations . . . . . . . . . . .

Interest expense . . . . . . . . . . . . . . . . . . . . . . . . . . .
Investment income . . . . . . . . . . . . . . . . . . . . . . . . .
Other income . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

(Loss) income before taxes . . . . . . . . . . . . . . . . . .
Income tax (benefit) provision . . . . . . . . . . . . . . .

Net (loss) income . . . . . . . . . . . . . . . . . . . . . . . . . .

Earnings per share:

Basic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Diluted . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Weighted average shares outstanding:

Basic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Diluted . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$

$

$

4,159
1,347
14,160
7,072
—

26,738
(5,767)

(2)
870
—

(4,899)
(835)

5,686
1,091
12,772
5,933
—

25,482
3,880

(3)
1,896
—

5,773
27

6,160
—
7,241
10,173
(40,170)

(16,596)
35,892

(9)
2,051
—

37,934
827

3,615
—
5,924
6,360
—

15,899
(1,825)

(11)
947
—

(889)
—

(4,064) $

5,746

$ 37,107

$

(889) $

(0.13) $

(0.13) $

0.19

0.18

$

$

1.20

1.18

$

$

(0.03) $

(0.03) $

3,551
—
5,163
5,417
—

14,131
(1,220)

(3)
750
1,170

697
—

697

0.02

0.02

30,752

30,752

30,958

31,290

30,834

31,321

30,379

30,379

30,125

30,691

2010

2009

2008

2007

2006

As of March 31,

(In thousands)

Balance Sheet Data:
Cash and marketable securities (1) . . . . . . . . . . . .
Working capital . . . . . . . . . . . . . . . . . . . . . . . . . . .
Total assets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Long-term obligations . . . . . . . . . . . . . . . . . . . . . .
Accumulated deficit . . . . . . . . . . . . . . . . . . . . . . . .
Stockholders’ equity . . . . . . . . . . . . . . . . . . . . . . .

$ 59,146
55,024
71,420
642
(117,921)
66,120

$ 63,961
50,235
73,755
82
(113,857)
69,123

$ 60,589
49,831
68,840
143
(120,577)
64,107

$ 22,627
22,394
29,076
200
(157,683)
25,538

$ 23,408
18,575
28,599
231
(156,794)
25,433

(1) Excludes restricted cash of $200 related to our headquarters’ lease arrangement for all years presented.

22

Item 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND

RESULTS OF OPERATIONS

This annual report on Form 10-K contains forward-looking statements which are made pursuant to the safe

harbor provisions of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities
Exchange Act of 1934, as amended (the “Exchange Act”). The forward-looking statements in this annual report
on Form 10-K do not constitute guarantees of future performance. Investors are cautioned that statements in this
annual report on Form 10-K that are not strictly historical statements, including, without limitation, statements
regarding current or future financial performance, potential impairment of future earnings, management’s
strategy, plans and objectives for future operations and product candidate acquisition, clinical trials and results,
litigation strategy, product research and development, selling, general and administrative expenditures,
intellectual property, development and manufacturing plans, availability of materials and product and adequacy
of capital resources and financing plans constitute forward-looking statements. Such forward-looking statements
are subject to a number of risks and uncertainties that could cause actual results to differ materially from those
anticipated, including, without limitation, the risks identified under the caption “Risk Factors” and other risks
detailed in this annual report on Form 10-K and our other filings with the Securities and Exchange Commission.
We assume no obligation to update any forward-looking information contained in this annual report on Form
10-K.

Overview

We are a biopharmaceutical company focused on the development and commercialization of innovative

therapies that harness biological pathways and deliver value to patients and clinicians in neurology,
gastroenterology and orphan diseases. We are currently conducting a number of drug development programs for
diseases such as pancreatitis, bipolar disorder, Friedreich’s ataxia and spinal muscular atrophy. We also have a
bioprocessing business that focuses on the development and commercialization of products that are used for the
production of biopharmaceuticals. In addition, we receive royalties from Bristol-Myers Squibb Company
(“Bristol”) on their net sales in the United States of their product Orencia®. Total revenue in fiscal 2010
decreased significantly as compared to fiscal 2009 due to a decrease in our bioprocessing product sales as we
experienced lower customer demand for our Protein A products due to the current economic environment and a
one-time royalty payment from Bristol recognized as revenue in the prior year. We seek to invest the profits from
our current commercial products and royalty and other revenues, as well as use our existing financial resources,
to advance the development of our therapeutic product candidates and our bioprocessing business.

CRITICAL ACCOUNTING POLICIES AND ESTIMATES

While our significant accounting polices are more fully described in the notes to our financial statements,
we have identified the policies and estimates below as critical to our business operations and the understanding
of our results of operations. The impact of and any associated risks related to these policies on our business
operations are discussed throughout “Management’s Discussion and Analysis of Financial Condition” and
“Results of Operations” where such policies affect our reported and expected financial results.

Revenue recognition

We generate product revenues from the sale of bioprocessing products to customers in the pharmaceutical

and process chromatography industries. We recognize revenue related to product sales upon delivery of the
product to the customer as long as there is persuasive evidence of an arrangement, the sales price is fixed or
determinable and collection of the related receivable is reasonably assured. Determination of whether these
criteria have been met are based on management’s judgments primarily regarding the fixed nature of the fee
charged for product delivered, and the collectability of those fees. We have a few longstanding customers who
comprise the majority of revenue and have excellent payment history and therefore we do not require collateral.
We have had no significant write-offs of uncollectible invoices in the periods presented.

23

At the time of sale, we also evaluate the need to accrue for warranty and sales returns. The supply
agreements we have with our customers and related purchase orders identify the terms and conditions of each
sale and the price of the goods ordered. Due to the nature of the sales arrangements, inventory produced for sale
is tested for quality specifications prior to shipment. Since the product is manufactured to order and in
compliance with required specifications prior to shipment, the likelihood of sales return, warranty or other issues
is largely diminished. Sales returns and warranty issues are infrequent and have had nominal impact on our
financial statements historically.

In April 2008, we settled our outstanding litigation with Bristol and began recognizing royalty revenue in

fiscal year 2009 for Bristol’s net sales in the United States of Orencia® which is used in the treatment of
rheumatoid arthritis. Pursuant to the Bristol Settlement, we recognized $13,383,000 in royalty revenue in fiscal
2009, which included a $5.0 million initial payment and $1.3 million for sales of Orencia® prior to fiscal 2009, in
addition to royalties earned on sales of Orencia® during our fiscal 2009. We recognized $8,980,000 in royalty
revenue for sales of Orencia® in fiscal 2010. Revenue earned from Bristol royalties is recorded in the periods
when it is earned based on royalty reports sent by Bristol to us. We have no continuing obligations to Bristol as a
result of this settlement.

Additionally, during fiscal years 2010, 2009 and 2008, we earned and recognized approximately

$1,009,000, $776,000 and $244,000, respectively in royalty revenue from ChiRhoClin for their sales of secretin.
Revenue earned from ChiRhoClin royalties is recorded in the periods when it is earned based on royalty reports
sent by ChiRhoClin to us. As of December 31, 2009, ChiRhoClin has fulfilled its royalty obligations to us for its
sales of secretin. We do not expect to recognize any further royalty revenue from ChiRhoClin.

In fiscal 2010, we recognized $552,000 and $125,000 of revenue from sponsored research and development
projects under agreements with the Muscular Dystrophy Association (“MDA”) and jointly with the Friedreich’s
Ataxia Research Alliance and the National Ataxia Foundation, respectively. During fiscal 2009, we recognized
approximately $564,000 and $110,000 of revenue from sponsored research and development projects under
agreements with the Muscular Dystrophy Association (“MDA”) and Comitato RUDI onlus—GoFAR
(“GoFAR”), respectively. During the fiscal year ended March 31, 2008, we recognized $365,000 of revenue from
a sponsored research and development project under an agreement with the Stanley Medical Research Institute.

Research revenue is recognized when the expense has been incurred and services have been performed.
Determination of which incurred costs qualify for reimbursement under the terms of our contractual agreements
and the timing of when such costs were incurred involves the judgment of management. Our calculations are
based upon the agreed-upon terms as stated in the arrangements. However, should the estimated calculations
change or be challenged by other parties to the agreements, research revenue may be adjusted in subsequent
periods. The calculations have not historically changed or been challenged and we do not anticipate any
subsequent change in revenue related to sponsored research and development projects.

There have been no material changes to our initial estimates related to revenue recognition in any periods

presented in the accompanying financial statements.

Inventories

Inventories relate to our bioprocessing business. We value inventory at cost or, if lower, fair market value
using the first-in, first-out method. We review our inventory at least quarterly and record a provision for excess
and obsolete inventory based on our estimates of expected sales volume, production capacity and expiration dates
of raw materials, work-in process and finished products. Expected sales volumes are determined based on supply
forecasts provided by key customers for the next three to twelve months. We write down inventory that has
become obsolete, inventory that has a cost basis in excess of its expected net realizable value, and inventory in
excess of expected requirements to cost of product revenue. Manufacturing of bioprocessing finished goods is
done to order and tested for quality specifications prior to shipment.

24

A change in the estimated timing or amount of demand for our products could result in additional provisions

for excess inventory quantities on hand. Any significant unanticipated changes in demand or unexpected quality
failures could have a significant impact on the value of inventory and reported operating results. During all
periods presented in the accompanying financial statements, there have been no material adjustments related to a
revised estimate of inventory valuations.

Business Combinations

Amounts paid for acquisitions are allocated to the assets acquired and liabilities assumed, if any, based on

their fair values at the dates of acquisition. The fair value of identifiable intangible assets is based on detailed
valuations that use information and assumptions determined by management. Any excess of purchase price over
the fair value of the net tangible and intangible assets acquired is allocated to goodwill. The fair value of
contingent consideration includes estimates and judgments made by management regarding the extent of
royalties to be earned in excess of the defined minimum royalties. Management will update these estimates and
the related fair value of contingent consideration at each reporting period.

Accrued liabilities

We estimate accrued liabilities by identifying services performed on our behalf, estimating the level of

service performed and determining the associated cost incurred for such service as of each balance sheet date.
Examples of estimated accrued expenses include:

•

•

•

Fees paid to contract manufacturers in conjunction with the production of clinical materials. These
expenses are normally determined through a contract or purchase order issued by us;

Service fees paid to organizations for their performance in conducting clinical trials. These expenses
are determined by contracts in place for those services and communications with project managers on
costs which have been incurred as of each reporting date;

Professional and consulting fees incurred with law firms, audit and accounting service providers and
other third party consultants. These expenses are determined by either requesting those service
providers to estimate unbilled services at each reporting date for services incurred, or tracking costs
incurred by service providers under fixed fee arrangements.

We have processes in place to estimate the appropriate amounts to record for accrued liabilities, which
principally involve the applicable personnel reviewing the services provided. In the event that we do not identify
certain costs which have begun to be incurred or we under or over-estimate the level of services performed or the
costs of such services, the reported expenses for that period may be too low or too high. The date on which
certain services commence, the level of services performed on or before a given date, and the cost of such
services are often judgmental. We make these judgments based upon the facts and circumstances known at the
date of the financial statements.

A change in the estimated cost or volume of services provided could result in additional accrued liabilities.

Any significant unanticipated changes in such estimates could have a significant impact on our accrued liabilities
and reported operating results. There have been no material adjustments to our accrued liabilities in any of the
periods presented in the accompanying financial statements.

Stock-based compensation

We use the Black-Scholes option pricing model to calculate the fair value of share-based awards on the

grant date.

The expected term of options granted represents the period of time for which the options are expected to be

outstanding and is derived from our historical stock option exercise experience and option expiration data. The

25

expected life of stock options granted is based on the simplified method. Accordingly, the expected term is
presumed to be the midpoint between the vesting date and the end of the contractual term. In addition, for
purposes of estimating the expected term, we have aggregated all individual option awards into one group as we
do not expect substantial differences in exercise behavior among its employees. The expected volatility is a
measure of the amount by which our stock price is expected to fluctuate during the expected term of options
granted. We determined the expected volatility based upon the historical volatility of our common stock over a
period commensurate with the option’s expected term, exclusive of any events not reasonably anticipated to recur
over the option’s expected term. The risk-free interest rate is the implied yield available on U.S. Treasury zero-
coupon issues with a remaining term equal to the option’s expected term on the grant date. We have never
declared or paid any cash dividends on any of our capital stock and do not expect to do so in the foreseeable
future. Accordingly, we use an expected dividend yield of zero to calculate the grant-date fair value of a stock
option.

We recognize compensation expense on a straight-line basis over the requisite service period based upon
options that are ultimately expected to vest, and accordingly, such compensation expense has been adjusted by an
amount of estimated forfeitures. Forfeitures represent only the unvested portion of a surrendered
option. Forfeitures are estimated at the time of grant and revised, if necessary, in subsequent periods if actual
forfeitures differ from those estimates. Based on an analysis of historical data, we have calculated an 8% annual
forfeiture rate for non-executive level employees, a 3% annual forfeiture rate for executive level employees, and
a 0% forfeiture rate for non-employee members of the Board of Directors, which we believe is a reasonable
assumption to estimate forfeitures. However, the estimation of forfeitures requires significant judgment, and to
the extent actual results or updated estimates differ from our current estimates, such amounts will be recorded as
a cumulative adjustment in the period estimates are revised.

For the years ended March 31, 2010, 2009 and 2008, we recorded stock-based compensation expense of
approximately $1,007,000, $823,000 and $524,000, respectively, for stock options granted under the Second
Amended and Restated 2001 Repligen Corporation Stock Plan (the “2001 Plan”).

As of March 31, 2010, there was $1,919,119 of total unrecognized compensation cost related to unvested

share-based awards. This cost is expected to be recognized over a weighted average remaining requisite service
period of 3.11 years. We expect 823,294 in unvested options to vest over the next five years.

RESULTS OF OPERATIONS

The following discussion of the financial condition and results of operations should be read in conjunction

with the accompanying financial statements and the related footnotes thereto.

Revenues

Total revenues for fiscal 2010, 2009 and 2008 were $20,971,000, $29,362,000, and $19,296,000,
respectively, and were primarily comprised of sales of our bioprocessing products and royalties. Our total
revenue was comprised of:

Year ended March 31,

% Change

2010

2009

2008

2010 vs. 2009

2009 vs. 2008

Bioprocessing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SecreFlo® . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

(in thousands, except percentages)
$16,321
$14,361
$10,305
2,266
168
—

Product revenue . . . . . . . . . . . . . . . . . . . . . . . . . .
Royalty and other revenue . . . . . . . . . . . . . . . . . . . . . .

$10,305
10,666

$14,529
14,833

$18,587
709

Total revenue . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$20,971

$29,362

$19,296

(28%)
(100%)

(29%)
(28%)

(29%)

(12%)
(93%)

(22%)
1992%

52%

26

Substantially all of our bioprocessing products are based on recombinant Protein A and are sold to

customers who incorporate our manufactured products into their proprietary antibody purification systems to be
sold directly to the pharmaceutical industry. Monoclonal antibodies are a well-established class of drug with
applications in rheumatoid arthritis, asthma and a variety of cancers. Sales of our bioprocessing products are
therefore impacted by the timing of large-scale production orders and the regulatory approvals for such
antibodies, which may result in significant quarterly fluctuations.

During fiscal 2010, bioprocessing product sales decreased by $4,056,000 or 28% as compared to fiscal

2009. Volume decreased 26% due to decreased demand from certain key customers in reaction to current
economic conditions and other business events. Changes in the mix of products sold in fiscal 2010 as compared
to fiscal 2009 comprised the remaining 2% decrease. We sell various bioprocessing products at various price
points. The mix of products sold varies and impacts the fluctuations in total product revenue and cost of product
revenues from period to period.

During fiscal 2009, bioprocessing product sales decreased by $1,960,000 or 12% as compared to fiscal
2008. Volume decreased 5% due to decreased demand from certain key customers in reaction to the current
credit crisis and other business events. Changes in the mix of products sold in fiscal 2009 as compared to fiscal
2008 comprised the remaining 7% decrease.

We anticipate that bioprocessing product sales will increase in fiscal 2011 as our customers respond to an
anticipated economic recovery during the year. In addition, our bioprocessing product sales may be subject to
quarterly fluctuations due to the timing of large-scale production orders.

Sales of SecreFlo® decreased $2,098,000 in fiscal 2009 as we discontinued selling this product in the second

quarter of fiscal 2009. The settlement in fiscal 2005 with our sole supplier of SecreFlo®, ChiRhoClin, provided
for a certain amount of vials of product that we could ultimately ship. The final shipment of SecreFlo® to us from
ChiRhoClin was received in fiscal 2008 and we discontinued selling SecreFlo® in the second quarter of fiscal
2009.

Pursuant to the Bristol Settlement (as defined in Note 10), we recognized royalty revenue of approximately

$8,980,000 and $13,383,000 in fiscal years 2010 and 2009, respectively. The $13,383,000 recognized in fiscal
2009 included an initial $5.0 million royalty payment, $1.3 million in royalties for sales of Orencia® from
January 1, 2008 to March 31, 2008, as well as $7.1 million for sales in fiscal year 2009. For fiscal 2011, we
expect royalty revenues to increase moderately over fiscal 2010 as Bristol’s Orencia® continues to penetrate the
market.

Also, during fiscal years 2010, 2009 and 2008, we earned and recognized approximately $1,009,000,

$776,000 and $244,000, respectively, in royalty revenue from ChiRhoClin. As of December 31, 2009,
ChiRhoClin has fulfilled its royalty obligations to us for its sales of our secretin. We do not expect to recognize
any further royalty revenue from ChiRhoClin.

In fiscal 2010, we recognized $552,000 and $125,000 of revenue from sponsored research and development
projects under agreements with the Muscular Dystrophy Association (“MDA”) and jointly with the Friedreich’s
Ataxia Research Alliance and the National Ataxia Foundation, respectively. During fiscal 2009, we recognized
approximately $564,000 and $110,000 of revenue from sponsored research and development projects under
agreements with the MDA and Comitato RUDI onlus—GoFAR (“GoFAR”), respectively. During the fiscal year
ended March 31, 2008, we recognized $365,000 of revenue from a sponsored research and development project
under an agreement with the Stanley Medical Research Institute.

We expect research and license revenues will remain relatively consistent in fiscal 2011 as the MDA grant

related effort continues.

27

Costs and operating expenses

Total costs and operating expenses for fiscal 2010, 2009 and 2008 consist of the following:

Year ended March 31,

% Change

2010

2009

2008

2010 vs. 2009

2009 vs. 2008

(In thousands)
Costs and operating expenses:

Cost of product revenue . . . . . . . . . . . . . . . . . . .
Cost of royalty and other revenue . . . . . . . . . . . .
Research and development . . . . . . . . . . . . . . . . .
Selling, general and administrative . . . . . . . . . . .
Net gain from litigation settlement . . . . . . . . . . .

$ 4,159
1,347
14,160
7,072
—

$ 5,686
1,091
12,772
5,933
—

$ 6,160

—
7,241
10,173
(40,170)

Total costs and operating expenses . . . . . . .

$26,738

$25,482

$(16,596)

(27%)
23%
11%
19%
—

5%

(8%)

—
76%
(42%)
—

254%

The decrease in cost of product revenue of $1,527,000 or 27% in fiscal 2010 as compared to fiscal 2009 is

primarily due to a 29% decrease in bioprocessing product sales as well as favorable manufacturing variances.
This decrease is partially offset by higher depreciation costs of approximately $156,000 related to investments in
our manufacturing facilities.

The decrease in cost of product revenue of $474,000 or 8% in fiscal 2009 as compared to fiscal 2008 was
primarily due to a 12% decrease in bioprocessing sales. This decrease was partially offset by increased direct labor
costs of approximately $193,000 due primarily to additional quality assurance and control personnel hired to meet
growing customer demand for increased product quality assurance efforts and to support ISO 9001 certification. It
was also partially offset by higher depreciation and occupancy costs of approximately $357,000 primarily
associated with our manufacturing and administrative expansion at a second site located in Waltham, MA.

Pursuant to the Bristol Settlement, we must remit 15% of royalty revenue received through the expiration of

the agreement in December 2013, after deducting certain allowable legal and other costs, to the University of
Michigan. For fiscal 2010 and 2009, this cost of royalty revenue was approximately $1,347,000 and $1,091,000,
respectively. This increase is directly related to the increase in Bristol royalty revenue noted above.

Research and development costs primarily include costs of internal personnel, external pharmacology and

toxicology research, clinical trials and the costs associated with the manufacturing and testing of clinical
materials. We currently have ongoing clinically enabled research and development programs that support our
secretin and uridine product candidates. In addition, we are pursuing pre-clinical activities in Friedreich’s ataxia
and spinal muscular atrophy that may or may not be further developed. Due to the small size of the Company and
the fact that these various programs share personnel and fixed costs, we do not track all our expenses or allocate
any fixed costs by program, and therefore, have not provided an estimate of historical costs incurred by project.

Each of our therapeutic research and development programs is subject to risks and uncertainties, including
the requirement to seek regulatory approvals that are outside of our control. For example, our clinical trials may
be subject to delays based on our inability to enroll patients at the rate that we expect to meet the schedule for our
planned clinical trials. Moreover, the product candidates identified in these research programs, particularly in our
early stage programs must overcome significant technological, manufacturing and marketing challenges before
they can be successfully commercialized. For example, results from our preclinical animal models may not be
replicated in our clinical trials with humans. As a result of these risks and uncertainties, we are unable to predict
with any certainty the period in which material net cash inflows from such projects could be expected to
commence or the completion date of these programs.

These risks and uncertainties also prevent us from estimating with any certainty the specific timing and
future costs of our research and development programs, although historical trends within the industry suggest that

28

expenses tend to increase in later stages of development. Collaborations with commercial vendors and academic
researchers accounted for 51%, 59%, and 45% of our research and development expenses for fiscal 2010, 2009,
and 2008, respectively. The outsourcing of such services provides us flexibility to discontinue or increase
spending depending on the success of our research and development programs.

During fiscal 2010, research and development expenses increased by $1,388,000 or 11% as compared to

fiscal 2009. This increase is comprised primarily of 1) $909,000 related to our new DcpS program to develop a
drug for the treatment of patients with spinal muscular atrophy, 2) $891,000 related to Friedreich’s ataxia as we
identified a clinical candidate and began preparing for a phase 1 clinical trial and 3) $236,000 related to increased
personnel expenses primarily due to headcount additions in clinical and regulatory areas. These increases were
partially offset by a $746,000 decrease as we approached the end of our phase 3 clinical trial for RG1068,
evaluating the use of human secretin in aiding pancreatic imaging.

During fiscal 2009, research and development expenses increased by $5,531,000 or 76% as compared to
fiscal 2008. This increase was comprised primarily of 1) $1,869,000 related to the continued phase 3 clinical trial
for RG1068, evaluating the use of human secretin in pancreatic imaging, 2) $1,500,000 related to the phase 2b
clinical trial for RG2417, evaluating the use of uridine to treat bipolar depression and 3) $1,388,000 related to
Friedreich’s ataxia as we continued to search for a clinical candidate. Additionally, there were increased
personnel expenses of $724,000 primarily due to headcount additions in clinical, regulatory and research and
development areas.

Future research and development expenses are dependent on a number of variables, including the cost and

design of clinical trials and external costs such as manufacturing of clinical materials. We expect our research
and development expenses in fiscal 2011 to decrease moderately primarily due to the secretin clinical trial ending
in fiscal 2010, the timing of certain expenditures associated with our Friedreich’s ataxia program for which we
recently filed an IND application with the FDA, partially offset by increased spending on our DcpS program for
treatment of patients with spinal muscular atrophy. In addition, we will have a re-analysis performed on the
images obtained from our Phase 3 clinical trial for secretin to improve pancreatic diagnostic imaging and
anticipate that preliminary results will be available by the end of fiscal year 2011, ending on March 31, 2011. We
will continue our Phase 2b clinical trial for uridine to treat bipolar depression and anticipate that preliminary
results will also be available by the end of fiscal year 2011. There may be further increases in expenses if we
acquire additional product candidates.

Selling, general and administrative (“SG&A”) expenses include the associated costs with selling our
commercial products and costs required to support our research and development efforts including legal,
accounting, patent, shareholder services and other administrative functions. In addition, SG&A expenses have
historically included costs associated with various litigation matters.

In fiscal 2010, SG&A costs increased by $1,139,000 or 19% as compared to fiscal 2009. This increase is

primarily due to increased personnel expenses of $1,001,000 primarily due to headcount increases in marketing
and business development including salaries and stock-based compensation.

During fiscal 2009, SG&A costs decreased by $4,240,000 or 42% as compared to fiscal 2008. This decrease

is primarily due to $4,841,000 of litigation costs incurred in fiscal 2008 relating to the Bristol and ImClone
settlements, and a $238,000 decrease in recruiting and relocation costs as certain key board and management
positions were filled in fiscal 2008. These decreases are partially offset by increased personnel expenses of
$899,000 primarily due to headcount increases in marketing and business development including salaries and
stock-based compensation.

We expect SG&A expenses to increase moderately in fiscal 2011 primarily due to slightly higher headcount

and related personnel expenses.

29

Net gain from litigation settlement

On September 10, 2007, Repligen and MIT entered into the ImClone Settlement relating to the lawsuit
against ImClone for infringement of the ‘281 patent. Pursuant to the ImClone Settlement, ImClone made a
payment of $65 million to Repligen and MIT that resulted in net proceeds to Repligen of $40,170,000 after
litigation costs of $13,830,000 and proceeds to MIT of $11,000,000. The ImClone Settlement served as the basis
to dismiss the lawsuit against ImClone and for Repligen to grant ImClone a non-exclusive sublicense to the ‘281
patent and certain other intellectual property.

Investment income

Investment income includes income earned on invested cash balances. Investment income for fiscal 2010,

2009 and 2008 was approximately $870,000, $1,896,000 and $2,051,000, respectively. The decrease of
$1,026,000 or 54% in fiscal 2010 compared to fiscal 2009 and the decrease of $155,000 or 8% in fiscal 2009
compared to fiscal 2008 are primarily attributable to lower interest rates resulting from overall economic
conditions. We expect interest income to vary based on changes in the amount of funds invested and fluctuation
of interest rates.

Benefit from income taxes

In fiscal year 2010, we recorded a tax benefit of approximately $835,000 primarily due to the “Worker,
Homeownership, and Business Assistance Act of 2009” (the “Act”) that was enacted in November 2009. Among
other things, the Act suspended the limitation on the use of net operating losses to offset alternative minimum tax
liabilities, which we expect will enable us to recover $835,000 of alternative minimum taxes paid in prior years.
As a result, the Company had an effective tax rate of negative 17.0%.

Liquidity and capital resources

We have financed our operations primarily through sales of equity securities, revenues derived from product

sales, and research grants, as well as proceeds and royalties from litigation settlements. Our revenue for the
foreseeable future will be limited to our bioprocessing product revenue, royalties from Bristol, and research and
development grants. Given the uncertainties related to pharmaceutical product development, we are currently
unable to reliably estimate when, if ever, our therapeutic product candidates will generate revenue and cash
flows.

At March 31, 2010, we had cash and marketable securities of $59,146,000 compared to $63,961,000 at
March 31, 2009. Deposits for leased office space of $200,000 is classified as restricted cash and is not included
in cash and marketable securities total for either 2010 or 2009.

Cash flows

(In thousands)

Cash provided by (used in)

Year ended March 31,

2010

Increase /
(Decrease)

2009

Increase /
(Decrease)

2008

Operating activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Investing activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Financing activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$(2,448) $ (8,755) $ 6,307
(32,232)
42,153
(1,596)
1,608

9,921
12

$(32,160) $ 38,467
(14,229)
598

(18,003)
(2,194)

Operating activities

In fiscal 2010, our operating activities consumed $2,448,000 of cash which reflects a net loss of
approximately $4,064,000 and non-cash charges totaling approximately $2,386,000 including depreciation,
amortization, and stock-based compensation charges. The remaining cash flow used in operations resulted from
unfavorable changes in various working capital accounts.

30

In fiscal 2009, our operating activities provided cash of $6,307,000 reflecting net income of approximately

$5,746,000 which includes non-cash charges totaling approximately $1,907,000 including depreciation,
amortization, and stock-based compensation charges. The remaining cash flow used in operations resulted from
unfavorable changes in various working capital accounts.

In fiscal 2008, our operating activities provided cash of $38,467,000 reflecting net income of approximately

$37,107,000 which includes non-cash charges totaling approximately $1,659,000 including depreciation,
amortization, and stock-based compensation charges. The remaining cash flow used in operations resulted from
unfavorable changes in various working capital accounts.

Investing activities

In fiscal 2010, our investing activities generated $9,921,000 of cash, which is primarily due to net maturities

of marketable debt securities of $12,299,000 partially offset by $1,780,000 of cash used to acquire the assets of
BioFlash Partners, LLC (see Note 13) and $597,000 for capital expenditures. In fiscal 2009, our investing
activities consumed $32,232,000 of cash, which is primarily due to net purchases of marketable debt securities of
$30,892,000. Also in fiscal 2009, we spent $1,340,000 on capital expenditures as we continued to upgrade both
our research and development and manufacturing capabilities. We place our marketable security investments in
high quality credit instruments as specified in our investment policy guidelines.

Financing activities

In fiscal 2010, exercises of stock options provided cash receipts of $54,000. In fiscal 2009, the repurchase of

common stock consumed $1,954,000 and exercises of stock options provided cash receipts of $402,000.

Off-balance sheet arrangements

We do not have any special purpose entities or off-balance sheet financing arrangements.

Contractual obligations

As of March 31, 2010, we had the following fixed obligations and commitments:

Payments Due By Period

Total

Less than 1
Year

Operating lease obligations . . . . . . . . . . . . . . . . . . . . . .
Purchase obligations . . . . . . . . . . . . . . . . . . . . . . . . . . .
Contractual obligations (1) . . . . . . . . . . . . . . . . . . . . . .

$1,005
1,212
1,776

$ 572
1,212
1,011

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$3,993

$2,795

1 – 3 Years

3 – 5 Years

(In thousands)

$424
—
115

$539

$

9

—
190

$199

More than 5
Years

$—
—
460

$460

(1) These amounts include obligations for minimum contingent consideration from acquisitions as well as for

license, supply and consulting agreements.

Capital requirements

Our future capital requirements will depend on many factors, including the following:

•

•

•

the success of our clinical studies;

the scope of and progress made in our research and development activities;

our ability to acquire additional products or product candidates;

31

•

•

•

•

the extent of any share repurchase activity;

the success of any proposed financing efforts; and

the ability to sustain sales and profits of our bioprocessing products; and

the amount of royalty revenues we receive from Bristol.

Absent acquisitions of additional products, product candidates or intellectual property, we believe our
current cash balances are adequate to meet our cash needs for at least the next twenty-four months. We expect to
incur moderately increased expenses in fiscal 2011 compared to fiscal 2010. This is primarily due to increases in
cost of product revenue associated with higher anticipated product revenue, increased personnel expenses, offset
by moderately lower research and development costs. Our future capital requirements include, but are not limited
to, continued investment in our research and development programs, the acquisition of additional products and
technologies to complement our manufacturing capabilities, capital expenditures primarily associated with
purchases of equipment and continued investment in our intellectual property portfolio.

We plan to continue to invest in key research and development activities. We actively evaluate various

strategic transactions on an ongoing basis, including licensing or acquiring complementary products,
technologies or businesses that would complement our existing portfolio of development programs. We continue
to seek to acquire such potential assets that may offer us the best opportunity to create value for our shareholders.
In order to acquire such assets, we may need to seek additional financing to fund these investments. This may
require the issuance or sale of additional equity or debt securities. The sale of additional equity may result in
additional dilution to our stockholders. Should we need to secure additional financing to acquire a product, fund
future investment in research and development, or meet our future liquidity requirements, we may not be able to
secure such financing, or obtain such financing on favorable terms because of the volatile nature of the
biotechnology marketplace.

Net operating loss carryforwards

At March 31, 2010, we had net operating loss carryforwards of approximately $63,903,000 and business tax

credits carryforwards of approximately $2,118,000 available to reduce future federal income taxes, if any.
Additionally, at March 31, 2010, we had net operating loss carryforwards of approximately $3,061,000 and
business tax credits carryforwards of approximately $5,615,000 available to reduce future state income taxes, if
any. The net operating loss and business tax credits carryforwards will continue to expire at various dates through
March 2030. Net operating loss carryforwards and available tax credits are subject to review and possible
adjustment by the Internal Revenue Service and may be limited in the event of certain changes in the ownership
interest of significant stockholders.

In fiscal year 2010, we recorded a tax benefit of approximately ($835,000) primarily due to the “Worker,
Homeownership, and Business Assistance Act of 2009” (the “Act”) that was enacted in November 2009. Among
other things, the Act suspended the limitation on the use of net operating losses to offset alternative minimum tax
liabilities, and will enable us to receive a refund of $835,000 for alternative minimum taxes paid in prior years. In
fiscal 2009 and 2008, we utilized our net operating loss carryforwards to reduce our income tax provision.

Effects of inflation

Our assets are primarily monetary, consisting of cash, cash equivalents and marketable securities. Because
of their liquidity, these assets are not directly affected by inflation. Since we intend to retain and continue to use
our equipment, furniture and fixtures and leasehold improvements, we believe that the incremental inflation
related to replacement costs of such items will not materially affect our operations. However, the rate of inflation
affects our expenses, such as those for employee compensation and contract services, which could increase our
level of expenses and the rate at which we use our resources.

32

Recent accounting pronouncements

In October 2009, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update

(“ASU”) No. 2009-13, “Multiple-Deliverable Arrangements—a consensus of the FASB Emerging Issues Task
Force” (“ASU 2009-13”). This ASU establishes the accounting and reporting guidance for arrangements under
which a vendor will perform multiple revenue-generating activities. Specifically, the provisions of this update
address how to separate deliverables and how to measure and allocate arrangement consideration to one or more
units of accounting. This update is effective prospectively for revenue arrangements entered into or materially
modified in fiscal years beginning on or after June 15, 2010. Early adoption is permitted. We have not yet
completed our evaluation of ASU 2009-13, but we do not currently believe that adoption will have a material
impact on our results of operations, financial position or cash flows.

In January 2010, the FASB issued ASU No. 2010-06, “Improving Disclosures about Fair Value

Measurements“ (“ASU 2010-06”). This ASU requires new disclosures and clarifies some existing disclosure
requirements about fair value measurements codified within ASC 820, “Fair Value Measurements and
Disclosures,” including significant transfers into and out of Level 1 and Level 2 investments of the fair value
hierarchy. ASU 2010-06 also requires additional information in the roll forward of Level 3 investments including
presentation of purchases, sales, issuances, and settlements on a gross basis. Further clarification for existing
disclosure requirements provides for the disaggregation of assets and liabilities presented, and the enhancement
of disclosures around inputs and valuation techniques. This update is effective for the first interim or annual
reporting period beginning after December 15, 2009, except for the additional information in the roll forward of
Level 3 investments. Those disclosures are effective for fiscal years beginning after December 15, 2010, and for
interim reporting periods within those fiscal years. We adopted ASU 2010-06 in January 2010. The adoption of
this update did not have a material impact on our results of operations, financial position or cash flows.

In April 2010, the FASB issued ASU No. 2010-17, “Milestone Method of Revenue Recognition—a

consensus of the FASB Emerging Issues Task Force” (“ASU 2010-17”). This ASU provides guidance on defining
a milestone and determining when it may be appropriate to apply the milestone method of revenue recognition
for research and development transactions. ASU 2010-17 is effective on a prospective basis for milestones
achieved in fiscal years, and interim periods within those years, beginning on or after June 15, 2010. Early
adoption is permitted. We have not yet completed our evaluation of ASU 2010-17, but we do not currently
believe that adoption will have a material impact on our results of operations, financial position or cash flows.

33

Item 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

Interest rate risk

We have investments in commercial paper, U.S. Government and agency securities as well as corporate
bonds and other debt securities. As a result, we are exposed to potential loss from market risks that may occur as
a result of changes in interest rates, changes in credit quality of the issuer or otherwise.

We generally place our marketable security investments in high quality credit instruments, as specified in

our investment policy guidelines. A hypothetical 100 basis point decrease in interest rates would result in an
approximate $254,000 decrease in the fair value of our investments as of March 31, 2010. We believe, however,
that the conservative nature of our investments mitigates our interest rate exposure, and our investment policy
limits the amount of our credit exposure to any one issue, issuer (with the exception of U.S. agency obligations)
and type of instrument. We do not expect any material loss from our marketable security investments and
therefore believe that our potential interest rate exposure is limited. We intend to hold the majority of our
investments to maturity, in accordance with our business plans.

Item 8.

FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

Financial statements and supplementary data required by Item 8 are set forth at the pages indicated in

Item 15(a) below and are incorporated herein by reference.

Item 9.

CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND
FINANCIAL DISCLOSURE.

None.

Item 9A. CONTROLS AND PROCEDURES

(a) Disclosure Controls and Procedures.

The Company’s management, with the participation of our chief executive officer and principal financial

officer, has evaluated the effectiveness of the Company’s disclosure controls and procedures (as defined in
Rules 13a-15(e) or 15d-15(e) under the Exchange Act) as of the end of the period covered by this report. Based
on such evaluation, our chief executive officer and principal financial officer have concluded that, as of the end
of such period, the Company’s disclosure controls and procedures were effective in ensuring that information
required to be disclosed by the Company in the reports that it files or submits under the Exchange Act is
recorded, processed, summarized and reported, on a timely basis, and is accumulated and communicated to the
Company’s management, including the Company’s chief executive officer and principal financial officer, as
appropriate to allow timely decisions regarding required disclosure.

(b) Management’s Annual Report on Internal Control Over Financial Reporting.

Management of the Company is responsible for establishing and maintaining adequate internal control over
financial reporting. Internal control over financial reporting is defined in Rule 13a-15(f) and 15d-15(f) under the
Exchange Act as a process designed by, or under the supervision of, the Company’s principal executive and
principal financial officers and effected by the Company’s board of directors, management and other personnel to
provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial
statements for external purposes in accordance with U.S. generally accepted accounting principles and includes
those policies and procedures that:

•

pertain to the maintenance of records that in reasonable detail accurately and fairly reflect the
transactions and dispositions of the assets of the Company;

34

•

•

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

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. Projections of any evaluation of effectiveness to future periods are subject to the risks that
controls may become inadequate because of changes in conditions, or that the degree of compliance with the
policies or procedures may deteriorate.

Management assessed the effectiveness of the Company’s internal control over financial reporting as of
March 31, 2010. In making this assessment, management used the criteria established in Internal Control—
Integrated Framework, issued by the Committee of Sponsoring Organizations of the Treadway Commission
(COSO). Based on this assessment, our management concluded that, as of March 31, 2010, our internal control
over financial reporting is effective based on those criteria. Ernst & Young LLP, the independent registered
public accounting firm that audited our financial statements included in this annual report on Form 10-K, has
issued an attestation report on our internal control over financial reporting as of March 31, 2010. Please see
Item 9A of this Form 10-K.

/s/ REPLIGEN CORPORATION

June 10, 2010

35

(c) Attestation Report of the Independent Registered Public Accounting Firm.

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Board of Directors and Stockholders of Repligen Corporation:

We have audited Repligen Corporation’s internal control over financial reporting as of March 31, 2010,
based on criteria established in Internal Control—Integrated Framework issued by the Committee of Sponsoring
Organizations of the Treadway Commission (the COSO criteria). Repligen Corporation’s management is
responsible for maintaining effective internal control over financial reporting, and for its assessment of the
effectiveness of internal control over financial reporting included in the accompanying Management’s Annual
Report on Internal Control Over Financial Reporting. Our responsibility is to express an opinion on the
company’s internal control over financial reporting based on our audit.

We conducted our audit in accordance with the standards of the Public Company Accounting Oversight
Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance
about whether effective internal control over financial reporting was maintained in all material respects. Our
audit included obtaining an understanding of internal control over financial reporting, assessing the risk that a
material weakness exists, testing and evaluating the design and operating effectiveness of internal control based
on the assessed risk, and performing such other procedures as we considered necessary in the circumstances. We
believe that our audit provides a reasonable basis for our opinion.

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 (1) pertain to the maintenance of records that, in reasonable detail,
accurately and fairly reflect the transactions and dispositions of the assets of the company; (2) 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 (3) 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.

In our opinion, Repligen Corporation maintained, in all material respects, effective internal control over

financial reporting as of March 31, 2010, based on the COSO criteria.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board

(United States), the balance sheets of Repligen Corporation as of March 31, 2010 and 2009, and the related
statements of operations, stockholders’ equity, and cash flows for each of the three years in the period ended
March 31, 2010 of Repligen Corporation and our report dated June 10, 2010 expressed an unqualified opinion
thereon.

Boston, Massachusetts
June 10, 2010

/s/ Ernst & Young LLP

36

(d) Changes in Internal Control Over Financial Reporting.

There have not been any changes in the Company’s internal control over financial reporting (as such term is
defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) during the quarter ended March 31, 2010 that
have material affected, or are reasonably likely to materially affect, the Company’s internal control over financial
reporting.

Item 9B. OTHER INFORMATION

None.

37

PART III

Pursuant to General Instructions G to Form 10-K, the information required for Part III, Items 10, 11, 12, 13
and 14, is incorporated herein by reference from the Company’s proxy statement for the 2010 Annual Meeting of
Stockholders.

38

PART IV

Item 15. EXHIBITS AND FINANCIAL STATEMENT SCHEDULES

The following documents are filed as part of this Annual Report on Form 10-K:

(a) (1) Financial Statements:

The financial statements required by this item are submitted in a separate section beginning on page 38 of

this Report, as follows:

Report of Independent Registered Public Accounting Firm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Balance Sheets as of March 31, 2010 and 2009 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Statements of Operations for the Years Ended March 31, 2010, 2009 and 2008 . . . . . . . . . . . . . . . . . . . . . .
Statements of Stockholders’ Equity for the Years Ended March 31, 2010, 2009 and 2008 . . . . . . . . . . . . . .
Statements of Cash Flows for the Years Ended March 31, 2010, 2009 and 2008 . . . . . . . . . . . . . . . . . . . . . .
Notes to Financial Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Page

46
47
48
49
50
51

(a) (2) Financial Statement Schedules:

None.

(a) (3) Exhibits:

The Exhibits which are filed as part of this Annual Report or which are incorporated by reference are set

forth in the Exhibit Index hereto.

EXHIBIT INDEX

Exhibit
Number

3.1

3.2

3.3

4.1

4.2

Document Description

Restated Certificate of Incorporation dated June 30, 1992 and amended September 17, 1999 (filed as
Exhibit 3.1 to Repligen Corporation’s Quarterly Report on Form 10-Q for the quarter ended
September 30, 1999 and incorporated herein by reference) (SEC File No. 000-14656).

Certificate of Designation of Series A Junior Participating Preferred Stock dated March 4, 2003
(filed as Exhibit A of Exhibit 1 to Repligen Corporation’s Registration Statement on Form 8-A filed
March 4, 2003 and incorporated herein by reference) (SEC File No. 000-14656).

Amended and Restated By-laws (filed as Exhibit 3.2 to Repligen Corporation’s Quarterly Report on
Form 10-Q for the quarter ended September 30, 2003 and incorporated herein by reference) (SEC
File No. 000-14656).

Specimen Stock Certificate (filed as Exhibit 4.1 to Repligen Corporation’s Annual Report on
Form 10-K for the year ended March 31, 2002 and incorporated herein by reference) (SEC File
No. 000-14656).

Rights Agreement, dated as of March 3, 2003, between Repligen Corporation and American Stock
Transfer & Trust Company (filed as Exhibit 4.1 to Repligen Corporation’s Current Report on
Form 8-K filed March 4, 2003 and incorporated herein by reference) (SEC File No. 000-14656).

10.1*

Consulting Agreement, dated November 1, 1981, between Dr. Alexander Rich and Repligen
Corporation. (filed as Exhibit 10.2 to Repligen Corporation’s Annual Report on Form 10-K for the
year ended March 31, 2002 and incorporated herein by reference) (SEC File No. 000-14656).

39

Exhibit
Number

10.2*

10.3*

10.4*

10.5*

10.6*

10.7*

10.8*

10.8.1*

10.8.2*

10.9

10.10#

10.11#

10.12

10.13#

Document Description

Employment Agreement, dated March 14, 1996, between Repligen Corporation and Walter C.
Herlihy (filed as Exhibit 10.3 to Repligen Corporation’s Annual Report on Form 10-K for the year
ended March 31, 2002 and incorporated herein by reference) (SEC File No. 000-14656).

Employment Agreement, dated March 14, 1996, between Repligen Corporation and James R.
Rusche (filed as Exhibit 10.4 to Repligen Corporation’s Annual Report on Form 10-K for the year
ended March 31, 2002 and incorporated herein by reference) (SEC File No. 000-14656).

Employment Agreement, dated March 14, 1996, between Repligen Corporation and Daniel P. Witt
(filed as Exhibit 10.5 to Repligen Corporation’s Annual Report on Form 10-K for the year ended
March 31, 2002 and incorporated herein by reference) (SEC File No. 000-14656).

Employment Offer Letter dated February 29, 2008 by and between Repligen Corporation and
William Kelly (filed as Exhibit 10.20 to Repligen Corporation’s Annual Report on Form 10-K for
the year ended March 31, 2008 and incorporated herein by reference).

Repligen Executive Incentive Compensation Plan (filed as Exhibit 10.1 to Repligen Corporation’s
Current Report on form 8-K filed on December 14, 2005 and incorporated herein by reference).

The Amended 1992 Repligen Corporation Stock Option Plan, as amended (filed as Exhibit 4.2 to
Repligen Corporation’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2000
and incorporated herein by reference) (SEC File No. 000-14656).

The Second Amended and Restated 2001 Repligen Corporation Stock Plan (filed as Exhibit 10.1 to
Repligen Corporation’s Current Report on Form 8-K filed on September 18, 2008 and incorporated
herein by reference).

The Second Amended and Restated 2001 Repligen Corporation Stock Option Plan, Form of
Incentive Stock Option Plan (filed as Exhibit 10.14 to Repligen Corporation’s Annual Report on
Form 10-K for the year ended March 31, 2005 and incorporated herein by reference).

The Amended and Restated 2001 Repligen Corporation Stock Plan, Form of Restricted Stock
Agreement (filed as Exhibit 10.1 to Repligen Corporation’s Current Report on Form 8-K filed on
January 9, 2006 and incorporated herein by reference).

Common Stock Purchase Warrant dated April 6, 2007 (filed as Exhibit 4.1 to Repligen
Corporation’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2007 and incorporated
herein by reference).

Manufacturing Transfer Agreement dated as of December 17, 1998 among the Company and
Amersham Pharmacia Biotech AB (filed as Exhibit 10.1 to Repligen Corporation’s Quarterly
Report on Form 10-Q for the quarter ended December 31, 1998 and incorporated herein by
reference) (SEC File No. 000-14656).

License Agreement dated as of July 24, 2000 with University of Michigan (filed as Exhibit 10.1 to
Repligen Corporation’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2000
and incorporated herein by reference) (SEC File No. 000-14656).

Lease Between Repligen Corporation as Tenant and West Seyon LLC as Landlord, 35 Seyon Street,
Waltham, MA (filed as Exhibit 10.1 to Repligen Corporation’s Quarterly Report on Form 10-Q for
the quarter ended December 31, 2001 and incorporated herein by reference) (SEC File No. 000-
14656).

Settlement Agreement by and between ChiRhoClin, Inc. and Repligen Corporation, and dated as of
May 9, 2005 (filed as Exhibit 10.1 to Repligen Corporation’s Quarterly Report on Form 10-Q for
the quarter ended June 30, 2005 and incorporated herein by reference).

40

Exhibit
Number

10.14#

10.15#

10.16#

Document Description

License Agreement by and between The Scripps Research Institute and Repligen Corporation
dated April 6, 2007 (filed as Exhibit 10.18 to Repligen Corporation’s Annual Report on
Form 10-K for the year ended March 31, 2007 and incorporated herein by reference).

Settlement Agreement and Releases dated September 10, 2007 by and among Repligen
Corporation, Massachusetts Institute of Technology and ImClone Systems Incorporated (filed as
Exhibit 10.1 to Repligen Corporation’s Quarterly Report on Form 10-Q for the quarter ended
September 30, 2007 and incorporated herein by reference).

Settlement and Release Agreement dated April 7, 2008 by and among Repligen Corporation, The
Regents of the University of Michigan and Bristol-Myers Squibb Company (filed as Exhibit 10.1
to Repligen Corporation’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2008 and
incorporated herein by reference).

10.17#+

Strategic Supplier Alliance Agreement dated January 28, 2010 by and between Repligen
Corporation and GE Healthcare Bio-Sciences AB.

23.1+

24.1+

31.1+

31.2+

32.1+

Consent of Ernst & Young LLP.

Power of Attorney (included on signature page).

Rule 13a-14(a)/15d-14(a) Certification.

Rule 13a-14(a)/15d-14(a) Certification.

Certification Pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the
Sarbanes-Oxley Act of 2002.

# Confidential treatment obtained as to certain portions.
* Management contract or compensatory plan or arrangement.
+ Filed herewith.

The exhibits listed above are not contained in the copy of the Annual Report on Form 10-K distributed to
stockholders. Upon the request of any stockholder entitled to vote at the 2010 annual meeting, the Registrant will
furnish that person without charge a copy of any exhibits listed above. Requests should be addressed to Repligen
Corporation, 41 Seyon Street, Waltham, MA 02453.

41

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this

report to be signed on its behalf by the undersigned thereunto duly authorized.

Date: June 10, 2010

By:

/S/ WALTER C. HERLIHY

Walter C. Herlihy
President and Chief Executive Officer

REPLIGEN CORPORATION

POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that each person whose signature appears below hereby
makes, constitutes and appoints Walter C. Herlihy and William J. Kelly with full power to act without the other,
his true and lawful attorney-in-fact and agent, with full power of substitution and resubstitution, for him and in
his name, place and stead, in any and all capacities to sign any or all amendments to this Form 10-K, and to file
the same with all exhibits thereto, and other documents in connection therewith, with the Securities and
Exchange Commission, granting unto said attorney-in-fact and agents, and each of them, full power and authority
to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as
fully to all intents and purposes as he might or could do in person, hereby ratifying and confirming all that said
attorney-in-fact and agents of any of them, or any substitute or substitutes, lawfully do or cause to be done by
virtue hereof.

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 registrant and in the capacities and on the dates indicated.

Signature

Title

Date

/s/ WALTER HERLIHY
Walter C. Herlihy, Ph.d.

/s/ WILLIAM J. KELLY

William J. Kelly

/s/ ALEXANDER RICH
Alexander Rich, M.D.

/s/ KAREN DAWES

Karen Dawes

/s/ ALFRED L. GOLDBERG
Alfred L. Goldberg, Ph.D.

/s/ EARL W. HENRY
Earl W. Henry, M.D.

President, Chief Executive Officer
and Director
(Principal executive officer)

Chief Financial Officer
(Principal financial and accounting
officer)

June 10, 2010

June 10, 2010

Chairman of the Board

June 10, 2010

Director

Director

Director

June 10, 2010

June 10, 2010

June 10, 2010

/s/ THOMAS F. RYAN, JR.

Director

June 10, 2010

Thomas F. Ryan, Jr.

/s/ GLENN L. COOPER
Glenn L. Cooper, M.D.

Director

42

June 10, 2010

Exhibit
Number

3.1

3.2

3.3

4.1

4.2

10.1*

10.2*

10.3*

10.4*

10.5*

10.6*

10.7*

10.8*

EXHIBIT INDEX

Document Description

Restated Certificate of Incorporation dated June 30, 1992 and amended September 17, 1999 (filed
as Exhibit 3.1 to Repligen Corporation’s Quarterly Report on Form 10-Q for the quarter ended
September 30, 1999 and incorporated herein by reference) (SEC File No. 000-14656).

Certificate of Designation of Series A Junior Participating Preferred Stock dated March 4, 2003
(filed as Exhibit A of Exhibit 1 to Repligen Corporation’s Registration Statement on Form 8-A
filed March 4, 2003 and incorporated herein by reference) (SEC File No. 000-14656).

Amended and Restated By-laws (filed as Exhibit 3.2 to Repligen Corporation’s Quarterly Report
on Form 10-Q for the quarter ended September 30, 2003 and incorporated herein by reference)
(SEC File No. 000-14656).

Specimen Stock Certificate (filed as Exhibit 4.1 to Repligen Corporation’s Annual Report on
Form 10-K for the year ended March 31, 2002 and incorporated herein by reference) (SEC File No.
000-14656).

Rights Agreement, dated as of March 3, 2003, between Repligen Corporation and American Stock
Transfer & Trust Company (filed as Exhibit 4.1 to Repligen Corporation’s Current Report on
Form 8-K filed March 4, 2003 and incorporated herein by reference) (SEC File No. 000-14656).

Consulting Agreement, dated November 1, 1981, between Dr. Alexander Rich and Repligen
Corporation. (filed as Exhibit 10.2 to Repligen Corporation’s Annual Report on Form 10-K for the
year ended March 31, 2002 and incorporated herein by reference) (SEC File No. 000-14656).

Employment Agreement, dated March 14, 1996, between Repligen Corporation and Walter C.
Herlihy (filed as Exhibit 10.3 to Repligen Corporation’s Annual Report on Form 10-K for the year
ended March 31, 2002 and incorporated herein by reference) (SEC File No. 000-14656).

Employment Agreement, dated March 14, 1996, between Repligen Corporation and James R.
Rusche (filed as Exhibit 10.4 to Repligen Corporation’s Annual Report on Form 10-K for the year
ended March 31, 2002 and incorporated herein by reference) (SEC File No. 000-14656).

Employment Agreement, dated March 14, 1996, between Repligen Corporation and Daniel P. Witt
(filed as Exhibit 10.5 to Repligen Corporation’s Annual Report on Form 10-K for the year ended
March 31, 2002 and incorporated herein by reference) (SEC File No. 000-14656).

Employment Offer Letter dated February 29, 2008 by and between Repligen Corporation and
William Kelly (filed as Exhibit 10.20 to Repligen Corporation’s Annual Report on Form 10-K for
the year ended March 31, 2008 and incorporated herein by reference).

Repligen Executive Incentive Compensation Plan (filed as Exhibit 10.1 to Repligen Corporation’s
Current Report on form 8-K filed on December 14, 2005 and incorporated herein by reference).

The Amended 1992 Repligen Corporation Stock Option Plan, as amended (filed as Exhibit 4.2 to
Repligen Corporation’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2000
and incorporated herein by reference) (SEC File No. 000-14656).

The Second Amended and Restated 2001 Repligen Corporation Stock Plan (filed as Exhibit 10.1 to
Repligen Corporation’s Current Report on Form 8-K filed on September 18, 2008 and incorporated
herein by reference).

10.8.1*

10.8.2*

The Second Amended and Restated 2001 Repligen Corporation Stock Option Plan, Form of
Incentive Stock Option Plan (filed as Exhibit 10.14 to Repligen Corporation’s Annual Report on
Form 10-K for the year ended March 31, 2005 and incorporated herein by reference).

The Amended and Restated 2001 Repligen Corporation Stock Plan, Form of Restricted Stock
Agreement (filed as Exhibit 10.1 to Repligen Corporation’s Current Report on Form 8-K filed on
January 9, 2006 and incorporated herein by reference).

43

Exhibit
Number

10.9

10.10#

10.11#

10.12

10.13#

10.14#

10.15#

10.16#

Document Description

Common Stock Purchase Warrant dated April 6, 2007 (filed as Exhibit 4.1 to Repligen
Corporation’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2007 and
incorporated herein by reference).

Manufacturing Transfer Agreement dated as of December 17, 1998 among the Company and
Amersham Pharmacia Biotech AB (filed as Exhibit 10.1 to Repligen Corporation’s Quarterly
Report on Form 10-Q for the quarter ended December 31, 1998 and incorporated herein by
reference) (SEC File No. 000-14656).

License Agreement dated as of July 24, 2000 with University of Michigan (filed as Exhibit 10.1 to
Repligen Corporation’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2000
and incorporated herein by reference) (SEC File No. 000-14656).

Lease Between Repligen Corporation as Tenant and West Seyon LLC as Landlord, 35 Seyon
Street, Waltham, MA (filed as Exhibit 10.1 to Repligen Corporation’s Quarterly Report on
Form 10-Q for the quarter ended December 31, 2001 and incorporated herein by reference) (SEC
File No. 000-14656).

Settlement Agreement by and between ChiRhoClin, Inc. and Repligen Corporation, and dated as
of May 9, 2005 (filed as Exhibit 10.1 to Repligen Corporation’s Quarterly Report on Form 10-Q
for the quarter ended June 30, 2005 and incorporated herein by reference).

License Agreement by and between The Scripps Research Institute and Repligen Corporation
dated April 6, 2007 (filed as Exhibit 10.18 to Repligen Corporation’s Annual Report on Form 10-
K for the year ended March 31, 2007 and incorporated herein by reference).

Settlement Agreement and Releases dated September 10, 2007 by and among Repligen
Corporation, Massachusetts Institute of Technology and ImClone Systems Incorporated (filed as
Exhibit 10.1 to Repligen Corporation’s Quarterly Report on Form 10-Q for the quarter ended
September 30, 2007 and incorporated herein by reference).

Settlement and Release Agreement dated April 7, 2008 by and among Repligen Corporation, The
Regents of the University of Michigan and Bristol-Myers Squibb Company (filed as Exhibit 10.1
to Repligen Corporation’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2008 and
incorporated herein by reference).

10.17#+

Strategic Supplier Alliance Agreement dated January 28, 2010 by and between Repligen
Corporation and GE Healthcare Bio-Sciences AB.

23.1+

24.1+

31.1+

31.2+

32.1+

Consent of Ernst & Young LLP.

Power of Attorney (included on signature page).

Rule 13a-14(a)/15d-14(a) Certification.

Rule 13a-14(a)/15d-14(a) Certification.

Certification Pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the
Sarbanes-Oxley Act of 2002.

# Confidential treatment obtained as to certain portions.
* Management contract or compensatory plan or arrangement.
+ Filed herewith.

44

INDEX TO FINANCIAL STATEMENTS

Report of Independent Registered Public Accounting Firm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Balance Sheets as of March 31, 2010 and 2009 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Statements of Operations for the Years Ended March 31, 2010, 2009 and 2008 . . . . . . . . . . . . . . . . . . . . . .
Statements of Stockholders’ Equity for the Years Ended March 31, 2010, 2009 and 2008 . . . . . . . . . . . . . .
Statements of Cash Flows for the Years Ended March 31, 2010, 2009 and 2008 . . . . . . . . . . . . . . . . . . . . . .
Notes to Financial Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Page

46
47
48
49
50
51

45

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Board of Directors and Stockholders of Repligen Corporation:

We have audited the accompanying balance sheets of Repligen Corporation as of March 31, 2010 and 2009,

and the related statements of operations, stockholders’ equity, and cash flows for each of the three years in the
period ended March 31, 2010. These financial statements are the responsibility of the Company’s management.
Our responsibility is to express an opinion on these financial statements based on our audits.

We conducted our audits in accordance with the standards of the Public Company Accounting Oversight
Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance
about whether the financial statements are free of material misstatement. An audit includes examining, on a test
basis, evidence supporting the amounts and disclosures in the financial statements. An audit also includes
assessing the accounting principles used and significant estimates made by management, as well as evaluating
the overall financial statement presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in all material respects, the financial
position of Repligen Corporation at March 31, 2010 and 2009, and the results of its operations, and its cash flows
for each of the three years in the period ended March 31, 2010, in conformity with U.S. generally accepted
accounting principles.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board

(United States), Repligen Corporation’s internal control over financial reporting as of March 31, 2010, based on
criteria established in Internal Control-Integrated Framework issued by the Committee of Sponsoring
Organizations of the Treadway Commission and our report dated June 10, 2010 expressed an unqualified opinion
thereon.

/s/ Ernst & Young LLP

Boston, Massachusetts
June 10, 2010

46

REPLIGEN CORPORATION
BALANCE SHEETS

March 31, 2010

March 31, 2009

Assets
Current assets:

Cash and cash equivalents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Marketable securities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Accounts receivable, less reserve for doubtful accounts of $10,000 . . . . . .
Royalties receivable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inventories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Prepaid expenses and other current assets . . . . . . . . . . . . . . . . . . . . . . . . . .

$ 12,526,040
40,608,710
570,038
2,296,000
2,201,140
1,479,107

$

5,041,410
43,817,915
540,779
2,036,800
2,413,227
933,585

Total current assets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

59,681,035

54,783,716

Property, plant and equipment, at cost:

Leasehold improvements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Furniture and fixtures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3,855,616
4,176,281
567,480

3,845,247
3,527,469
513,501

Total property, plant and equipment, at cost
. . . . . . . . . . . . . . . . . . . .
Less: Accumulated depreciation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8,599,377
(5,466,354)

7,886,217
(4,216,430)

Property, plant and equipment, net . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Long-term marketable securities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Intangible assets, net . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Goodwill . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Restricted cash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3,133,023
6,011,697
1,400,208
994,000
200,000

3,669,787
15,101,239
—
—
200,000

Total assets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$ 71,419,963

$ 73,754,742

Liabilities and stockholders’ equity
Current liabilities:

Accounts payable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Accrued liabilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$

Total current liabilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Long-term liabilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Total liabilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Commitments and contingencies (Notes 5, 10, 11 and 12)
Stockholders’ equity:
Preferred stock, $.01 par value, 5,000,000 shares authorized, no shares issued

$

991,005
3,666,135

4,657,140
642,447

5,299,587

1,922,572
2,626,341

4,548,913
82,398

4,631,311

or outstanding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

—

—

Common stock, $.01 par value, 40,000,000 shares authorized; issued and

outstanding 30,761,807 shares at March 31, 2010 and 30,741,707 shares at
March 31, 2009 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Additional paid-in capital . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Accumulated deficit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

307,618
183,733,863
(117,921,105)

307,417
182,673,275
(113,857,261)

Total stockholders’ equity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

66,120,376

69,123,431

Total liabilities and stockholders’ equity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$ 71,419,963

$ 73,754,742

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

47

REPLIGEN CORPORATION
STATEMENTS OF OPERATIONS

Years ended March 31,

2010

2009

2008

Revenue:

Product revenue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Royalty and other revenue . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$10,304,727
10,666,342

$14,528,916
14,832,605

$ 18,587,376
708,905

Total revenue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

20,971,069

29,361,521

19,296,281

Operating expenses: (1)

Cost of product revenue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cost of royalty and other revenue . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Research and development
Selling, general and administrative . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . .
Net gain from litigation settlement

Total operating expenses . . . . . . . . . . . . . . . . . . . . . . . . . .
(Loss) income from operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Investment income . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Interest expense . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

(Loss) income before taxes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Income tax (benefit) provision . . . . . . . . . . . . . . . . . . . . . . . . . .

4,159,002
1,347,168
14,159,721
7,071,859
—

26,737,750
(5,766,681)
870,043
(1,972)

(4,898,610)
(834,766)

5,685,577
1,091,297
12,771,573
5,933,090

—

25,481,537
3,879,984
1,895,706
(2,963)

6,147,745
12,500
7,240,812
10,173,400
(40,170,000)

(16,595,543)
35,891,824
2,051,258
(9,097)

5,772,727
26,699

37,933,985
827,471

Net (loss) income . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$ (4,063,844) $ 5,746,028

$ 37,106,514

Earnings per share:

Basic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Diluted . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$

$

(0.13) $

(0.13) $

0.19

0.18

$

$

1.20

1.18

Weighted average shares outstanding:

Basic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

30,752,041

30,957,957

30,834,491

Diluted . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

30,752,041

31,290,233

31,320,997

(1)

Includes non-cash stock-based compensation as follows:

Cost of product revenue . . . . . . . . . . . . . . . . . . . . . . . . . . .
Research and development
. . . . . . . . . . . . . . . . . . . . . . . .
Selling, general and administrative . . . . . . . . . . . . . . . . . .

$

40,941
209,335
756,522

$

47,686
172,872
602,687

$

28,134
106,870
389,383

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

48

REPLIGEN CORPORATION
STATEMENTS OF STOCKHOLDERS’ EQUITY

Common Stock

Number of Shares

Amount

Additional
Paid-in Capital

Accumulated
Deficit

Stockholders’
Equity

Balance, March 31, 2007 . . . . . . . .

30,477,635

$304,776

$182,916,856

$(157,683,334) $25,538,298

Share-based compensation

expense . . . . . . . . . . . . . . . . . . . .

Issuance of common stock for

license . . . . . . . . . . . . . . . . . . . . .
Exercise of stock options . . . . . . . .
Net income . . . . . . . . . . . . . . . . . . .

87,464
507,835

875
5,078

524,387

299,125
632,577

524,387

300,000
637,655
37,106,514

37,106,514

Balance, March 31, 2008 . . . . . . . .

31,072,934

$310,729

$184,372,945

$(120,576,820) $64,106,854

Share-based compensation

expense . . . . . . . . . . . . . . . . . . . .

Repurchase and retirement of

treasury stock . . . . . . . . . . . . . . .
Exercise of stock options . . . . . . . .
Net income . . . . . . . . . . . . . . . . . . .

823,245

823,245

(492,827)
161,600

(4,928)
1,616

(2,923,058)
400,143

973,530

5,746,028

(1,954,456)
401,759
5,746,028

Balance, March 31, 2009 . . . . . . . .

30,741,707

$307,417

$182,673,275

$(113,857,261) $69,123,431

Share-based compensation

expense . . . . . . . . . . . . . . . . . . . .
Exercise of stock options . . . . . . . .
Net loss . . . . . . . . . . . . . . . . . . . . . .

20,100

201

1,006,798
53,790

1,006,798
53,991
(4,063,844)

(4,063,844)

Balance, March 31, 2010 . . . . . . . .

30,761,807

$307,618

$183,733,863

$(117,921,105) $66,120,376

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

49

REPLIGEN CORPORATION
STATEMENTS OF CASH FLOWS

Cash flows from operating activities:
Net (loss) income: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Adjustments to reconcile net (loss) income to net cash

(used in) provided by operating activities:

Years ended March 31,

2010

2009

2008

$ (4,063,844) $ 5,746,028

$ 37,106,514

Issuance of common stock for license . . . . . . . . . . . . . .
Depreciation and amortization . . . . . . . . . . . . . . . . . . . .
Stock-based compensation expense . . . . . . . . . . . . . . . .
Loss on disposal of assets . . . . . . . . . . . . . . . . . . . . . . . .

—
1,378,999
1,006,798
905

Changes in assets and liabilities:

Accounts receivable . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Royalties receivable . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inventories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Prepaid expenses and other current assets . . . . . . . . . . .
Accounts payable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Accrued liabilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Long-term liabilities . . . . . . . . . . . . . . . . . . . . . . . . . . . .

(29,259)
(259,200)
212,087
(545,522)
(931,567)
782,200
49

—
1,077,347
823,245
6,123

520,822
(1,972,600)
391,020
(226,238)
(799,337)
801,379
(60,645)

300,000
824,626
524,387
9,559

260,528
(242,635)
(1,289,676)
(261,932)
1,560,405
(267,876)
(57,299)

Net cash (used in) provided by operating activities . . . . . . . . . . . .

(2,448,354)

6,307,144

38,466,601

Cash flows from investing activities:

Purchases of marketable securities . . . . . . . . . . . . . . . . .
Redemptions of marketable securities . . . . . . . . . . . . . .
Acquisition of assets of BioFlash Partners, LLC . . . . . .
Purchases of property, plant and equipment . . . . . . . . . .

(47,038,060)
59,336,807
(1,780,000)
(597,349)

(56,865,473)
25,973,235
—

(1,339,999)

(54,797,953)
41,671,877

—

(1,102,585)

Net cash provided by (used in) investing activities . . . . . . . . . . . .

9,921,398

(32,232,237)

(14,228,661)

Cash flows from financing activities:

Exercise of stock options . . . . . . . . . . . . . . . . . . . . . . . .
Repurchase of common stock . . . . . . . . . . . . . . . . . . . . .
Principal payments under capital lease obligations . . . .

53,991
—
(42,405)

401,759
(1,954,456)
(42,938)

Net cash provided by (used in) financing activities . . . . . . . . . . . .

11,586

(1,595,635)

637,655
—
(39,962)

597,693

Net increase (decrease) in cash and cash equivalents . . . . . . . . . . .
Cash and cash equivalents, beginning of period . . . . . . . . . . . . . . .

7,484,630
5,041,410

(27,520,728)
32,562,138

24,835,633
7,726,505

Cash and cash equivalents, end of period . . . . . . . . . . . . . . . . . . . .

$ 12,526,040

$ 5,041,410

$ 32,562,138

Supplemental disclosure of non-cash investing activities:
Consideration transferred in acquisition of BioFlash

Partners, LLC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Supplemental disclosure of cash flow information:

Income taxes (refunded) paid . . . . . . . . . . . . . . . . . . . . . . . . .

$

$

Non-cash tender of common stock to exercise stock

560,000

$

— $

—

(135,157) $

166,000

$

800,000

options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$

— $

— $

564,003

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

50

REPLIGEN CORPORATION
NOTES TO FINANCIAL STATEMENTS

1. Organization and Nature of Business

Repligen Corporation (“Repligen” or the “Company”) is a biopharmaceutical company focused on the
development and commercialization of innovative therapies that harness biological pathways and deliver value to
patients and clinicians in neurology, gastroenterology and orphan diseases. The Company is currently conducting
a number of drug development programs for diseases such as pancreatitis, bipolar disorder, Friedreich’s ataxia
and spinal muscular atrophy. Repligen also has a bioprocessing business that focuses on the development and
commercialization of products that are used for the production of biopharmaceuticals. In addition, the Company
receives royalties from Bristol-Myers Squibb Company (“Bristol”) on their net sales in the United States of their
product Orencia®.

The Company’s business strategy is to invest the profits from current bioprocessing products sales and

royalty and other revenues, as well as use existing financial resources to advance the development of its
therapeutic product candidates and our bioprocessing business.

The Company is subject to a number of risks typically associated with companies in the biotechnology
industry. Principally those risks include the Company’s dependence on collaborative arrangements, development
by the Company or its competitors of new technological innovations, dependence on key personnel, protection of
proprietary technology, compliance with the U.S. Food and Drug Administration and other governmental
regulations and approval requirements, as well as the ability to grow the Company’s business and obtain
adequate funding to finance this growth.

2.

Summary of Significant Accounting Policies

Use of Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the

United States requires management to make estimates and assumptions that affect the reported amounts of assets
and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the
reported amounts of revenues and expenses during the reporting period. Actual results could differ from those
estimates.

Revenue Recognition

The Company generates product revenues from the sale of bioprocessing products to customers in the

pharmaceutical and process chromatography industries. The Company recognizes revenue related to product
sales upon delivery of the product to the customer as long as there is persuasive evidence of an arrangement, the
sales price is fixed or determinable and collection of the related receivable is reasonably assured. Determination
of whether these criteria have been met is based on management’s judgments primarily regarding the fixed nature
of the fee charged for product delivered, and the collectability of those fees. The Company has a few
longstanding customers who comprise the majority of revenue and have excellent payment history and therefore
the Company does not require collateral. The Company has had no significant write-offs of uncollectible invoices
in the periods presented.

At the time of sale, the Company also evaluates the need to accrue for warranty and sales returns. The
supply agreements the Company has with its customers and related purchase orders identify the terms and
conditions of each sale and the price of the goods ordered. Due to the nature of the sales arrangements, inventory
produced for sale is tested for quality specifications prior to shipment. Since the product is manufactured to order
and in compliance with required specifications prior to shipment, the likelihood of sales return, warranty or other

51

issues is largely diminished. Sales returns and warranty issues are infrequent and have had nominal impact on the
Company’s financial statements historically.

In April 2008, the Company settled its outstanding litigation with Bristol and began recognizing royalty
revenue in fiscal year 2009 for Bristol’s net sales in the United States of Orencia® which is used in the treatment
of rheumatoid arthritis. Pursuant to the Bristol Settlement (as defined in Note 10), the Company recognized
royalty revenue of approximately $8,980,000 and $13,383,000 in fiscal years 2010 and 2009, respectively. The
$13,383,000 recognized in fiscal 2009 included an initial $5.0 million royalty payment, $1.3 million in royalties
for sales of Orencia® from January 1, 2008 to March 31, 2008, as well as $7.1 million for sales in fiscal year
2009. Revenue earned from Bristol royalties is recorded in the periods when it is earned based on royalty reports
sent by Bristol to the Company. The Company has no continuing obligations to Bristol as a result of this
settlement.

Additionally, the Company earned and recognized approximately $1,009,000, $776,000 and $244,000 in
fiscal years 2010, 2009 and 2008, respectively, in royalty revenue from ChiRhoClin for their sales of secretin.
Revenue earned from ChiRhoClin royalties is recorded in the periods when it is earned based on royalty reports
sent by ChiRhoClin to the Company. In December 2009, ChiRhoClin fulfilled its royalty obligations to the
Company for its sales of secretin. The Company does not expect to recognize any further royalty revenue from
ChiRhoClin.

In fiscal years 2010 and 2009, the Company recognized approximately $552,000 and $564,000,
respectively, of revenue from a sponsored research and development project under an agreement with the
Muscular Dystrophy Association. In addition, the Company recognized approximately $125,000 and $110,000 in
fiscal years 2010 and 2009, respectively, under other sponsored research and development projects. During fiscal
2008, the Company recognized approximately $365,000 under an agreement with the Stanley Medical Research
Institute and $100,000 under another sponsored research and development project.

Research revenue is recognized when the expense has been incurred and services have been performed.
Determination of which costs incurred qualify for reimbursement under the terms of the Company’s contractual
agreements and the timing of when such costs were incurred involves the judgment of management. The
Company’s calculations are based upon the agreed-upon terms as stated in the arrangements. However, should
the estimated calculations change or be challenged by other parties to the agreements, research revenue may be
adjusted in subsequent periods. The calculations have not historically changed or been challenged and the
Company does not anticipate any subsequent change in its revenue related to sponsored research and
development projects.

There have been no material changes to the Company’s initial estimates related to revenue recognition in

any periods presented in the accompanying financial statements.

Risks and Uncertainties

The Company evaluates its operations periodically to determine if any risks and uncertainties exist that

could impact its operations in the near term. The Company does not believe that there are any significant risks
which have not already been disclosed in the financial statements. A loss of certain suppliers could temporarily
disrupt operations, although alternate sources of supply exist for these items. The Company has mitigated these
risks by working closely with key suppliers, identifying alternate sources and developing contingency plans.

Comprehensive Income (Loss)

Comprehensive income is defined as the change in equity of a business enterprise during a period resulting
from transactions and other events and circumstances from non-owner sources. The Company’s comprehensive
income/loss is equal to the reported net income/loss for all periods presented.

52

Cash, Cash Equivalents and Marketable Securities

At March 31, 2010, the Company’s investments included money market funds as well as short-term and
long-term marketable securities, which are classified as held-to-maturity investments as the Company has the
positive intent and ability to hold the investments to maturity. These investments are therefore recorded on an
amortized cost basis. Marketable securities are investments with original maturities of greater than 90 days.
Long-term marketable securities are securities with maturities of greater than one year.

Cash, cash equivalents and marketable securities consist of the following:

As of March 31,

2010

2009

Cash and cash equivalents . . . . . . . . . . . . . . . . . . . .

$12,526,040

$ 5,041,410

Marketable securities:

U.S. Government and agency securities . . . . .
Corporate and other debt securities . . . . . . . . .

23,009,237
17,599,473

20,871,059
22,946,856

$40,608,710

$43,817,915

Long-term marketable securities:

U.S. Government and agency securities . . . . .
Corporate and other debt securities . . . . . . . . .

3,261,524
2,750,173

5,032,385
10,068,854

Total

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$59,146,447

$63,960,564

$ 6,011,697

$15,101,239

The average remaining maturity of marketable securities at March 31, 2010 is approximately 6.5 months.

Management reviewed the Company’s investments as of March 31, 2010 and concluded that there are no
securities with other than temporary impairments in the investment portfolio. The Company does not intend to
sell any investments and it is not more likely than not that the Company will be required to sell the investments
before recovery of their amortized cost bases at maturity. There were no realized gains or losses on the
investments for the years ended March 31, 2010, 2009 and 2008.

Investments in held-to-maturity debt securities consisted of the following at March 31, 2010:

March 31, 2010

Gross
Unrealized
Gain

Gross
Unrealized
Loss

Amortized
Cost

Fair Value

Marketable securities:

U.S. Government and agency securities . . . . . . . . . . .
Corporate and other debt securities . . . . . . . . . . . . . . .

$23,009,237
17,599,473

$ 25,883
82,760

$ (1,748) $23,033,372
17,682,233

—

Long-term marketable securities:

U.S. Government and agency securities . . . . . . . . . . .
Corporate and other debt securities . . . . . . . . . . . . . . .

40,608,710

108,643

(1,748)

40,715,605

3,261,524
2,750,173

6,011,697

10,849
28,105

38,954

(8,546)
—

(8,546)

3,263,827
2,778,278

6,042,105

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$46,620,407

$147,597

$(10,294) $46,757,710

All investments in held-to-maturity debt securities with gross unrealized losses have been in unrealized loss

positions for less than 12 months.

53

Investments in held-to-maturity debt securities consisted of the following at March 31, 2009:

March 31, 2009

Gross
Unrealized
Gain

Gross
Unrealized
Loss

Amortized
Cost

Fair Value

Marketable securities:

U.S. Government and agency securities . . . . . . . . . . .
Corporate and other debt securities . . . . . . . . . . . . . . .

$20,871,059
22,946,856

$113,154
77,916

$

(1,051) $20,983,162
22,942,684
(82,088)

Long-term marketable securities:

U.S. Government and agency securities . . . . . . . . . . .
Corporate and other debt securities . . . . . . . . . . . . . . .

43,817,915

191,070

(83,139)

43,925,846

5,032,385
10,068,854

15,101,239

21,835
56,742

78,577

—
(20,714)

5,054,220
10,104,882

(20,714)

15,159,102

Total

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$58,919,154

$269,647

$(103,853) $59,084,948

The contractual maturities of held-to-maturity debt securities at March 31, 2010 were as follows:

Due in 1 year or less . . . . . . . . . . . . . . . . . . . . . . . .
Due in 1 to 2 years . . . . . . . . . . . . . . . . . . . . . . . . . .

$40,608,710
6,011,697

$40,715,605
6,042,105

$46,620,407

$46,757,710

Amortized
Cost

Fair Value

Fair Value Measurement

In determining the fair value of its assets and liabilities, the Company uses various valuation approaches.

The Company employs a hierarchy for inputs used in measuring fair value that maximizes the use of observable
inputs and minimizes the use of unobservable inputs by requiring that observable inputs be used when available.
Observable inputs are inputs that market participants would use in pricing the asset or liability based on market
data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the
Company’s assumptions about the inputs that market participants would use in pricing the asset or liability and
are developed based on the best information available in the circumstances. The fair value hierarchy is broken
down into three levels based on the source of inputs as follows:

Level 1 — Valuations based on unadjusted quoted prices in active markets for identical assets or liabilities that

the Company has the ability to access

Level 2 — Valuations based on quoted prices for similar assets or liabilities in active markets, quoted prices for

identical or similar assets or liabilities in markets that are not active and models for which all
significant inputs are observable, either directly or indirectly

Level 3 — Valuations based on inputs that are unobservable and significant to the overall fair value

measurement

The availability of observable inputs can vary among the various types of financial assets and liabilities. To
the extent that the valuation is based on models or inputs that are less observable or unobservable in the market,
the determination of fair value requires more judgment. In certain cases, the inputs used to measure fair value
may fall into different levels of the fair value hierarchy. In such cases, for financial statement disclosure
purposes, the level in the fair value hierarchy within which the fair value measurement is categorized is based on
the lowest level input that is significant to the overall fair value measurement.

54

The Company’s held-to-maturity securities, which are fixed income investments, are comprised of
obligations of U.S. government agencies, corporate debt securities and other interest bearing securities. These
held-to-maturity securities are recorded at amortized cost and are therefore not included in the Company’s
market value measurement disclosure. Money market funds are valued using quoted market prices with no
valuation adjustments applied. Accordingly, these securities are categorized in Level 1. The Company has no
other assets or liabilities for which fair value measurement is either required or has been elected to be applied,
other than the liability for contingent consideration recorded in connection with the acquisition of BioFlash
Partners, LLC (“BioFlash”) (See Note 13). The contingent consideration is valued using management’s estimates
of royalties to be paid to the former shareholders of BioFlash based on sales of the acquired assets. This valuation
is a Level 3 valuation as the primary inputs are unobservable. The following table provides a roll forward of the
fair value of the contingent consideration:

Balance at April 1, 2009 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Additions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Changes in Fair Value . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$ —
560,000
—

Balance at March 31, 2010 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$560,000

The following fair value hierarchy table presents information about each major category of the Company’s

assets and liabilities measured at fair value on a recurring basis as of March 31, 2010:

Fair value measurement at reporting date using:

Quoted prices in
active markets for
identical assets
(Level 1)

Significant other
observable
inputs
(Level 2)

Significant
unobservable
inputs
(Level 3)

Balance as of
March 31,
2010

Assets:

Money market funds . . . . . . . . . . . . . . . . . . .

$8,237,402

$8,237,402

There were no remeasurements to fair value during the year ended March 31, 2010 of financial assets and

liabilities that are not measured at fair value on a recurring basis.

Inventories

Inventories relate to the Company’s bioprocessing business. The Company values inventory at cost or, if

lower, fair market value using the first-in, first-out method. The Company reviews its inventories at least
quarterly and records a provision for excess and obsolete inventory based on its estimates of expected sales
volume, production capacity and expiration dates of raw materials, work-in process and finished products.
Expected sales volumes are determined based on supply forecasts provided by key customers for the next three to
twelve months. The Company writes down inventory that has become obsolete, inventory that has a cost basis in
excess of its expected net realizable value, and inventory in excess of expected requirements to cost of product
revenue. Manufacturing of bioprocessing finished goods is done to order and tested for quality specifications
prior to shipment.

A change in the estimated timing or amount of demand for the Company’s products could result in

additional provisions for excess inventory quantities on hand. Any significant unanticipated changes in demand
or unexpected quality failures could have a significant impact on the value of inventory and reported operating
results. During all periods presented in the accompanying financial statements, there has been no material
adjustments related to a revised estimate of inventory valuations.

55

Work-in-process and finished products inventories consist of material, labor, outside processing costs and

manufacturing overhead. Inventories consist of the following:

Raw Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Work-in-process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Finished products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$1,067,823
395,088
738,229

$1,400,408
791,465
221,354

Total

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$2,201,140

$2,413,227

As of March 31,

2010

2009

Accrued Liabilities

The Company estimates accrued liabilities by identifying services performed on the Company’s behalf,
estimating the level of service performed and determining the associated cost incurred for such service as of each
balance sheet date. Examples of estimated accrued expenses include: 1) Fees paid to contract manufacturers in
conjunction with the production of clinical materials. These expenses are normally determined through a contract
or purchase order issued by the Company; 2) Service fees paid to organizations for their performance in
conducting clinical trials. These expenses are determined by contracts in place for those services and
communications with project managers on costs which have been incurred as of each reporting date; 3)
Professional and consulting fees incurred with law firms, audit and accounting service providers and other third
party consultants. These expenses are determined by either requesting those service providers to estimate
unbilled services at each reporting date for services incurred, or tracking costs incurred by service providers
under fixed fee arrangements.

The Company has processes in place to estimate the appropriate amounts to record for accrued liabilities,

which principally involve the applicable personnel reviewing the services provided. In the event that the
Company does not identify certain costs which have begun to be incurred or the Company under or over-
estimates the level of services performed or the costs of such services, the reported expenses for that period may
be too low or too high. The date on which certain services commence, the level of services performed on or
before a given date, and the cost of such services are often judgmental. The Company makes these judgments
based upon the facts and circumstances known at the date of the financial statements.

Depreciation

Depreciation is calculated using the straight-line method over the estimated useful life of the asset as

follows:

Classification

Estimated Useful Life

Leasehold improvements . . .
Equipment . . . . . . . . . . . . . . .
Furniture and fixtures . . . . . .

Shorter of the term of the lease or estimated useful life
Three to five years
Three years

For depreciation of property and equipment, the Company expensed approximately $1,349,000, $1,077,000,
and $825,000 in fiscal 2010, 2009, and 2008, respectively. These amounts include depreciation of assets recorded
under capitalized lease agreements of approximately $34,000, $38,000, and $43,000 in 2010, 2009, and 2008,
respectively.

Earnings (Loss) Per Share

Basic earnings (loss) per share for the years ended March 31, 2010, 2009 and 2008 were computed on the
basis of the weighted average number of shares of common stock outstanding during the period. Diluted earnings

56

(loss) per share is computed on the basis of the weighted average number of shares of common stock plus the
effect of dilutive potential common shares outstanding during the period using the treasury stock method.
Dilutive potential common shares include outstanding stock options, restricted stock and warrants.

Basic and diluted weighted average shares outstanding were as follows:

Year Ended March 31,

2010

2009

2008

Weighted average common shares . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Dilutive common stock options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

30,752,041
—

30,957,957
332,276

30,834,491
486,506

Weighted average common shares, assuming dilution . . . . . . . . . . . . . . .

30,752,041

31,290,233

31,320,997

Diluted weighted average shares outstanding for the year ended March 31, 2010 does not include the impact
of 2,318,650 outstanding potential common shares for stock options as they would be anti-dilutive. Accordingly,
basic and diluted net losses per share are the same for the year ended March 31, 2010.

For years ended March 31, 2009 and 2008, options to purchase 938,000 and 443,000 shares were excluded

from the calculation of diluted earnings per share because the exercise prices of the stock options were greater
than or equal to the average price of the common shares.

Segment Reporting

The Company views its operations, makes decisions regarding how to allocate resources and manages the
business as one operating segment. As a result, the financial information disclosed herein represents all of the
material financial information related to the Company’s principal operating segment.

The following table represents the Company’s total revenue by geographic area (based on the location of the

customer):

Year ended March 31,

2010

2009

2008

US . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sweden . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Other . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

57%
36%
7%

60%
36%
4%

32%
61%
7%

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

100%

100%

100%

The following table represents the Company’s total revenue by product type:

Bioprocessing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SecreFlo® . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$10,304,727
—

$14,361,025
167,891

$16,321,065
2,266,311

Product revenue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Royalty and other revenue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$10,304,727
10,666,342

$14,528,916
14,832,605

$18,587,376
708,905

Total revenue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$20,971,069

$29,361,521

$19,296,281

Year ended March 31

2010

2009

2008

All of the Company’s assets are located in the United States for fiscal years ended March 31, 2010, 2009

and 2008.

57

Concentrations of Credit Risk and Significant Customers

Financial instruments that subject the Company to significant concentrations of credit risk primarily consist

of cash and equivalents, marketable securities and accounts receivable. Per the Company’s investment policy,
cash equivalents and marketable securities are invested in financial instruments with high credit ratings and
credit exposure to any one issue, issuer (with the exception of U.S. treasury obligations) and type of instrument is
limited. At March 31, 2010 and 2009, the Company had no investments associated with foreign exchange
contracts, options contracts or other foreign hedging arrangements.

Concentration of credit risk with respect to accounts receivable is limited to customers to whom the

Company makes significant sales. While a reserve for the potential write-off of accounts receivable is
maintained, the Company has not written off any significant accounts to date. To control credit risk, the
Company performs regular credit evaluations of its customers’ financial condition.

Revenue from significant customers as a percentage of the Company’s total revenue is as follows:

Years Ended March 31,

2010

2009

2008

Orencia® Royalties from Bristol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Bioprocessing Customer A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Bioprocessing Customer B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

43%
36%
1%

46%
36%
4%

—
61%
14%

Significant accounts receivable balances as a percentage of the Company’s total trade accounts receivable

and royalties receivable balances are as follows:

Orencia® Royalties from Bristol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Bioprocessing Customer B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Bioprocessing Customer C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

As of March 31,

2010

80%
2%
13%

2009

70%
12%
—

Business Combinations

Amounts paid for acquisitions are allocated to the assets acquired and liabilities assumed, if any, based on

their fair values at the dates of acquisition. The fair value of identifiable intangible assets is based on detailed
valuations that use information and assumptions determined by management. Any excess of purchase price over
the fair value of the net tangible and intangible assets acquired is allocated to goodwill. The fair value of
contingent consideration includes estimates and judgments made by management regarding the extent of
royalties to be earned in excess of the defined minimum royalties. Management will update these estimates and
the related fair value of contingent consideration at each reporting period.

Goodwill and Intangible Assets

Intangible assets are amortized over their useful lives using the estimated economic benefit method, as

applicable.

Goodwill is not amortized. Instead goodwill is reviewed for impairment at least annually. There was no

evidence of impairment to goodwill for fiscal year 2010.

Intangible assets and their related useful lives are reviewed at least annually to determine if any adverse
conditions exist that would indicate the carrying value of these assets may not be recoverable. More frequent
impairment assessments are conducted if certain conditions exist, including: a change in the competitive

58

landscape, any internal decisions to pursue new or different technology strategies, a loss of a significant
customer, or a significant change in the market place including changes in the prices paid for our products or
changes in the size of the market for our products. An impairment results if the carrying value of the asset
exceeds the estimated fair value of the asset based on the sum of the future undiscounted cash flows expected to
result from the use and disposition of the asset. If the estimate of an intangible asset’s remaining useful life is
changed, the remaining carrying amount of the intangible asset is amortized prospectively over the revised
remaining useful life. There were no indicators of impairment in fiscal year 2010.

Stock Based Compensation

The Company uses the Black-Scholes option pricing model to calculate the fair value of share-based awards

on the grant date. The following assumptions are used in calculating the fair value of share-based awards:

Expected term—The expected term of options granted represents the period of time for which the options
are expected to be outstanding and is derived from the Company’s historical stock option exercise experience and
option expiration data. The expected term is presumed to be the midpoint between the vesting date and the end of
the contractual term. In addition, for purposes of estimating the expected term, the Company has aggregated all
individual option awards into one group as the Company does not expect substantial differences in exercise
behavior among its employees.

Expected volatility—The expected volatility is a measure of the amount by which the Company’s stock
price is expected to fluctuate during the expected term of options granted. The Company determines the expected
volatility based primarily upon the historical volatility of the Company’s common stock over a period
commensurate with the option’s expected term, exclusive of any events not reasonably anticipated to recur over
the option’s expected term.

Risk-free interest rate—The risk-free interest rate is the implied yield available on U.S. Treasury zero-

coupon issues with a remaining term equal to the option’s expected term on the grant date.

Expected dividend yield—The Company has never declared or paid any cash dividends on any of its capital

stock and does not expect to do so in the foreseeable future. Accordingly, the Company uses an expected
dividend yield of zero to calculate the grant-date fair value of a stock option.

Estimated forfeiture rates—The Company has applied, based on an analysis of its historical forfeitures,
annual forfeiture rates of 8% for awards granted to non-executive level employees and 3% for awards granted to
executive level employees to all unvested stock options as of March 31, 2010. The Company reevaluates this
analysis periodically and adjusts these estimated forfeiture rates as necessary. Ultimately, the Company will only
recognize expense for those shares that vest.

Recent Accounting Pronouncements

In October 2009, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update

(“ASU”) No. 2009-13, “Multiple-Deliverable Arrangements—a consensus of the FASB Emerging Issues Task
Force” (“ASU 2009-13”). This ASU establishes the accounting and reporting guidance for arrangements under
which a vendor will perform multiple revenue-generating activities. Specifically, the provisions of this update
address how to separate deliverables and how to measure and allocate arrangement consideration to one or more
units of accounting. This update is effective prospectively for revenue arrangements entered into or materially
modified in fiscal years beginning on or after June 15, 2010. Early adoption is permitted. The Company has not
yet completed its evaluation of ASU 2009-13, but does not currently believe that adoption will have a material
impact on its results of operations, financial position or cash flows.

59

In January 2010, the FASB issued ASU No. 2010-06, “Improving Disclosures about Fair Value

Measurements“ (“ASU 2010-06”). This ASU requires new disclosures and clarifies some existing disclosure
requirements about fair value measurements codified within ASC 820, “Fair Value Measurements and
Disclosures,” including significant transfers into and out of Level 1 and Level 2 investments of the fair value
hierarchy. ASU 2010-06 also requires additional information in the roll forward of Level 3 investments including
presentation of purchases, sales, issuances, and settlements on a gross basis. Further clarification for existing
disclosure requirements provides for the disaggregation of assets and liabilities presented, and the enhancement
of disclosures around inputs and valuation techniques. This update is effective for the first interim or annual
reporting period beginning after December 15, 2009, except for the additional information in the roll forward of
Level 3 investments. Those disclosures are effective for fiscal years beginning after December 15, 2010, and for
interim reporting periods within those fiscal years. The Company adopted ASU 2010-06 in January 2010. The
adoption of this update did not have a material impact on its results of operations, financial position or cash
flows.

In April 2010, the FASB issued ASU No. 2010-17, “Milestone Method of Revenue Recognition—a

consensus of the FASB Emerging Issues Task Force” (“ASU 2010-17”). This ASU provides guidance on defining
a milestone and determining when it may be appropriate to apply the milestone method of revenue recognition
for research and development transactions. ASU 2010-17 is effective on a prospective basis for milestones
achieved in fiscal years, and interim periods within those years, beginning on or after June 15, 2010. Early
adoption is permitted. The Company has not yet completed its evaluation of ASU 2010-17, but does not currently
believe that adoption will have a material impact on its results of operations, financial position or cash flows.

3.

Income Taxes

The tax benefit of ($834,766) for the year ended March 31, 2010 is comprised of a current benefit for
federal income taxes of ($834,766). The benefit for federal income taxes is due to the “Worker, Homeownership,
and Business Assistance Act of 2009” (the “Act”) that was enacted in November 2009. Among other things, the
Act suspended the limitation on the use of net operating losses to offset alternative minimum tax liabilities. The
Company paid a total of approximately $835,000 of alternative minimum taxes in the fiscal years ended
March 31, 2009 and 2008 combined. The Company expects to receive a refund of approximately $835,000 upon
filing its tax return for the year ended March 31, 2010. This refundable tax amount is included in prepaid
expenses and other current assets on the balance sheet at March 31, 2010. For the year ended March 31, 2009, the
tax provision of $26,699 is comprised of a current provision for federal income taxes of $29,557 and a current
benefit for state income taxes of ($2,858). For the year ended March 31, 2008, the tax provision of $827,471 is
comprised of a current provision for federal income taxes of $736,805 and a current provision for state income
taxes of $90,666.

At March 31, 2010, the Company had net operating loss carryforwards of approximately $63,903,000 and
business tax credits carryforwards of approximately $2,118,000 available to reduce future federal income taxes,
if any. Additionally, at March 31, 2010, we had net operating loss carryforwards of approximately $3,061,000
and business tax credits carryforwards of approximately $5,615,000 available to reduce future state income taxes,
if any. The net operating loss and business tax credits carryforwards will continue to expire at various dates
through March 2030. The net operating loss and business tax credit carryforwards are subject to review and
possible adjustment by the Internal Revenue Service and may be limited in the event of certain changes in the
ownership interest of significant stockholders.

60

Our deferred tax assets consist of the following:

As of March 31,

2010

2009

Temporary timing differences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Net operating loss carryforwards . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tax business credits carryforwards . . . . . . . . . . . . . . . . . . . . . . . . . . .

$ 4,700,000
21,919,000
4,157,000

$ 4,716,000
19,957,000
4,646,000

Total deferred tax assets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Valuation allowance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

30,776,000
(30,776,000)

29,319,000
(29,319,000)

Net deferred tax asset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$

—

$

—

At March 31, 2010 and 2009, a full valuation allowance has been provided against the deferred tax assets, as

it is uncertain if the Company will realize the benefits of such deferred tax assets.

The reconciliation of the federal statutory rate to the effective income tax rate for the years ended March 31,

2010, 2009 and 2008 is as follows:

Years Ended March 31,

2010

2009

2008

Income (loss) before income taxes . . . . . . . .

$(4,898,610)

% $ 5,772,727

% $ 37,933,985

%

Expected tax (recovery) at statutory rate . . .
Adjustments due to:
State income and franchise taxes . . . . . . . . .
Utilization of loss carryforwards and

business tax credits . . . . . . . . . . . . . . . . . .
Alternative minimum tax . . . . . . . . . . . . . . .
Permanent differences . . . . . . . . . . . . . . . . .
Change in valuation allowance . . . . . . . . . .

(1,665,527)

(34.0)% 1,962,727

34.0% 12,897,555

34.0%

(80,151)

(1.6)%

287,822

5.0% 1,620,725

4.3%

(934,659)

—
255,766
1,589,805

(19.1)% (1,891,597)
96,540
207,508
(636,301)

—
5.2%
32.5%

(32.8)% (13,987,955)
732,817
191,459
(11.0)% (627,130)

1.7%
3.6%

(36.9)%
1.9%
0.5%
(1.6)%

(Benefit) provision for income taxes . . . . . .

$ (834,766)

(17.0)% $

26,699

0.5% $

827,471

2.2%

At March 31, 2010, 2009 and 2008, the Company had no material unrecognized tax benefits.

The Company recognizes interest and penalties related to uncertain tax positions in income tax expense. No

interest and penalties have been recognized by the Company to date.

Fiscal years 2006 through 2010 are subject to examination by the federal and state taxing authorities. There

are no income tax examinations currently in process.

4.

Stockholders’ Equity

Common Stock and Warrants

At March 31, 2010, the Company has reserved 2,893,859 shares of common stock pursuant to the Plans. As

discussed in Note 11 below, on April 6, 2007, the Company issued warrants to an individual at Scripps to
purchase up to 150,000 shares of common stock. The warrants have a 7-year term and are exercisable based on
performance criteria as detailed in the warrant agreement. At this time, the Company does not believe that the
performance criteria are probable of being achieved in the near future.

61

Shareholder Rights Plan

In March 2003, the Company adopted a Shareholder Rights Agreement (the “Rights Agreement”). Under
the Rights Agreement, the Company distributed certain rights to acquire shares of the Company’s Series A junior
participating preferred stock (the “Rights”) as a dividend for each share of common stock held of record as of
March 17, 2003. Each share of common stock issued after the March 17, 2003 record date has an attached Right.
Under certain conditions involving an acquisition by any person or group of 15% or more of the common stock
(20% in the case of a certain stockholder) (“the 15% holder”), each Right permits the holder (other than the 15%
holder) to purchase common stock having a value equal to twice the exercise price of the Right, upon payment of
the exercise price of the Right. In addition, in the event of certain business combinations after an acquisition by a
person or group of 15% or more of the common stock (20% in the case of a certain stockholder), each Right
entitles the holder (other than the 15% holder) to receive, upon payment of the exercise price, common stock
having a value equal to twice the exercise price of the Right. The Rights have no voting privileges and, unless
and until they become exercisable, are attached to, and automatically trade with, the Company’s common stock.
The Rights will terminate upon the earlier of the date of their redemption or March 2013.

Stock Based Compensation

For fiscal years ended March 31, 2010, 2009 and 2008, the Company recorded stock-based compensation

expense of approximately $1,007,000, $823,000 and $524,000, respectively, for stock options granted under the
Second Amended and Restated 2001 Repligen Corporation Stock Plan (the “2001 Plan”).

The 2001 Plan allows for the granting of incentive and nonqualified options and restricted stock and other
equity awards to purchase shares of common stock. Incentive options granted to employees under the 2001 Plan
generally vest over a four to five-year period, with 20%-25% vesting on the first anniversary of the date of grant
and the remainder vesting in equal yearly installments thereafter. Nonqualified options issued to non-employee
directors and consultants under the 2001 Plan generally vest over one year. Options granted under the 2001 Plan
have a maximum term of ten years from the date of grant and generally, the exercise price of the stock options
equals the fair market value of the Company’s common stock on the date of grant. At March 31, 2010, options to
purchase 2,318,650 shares were outstanding under the 2001 Plan and the 1992 Repligen Corporation Stock
Option Plan (collectively with the 2001 Plan, the “Plans”). At March 31, 2010, 575,209 shares were available for
future grant under the 2001 Plan.

The Company uses the Black-Scholes option pricing model to calculate the fair value of share-based awards

on the grant date. The fair value of share-based awards granted during the fiscal years ended March 31, 2010,
2009 and 2008 were calculated using the following estimated weighted-average assumptions:

Years Ended March 31,

2010

2009

2008

Expected term (years) . . . . . . . . . . . . . . . . . . . . . . . . .
Volatility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Risk-free interest rate . . . . . . . . . . . . . . . . . . . . . . . . .
Expected dividend yield . . . . . . . . . . . . . . . . . . . . . . .

6.5

6.5
58.12% - 65.14% 60.47% - 64.07% 64.46% - 76.85%
2.81% - 4.97%
1.88% - 3.71%
2.54% - 3.14%
—
—
—

6.5

The Company recognizes stock-based compensation expense on a straight-line basis over the requisite
service period based upon options that are ultimately expected to vest, and accordingly, such compensation
expense has been adjusted by an amount of estimated forfeitures.

62

Information regarding option activity for the year ended March 31, 2010 under the Plans is summarized

below:

Weighted-
Average
Exercise
Price Per
Share

Weighted-
Average
Remaining
Contractual
Term
(in years)

Aggregate
Intrinsic
Value

Options outstanding at April 1, 2009 . . . . . . . . . . . . . . . . . . . .
Granted . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Exercised . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Forfeited/Cancelled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Options
Outstanding

2,213,550
247,000
(20,100)
(121,800)

Options outstanding at March 31, 2010 . . . . . . . . . . . . . . . . . .

2,318,650

$4.37
4.55
2.69
4.99

$4.37

Options exercisable at March 31, 2010 . . . . . . . . . . . . . . . . . . .

1,371,250

$4.09

Vested and expected to vest at March 31, 2010 (1)

. . . . . . . . .

2,194,544

$4.35

6.14

4.61

6.02

$1,174,676

$1,020,881

$1,147,354

(1) This represents the number of vested options as of March 31, 2010 plus the number of unvested options
expected to vest as of March 31, 2010 based on the unvested outstanding options at March 31, 2010
adjusted for estimated forfeitures.

The aggregate intrinsic value in the table above represents the total pre-tax intrinsic value (the difference

between the closing price of the common stock on March 31, 2010 of $4.06 and the exercise price of each
in-the-money option) that would have been received by the option holders had all option holders exercised their
options on March 31, 2010.

The weighted average grant date fair value of options granted during the fiscal years ended March 31, 2010
and 2009 was $2.71 and $3.17, respectively. The total fair value of stock options that vested during fiscal years
ended March 31, 2010, 2009 and 2008 was approximately $1,067,000, $655,000 and $494,000, respectively. The
total intrinsic value of options exercised during the years ended March 31, 2010, 2009 and 2008 was $43,875,
$418,366 and $1,672,260, respectively, determined as of the date of exercise. The Company received $53,991,
$401,759 and $637,655 from stock option exercises during the years ended March 31, 2010, 2009 and 2008,
respectively.

As of March 31, 2010, there was $1,919,119 of total unrecognized compensation cost related to unvested

share-based awards. This cost is expected to be recognized over a weighted average remaining requisite service
period of 3.11 years. The Company expects 823,294 in unvested options to vest over the next five years.

5. Commitments and Contingencies

Lease Commitments

In 2001, the Company entered into a ten-year lease agreement for approximately 25,000 square feet of space

located in Waltham, Massachusetts to be used for its corporate headquarters, manufacturing, research and
development, and marketing and administrative operations. In connection with this lease agreement, the
Company issued a letter of credit in the amount of $200,000 to the lessor. The letter of credit is collateralized by
a certificate of deposit held by the bank that issued the letter of credit. The certificate of deposit is classified as
restricted cash in the accompanying balance sheet as of March 31, 2010 and 2009. In 2007, the Company entered
into a five-year lease agreement for approximately 2,500 square feet of space in Waltham, Massachusetts to
provide for expanded manufacturing operations. Adjacent to this space, the Company entered into a two-year
lease in 2008 for approximately 7,350 square feet of additional space to be used for expanded manufacturing and
administrative operations.

63

In fiscal 2006, Repligen entered into a capital lease agreement to provide the Company with manufacturing

equipment over a five-year period. In fiscal 2005, the Company entered into two capital lease agreements to
provide us with two pieces of office equipment for approximately $33,000. The lease terms were three and five
years beginning in June and October of 2004, respectively. As of March 31, 2010, the Company has no
remaining capital lease obligations.

Obligations under non-cancelable operating leases, including the facility leases discussed above, as of

March 31, 2010 are as follows:

Years Ending

Operating Leases

March 31, 2011 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
March 31, 2012 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
March 31, 2013 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$ 572,079
423,948
9,264

Minimum lease payments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$1,005,291

Rent expense charged to operations under operating leases was approximately $689,000, $631,000 and
$512,000 for the years ended March 31, 2010, 2009 and 2008, respectively. As of March 31, 2010, 2009 and
2008, the Company had a deferred rent liability of $64,000, $100,600 and $118,900, respectively related to the
escalating rent provisions for the Waltham headquarters.

Licensing and Research Agreements

The Company licenses certain technologies that are, or may be, incorporated into its technology under
several agreements and also has entered into several clinical research agreements which require the Company to
fund certain research projects. Generally, the license agreements require the Company to pay annual maintenance
fees and royalties on product sales once a product has been established using the technologies.

In October 2009, the Company entered into an exclusive worldwide commercial license agreement with

Families of Spinal Muscular Atrophy (see Note 12). The initial license fee of $500,000 and a related sublicense
fee of $175,000 have been charged to research and development expenses in fiscal 2010. In April 2007 the
Company entered into an exclusive license agreement with the Scripps Research Institute (see Note 11). The
initial license fee under this agreement aggregated $600,000 in a combination of cash and Company common
stock and was charged to research and development expenses in fiscal 2008. The Company has recorded research
and development expenses associated with license agreements of approximately $643,000, $326,000, and
$681,000 for fiscal years 2010, 2009 and 2008, respectively.

Purchase Orders, Supply Agreements and Other Contractual Obligations

In the normal course of business, the Company has entered into purchase orders and other agreement with

manufacturers, distributors and others. Outstanding obligations at March 31, 2010 are approximately $1,933,000
where approximately $1,908,000 is expected to be completed within one year and the remaining amount to be
substantially completed within two years.

64

6.

Prepaid Expenses and Other Current Assets

Prepaid expenses and other current assets consist of the following:

As of March 31,

2010

2009

Interest receivable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Prepaid taxes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Prepaid insurance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Clinical and research expenses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Equipment and services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Other . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$ 223,290
882,439
169,829
80,031
109,358
14,160

$354,416
182,830
155,321
133,133
93,725
14,160

Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$1,479,107

$933,585

7. Accrued Liabilities

Accrued liabilities consist of the following:

As of March 31,

2010

2009

Employee compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Research and development
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Royalty and license fees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Unearned revenue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Professional fees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Other accrued expenses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Other current liabilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$1,285,172
787,267
881,900
306,794
216,086
133,554
55,362

$1,040,529
769,793
269,850
125,000
94,572
110,059
216,538

Total

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$3,666,135

$2,626,341

8. Employee Benefit Plan

The Repligen Corporation 401(k) Savings and Retirement Plan (the “401(k) Plan”) is a qualified defined
contribution plan in accordance with Section 401(k) of the Internal Revenue Code. All employees over the age of
21 are eligible to make pre-tax contributions up to a specified percentage of their compensation. Under the
401(k) Plan, the Company may, but is not obligated to match a portion of the employees’ contributions up to a
defined maximum. The match is calculated on a calendar year basis. The Company matched approximately
$117,000, $85,278, and $56,647 for the fiscal years ended March 31, 2010, 2009, and 2008 respectively.

9. Related Party Transactions

The Company paid Dr. Alexander Rich, Chairman of the Board of Directors, $47,400 and $43,200 in fiscal

years 2009 and 2008, respectively, per a consulting agreement that automatically extended for successive
one-year terms unless terminated by either party at least 90 days prior to the next anniversary date. Effective
January 2009, this consulting agreement was terminated and Dr. Rich is now paid a monthly retainer similar to
the Company’s other directors. Dr. Rich received no additional cash compensation for attendance at Board of
Directors meetings or otherwise as director.

The Company paid Dr. Paul Schimmel, former Co-Chairman of the Board of Directors, $32,800 in fiscal
year 2008 pursuant to a consulting agreement. This agreement automatically extended for successive one-year
terms unless terminated by either party at least 90 days prior to the next anniversary date. Dr. Schimmel retired
from the Board of Directors as of the Company’s annual meeting in September 2007, and accordingly, the
consulting agreement with Dr. Schimmel was terminated at that time. Dr. Schimmel received no additional cash
compensation for attendance at Board of Directors meetings or otherwise as director.

65

10. Legal Proceedings

ImClone Systems

In May 2004, Repligen and the Massachusetts Institute of Technology (“MIT”) filed an action in the United

States District Court for the District of Massachusetts against ImClone Systems, Incorporated (“ImClone”) for
infringement of U.S. Patent No. 4,663,281 (“the ‘281 patent”) based on ImClone’s manufacture and sale of
Erbitux®. The ‘281 patent, which covers the use of certain genetic elements that increase protein production in a
mammalian cell, is assigned to MIT and exclusively licensed to Repligen.

On September 10, 2007, Repligen and MIT entered into a settlement agreement (the “ImClone Settlement”)

with ImClone relating to the lawsuit against ImClone for infringement of the ‘281 patent. Pursuant to the
ImClone Settlement, ImClone made a payment of $65 million to Repligen and MIT that resulted in net proceeds
to Repligen of $40.17 million, as follows:

Gross proceeds from Settlement Agreement . . . . . . . . . . . . . . . . . . . . . . . . . .
Less: Amounts paid to MIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Less: Legal fees and other costs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$ 65,000,000
(11,000,000)
(13,830,000)

Net gain on litigation settlement

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$ 40,170,000

The ImClone Settlement served as the basis for the Company and MIT to dismiss the lawsuit against
ImClone and for the Company to grant ImClone a non-exclusive sublicense to the ‘281 patent and certain other
intellectual property. There are no further obligations to the Company with respect to the sublicenses. The net
gain on litigation settlement was recorded as a separate component of operating expenses in the statement of
operations in fiscal 2008.

Bristol-Myers Squibb Company (“Bristol”)

In January 2006, Repligen and the University of Michigan jointly filed a complaint against Bristol in the
United States District Court for the Eastern District of Texas for infringement of U.S. Patent No. 6,685,941 (“the
‘941 patent”) for the commercial sale of Orencia®. The ‘941 patent, entitled “Methods of Treating Autoimmune
Disease via CTLA4-Ig,” covers methods of using CTLA4-Ig to treat rheumatoid arthritis, as well as other
therapeutic methods. Repligen has exclusive rights to this patent from its owners, the University of Michigan and
the U.S. Navy. In February 2006, Bristol answered the complaint and counterclaimed seeking a declaratory
judgment that the ‘941 patent is invalid and unenforceable and that Bristol does not infringe the patent.

On April 7, 2008, Repligen and the University of Michigan entered into a settlement agreement (the “Bristol

Settlement”) with Bristol relating to the lawsuit against Bristol for infringement of the ‘941 patent. Pursuant to
the Bristol Settlement, Bristol made an initial payment of $5 million to Repligen. The settlement further provides
for Bristol to pay royalties on the United States net sales of Orencia® for any clinical indication at a rate of 1.8%
for the first $500 million of annual net sales, 2.0% for the next $500 million of annual net sales and 4% of annual
net sales in excess of $1 billion for each year from January 1, 2008 until December 31, 2013. The Bristol
Settlement served as the basis for Repligen and the University of Michigan to dismiss the lawsuit against Bristol
and for Repligen and the University of Michigan to grant to Bristol an exclusive worldwide license to the ‘941
patent and certain other intellectual property.

Pursuant to the Bristol Settlement, the Company recognized royalty revenue in fiscal years 2010 and 2009

of approximately $8,980,000 and $13,383,000, respectively. The $13,383,000 recognized in fiscal 2009 included
an initial $5.0 million royalty payment, $1.3 million in royalties for sales of Orencia® from January 1, 2008 to
March 31, 2008, as well as $7.1 million for sales in fiscal year 2009 (see Note 2).

Repligen must also remit to the University of Michigan 15% of all royalty revenue received from Bristol,
after deducting certain legal and other costs incurred related to the Bristol Settlement. The Company incurred

66

approximately $6.1 million in such legal costs. Royalty expense for fiscal years 2010 and 2009 was
approximately $1,347,000 and $1,091,000, respectively. This operating expense has been included on the
statements of operations under the line item “Cost of royalty and other revenue.”

11. Scripps Agreements

License Agreement

On April 6, 2007, the Company entered into an exclusive worldwide commercial license agreement

(“License Agreement”) with The Scripps Research Institute (“Scripps”). Pursuant to the License Agreement, the
Company obtained a license to use, commercialize and sublicense certain patented technology and improvements
thereon, owned or licensed by Scripps, relating to compounds which may have utility in treating Friedreich’s
ataxia, an inherited neurodegenerative disease. Research in tissues derived from patients, as well as, in mice,
indicates that the licensed compounds increase production of the protein frataxin, which suggests potential utility
of these compounds in slowing or stopping progression of the disease. There are currently no approved
treatments for Friedreich’s ataxia in the U.S.

Pursuant to the License Agreement, the Company agreed to pay Scripps an initial license fee of $300,000,

certain royalty and sublicense fees and, in the event that the Company achieves specified developmental and
commercial milestones, certain additional milestone payments. Total future milestone payments, were all
milestones achieved, would be approximately $4.3 million. In addition, the Company issued Scripps and certain
of its designees 87,464 shares of the Company’s common stock which had a value of $300,000 on the date of
issuance. The Company recorded the initial license payment and the value of the shares issued as research and
development costs in the statements of operations in fiscal 2008.

In connection with the License Agreement, the Company issued warrants to an individual at Scripps to
purchase up to 150,000 shares of common stock. The warrants have a 7-year term and are exercisable based on
performance criteria as detailed in the warrant agreement. No expense has been recorded related to these
warrants through March 31, 2010, as none of the performance criteria have been achieved. At this time, the
Company does not believe that the performance criteria are probable of being achieved in the near future.

The License Agreement with Scripps expires or may be terminated (i) when all of the royalty obligations

under the License Agreement expire; (ii) at any time by mutual written consent; (iii) by Scripps if the Company
(a) fails to make payments under the License Agreement, (b) fails to achieve certain developmental and
commercial objectives, (c) becomes insolvent, (d) is convicted of a felony relating to the manufacture, use or sale
of the licensed technology, or (e) defaults in its performance under the License Agreement; or (iv) by the
Company upon 90 days written notice.

Research Funding and Option Agreement

On October 26, 2007, the Company entered into a research funding and option agreement (“Funding
Agreement”) with Scripps to fund a research program for the research and development of compounds that may
have utility in the treatment of Friedreich’s ataxia. Pursuant to the Funding Agreement, the Company is required
to fund approximately $35,000 per quarter which is recorded as research and development expenses. In exchange
for funding the research, Scripps will grant an exclusive option to the Company to acquire a sole, worldwide
license, including the right to sublicense, manufacture and sell products, and services that result from the
research program. There are no guaranties or warranties that products or services may result from the research
program and the Company has therefore ascribed no value to the license. The Funding Agreement expires or may
be terminated (i) when all of the royalty obligations under the Funding Agreement expire; (ii) at any time by
mutual written consent; (iii) by Scripps if the Company (a) fails to make payments under the Funding
Agreement, (b) fails to achieve certain developmental and commercial objectives, (c) becomes insolvent, (d) is
convicted of a felony relating the manufacture, use or sale of the licensed technology, or (e) defaults in its
performance under the Funding Agreement; or (iv) by the Company upon 90 days written notice.

67

The Company made payments to Scripps of approximately $123,000, $133,000 and $105,000 for fiscal

years 2010, 2009 and 2008, respectively, in connection with the Funding Agreement, as amended.

12. FSMA License Agreement

On October 22, 2009, the Company entered into an exclusive worldwide commercial license agreement
(“FSMA License Agreement”) with Families of Spinal Muscular Atrophy (“FSMA”). Pursuant to the FSMA
License Agreement, the Company obtained an exclusive license to develop and commercialize certain patented
technology and improvements thereon, owned or licensed by FSMA, relating to compounds which may have
utility in treating spinal muscular atrophy (“SMA”). SMA is an inherited neurodegenerative disease in which a
defect in the survival motor neuron gene (“SMN”) results in low levels of the protein SMN and leads to
progressive damage to motor neurons, loss of muscle function and, in many patients, early death.

Pursuant to the License Agreement, the Company paid FSMA an initial license fee of $500,000 and a
related sublicense fee of $175,000 which have been recorded as research and development expense in the
statements of operations in fiscal 2010. If all milestones are achieved, total financial obligations under this
agreement, including milestone payments, sublicense fees, and other charges, could total approximately
$16,000,000. Given the uncertain nature of such a development program, the likelihood that products or services
will result from the research program is not known at this time. The Company has therefore ascribed no value to
the license or the related liability.

The License Agreement with FSMA expires or may be terminated (i) on the later of: (a) when all related

patents have expired or been abandoned, or (b) 10 years following the first commercial sale of a licensed
product; (ii) by FSMA if the Company (a) fails to make payments under the License Agreement, (b) fails to use
commercially reasonable efforts towards development and commercial objectives, (c) fails to maintain the
required insurance or becomes insolvent, or (d) defaults in its performance under the License Agreement; or
(iii) by the Company upon 30 days written notice.

13. BioFlash Acquisition

On January 29, 2010, the Company acquired the assets of BioFlash including a technology platform for the

production of pre-packed, “plug and play” chromatography columns for total consideration transferred of $2.6
million. This patented technology enables economical production of chromatography columns in a format that is
ready for use in the production of a broad range of biopharmaceuticals including monoclonal antibodies, vaccines
and recombinant proteins. The terms of the acquisition include an upfront payment of $1.8 million, a milestone
payment of $300,000 payable the earlier of (i) the date on which Repligen receives an acknowledgment executed
by a specific customer or (ii) the second anniversary of the acquisition date, and future royalties based on product
sales.

The Company will manufacture and sell these pre-packed columns under the brand name OpusTM. OpusTM

pre-packed chromatography columns have the potential to improve the speed of process development and reduce
the cost of biopharmaceutical manufacturing by decreasing the time associated with set-up, cleaning and
validation of traditional manufacturing technologies.

Consideration Transferred

The Company has accounted for the acquisition of the assets of BioFlash as the purchase of a business under

U.S. Generally Accepted Accounting Principles. Under the acquisition method of accounting, the assets of
BioFlash were recorded as of the acquisition date, at their respective fair values, and consolidated with those of
Repligen. The purchase price is based upon estimates of the fair value of assets acquired. The preparation of the
valuation required the use of significant assumptions and estimates. Critical estimates included, but were not
limited to, future expected cash flows, including projected revenues and expenses, and the applicable discount

68

rates. These estimates were based on assumptions that the Company believes to be reasonable. However, actual
results may differ from these estimates. The Company incurred transaction costs of $90,707 associated with the
acquisition of the assets of BioFlash.

The total consideration transferred is as follows:

Cash consideration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Liability for additional payment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Estimated fair value of contingent consideration . . . . . . . . . . . . . . . . . . . . . . . .

$1,780,000
300,000
560,000

Total consideration transferred . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$2,640,000

The fair value of contingent consideration was determined based upon a probability weighted analysis of
expected future royalty payments (and the fair value of a time-based additional payment) to be made to former
shareholders of BioFlash. The liability for contingent consideration is included in long-term liabilities on the
balance sheet at March 31, 2010 and will be remeasured at each reporting period until the contingency is
resolved.

Allocation of Consideration Transferred

The following chart summarizes the allocation of consideration transferred:

Intangible assets subject to amortization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Goodwill
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$1,430,000
994,000
216,000

Total

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$2,640,000

The excess of the consideration transferred over the fair value of net tangible assets acquired was allocated

to specific intangible asset categories as follows:

Amortizable intangible assets

Technology – developed . . . . . . . . . . . . . . . . . . . . .
Patents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Customer relationships . . . . . . . . . . . . . . . . . . . . . .

Goodwill

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Amount
Assigned

Amortization
Period

Accumulated
Amortization
March 31, 2010

$ 760,000
240,000
430,000

$1,430,000
994,000

8 years
8 years
8 years

$15,834
5,000
8,958

$29,792

The Company believes that the intangible assets are recorded at fair value at the date of acquisition and do

not exceed the amount a third party would pay for the assets. The Company used the income approach to
determine the fair value of the amortizable intangible assets. The Company expects to record amortization
expense of $178,750 in each of the next five years.

Various factors contributed to the establishment of goodwill, including the expected business plans and

opportunities to introduce future products to BioFlash’s customer base.

69

14. Valuation and Qualifying Accounts

Balance at
Beginning of
Period

Reversal
without
Utilization

Balance at
End of
Period

Additions

Allowance for Doubtful Accounts:
2008 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2009 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2010 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

$10,000
$10,000
$10,000

$5,000
—
—

$5,000
—
—

$10,000
$10,000
$10,000

15. Selected Quarterly Financial Data (Unaudited)

The following table contains statements of operations information for each quarter of fiscal 2010 and 2009.

The Company believes that the following information reflects all normal recurring adjustments necessary for a
fair presentation of the information for the periods presented. The operating results for any quarter are not
necessarily indicative of results for any future period.

Revenue:

Q4 FY10 Q3 FY10 Q2 FY10 Q1 FY10 Q4 FY09 Q3 FY09 Q2 FY09 Q1 FY09

(in thousands, except per share amounts)

Product revenue . . . . . . . . . . . . . . $ 2,225 $ 2,865 $ 2,742 $ 2,473 $ 2,558 $ 3,294 $ 2,984 $ 5,693
7,967
Royalty and other revenue . . . . . .

2,724

2,036

2,752

2,679

2,647

2,588

2,106

Total revenue . . . . . . . . . . . . . . . . . . . .

4,872

5,617

5,421

5,061

4,594

6,018

5,090

13,660

Operating expenses:

Cost of product revenue . . . . . . .
Cost of royalty and other

revenue . . . . . . . . . . . . . . . . . .
. . . . .

Research and development
Selling, general and

administrative . . . . . . . . . . . . .

Total operating expenses . . . . . . . . . . .

Income (loss) from operations . . . . . .
Investment income . . . . . . . . . . . . . . .
Interest income (expense) . . . . . . . . . .

Income (loss) before taxes . . . . . . . . .
Income tax (benefit) provision . . . . . .

885

1,085

918

1,271

1,342

1,287

1,211

1,846

345
3,453

1,952

6,635

(1,763)
134
—

(1,629)
—

343
3,845

1,714

6,987

341
3,479

1,889

6,627

318
3,383

1,517

6,489

(1,370)
187
(1)

(1,206)
227

(1,428)
322
(1) —

(1,184)

(980)

(835) —

(1,106)
—

270
4,645

1,552

7,809

(3,215)
375
(1)

(2,841)
148

286
3,579

1,404

6,556

(538)
473
(1)

(66)
84

210
2,463

1,530

5,414

(324)
515
1

192
(50)

325
2,084

1,447

5,702

7,958
533
(2)

8,489
(210)

Net income (loss)

. . . . . . . . . . . . . . . . $ (1,629) $ (349) $ (980) $ (1,106) $ (2,693) $

18 $

142 $ 8,279

Earning per share:

Basic . . . . . . . . . . . . . . . . . . . . . . $ (0.05) $ (0.01) $ (0.03) $ (0.04) $ (0.09) $

0.00 $

0.00 $

0.27

Diluted . . . . . . . . . . . . . . . . . . . . . $ (0.05) $ (0.01) $ (0.03) $ (0.04) $ (0.09) $

0.00 $

0.00 $

0.26

Weighted average shares outstanding:
Basic . . . . . . . . . . . . . . . . . . . . . .

30,752

30,759

30,746

30,742

30,698

30,809

31,173

31,153

Diluted . . . . . . . . . . . . . . . . . . . . .

30,752

30,759

30,746

30,742

30,962

31,025

31,556

31,585

70

Corporate Information 

Board of Directors

Glenn L. Cooper, M.D.
Retired/Private Investor 

Karen A. Dawes
President  
Knowledgeable Decisions, LLC 

Alfred L. Goldberg, Ph.D. 
Professor of Cell Biology  
Harvard Medical School 

Earl Webb Henry, M.D.
Chief Medical Officer 
inVentiv Clinical Solutions 

Walter C. Herlihy, Ph.D.
President and Chief Executive Officer 
Repligen Corporation

Alexander Rich, M.D., Chairman
Sedgwick Professor of Biophysics 
Department of Biology 
Massachusetts Institute of Technology

Thomas F. Ryan, Jr.
Retired/Private Investor

Corporate Officers 

Walter C. Herlihy, Ph.D. 
President and Chief Executive Officer

William J. Kelly 
Chief Financial Officer

James R. Rusche, Ph.D. 
Sr. Vice President, 
Research and Development

Daniel P. Witt, Ph.D. 
Vice President, Operations

Transfer Agent and Registrar

Annual Meeting

American Stock Transfer &  
Trust Company
59 Maiden Lane 
Plaza Level 
New York, NY 10038 
(877) 777-0800, select option 1

www.amstock.com

Investor Relations e-mail:  
(Shareholder Inquiries) 
info@amstock.com

The Transfer Agent is responsible  
for handling shareholder questions 
regarding lost certificates, address 
changes and changes of ownership 
or name in which shares are held.

General Counsel

Goodwin Procter LLP 
Exchange Place
53 State Street
Boston, MA 02109

Independent Accountants

Ernst & Young, LLP
200 Clarendon Street
Boston, MA 02116

The Annual Meeting of  
Stockholders will be held on 
Thursday, September 9, 2010,  
at 10:00 AM at Repligen’s  
corporate offices:

41 Seyon Street
Building #1, Suite 100
Waltham, MA 02453

Market for Repligen  
Corporation Stock
NASDAQ Global Market
Common Stock: RGEN

Investor Information

Copies of our annual reports on 
Form 10-K, proxy statements, 
 quarterly reports on Form 10-Q  
and current reports on Form 8-K  
are available to stockholders upon 
request without charge. Please visit 
our website at www.repligen.com  
or send requests to:

Repligen Corporation 
41 Seyon Street 
Building #1, Suite 100 
Waltham, MA 02453

ATTN: Investor Relations 
Phone: (781) 250-0111 
Fax: (781) 250-0115

investors@repligen.com

Disclaimer 

This annual report contains “forward-looking statements” within the meaning of the federal securities laws. See discussion under “Management’s Discussion and Analysis of Financial 
Condition and Results of Operations” in this report for matters to be considered in this regard.

Annual Report Design by Curran & Connors, Inc. / www.curran-connors.com

41 Seyon Street
Building #1, Suite 100
Waltham, MA 02453
phone 781.250.0111
fax 781.250.0115
info@repligen.com

www.repligen.com