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Silence Therapeutics plc

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FY2022 Annual Report · Silence Therapeutics plc
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Silence Therapeutics Annual Report 2022

SILENCE THERAPEUTICS PLC 

Contents 
1 

Strategic report 

2 

Governance 

Board of Directors 

Corporate Governance Report 

Audit and Risk Committee Report 

Remuneration Committee Report 

3 

Financial Statements 

Consolidated Income Statement 

Consolidated Statement of Comprehensive Income 

Consolidated Balance Sheet 

Consolidated Statement of Changes in Equity 

Consolidated Statement of Cash Flows 

Notes to the Consolidated Financial Statements 

Company Balance Sheet 

Company Statement of Changes in Equity 

Notes to the Company Financial Statements 

Company Information and Advisers 

2 

22 

29 

35 

37 

55 

58 

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SILENCE THERAPEUTICS PLC 

Strategic Report 
Business Overview  

Silence Therapeutics plc 

is a biotechnology company focussed on 
discovering  and  developing  novel  molecules  incorporating  short  interfering  ribonucleic  acid,  or  siRNA,  to  inhibit  the 
expression of specific updated genes thought to play a role in the pathology of diseases with significant unmet medical 

specifically  binding  to  and  degrading  messenger  RNA,  or  mRNA,  molecules  that  encode  specific  targeted  disease-
associated proteins in a cell. By degrading the message that encodes the disease-associated protein, the production of 
that protein is reduced and its level of activity is lowered. In the field of RNAi therapeutics, this  reduction of disease-
Our proprietary mRNAi GOLD  (GalNAc 
Oligonucleotide  Discovery)  platform  consists  of  precision-engineered  medicines  designed  to  accurately  target  and 
disease-associated genes in the liver. Using our mRNAi GOLD  platform, we have generated siRNA 
product candidates both for our internal development pipeline as well as for out-licensed programmes with third-party 
collaborators.  Our  wholly  owned  pipeline  is  currently  focused  in  three  therapeutic  areas  of  high  unmet  need: 
cardiovascular disease, haematology and rare diseases.  

SLN360,  an  siRNA  targeting  the  LPA  gene,  is  our  wholly  owned  product  candidate  currently  in  phase  2  clinical 
development  (ALPACAR-360  trial),  to  reduce  high  levels  of  lipoprotein(a),  or  Lp(a),  a  genetically  determined 

from the single-ascending dose portion of the APOLLO phase 1 programme evaluating SLN360 in 32 healthy adults 
with high 
600 mg) had up to 96% and 98% median reduction in Lp(a) levels, respectively, and median reductions of up to 71% 
and 81% from baseline persisted at 150 days. Those receiving a placebo saw no change in Lp(a) levels. Further analysis 
showed median time-averaged Lp(a) reductions over 150 days exceeded 80% in the SLN360 300 mg and 600 mg dose 
groups. At day 365, some participants still exhibited substantial knockdown of Lp(a) to approximately 50% of baseline. 
SLN360  was  well  tolerated  with  no  serious  safety  concerns  reported.  The  multiple-ascending  dose  portion  of  the 
APOLLO programme in subjects with high Lp(a) and stable ASCVD is ongoing and expected to readout in the fourth 
quarter of 2023. In January 2023, we started dosing in the ALPACAR-360 phase 2 trial evaluating subjects with high 
tic cardiovascular disease, or ASCVD, events and we expect to complete 
enrolment by the end of 2023. We are engaged in global partnership discussions for this programme to ensure we are 
well positioned to scale up SLN360 development and future commercialization.   

SLN124,  an  siRNA  targeting  the  TMPRSS6  gene,  is  our  wholly  owned  product  candidate  that  has  shown  the 
potential to address a range of haematological conditions by modulating endogenous hepcidin, a peptide hormone that 
is the master regulator of systemic iron balance. SLN124 is being evaluated in the SANRECO phase 1/2 trial in patients 
with  polcythaemia vera,  or  PV, and the GEMINI II  phase  1 trial  in patients  with  non-transfusion dependent, or NTD, 
thalassemia. SLN124 demonstrated proof of mechanism in the GEMINI phase 1 trial in healthy volunteers completed in 
May  2021,  representing  the  first  clinical  data  from  our  mRNAi  GOLD   platform.  SLN124  has  FDA  Fast  Track  and 
orphan drug designations for PV as well as orphan drug and rare paediatric disease designations for beta-thalassaemia. 
The  European  Medical  Agency  has  also  granted  SLN124  orphan  drug  designation  and  rare  paediatric  disease 
designation for beta-thalassaemia.  

The  potential  of  our  mRNAi  GOLD   platform  has  been  validated  through  ongoing  research  and  development 
collaborations  with  leading  pharmaceutical  companies,  such  as  AstraZeneca,  Mallinckrodt  and  Hansoh.  These 
collaborations collectively represent up to 16 pipeline programmes and approximately $7.5 billion in potential milestones 
plus royalties.  

We  believe  the  potential  for  our  mRNAi  GOLD   platform  to  address  disease-associated  genes  in  the  liver  is 
substantial. Only around one percent of the approximately 14,000 liver expressed genes have been targeted by publicly 
known siRNAs. Once in the clinic, early-stage GalNAC-conjugated RNAi programmes have shown a greater likelihood 
of advancement from the current phase of development compared to the pharma industry average, according to a 2020 
industry  analysis  based  on  phase  transition  success  rates.  We  aim  to  maximize  our  mRNAi  GOLD   platform  by 
advancing both our proprietary and partnered pipelines. 

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Background on siRNA Molecules and RNA Interference 

Messenger RNA (mRNA) plays an essential role in the process used by cells to translate genetic information from 
DNA to create proteins. Transcription from DNA in the cell nucleus generates different types of RNA, including mRNA, 
which carries in the sequence of its nucleotides the genetic information which serves as molecular blueprints required 
for  translation,  or  protein  synthesis,  outside  of  the  nucleus  where  proteins  are  made.  In  some  cases,  cells  produce 
mRNA erroneously, resulting in synthesis of too much of a particular protein or a mutated protein variant, which can 
lead to disease. Our siRNAs are designed to bind to undesirable mRNA, whereupon a natural process known as RNA 
interference, or RNAi, is triggered, resulting in catalytic degradation of the mRNA and reduced production and activity 
of the disease-associated protein.  

RNAi is a naturally occurring biological pathway within cells for sequence-specific silencing and regulation of gene 
expression. RNAi was discovered by  Andrew Fire and Craig Mello,  and they were awarded the 2006 Nobel Prize in 
Physiology or Medicine for the discovery. RNAi therapeutics represent a novel advance in drug development that has 
the potential to transform the care of patients with genetic and other diseases. Historically, the pharmaceutical industry 
had developed only small molecules or recombinant proteins to inhibit the activity of disease-associated proteins. While 
this  approach is  effective  for  many  diseases,  a  number  of proteins  cannot  be  inhibited  by  either  small  molecules  or 
recombinant proteins. Some proteins lack the binding pockets small molecules require for interaction. Other proteins 
are solely intracellular and are therefore inaccessible to recombinant protein-based therapeutics, which are limited to 
cell surface and extracellular proteins. The unique advantage of RNAi is that, instead of targeting proteins, RNAi silences 
the expression of genes themselves via the targeted destruction of the mRNAs made from the gene. Rather than seeking 
to inhibit a protein directly, the RNAi approach works upstream to prevent its creation in the first place. 

Once inside a cell, siRNA molecules are recognised by the endogenous RNAi cellular machinery, which removes 
one of the strands, referred to as a passenger strand, of the siRNA construct thereby allowing the other strand, referred 
to as a guide strand, to find its target mRNA and bind to it through Watson-Crick base pairing. This site-specific binding 
triggers the biological process of RNAi interference, by which natural cellular machinery degrades target mRNA bound 
by the guide strand and thereby prevents it from being translated into functional proteins.  

Our  medicines  are  designed  to  harness  this  natural  pathway  to  develop  a  new  generation  of  therapeutics  by 
designing tailored siRNA sequences that are able to bind through Watson-Crick base pairing to mRNAs that code for 
specific  disease-associated  genes,  or  genes  that  regulate  them.  Our  siRNA  molecules  are  administered  by 
subcutaneous injection. Once administered, our siRNA molecules are taken up specifically by target liver cells or cleared 
from the body within hours. A single siRNA molecule, once in the liver and incorporated into the RNAi cellular machinery, 
can degrade large numbers 
catalytic activity of the RNAi pathway eventually fades with gradual degradation of the guide strands, RNAi-mediated 
protein reduction is not permanent. In our preclinical studies, we have observed a durable, dose-dependent silencing 
effect with our product candidates, with the highest dose resulting in reductions of between 50% and 85% or more of 
the target protein level over the course of several weeks to months following subcutaneous injection. As a result of the 
phase 1 clinical data we have generated in both our SLN360 and SLN124 programmes, we believe that these observed 
results suggest that our product candidates could lead to similar results in humans. The graphic below shows the steps 
involved in the pairing of our siRNA molecules with the bases contained in the mRNA sequence for a particular target 
gene. 

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We believe that siRNA molecules can, in theory, be engineered to bind specifically to and silence almost any gene 
in the human genome to which siRNA can be delivered. This potentially broad application of siRNA therapeutics could 
allow them to become a new major class of drugs. We are currently able to deliver siRNA molecules to liver cells using 
N-acetylgalactosamine, or GalNAc, for receptor-mediated targeting. GalNAc is an amino-modified monosaccharide that 
binds to asialoglycoprotein receptors, or ASGPRs, with high affinity and specificity. When GalNAc-conjugated siRNA 
molecules reach the surface of liver cells, they are internalised in those cells, with those not internalised being excreted. 
Once internalised
pathway. This GalNAc-siRNA drug modality is intended to enable precision medicine through the accuracy of Watson-
Crick base pairing of the siRNA to its target gene mRNA, coupled with the specificity of GalNAc-mediated delivery to 
the target gene-containing liver cell. 

Our mRNAi GOLD  platform uses a novel structure of double-stranded RNA with chemical modifications designed 
to improve the stability and efficacy of our siRNA molecules as well as to enhance delivery to targeted liver cells. We 
incorporate proprietary chemical modifications to enhance drug properties of our siRNA molecules, such as potency, 
stability  and tissue  distribution.  We believe  this  approach results  in  a  powerful  modular  technology  that  will  be  well-
suited  to  tackle  life-changing  diseases.  Particular  siRNA  molecules  are  designed  to  reduce  the  levels  of  a  disease-
associated protein directly, such as in the case of SLN360. In preclinical studies and our phase 1 single-ascending dose 
study, SLN360 was shown to directly reduce Lp(a) expression. Alternatively, in cases in which a disease-associated 
protein is normally subject to inhibition by a regulatory protein, siRNA molecules are designed to increase the levels of 
the disease-associated protein by silencing the inhibitory protein, thereby relieving inhibition and indirectly increasing 
levels of the protein normally subject to inhibition. In preclinical studies and in a phase 1 study in healthy volunteers, 
SLN124 was shown to indirectly up-regulate hepcidin levels by reducing the expression of a specific gene, TMPRSS6, 
which normally 
anaemia conditions 
in which hepcidin expression is typically low. Using these techniques, we believe we can design siRNA molecules to 
decrease high protein levels, and in some cases, to increase low protein levels, depending on the particular disease 
genes being targeted. 

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Our mRNAi GOLD  Platform 

Our mRNAi GOLD  platform comprises elements of our GalNAc-siRNA toolbox, our liver cell targeting technology 

and our target selection and screening process. 

GalNAc-siRNA Toolbox. Our mRNAi GOLD  platform is a toolbox comprising several different elements that can 
be incorporated into our double-stranded siRNA structure, known as blunt-ended 19-mers, either singly or in different 
combinations depending on individual siRNA sequences. The toolbox elements include:  

sugar modifications of one or more select individual nucleotides; 

stabilizing modifications of one or more internucleoside linkages in the sense and antisense strands; 

stabilizing modifications at one or more of the ends of the siRNA molecules;  

  a  five-

silencing complex, or RISC; and  

-induced 

  a versatile linker chemistry for GalNAc ligand conjugation in various numbers and configurations.  

When applying these elements of our toolbox, we also aim to reduce the overall content of the sugar modifications 

and the number of undefined stereogenic centres in the siRNA molecule. 

Liver Cell Targeting Technology. Blood flow and fenestra, or small openings in the endothelium, result in a large 
amount of the injected dose of a conjugated siRNA passing through the liver and reaching the main cell type of the liver 
known  as a hepatocyte. Hepatocytes are cuboidal epithelial cells that  line the liver sinusoids. Individual hepatocytes 
have approximately 0.5 to 1.0 million cell surface ASGPRs. GalNAc binds to ASGPRs with high affinity so that when 
GalNAc-conjugated siRNA reach the hepatocytes, they are internalised into the cells where siRNA can bind and, as a 

thereby  silencing  the  respective  gene. Only  a  small  fraction  of  the  initial  dose  reaches  the  hepatocyte  and  the  right 
compartment of the cell, but once the siRNA is there, it can stay active and intact for several months, allowing a small 
number of internalized siRNA molecules to exert a potent effect on the target mRNA. We apply the toolbox elements in 
the lead optimization phase to identify candidates that we believe will be potent with a long duration of action and have 
a favourable safety profile. 

Target  Selection  and  Screening  Process.  We  are  able  to  source  potential  product  candidates  through  a 
proprietary target selection process. The selection of new targets involves a careful analysis of the biology underlying 
an  indication,  disease  epidemiology  and  addressable  population,  the current  standard of  care  and resulting medical 
need, the commercial landscape and the envisaged clinical path. 

Our  screening  process  relies  on  a  proprietary  in  silico  algorithm  that  seeks  to  predict  the  most  efficacious  and 
specific siRNAs for any given target. This bioinformatics function is designed to continuously improve in silico predictions 
for finding potentially potent and safe siRNA sequences. The highest scoring drug candidates subsequently undergo a 
multi-step  evaluation  process  involving  several  rounds  of  in  vitro  screening  in  cell  lines  and  primary  hepatocytes  to 
identify the most potent molecules. Top candidates identified in vitro are then tested for safety and potential efficacy in 
animal  models.  At  this  point  in  the  process,  additional  modification  patterns  and  new  chemistries  are  introduced  for 
improvement of activity and duration of action while maintaining the desired safety profile. To be selected as a drug 
candidate  for  clinical  trials,  it  further  needs  to  be  shown  that  a  molecule  is  well  tolerated,  elicits  no  serious  adverse 
effects, and achieves strong and long-lasting knockdown of the targeted gene in a study with non-human primates. 

Translational  Genomics.  Our  translational  genomics  team  comprises  machine  learning  experts,  statistical 
geneticists,  bioinformaticians  and  software  engineers.  The  team  uses  state-of-the-art  methods  to  analyse  human 
genetic data to identify, characterise and prioritise new disease-causing gene targets, and develops machine learning 
models to enable us to continuously fine tune the siRNA design algorithm. By powering the analysis with the flexibility 
of cloud computing we are able to scale up our computational work as we grow. 

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Our Pipeline

Our  pipeline  is  centred around  our  liver-targeting  mRNAi  GOLD

platform  and  consists  of  a  diversified  set  of 

therapeutic areas, including haematology, cardiovascular disease and rare diseases. 

*Silence retains exclusive rights to this programme outside of the China region, which includes Hong Kong, Macau and 
Taiwan.

Our siRNA Product Candidates

SLN360

Overview

SLN360 is an siRNA molecule designed for the treatment of cardiovascular disease associated with elevated Lp(a), 
a lipoprotein in the blood. Available human data validate Lp(a) as an independent risk factor increasing the chances of 
developing  premature  cardiovascular  diseases,  including  coronary  heart  disease  and  unstable  angina,  as  well  as 
myocardial infarction and ischaemic stroke. SLN360 has the potential to reduce these diseases by specifically binding 
to and inducing RNAi-mediated degradation of the mRNAs made from LPA, the gene that encodes apolipoprotein(a), a 
product candidate 

for several indications for which Lp(a) has been shown to be a causal, independent risk factor. 

We believe SLN360 could be beneficial in addressing increased cardiovascular risk associated with raised levels of 

Lp(a) greater than 50mg/
Lp(a)  is  thought  to  be  higher  in  people  with  established  cardiovascular  disease  and  calcific  aortic  valvular  stenosis. 
Additionally, elevated Lp(a) concentrations are associated with an increased risk of myocardial infarction and ischaemic 
stroke, particularly in stroke patients 55 years of age and younger. There is a genetic link between plasma Lp(a) level 
and  cardiovascular  risk.  Mutations  that  genetically  cause  elevated  Lp(a)  levels  have  been  linked  with  increases  in 
myocardial infarction, ischaemic stroke, carotid stenosis, peripheral arterial disease (including femoral artery stenosis), 
abdominal aortic aneurysm, obstructed coronary vessels (i.e. coronary atherosclerotic burden), earlier onset of coronary 
artery disease, cardiovascular and all-cause mortality, increased risk of heart failure and reduced longevity. Importantly, 
these  causal  relationships  are  independent  of  concentrations  of  other  lipids  and  lipoproteins,  including  low-density 
lipoprotein, or LDL, and conventional cardiovascular disease risk factors. Conversely, a genetically determined decrease 
in Lp(a) has been associated with a 29% lower risk of coronary artery disease, 31% lower risk of peripheral vascular 
disease, 17% lower risk of heart failure, 13% lower risk of stroke and a 37% lower risk of aortic stenosis.

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SILENCE THERAPEUTICS PLC 

SLN360  is  administered  by  subcutaneous  injection  and  was  observed  to  have  a  long  duration  of  action  in  the 
APOLLO trial, potentially allowing for infrequent dosing, such as every three months or less frequently. In April 2022, 
results from the single-ascending dose portion of the APOLLO programme 
nmol/L  were  simultaneously presented in  a  late-breaking presentation at  the American  College  of Cardiology (ACC) 
Annual  Meeting  and  published  in  The  Journal  of  the  American  Medical  Association, or  JAMA.  In  January  2023,  we 
started dosing in the ALPACAR-
ASCVD events and we expect to complete enrolment in the fourth quarter of 2023. 

Disadvantages of existing treatment options 

Lp(a) is not susceptible to lifestyle changes and there are no currently available pharmacological treatments 
that cause an appreciable reduction in Lp(a). The only existing treatment to reduce Lp(a) is apheresis, which involves 
the removal of blood plasma from the body by the withdrawal of blood, its separation into plasma and cells, and the 
reintroduction of the cells, used especially to remove antibodies in treating autoimmune diseases. This process can take 
between two and four hours and is performed every one to two weeks. Consequently, it is invasive and burdensome for 
patients,  and it is  only available at limited  centres  at  a high  cost. Apheresis is primarily used in  Europe and it is not 
incorporated in the treatment guidelines in the United States.   

There  are  currently  no  approved  lipid-lowering  agents  specific  to  Lp(a).  Several  non-specific  agents,  largely 
targeting LDL cholesterol, have been observed to have only marginal or modest Lp(a) reductions, including ezetimibe 
(7%),  niacin  therapy  (23%),  cholesteryl  ester  transfer  protein,  or  CETP,  inhibitors  (25-60%),  and  antisense 
oligonucleotide-mediated inhibition of apo(b) by mipomersen (26%). Additionally, two monoclonal antibodies that inhibit 
proprotein  convertase  subtilisin/kexin  type  9,  or  PCSK9,  have  been  observed  to  reduce  Lp(a)  levels  by  20%-30%. 
However, randomisation studies have suggested that to produce a clinically significant reduction in cardiovascular risk, 
a  larger  reduction  in  Lp(a)  may  be  required,  something  that  we  believe  may  be  achieved  by  targeted  RNA-based 
approaches such as ours.   

Preclinical Data 

In a proof of mechanism study in cynomolgus monkeys, non-human primates also known as long-tailed macaques, 
administration of SLN360 lowered blood serum Lp(a) levels in a sustained manner. The chart below shows changes 
from baseline, or BL, levels with each data plot shown as an arithmetic mean plus or minus one standard deviation, or 
SD. As shown in the chart below, over nine weeks following administration of either a single dose of SLN360 (3 mg/kg 
or 9 mg/kg) on day 0 or three doses (of 3 mg/kg each) on days 0, 7 and 14, the largest dose resulted in a 95% reduction 
in Lp(a) levels. Individual animals observed in the study had their serum Lp(a) normalised to their own baseline levels, 
which are expressed as a nominal value of 100 in the chart below.  

SLN360-Induced Reduction in Serum Lp(a) in Cynomolgus Monkeys 

SLN360 has undergone an extensive nonclinical safety and pharmacokinetic evaluation, including rat biodistribution, 
repeat dose toxicity in two animal species (rat and the pharmacologically relevant cynomolgus monkey), including safety 
pharmacology investigations, and in vitro and in vivo genetic toxicity studies. SLN360 has displayed a typically short 
pharmacokinetic profile, where the compound is almost completely cleared from circulation in the blood after 24 hours. 

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SLN360  distribution  was largely  restricted to the  liver  and kidney, with levels  in  other  organs (including reproductive 
organs) at less than 1% of peak liver levels. SLN360 was shown to be non-genotoxic in the standard battery of genotoxic 
tests.  In  good  laboratory  practice  (GLP)  toxicology  studies,  SLN360  was  well  tolerated  up  to  the  maximum  dose 
administered.  All  findings in  both species were considered to  be  non-adverse.  In the cynomolgus monkey, the most 
relevant species, the No Observed Adverse Effect Level, or NOAEL, was 60 times the pharmacologically active dose, 
and  no  dose-related  changes  in  clinical  chemistry,  haematology,  circulatory  and  electrocardiography,  or  ECG, 
parameters, respiratory rate, neurobehaviour, plasma cytokines, complement activation or c-reactive protein levels were 
noted. 

Phase 1 Clinical Programme (APOLLO)  

The  APOLLO  phase  1  clinical  programme  is  a  global  randomised,  double-blind,  placebo  controlled,  single-
ascending  dose  and  multiple-ascending  dose  study  to  investigate  the  safety,  tolerability,  pharmacodynamic  and 
pharmacokinetic response  of SLN360 administered subcutaneously in up to 88  people total with high Lp(a) levels of 

In February 2022, we reported positive results from the single-ascending dose portion of the APOLLO phase 

1 programme 
APOLLO trial were simultaneously presented in a late-breaking presentation at the ACC Annual Meeting and 
published in JAMA. In the APOLLO trial, participants in the top two SLN360 single dose groups (300 mg and 600 mg) 
had up to 96% and 98% median reduction in Lp(a) levels, respectively, and median reductions of up to 71% and 81% 
from baseline persisted at 150 days. Those receiving a placebo saw no change in Lp(a) levels. Other efficacy 
measures included the effects of SLN360 on low-density lipoprotein cholesterol (LDL cholesterol) and apolipoprotein B 
(ApoB), both of which are associated with an increased risk of cardiovascular events. The highest doses of SLN360 
reduced LDL cholesterol and ApoB by about 25%. SLN360 was well tolerated with no serious safety concerns 
reported. In November 2022, we presented a further analysis from the APOLLO trial up to 365 days in a moderated 
-

esults from the 

averaged Lp(a) reductions over 150 days exceeded 80% in the SLN360 300 mg and 600 mg dose groups. At day 365, 
some participants still exhibited substantial knockdown of Lp(a) to approximately 50% of baseline. Additionally, 
extension data to day 365 showed no new drug related safety findings. The multiple-ascending dose portion of the 
APOLLO study in subjects with high Lp(a) and stable ASCVD is ongoing and expected to readout in the fourth quarter 
of 2023. 

Phase 2 Clinical Programme (ALPACAR-360)  

The  ALPACAR-360  phase  2  clinical  trial  is  a  randomised,  double-blind,  placebo-controlled  trial  enrolling 

randomly assigned to receive either two or three doses of SLN360 or placebo administered subcutaneously. The primary 
endpoint is time averaged change in Lp(a) from baseline. In January 2023, we announced that we started dosing patients 
in the ALPACAR-360 trial and we expect to complete enrolment in the fourth quarter of 2023. 

SLN124 

Overview 

SLN124  is  an  siRNA  molecule  designed  to  treat  ineffective  erythropoiesis,  or  the  production  of  red  blood  cells, 
associated  with  iron  overload  disorders  and  with  primary  or  secondary  dysregulation  of  hepcidin  synthesis.  These 
constitute  diseases  associated  with  pathologically  low  hepcidin  and  diseases  in  which  there  is  inadequate  hepcidin 
response for the degree of iron loading, such as beta-thalassaemia and polycythaemia vera (PV). Left untreated, iron 
overload disorders cause damage to the heart, liver, pituitary gland, adrenal gland, testes, pancreas, ovaries and kidney 
and endocrine organs. Beta-thalassaemia is often accompanied by the destruction of a large number of red blood cells, 
which causes the spleen to enlarge and work harder than normal, potentially worsening the anaemia. Beta-thalassaemia 
is a rare disease, with an overall prevalence of 1 per 100,000 persons, rising in certain regions (such as Mediterranean 
Europe, the Middle East and South East Asia) to 1 per 10,000 persons. Globally, there are over 60,000 new cases of 
beta-thalassaemia each year, of which there are approximately 15,000 cases in the United States and the five major 
markets  in  Europe.  PV  is  a  chronic  myeloproliferative neoplasm,  where  the  body  makes  too  many  blood  cells.  This 
increases the thickness of the blood and can lead to an increased risk of thrombosis (blood clots). The disease often 
presents later in life (60-65 years) and affects approximately 44 per 100,000 persons in Europe and the United States. 

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SLN124 has the potential to reduce systemic iron, prevent organ iron overload and normalize erythropoiesis. It does so 
by  specifically  binding  to  and  inducing  RNAi-mediated  degradation  of  mRNAs  made  from  the  gene  TMPRSS6,  a 
negative regulator of hepcidin, which is the main hormone controlling iron homeostasis.   

SLN124 is administered by subcutaneous injection and has demonstrated a long duration of action in the GEMINI 
healthy volunteer trial completed in May 2021. Data from the trial showed that SLN124 was effective in reducing plasma 
iron levels and had a long duration of action. In September 2022, we reported preliminary safety data from the single 
dose component of the GEMINI II phase 1 trial of SLN124 in patients with NTD thalassaemia. Data showed SLN124 
was well tolerated with no serious safety issues identified. The multiple dose component of the GEMINI II trial is ongoing 
and expected to readout in the fourth quarter of 2023. SLN124 is also being evaluated in the SANRECO phase 1/2 trial 
in polycythaemia vera (PV) patients.   

In 2019, the EMA granted SLN124 orphan drug designation for the treatment of beta-thalassaemia. In 2020, the 
FDA granted rare paediatric disease designation for the treatment of beta-thalassemia and orphan drug designations 
for the treatment of myelodysplastic syndrome (MDS) and adult beta-thalassaemia. In 2022, the FDA granted Fast Track 
and orphan drug designations for SLN124 in PV.   

Disadvantages of existing treatment options 

The cornerstone of treatment for iron loading anaemias, like beta-thalassaemia, is the regular transfusion of 
packed red blood cell, or RBC, units. Despite providing immediate symptomatic relief by boosting haemoglobin levels 
(therefore  reducing  anaemia),  RBC  transfusions  are  burdensome,  require  frequent  hospital  visits  (every  two  to  five 
weeks)  and carry  the  risk  of  further  iron  overload.  Iron  chelators  are  the  standard  of  care  for  the  prevention  of  iron 
overload and can be administered by intravenous or subcutaneous twice daily injections (deferoxamine) or taken orally 
once (deferasirox) to three times daily (deferiprone). While orally available chelators, particularly Deferasirox (Exjade) 
are currently prescribed due to their ease of administration, some patients still need to receive deferoxamine infusions. 
Regardless of administration profile, chelator use carries a known risk of severe side effects with several restrictions of 
use and black box warnings  regarding potential renal, ophthalmic, hepatic and gastrointestinal, or  GI, toxicity/failure, 
with common acute GI side effects including abdominal pain, diarrhoea, nausea and vomiting. The side effect profile as 
well as frequency of administration and perceived bad taste are reported as drivers of poor patient compliance with this 
existing treatment option.  

Luspatercept (Reblozyl) is approved for the treatment of adults with transfusion-dependent beta-thalassaemia, 
and  adults with  erythropoiesis-stimulating  agent  (ESA)  refractory  MDS with ringed  sideroblasts.  We  believe  that  the 
limited response rates observed in the MEDALIST and BELIEVE pivotal studies suggest that there remains a substantial 
unmet need among these patients. Lentiglobin (Zynteglo) is a gene therapy approved in the U.S. and Europe for the 
treatment of a subset of patients with transfusion-dependent beta-thalassaemia. We believe that outstanding questions 
surrounding the cost, safety and durability of gene therapies and their associated pre-conditioning regimens will limit 
their uptake, leaving a substantial unmet need for the treatment of beta-thalassaemia.  

The primary treatment goal in PV is to reduce the risk of thrombotic events by reducing haematocrit (the number of 
blood cells in a given volume) to within target levels. The mainstay of treatment is therapeutic phlebotomy to reduce the 
number of blood cells by regularly removing blood from the patient. Phlebotomy results in erratic, suboptimal control of 
haematocrit, and regular phlebotomies can be burdensome to the patient. Patients over 60, or those with prior thrombotic 
events  or  additional  cardiovascular  risk  factors  are  also  treated  with  chemotherapy  drugs  (cytoreductive  agents)  to 
suppress blood cell production. The majority of these patients are treated with hydroxyurea, which is poorly tolerated 
and carries the risk of potential long term side effects. Patients who are resistant or intolerant to hydroxyurea may be 
treated with the JAK2 inhibitor ruxolitinib (Jakafi), which carries the risk of thrombocytopenia (low platelet count). Finally, 
some patients are treated with synthetic hepcidin mimetic dosed weekly by subcutaneous injection in clinical trials. In 
contrast to  synthetic hepcidin mimetics, SLN124  elevates  endogenous hepcidin  produced and secreted by the  liver, 
avoiding high local concentrations of hepcidin at the injection site. We believe the sustained duration of action will allow 
SLN124 to be dosed monthly, or less frequently, bringing additional value to patients.  

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SILENCE THERAPEUTICS PLC

Preclinical Data 

Preclinical data in a PV transgenic mouse model

A proof-of-concept study was conducted with an inducible PV mouse model to determine if TMPRSS6 siRNA can 
raise  endogenous  hepcidin  levels  in  this  condition,  restrict  iron  from  erythropoiesis  and  thereby  attenuate  disease 
progression and severity.

The majority of PV patients have a JAK2 gene gain of function mutation, JAK2V617F. Since JAK-STAT signalling
is involved in the regulation of hepcidin in the liver, it was imperative to create a PV model that restricted the expression 
of mutant JAK2 allele to the bone marrow (BM). A pharmacodynamic study was conducted using a tamoxifen inducible 
(CreERT2) BM transplant mice model of PV with the human JAK2V617Fallele. Control mice lack the inducible CreERT2. 
The  model  recapitulates  human  disease  with  increased  red  blood  cells,  haematocrit and  haemoglobin compared  to 
control animals. Importantly, our model has hepcidin levels in line with control animals, recapitulating what has been 
previously reported in PV patients.

               Inducible bone marrow transplant model of polycythaemia vera

A) Red blood cells (RBC), (B) haematocrit, (C) haemoglobin and (D) serum hepcidin in control (n=13) and PV mice 

(n=20). Data are presented as mean +/-

Treatment of the PV mice with TMPRSS6 siRNA resulted in an approximately 95% reduction in TMPRSS6 mRNA 
levels which also resulted in a 3.1-fold increase in hepcidin levels in comparison to siCTR. The increased hepcidin levels 
caused a 25% and 32% reduction in haematocrit and haemoglobin, respectively, in comparison to siCTR

                TMPRSS6 siRNA increases hepcidin and decreases the erythron

A) Liver Tmprss6 mRNA, (B) serum hepcidin, (C) haemoglobin and (D) haematocrit of PV mice treated by 
subcutaneous injections of PBS (n=12), non-targeting control siRNA, siCTR (n=11) or Tmprss6 siRNA, siTMP (n=13). 

Data are presented as mean +/-

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SILENCE THERAPEUTICS PLC

Mice treated with TMPRSS6 siRNA had decreased mean cell volume compared to siCTR siRNA treated mice, which 
is indicative of iron restricted erythropoiesis. TMPRSS6 siRNA significantly decreased serum iron levels, however it did 
not have an effect on liver iron levels, in comparison to siCTR treated mice.

Figure15                TMPRSS6 siRNA treatment decreases serum iron

(A) Serum iron, (B) Mean cell volume and (C) liver iron in PV mice treated with subcutaneous injections of PBS 
(n=12), non-targeting control (siCTR) siRNA (n=11) and Tmprss6 siRNA, siTMP (n=13). Data are presented as mean 

+/-

Preclinical data in a beta thalassaemia rodent disease model

In a beta-thalassaemia rodent disease model, SLN124 reduced expression of its target gene, TMPRSS6, in the liver 
after 35 days, while also increasing serum hepcidin levels and lowering transferrin saturation. On days 1 and 15 of the 
-globin genes, also known as Hbbth3/+, were treated with either 
3 mg/kg of SLN124 subcutaneously as monotherapy or with the same dose of SLN124 in combination with 1.25 ng/mL 
of  deferiprone supplied  in  drinking  water. One cohort of mice  was  treated  with  deferiprone  alone. The control  group 
consisted of mice having TMPRSS6 siRNA without a ligand. 

TMPRSS6 mRNA levels were assessed by quantitative Reverse Transcription Polymerase Chain Reaction, or qRT-
PCR,  a  common  laboratory  technique,  and  were  normalised  to  the  endogenous  reference  actin  relative  to  their 
expression levels in control treated animals. These TMPRSS6 mRNA levels are shown in the left panel of the figure 
below. Serum hepcidin levels were determined using an ELISA assay and are shown in the middle panel of the figure 
below. Transferrin saturation, a clinical biomarker for serum iron levels, was calculated based on total serum iron and 
total iron binding capacity, and the observations from the study are shown in the right panel of the figure below. 

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SILENCE THERAPEUTICS PLC

In the figure below, we show the results  from  administration  on individual animals  as well as  the  mean for  each 
group plus or minus one standard deviation. The figures show that administration of SLN124, either as monotherapy or 
in combination with deferiprone, reduced TMPRSS6 mRNA levels as compared to the control group or treatment with 
deferiprone alone. The two mouse groups receiving SLN124 also experienced comparatively higher hepcidin levels and 
lower transferrin saturation levels than the control group or the deferiprone only group (the deferiprone only control data 
being non-statistically significant
be confirmed in human clinical trials.

SLN124 reduced live

-thalassaemic mice compared to deferiprone

-thalassaemic mice compared to deferiprone

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SILENCE THERAPEUTICS PLC

-thalassaemic mice compared to deferiprone

In  our  preclinical  studies  of  beta-thalassaemic mice,  we  also  observed  that  administration  of  SLN124  improved 
anaemia, which led to reduced extramedullary erythropoiesis, evident by the reduction in spleen weight shown in the 
left panel of the figure below. In these studies, mice were  dosed twice over two weeks, following which their spleen 
weight and haemoglobin levels were measured over five weeks. As shown in the right panel of the figure below, we 
observed a median increase of 2.5 g/dL in haemoglobin levels, or 30% more than the control group, in the mice receiving 
SLN124 in this study. Increases of at least 1.5 g/dL are generally considered to be clinically relevant responses, based 
on 2018 International Working Group standardized response criteria for showing haematologic improvement in patients 
with MDS. 

SLN124 reduced spleen weight and improved ana

-thalassaemic mice

Data based on collaboration with Dr. J. Vadolas, Australia, Monash Medical Centre/Melbourne. 

SLN124  has  undergone  an  extensive  nonclinical  safety  and  pharmacokinetic  evaluation  including  mouse 
biodistribution, single and repeat dose toxicity in two relevant animal species (mouse and cynomolgus monkey) including 
safety pharmacology investigations, and in vitro genetic toxicity studies. Drug-drug interaction studies have also been 
carried  out  as  the  initial  clinical  trial  will  also  be  performed  in  a  patient  population  that  may  be  using  concomitant 
medications. The toxicological data obtained so far are regarded as adequate to support single and repeated intermittent 
monthly treatment in humans.

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SILENCE THERAPEUTICS PLC 

In these nonclinical evaluations, SLN124 was highly absorbed within hours, while its pharmacodynamic effects were 
sustained over weeks. SLN124 was distributed to the liver and kidney with little or no detectable tissue concentrations 
in other tissues, including brain and reproductive organs. The nonclinical safety has been assessed in a series of GLP 
pharmacology studies. In these studies, ECG, blood pressure and respiration were assessed in cynomolgus monkeys 
without any test-article related observations. Evaluation of SLN124 in weekly repeat dose GLP studies in mouse and 
non-human  primates has not revealed any  unexpected findings. The NOAEL was more than  25  times the  predicted 
efficacious pharmacological dose in both the mouse  and monkey species. In vitro experiments in mammalian assay 
systems confirmed the lack of genotoxicity. In drug-drug interaction studies, SLN124 was not a direct or time-dependent 
inhibitor of analysed cytochrome enzymes and was neither an inhibitor nor a substrate of analysed transporters under 
the conditions examined.  

Healthy Volunteer Trial (GEMINI)  

The GEMINI phase 1 trial was a randomised, double-blind, placebo controlled, single-ascending dose study to 
investigate  the  safety,  tolerability,  PK  and  PD  response  of  SLN124  (1.0,  3.0  and  4.5  mg/kg  doses)  administered 
subcutaneously in 24 healthy volunteers. In May 2021, we reported positive data from the GEMINI Trial, which was the 
first clinical data from our mRNAi GOLD  platform. In December 2021, we presented further clinical data from the study 
at the American Society of Haematology (ASH) Annual Meeting. Key outcomes included: 

  All 3 dose levels were well tolerated with no serious or severe treatment emergent adverse events, or TEAEs, 

leading to withdrawal.  

  Average hepcidin, a key endogenous regulator of iron balance and distribution, increased up to ~4-fold after a 

single dose with effect sustained for at least 2 months. 

  Serum iron reduced by ~50% after a single dose with effect sustained for at least 2 months. 
  SLN124 was rapidly distributed (median tmax was 4.0 or 5.0 hours) and largely eliminated from plasma within 
24 hours post-dose in all dosing groups. SLN124 plasma concentrations increased in a greater than dose-linear 
fashion between dosing groups. 

  All  SLN124  doses  induced  marked  reductions  in  transferrin  saturation,  or  TSAT;  absolute  levels  of  TSAT 
achieved (10 16%) are below the level (< 20%) where iron availability to tissue is restricted and at or below that 
(< 16%) required to support normal erythropoiesis in health. 

Thalassaemia Phase 1 Programme (GEMINI II)  

The GEMINI II phase 1 programme is a global, randomized, single-blind, placebo controlled, single-ascending 

and multiple-ascending dose studies to investigate the safety, tolerability, PK and PD response of SLN124 in 
approximately 24 adults with NTD thalassaemia. In September 2022, we reported preliminary safety results from the 
single-ascending dose portion of the trial showing SLN124 was well tolerated with no serious adverse events, or AEs, 
no severe TEAEs that were SLN124 related and no TEAEs leading to withdrawal identified. Effects on hepcidin, 
serum iron, transferrin saturation and haemoglobin are being evaluated in the ongoing multiple-dose arm expected to 
readout in the fourth quarter of 2023.   

Polycythaemia Vera Phase 1/2 Programme (SANRECO) 

The SANRECO phase 1/2 PV programme is a two-part clinical trial which includes a phase 1 open-label, dose 
finding trial followed by a phase 2 randomised, double-blind, placebo-controlled parallel arm study of SLN124 in PV 
patients. The study is expected to enrol approximately 65 participants total. The primary endpoint for the phase 1 
portion of the trial is safety/tolerability and the assessment of the number of phlebotomies at different intervals. The 
phase 2 portion of the trial will evaluate the number of patients who are phlebotomy free after treatment. In January 
2023, we announced that sites are open for enrolment.  

Collaborations 

In July 2019, we announced a strategic collaboration  with Mallinckrodt to develop and commercialize RNAi drug 
targets  designed  to  silence  the  complement  cascade  in  complement-mediated  disorders.  Under  the  agreement,  we 
granted Mallinckrodt an exclusive worldwide license to our C3 targeting programme, SLN501, with options to license 
additional  complement-mediated  disease  targets  from  us,  with  Mallinckrodt  exercising  the  option  for  two  additional 
targets in July 2020. We are responsible for preclinical activities, and for conducting each development programme until 

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the end of phase 1 clinical trials, after which Mallinckrodt will assume clinical development and responsibility for global 
commercialisation. In connection with the execution of the agreement, Mallinckrodt made an upfront cash payment to 
us of $20 million (£16.4 million) and purchased $5 million of our ordinary shares. We are eligible to receive up to $10 
million in potential research milestone payments, in addition to funding for the phase 1 clinical development of SLN501 
including GMP manufacturing. We will fund all other preclinical activities. We received a $2 million (equivalent to £1.6 
million based on the exchange rate at the payment date) research milestone payment in October 2019 upon the initiation 
of  work  on  the  first  C3  target.  In  September  2020,  we  received  another  $2  million  (£1.4  million)  research  milestone 
payment following the initiation of work on a second complement target. In February 2021, we initiated work on the third 
complement target which triggered another $2 million (£1.5 million) research milestone payment. In April 2021, we also 
received $2 million (£1.5 million) for the second research milestone related to the SLN501 C3 targeting programme and 
triggered another $3 million milestone payment following the submission of the SLN501 clinical trial application in March 
2022. The collaboration provides for potential additional development and regulatory milestone payments in aggregate 
of up to $100 million for the initial C3 target and up to $140 million for each of the two optioned complement-mediated 
disease targets, with such  milestones relating to  the  initiation of specified clinical trials in specified  jurisdictions,  and 
upon  the  receipt  of  regulatory  approvals  by  specified  authorities,  in  each  case  for  multiple  indications.  We  are  also 
eligible to receive potential commercial milestone payments of up to $562.5 million upon the achievement of specified 
levels of annual net sales of licensed products for each programme. We are also eligible to receive tiered, low double-
digit to high-teen percentage royalties on net sales for licensed products for each programme. 

In March 2020, we announced a strategic collaboration with AstraZeneca to discover, develop and  commercialise 
siRNA therapeutics for the treatment of cardiovascular, renal, metabolic and respiratory diseases. AstraZeneca made 
an upfront cash payment to us of $20 million (equivalent to £17.1 million based on the exchange rate at the payment 
date) in May 2020 and an additional cash payment of $40 million (equivalent to £30.8 million based on the exchange 
rate at the payment date) in May 2021. AstraZeneca also made an equity investment of $20 million in our company in 
March 2020. We anticipate initiating work on five targets within the first three years of the collaboration, with AstraZeneca 
having the option to extend the collaboration to a further five targets. AstraZeneca has agreed to pay us $10 million for 
each selected target at the point of candidate nomination. For each target selected under the collaboration, we will be 
eligible to receive up to $140 million in milestone payments upon the achievement of milestones relating to the initiation 
of  specified  clinical  trials,  the  acceptance  of  specified  regulatory  filings  and  the  first  commercial  sale  in  specified 
jurisdictions. For each target selected, we will also be eligible to receive up to $250 million in milestone payments as 
well as tiered royalties as a percentage of net sales ranging from the high single digits to the low double digits.  

On October 15, 2021, we announced a collaboration agreement with Hansoh, one of the leading biopharmaceutical 
companies in China, to develop siRNAs for three undisclosed targets leveraging Silence's proprietary mRNAi GOLD  
platform. Under the terms of the agreement, we retain exclusive rights to the first two targets in all territories except the 
China Region (Greater China, Hong Kong, Macau and Taiwan). Hansoh has the exclusive option to license rights to 
those two targets in the China Region following the completion of phase 1 studies. Silence will be responsible for all 
activities  up  to  option  exercise  and  will  retain  responsibility  for  development  outside  the  China  region  post  phase  1 
studies. Hansoh will also have the exclusive option to license global rights to a third target at the point of IND filing. 
Hansoh will be responsible for all development activities post option exercise for the third target. Hansoh made a $16 
million upfront payment to us in December 2021. We achieved our first $2 million research milestone payment  in the 
Hansoh collaboration in April 2022. We are eligible to receive up to $1.3 billion in additional development, regulatory 
and  commercial  milestones.  We  will  also  receive  royalties  tiered  from  low  double-digit  to  mid-teens  on  Hansoh  net 
product sales. In December 2022, we initiated work on the second target which we retain global rights to outside the 
China Region. 

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SILENCE THERAPEUTICS PLC 

SLN501: Complement Factor C3 Programme 

SLN501  is  our  siRNA  partnered  with  Mallinckrodt  that  targets  C3  and  is  in  development  for  complement-mediated 
diseases. In June 2022, we initiated a phase 1 trial in healthy volunteers. 

Overview of the complement system 

The complement system plays a pivotal role in both innate and adaptive immune systems. Complement proteins 
are  produced  primar
 complement 
system may be activated through three principal pathways, known as the classical, lectin and alternative pathways, each 
of which requires the C3 protein to enable three principal immune responses: opsonization, inflammation and formation 
of the membrane attack complex, or MAC. When C3 is activated, C3 fragments, such as C3b, tag cell surfaces in a 
process called opsonization, which marks the cells for removal from tissues or the bloodstream. Two other fragments, 
C3a  and  C5a,  are  released,  contributing  to  inflammation  in  the  surrounding  tissues.  Further  complement  activation 
causes MAC formation on cell surfaces, piercing holes and causing cells to lyse, or rupture. 

Under conditions of excessive or uncontrolled activation, the complement system is believed to play a key role in 
the incidence and progression of several autoimmune and inflammatory diseases. In these diseases, the complement 
system acts directly through tissue destruction by the MAC and indirectly by signalling other elements of the immune 
system to inappropriately target  otherwise healthy tissues. Because  the contribution of  complement  activation to the 
development and progression of these diseases is not fully understood, it has been difficult to develop therapeutics that 
ameliorate the conditions contributing to these diseases by targeting only one of the complement activation pathways. 

Competition 

The  life  sciences  industry  is  characterised  by  rapidly  advancing  technologies,  intense  competition  and  a  strong 
emphasis  on  proprietary  products.  We  face  potential  competition  from  many  different  sources,  including  major 
pharmaceutical, specialty pharmaceutical and biotechnology companies, academic institutions, governmental agencies 
and  public  and  private  research  institutions.  Many  of  our  competitors  may  have  greater  experience  in research  and 
development,  manufacturing,  managing  clinical  trials  and/or  regulatory  compliance  than  we  do,  and  may  be  better 
resourced financially. Any product candidates that we successfully develop and commercialise will compete with existing 
products and new products that may become available in the future. These competitors also compete with us in recruiting 
and retaining qualified scientific and management personnel and establishing clinical study sites and patient registration 
for clinical studies, as well as in acquiring technologies complementary to, or necessary for, our programmes.  

Companies that complete clinical trials, obtain required regulatory authority approvals and commence commercial 
sale  of  their  drugs  before  their  competitors  may  achieve  a  significant  competitive  advantage,  and  our  commercial 
opportunity  could  be  reduced  or  eliminated  if  competitors  develop  and  commercialise  products  that  are  safer,  more 
effective, have fewer or less severe side effects, are more convenient or are less expensive than any products that we 
may develop and commercialize. Because our products and many potential competing products are in various stages 
of preclinical and clinical development, and given the inherent unpredictability of drug development, it is difficult to predict 
which third parties may provide the most competition, and on what specific basis. 

In  addition  to  the  competition  we  face  from  competing  drugs  in  general,  we  also  face  competition  from  other 
companies working to develop novel drugs using technology that competes more directly with our own. We are aware 
of several other companies that are working to develop RNAi therapeutic products and other companies may develop 
alternative treatments for the diseases we have identified as being potentially treated with our siRNA molecules. To the 
extent those alternative treatments are more efficacious, less expensive, more convenient or produce fewer side effects, 
our market opportunity would be reduced. We anticipate that we will face intense and increasing competition as new 
products and therapies enter the market and advanced technologies become available. We expect any treatments that 
we  develop  and  commercialise  to  compete  on  the  basis  of,  among  other  things,  efficacy,  safety,  delivery,  patient 
friendliness, price and the availability of reimbursement from government and other third-party payors. 

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SILENCE THERAPEUTICS PLC 

Financial Review 

Revenue 

Revenue for the year ended 31 December 2022 was £17.5 million (2021: £12.4 million). The increase was primarily due 
to the advancement of targets in our Mallinckrodt and AstraZeneca collaborations which delivered £16.7 million in 2022 
(2021: £11.4 million).  

Research and Development Expenses  

Research and development expenses for the year ended 31 December 2022 were £35.6 million as compared to £30.8 
million for the year ended 31 December 2021. Contract development costs increased by £3.2 million from 2021 as a 
result of additional clinical studies and an increase in contract manufacturing activities for our proprietary programmes. 
Personnel  costs  also  increased  by  £1.2  million  from  2021  as  we  increased  our  capabilities  and  expertise  to  further 
advance our siRNA platform. 

Cost of sales consists of research and development expenditure that is directly related to work carried out on revenue 
generating contracts, which increased to £10.9 million for the year ended 31 December 2022 (2021: £7.5 million). The 
increase was largely due to the further advancement of our collaboration programmes. 

General and Administrative Expenses  

General and administrative expenses were £19.6 million for the year ended 31 December 2022 as compared to £20.0 
million  for the year ended  31 December 2021. While there was an increase in payroll costs  of £1.6  million, this was 
offset by a reduction in consulting and recruiting costs of £0.6 million as we continue to reduce reliance on consultants. 
The remainder of the decrease is due to finance, insurance, internal control, travel and legal costs as we continue to 
benefit from efficiencies gained and the monitoring of administrative costs.  

Finance and Other Income (Expense) 

Finance income represents bank interest and accretion from U.S. Treasury Bills. For December 31, 2022, this was £0.2 
million (2021: £10 thousand). The increase of  finance income in 2022 can mainly be attributed to purchases of U.S. 
Treasury Bills in 2022. 

Also  included in the Finance and  other Income total is  foreign exchange  gains  of £1.0  million  and £nil for  the  years 
ended December 31, 2022, and 2021, respectively. Net foreign exchange gains and losses result primarily from foreign 
currency (Euro and USD) denominated bank accounts.  

Finance expense for the year ended December 31, 2022, was £47 thousand, resulting from interest expense incurred 
in connection with lease liabilities, compared to £8 thousand for the prior year. 

Also included in the Finance and other expense total is foreign exchange losses of £nil and £44 thousand for the years 
ended December 31, 2022, and 2021, respectively. Net foreign exchange gains and losses result primarily from foreign 
currency (Euro and USD) denominated bank accounts.  

Taxation 

During 2022 and 2021, we have recognized U.K. research and development tax credits of £7.8 million and £6.9 million, 
respectively in respect of R&D expenditures incurred; the higher tax credit in current year due to an increase in R&D 
expenditure compared to previous year. This amount was offset by tax charges in our foreign tax expense. 

Liquidity, cash and cash equivalents 

As of December 31, 2022, we had cash, cash equivalents and U.S. Treasury Bills of £71.1 million ($86.0 million), which 
reflects the registered direct offering, or the Offering, of 5,950,000 ADSs, at a public offering price of $9.50 per ADS, in 
August 2022. Our aggregate gross proceeds from this offering were $56.5 million (approximately £46.4 million) before 
deducting  $4.1  million  (approximately  £3.3  million)  in  underwriting  discounts,  commissions  and  estimated  offering 
expenses. 

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SILENCE THERAPEUTICS PLC 

The Company is a development stage business and does not yet generate revenues or other operating cash inflows 
from commercial sales. The Company therefore has primary KPI of cash and short-term investments. 

Strategic  objective:  Availability  of  financial  resources  to  progress  the  development  of  research  and  development 
activities of the Company and its subsidiaries. 

Key Performance Indicator: Year-end cash and short-term investments: £71.1 million (2021: £73.5 million)  

Principal Risks 

We constantly monitor and assess the overall risk of doing business in the biopharmaceutical industry and the particular 
risks associated with our current activities and corporate profile.  Having carried out a review  of the level of risks the 
Company and its subsidiaries is taking in pursuit of its strategy, the board of directors 
is 
satisfied that the level of retained risk is appropriate and commensurate with the financial rewards that should result 
from the achievement of its strategy. The main risks have been identified as followed:  

  The approach we are taking to discover and develop drugs is novel and we may not be successful in our efforts 

to identify or discover potential drug product candidates to bring into clinical trials.  

If clinical trials of our product candidates fail to commence or, once commenced, fail to demonstrate safety and 
efficacy to the satisfaction of regulatory authorities, or do not otherwise produce positive results, we may incur 
additional costs or experience delays in completing, or ultimately be unable to complete, the development and 
commercialisation of our product candidates.  

  We  have  a  history  of  net  losses  and  we  anticipate  that  we  will  continue  to  incur  significant  losses  for  the 

foreseeable future.  

  We will need to raise additional capital, which may not be available on acceptable terms, or at all.  

  We face competition from other companies that are working to develop novel drugs and technology platforms 
using technologies similar to ours. If these companies compete with us for limited manufacturing supplies, or 
for  animals  critical  for  preclinical  testing,  or  otherwise  develop  drugs  more  rapidly  than  we  do  or  their 
technologies,  including  delivery  technologies,  are  more  effective,  our  ability  to  successfully  commercialise 
drugs may be adversely affected.  

  We rely on third parties to conduct some aspects of our manufacturing, research and development activities, 
and those third parties may not perform satisfactorily, including failing to meet deadlines for the completion of 
research or clinical testing.  

If we are unable to obtain or protect intellectual property rights related to our current or future product candidates, 
we may not be able to compete effectively in our markets.  

  We qualify as a foreign private issuer and, as a result, we will not be subject to U.S. proxy rules and will be 
subject to  Exchange  Act reporting obligations that, to some extent,  are more lenient and less frequent than 
those of a U.S. domestic public company.  

If equity research analysts do not publish research or reports, or publish unfavourable research or reports, about 
us, our business or our market, the price and trading volume of our ADSs could decline.  

adversely impact our ability to obtain regulatory approvals of our product candidates in the European Union, 
result in restrictions or imposition of taxes and duties for importing our product candidates into the European 

18 

 
 
 
 
 
 
 
SILENCE THERAPEUTICS PLC 

Union, and may require us to incur additional expenses in order to develop, manufacture and commercialize 
our product candidates in the European Union.  

  The Ukraine/Russia War could adversely affect our operations, including increases in the prices of the supplies 

used in our business, supply chain interruptions and increased cybersecurity risks.  

Inflation may adversely affect our operations, including increases in the prices of goods and services required 
for our operations.  

Corporate Social Responsibility 

medicines whilst driving positive change for the communities around us. As part of this we are committed to corporate 
social responsibility.  

Social, Community & Human Rights 

Our aim is to improve global health by bringing transformative treatments to adults and children in need, including for 
rare  diseases 
continued to progress: 

  SLN360:  Announced  positive  results  from  the  APOLLO  phase  1  single-ascending  dose  study  in  healthy 

volunteers with high Lp(a). 

  SLN124: Announced preliminary safety results from the single ascending dose portion of the GEMINI II phase 

1 study in thalassaemia patients. 

We are committed to creating inclusive policies and equal opportunities for our current generation, while encouraging 

Throughout 2022, we continued our UK policy initiatives with a successful podcast hosted by the Foundation for Science 
and Technology and a white paper stating the case for regulatory and clinical trial reform.  The white paper has been 
distributed to relevant MPs, policy makers as well as industry fora such as the UK Biotechnology Association.  Face to 
face meetings were planned but disrupted by changes in government leadership.  Silence has participated in initiatives 
aiming  to  enhance  the  environment  for  commercial  clinical  trials  in  the  UK  led  by  Lord  O'Shaughnessy  as  well  as 
contributing  to  the  agenda  and content of  an  oligonucleotide  workshop  to  be  organised  by  the  European  Medicines 
Agency,  due  to  be  held  in  early  2023.   The  aim  of  the  workshop  will  be  to  issue  development  guidance  for 
oligonucleotides which currently fall between guidance for small molecules and biologics. 

Employees 

W
.K. and Berlin  and in 2022 we 
achieved  certification  in  the  U.S.  We  foster  a  culture  in  which  upward  communication  and  feedback  is  valued  and 
encouraged. Silence recognises that flexibility positively impacts employee productivity, commitment and loyalty, so we 
have focused on building a diverse and inclusive culture and believe in trying to assist staff to achieve a good balance 
between their work and home life.   

We provide private medical insurance to all employees for acute medical conditions to cover full out-patient treatment, 
therapies, mental health support, dentist and optician cashback and extra cancer cover as a taxable benefit. 

We have also introduced several new health and wellbeing programmes to our employees in 2022.  For example, we 
now pay for all employees to have a subscription to the app-based wellbeing programme called Headspace.  We also 
introduced a new Employee Assistant program with the aim to give people access to 24/7 advice and help in personal 
and work-related matters. 

Throughout 2022, Silence provided support for patient advocacy partners, including 
walk  in  June  where  Silence  employees  collectively  walked  10,349  kilometres  and  raised  £10,349  for  our  partner 
charities.  

19 

 
 
 
 
 
 
SILENCE THERAPEUTICS PLC 

Environment 

We are monitoring our production processes and investigating new ways to increase the efficiency and reduce the mass 

and better work-from-home practices.  

Gender of Directors and Employees 

As of 31 December 2022, we had 122 employees. Of these employees,  93 employees are engaged in research and 
development activities and 29 employees are engaged in general and administrative activities. We have no collective 
bargaining agreements with our employees and we have not experienced any work stoppages. 

Diversity 

Appointments  within  the  Group  are  made  on  merit  accounting  to  the  balance  of  skills  and  experiences  offered  by 
prospective candidates. Whilst acknowledging the benefits of diversity, individual appointments are made irrespective 
of personal characteristics such as race, disability, gender, sexual orientation, religion or age. 

A breakdown of the employment statistics on the basis of employees as at 31 December 2022 is as follows: 

Gender Identity 

Directors* 
Senior Leadership** 
Other employees 

Female    

Male   

  Non-Binary    

-     
5     
61     

6   
9   
47   

-     
-     
-     

Did Not 
Disclose 
Gender  

-  
-  
-  

*Of the Directors, there are two executive directors, that are considered both a director and an employee. 

**Senior Leadership includes Department Heads and Vice Presidents. 

Human Rights 

The Group supports the UN Universal Declaration of Human Rights and recognises the obligation to promote universal 
respect for and observance of human rights and fundamental freedoms for all, without distinction. The Group complies 
with all applicable human rights laws. 

Companies Act 2006, s.172 Compliance 

The Company is required to provide information on how the directors have performed their duty under section 172 of 
the Companies Act 2006 to promote its success, including how the interests of its stakeholders have been taken into 
account in Board discussions and decision-making; stakeholders include: 

Investors 
The interests of its shareholders have been taken into account on a fair basis. This is described in more detail 
in "Relations with shareholders" in the Corporate Governance Report on page 29. The Company has a frequent 
and transparent dialogue with its investors throughout the year. Meetings take the form of roadshows, investor 
conferences and one-on-one dialogue as required. 

  Regulators 

Good dialogue is maintained with regulatory agencies and the Board  ensures our clinical trials are designed 
appropriately to allow the maximum potential for our products in development. 

20 

 
 
 
 
 
     
      
  
  
   
      
 
  
 
 
    
  
 
    
  
   
  
   
  
   
  
 
 
SILENCE THERAPEUTICS PLC 

  Suppliers 

identify  suppliers  with  the  right  profile  and  capabilities.  Good  relationships  are  kept  with  suppliers;  high 
standards are expected in product and service, and the Company reciprocates by paying on a prompt basis, 
within agreed terms. We  meet  with our significant suppliers regularly, monitoring  the  quality of products and 
services on a constant basis to ensure that there is no negative impact or delays on our research programmes. 

  Employees 
The Boa
with  employees.  Appropriate  remuneration  and  incentive  schemes  are  maintained  to  align  employees' 
objectives with those of the Company. As a result, the Company has a high staff retention rate. More detail on 
how  the  board takes  into  account the  interests  of  employees  can  be  found  in  the Remuneration  Committee 
report on page 37. 

  Community & Environment 

Policies  are  being  formulated  with  emphasis  on  matters  like  carbon  footprint,  for  example  holding  virtual 
meetings where possible rather than travelling between our sites in the U.K., Germany and U.S. Diversity in the 
workplace is actively encouraged. The Company has policies on anti-slavery and anti-bribery which are actively 
promoted. 

The Board focuses on maintaining high standards of business conduct. The Company operates  a Code of Business 
Conduct and Ethics and provides mechanisms for whistle blowing and complaints. 

The directors 

The strategic report has been approved by the Board and is signed on its behalf by: 

Craig Tooman 

Chief Executive Officer 

21 

 
 
 
 
SILENCE THERAPEUTICS PLC 

Board of Directors 
Our  Board  is  comprised  of  eight  accomplished  members,  two  Executive  and  six  Non-Executive  Directors. 
Together, they bring highly valuable experience across a variety of relevant disciplines to effectively execute 
our business plan. 

Iain Ross 
Chairman 
Appointed April 2019 

Iain Ross has over 40 
technology sectors and has held significant 
roles in multi-national companies including Sandoz, Hoffman La Roche, Reed Business Publishing and Celltech Group 
plc. He has completed multiple financing transactions, and has over 30 years  experience in cross-border management 
as a chairman and CEO. He has led and participated in eight Initial Public Offerings (IPOs) and has direct experience 
of M&A transactions in Europe, the United States and the Pacific Rim. Currently he is Executive Chairman of ReNeuron 
Group plc (LSE) and Non-Executive Chairman of Kazia Therapeutics Limited (ASX & Nasdaq). In addition, he is a non-
executive director of BiVictriX Therapeutics plc (LSE) and advises a number of private companies in the biotechnology 
sector. He is a qualified Chartered Director and Fellow of Royal Holloway, London University. 

Areas of Expertise 
Corporate Strategy, M&A, Business Development and Governance 

Current External Roles 
ReNeuron Group plc, Kazia Therapeutics Limited and BiVictriX Therapeutics plc  

Craig Tooman 
Executive Director 
Appointed February 2022 

Craig Tooman has served as our President, Chief Executive Officer and as a member of our Board since February 2022 
and previously served as our Chief Financial Officer from January 2021 until February 2022. Mr. Tooman has experience 
in the biopharmaceutical industry spanning more than 30 years, including 15 years of experience as a public company 
CEO  and  CFO.  Prior  to  joining  us,  from  September  2019  to January  2021,  he  served  as  CFO  and  COO  at  Vyome 
Therapeutics, Inc. and prior to his tenure at Vyome, from November 2013 to July 2019, Mr. Tooman served as CFO, 
and then subsequently as CEO and Board Director of Aratana Therapeutics, Inc., where he successfully negotiated a 
merger with Elanco. Before Aratana, from 2005 to 2010, Mr. Tooman served as the CFO of Enzon Pharmaceuticals, 
Inc.  until  its  acquisition  by  Sigma  Tau,  and  prior  to  that  led  the  $1.1  billion  M&A  initiative  and  integration  of  ILEX 
Oncology,  Inc.  and  Genzyme  Corporation.  Mr.  Tooman  has  also  held  key  positions  at  Pharmacia,  and  Upjohn.  Mr. 
Tooman currently serves on the Supervisory Board, and the Audit and Remuneration Committees of CureVac. He also 
serves on the Board of Directors of Ondine Biomedical Inc. and Verté Therapeutics. Mr. Tooman received a BA degree 
in Economics from Kalamazoo College and studied at Waseda University in Tokyo as part of that programme. He earned 
his MBA in finance from the University of Chicago. 

Areas of Expertise 
Leadership, Global Commercialisation, Strategy, Business Development, Biotech build 

Current External Roles 
CureVac and Ondine Biomedical Inc. 

Giles Campion 
Executive Director 
Appointed May 2020 

Giles Campion, M.D. is our Head of R&D and Chief Medical Officer, having joined Silence in June 2019.  

22 

 
 
 
 
 
 
SILENCE THERAPEUTICS PLC 

He is an expert in translational medicine and a highly experienced biotech and pharmaceutical professional across many 
therapeutic  areas,  most  recently  in  orphan  neuromuscular  disorders.    He  has  held  senior  global  research  and 
development roles in several large pharmaceutical, diagnostics and biotech companies, including responsibilities at the 
board  level.    Dr.  Campion  served  as  Chief  Medical  Officer  for  Albumedix  Ltd  from  January  2017  to  July  2018.    He 
previously served as Group Vice President, Neuromuscular Franchise at BioMarin  Pharmaceutical Inc.,  or BioMarin, 
Prosensa  Holding  N.V.,  or  Prosensa.    Dr. 
Campion served as Chief Medical Officer and Senior Vice President of Research and Development at Prosensa from 
2009 until its acquisition by BioMarin.  Dr. Campion has also served as medical advisor to MyoTherix Inc and is a co-
founder of PepGen Ltd.  Dr. Campion hold bachelors and doctorate degrees in medicine from the University of Bristol 
and is listed on the General Medical Council (UK) Specialist Register (Rheumatology). 

Areas of Expertise 
Pharmaceutical Research and Development, Rare Disease Development, Translational medicine  

Current External Roles 
Co-Founder of PepGen Ltd. 

Dave Lemus 
Non-Executive Director 
Appointed June 2018 

Dave Lemus currently serves as non-executive director of Sorrento Therapeutics Inc. (NASDAQ: SRNE), Scilex Holding 
Company (NASDAQ: SCLX)  and  BioHealthInnovation, Inc. Mr.  Lemus  was  previously  the  Chief  Executive Officer of 
Ironshore Pharmaceuticals Inc. and prior to this, Mr. Lemus served as Chief Operating Officer and Chief Financial Officer 
of Medigene AG. From 2011 to  2015,  he served as  Chief  Executive Officer of Sigma Tau  Pharmaceuticals, Inc. Mr. 
Lemus was also Chief Financial Officer and Executive Vice President of MorphoSys AG from 1998 to 2011, during which 
t
Mr. Lemus received an M.S. from the Massachusetts Institute of Technology and received a B.S. in accounting from the 
University of Maryland College Park. Mr. Lemus is also a Certified Public Accountant in the United States.  

Areas of Expertise 
Drug Commercialisation, Strategic Partnerships, Corporate Financing 

Current External Roles 
Lemax LLC (CEO), Sorrento Therapeutics Inc., Scilex Holding company, and BioHealth Innovation Inc. 

James Ede-Golightly 
Non-Executive Director 
Appointed April 2019 

James Ede-Golightly is currently chairman of Oxehealth Ltd, East Balkan Properties Plc and Oxford Advanced Surfaces 
Ltd. Among other directorships, Mr. Ede-Golightly is non-executive director of Sarossa plc, Serendipity Capital Ltd and 
Plant  Health  Care  plc,  and  has  extensive  experience  as  a  non-executive  director  of  AIM-quoted  companies  with 
international business interests. Mr. Ede-Golightly was a founder of ORA Capital Partners in 2006, having previously 
worked  as  an  analyst  at  Merrill  Lynch  Investment  Managers  and  Commerzbank.  Mr.  Ede-Golightly  is  a  CFA 
Charterholder  and  holds  an  M.A.  degree  in  economics  from  Cambridge  University.  In  2012,  he  was  awarded  New 
Chartered Director of the Year by the Institute of Directors.  

Areas of Expertise 
Investment and Corporate Finance 

Current External Roles 
Dunheved Limited, East Balkan Properties plc, Oxehealth Limited, Oxford Advanced Surfaces Limited, Sarossa plc, 
and Serendipity Capital Limited 

23 

 
 
 
 
SILENCE THERAPEUTICS PLC 

Alistair Gray 
Senior Independent Non-Executive Director 
Appointed November 2015 

Alistair Gray currently serves as non-

-executive 
director of Scottish Golf Ltd. Mr. Gray is also a founder and director of Renaissance & Company, a strategic management 
consultancy firm. Mr. Gray previously held senior management positions with Unilever and John Wood Group PLC, and 
he also chaired the Audit and Remuneration committees of AorTech International PLC and Highland Distillers PLC. Mr. 
Gray entered strategic management consulting at Arthur Young (now EY) Management Consultants and PA Consulting 
Group, where he served as a director for over ten years. Mr. Gray also served as a Fellow of the Institute of Directors 
and Institute of Consultants. He graduated from the University of Edinburgh in Mathematics and Economics, following 
this with a management accounting qualification. He is a member  of  the  faculty  of  Strathclyde  Business  School  and  
 Manufacturing and Engineering Management department. He is also 

a Visiting Professor at Loughborough University London and the University of Stirling. 

Areas of Expertise 
Strategic management, Organisation Performance and Governance 

Current External Roles 
Non-
Board and Scottish Golf Ltd. Founder/Director of Renaissance & Company. He is a member of the faculty of Strathclyde 

department. He is also a Visiting Professor at Loughborough University London and the University of Stirling. 

Dr. Steven Romano 
Non-Executive Director 
Appointed July 2019 
Dr.  Romano  is  a  pharmaceutical  executive  and  board-certified  psychiatrist  with  over  28  years  of  drug  development 
experience across a wide range of therapeutic and disease areas. Dr. Romano most recently served as executive vice 
president  and  chief  scientific  officer  at  Mallinckrodt  plc,  where  he  had  responsibility  for  research  and  development, 
regulatory, safety sciences and medical affairs. Prior to joining Mallinckrodt, Dr. Romano spent 16 years at Pfizer, Inc. 
where he held a series of senior research and development and medical roles of increasing responsibility, culminating 
in his most recent position as SVP, Head, Global Medicines Development, Global Innovative Pharmaceuticals Business. 
He has recently served as Chairman of the National Pharmaceuticals Council, a health policy research organization, 
and is a past president of the International Society for CNS Clinical Trials and Methodology, an independent organization 
focused on enhancing therapeutic development of central nervous system therapeutics. Dr. Romano graduated from 

University of Missouri-Columbia School of Medicine and completed his psychiatry and fellowship at Weill Cornell Medical 
Center, where he held academic and clinical positions prior to entering the industry. 

Areas of Expertise 
Research and Development, Regulatory, and Medical Affairs 

Current External Roles 
Non-executive director of Evolution Research Group. 

24 

 
 
 
 
 
SILENCE THERAPEUTICS PLC 

Michael Davidson, MD 
Non-Executive Director 
Appointed January 2021 

Michael H. Davidson, MD, FACC, FNLA, is Professor of Medicine and Director of the Lipid Clinic at the University of 
Chicago.  He also serves as Chief Executive Officer of New Amsterdam Pharma. Dr. Davidson is a leading expert in the 
field  of Lipidology. He  has  conducted over  1000 clinical trials,  published  more than  350  medical  journal articles  and 
written three books on Lipidology. His research background encompasses both pharmaceutical and nutritional clinical 
trials including extensive research on statins, novel lipid-lowering drugs, and omega-3 fatty acids.  Dr. Davidson is a 
serial biotech entrepreneur, founding three companies, the Chicago Center for Clinical Research, which became the 
largest  investigator  site  in  the  United  States  and  was  acquired  by  Pharmaceutical  Product  Development  in  1996, 
Omthera Pharmaceuticals in 2008, which was acquired by AstraZeneca in 2013 for $440 million, and most recently, he 
was the founding CEO/CSO of Corvidia Therapeutics, which was acquired by Novo Nordisk for up to $2.1 billion in 2020. 
In August 2020, he became the founding CEO of New Amsterdam Pharma based in Amsterdam and Adventura, Florida. 
New Amsterdam was listed on Nasdaq (NAMS) in November 2022. He is also in independent director of Nasdaq-listed 
Tenax Therapeutics and serves on the board of two private biotech companies, Sonothera and NanoPhoria Biocience. 
Dr. Davidson is board-certified in internal medicine, cardiology, and clinical lipidology.  He was President (2010-2011) 
of the National Lipid Association, named as one The Best Doctors in America for the past 20 

Diabetes Association, 2010. 

Areas of Expertise 
Lipidology and Clinical Development 

Current External Roles 
NewAmsterdam Pharma B.V., SonoThera, Inc., Tenax Therapeutics and NanoPhoria srl 

25 

 
 
 
SILENCE THERAPEUTICS PLC 

Introduction 

continues to be to maximize the potential of our proprietary mRNAi GOLD  platform by building 
a pipeline of both wholly owned and partnered programmes. Our wholly owned programmes focus and leverage our 
internal expertise in specific areas with the most opportunity while our partnered programmes provide collaboration for 
a broader reach and potential source for non-dilutive capital. We believe this hybrid business model balances risk and 
creates more opportunities.  

During the year, we continued to expand our institutional shareholder base, a key priority for us following the November 
2021 AIM delisting. In December 2022, institutional ownership accounted for 44% of our total ADSs outstanding vs. only 
27%  in  December  2021.  This  growing  institutional  interest  was  highlighted  during  our  August  2022  $56.5  million 
registered direct offering - an oversubscribed deal led by new U.S. healthcare investment funds. During the year, we 
also made steady progress towards improving our liquidity profile - average ADS trading volume more than doubled in 
2022 vs. 2021. We expect this positive momentum to continue into 2023 as we advance in the clinic.   

mRNAi GOLD  Proprietary Programmes 

SLN360 for cardiovascular disease  
SLN360 is our lead wholly owned siRNA in phase 2 development for high lipoprotein(a), a genetic cardiovascular risk 
 In December 2022, SLN360's INN (international non-proprietary 

name) was approved 

 zerlasiran.  

Phase 1 programme (APOLLO) 
In February 2022, we reported positive results from the single-ascending dose portion of the APOLLO phase 1 
programme 
the top two SLN360 single dose groups (300 mg and 600 mg) had up to 96% and 98% median reduction in Lp(a) 
levels, respectively, and median reductions of up to 71% and 81% from baseline persisted at 150 days. Those 
receiving a placebo saw no change in Lp(a) levels. In April 2022, results from the APOLLO single dose study were 
simultaneously presented at the American College of Cardiology (ACC) Annual Meeting and published in The Journal 
of the American Medical Association (JAMA). In November 2022, we presented a further analysis up to 365 days from 
the APOLLO single dose study in a moderated poster session at the American Heart Association (AHA) Annual 
Meeting. The assessment showed participants who received a single dose of SLN360 maintained median Lp(a) 
reductions over 80% over a five-month period. Additionally, extension data to day 365 showed no new drug related 
safety findings. We expect data from the multiple dose portion of the APOLLO programme in the fourth quarter of 
2023. 

Phase 2 programme (ALPACAR-360) 
After the end of the year, on January 12, 2023, we announced that the first subjects have been dosed in the 
ALPACAR-360 phase 2 study of 
expect to complete enrolment in the study in the fourth quarter of 2023. 

-risk of ASCVD events. We 

We plan to partner SLN360 prior to initiation of a phase 3 cardiovascular outcomes study and potential 
commercialization. These partnering discussions are ongoing and remain a top priority. 

SLN124 for hematological diseases  
SLN124 is our second wholly owned siRNA that has shown potential in several hematological diseases. SLN124 is 
currently in clinical development for polycythemia 
TMPRSS6 

In March 2022, SLN124 was granted FDA orphan drug designation in PV. In September 2022, the FDA granted 
SLN124 Fast Track Designation for PV. SLN124 has FDA orphan drug designation and rare pediatric disease 
designation for beta-thalassemia. The European Medical Agency also granted SLN124 orphan drug designation and 
rare pediatric disease designation for beta-thalassemia. 

Polycythemia Vera 

 SANRECO phase 1/2 programme 

26 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
SILENCE THERAPEUTICS PLC 

 GEMINI II phase 1 programme 

After the end of the year, on January 12, 2023, we announced that sites were open for enrolment in the SLN124 
phase 1/2 PV study. The SLN124 PV study is a two-part study which includes a phase 1 open-label, dose finding 
study followed by a phase 2 randomized, double-blind, placebo-controlled parallel arm study. 
Thalassemia 
In September 2022, we announced positive preliminary safety results from the single-ascending dose portion of the 
GEMINI II study in non-transfusion dependent thalassemia patients. SLN124 was well tolerated with no serious AEs, 
no severe TEAEs that were SLN124 related and no TEAEs leading to withdrawal. No dose limiting toxicity or drug 
related liver injury was observed. Effects on hepcidin, serum iron, transferrin saturation and hemoglobin are being 
evaluated in the ongoing multiple-dose arm expected to readout in the fourth quarter of 2023.  

mRNAi GOLD  Partnered Programmes 

AstraZeneca 
During the year, we continued work with AstraZeneca on two undisclosed targets. We started our collaboration in 
March 2020 and received an upfront cash payment of $60 million. We have the potential to receive up to $4 billion in 
potential milestones plus royalties for a total of 10 targets. 

Mallinckrodt 
In March 2022, we achieved a $3.0 million milestone payment from Mallinckrodt following the submission of the 
clinical trial application for SLN501, our siRNA targeting C3 for complement-mediated diseases. In June 2022, we 
started dosing in the SLN501 phase 1 study in healthy volunteers. We are working with Mallinckrodt on two other 
undisclosed complement targets which are progressing on-track. We started our collaboration in July 2019 and 
received an upfront cash payment of $20 million. We have the potential to receive up to $2 billion in potential 
milestones plus royalties for the 3 targets. 

Hansoh 
In April 2022, we achieved our first $2 million research milestone in our Hansoh Pharma collaboration. In this 
partnership, we have exclusive rights to two targets in all territories except the China Region (Greater China, Hong 
Kong, Macau and Taiwan) and Hansoh has global rights to a third target. We started our collaboration in October 
2021 and received an upfront payment of $16 million. We have the potential to receive up to $1.3 billion in potential 
milestones plus royalties. In December 2022, we initiated work on the second target which we retain global rights to 
outside the China Region. 

Great Place to Work certified 

certified in the United States. We foster a culture in which upward communication and feedback is valued and 
encouraged. Silence recognizes that flexibility positively impacts employee productivity, commitment, and loyalty, so 
we have focused on building a diverse and inclusive culture and believe in trying to assist staff to achieve a good 
balance between their work and home life.  

Organizational change 
In February 2022, we were pleased to appoint Craig Tooman who previously served as our Chief Financial Officer as 
President, Chief Executive Officer and Board member. We were also pleased to appoint Rhonda Hellums, previously 
our VP, Finance, as Chief Financial Officer.  

Commitment to sustainability and high standards of governance 
RNAi continues to be an exciting space with huge potential to disrupt the treatment of multiple genetic diseases and I 
believe Silence will play a key role in the future of this important therapeutic area. To maximise this opportunity, we 
recognise the critical importance of promoting a culture of inclusion and diversity. Currently at the Board level, we 
have one self-identified member of the LGBTQ+ community and another Silence director identified as a member of the 
Latinx community. Good science depends upon recruiting a mix of patients into our clinical trials reflective of the 
overall population and good business depends upon diverse representation across our organisation, especially in 
leadership positions.  

The Board is also committed to Corporate Social Responsibility, ensuring that we continue to make a positive impact 
on the world. We have made great strides in three areas in which we will aim to pursue our ambition to drive positive 
change for the communities around us: Social, Community & Human Rights, Employees and Environment. More 

27 

 
 
 
 
 
 
 
 
 
 
 
SILENCE THERAPEUTICS PLC 

details on our Corporate Social Responsibility initiatives can be found in the Corporate Social Responsibility section of 
this Annual Report 

Iain Ross 
Chairman 

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SILENCE THERAPEUTICS PLC 

Corporate Governance Report  

The Directors remain committed to maintaining high standards of transparency, ethics and corporate 
governance. 

What corporate governance standards does the Company follow? 

In  July  2018,  the  Board  approved  the  application  of  The  Quoted  Companies  Alliance  (QCA)  Corporate  Governance 
Code (2018 edition) (the QCA Code). While the Company is no longer required to comply with the QCA code as the 
Company is no longer listed on AIM, the Company has voluntarily continued to comply, where applicable, through the 
reporting period. The QCA Code is a practical, outcome-oriented approach to corporate governance that is tailored for 
small  and  mid-size  quoted  companies  in  the  UK.  The  Board  views  this  as  an  appropriate  corporate  governance 
framework for Silence Therapeutics plc and consideration has been given below to each of the ten principles set out in 
the QCA Code. 

How frequently does the Board meet? 

The Board holds four scheduled meetings per year, aligned with quarterly management reporting; regular monthly Board 
update calls and additional meetings and Board calls when circumstances and urgent business dictate. In the 12-month 
period under review, there  were 12 meetings. The high number of Board meetings was driven by the introduction of 
regular monthly Board update calls to keep Board members fully updated on business developments.  

Type of meeting 

Board 

Audit and Risk Committee 

Remuneration Committee 

Nomination Committee* 

   Number of meetings   

12 

8 

4 

0 

Craig Tooman  appointment as CFO were both discussed and agreed upon at Meetings of the full Board 

All Board and Audit and Risk Committee meetings  were fully attended by the relevant Directors throughout the year 
either in person or virtually; two Remuneration Committee meetings were not attended by Dr. Michael Davidson. All 
Directors  receive  the  agenda  and  Board  papers in advance  of  Board  meetings to enable them  to make  an  effective 
contribution. Between Board meetings, the Chairman maintains regular informal contact with Non-Executive Directors. 
The Board continues to meet on a regular basis in order to review progress and agree strategy. 

The  Board  reviews  the  strategy  and  at  each  meeting  evaluates  the  progress  of  the  Company  towards  achieving  its 
annual objectives. It also analyses the risk of potential activities and monitors financial progress against budget. 

-Executive Director and 

How does the Board apply the ten principles set out in the QCA Code? 

1. Establish a strategy and business model which promote long-term value for shareholders 

To support the execution of this strategy, the Board performs the following key tasks: 

statement on page 26. 

  approval of long-term objectives and strategy; 

  approval of revenue, expense and capital budgets and plans; 

  approval for therapeutic candidate progression through key development and clinical stages; 

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SILENCE THERAPEUTICS PLC 

  oversight  of  operations  ensuring  that  adequate  systems  of  internal  controls  and  risk  management  are  in  place, 
ensuring maintenance of accounting and other records, and compliance with statutory and regulatory obligations; 

review of performance in light of strategy and budgets ensuring that any necessary corrective actions are taken; 

review progress towards and consider options and terms of business development and corporate collaboration and 
development deals; 

  approval  of  the  annual  report  and  financial  statements,  half  year  results,  material  contracts  and  major  projects; 

changes to structure, size and composition of the Board; 

  determining remuneration policy for the Directors and approval of the remuneration of the Non-Executive Directors; 

and 

  approval of communications with shareholders and the market. 

2. Seek to understand and meet shareholder needs and expectations 

Contact with major shareholders has been principally maintained by the  CEO and the Chairman during the reporting 
period, and they have ensured that their views are communicated to the Board as a whole. The Board believes that 
appropriate steps have been taken during the reporting period to ensure that the members of the Board, and in particular 
the Non-Executive Directors, develop an understanding of the views of major shareholders about the Company. 

Whilst we are aiming to hold our Annual General Meeting in April, a Notice of Annual General Meeting will be issued in 
due course and will be available on our website. Separate resolutions will be provided on each issue so that they can 
be given proper consideration. Proxy votes are counted and the level of proxies lodged on each resolution reported after 
it has been dealt with by a show of hands. 

3. Take into account wider stakeholder and social responsibilities and their implications for long-term 
success 

 ability to help patients and their caregivers to be highly important and critical to the 
The Board considers the 
long-term success of Silence. For more information on how the 
 lead drug candidates, SLN124, SLN360 and 
SLN501,  can  help  patients,  refer  to  pages  6  to  16.  Our  Sustainable  Development  Goals  including  goals  related  to 
community, health and environment, are set out on page 19. 

4. Embed effective risk management, considering both opportunities and threats, throughout the organisation 

A Risk Register is maintained for regular review by the Audit and Risk Committee and the Board. Principal risks are set 
out on page 18 where mitigating activities are also explained. 

Additionally, the Audit and Risk Committee report on page 35 sets out how risks are reviewed. 

5. Maintain the Board as a well-functioning, balanced team led by the Chairman 

Currently  the  Board  has  a  majority  of  Non-Executive  Directors,  consisting  of  two  Executive  and  six  Non-Executive 
Directors
The skillsets of the Board include extensive knowledge of the pharmaceutical and biotechnology industries, strategic 
consultancy and corporate finance. 

The Nomination Committee is chaired by the Chairman of the Board, Iain Ross.  

Craig  Tooman  was  appointed  as  CEO  on  February  21,  2022
background are given in their biographies on pages 22 to 25. 

The Chairman is responsible for leading the Board and ensuring its effectiveness and is responsible for the operational 
management of the Company and implementation of Board strategy and policy. 

The Board delegates certain activities to the Committees, with terms of reference which are available on the Company 
website (www.silence-therapeutics.com). Membership of all three Board Committees comprises a Non-Executive Chair 
and at least two other Non-
expense, professional advice on any matter within their terms of reference and to have access to sufficient resources in 
order to carry out their duties. 

30 

 
 
 
 
 
 
SILENCE THERAPEUTICS PLC 

Board Structure 

Following  the  appointment  of  Craig  Tooman  as  CEO  in  February  2022,  the  Board  Committee  memberships  are  as 
follows:   

Audit and Risk Committee 

Dave Lemus (Chair) 

Alistair Gray 

James Ede-Golightly 

Dr. Michael Davidson 

Remuneration Committee 

James Ede-Golightly (Chair) 

Dr. Michael Davidson 

Dave Lemus 

Dr. Steven Romano 

Nomination Committee 

Iain Ross (Chair) 

Alistair Gray 

Dr. Steven Romano 

Craig Tooman 

6. Ensure that between them the directors have the necessary up-to-date experience, skills and capabilities 

The Board has delegated the tasks of reviewing Board composition, searching for appropriate candidates and making 
recommendations  to  the  Board  on  candidates  to  be  appointed  as  Directors,  to  the  Nomination  Committee. 
The Nomination Committee chair is held by the Chairman of the Company. 

The main duties of the Nomination Committee are set out in its terms of reference and include: 

regularly  reviewing  the  structure,  size  and  composition  (including  the  skills,  knowledge,  experience  and 
diversity) required of the Board compared to its current position and making recommendations to the Board 
with regard to any changes; 

determining the qualities and experience required of the 
and identifying suitable candidates, assisted where appropriate by recruitment consultants; 

 Executive and Non-Executive Directors 

formulating plans for succession for both Executive and Non-Executive Directors and in particular for the key 
roles of Chair and Chief Executive Officer; 

assessing the re-appointment of any Non-Executive Director at the conclusion of their specified term of office, 
having given due regard to their performance and ability to continue to contribute to the Board in the light of 
the knowledge, skills and experience required; and 

assessing the re-election by shareholders of any Director, having due regard to their performance and ability 
to continue to contribute to the Board in the light of the knowledge, skills and  experience required and the 
need for progressive refreshing of the Board. 

Craig  Tooman  was  appointed  as  CEO  and  Executive  Director  in  February  2022.  With  regard  to  the  re-election  of 
Directors, the Company is governed by its Articles of Association (the Articles). Under the Articles, the Board has the 
power to appoint a Director during the year, but any person so appointed must stand for election at the next Annual 
General Meeting. Any Director who has been a Director at each preceding two Annual General Meetings and has not 
been appointed or re-appointed since, must retire from office at the next Annual General Meeting. 

31 

 
 
 
 
 
 
 
 
SILENCE THERAPEUTICS PLC 

The Director is then eligible to stand for re-appointment by the shareholders. Steven Romano will stand for re-election 
at the 2023 Annual General Meeting. 

The annual performance evaluation for 2021, resulted in recommendations, which are being implemented by the Board, 
to allocate more time at Board meetings to consider business development and opportunities to grow the business. 

Silence is committed to diversity in all aspects of its mission and activities and at all levels of the organisation, including 
its Board of Directors. The Board understands the value in having directors of diverse gender, race, and ethnicity, along 
with varied skills,  perspectives and experiences. We are constantly looking for opportunities to improve our diversity 
and inclusion practices. 

7. Evaluate Board performance based on clear and relevant objectives, seeking continuous improvement 

The Silence Therapeutics plc Board remains mindful that it needs to continually monitor and identify ways in which it 
might  improve  i
effectiveness. 

A review of the CEO was initiated and concluded in January 2023. The CEO reviewed the performance of the CFO for 
2022. Any performance-related remuneration is determined by the Remuneration Committee and recommended to the 
Board.  

The  Directors,  led by  the Senior Independent Non-Executive Director, 
performance. 

In  conducting  the  formal  annual  evaluation,  the  Board  undertakes  a  rigorous  assessment  of  its  own  performance, 
balance  of  skills,  experience,  independence,  diversity  (including  gender  diversity)  and  other  factors  relevant  to  its 
effectiveness (and also that of its Committees) and the performance of its individual Directors. In late 2022 the Board 
commenced a formal  evaluation  of its performance  which  was concluded  in  Q1  2023. In  conducting this review,  the 
Chairman and the Senior Independent Director undertook discussions with each of the other Directors regarding the 

In  preparation,  the  Chairman  and the  Senior  Independent  Non-Executive  Director, solicited  the  views  of  the  other 
Directors, including the completion by each Director of a confidential questionnaire in respect of the Board, the Audit 
and Remuneration Committee and one specifically relating to the performance of the Chairman. The Senior Independent 
Non Executive Director had individual discussions with the Directors about the  performance of the Chairman. In the 
case  of  the  Directors,  all  questionnaires  were  returned  to  the  Senior  Independent  Non-Executive  Director,  who 
summarised the overall assessment of each director.  

Following  the  reviews,  the  Chairman  and the  Senior  Independent  Non-Executive  Director, shared  their  observations 
with the other Directors at a Board Meeting in Q1 2023 during which an open feedback session was held in an executive 
session of the Non-Executive Directors. The individual director evaluations were aimed to confirm that each Director 
continues both to contribute effectively and to demonstrate commitment to the role (including the allocation of necessary 
time for preparation and attendance at Board and Committee meetings and any other duties). 

The results of the review were satisfactory overall, actions emerged which can be summarised as follows: 

  Strategy  and  Contingency  Planning - As 

in-house 
capabilities and corresponding operational infrastructure globally, it was agreed that there should be more emphasis 
at Board meetings on strategic discussions and risk analysis and in addition that the annual strategy session for the 
Board of  Directors  should  be  expanded  to  include  external  and  professional  input. External  environment  we  are 
likely to  face should also  be considered, both metric  based  and  qualitative.  Also, the Board and  its Committees 
should pro-actively consider, review and assess contingency scenarios on a regular basis.   

the  Company  expands 

its development pipeline, 

  Succession Planning - as the Company expands it was agreed that the Board needs to formalise its approach to 
Board & Management succession planning in terms of skills, geography and diversity. The Chairman is committed 
to lead this initiative in liaison with the CEO.  In addition, be open and transparent around any concern about conflict 
of interest if, and when, that exists. 

  Non-Executive  Directors  ongoing  training  and  development  and  interaction  with  senior  management  - 
Following a concerted effort led by the Chairman and the Senior Independent Non-Executive Director, this will be 
implemented to introduce a more structured approach to the induction and broader development of Directors and 
interaction with the Senior Management on a more frequent basis to enhance their knowledge and understanding 
of  the  business  as  it  evolves.  Further, each  Committee  should  be  given  the  challenge  to  modernize,  in  light  of 
changes in regulation and capital markets and other external issues which many include potential changes in scope 
of the committee.   

32 

 
 
 
 
SILENCE THERAPEUTICS PLC 

The Nomination Committee is responsible for succession planning and making recommendations to the Board in this 
respect, as set out above. 

8. Promote a corporate culture that is based on ethical values and behaviours 

Ethical values and behaviours are important to the Company and the Company is dedicated to driving positive change 
for communities around the world. The policies to implement this are explained on page 19.  

9. Maintain governance structures and processes that are fit for purpose and support good decision-making by 
the Board 

The  Board  is  supported  by  the  Committees,  explained  above,  in  the  task  of  maintaining  good  practice  governance 
processes and structures. Furthermore, the following governance matters support good decision-making by the Board. 

Internal Controls and Risk Management 

The  Company  has  in  place  a  system  of  internal  financial controls  commensurate  with  its  current  size  and  activities, 
which is designed to ensure that the possibility of misstatement or loss is kept to a minimum. These procedures include 
the preparation of management accounts, variance analysis, controls in place for one-off accounting items and other ad 
hoc  reports.  In  2022  the  Group  engaged  EisnerAmper  as  consultants  to  test  ICFR  (Internal  controls  over  financial 
reporting).  As  a  result,  the  Group  was  able  to  build  up  of  evidence  from  an  internal  control  perspective  and  allow 
management to attest over the ICFR as required under the Sarbanes-Oxley Act 2002.  

Risks  throughout  the  Company  are  considered  and  reviewed on a  regular  basis.  Risks  are  identified  and  mitigating 
actions put into place as appropriate. Principal risks and uncertainties identified are set out in the strategic report on 
pages 18 and 19. 

Internal  control  and  risk  management  procedures  can  only  provide  reasonable  and  not  absolute  assurance  against 
material misstatement. 

Financial and Business Reporting 

 position and prospects in 
The Board seeks to present a balanced and understandable assessment of the 
all half year, full year and price-sensitive reports and other information required to be presented by statute. The Board 
receives  a  number  of  reports  to  enable  it  to  monitor  and  clearly  understand  the 
  financial  position.  The 
Company maintains a Disclosure Policy to enhance the process for ensuring that price-sensitive information is identified 
effectively and all communications with the market are released in accordance with expected timescales. 

Conflicts of Interest 

Under the Articles of Association, the Directors may authorise any actual or potential conflict of interest a Director may 
have and may impose any conditions on the Director that are felt to be appropriate. Directors are not able to vote in 
respect of any contract, arrangement or transaction in which they have a material interest and they are not counted in 

This includes declaring any new conflicts at the start of each Board meeting. 

Board Advice 

All the Directors have access to the advice and services of the Company Secretary, who is responsible for ensuring that 

with. Each Director is 
Company 

10. Communicate how the company is governed and is performing by maintaining a dialogue with shareholders 
and other relevant stakeholders 

Contact with major shareholders is principally maintained by the Chairman and CEO, and additionally as necessary the 
Senior Independent Non-Executive Director  is available to discuss governance and other matters directly with major 
shareholders, both private and institutional. 

33 

 
 
 
 
 
SILENCE THERAPEUTICS PLC 

The  Company  uses  its  corporate  website  (www.silence-therapeutics.com)  to  communicate  with  institutional 
shareholders and private investors, and the website also contains the latest announcements, press releases, published 
financial information, current projects and other information about the Company. The annual report which includes the 

Iain Ross 
Chairman 

34 

 
 
 
  
 
 
 
SILENCE THERAPEUTICS PLC 

Audit and Risk Committee Report 

heightened focus on all aspects related to company financings, internal controls and additional financial reporting 
requirements. 

asdaq 

Dave Lemus 
Chair of the Audit and Risk Committee 

Who are the members and who do they interact with? 

Dave Lemus is Chair of the Audit and Risk Committee. 

Dave currently also serves as audit committee chair of Sorrento Therapeutics, Inc. (Nasdaq: SRNE) and Scilex Holding 
Company (Nasdaq: SCLX), and previously served on multiple public and private company boards as a non-executive 
board member in his more than 25 years of experience in the biopharmaceutical industry.   Most recently he was CEO 
of  Ironshore  Pharmaceuticals,  Inc.,  and  has  been  previously  a  CEO,  COO  and  CFO  in  several  public  and  private 
companies in the U.S and in Europe.  Dave is also a Certified Public Accountant in the USA 

In  addition  to  Dave,  the  members  of  the  committee  comprise  Alistair  Gray,  James  Ede-Golightly  and  Dr.  Michael 
Davidson. The Committee met eight times during 2022, including prior to results announcements. 

What does the Audit and Risk Committee do? 

  Monitors enterprise and systemic risks 

  Reviews accounting policies and key estimates and judgements 

  Reviews the appropriateness and completeness of the internal controls 

  Makes recommendations to the Board, to be put to shareholders for approval at the Annual General Meeting, 

in relation to the appointment, re-

  Meets with the external auditors, ensuring that they report to it on all relevant matters to enable the Committee 

to carry out its oversight responsibilities 

? 

financial statements, preliminary announcements and any other 
 In  2022, the  Committee reviewed  the  2021 
annual  report  and  the  2022  interim  announcements.  The  Committee  reviews  and  challenges  where  necessary  any 
changes  to,  and  the  consistency  of,  accounting  policies,  advising  whether  the  Company  has  followed  appropriate 
accounting standards and made appropriate estimates and judgements (notably in respect to the adoption of any new 
accounting  pronouncements,  the  accounting  of  the  partnership  agreements  and  financings,  and  the  impairment  of 
investments in subsidiaries), taking into account the views of the external auditors, the going concern assumption and 
all material information presented with the financial statements. 

What does the Committee do to review risks? 

To assess the appropriateness and completeness of internal controls, the Committee reviews changes to the detailed 
risk matrix which identifies high level control issues classifi
are subject to, remedial action. The Committee considers whether the necessary actions are being taken to remedy any 
significant failings or weaknesses. 

Is there an internal audit function? 

35 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
SILENCE THERAPEUTICS PLC 

At present the Company does not have an internal audit function. Given the Nasdaq listing, the Company will need to 
be compliant  with  additional  Sarbanes-Oxley  requirements  over a  period  of time,  this will initially be achieved by in-
house initiatives supported by external specialists. However, the Committee will review the need for an internal audit 
function  at  least  annually.  With  the  Nasdaq  listing,  the  Committee  has  a  new  responsibility  to  review  the  system  of 
internal financial control and compliance with the US Sarbanes Oxley Act 2002. In 2022, EisnerAmper was appointed 
he ICFR (Internal controls over financial reporting). 
As  a  result,  the  Group  was  able  to  acquire  sufficient  evidence  from  an  internal  control  perspective  and  allow 
management to attest over the ICFR as required under the Sarbanes Oxley Act 2002.  

Who are the external auditors and how long have they been appointed? 

PricewaterhouseCoopers  LLP  were  appointed  as  the  external  auditors  in  2014.  The  Committee  reviews  industry 
comparables for audit services and evaluates the overall service provided by the external auditors each year. Having 

LLP be re-

How  does  the  Audit  and  Risk  Committee  assess  the  effectiveness  of  the  external  audit 
process? 

The Committee oversees the relationship with the external auditors, including approval of their remuneration, approval 
of their terms of engagement, annual assessment of their independence and objectivity, taking into account relevant 
professional and regulatory requirements, and the relationship with the auditors, as a whole, including the provision of 
any non-audit services. The breakdown of fees between audit and non-audit services is provided in note 5 to the financial 
statements. The auditors prepare an Audit Plan for the audit of the full year financial statements, which was presented 
to the Committee and discussed in August 2022. The Audit Plan sets out the scope of the audit, areas to be targeted 
and the audit timetable. Following the audit, the auditors present their findings to the Committee for discussion. 

Review  of  Accounting  and  Financial  Reporting  Matters  and  Matters  of  Significance  and 
Judgement 

The Committee received reports from management and the external auditor setting out the significant accounting and 
financial reporting matters and judgements applicable to the following key areas. Following discussion and challenge, 
the Committee reviewed management's conclusions on certain significant company accounting policies, which included 
but were not limited to:  

R&D costs related to CROs including associated accruals and prepayments  
In determining the R&D expense in relation to contract research organisations (CROs) management have estimated the 
total percentage of completion of each contract to date and included consideration of future costs to be incurred.   These 
estimates have also been used in determining accruals and prepayments at the year end.  

Accounting for Revenue (collaboration agreements)  
In  determining  the  revenue  recognised  for  collaboration  agreements,  management  have  calculated  the  revenue 
recognised for the period based on the percentage of completion of each performance obligation, by determining the 
proportion of costs incurred to date in comparison to the total expected costs (both internal and external). 

Carrying value of the investment in Silence Therapeutics GmbH (to parent company) 
Different  methodologies can be used  to determine the  carrying value  of  this  investment. In determining  the carrying 
erapeutics GmbH management assessed it as being based 
the Company has had to estimate the 

value and timing of future milestone cash inflows, which is however a standard industry practice. 

Committee  aims to ensure appropriate corporate compliance  with all  accounting, internal controls, risk management 
and  financial  reporting  requirements  and  in  order  to  best  ensure  the  Committee  is  carrying  out  its  oversight 
responsibilities to the fullest extent possible.  

Dave Lemus 
Chair of the Audit and Risk Committee 

36 

 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
SILENCE THERAPEUTICS PLC 

Remuneration Committee Report 
Having the right team to execute on an internationally competitive strategy in the fast-moving field of RNAi is 
a key priority for the Board and the Company. 

James Ede-Golightly 

Chair of the Remuneration Committee 

Dear Shareholder, 

for the year ended 31 December 2022. 

Having the right team to execute on an internationally competitive strategy in the fast-moving field of RNAi is a key issue 
for the Board and the Company. Craig Tooman has served as our President, Chief Executive Officer and as a member 
of our board of directors since February 2022 and previously served as our Chief Financial Officer from January 2021 
until February 2022. Craig was instrumental in expanding the shareholder base with new US investors as well as leading 
the  delisting  of  the  Company  from  AIM  in  November  2021.  Craig  has  experience  in  the  biopharmaceutical  industry 
spanning more than 30 years, including 15 years of experience as a public company CEO and CFO. In February 2022 
we also appointed Rhonda Hellums as our Chief Financial Officer. She previously served as our Vice President, Finance 
since joining in April 2021. Rhonda has over 25 years of corporate finance, accounting, strategic planning, M&A, treasury 
management,  investor  and  public  relations  experience,  largely  in  the biopharmaceutical  industry.  Though  she  is  not 
listed as a U.K director, she sits in on all board meetings.  

We continue to deliver a remuneration programme that rewards both achievement of short-term goals and fulfilment of 
our longer-term objectives, linked with the ultimate exploitation of our platform and its application in generating novel 
RNAi medicines. We recognise the need to retain and motivate Executive Directors and the senior management team 
and  avoid  making  remuneration  decisions  solely  based  on  shorter-term  volatility.  Accordingly,  we  include  two 
performance-based elements in our remuneration programme: a shorter-term annual bonus programme, with payment 
-set goals for that year; and a longer-term equity-based 
programme of share options, vesting over four years and directed towards the achievement of substantial, longer-term 
strategic  objectives.  The  short-term  programme  and  the  long-term  incentive  programme  are  providing  a  balance 
designed  to  incentivise  Executive  Directors  and  senior  management  to  work  toward  achievement  of  the  corporate 
strategy. 

During the year, share options were awarded to Craig Tooman, Rhonda Hellums and Giles Campion; vesting dates for 
these options are detailed later in this report.  

In light of our de-listing from AIM and the transition to a Nasdaq-focused company, in 2022 we have adopted a new 
compensation strategy for Non-
in order to attract and retain top international talent. 

This remuneration policy has the intention of ensuring that Silence is in line with biotech industry best practices. 

James Ede-Golightly 
Chair of the Remuneration Committee  

37 

 
 
 
SILENCE THERAPEUTICS PLC 

Remuneration Policy 

This part of the remuneration report sets out the D

The remuneration policy was approved by shareholders in a binding vote at the AGM on  15 June 2021. Thereby, as 
intended the remuneration policy will remain in effect from the date of approval and apply for a maximum period of three 
years (or until a revised policy is approved by shareholders). 
Remuneration report were approved at the AGM with 98% votes for / 2% votes against / 0% votes withheld.  

was 

Philosophy: Support value creation for shareholders over the longer term and create alignment with shareholders 

Fixed Remuneration 

Variable Remuneration 

Element 

Base Salary 

Benefits 

Pension 

Annual Bonus 

LTIP 

How it is influenced 
by the remuneration 
philosophy 

Assessed with 
reference to industry 
compensation 
benchmarks 

Assessed with 
reference to industry 
compensation 
benchmarks 

Assessed with 
reference to industry 
compensation 
benchmarks 

Set considering industry 
benchmarking data and 
consistent with positions 
held. 

The more significant 
element of the package 
linked to longer-term 
share performance. 

Determined by corporate 
and individual targets that 

goals and its overall 
strategy. 

Under the Silence 
Therapeutics plc 2018 
employee LTIP, share 

options can be issued with 
performance criteria under 
this scheme. 

In developing its policy, the Committee has regard to the policy for remuneration of employees across the  Company.  
The D
does  not  engage  in  a  wider  consultation  with  employees  on  the  policy.    Remuneration  across  the  Company  is 
implemented in the following ways: 

  All employees are rewarded with a remuneration package that includes certain key benefits such as life assurance, 
private medical insurance, 401(k) matching, access to pension benefits (or cash in lieu), and eligibility to receive a 
bonus.  All employees are e
to ensure that levels of remuneration for all key employees are up to date and competitive within the sector. 

  The  bonus  scheme  for  our  Executive  Directors  and  employees  are  designed  to  reward  performance,  and  all 

individuals work towards challenging corporate and individual goals. 

In setting the remuneration policy for Directors, the pay and conditions of other employees are taken into account, 
including any base salary increases awarded. The Committee is provided with data on the remuneration structure 
for management level tiers below the level of Executive Director and uses this information to ensure consistency of 
approach throughout the Company.   The views of  share

shareholders  in  advance  of  making  any  material  future  changes  to  remuneration  arrangements  for  Executive 
Directors. 

The  remuneration  of  senior  executives  below  Board  level  is  reviewed  by  the  Committee  on  an  annual  basis. 
The remuneration packages of these executives are broadly consistent with the policy outlined above, with the overall 
impact  of the role  and the  individual  being  considered  as well as  relevant  market comparative data, save  that lower 
bonus percentages and lower share option opportunities are applicable. 

A copy of the 

 can be found on the Com

38 

 
 
 
 
 
 
 
 
 
 
 
SILENCE THERAPEUTICS PLC 

Remuneration Policy Table 

Executive Directors 

Purpose and 
Link to Strategy  Operation 

Base Salary 

To attract and 

The Committee aims to set base 

salary at levels that are broadly 
aligned with the mid-points for 
equivalent roles in comparable 
global companies, adjusted to 
reflect Company size and 
complexity. 

Salaries are normally reviewed 
annually, and changes are 
generally effective from 1 
January. 

The annual salary review of the 
Executive Directors takes into 
consideration a number of factors, 
including: 

  business performance; 

salary increases awarded to 
the overall employee 
population; 

skills and experience of the 
individual over time; 

responsibilities; 

changes in the size and 
complexity of the Company; 

  market competitiveness and 

UK, European and US 
market practice; and 

the underlying rate of 
inflation. 

retain executives 
of the highest 
calibre who are 
capable of 
delivering the 
Company
strategic 
objectives, 
reflecting the 

experience and 
role within 
the Company. 

Base salary is 
designed to 
provide an 
appropriate level 
of fixed income to 
avoid an over-
reliance on 
variable pay 
elements that 
could encourage 
excessive risk 
taking. 

Benefits 

Benefits in kind 
offered to 
Executive 
Directors are 
provided on a 
market-
competitive basis, 

to assist with their 
recruitment and 
retention. 

Pensions 

Maximum Opportunity 

Performance Metrics 

No formal metrics, although any increases 

take account of Company performance and 
Executive Director appraisal 
against objectives. 

No clawback will be applied in relation to 
salaries. 

Executive Director level salaries are 
determined considering industry 
benchmarking data. 

Base salary increases are awarded at the 
discretion of the Committee; however, 
salary increases will normally be no 
greater than the inflationary pay rises 
awarded to the wider workforce. 

Executive Director level salaries are 
approved by the Committee in line with 
corporate performance and are consistent 
with the role currently being undertaken by 
the individual. 

The Company aims to offer 
benefits that are in line with 
market practice. 

The value of each benefit is not 
predetermined and is based upon the 
taxable value to the individual. 

Not performance related. 

No claw-back will be applied in relation to 
benefits. 

39 

 
 
 
 
 
 
 
 
 
 
 
 
SILENCE THERAPEUTICS PLC 

Executive Directors 

Purpose and 
Link to Strategy  Operation 

Maximum Opportunity 

Performance Metrics 

The Company operates a defined 
contribution scheme and all 
employees, including Executive 
Directors, are invited to 

Employee contributions are matched two-
fold by employer contributions up to a 
maximum employer contribution of 10%. 
Employees may contribute more than 5% 

participate. 

Cash payments in lieu of pension 
contributions may be made. 

themselves, but the Company will not 
provide any further employer contributions 
above this level. 

Not performance related. 

No claw-back will be applied in relation to 
pensions. 

The Company 
aims to provide 
market- 
competitive 

retirement 
benefits, as a 
retention tool and 
to reward 
sustained 
contribution. 

Annual cash bonuses are limited to a 
target of 50% or 60% of base salary for the 
Executive Directors. 

Executive Director level bonuses are 
approved by the Board in line with 

corporate performance and are consistent 
with the role currently being undertaken by 
the individual. 

The Board can exercise discretion in 
setting contractual bonus rates for new 
Executive Directors above 60%, with 
discretion exercised with respect to total 
compensation. 

Corporate goals typically include 
development of pipeline and platform, 
partnering successes, revenue generation, 
strengthening of intellectual property and 
control of cash expenditure, although the 

Committee has the discretion to set other 
targets. 

Individual goals set are specific, 
measurable and are linked to the 
-term strategy. 
Company

Under the rules of the scheme, the 
Committee can claw-back up to 100% of 
the bonus awarded in the event of material 

results, an error in assessing the 
performance conditions to which an award 
is subject or for any other matter which 
it deems relevant.  There is no claw-back 

time limit in the policy. 

Annual Performance Bonus 

An annual cash 
bonus rewards 
the achievement 
of objectives that 
support the 

Objectives are agreed with the 
Committee, and the Board, at the 
start of each financial year 
although the Committee retains 
the discretion to amend objectives 

Company
corporate goals 
and delivery of the 
business strategy. 

during the year if it considers that 
objectives are no longer 
appropriate. 

Different performance measures 
and weightings may be used each 
year, as agreed with the 
Committee, to consider changes 
in the business strategy. 

Bonuses are paid at the discretion 
of the Committee. The Committee 
considers overall corporate 
performance and individual 
performance when determining 

the final bonus amount to be 
awarded and the Committee may 
adjust any formulaic outcomes 
accordingly. 

Bonuses are normally paid in 
cash (but may be paid in the form 
of an equity award) typically 
in January or February. 

Long Term Incentive Plan (LTIP) 

40 

 
 
 
 
 
 
 
 
 
SILENCE THERAPEUTICS PLC 

Executive Directors 

Purpose and 
Link to Strategy  Operation 

LTIP awards granted to Executive 
Directors have typically taken the 
form of nominal cost options 
vesting according to performance 

conditions measured over at least 
three years, although different 
forms of awards may also be 
granted in accordance with the 
LTIP rules. 

The 
Remuneration 
Committee 
believes that a 

key component of 
the overall 
remuneration 
package is the 
provision of equity 
awards to senior 
executives 
through an LTIP, 
which is designed 
to develop a 
culture which 
encourages 
strong corporate 

performance on 
an absolute and 
relative basis to 
align with 
shareholder 
interests. 

Maximum Opportunity 

Performance Metrics 

Aggregate options outstanding will vest at 
up to a maximum of 300% of annual salary 
within a single financial year. 

Vesting of LTIP awards is generally subject 
to continued employment and may also be 
subject to the achievement of performance 

Executive Director level LTIP awards are 

approved by the Committee in line and are 
consistent with the role currently being 
undertaken by the individual. 

The Committee can exercise discretion in 
setting contractual LTIP awards for new 
Executive Directors above 250% of annual 
salary with discretion exercised with 
respect to total compensation. 

strategic plan. Measures, their weightings 
and the period over which performance is 
tested will be determined by the Committee. 

The Committee has the discretion to utilise 
differing types of performance criteria, 
measures and performance periods for future 
option grants, should it believe they are more 
relevant. 

The Committee may adjust the formulaic 
LTIP outcome to ensure it takes account of 
any major changes to the Company (e.g. as 
a result of M&A activity) and is a fair 
reflection of the underlying financial 

performance of the Company over the 
performance period. 

Further details, including the performance 
targets attached to the LTIP in respect of 
each year, will be disclosed in the relevant 
Annual Report on Remuneration. 

Awards will be subject to claw-back where 
there has been a misstatement of the 

property, an error in assessing the 
performance conditions to which an award is 

subject or for any other matter which the 
Committee deems relevant. There is a two-
year claw back time limit in the policy. 

41 

 
 
 
 
 
 
  
 
 
SILENCE THERAPEUTICS PLC 

Chair and Non-Executive Directors 

Purpose and Link 
to Strategy 

Cash Fees 

Set at a level that is 
sufficient to attract and 
retain high-calibre non-

executives who 
contribute to 
the business. 

Benefits 

Set at a level that is 
sufficient to attract and 
retain high-calibre non-
executives who 
contribute to 
the business. 

Equity Based Awards 

Set a level that is 
sufficient to attract and 
retain high-calibre non-
executives who 
contribute to 
the business. 

Operation 

Maximum opportunity 

Performance Metrics 

The Chair and the Non-Executive Directors receive 
fees paid in cash. 

Fees are paid monthly and reviewed annually. 

When reviewing fee levels, 
account is taken of market 
movements in the fees of Non-

Executive Directors, Board 
Committee responsibilities and 
ongoing time commitments. 

Not performance related. 

No claw-back applies in 
relation to fees. 

Since 1 January 2018 Non-Executive Directors do not 
receive any benefits in connection with their roles 
other than Company life insurance and 
reimbursement of travel costs for attendance at 
Board meetings. This may be reviewed in the future.  

When reviewing benefits, 
account is taken of market 
movements in the fees of Non-
Executive Directors, Board 
Committee responsibilities and 
ongoing time commitments. 

Not performance related. 

No claw-back applies in 
relation to benefits. 

The Non-Executive Directors may be offered the 
opportunity to participate in the Silence Therapeutics 
plc 2018 Non-Employee LTIP in the form of non-
performance restricted stock units or other equity 
awards under the terms of such plan with careful 
consideration being made with respect to ensuring 
their independence. 

When reviewing equity-based 
awards, account is taken of 
market movements in the fees 
of Non-Executive Directors, 
Board Committee 
responsibilities and ongoing 
time commitments. 

Not performance related. 

Claw-back applies in relation 
to equity-based awards. 

42 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
       
SILENCE THERAPEUTICS PLC 

Other Remuneration Policies 

Termination and Loss of Office Payments 
The 
  policy  on  remuneration  for  Executive  Directors  who  leave  the  Company  is  consistent  with  general 
market practice and is set out below. The Committee will exercise its discretion when determining amounts that should 
be paid to leavers, considering the facts and circumstances of each case. When calculating termination payments, the 
Committee will consider a variety of factors, including individual and Company performance, the length of service of the 
Executive Directors in question and, where appropriate, the obligation for the Executive Directors to mitigate loss.  In 
the  event of  a  change of  control and ownership, the Committee  may  exercise  its discretion  to  provide  for  additional 
remuneration and/or benefits for Executive Directors who leave the company in connection with such change of control 
and will take into account all relevant circumstances when making any such determination.  

  notice period of six months unless contractually longer, and pension and contractual benefits, or payment in lieu of 

notice; 

  statutory redundancy payments will be made, as appropriate; 

  executives have no entitlement to a bonus payment in the event that they cease to be employed by the Company; 

however, they may be considered for a pro-rated award by the Committee in good leaver circumstances;  

  any  share-

contracts or share option plans will be determined based upon the relevant individual share option contracts or plan 
rules; and performance conditions or hurdles; and 

the Committee may also provide for the leaver to be reimbursed for a reasonable level of legal  fees in connection 
with a settlement agreement, to be paid ex gratia amounts in settlement of claims and in respect of other ancillary 
matters such as amounts in respect of outplacement services, relocation, and health benefits (continuation or cash 
in lieu). 

Service Contracts 

It is the Company

The Executive Directors may accept outside appointments, with prior Board approval, provided that these opportunities 
do not negatively impact on their ability to fulfil their duties to the Company. Whether any related fees are retained by 
the individual or are remitted to the Company will be considered on a case-by-case basis. 

Non-

Terms of Engagement 

All Non-Executive Directors 
notice by either party. 
either party. 

The remuneration of Non-Executive Directors is determined by the Board within the limits set by the Articles and based 
on a review of fees paid to Non-Executive Directors of similar companies. 

A Board evaluation has been performed and the results of this exercise confirmed that all Non-Executive Directors were 
independent. 

Remuneration for New Appointments 

Where it is necessary to recruit or replace an Executive Director, the Committee has determined that the new Executive 
Director will receive a compensation package in accordance with the provisions of the Policy. 

In setting base salaries for new Executive Directors, the Committee will consider the existing salary package of the new 

In  setting the annual  performance  bonus, the  Committee  may wish  to set different performance  metrics  (to those of 
other Executive Directors) in the first year of appointment. Where  it is appropriate to offer  a below-median salary on 
initial appointment, the Committee will have the discretion to allow phased salary increases over a period of time for a 

43 

 
 
 
 
 
 
 
SILENCE THERAPEUTICS PLC 

newly appointed Director, even though this may involve increases in excess of inflation and the increases awarded to 
the wider workforce. 

The  Committee  wishes  to  retain  the  ability  to  make  buy  out  awards  to  a  new  Executive  Director  to  facilitate  the 
recruitment process. The amount of any such award would not exceed the expected value being forfeited and, to the 
extent possible, would mirror the form of payment, timing and degree of conditionality. Where awards are granted subject 
to performance conditions, these would be relevant to Silence Therapeutics plc. Any such award would only be made 
in exceptional circumstances and shareholders would be informed of any such payments at the time of appointment. 
Share-based awards would be made under the LTIP. 

In respect of internal appointments, any commitments entered in respect of a prior role, including variable pay elements, 
may be allowed to pay out according to their prior terms. 

For  external  and  internal  appointments,  the  Committee  may  consider  it  appropriate  to  pay  reasonable  relocation  or 
incidental expenses, including reasonable legal expenses. Tax equalisation may be considered if a Director is adversely 
affected by taxation due to their employment or engagement with the Company. 

The  terms  of  appointment  for  a  Non-Executive  Director  would  be  in  accordance  with  the  remuneration  policy  for 
Non-Executive Directors as set out in the policy table. 

Remuneration Committee (the Committee) 

Governance 

In its decision-making process, the Committee takes account of information from both internal and independent sources 
and  AON  Solutions  UK  Ltd  surveys.  AON  Solutions  UK  Ltd  were  appointed  as  remuneration  consultants  by  the 
Committee based on their expertise in the field. AON Solutions UK Ltd advises the Committee on all aspects of senior 
executive remuneration and has kept the Committee up to date on remuneration trends and corporate governance best 
practice.  AON  Solutions  UK  Ltd  does  not  have  any  other  connection  with  the  Company  and  is  considered  to  be 
independent by the  Committee.  During  the  year  ended 31 December 2022, fees charged  by  AON  Solutions UK Ltd 
amounted to approximately £71k (2021: £79k).  

The current members of the Committee are Michael Davidson, James Ede-Golightly, Dave Lemus and Steven Romano. 
Michael Davidson, James Ede-Golightly and Dave Lemus are deemed to be independent.   

The  Company
the  Committee,  as  required,  to  ensure  that  the  Committee  is  fully 
informed about pay and performance issues throughout the Company. The Committee takes these factors into account 
when determining the remuneration of the Executive Directors and senior executives. 

No Executive Director or employee can participate in any discussion directly relating to their own personal conditions of 
service or remuneration. 

No conflicts of interest have arisen during the year and none of the members of the Committee has any personal financial 
interest in the matters discussed, other than as option holders.  The fees of the Non-Executive Directors are approved 
by the Board on the joint recommendation of the Committee and the Chief Executive Officer. 

The Committee met 4 times in 2022. 

Director 
James Ede-Golightly 
Michael Davidson 
Dave Lemus 
Steven Romano 

Role 

Meetings attended   
4/4   
4/4  
4/4   
3/4   

 strategy by ensuring that those individuals responsible 
 remuneration policy. 
for delivering the strategy are appropriately incentivised through the operation of the 
In determining the 
 current policy, and in constructing the remuneration arrangements for Executive Directors 
and  senior  employees,  the  Board,  advised  by  the  Committee,  aims  to  provide  remuneration  packages  that  are 

44 

 
 
 
 
  
  
  
 
 
  
  
  
  
 
SILENCE THERAPEUTICS PLC 

competitive and designed to attract, retain and motivate Executive Directors and senior employees of the highest calibre, 
and align incentives with shareholder interest. 

The Committee is responsible for: 

  setting a remuneration policy that is designed to promote the long-term success of the Company; 

  ensuring that the remuneration of the Executive Directors and other senior executives reflects both their individual 

performance and their contribution to the overall Company results; 

  determining the terms of employment and remuneration of the Executive Directors and senior executives, including 

recruitment and retention terms; 

  approving the design and performance targets of any annual incentive schemes that include the Executive Directors 

and senior executives; 

  approving the design and performance targets, where applicable, of all share incentive plans requiring shareholder 

approval; 

rigorously assessing the appropriateness and subsequent achievement of the performance targets related  to any 
share incentive plans; 

recommending to the Board the fees to be paid to the Chair. The Chair is excluded from this process; 

  gathering and analysing appropriate data from comparator companies in the biotech sector; and 

the selection and appointment of the external advisers to the Committee to provide independent remuneration advice 
where necessary. 

Pay-for-Performance Scenario Analysis 

The charts below provide an estimate of the potential reward opportunities for the Executive Directors, and the potential 
split between different elements of remuneration under two 

Earned  

45 

 
 
 
 
 
 
 
 
SILENCE THERAPEUTICS PLC

Craig Tooman

Compensation

7000

6000

5000

4000

3000

2000

1000

0

£5,290 

222
1
12
408

Earned

1
12
408

Minimum - Fixed

Salary

Benefits

Pension

Bonus

LTIP

Giles Campion

Compensation

1800

1600

1400

1200

1000

800

600

400

200

0

£1,017 

158
35
9
350

Earned

35
9
350

Minimum - Fixed

Salary

Benefits

Pension

Bonus

LTIP

Mark Rothera (Executive Director term ending February 21, 2022)

46

SILENCE THERAPEUTICS PLC

Compensation

4500

4000

3500

3000

2500

2000

1500

1000

500

0

£3,254 

167
15
47
554

Earned

15
47
554

Minimum - Fixed

Salary

Benefits

Pension

Bonus

LTIP

Amounts are shown in thousands (GBP).

The LTIP award amounts shown represents the aggregate grant date fair value of option awards granted in 2022 measured using the Black Scholes model.

47

SILENCE THERAPEUTICS PLC 

Annual Report on Remuneration 
This  section  of  the  Remuneration  report  provides  details  of  how  our  remuneration  policy  was  implemented  during  the 
financial year ended 31 December 2022, and how it will be implemented during the year ending 31 December 2023.  

This report splits certain information into that for Executive Directors and that for Non-Executive Directors.   

Audited Information 

 financial year ended 31 December 2022 

The total remuneration of the individual Directors who served during the period is shown below. Total remuneration is the 
sum of emoluments for the period in service as a director plus Company pension contributions, and the value of long-term 
incentive awards vesting by reference to performance in the twelve months to 31 December 2022.  

Basic 
Salarya 

Benefits
b 

Bonusc  

LTIPd   

Pension
e 

Total 
remuneratio
n 

Total fixed 
remuneratio
n 

Year  

£000s   

£000s   

£000s  

£000s    £000s   

£000s   

£000s   

Total 
variable 
remuneratio
n 
£000s  

Executive 
Directors 

Craig Tooman (f) 

2022   

        408    

12    

        222   

5,290     

1    

5,910    

421    

5,489  

Mark Rothera (g) 

Giles Campion 

Non-Executive 
Directors 
Iain Ross 

Alistair Gray 

Dave Lemus 

James Ede-
Golightly 

Dr Steven Romano  

Dr Michael 
Davidson 

2021   
2022   
2021   
2022  

2021   
2022   
2021   
2022   
2021   
2022   

2021   
2022   
2021   
2022   

2021   
2022   

426     
554     
321     
350   

153    
47    
-    
9   

204  
167  
129  
158  

375      
3,254      
975      
1017    

54     
15     
32     
35     

1,212     
4,037     
1,457     
1,569     

120     
90     
55     
54     
55     
46     

55     
44     
55     
37     

54     
40     

-    
-    
-    
-    
-    
-    

-    
-    
-    
-    

-    
-    

-  
-  
-  
-  
-  
-  

-  
-  
-  
-  

-  
-  

840      
458      
-      
244      
-      
244      

-      
244      
-      
244      

-      
244      

-     
-     
-     
-     
-     
-     

-     
-     
-     
-     

-     
-     

960     
548     
55     
298     
55     
290     

55     
288     
55     
281     

54     
284     

633     
616     
353     
394     

120     
90     
55     
54     
55     
46     

55     
44     
55     
37     

54     
40     

579  
3,421  
1,104  
1,175  

840  
458  
-  
244  
-  
244  

-  
244  
-  
244   

-  
244   

Notes to the Remuneration Table  

(a)  This is the amount earned in respect of the financial period.  

(b)  This is the taxable value of benefits paid or payable in respect of the financial period. For Non-Executive Directors, 
the taxable benefits comprise travel costs (and the gross-up for associated income tax and 
National 
Insurance  Contributions  which  will  be  settled  on  behalf  of  the  Non-Executive  Directors)  for  attendance  at  Board 
meetings.  

(c)  For 2022, this is the total bonus earned under the annual bonus scheme in respect of the financial year (despite 

being paid in the following financial year, following determination of final outcomes).  

(d)  For  2022,  the  amount  shown  represents  the  aggregate  grant  date  fair  value  of  option  awards  granted  in  2022 
measured using the Black Scholes model. For a description of the assumptions used in valuing these awards, see 
note 24 to our Annual Consolidated Financial Statements included elsewhere in this Annual Report. For 2021, the 
amount shown relates to the market value of the LTIP awards vesting during the year using the Co

48 

 
 
 
 
 
 
 
  
 
  
  
 
  
  
  
 
  
 
 
   
    
      
     
   
  
  
       
       
       
       
 
 
           
 
 
  
   
     
    
  
 
 
      
     
     
     
 
 
   
  
 
   
 
   
  
 
 
  
 
   
     
    
  
   
      
     
     
     
  
 
   
     
    
  
   
      
     
     
     
  
 
   
  
 
   
 
   
  
 
   
 
   
  
 
   
 
   
  
 
   
   
  
 
   
 
   
  
 
   
 
 
SILENCE THERAPEUTICS PLC 

closing price at the end of the quarter in which the award vested less associated exercise price. Total option award 
compensation  expense  for  the  year  ended  December  31,  2022  for  all  key  management  personnel  including the 
former CEO and non-executive directors was £3.5 million. 

(e)  The amount shown relates to company contributions to the defined contribution scheme, plus any cash in lieu. 

(f)  Mr.  Tooman  served  as  our  Chief  Financial  Officer  during  2021  and  became  our  President  and  Chief  Executive 
Officer on February 21, 2022. His compensation including, salary, bonus, pension and benefits, is prorated from the 
time of his appointment to Chief Executive Officer. 

(g)  Mark Rothera, our former President and Chief Executive Officer, stepped down on February 21, 2022. His salary is 
inclusive of severance payments, paid in instalments from his separation date for an additional 12 months in line 
with his severance agreement and his bonus payment was prorated from the start of the year until six months after 
his separation date in line with his severance agreement. 

Annual Performance Bonus - 2022  

In  2022,  all  employees  were  eligible  for  an  annual  discretionary  cash  bonus,  whereby  performance  objectives  are 
established at the beginning of the financial year by reference to suitably challenging corporate goals.  

In relation to the Directors, Craig To
for 2022 was 50% of salary, with a maximum potential of 60%.   

2022.  

-target bonus 

For all other staff (other than the Executive Directors and Non-Executive Directors) the maximum bonus opportunities 
ranged from 8% to 40% of salary, depending on grade. Bonus payments are not pensionable. 

For 2022 for all staff (other than the Executive Directors and Non-Executive Directors) the percentage attributable to 
individual goals for employees ranged from 30% to 70% depending on level (excluding the Executive Directors). 

In 2022, for Craig Tooman and Giles Campion 100% of their annual bonus was by reference to corporate goals. The 
achievement against the scorecard of corporate goals was as follows: 

Target 

   Weighting    

SLN 124 milestone delivery 
SLN 360 milestone delivery 
Advance collaboration programmes 
Manufacturing processes 

New GalNAc target identification 

  Achieve planned targets for the development of SLN 124      
  Achieve planned targets for the development of SLN 360      
  Advance collaboration targets into clinical development 
Increase capacity and build process optimisation 
capabilities for manufacturing  
Achieve planned activity and identification of new targets 

Achievement of financial targets 

Maintain a cash runway and adherence to budget 

New business development deal 

Secure high value business development deal 

Secure additional funding 

Bring in new US investors and non-dilutive funding 

Total 

2022 
achievement 
%   
14.0   
19.0   
6.0  

12.0  

%    
15.0       
20.0       
5.0       

10.0     

10.0       

10.0   

5.0     

6.0  

30.0     

17.0  

5.0       

100.0       

6.0   

90.0   

Achievement against objectives is given careful consideration by the Committee prior to finalisation.   The Committee 
acknowledged the team's significant progress in advancing our clinical-stage programmes in 2022, further financing key 
programmes, securing additional manufacturing capacity, and expanding the US investor base.  Therefore, the board 
determined an achievement score of 90% was fair and justifiable. 
The Committee reviewed the formulaic outcome of the scorecard and concluded that the scorecard outcome, as shown 
above, reflected the performance of the Executive Directors in the year. The resulting annual bonus awards under  the 
Policy, i.e. bonus awards of up to 60% of salary payable in cash, are as follows: 

49 

 
 
 
 
  
  
  
 
    
  
   
 
 
   
 
  
 
    
 
 
 
   
 
 
 
   
 
  
 
    
    
    
 
 
SILENCE THERAPEUTICS PLC 

Bonus Scorecard 
Outcome 

   Maximum opportunity 

% of salary 

Cash amount 

% of salary 

£000s     
222     
158     

54 %   
45 %   

£000s     
245     
210     

60 % 
60 % 

Craig Tooman 
Giles Campion 

Scheme Interests 

During the year ended 31 December 2022 Craig Tooman and Giles Campion were awarded share awards under the 
LTIP  scheme,  details  of  which  are  summarised  in  the  table  below.  LTIP  awards  were  granted  under  the  Silence 
Therapeutics plc 2018 Employee Long Term Incentive Plan and were based on an industry peer analysis. 

Directors share awards 

Individual  Date of Grant  At 1 Jan, 2022 

   Awarded        At 31 Dec 2022    

Exercise price 
($/share)) 

Gain on 
exercises 
during 
the year 
(£000s) 

Earliest date of 
exercise 

Last date of 
exercise 

Iain Ross 

10/06/2019  
10/06/2019  
21/05/2020  
21/05/2020  
06/01/2022  

250,000     
250,000     
150,000-     
350,000-     

-      
-      
-      
-      

90,000  

250,000     
250,000     
150,000     
350,000     
90,000    

$2.53     
$0.80     
$0.07     
$5.87     
$7.87    

-   
-   
-   
-   
-   

01/06/2020  
01/06/2020  
25/04/2022  
21/08/2020  
06/02/2022  

10/06/2029 
10/06/2029 
20/05/2030 
20/05/2030 
06/01/2032 

Alistair 
Gray 

06/01/2022 

Dave Lemus 

06/01/2022 

James Ede-
GoLightly 

06/01/2022            

06/01/2022 

06/01/2022 

Dr Steven 
Romano 

Michael 
Davidson 

Craig 
Tooman 

Giles 
Campion 

           48,000               48,000 

$7.87                                    

      06/02/2022 

         06/01/2032 

           48,000            48,000 

$7.87      

      06/02/2022 

         06/01/2032 

           48,000            48,000 

$7.87      

      06/02/2022 

         06/01/2032 

           48,000            48,000 

$7.87      

      06/02/2022 

        06/01/2032 

              48,000            48,000 

   $7.87       

       06/02/2022          

       06/01/2032 

06/01/2021  

579,999     

-      

579,999     

$7.02     

-   

06/01/2022  

06/01/2031 

06/01/2022  
21/02/2022  
16/09/2022  

06/03/2019  

10/06/2019  
10/06/2019  
10/06/2019  
23/04/2021  
06/01/2022  

264,999  
375,000  
900,000  

264,999         
375,000    
900,000    

200,000     

15,000     
228,083     
456,917     
160,002    
-    

-      

200,000     

-      
-      
-      
-  
199,998  

15,000     
228,083     
456,917     
160,002    
199,998    

$7.87    
$6.33    
$3.86    

$0.07     

$2.44     
$0.80     
$2.53     
$7.34    
$7.87    

06/02/2022  
21/03/2022  
16/10/2022  

06/02/2032 
21/03/2032 
16/10/2032 

-   

-   
-   
-   
-   

06/02/2022  

06/02/2029 

10/06/2022  
01/06/2020  
01/06/2020  
23/05/2021  
06/02/2022  

10/06/2029 
10/06/2029 
10/06/2029 
23/04/2031 
06/01/2032 

50 

 
 
 
  
  
  
    
  
  
  
    
  
  
  
    
  
  
  
  
  
  
  
  
  
  
    
     
    
  
  
  
  
  
  
  
  
  
  
  
   
  
  
 
   
   
      
       
       
      
    
   
 
 
 
 
    
  
  
  
   
      
       
    
       
    
   
        
  
   
 
 
  
    
      
   
      
   
  
        
  
   
 
 
  
    
      
   
      
   
  
        
  
   
 
 
  
    
      
   
      
   
  
        
  
   
 
 
  
    
      
   
      
   
  
        
  
    
 
 
  
    
      
   
      
   
  
 
     
     
   
 
    
  
   
 
    
  
   
  
  
   
      
       
    
       
    
   
 
 
 
 
  
 
  
   
 
  
    
  
  
    
    
   
  
 
SILENCE THERAPEUTICS PLC 

Scheme interests awarded in 2022 

Date of grant    Number awarded   

Exercise Price     

Iain Ross 
Alistair Gray 
Dave Lemus 
James Ede-
GoLightly 

Dr Steven 
Romano 
Michael Davidson 
Craig Tooman 
Craig Tooman 
Craig Tooman 
Giles Campion 

06/01/2022    
06/01/2022    
06/01/2022    

90,000   
48,000  
48,000  

06/01/2022    

48,000  

06/01/2022    

06/01/2022       
06/01/2022    
21/02/2022    
16/09/2022    
06/01/2022    

48,000  

48,000  
264,999  
375,000  
900,000  
199,998  

$7.87       
$7.87     
$7.87     

$7.87     

$7.87     

$7.87     
$7.87     
$6.33     
$3.86     
$7.87     

Face value (2) 
(£000s) 
-   
-  
-  

-  

-  

-  
-  
-  
£908  
-  

Vesting Schedule 

Note 3 
Note 3 
Note 3 

Note 3 

Note 3 

Note 1 
Note 1 
Note 1 
Note 4 
Note 1 

1.  Share options vest in 48 equal monthly vesting tranches starting from the month of grant. These awards are not subject to any performance conditions. 

2. Face value is equal to the share price at December 31, 2022 less that exercise price.  

3. Share options vest in 36 equal monthly vesting tranches starting from the month of grant. These awards are not subject to any performance conditions. 

4.  Share options vest in 60 equal monthly vesting tranches starting from the month of grant. These awards are not subject to any performance conditions. 

Directors' interests in shares at 31 December 2022 

Options: Total 
shares owned 
outright plus 
vested options 

 606,267        
 1,056,807        
 1,070,766        
 28,569        
 26,193        
 28,569 

 31,659 

 31,659 

Director 

Current directors        
Craig Tooman 
Giles Campion 
Iain Ross 
Alistair Gray 
Dave Lemus 
James Ede-
Golightly 
Dr. Steven 
Romano 
Dr. Michael 
Davidson 

Former director 
Mark Rothera (2) 

Shares Owned 
outright 

Percentage of 
issued share 
capital 

Options: Vested 
but not exercised 

Options: Unvested 
but subject to 
performance 

 31,986        
 23,943        
 64,941        
 9,903        
 7,527        
 9,903 

 12,993 

 12,993 

0.56%  
0.98%  
0.99%  
0.03%  
0.02%  
0.03% 

0.03% 

0.03% 

 574,281        
 1,032,864        
 1,005,825        
 18,666          
18,666          
 18,666   

 18,666   

18,666   

Options: 
Unvested and 
not subjected to 
performance1 

 3,645,717   
 484,791   
 174,168   
77,334     
 77,334     
 77,334 

 77,334   

 77,334   

-         

-         
-         

-         

-         

-    

-    

-    

-    

-  

331,111    

1.  Options unvested and not subject to performance exclude those options that will only vest if a floor condition is met 

2. 

The options expired in February 2023. 

Unaudited Information 
Performance Graph and Table 

to the Nasdaq Biotech Index.  

cumulative Total Shareholder Return (TSR) over the last five financial years relative 

ncludes 
dividends paid, the change in capital value of the shares and any other payment made to or by shareholders within the 
period. 

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SILENCE THERAPEUTICS PLC

160

140

120

100

80

60

40

Aligning Pay with Performance

CEO remuneration compared with annual growth in TSR:

SLN

NBI

The total 2022 remuneration figure for the CEO (Craig Tooman) is shown in the table below, along with the value of
bonuses paid in respect of the year, and fair value of options granted, as a percentage of the total remuneration. 

2022
Total remuneration

Actual bonus as a % of the remuneration
Actual share award as % of the remuneration

2021
Total remuneration

Actual bonus as a % of the remuneration
Actual share award vesting as % of the remuneration

Craig Tooman
£000s
5,910

4%
90%

Mark Rothera
£000s
1,212

17%
31%

*As 2021 was the first year reported since listing on NASDAQ and therefore the first year for which this disclosure is required, it is not possible to provide 

meaningful comparative data. However, full disclosure of the year-on-year movement will be provided in future remuneration reports.

Percentage Change in Remuneration of the Directors and Employees 

Set out below is the change over the prior period in base salary, benefits, pension and annual performance bonus for 

included below. The current CEO, Craig Tooman, is not included in the able above as he was appointed as a Director 
(Chief Executive Officer) on 21 February 2022 and therefore prior year data is not available. Former CEO, Mark Rothera 

52

SILENCE THERAPEUTICS PLC 

Is not included in the table above as he served as a Director until 21 February 2022 and therefore the prior period is not 
comparable. 

Giles Campion 
Iain Ross 
Alistair Gray 
Dave Lemus 
James Ede-Golightly 
Dr. Steven Romano 
Dr. Michael Davidson 
All employees excl. directors 

Giles Campion 
Iain Ross 
Alistair Gray 
Dave Lemus 
James Ede-Golightly 
Dr. Steven Romano 
Michael Davidson 
All employees excl. directors 

Giles Campion 
Iain Ross 
Alistair Gray 
Dave Lemus 
James Ede-Golightly 
Dr. Steven Romano 
Michael Davidson 
All employees excl. directors 

Salary % Change   
2021 vs 2022   

Benefits % Change   
2021 vs 2022   

Bonus % Change   
2021 vs 2022   

9 % 
-25 % 
2 % 
-16 % 
-20 % 
-26 % 
-33 % 
3 % 

Salary % Change   
2020 vs 2021   
Note 1  
Note 2   

22 % 
22 % 
22 % 
22 % 

N/A  

4 % 

Salary % Change   
2019 vs 2020   
Note 1  
Note 2   

13 % 
13 % 
13 % 
13 % 

N/A  

4 % 

100 % 

Note 2  
Note 3  
Note 3  
Note 3   
Note 3   
Note 3  

3 % 

Benefits % Change   
2020 vs 2021   
Note 1  

-100 % 

Note 3  
Note 3  
Note 3   
Note 3   
N/A  

3 % 

Benefits % Change   
2019 vs 2020   
Note 1  

100 % 
-100 % 
-100 % 

Note 3   
Note 3   
N/A  

3 % 

22 % 

Note 2   
Note 3   
Note 3   
Note 3   
Note 3   
Note 3  

4 % 

Bonus % Change   
2020 vs 2021   
Note 1  
Note 2   
Note 3   
Note 3   
Note 3   
Note 3   
N/A  

4 % 

Bonus % Change   
2019 vs 2020   
Note 1  
Note 2   
Note 3   
Note 3   
Note 3   
Note 3   
N/A  

4 % 

1. Giles Campion was appointed as a Director (Executive Vice President, Head of R&D and CMO) on 9 June 2020, therefore there is not a comparable change from 2020 
or prior. 

2. Iain Ross was appointed as Executive Chairman on 17 December 2019. Base salary included additional remuneration of £9 thousand (exclusive of VAT) relating to 
duties undertaken in December 2019 as Executive Chairman. This amount was billed by Iain 
2020. Iain Ross was paid £15 thousand (exclusive of VAT) on a monthly basis until one month following the appointment of a new CEO. In 2020, in recognition of the 
additional Executive responsibilities and in addition to his monthly Chairman/Director fees of £10 thousand per month Mr Ross was paid an additional remuneration of 
£15k per month invoiced through his consultancy firm Gladstone Consultancy Partnership for the period 1 January to - 31 May 2020. In the absence of a permanent CEO 
appointment, on 1 June Mr Ross signed an employment contract immediately terminable 1 month following the appointment of a new CEO. For the period 1 June - 14 
October  2020  Mr  Ross  was  paid  £30  thousand  per  month  plus  benefits  including  a  contribution  to  pension  and  private  healthcare  insurance  of  £3  thousand.  On  14 
September 2020 Mr Ross reverted to his role as Non-executive Chairman and from 1 month after this date reverted to his monthly fees of £10 thousand per month. On 
signing the employment agreement effective 1 June 2020 Mr Ross was paid a one-off bonus of £75 thousand in respect of services rendered 17 December 2019 - 31 May 
2020.  Upon completion of his time as Interim Executive Chairman Mr Ross was paid a further one-off bonus of £80 thousand in respect of services rendered during the 
remainder of his time in this Executive role. Throughout 2021, Iain maintained a salary of £10 thousand per month. He was not paid a bonus or benefits in either 2021 or 
2022.  

3. Non-executive directors were not entitled to a bonus in any year. They were not entitled to benefits in any year, with the exception of Alistair Gray and Dave Lemus 

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SILENCE THERAPEUTICS PLC 

who were paid benefits of £13 thousand and £2 thousand, respectively in 2019.  

Relative Importance of Spend on Pay 

Total revenue and research and development expenditure have been selected as comparators for the employee costs 
as these two financial measures are strong indicators of the activity within the Company and of its performance. 

Total employee remuneration 
Average number of employees 
Revenue 
Research and development expenditure 

2021   
£000     
21,279        

92     

12,415        
30,765        

2022   
£000     
26,875        
116        
17,501        
35,605        

Change   
£000   

26 % 
26 % 
41 % 
16 % 

No dividends distributions or share buyback transactions occurred in either 2021 or 2022.  

Statement of Implementation of Policy in 2022 

Base Salary: The January 2023 target base salary increase was and average of 3% for all eligible employees. There 

 base salary. 

Pension  and  Benefits:  In  2023,  Executive  Directors  are  eligible  for  the  same  benefits  as  provided  to  all  senior 
employees. The Executive Directors are each entitled to the maximum employer pension contribution of 10% of their 
respective  base  salary  which  is  paid  into  a  defined  contribution  pension  scheme  /  paid  in  cash  in  lieu  of  pension 
contributions (where applicable). 

Annual Performance Bonus: For 2023
target pay-outs will be 60% and 
50% per cent. of annual base salary for Craig Tooman (60%) and Giles Campion (50%) with maximum pay-outs of 90% 
and  60%  respectively.  The  Committee  considers  overall  corporate  performance  and  individual  performance  when 
determining the final bonus amount to be awarded to an Executive Director. Performance will be tested against targets 
set  by  the  Committee  at  the  start  of  the  year  and  will  comprise  100%  corporate  goals  for  Craig  Tooman  and  Giles 
Campion

3 corporate objectives are weighted as follows: 

objectives for 2023. 

 Objective 

1      SLN 360 milestone delivery 
2      SLN 124 milestone delivery 
3      SLN 501 milestone delivery 
4      Manufacturing processes 
5     New business development deals 
6      Achievement of financial targets 
7     Candidate selection 
8    Execution/Operations 
       TOTAL 

Weighting   

12 % 
20 % 
8 % 
8 % 
25 % 
17 % 
5 % 
5 % 
100 % 

Specific  targets  are  commercially  sensitive  and  therefore  are  not  disclosed  in  advance.  However,  full  details  of  the 
targets and performance against them will be disclosed when they are no longer considered commercially sensitive. 

Payments for Loss of Office (audited information) 

There was no loss of office payments in 2022. 

James Ede-Golightly 
Chair of the Remuneration Committee  

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SILENCE THERAPEUTICS PLC 

Report 

The Directors present their report and the audited financial statements of the Group for the year ended 31 December 
2022. 

Principal Activities 

The Company has full control and ownership of the following subsidiaries: 

  Silence Therapeutics GmbH 
  Silence Therapeutics (London) Ltd 

Innopeg Ltd 

  Silence Therapeutics Inc. 

The Company, Silence Therapeutics GmbH, Silence Therapeutics (London) Ltd, Innopeg Ltd and Silence Therapeutics 

The principal activity of the Group is focused on the discovery, delivery and development of RNA therapeutics. 

Responsibilities 

The  Directors  are  responsible  for  preparing  the  Annual  Report  and  the  financial  statements  in  accordance  with 
applicable law and regulation. 

Company law requires the directors to prepare financial statements for each financial year. Under that law the directors 
have prepared the group financial statements in accordance with UK-adopted international accounting standards and 
the company financial statements in accordance with United Kingdom Generally Accepted Accounting Practice (United 

Under company law, Directors must not approve the financial statements unless they are satisfied that they give a true 
and fair view of the state of affairs of the group and company and of the profit or loss of the group for that period. In 
preparing the financial statements, the Directors are required to: 

select suitable accounting policies and then apply them consistently; 

state  whether  applicable  UK-adopted  international  accounting  standards  have  been  followed  for  the  group 
financial statements and United Kingdom Accounting Standards, comprising FRS 101 have been followed for 
the company financial statements, subject to any material departures disclosed and explained in the financial 
statements; 

  make judgements and accounting estimates that are reasonable and prudent; and 

  prepare the financial statements on the going concern basis unless it is inappropriate to presume that the Group 

and Company will continue in business. 

The  Directors  are  also  responsible  for  safeguarding  the  assets  of  the  Group  and  Company  and  hence  for  taking 
reasonable steps for the prevention and detection of fraud and other irregularities. 

The  Directors  are  responsible  for  keeping  adequate  accounting  records  that  are  sufficient  to  show  and  explain  the 
transactions and disclose with reasonable accuracy at any time the financial position of the 

and 

Group and Company and enable them to ensure that the financial statements comply with the Companies Act 2006. 

The Directors are responsible for the  maintenance and integrity of the 
website. Legislation in the United 
Kingdom  governing  the  preparation  and  dissemination  of  financial  statements  may  differ  from  legislation  in  other 
jurisdictions. 

55 

 
 
 
 
 
 
 
 
SILENCE THERAPEUTICS PLC 

 confirmations 

In the case of each Director in office at the date the 

report is approved: 

so  far  as  the  Director  is  aware,  there  is  no  relevant  audit  information  of  which  the  Gro
auditors are unaware; and 

and 

they have taken all the steps that they ought to have taken as a Director in order to make themselves aware of 
auditors  are  aware  of  that 
any  relevant  audit  information  and  to  establish  that  the 
information. 

and 

Review of the Business and Future Developments 

The strategic report describes research and development activity during the year as well as outlining future planned 
developments.  Details  of  the  financial  performance,  including  comments  on  the  cash  position  and  research  and 
development expenditure, are given in the financial review. Principal risks and uncertainties are given in the strategic 
report. 

Health, Safety and Environment 

The Directors are committed to ensuring the highest standards of health and safety, both for their employees and for 

environment; see detailed statement in the Corporate Social Responsibility section of the Strategic Report. 
estimated electricity  usage for the reporting  period  is 518,500 kWh (an estimated 224 metric tons of CO2 equivalent 
emissions), with 2.5% of that estimated usage occurring in the United Kingdom. 
premises are located in 
shared facilities so energy consumption is estimated based on space leased.  

Employees 

The Directors are committed to continuing involvement and communication with employees on matters affecting both 
employees and the Group. Management conducts regular meetings with all employees on site. 

Political and charitable contributions 

The Group did not make any political donations or incur any political expenditure during the year (2021: nil). The Group 
made total charitable donations of £75 thousand during the year (2021: £75 thousand). 

Research and Development 

In 2022, the Group spent £35.6 million on research and development (2021: £30.8 million). 

Subsequent Events 

The Group has no subsequent events. 

Financial Risk Management 

A description of financial risk management is set out in note 28 to the financial statements. 

Results and Dividends 

The Group recorded a loss for the year before taxation of £47.4 million (2021: £45.8 million). The loss after tax for the 
year was £40.5 million (2021: £39.4 million). Further details are given in the financial review. The Group is not yet in a 
position to pay a dividend and the loss for both periods has been added to accumulated losses. 

56 

 
 
 
 
 
SILENCE THERAPEUTICS PLC 

Indemnification of Directors 

Qualifying third party indemnity provisions (as defined in the Companies Act 2006) are in force for the benefit of Directors 
and former Directors who held office during 2022 and up to the signing of the annual report. 

Directors 

The Directors who served at any time during the year or since the year end were: 

Director 
Iain Ross 
Craig Tooman (appointed as a Director: 21 February 2022) 

Mark Rothera (resigned as Director: 21 February 2022) 
Giles Campion 
Alistair Gray 
Dave Lemus 
James Ede-Golightly 
Dr. Steven Romano 
Dr. Michael Davidson 

The interests of the Directors in the share 

Substantial Interests 

Job title 
Chairman 
Chief Executive Officer 
Former Chief Executive 
Officer 
Executive Director 
Non-Executive 
Non-Executive 
Non-Executive 
Non-Executive 
Non-Executive 

At 31 December 2022 the Company had been informed of the following substantial interests of over 3% in the issued 
share capital of the Company: 

Shareholder 
Richard Griffiths 
Robert Keith 
Compagnie Odier SCA 
Mallinckrodt plc and affiliated entities 
AstraZeneca UK Limited 
Deep Track Capital LP 
TCG Crossover Management, LLC. 
BVF Partners L.P. 
Aquilo Capital Management, LLC 

Percentage of 
issued share 
capital 

23.9% 
11.3% 
19.7% 
4.7% 
4.1% 
5.4% 
5.9%  
4.2%  
3.6%  

Number of shares   
25,799,271    
12,199,473    
21,281,802    
5,062,167    
4,418,022    
5,854,740    
6,314,625    
4,525,248    
3,852,399    

Material Uncertainty Related to Going Concern 

The accompanying consolidated financial statements have been prepared assuming that the Group will continue as a 
going  concern.  As  discussed  in  Note  2.3  to  the  consolidated  financial  statements,  the  Group  has  incurred  recurring 
losses  and  cash  outflows  from  operations  and  has  stated  that  these  events  or  conditions  indicate  that  a  material 

plans in regard to these matters are also described in Note 2.3. The consolidated financial statements do not include 
any adjustments that might result from the outcome of this uncertainty.

This report was approved by the Board of Directors and signed on its behalf by: 

Craig Tooman  
Chief Executive Officer 
23 March 2023 

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SILENCE THERAPEUTICS PLC 

3 

Financial statements 

 of Silence Therapeutics plc 

Consolidated income statement 

Consolidated statement of comprehensive income 

Consolidated balance sheet 

Consolidated statement of changes in equity 

Company balance sheet 

Company statement of changes in equity 

Cash flow statements 

Notes to the financial statements 

Company information and advisers 

58 

 
 
 
 
   
   
   
 
 
 
 
   
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
SILENCE THERAPEUTICS PLC 

of Silence Therapeutics Plc 

Report on the audit of the financial statements 

Opinion 
In our opinion: 

for the year then ended; 
the group financial statements have been properly prepared in accordance with UK-adopted international accounting standards as applied 
in accordance with the provisions of the Companies Act 2006; 
the  company  financial  statements  have  been  properly  prepared  in  accordance  with  United  Kingdom  Generally  Accepted  Accounting 

 December 

ue and fair 

the financial statements have been prepared in accordance with the requirements of the Companies Act 2006. 

We have audited the financial statements, included within the Annual Report, which comprise: The consolidated and company balance sheets 
as  at  31 December 2022;  the  consolidated  income  statement,  the  consolidated  statement  of  comprehensive  income,  the  consolidated 
statement of cash flows, and the consolidated and company statements of changes in equity for the year then ended; and the notes to the 
financial statements, which include a description of the significant accounting policies. 

Basis for opinion 

under ISAs (UK) are further described in 
that the audit evidence we have obtained is sufficient and appropriate to provide a basis for our opinion. 

onsibilities 

Independence 
We remained independent of the group in accordance with the ethical requirements that are relevant to our audit of the financial statements 
as applicable to listed entities, and we have fulfilled our other ethical responsibilities 

in accordance with these requirements. 

Material uncertainty related to going concern 
In forming our opinion on the financial statements, which is not modified, we have considered the adequacy of the disclosure  made in note 
2 to the group financial statemen
continue as a going concern. The Directors believe that, based on existing cash facilities and on their current forecasts and plans for raising 
additional financing from new and existing investors, the Group and Company will have sufficient funds to meet their cash requirements for 
at least the next 12 months. However, there is no guarantee that attempts to raise adequate additional financing on a timely  basis will be 
successful. These conditions, along with the other matters explained in those notes to the financial statements, indicate the existence of a 
continue  as  a  going  concern.  The 
financial statements do  not  include  the adjustments that  would  result if  the  group and  the  company were  unable  to continue  as   a  going 
concern. 

of the going concern basis of accounting in the preparation of 

the financial statements is appropriate. 

accounting included: 

asis  of 

59 

 
 
 
 
 
 
 
 
SILENCE THERAPEUTICS PLC 

  Testing the mathematical accuracy of the cash flow forecasts. 
  Comparing the current year actual results to cash flow forecasts. 
  Gaining and understanding from management on any notable year-on-year changes in the forecasts, including the assumptions used in 
the  forecasts,  and  obtaining  an  update  on  the  sources  of  funding  options  being  sought,  as  set  out  in  note  2  to  the  group  financial 
statements and note C.2 in the company financial statements and we considered whether there were additional risks that ne eded to be 
reflected in the forecasts. 

  Using our understanding of the group and the company and the industry in which they operate to assess the possibility of additional risk 

arising and their potential impact. 

  Evaluating the disclosures within the financial statements. 

Our responsibilities and the responsibilities of the directors with respect to going concern are described in the relevant sections of this report. 

Our audit approach 

Context 
Silence Therapeutics plc is a public limited company incorporated under the laws of England and Wales and is listed on the NASDAQ. 

Overview 
Audit scope 

  There are 5 reporting units and we identified 2 units which, in our view, required a full scope audit based on their size and risk 
  All  of  the  work  was  performed  by  the  Group  audit  engagement  team  including  the  Group  finance  consolidation,  financial  statement 
disclosures and a number of complex items, prepared by the head office finance function. These included goodwill, current and deferred 
taxes, derivatives, going concern and central adjustments recorded as part of the consolidation process. 

  Taken  together,  the  Group  companies,  as  well  as  the  consolidation  adjustments,  over  which  we  performed  our  audit  procedures 
accounted for 100% of the loss before tax and 100% of revenue. Our audit scope provided sufficient appropriate audit evidence as a 
basis for our opinion on the Group financial statements as a whole. 

Key audit matters 

  Material uncertainty related to going concern (group and parent) 

parent) 

associated accruals and prepayments (group and parent) 

  Carrying value of the investment in Silence Therapeutics GmbH (parent) 

Materiality 

  Overall group materiality: £2,368,000 (2021: £2,089,000) based on 5% of Loss before tax. 
  Overall company materiality: £2,132,000 (2021: £1,754,000) based on 5% of Loss before tax. 
  Performance materiality: £1,776,000 (2021: £1,565,000) (group) and £1,599,000 (2021: £1,315,614) (company). 

The scope of our audit 
As part of designing our audit, we determined materiality and assessed the risks of material misstatement in the financial statements. 

Key audit matters 

the financial 
statements of the current period and include the most significant assessed risks of material misstatement (whether or not due to fraud) 
identified by the auditors, including those which had the greatest effect on: the overall audit strategy; the allocation of resources in the 
audit; and directing the efforts of the engagement team. These matters, and any comments we make on the results of our procedures 
thereon, were addressed in the context of our audit of the financial statements as a whole, and in forming our opinion thereon, and we do 
not provide a separate opinion on these matters. 

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SILENCE THERAPEUTICS PLC 

In  addition  to  going  concern,  described  in  the  Material  uncertainty  related  to  going  concern  section  above,  we  determined  the  matters 
described below to be the key audit matters to be communicated in our report. This is not a complete list of all risks identified by our audit. 

The key audit matters below are consistent with last year. 

Key audit matter 

How our audit addressed the key audit matter 

assessment of revenue recognition under collaboration 
agreements (group and parent) 

The Group has entered into collaboration agreements 
with third parties, who obtain research services and 

patents and know-
The Directors (management) have assessed the 
agreements include a mixture of fixed and variable 
consideration relating to the achievement of future 
milestones. They have previously been assessed to 
determine the separability of performance obligations, 
with the transaction price allocated to performance 
obligations based on their relative standalone selling 
price. The agreements overlap between different 
reporting periods and the timing of invoicing and cash 
receipts does not match with the progress of performance 
obligations. 

At each period end management calculate the revenue 
recognised for the period based on the percentage of 
completion of each performance obligation, by using the 
input method based on cost to cost, whereby 
management determines the proportion of programme 
and personnel costs incurred to date in comparison to the 
total expected costs (both internal and external). Total 
revenue recognised from collaborations during the year 
ended 31 December 2022 is £16.9m (2021: £12.0m). 

(Please see note 3 for further details) 

We performed the following audit procedures to address 
the risk: 
- Leveraged the previous assessment of the collaboration 
contracts and obtained an update from management to 
confirm no changes in this assessment which would impact 
the accounting treatment; 
- Obtained managemen

of both internal costs and costs from third parties (external 
costs); 
- Where applicable, we confirmed that these costs are 
aligned to the collaboration plan and agreed by all parties; 
- 
confirmed these are consistent with approved budgets. We 
further performed a sensitivity analysis over the budgeted 
internal FTE rates ( i.e. Full time employee cost per head) 
to evaluate how changes to the 2023 budget would affect 
the average rates, and ultimately determined whether this 
would have a material impact on revenue. Additionally, on 
a sample basis we tested the underlying inputs ( i.e. 
salaries) of the budgeted payroll costs and recalculated 

budget; 
- 
programme Workplans, by splitting these future costs into 
elements that are already contracted or committed (i.e. 
Non-judgemental) and elements which are based on 

of contingent costs);
- On a sample basis, we matched the committed costs with 
contracts or quotations from the third parties. For the 
estimated costs, we held discussions with relevant project 
managers to challenge and assess the reasonableness of 
these estimates. We also performed a retrospective review 

costs; and 
- Tested the mathematical accuracy of the calculations. 

All of the testing above has been performed to obtain a 
high level of assurance. Other elements of revenue 

non-third party related actual costs 

designated as having a normal risk of material 
misstatement and have been tested to obtain a normal 

related a

assessment of costs related to third party research and 

accruals and prepayments. 

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SILENCE THERAPEUTICS PLC 

contracts including associated accruals and prepayments 
(group and parent) 

There is an inherent risk of error as a result of estimates 
that involve identifying the progress of research projects, 
which considers the progress of external costs and feeds 
into the risk around the estimation of completion for 
revenue over collaboration agreements. 

As the majority of research and development expenditure 
arises from the outsourcing of studies and clinical trials 
tothird-parties, management are required to calculate the 
expense and the associated accruals and prepayments 
based on the progress of the R&D contract versus the 
amounts billed to date at the end of each period. 

and ability to monitor the progression of a piece of 
research, or a trial's stage of completion. As a result, it 
can be difficult for management to measure what costs 
have been incurred in relation to a trial at a specific point 
in time and, as such, based on the billings received, 
whether the project accruals and prepayments recorded 
are appropriately estimated. Our audit risk focuses on 
whether the research projects are being appropriately 
recognised in expenses and whether associated accruals 
and prepayments are being correctly recorded. As at 31 
December 2022, third party R&D contracts totalled £3.8m 
in accruals and £6.7m in prepayments. 

Please see notes 16 and 18 for further details. 

We concluded that m
under collaboration agreements is appropriate. 

We performed the following audit procedures to address 
the risk: 
- Tested a sample of research projects over £100k 
performing the following procedures: 
- 
associated accruals and prepayments positions as at 31 
December 2022, based on progress assessments from 
project managers; 
- Tested the mathematical accuracy of the calculations; 
- Obtained the underlying contracts and understood the 
basis on which the project managers assessed the 
progress, and that management had recognised the costs; 
- Verified the progress of projects by reviewing the support 
available, such as reading the minutes of meetings held 
between Silence and the third parties where the progress 
of the sampled projects was discussed. We confirmed that 
there was no contradictory evidence; 
- Verified that the assessment of progress confirmed by 
internal project managers was consistent with that provided 
by the third parties; and 
- Performed look-back procedures to assess the outcome 
of prior year accruals with no matters noted. 

The testing above has been performed to obtain a 
moderate level of assurance. Other elements of the 
calculations, such as the completeness of accruals and 
prepayments and the completeness of expenses were 
designated as having a normal risk of material 
misstatement and have been tested to obtain a lower level 
of assurance. 

For projects under £100k we tested a sample of invoices to 
a low level of assurance to ensure that the expense was 
accurately recorded and that the accruals or prepayments 
were reasonable. 

research costs through the year and the related accruals 
and prepayments are appropriate. 

Carrying value of the investment in Silence Therapeutics 
GmbH (parent) 

As at 31 December 2022 the parent company held an 
investment in its wholly owned subsidiary Silence 

We performed the following audit procedures to address 
the risk: 

long-term receivable from GmbH of £14.2m. A provision 
of £20.2m had been recorded against the investment 
balance in previous years, resulting in a net investment in 
GmbH of £3.1m, plus the loan balance. 

Management has performed an impairment assessment 
on the net investment in accordance with IAS 36 
(Impairment of assets) and determined that no 
impairment was necessary in the current year. Judgement 
is required in the impairment assessment, specifically in 
forecasting the timing and probability of future contractual 

sensitivity on key assumptions within the model does not 

s impairment analysis and 
gained an understanding of the key assumptions and 
judgements underlying the assessment. We assessed the 
appropriateness of the methodology applied and tested the 
mathematical accuracy of the models, with no exceptions 
identified. We assessed and challenged the key 
assumptions, including the timing and probability of future 
milestones receipts by: 
- Discussing the status of projects with the project 
managers 
- Comparing the expected size and timing of milestone 
payments to the original collaboration agreements; and 

62 

 
 
 
  
 
 
 
 
 
 
  
 
 
SILENCE THERAPEUTICS PLC 

result in a different conclusion, thus no impairment is 
deemed necessary. 

- confirming that the timing of future receipts is consistent 
with our review of board minutes and project status 
meetings. 

Please see note C.6 for further details 

impairment is required in relation to the carrying value of 
the investment and no provision against the loan are 
appropriate. 

How we tailored the audit scope 
We tailored the scope of our audit to ensure that we performed enough work to be able to give an opinion on the financial sta tements as a 
whole, taking into account the structure of the group and the company, the accounting processes and controls, and the industry in which they 
operate. 

ting  entities.  These  functions 
maintain  their  own  accounting  records  and  controls (although  transactional  processing  and  certain controls  for  some  reporting   units  are 
performed by the head office finance team) and report to the head office finance team through an integrated consolidation system. 

In establishing the overall Group audit strategy and plan, we determined all of the work that needed to be performed at the reporting units 
could be performed by the Group engagement team. For each reporting entity we determined whether we required an audit of their reported 
The  two  reporting  entities  where  a  full  scope  audit  was  required  included  Silence  Therapeutics  plc 
(incorporated  in  the  UK)  and  Silence  Therapeutics  GmbH  (incorporated in the  UK) were  determined as individually financially  significant 

In addition to the work performed at the in-scope reporting entities, there is work performed at head office by the Group audit engagement 
team. The Group consolidation, financial statement disclosures and a number of complex items, prepared by the head office finance function, 
were audited by the Group engagement team. These included goodwill, current and deferred taxes, going concern and central adjustments 
recorded as part of the consolidation process. 

Reporting units where audit procedures were performed accounted for 100% of Group revenue and 100% of Group total losses before tax. 
As a result of its structure and size, the Group also has a number of small reporting entities that make up a trivial portion of the key coverage 
metrics. These small reporting units are covered by the work performed by the Group audit engagement team, where we perform  analytical 
review  procedures.  Those  not  subject  to  analytical  review  procedures  were  individually,  and  in  aggregate,  immaterial.  This  ga ve  us  the 
evidence we needed for our opinion on the financial statements as a whole. 

The Company's accounting process is performed by the head office finance team, who maintain the Company's own accounting records and 
controls. 

All of the work is performed at the head office by the group engagement team. This includes the financial statement disclosures and complex 
items, prepared by the head office finance function such as investments and intercompany. 

The impact of climate risk on our audit 
As part of our audit we made enquiries of management to understand the extent of the potential impact of climate risk on the  

and 

f climate 

nancial statements. 

Materiality 
The scope of our audit was influenced by our application of materiality. We set certain quantitative thresholds for materiality. These, together 
with qualitative considerations, helped us to determine the scope of our audit and the nature, timing and extent of our audit procedures on 
the individual financial statement line items and disclosures and in evaluating the effect of misstatements, both individually and in aggregate 
on the financial statements as a whole. 

Based on our professional judgement, we determined materiality for the financial statements as a whole as follows: 

63 

 
 
 
 
 
  
 
SILENCE THERAPEUTICS PLC 

Overall 
materiality 

How we 
determined it 

Rationale for 
benchmark 
applied 

Financial statements - group 

Financial statements - company 

£2,368,000 (2021: £2,089,000). 

£2,132,000 (2021: £1,754,000). 

5% of Loss before tax 

5% of Loss before tax 

The group is loss making, as expected given its 
status as an early stage biotech company which 
has not yet commercialised its products. As such, 
loss before tax is deemed to be the most 
appropriate benchmark on which to calculate 
materiality, as this is the metric on which the 
group's financial performance is assessed. 

The company is loss making, as expected given 
its status as an early stage biotech company 
which has not yet commercialised its products. As 
such, loss before tax is deemed to be the most 
appropriate benchmark on which to calculate 
materiality, as this is the metric on which the 
company's financial performance is assessed. 

For each component in the scope of our group audit, we allocated a materiality that is less than our overall group materiality. The range of 
materiality allocated across components was £1,205,000 to £2,132,000. Certain components were audited to a local statutory audit materiality 
that was also less than our overall group materiality. 

We use performance materiality to reduce to an appropriately low level the probability that the aggregate of uncorrected and  undetected 
misstatements exceeds overall materiality. Specifically, we use performance materiality in determining the scope of our audit and the nature 
and  extent  of  our  testing  of  account  balances,  classes  of  transactions  and  disclosures,  for  example  in  determining  sample  sizes.  Our 
performance materiality was 75% (FY2021: 75%) of overall materiality, amounting to £1,776,000 (2021: £1,565,000) for the group financial 
statements and £1,599,000 (2021: £1,315,614) for the company financial statements. 

In  determining  the  performance  materiality,  we  considered  a  number  of  factors  -  the  history  of  misstatements,  risk  assessment  and 
aggregation risk and the effectiveness of controls - and concluded that an amount at the upper end of our normal range was appropriate. 

We agreed  with  those charged with  governance that  we  would report to them  misstatements identified  during our audit  above £118,000 
(group audit) (2021: £10,000) and £107,000 (company audit) (2021: £87,700) as well as misstatements below those amounts that,  in our 
view, warranted reporting for qualitative reasons. 

Reporting on other information 
The  other  in
thereon. The directors are responsible for the other information. Our opinion on the financial statements does not cover the other information 
and, accordingly, we do not express an audit opinion or, except to the extent otherwise explicitly stated in this report, any form of assurance 
thereon. 

In connection with our audit of the financial statements, our responsibility is to read the other information and, in doing so, consider whether 
the other information is materially inconsistent with the financial statements or our knowledge obtained in the audit, or otherwise appears to 
be materially misstated. If we identify an apparent material inconsistency or material misstatement, we are required to perform procedures 
to conclude whether there is a material misstatement of the financial statements or a material misstatement of the other information. If, based 
on the work we have performed, we conclude that there is a material misstatement of this other information, we are required to report that 
fact. We have nothing to report based on these responsibilities. 

With respect to the Strategic report and Directors' report, we also considered whether the disclosures required by the UK Companies Act 
2006 have been included. 

Based on our work undertaken in the course of the audit, the Companies Act 2006 requires us also to report certain opinions and matters as 
described below. 

Strategic report and Directors' report 
In our opinion, based on the work undertaken in the course of the audit, the information given in the Strategic report and Directors' report for 
the year ended 31 December 2022 is consistent with the financial statements and has been prepared in accordance with applicable legal 
requirements. 

64 

 
 
 
  
  
SILENCE THERAPEUTICS PLC 

In light of the knowledge and understanding of the group and company and their environment obtained in the course of the audit, we did not 
identify any material misstatements in the Strategic report and Directors' report. 

Responsibilities for the financial statements and the audit 

Responsibilities of the directors for the financial statements 
As  explained  more  fully  in  the  statement 
Responsibilities,  the  directors  are  responsible  for  the  preparation  of  the  financial 
statements in accordance with the applicable framework and for being satisfied that they give a true and fair view. The directors are also 
responsible  for  such  internal  control  as  they  determine  is  necessary  to  enable  the  preparation  of  financial  statements  that  are  free  from 
material misstatement, whether due to fraud or error. 

ontinue as a going 
concern, disclosing, as applicable, matters related to going concern and using the going concern basis of accounting unless the directors 
either intend to liquidate the group or the company or to cease operations, or have no realistic alternative but to do so. 

Audito
Our objectives are to obtain reasonable assurance about whether the financial statements as a whole are free from material misstatement, 
 report that includes our opinion. Reasonable assurance is a high level of assurance, 
but  is  not  a  guarantee  that  an  audit  conducted  in  accordance  with  ISAs  (UK)  will  always  detect  a  material  misstatement  when  i t  exists. 
Misstatements can arise from fraud or error and are considered material if, individually or in the aggregate, they could reasonably be expected 
to influence the economic decisions of users taken on the basis of these financial statements. 

Irregularities,  including  fraud,  are  instances  of  non-compliance  with  laws  and  regulations.  We  design  procedures  in  line  with  our 
responsibilities,  outlined  above,  to  detect  material  misstatements  in  respect  of  irregularities,  including  fraud.  The  extent  to  which  our 
procedures are capable of detecting irregularities, including fraud, is detailed below. 

Based on our understanding of the group and industry, we identified that the principal risks of non-compliance with laws and regulations 
related to patent protection, data privacy, product safety and regulatory compliance, and we considered the extent to which non-compliance 
might have a material effect on the financial statements. We also considered those laws and regulations that have a direct impact on the 
financial statements such as the Companies Act 2006
of  the  financial  statements  (including  the  risk  of  override  of  controls),  and  determined  that  the  principal  risks  were  related  to  posting 
inappropriate journal entries to manipulate financial results, misappropriation of cash and potential management bias in accounting estimates. 
Audit procedures performed by the engagement team included: 

  Discussions with management and internal legal counsel including consideration of known or suspected instances of non-compliance 

with laws, regulations and fraud 

  Review of minutes of meeting with the Board of Directors 

Identifying and testing journal entries, in particular any journal entries posted with unusual account combinations and journals posted by 
senior management 

  Challenging assumptions made by management in their significant accounting estimates, in particular in relation to the recognition of 

revenue related to collaboration agreements 

There are inherent limitations in the audit procedures described above. We are less likely to become aware of instances of no n-compliance 
with laws and regulations that are not  closely related to events and transactions reflected in the financial statements. Also, the risk of not 
detecting a material misstatement due to fraud is higher than the risk of not detecting one resulting from error, as fraud may involve deliberate 
concealment by, for example, forgery or intentional misrepresentations, or through collusion. 

Our audit testing might include testing complete populations of certain transactions and balances, possibly using data auditing techniques. 
However, it typically involves selecting a limited number of items for testing, rather than testing complete populations. We will often seek to 
target particular items for testing based on their size or risk characteristics. In other cases, we will use audit sampling to enable us to draw a 
conclusion about the population from which the sample is selected. 

www.frc.org.uk/auditorsresponsibilities. This description 

65 

 
 
 
 
 
 
SILENCE THERAPEUTICS PLC 

Use of this report 

apter 3 of 
Part 16 of the Companies Act 2006 and for no other purpose. We do not, in giving these opinions, accept or assume responsibility for any 
other purpose or to any other person to whom this report is shown or into whose hands it may come save where expressly agreed  by our 
prior consent in writing. 

Other required reporting 

Companies Act 2006 exception reporting 
Under the Companies Act 2006 we are required to report to you if, in our opinion: 

  we have not obtained all the information and explanations we require for our audit; or 
  adequate accounting records have not been kept by the company, or returns adequate for our audit have not been received from branches 

not visited by us; or 

the company financial statements are not in agreement with the accounting records and returns. 

We have no exceptions to report arising from this responsibility. 

Sam Taylor (Senior Statutory Auditor) 

for and on behalf of PricewaterhouseCoopers LLP 

Chartered Accountants and Statutory Auditors 

Reading 

23 March 2023 

66 

 
 
 
 
 
 
  
SILENCE THERAPEUTICS PLC 

Consolidated income statement 
year ended 31 December 2022 

Revenue 
Cost of sales 
Gross profit 
Research and development costs 
Administrative expenses 
Operating loss 
Finance and other expenses 
Finance and other income 
Loss for the year before taxation 
Taxation 
Loss for the year after taxation 

Note      

 3   

 5    
7   
 8    

 9    

2022   
£000s   

17,501  
(10,880 ) 
6,621   
(35,605 ) 
(19,609 ) 
(48,593 ) 
(47 ) 
1,272   
(47,368 ) 
6,879   
(40,489 ) 

2021   
£000s   
12,415   
(7,456 ) 
4,959   
(30,765 ) 
(20,008 ) 
(45,814 ) 
(52 ) 
10   
(45,856 ) 
6,446   
(39,410 ) 

Loss per ordinary equity share (basic and diluted) 

10      (41.9) pence   

   (44.3) pence 

Consolidated statement of comprehensive income 
year ended 31 December 2022 

Loss for the year after taxation 
Other comprehensive expense, net of tax: 
Items that may subsequently be reclassified to profit and 
   loss: 
Foreign exchange differences arising on consolidation of foreign 
   operations 
Total other comprehensive income/(expense) for the year 
Total comprehensive expense for the year 

2022   
£000s   

(40,489 )      

2021   
£000s   
(39,410 ) 

544        
544        
(39,945 )      

(677 ) 
(677 ) 
(40,087 ) 

The accompanying accounting policies and notes form an integral part of these financial statements. 

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SILENCE THERAPEUTICS PLC 

Consolidated balance sheet 
at 31 December 2022 

Non-current assets 
Property, plant and equipment 
Goodwill 
Other intangible assets 
Financial assets at amortised cost 

Current assets 
Cash and cash equivalents 
Financial assets at amortised cost 
R&D tax credit receivable 
Other current assets 
Trade receivables 

Non-current liabilities 
Lease liability 
Contract liabilities 

Current liabilities 
Contract liabilities 
Trade and other payables 
Lease liability 

Net assets 

Note     

31 December 
2022   
£000s   

11       
12       
13       
17       

14       
15       
10       
16       
17       

19      
20       

20       
18       
19       

2,201        
8,009        
320        
284        
10,814        

54,816        
16,328        
14,882        
9,745        
915        
96,686        

(263)      
(63,485 )      
(63,748 )      

(8,864 )      
(12,633 )      
(183 )      
(21,680 )      
22,072        

2021   
£000s   

1,944   
7,592   
24   
301   
9,861   

73,537   
-   
6,945   
5,520   
331   
86,333   

-  
(72,501 ) 
(72,501 ) 

(4,247 ) 
(10,783 ) 
(137 ) 
(15,167 ) 
8,526   

Capital and reserves attributable to the owners of the parent 
Share capital 
Capital reserves 
Translation reserve 
Accumulated losses 
Total shareholders equity 

22                              5,390        
277,860        
24       
2,085        
(263,263 )      
22,072        

4,489   
225,462   
1,541   
(222,966 ) 
8,526   

The financial statements on pages 67 to 100 were approved by the Board on 23 March 2023 and signed on its behalf. 

Craig Tooman 
Chief Executive Officer 

Company number: 02992058 

The accompanying accounting policies and notes form an integral part of these financial statements. 

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SILENCE THERAPEUTICS PLC 

Consolidated statement of changes in equity 
year ended 31 December 2022 

Note   

22     
22     
24 / 22     

24     
24     
24 / 22     

At 31 December 2020 

Recognition of share-based payments 
Options exercised in the year 
Proceeds from shares issued 

Transactions with owners recognised  
   directly in equity 
Loss for year 
Other comprehensive income 
Foreign exchange differences arising on 
   consolidation of foreign operations 
Total comprehensive expense for the year 
At 31 December 2021 

Recognition of share-based payments 
Options exercised in the year 
Proceeds from shares issued 

Transactions with owners recognised  
   directly in equity 
Loss for year 
Other comprehensive income 
Foreign exchange differences arising on 
   consolidation of foreign operations 
Total comprehensive expense for the year 
At 31 December 2022 

Capital 
reserves   
£000s   

Share 
capital   
£000s   
4,165        186,891       
8,632       
(659 )     
30,598       

-       
-       
324       

Translation 
reserve   
£000s   
2,218       
-       
-       
-       

Accumulated 
losses   
£000s   
(184,215 )     
-       
659       
-       

324       
-       

38,571       
-       

-       
-       

659       
(39,410 )     

-       
-       

-       
-       
4,489        225,462       
10,252       
(192 )     
42,338       

-       
-       
901       

(677)       
(677)       
1,541       
-       
-       
-       

-       
(39,410 )     
(222,966 )     
-       
192       
-       

901       
-       

52,398       
-       

-       
-       

192       
(40,489 )     

Total 
equity   
£000s   
9,059   
8,632   
-   
30,922   

39,554   
(39,410 ) 
-   

(677)   
(40,087 ) 
8,526   
10,252   
-   
43,239   

53,491   
(40,489 ) 
-   

-       
-       

-       
-       
5,390        277,860       

544       
544       
2,085       

-       
(40,489 )     
(263,263 )     

544  
(39,945 ) 
22,072   

The accompanying accounting policies and notes form an integral part of these financial statements. 

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SILENCE THERAPEUTICS PLC 

Consolidated statement of cash flows  
year ended 31 December 2022 

Cash flow from operating activities 
Loss before tax 
Depreciation charges 
Amortisation charges 
Charge for the year in respect of share-based payments 
Net foreign exchange (gain)/loss 
Finance and other expenses 
Finance and other income 
(Increase)/decrease in trade and other receivables 
Increase in other current assets 
(Increase) in R&D Tax Credit Receivable 
Decrease in derivative financial instrument 
Increase in trade and other payables 
Increase in contract liabilities 
Cash generated/(spent) on operations 
R&D tax credits received 
Net cash (outflow)/inflow from operating activities 
Cash flow from investing activities 
Redemption of financial assets at amortised cost 
Purchase of financial assets at amortized cost 
Interest received 
Purchase of property, plant and equipment 
Purchase of intangible assets 
Net cash inflow/(outflow) from investing activities 
Cash flow from financing activities 
Repayment of lease liabilities 
Proceeds from issue of share capital 
Net cash inflow from financing activities 
Increase in cash and cash equivalents 
Cash and cash equivalents at start of year 
Effect of exchange rate fluctuations on cash and cash equivalents held 
Cash and cash equivalents at end of year 

 term deposits 

Year ended 31 December 

2022   
£000s   

(47,368 )      
478        
4        
10,252        
713        
-        
(1,272 )      
(584)        
(4,225 )      
(502)    
-    
1,447        
(4,399)        
(45,456)        
-        
(45,456)        

-        

(16,125)    

23        
(140 )      
(300 )      
(16,542)        

(190 )      
43,239        
43,049        
(18,949)        
73,537        
228        
54,816        

The accompanying accounting policies and notes form an integral part of these financial statements. 

2021   
£000s   

(45,856 ) 
411   
16   
8,632   
305   
52   
(10 ) 
27,483  
(904 ) 
-  
1,492  
2,405   
8,369   
2,395  
4,411   
6,806  

10,000   
-  
10   
(1,311 ) 
(23 ) 
8,676   

(211 ) 
30,922   
30,711   
46,193   
27,449   
(105 ) 
73,537   

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SILENCE THERAPEUTICS PLC 

Notes to the consolidated financial statements 
year ended 31 December 2022 

1. 

General information 

1.1 

Group 

development of RNA therapeutics. Silence Therapeutics plc, a public Company limited by shares registered in England 
and Wales, with company number 02992058
is 27 Eastcastle Street, London, W1W 8DH and the principal place of business is 72 Hammersmith Road, London, W14 
8TH. 

2. 

Principal accounting policies 

2.1 

Basis of preparation 

The  consolidated  financial  statements have  been  prepared  in  accordance with  international accounting  standards  in 
conformity with the requirements of the Companies Act 2006, as applicable to companies using IFRS. The consolidated 
financial statements have been prepared under the historical cost convention as modified by revaluation to fair value of 
the derivative financial instrument. The accounting policies set out below have, unless otherwise stated, been prepared 
consistently for all periods presented in these consolidated financial statements. The financial statements are prepared 
in sterling and presented to the nearest thousand pounds.  

New standards and interpretations not yet adopted 

Certain new accounting standards and interpretations have been published that are not mandatory for  31 December 
2022 reporting periods and have not been early adopted by the Group. These include amendments to IAS1 'Presentation 
of financial statements' on classification of liabilities. These standards are not expected to have a material impact on the 
entity in the current or future reporting periods and on foreseeable future transactions. 

2.2 

Basis of consolidation 

The  Consolidated  financial  statements  consolidate  those  of  the  Company  and  its  controlled  subsidiary  undertakings 
drawn up to 31 December 2022. The Group controls an entity when the Group is expected to, or has rights to, variable 
returns from its involvement with the entity and has the ability to affect those returns through its power over the entity. 
Where necessary, adjustments are made to the financial statements of subsidiaries to bring accounting policies into line 
with those used for reporting the operations of the Group. All intra Group transactions, balances, income and expenses 
are eliminated on consolidation. 

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SILENCE THERAPEUTICS PLC 

2.3 

Going concern 

The  Group  has  incurred  recurring  losses  since  inception,  including  net  losses  of  £40.5  million  for  the  year  ended 
December 31, 2022. As of December 31, 2022, the Group had accumulated losses of £263.3 million and cash outflows 
from operating activities for the year ended 31 December 2022 of £45.5 million. The Group expects to incur operating 
losses  for  the  foreseeable  future  as  it  continues  its  research  and  development  efforts,  seeks  to  obtain  regulatory 
approval of its product candidates and pursues any future product candidates the Group may develop. 

To-date, the Group has funded its operations through upfront payments and milestones from collaboration agreements, 
equity offerings and proceeds from private placements, as well as management of expenses and other financing options 
to support its continued operations. 

During 2021, the Group received $40.0 million (£30.8 million) of the upfront payments in respect of the AstraZeneca 
collaboration, $45 million from a private placement of ADSs (approximately $42.0 million / £30.8 million, net of expenses) 
and approximately $16.0 million (£10.7 million) of the upfront payment, (net of taxes withheld, based on the exchange 
rate  at  the payment  date),  related  to  the  Hansoh  Pharmaceutical  Group  Company  Limited  or  Hansoh,  collaboration 
executed on October 14, 2021. In August 2022 the Group raised additional funds through a registered direct offering 
with  aggregate  gross  proceeds  of  $56.5  million  (approximately  £46.4  million)  before  deducting  $4.1  million 
(approximately £3.3 million) in underwriting discounts, commissions and estimated offering expenses. As of December 
31, 2022, the Group had cash and cash equivalents and U.S. Treasury Bills of £71.1 million ($86.0 million). 

The Group has the responsibility to evaluate whether conditions and/or events raise material uncertainty about its ability 
to meet its future financial obligations as they become due within one year after the date that the financial statements 
are  issued.  The  forecast  for  evaluating  the  going  concern  basis  of  the  Group  includes  continued  investment  in  our 
technology platform and product pipeline. The forecast does not include collaboration milestones which have not been 
fully achieved or other assumptions for potential future non-dilutive or dilutive funding sources. Based on this evaluation, 
the Group believes that its current cash and cash equivalents are only sufficient to fund its operating expenses through 
the first quarter of 2024. This indicates that a material uncertainty exists that may cast sign
ability to continue as a going concern and therefore the Group may be unable to realize assets and discharge liabilities 
in the normal course of business. 

The Group will need to raise additional funding to fund its operation expenses and capital expenditure requirements in 
relation to its clinical development activities. The Group may seek additional funding through public or private financings, 
debt financing or collaboration agreements. Specifically, the Group may receive future milestone payments of up to $14 
million  from  existing collaboration agreements  in  the  next 12  months  which will  extend  the  ability to fund  operations 
beyond the first quarter of 2024. However, these future milestone payments are dependent on achievement of certain 
development or regulatory objectives that may not occur. The Group has an authorized open market sale agreement 
and can potentially raise funds through the sale of ADSs. However, there is no assurance that we will be successful in 
obtaining sufficient funding on terms acceptable to us, or if at all. The inability to obtain future funding could impact; the 

eliminate some of its research and development programs, or being unable to continue operations or unable to continue 
as a going concern.  

These consolidated financial statements have been prepared assuming that the Group will continue as a going concern 
which contemplates the continuity of operations, realization of assets and the satisfaction of liabilities in the ordinary 
course of business and do not include adjustments that would result if the Group were unable to continue as a going 
concern. 

2.4 

Research and development 

The  Group  recognise  expenditure  incurred  in  carrying  out  its  research  and  development  activities  in  line  with 

the calculation of research and development accruals at each period to account for expenditure that has been incurred. 
This requires estimations of the full costs to complete each study or activity and also estimation of the current stage of 
completion. In all cases, the full cost of each study or activity is expensed by the time the final report or, where applicable, 
product, has been received. Further details on research and development can be found in note 2.11. 

72 

 
 
 
SILENCE THERAPEUTICS PLC 

2.5 

Revenue recognition 

agreements. 

Royalty income 

 December 2022 consists of royalty income and revenue from collaboration 

Alnylam is obliged to pay royalties to the Group on the net sales of ONPATTRO  in the EU in a manner commensurate 
with the contractual terms. Invoices are raised in arrears on a quarterly basis based on sales information provided by 
Alnylam no later than 75 days after the quarter end.  

The  royalty  exemption  under IFRS 15 requires sales-based data. Royalty  revenue is  recognised  when sales data  is 
received, based on the level of sales when the related sales occur. 

Revenue from collaboration agreements 

We  have considered  the  Mallinckrodt, AstraZeneca, and Hansoh contracts and  assessed whether the research and 
development services and license of the IP in respect of each target are distinct. 

For all contracts we have concluded the license of the intellectual property and the R&D services are not distinct, as 
Mallinckrodt, AstraZeneca, and Hansoh cannot benefit from the intellectual property absent the R&D services, as those 
R&D services are used to discover and develop a drug candidate and to enhance the value in the underlying intellectual 
property, and these services could not be performed by another party, indicating that the two are highly interrelated. On 
this basis, we have concluded that there  is a single performance obligation covering both the R&D services and the 
license of the intellectual property in respect of each target. We recognise revenue over the duration of the contract 
based on an input method based on cost to cost. 

The contracts have multiple elements of consideration (some or all of the following), namely: 

  Upfront payments (fixed); 

Subsequent milestone payments (variable); 

FTE costs rechargeable (variable); 

  Recharges of direct costs for certain research activities (variable). 

The 
over the contract period based on costs to completion. 

continues throughout their entire duration. On this basis revenue is recognised 

Revenue has been calculated on the following ongoing basis for the year ended 31 December 2022: 

Total contract costs which includes actual FTE and direct costs incurred up to 31 December 2022 and forecast 
FTE and direct costs for the remainder of the contract 

Actual costs incurred up until 31 December 2022 are calculated as a percentage of total contract costs (actual 
and forecast) 

This percentage is then multiplied by the transaction price allocated to the performance obligation in question, 
thus calculating the cumulative revenue which is then used to calculate the revenue to be recognised in that 
period. In the case of the upfront and milestones, the consideration that is multiplied is in relation to the upfront 
and completed milestones only. Consideration in relation to milestones not yet achieved is excluded from the 
calculation.   

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SILENCE THERAPEUTICS PLC 

Forecast costs are monitored each period, with revenue recognised reflecting any changes in forecast or over/under 
spend in actuals. 

Further details of the revenue amounts recognised in the year ended 31 December 2022 can be found in note 3. 

2.6 

Foreign currency translation 

The consolidated financial statements are presented in sterling. The individual financial statements of each Group entity 
are prepared in the currency of the primary economic environment in which the entity operates (its functional currency). 

al 
currency (foreign currencies) are recorded at the rates of exchange prevailing on the dates of the transactions. At each 
balance sheet date, monetary items denominated in foreign currencies are retranslated at the rates prevailing on the 
balance sheet date. 

Exchange  differences  arising  on  the  settlement  of  monetary  items,  and  on  the  retranslation  of  monetary  items,  are 
included in the income statement for the year.  

operations (including comparatives) are translated into sterling using exchange rates prevailing on the balance sheet 
date. Income and expense items (including comparatives) are translated at the  average exchange rates for the year 
unless individually significant to the Group at which point they are translated at spot rate. Exchange differences arising, 
if any, are recognised in equity. 

2.7 

Defined contribution pension funds 

The contributions payable to defined contribution retirement schemes are recognised as an expense in the period to 
which they relate. On the payment of the contribution the Group has no further liability. 

2.8 

Business combinations 

There were no new business combinations as defined by IFRS 3 during 2021 or 2022. 

All  goodwill  is  attributed  to  an  acquisition  that  occurred  in  2005.  Goodwill  represents  the  excess  of  the  cost  of  the 
recognised amount (generally fair value) of the identifiable assets, liabilities 

and contingent liabilities of the acquiree. 

2.9 

Property, plant and equipment 

The Group holds no property assets other than leased property assets classified as right-of-use assets. See note 2.14 
for further details. 

All equipment and furniture is stated in the financial statements at its cost of acquisition less a provision for 
depreciation. 

Depreciation is charged to write off the cost less estimated residual values of furniture and equipment on a straight-
line basis over their estimated useful lives. All equipment and furniture is estimated to have a useful economic life of 
between three and ten years. Estimated useful economic lives and residual values are reviewed each year and 
amended if necessary. 

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SILENCE THERAPEUTICS PLC 

2.10  Goodwill 

Goodwill is stated at cost less any accumulated impairment losses; it is allocated to the cash generating unit or operating 
segment that is expected to benefit from synergies of the related business combination and represent the lowest level 
within  the  Group  at  which  management  controls  the  related  cash  flows.  Goodwill  is  not  amortised  but  is  tested  for 
impairment annually, or sooner when an indication of impairment has been identified. Goodwill arising on the acquisition 

identifiable  assets,  liabilities  and  contingent  liabilities  of  the  subsidiary  at  the  date  of  acquisition.  On  disposal  of  a 
subsidiary, the attributable amount of goodwill is included in the determination of the profit or loss on disposal. 

2.11  Other intangible assets 

Other  intangible  assets  that  are  acquired  by  the  Group  are  stated  at  cost  less  accumulated  amortisation  and  less 
accumulated impairment losses. 

Amortisation 

Amortisation is charged to the income statement on a straight-line basis over the estimated useful lives of intangible 
assets unless such lives are indefinite. Intangible assets with an indefinite useful life and goodwill are systematically 
tested for impairment at each balance sheet date. Other intangible assets are amortised from the date they are available 
for use. The estimated useful lives are as follows: 

Licences and software  10 

 15 years. 

Capitalisation of research and development costs 

Costs associated with research activities are treated as an expense in the period in which they are incurred. 

Costs that are directly attributable to the development phase of an internal project will only be recognised as intangible 
assets provided they meet the following requirements: 

  an asset is created that can be separately identified; 

the technical feasibility exists to complete the intangible asset so that it will be available for sale or use and the 
Group has the intention and ability to do so; 

it is probable that the asset created will generate future economic benefits either through internal use or sale;  

sufficient technical, financial and other resources are available for completion of the asset; and 

the expenditure attributable to the intangible asset during its development can be reliably measured. 

Careful judgment by management is applied when deciding whether recognition requirements for development costs 
have been met. This is necessary as the economic success of any product development is uncertain and may be subject 
to  future  technical  problems  at  the  time  of  recognition.  Judgements  are  based  on  the  information  available  at  each 
balance sheet date. 

To date, no development costs have been capitalised in respect of the internal projects on the grounds that the costs to 
date are either for the research phase of the projects or, if relating to the development phase, then the work so far does 
not meet the recognition criteria set out above. In most cases recognition would not occur until regulatory approval. 

2.12 

Impairment testing of goodwill, other intangible assets and property, plant and equipment 

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SILENCE THERAPEUTICS PLC 

At each balance sheet date non-financial assets are assessed to determine whether there is an indication that the asset 
At least annually or if there is such an indication, the recoverable 

amount of the 

value in use. 

Impairment losses recognised for cash generating units to which goodwill has been allocated are credited initially to the 
carrying amount of goodwill. Any remaining impairment loss is charged pro rata to the other assets in the cash generating 
unit. 

2.13 

Financial instruments 

Financial assets and financial liabilities are recognised on the balance sheet when the Group becomes a party to the 
contractual provisions of the instrument. 

For  the  periods  presented  in  these  financial  statements,  financial  assets  were  classified  in  the  following categories: 
derivative financial instruments, and financial assets at amortised cost. Currently other categories of financial asset are 
not used. Management determines the classification of its financial assets at initial recognition. 

The de-recognition of financial instruments occurs when the rights to receive cash flows from investments expire or are 
transferred and substantially all of the risks and rewards of ownership have been transferred. 

Derivative financial instruments  

The  Group uses forward contracts to  manage  exposure to risks from foreign exchange  movements. Derivatives  are 
initially  recognised  at  fair  value  at  the  date  that  the  contract  is  entered  into  and  subsequently  remeasured  at  each 
balance sheet date. The resulting gain or loss is recognised in the income statement. 

Financial assets at amortised cost 

Financial assets at amortised cost include trade receivables held in order to collect contractual cash flows, U.S. Treasury 
Bills, and a term deposit held to collect solely payment of the principal and interest, and deposits on property operating 
leases and for the procurement of materials. These are measured at initial recognition at fair value plus, if appropriate, 
directly  attributable  transaction  costs  and  are  subsequently  measured  at  amortised  cost  using  the  effective  interest 
method, less provision for impairment. Premiums and discounts, if any, are amortised or accreted as interest expense 
or income over the life of the related asset using the effective interest method. Any impairment is assessed using the 
Expected Credit Losses (ECL) model. The Group applies the IFRS 9 simplified approach to measuring expected credit 
losses which uses a lifetime expected loss allowance for trade receivables. Any impairment is recognised in the income 
statement. 

Cash and cash equivalents 

Cash and cash equivalents comprise cash on hand and demand deposits with original maturities of three months or 
less that are readily convertible to a known amount of cash and are subject to an insignificant risk of change in value. 

Financial liabilities and equity 

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SILENCE THERAPEUTICS PLC 

Financial  liabilities  and  equity  instruments  issued  are  classified  according  to  the  substance  of  the  contractual 
arrangements entered into and the definitions of a  financial liability  and an equity instrument. A financial  liability is a 
contractual obligation to either deliver cash or another financial asset to another entity or to exchange a financial asset 
or financial liability with another entity, including obligations which may be settled using its equity instruments. An equity 
instrument  is  any  contract  that  evidences  a  residual  interest  in  the  assets  after  deducting  all  of  its  liabilities.  The 
accounting policies adopted for specific financial liabilities and equity instruments are set out below. 

Financial liabilities 

At initial recognition, financial liabilities are measured at their fair value minus, if appropriate, any transaction costs that 
are directly attributable to the issue of the financial liability. After initial recognition, all financial liabilities are measured 
at amortised cost using the effective interest method. 

Equity instruments 

Equity instruments issued by the Group are recorded as the proceeds received, net of direct issue costs. 

2.14 

 Leased assets 

For any new contracts entered into on or after 1 January 2019, the Group considers whether a contract is, or contains 

asset)  for  a  per
contract meets two key evaluations, which are whether: 

the contract contains an identifiable asset;  

the  Group  has  the  right  to  obtain  substantially  all  of  the  economic  benefits  from  use  of  the  identified  asset 
throughout the period of use 

Measurement and recognition 

At lease commencement date, the Group recognises a right-of-use asset (as part of the appropriate underlying class of 
assets in property, plant and equipment) and a lease liability on the balance sheet.  

The  right-of-use asset  is measured  at cost comprising  the  following: the  amount  of the initial  measurement  of lease 
liability, any lease payments made at or before the commencement date less any lease incentives received, any initial 
direct costs, and restoration costs. The Group depreciates the right-of-use assets on a straight-line basis from the lease 
commencement date to the earlier of the end of the useful life of the right-of-use asset or the end of the lease term. The 
Group also assesses the right-of-use asset for impairment when such indicators exist. 

At the commencement date, the Group measures the lease liability at the present value of the lease payments unpaid 
at that date, discounted u
of the lease liability are made up of fixed payments (including in substance fixed), variable payments based on an index 
or  rate,  amounts  expected  to  be  payable  under  a  residual  value  guarantee  and  payments  arising  from  options 
reasonably certain to be exercised. Subsequent to initial measurement, the liability will be reduced for payments made 
and increased for interest.  

The Group has elected to account for short-term leases (leases with a duration of less than 12 months) and leases of 
low-value  assets  using  the  practical  expedients.  Instead  of  recognising  a  right-of-use  asset  and  lease  liability,  the 
payments in relation to these are recognised as an expense in profit or loss on a straight-line basis over the lease term. 

The interest payments for leases are recognised in the statement of cashflows under finance and other expenses. 

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SILENCE THERAPEUTICS PLC 

Lease break clauses and extension options 

When the Group has the option to extend a lease, management uses its judgment to determine whether or not an option 
would be reasonably certain to be exercised. Management considers all facts and circumstances including past practice 
and any cost that will be incurred to change the asset if an option to extend is not taken, to help determine the lease 
term. 

Similarly, when a break clause exists in the lease agreement, management must consider the likelihood of this option 
to curtail the lease being exercised. 

2.15 

Share-based payments 

Historically  the  Group  has  issued  equity  settled  share-based  payments  to  certain  employees  (see  note  25).  Equity 
settled share-based payments are measured at fair value (excluding the effect of non-market-based vesting conditions) 
at the date of grant. The fair value so determined is expensed on a straight-line basis over the vesting period, based on 
the Group of the number  of  shares that will  eventually vest and  adjusted  for  the effect of  non-market-based vesting 
conditions.  

The value of the charge is adjusted to reflect expected and actual levels of award vesting, except where failure to vest 
is as a result of not meeting a market condition.  

Cancellations of equity instruments are treated as an acceleration of the vesting period and any outstanding charge is 
reversed in full immediately.  

Fair value is measured using a Black Scholes model, binomial pricing model or Monte Carlo model. The key assumptions 
estimate,  for  the  effects of non-transferability, 

exercise restrictions and behavioural considerations.  

Any  payment made  to a counterparty on  the cancellation or settlement  of  a grant  of equity instruments (even  if  this 
occurs after the vesting date) should be accounted for as a repurchase of an equity interest (that is, as a deduction from 
equity). But, if the payment exceeds the fair value of the equity instruments repurchased (measured at the repurchase 
date), any such excess should be recognised as an expense. 

2.16 

Equity 

Share capital is determined using the nominal value of shares that have been issued. 

The share premium account includes any premiums received on the initial issuing of the share capital. Any transaction 
costs associated with the issuing of shares are deducted from the share premium account, net of any related income 
tax benefits. 

The merger reserve represents the difference between the nominal value and the market value at the date of issue of 
shares issued in connection with the acquisition by the Group of an interest in over 90% of the share capital of another 
company. 

Equity settled share-based payments are credited to a share-based payment reserve as a component of equity until 
related options or warrants are exercised. 

Foreign currency translation differences are included in the translation reserve. 

Profit and loss account (deficit) includes all current and prior period results as disclosed in the income statement. 

78 

 
 
 
 
 
SILENCE THERAPEUTICS PLC 

2.17 

Taxation 

Current tax payable is based on taxable profit for the year. Taxable profit differs from profit as reported in the income 
statement because it excludes items of income or expense that are taxable or deductible in other years and it further 
excludes items that are never taxable or deductible. Current tax liabilities are calculated using tax rates that have been 
enacted or substantively enacted by the balance sheet date. 

Tax receivable arises from the U.K. legislation regarding the treatment of certain qualifying research and development 
costs,  allowing  for  the  surrender  of  tax  losses  attributable  to  such  costs  in  return  for  a  tax  rebate.  Research  and 
development tax credits are recognised when the receipt is probable. 

Deferred  tax  is  recognised  on  differences  between  the  carrying  amounts  of  assets  and  liabilities  in  the  financial 
statements and the corresponding tax bases used in the computation of taxable profit and is accounted for using the 
balance sheet liability method. Deferred tax liabilities are generally recognised for all taxable temporary differences and 
deferred tax assets are recognised to the extent that it is probable that taxable profits will be available against which 
deductible temporary differences can be utilised. 

Such assets and liabilities are not recognised if the temporary difference arises from initial recognition of goodwill or 
from  the  initial  recognition  (other  than  in  a business  combination)  of  other  assets  and  liabilities  in  a transaction  that 
affects neither the taxable profit nor the accounting profit. 

Deferred tax liabilities are recognised for taxable temporary differences arising on investments in subsidiaries except 
where the Group is able to control the reversal of the temporary difference and it is probable that the temporary difference 
will not reverse in the foreseeable future. 

The carrying amount of deferred tax assets is reviewed at each balance sheet date and reduced to the extent that it is 
no longer probable that sufficient taxable profits will be available to allow all or part of the asset to be recovered. 

Deferred tax is calculated at the tax rates that are expected to apply in the period when the liability is settled, or the 
asset realised. Deferred tax is charged or credited to the income statement, except when it relates to items charged or 
credited directly to equity, in which case the deferred tax is also dealt with in equity. 

Deferred tax assets and liabilities are offset when there is a legally enforceable right to set off current tax assets against 
current tax liabilities and when they relate to income taxes levied by the same taxation authority and the Group intends 
to settle its current tax assets and liabilities on a net basis. 

Withholding tax is payable on gross income from dividends, interest, lease of property, royalties, and other China-source 
passive income since the Group does not have an establishment or place of business in China. 

2.18  Critical accounting estimates and judgements and key sources of estimation uncertainty 

effect on the amounts recognised 
best knowledge of current events and actions, actual results may ultimately differ from those estimates. 

The critical judgments concerning the future, and other key sources of estimation uncertainty at the balance sheet date, 
that have a significant risk of causing a material adjustment to the carrying amounts of assets and liabilities within the 
next financial year, are described below: 

Application of IFRS 15 in determining revenue from contracts with customers specifically: 

79 

 
 
 
 
 
SILENCE THERAPEUTICS PLC 

o 

o 

The  determination  of  the  numbers  of  performance  obligations.  Judgement  was  previously  required  in 
determining whether the license and the R&D activities are distinct performance obligations or not at the 
time  the  collaboration  agreements  were  executed.  It  is  considered  the  license  of  the  IP  and  the  R&D 
activities are not distinct as the R&D services are essential to discover and develop a drug candidate and 
enhance the value in the underlying IP. In addition, the gene targets are highly specialised such that only 
the Group has the specialist knowledge to apply the IP to the specific target. On this basis, it was concluded 
that there is only one single performance obligation covering both the R&D services and licenses of the IP 
in respect of each target at the time the agreements were executed; 

The  allocation of the upfront payments between performance obligations (judgement). Mallinckrodt paid 
the Group $20 million in 2019, AstraZeneca have paid the Group $60 million in 2020 and 2021, and Hansoh 
paid  $16  million  upfront  under  their  respective  contracts,  which  is  in  2021.  A  judgment  was  required  to 
determine how this should be allocated across the contracted targets. In 2019, due to the compounds being 
at similar stages of development at the time of contract execution, the $20 million paid by Mallinckrodt was 
allocated  evenly,  on  the  basis  of  a benchmarking  exercise considering  the  standalone  selling price  per 
target of past deals announced to the market by comparable companies; similarly it was concluded that the 
$60 million amount to be paid by AstraZeneca was allocated evenly across target options for AstraZeneca.  
The Hansoh $16 million upfront payment was allocated $4 million for each of the two targets in Greater 
China,  Hong  Kong,  Macau and Taiwan and $8  million for  the  global  target based on the benchmarking 
exercise,  as  well  as  consideration  for  geography  licensed  and  other  contractual  terms.  These  initial 
transaction  amounts  are  recognized  as  revenue  over  the  life  of  the  performance  obligations  for  each 
contract. 

The estimate of future costs to be incurred to determine percentage of completion of revenue contracts: 

o 

In determining the percentage of completion of the revenue projects, the Group estimated the total future 
costs expected to be incurred through the life of the performance obligations per the contract. An increase 
in future costs could arise as a result of a requested change in scope by the collaboration partner or through 
higher than anticipated internal costs incurred by Silence. The impact of a change in scope would be largely 
neutral on revenue recognition because there would be consequential increases in revenue to match the 
additional costs. There is no experience of internal costs being higher than anticipated to date, but if this 
were the case then a 10% increase in future estimated costs would lead to a 0.4% increase in revenue. 

2.19 

Segment reporting 

Operating segments are reported in a manner consistent with the internal reporting provided to the Board. The chief 
operating  decision  maker  (CODM),  who  is  responsible  for  allocating  resources  and  assessing  performance  of  the 
operating  segments,  has  been  i
Chief  Executive  Officer.  The  Group has  a  single  reportable 
segment (see note 4). 

3. 

Revenue 

Revenue from collaboration agreements for the year ended 31 December 2022 relates to the Research collaboration 
agreements the Group entered into with Mallinckrodt plc in July 2019, AstraZeneca plc in March 2020, and Hansoh in 
October 2021. 

Revenue  comprised  £0.6  million  of  royalty  income  (2021:  £0.4  million)  and  £16.9  million  of  Research  collaboration 
income (2021: £12.0 million). Disaggregation of Revenue from Contracts with Customers is as follows: 

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SILENCE THERAPEUTICS PLC 

Revenue from Contracts with Customers 

Research collaboration - Mallinckrodt plc 
Research collaboration - AstraZeneca 
Research collaboration 
Research collaboration 
Royalties 

 Other 
 total 

Total revenue from contracts with customers 

2022   
£000s   
11,658        
5,081     
184     
16,923        
578        
17,501        

2021   
£000s   
8,748   
2,652   
623   
12,023   
392   
12,415   

Under our collaboration agreement with Mallinckrodt, we received an upfront cash payment of £16.4 million ($20 million) 
in 2019 and are eligible to receive specified development, regulatory and commercial milestone payments. We received 
milestone payments totalling £2.2 million or $3 million (2021: £2.9 million) during the year ended 31 December 2022. In 
addition  to  these  payments,  Mallinckrodt  has  agreed  to  fund  some  of  our  research  personnel  and  preclinical 
development costs. We recognise the upfront payment, milestone payments, payments for personnel costs and other 
research funding payments over time, in accordance with IFRS 15 para 35 c). During the year ended  31  December 
2022, we recognised a total of £11.7 million in revenue under this agreement. (2021: £8.7 million) 

Under our collaboration agreement with AstraZeneca, we received an upfront cash payment of £17.1 million ($20 million) 
in 2020 with a further amount of £30.8 million ($40 million) received in May 2021. We are also eligible to receive specified 
development and  commercial milestone  payments as  well as tiered royalties on  net sales,  if  any. We  recognise the 
upfront payment and milestone payments over time, in accordance with IFRS 15 para 35 c). During the year ended 31 
December 2022, we recognised a total of £5.1 million in revenue under this agreement. (2021: £2.7 million) 

We entered into a collaboration agreement with Hansoh on 15 October 2021. We received a $16 million (equivalent to 
approximately £11.9 million based on the exchange rate at the payment date and $14.4 million or £10.7 million, net of 
taxes) upfront payment to us in December 2021. We are eligible to receive development, regulatory and commercial 
milestones as well as royalties on Hansoh net product sales. During the year ended December 31, 2022, the Company 
triggered  milestone payments totaling $2.0 million (£1.5 million) (2021: £nil). We recognize the upfront payment and 
milestone payments over time, in accordance with IFRS 15 para 35 c). During the year ended December 31, 2022, we 
recognized a total of £0.2 million in revenue under this agreement to date. (2021: £32 thousand) 

In December 2018, we entered into a settlement and license agreement with Alnylam Pharmaceuticals Inc., or Alnylam, 
pursuant to which we settled outstanding patent litigation with Alnylam related to its RNAi product ONPATTRO.  As part 
of the settlement, we license specified patents to Alnylam, and Alnylam pays us a tiered royalty of up to one percent of 
net sales of ONPATTRO in the European Union. We are eligible to receive these royalties through December 2023. We 
invoice Alnylam quarterly in arrears based on sales data for that quarter as reported to us by Alnylam. Royalty revenue 
is recognised based on the level of sales when the related sales occur. During the year ended 31 December 2022, we 
recognised a total of £0.6 million in royalty income from Alnylam. (2021: £0.4 million) 

4. 

Segment reporting 

In 2022, the Group operated in the specific technology field of RNA therapeutics. 

Business segments 

The Group has identified the Chief Executive Officer as the CODM. For the 12 months ended 31 December 2021 and 
2022, the CODM determined that the Group had one business segment, the development of RNAi-based medicines. 
This is in line with reporting to senior management. The information used internally by the CODM is the same as that 
disclosed in the financial statements. 

81 

 
 
 
  
  
 
  
 
     
     
     
     
     
     
 
 
SILENCE THERAPEUTICS PLC 

An analysis of the G

 assets and revenues by location is shown below: 

Non-current assets 

As at 31 December 2021 
As at 31 December 2022 

Revenue analysis for the year ended 31 December 2021 

Research collaboration 
Royalties 

Revenue analysis for the year ended 31 December 2022 

Research collaboration 
Royalties 

. 

5. 

Operating loss 

This is stated after charging/(crediting): 

U.S.A.     
£000s     

U.K.   
£000s   

Germany   
£000s   

17        
-        

516        
1,166        

9,328        
9,648        

Total   
£000s   

9,861   
10,814   

-        
-        
-        

-        
-        
-        

12,023        
-        
12,023        

-        
392        
392        

12,023   
392   
12,415   

16,923        
-        
16,923        

-        
578        
578        

16,923   
578   
17,501   

Depreciation of property, plant and equipment 
Amortisation of intangibles 
Share-based payments charge 
Short lease payments on premises 
Fees payable to the Company's auditors for the audit of the Company and the consolidation: 
 - audit fees 
 - other assurance services 

6. 

Directors and staff costs 

Wages and salaries 
Social security costs 
Other pension costs 
Share-based payments charge 
Total aggregate remuneration 

2022   
£000s   

478        
4        
10,252        
410        

463        
150        

2021   
£000s   
411   
16   
8,632   
332   

403   
180   

follows: 

2022   
£000s   
14,760        
1,434        
429        
10,252        
26,875        

2021   
£000s   
10,837   
1,491   
319   
8,632   
21,279   

Remuneration and share based payments detail for all Directors is presented in the Remuneration Committee report. 
See page 37 for further details. 

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SILENCE THERAPEUTICS PLC 

Research and development and related support services 
Administration 
Total average number of employees 

7. 

Finance and other expenses 

Lease liability interest expense 
Net foreign exchange losses 
Total Finance and other expenses 

8. 

Finance and other income 

Bank interest receivable 
Accreditation on U.S. Treasury Bills 
Net foreign exchange gains 
Total Finance and other income 

9. 

Taxation 

2022   
Number   

88        
28        
116        

2021   
Number   
66   
26   
92   

2022   
£000s   

47        
-        
47        

2022   
£000s   

23        

203    
1,046    
1,272        

2021   
£000s   
8   
44   
52   

2021   
£000s   
10   
-  
-  
10   

The entire tax credit of £6.9m relates to current tax as shown below. No deferred tax was recognised in the year. 

The deferred tax charge in 2022 was nil (2021: nil). Reconciliation of tax credit at standard rate of U.K. corporation tax 
to the current tax credit: 

Loss before tax 
Tax credit at the standard rate of U.K. corporation tax of 19% (2021: 19%; 2020: 
19%) 
Effect of overseas tax rate 
Impact of unrelieved tax losses not recognised  
Adjustment in respect of prior year 
Research and development tax credit in respect of current year 
Effect of overseas taxes 

2022   
£000s   
(47,368 )      

9,000         
544        
(9,948 )      
  (401)         
7,836         
(152 )      
6,879         

2021   
£000s   
(45,856 )   

8,713     
(264 )   
(8,639 )   
875     
6,945     
(1,184)     
6,446     

Estimated tax losses of £167.8 million (2021: £154.1 million) are available for relief against future profits. 

83 

 
 
 
  
  
 
  
  
 
     
     
     
 
 
 
  
  
 
  
  
 
     
     
     
 
 
  
  
 
  
  
 
     
 
 
 
 
 
 
     
 
 
  
  
  
  
 
 
  
  
 
 
     
     
     
     
     
     
     
  
     
 
SILENCE THERAPEUTICS PLC 

The deferred tax asset not recognised in these financial statements on the estimated losses and the treatment of the 
equity settled share- based payments, net of any other temporary timing differences is detailed in note 23. During the 
year, the Group  had not yet received a research and development tax credit of related to the prior year (2021: £4.4 
million). The Group has accrued £7.8 million (2021: £6.95 million) recognising a current tax asset in respect of 2022 
research and development tax credits. The company had a foreign tax expense of £0.4 million. (2021: £0.2 million). 

The corporation tax main rate during 2022 was 19%  (2021: 19%). In the Spring Budget 2021, the U.K. Government 
announced that from 1 April 2023 the corporation tax rate will increase to 25%. As the company has not recognised and 
related deferred tax assets as at 31 December 2022, the tax rate increase has no impact. 

Since the Group does not have an establishment or place of business in China, the Group is subject to withholding tax 
on  gross  income from  dividends, interest,  lease  of  property,  royalties,  and  other  China-source  passive  income.  The 
Group entered into a collaboration agreement with Hansoh, a biopharmaceutical company in China and received a $16 
million upfront payment, which required withholding tax of $1.6 million. In 2022 the Group received a milestone payment 
of £1.5 million ($2.0 million), which required withholding tax of £0.2 million. 

10. 

Loss per ordinary equity share (basic and diluted) 

The calculation of the loss per share is based on the loss for the financial year after taxation of £40.5 million (2021: loss 
of £39.4 million) and on  the weighted  average of 96,584,512 (2021: 88,950,441) ordinary shares in  issue during the 
year. 

The options outstanding at 31 December 2021 and 31 December 2022 are considered to be anti-dilutive as the Group 
is loss-making. 

84 

 
 
 
 
 
SILENCE THERAPEUTICS PLC 

11 

Property, plant and equipment 

Cost 

At 1 January 2021 

Additions 
Disposals 
Translation adjustment 

At 31 December 2021 
At 1 January 2022 

Additions 
Disposals 
Translation adjustment 

At 31 December 2022 

Accumulated depreciation 

At 1 January 2021 

Charge for the year 
Eliminated on disposal 
Translation adjustment 

At 31 December 2021 
At 1 January 2022 

Charge for the year 
Eliminated on disposal 
Translation adjustment 

At 31 December 2022 

Net book value 

As at 31 December 2021 
As at 31 December 2022 

12.  Goodwill 

Balance at start of year 
Translation adjustment 
Balance at end of year 

Equipment and 
furniture   
£000s   

Right-of-use 
asset   
£000s   

4,066        
1,311        
(46)        
(219)        
5,112        
5,112        
140        
(506 )      
240        
4,986        

3,274   

238        
(46 )      
(173)        
3,293        
3,293   

306        
(506 )      
144        
3,237        

1,819        
1,749        

456   
-   
(111 ) 
-   
345   
345   
499   
(346 ) 
-   
498   

121   
173   
(74 ) 
-   
220   
220   
172   
(346 ) 
-   
46   

125   
452   

Total   
£000s   

4,522   
1,311   
(157 ) 
(219 )  
5,457   
5,457   
639   
(852 ) 
240  
5,484   

3,395   
411   
(120 ) 
(173)   
3,513   
3,513   
478   
(852 ) 
144  
3,283   

1,944   
2,201   

2022   
£000s   
7,592        
417        
8,009        

2021   
£000s   
8,125   
(533)  
7,592   

The recoverable amount is based on fair value less cost of disposal. 

The key assumptions used in the valuation models to determine the fair value less cost of disposal are as follows: 

Fair  value  has  been  determined  as  market  capitalisation  (share  price  x  number  of  shares  in  issue)  at  31 
December 2022 

Disposal costs have been estimated to be minimal 

Goodwill is assessed at a segment level. As there is only one operating segment, we have considered the fair value of 
the entire business as market capitalisation at 31 December 2022, which was £453.3 million (2021: £528.8 million), with 
share price not dropping significantly below its 31 December 2022 value at any point so far in 2023, and therefore a 
sensitivity analysis has not been presented.  

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SILENCE THERAPEUTICS PLC 

13.  Other intangible assets 

Cost 

At 1 January 2021 

Additions 
Translation adjustment 

At 31 December 2021 
At 1 January 2022 

Additions 
Translation adjustment 

At 31 December 2022 

Accumulated depreciation 

At 1 January 2021 

Charge for the year 
Translation adjustment 

At 31 December 2021 
At 1 January 2022 

Charge for the year 
Translation adjustment 

At 31 December 2022 

Net book value 

As at 31 December 2021 
As at 31 December 2022 

Licenses & 
software   
£000s   

107   
23   
-   
130   
130   
300   
-   
430   

90   
16   
-   
106   
106   
4   
-   
110   

24   
320   

The intangible assets included above have finite useful lives estimated to be of 10 15 years from the date of acquisition, 
over which period they are amortised or written down if they are considered to be impaired. Internally generated patent 
costs are only recorded where they are expected to lead directly to near-term revenues, none have been capitalised to 
date. 

14.  Cash and cash equivalents 

Cash at bank and in hand 
U.S. Treasury Bills 
Short term bank deposits 
Total Cash and cash equivalents 

2022   
£000s   
41,986        
12,376    

454        
                          54,816        

2021   
£000s   
73,537   
-  
-   
73,537   

Cash at bank comprises balances held by the Group in current, U.S. Treasury Bills and short-term bank deposits with 
an original maturity of three months or less. The carrying amount of these assets approximates to their fair value. 

15. 

Financial assets at amortised cost 

Non-current financial assets at amortized cost primarily relate to deposits for properties. 

Current financial assets at amortized cost, other than trade receivables as disclosed in note 17, include U.S. Treasury 
Bills (with maturities from purchase date over three months) of £16.3 million (2021: nil). 

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SILENCE THERAPEUTICS PLC 

Financial assets at amortised cost   U.S. Treasury Bills 
Total current financial assets at amortised cost 
Non-current financial assets at amortised cost 
Total financial assets at amortised cost 

16.  Other current assets 

Prepayments 
VAT receivable 
Total other current assets 

2022   
£000s   
16,328        
16,328    

284        
16,612        

2022   
£000s   
8,200        
1,545        
9,745        

2021   
£000s   
-   
-  
301   
301   

2021   
£000s   
4,309   
1,211   
5,520   

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SILENCE THERAPEUTICS PLC 

17. 

Trade receivables 

Trade receivables 

2022   
£000s   

915        

2021   
£000s   
331   

The Directors consider that the carrying amount of trade receivables approximates to their fair value. 
No interest is charged on outstanding receivables. There were no overdue trade receivables balances. 
The Group has applied an expected credit loss model to the balance and determined that £nil (2021: £nil) provision is 
required. 

18. 

Trade and other payables 

Trade payables 
Social security and other taxes 
Accruals and other payables 
Corporate income tax payable 
Total trade and other payables 

2022   
£000s   
3,186        
467        

8,391    

589        
12,633        

2021   
£000s   
4,065   
318   
6,215  
185   
10,783   

The Directors consider that the carrying amount of trade and other payables approximates to their fair value. 

19. 

Lease liability 

Lease liability   current 
Lease liability   non-current 
Total lease liability 

2022   
£000s   

183        
263    
446        

2021   
£000s   
137   
-  
137   

The  lease  liability  recognis
office,  which  was 
renegotiated upon completion of the original term, with the new term beginning in September 2022. The repayment of 
the  principal  portion  of  these  lease  liabilities  for  the  year-ending  December  31,  2022,  was  £0.2  million  (2021:  £0.2 
million). 

There are 2 short-term leases in Berlin, Germany and three leases in Hoboken, U.S., not included in the lease liability 
above. Both leases in Berlin are on a rolling contract basis with either party being able to end the lease with a cancellation 
notice period of 11.5 months, while the leases in the U.S. are on a rolling contract basis with a notice period of three 
months, thus allowing exemption using the practical expedient, without significant cost. 

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SILENCE THERAPEUTICS PLC 

20.  Contract liabilities 

Contract  liabilities  comprise  entirely  deferred  revenue  in  respect  of  the  Mallinckrodt,  AstraZeneca  plc,  and  Hansoh 
research collaborations. The current contract liabilities represent the amount of estimated revenue to be reported in the 
next 12 months related to amounts invoiced to our partners. Current and non-current contract liabilities include future 
revenue from collaboration recharged expenses, upfront payments, and milestones achieved to December 31, 2022 

Contract liabilities: 

Current 
Non-current 

Total contract liabilities 

Contract liabilities: 
At 1 January 2021 

Additions during period 
Revenue unwound during period 

At 31 December 2021 

At 1 January 2022 

Additions during period 
Revenue unwound during period 

At 31 December 2022 

21.  Deferred tax 

2021  
£000s  

4,247  
72,501  
76,748  

31 December, 
2022   
£000s   

8,864        
63,485        
72,349        

Total       

£000s     

68,379         
20,392        
(12,023 )      
76,748     

76,748        
12,519        
(16,918 )       
72,349     

The Group has the following unrecognised deferred tax assets as at 31 December 2022: 

Trading losses 
Share based payments 
Capital losses 

Total unrecognised deferred tax asset 

2022  

2021 

Gross 

 £000s 
  167,828 
   8,995 
  7,873 
  184,696 

Net 
  £000s 
 44,136  
 2,249 
  1,968 
  48,353     176,558 

 Gross 
 £000s 
 152,060 
 16,625 
 7,873 

Net 

£000s 
33,909 
3,159 
1,496 

38,564 

To total unrecognised deferred tax assets are calculated based on the main corporate tax rate of 25% (19% for 2021) 
as this is the rate applicable to when we expect to utilise these deferred tax assets. Unrecognised deferred tax assets 
from foreign trading losses are calculated at the tax rate applicable to the related jurisdiction. 

Deferred tax assets are recognised where it is probable that future taxable profit will be available to utilise losses. Due 
to  the  uncertainty  of future  capital  gains,  a  deferred  tax  asset in  respect  of  capital  losses  was  not  recognised  at  31 
December 2022 (2021: nil). 

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SILENCE THERAPEUTICS PLC 

22. 

Share capital 

Authorised, allotted, called up and fully paid ordinary shares, par value £0.05 

Number of shares in issue 

2022   
£000s   
5,390   

2021   
£000s   
4,489   

Number   
107,808,472   

Number   
89,784,720   

The  Group  has  only  one  class  of  share.  All  ordinary  shares  have  equal  voting  rights  and  rank  pari  passu  for  the 
distribution of dividends. 

Depositary 
  $22.50  per  ADS,  with  new  and  existing 

was US $45 million (approximately £33 million) before deducting approximately £2.4 million in placement agent fees 
and other expenses. The financing syndicate included Adage Capital Management LP, BVF Partners L.P., Consonance 
Capital, Great Point Partners, LLC, and other investors.  

On  October  15,  2021,  the  Company  filed  a  registration  statement  on  Form  F-3  with  the  SEC  to  cover  the  offering, 
issuance and sale of securities from time to time in one or more offerings of up to $300,000,000 in aggregate, which 
includes a sale of up to $100,000,000 of ADSs that may be issued and sold under an Open Market Sale Agreement, 
dated October, 15, 2021, with Jefferies LLC. 

On November 30, 2021, the Company completed delisting from AIM.  As a result, the Company converted the existing 
employee share options to ADSs which represents three ordinary shares and the exercise price was also converted to 
represent  an  ADS  price  at  an  exchange  rate  equal  to  the  average  of  the  last  five  business  trading  days  currency 
conversion of sterling pounds to US dollars, which was 1.334058 sterling pounds to 1 US dollar. This is not a modification 
of the existing share option grants, as the value or timing of the grants was unchanged.  

On August 11, 2022, the Group announced a registered direct offering (t
ADSs, each representing three  ordinary shares, at a price of $9.50  per ADS,  with new and existing institutional and 
accredited  investors.  The  aggregate  gross  proceeds  of  the  Offering  was  $56.5  million  (approximately  £46.4  million) 
before deducting $4.1 million (approximately £3.3 million) in underwriting discounts, commissions and estimated offering 
expenses. 

Details of the shares issued during the current and previous year are as follows: 

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SILENCE THERAPEUTICS PLC 

Number of shares in issue at 1 January 2021 

Shares issued during the year 
Options exercised at £0.05 
Options exercised at £0.85 
Options exercised at £1.00 
Options exercised at £1.28 
Options exercised at £1.90 

Number of shares in issue at 31 December 2021 

Shares issued during the year 
Options exercised at $0.20/ADS or $0.07/ordinary share 
Options exercised at $4.16/ADS or $1.39/ordinary share 
Options exercised at $5.12/ADS or $1.72/ordinary share 
Options exercised at $5.88/ADS or $1.96/ordinary share 
Options exercised at $7.32/ADS or $2.44/ordinary share 
Options exercised at $7.60/ADS or $2.53/ordinary share 

Number of shares in issue at 31 December 2022 
Number of equivalent ADS in issue at 31 December 2022 

83,306,259   
6,066,654   
66,114   
121,854   
25,000   
720  
198,119   
89,784,720   
17,850,000   
84,835   
16,968   
12,951   
24,000  
15,000  
19,998   
107,808,472   
35,936,157  

At 31 December 2022, there were options outstanding over 11,571,487 (2021: 8,052,699) unissued ordinary shares. 

Details of the options outstanding are as follows: 

Year of issue   

Weighted average 
Exercise price (£)    

Weighted average 
Exercise price ($) 

At 1 January  
2022   

Options 
granted   

Options 
forfeited     

Options 
expired   

Options 
exercised   

At 31 
December, 
2022   

Weighted average 
years to expiry date   

2014     

2015     

2016     

2017     

2018     

2019     

3.50 

3.50 

4.25 

6.00 

0.18 

4.31 

2020     

2021     

18.38 

17.33 

2022    

18.44 

Total     

4.23 

4.23 

5.14 

7.25 

0.21 

5.21 

22.22 

20.95 

22.30 

4,000       

3,333       

19,832       

46,240       

70,233       

    763,260       

    1,040,023       

    737,312       

-       

-       

-       

-       

-       

-       

-       

-       

                     -  

-  

(9,973)  

(8,000)  

        (14,876)   

4,000       

3,333  

9,859       

38,240       

55,357       

(12,666 )     

        (25,068)  

725,526       

(316,573 )     

(36,839 )     

-   

-   

723,450       

700,473       

1.67 

2.52 

3.35 

4.83 

5.22 

6.73 

7.58 

8.27 

-  

   1,940,377  

(343,453 )    

-  

   1,596,924  

9.28 

        2,684,233      1,940,377       

(709,531)       

        (57,917)   

3,857,162       

          Number of equivalent ADS 

      8,052,699      5,821,131  

   (2,128,593)     

(173,752)  

   11,571,487      

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SILENCE THERAPEUTICS PLC 

ADSs  represent  three  ordinary  shares  and  the  exercise  price  was  also  converted  to  represent  an  ADS  price  at  an 
exchange  rate  equal  to  the  closing  current  year  currency  conversion  of  sterling  pounds  to  US  dollars,  which  was 
1.208971 sterling pounds to 1 US Dollar. 

The market price of Company shares at the year-end was $15.25/ADS or ($5.08 or 420 pence/share). (2021: 
$23.89/ADS ($7.96 or 590 pence/share); 2020: 514 pence). During the year the minimum and maximum prices were 
$7.80 and $24.66 per ADS (215 pence and 680 pence per ordinary share), respectively (2021: 443 pence and 680 
pence; 2020: 304 pence and 515 pence). 

23. 

Equity-settled share-based payments 

The Group has issued share options under the 2018 Long Term Incentive Plan (LTIP), 2018 Non-Employee Long Term 
Inventive Plan (Non-Employee LTIP), and individual share option contracts, open to all employees of the Group, as well 
as  EMI  shares  (none  of  which  remain  outstanding  at  31  December  2022).  Under  the  LTIP,  Non-Employee  LTIP, 
individual contracts and schemes available, the options typically vest after 3 years, with the exception of some options 
granted to certain members of key management personnel. The vesting period for these options ranges from 3 to 33 
months. The options usually lapse after one year following the employee leaving the Group. 

2022 

Number 
of 
ADSs    
000s    

Weighted 
Average 
Exercise 
price   
$   

Weighted 
Average 
Exercise 
price 
 Pence 

    2,684,233      
    1,940,377      
     (709,531 )    
(57,917 )    
0      
   3,857,162     
    1,889,460      

7.32   
22.30   
29.25   
3.20   
0   
15.10  
13.24   

      605.63 
   1,844.41 
   2,419.76 
      265.05 
       0 
 1,248.95 
 1,095.01 

Options 
Outstanding at the beginning of the year 

Granted during the year 
Lapsed or forfeited during the year 
Exercised during the year 

Outstanding at the year-end (ordinary shares/pence) 
Outstanding at the year-end (ADS/$) 
Exercisable at the year-end 

2021 

Weighted 
Average 
Exercise 
price  
Pence  

Number 
of shares    
000s     

6,768,894        226.83  
2,259,153        554.60  
(563,541 )      146.02  
(411,807 )      116.62  
8,052,699        329.74  
7.32  
2,684,233      
2,503,504        263.45   

The  table  above  shows  the  number  of  options  in  relation  to  ordinary  shares  and  equivalent  ADSs  outstanding  and 
exercisable at year end, on the conversion ratio of three ordinary share options to one ADS as disclosed in Note 24. 

The  options outstanding at the year-end  have a weighted average remaining contractual life of 8.2 years  (2021: 8.3 
years). The weighted average share price at the time of exercise during the year was 318.31 pence per ordinary share 
or $10.91 per ADS (2021: 575 pence). 

The Group granted 5,465,478 ADS options during the year (2021: 2,259,153). The fair value of options granted were 
calculated  using  Black  Scholes  model  for  2022.  Prior  to  January  1,  2022,  the  fair  value  of  options  granted  were 
calculated using a Binomial or Monte Carlo model. Inputs into the model were as follows: 

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SILENCE THERAPEUTICS PLC 

Inputs and assumptions for options granted in the year 
Weighted average share price (pence) 
Weighted average ADS price ($) 
Weight average hurdle price (pence) 
Weighted average exercise price (pence) 
Weighted average ADS price ($) 
Option life (years) 
Expected volatility 
Risk free rate 
Expected dividend yield 

2022   

537.4        
19.5    

2021   

586.0   

n/a                                n/a   
520.0   

673.8        
24.4    

8.9        

56%-74%     
1.16%-3.57%     
nil     

10.0   
65%-70%   
0.28%-1.04%   
nil   

The Group recognised total charges of £10.3 million (2021: £8,6 million) related to equity settled share-based payment 
transactions during the year. 

Fair value of the grants has been calculated using volatility assumptions between 56% and 74%, based on the three 
year historical volatility as at the respective date of grant. 

The Group does not bear any responsibility to settle any employee tax obligations that arise on the exercise of share 
options. The estimated employer tax obligation on outstanding options at the year-end was £0.4 million (2021: £0.6 
million). 

24.  Capital reserves  

The capital redemption reserve was created in 2012 following the reduction of nominal share capital to 0.1p per share. 
It is required under Section 733 of the Companies Act 2006, held to maintain the capital of the Company when shares 
are bought back and subsequently cancelled without court approval. 

Due to the size of the deficit on the accumulated losses account, the Company has no distributable reserves. 

The share premium account reflects the premium to nominal value paid on issuing shares less costs related to the issue. 
The merger reserve was created on issuance of shares relating to the acquisition of Silence Therapeutics GmbH. 

The  share-based  payments  reserve  reflects  the  cost  to  issue  share-based  compensation,  primarily  employee  share 
options. 

At 1 January 2021 
Shares issued 
On options in issue during the year 
On options exercised during the year 
Costs capitalised in respect of issuance of shares during the 
period. 
Movement in the year 
At 31 December 2021 
Shares issued 
On options in issue during the year 
On options exercised during the year 
Costs capitalised in respect of issuance of shares during the 
period. 
Movement in the year 
At 31 December 2022 

Capital
redemption

Merger 
reserve   
£000s   
22,248        
-        
-        
-        

Share-based 
Payment 
reserve   
£000s   
5,715        
-        
8,632        
(659 )      

Share 
Premium 
account   
£000s   
153,734        
32,585        
-        
460        

(2,447)      
30,598        
184,332        
45,533        
-        
153        

-      
-        
22,248        
-        
-        
-        

-      
7,973        
13,688        
-        
10,252        
(192 )      

 -    
10,060        
23,748        

(3,348)      
42,338        
226,670        

-      
-        
22,248        

reserve  
£000s  
5,194       
-       
-       
-       

-    
-       
5,194       
-       
-       
-       

Total   
£000s   
186,891   
32,585   
8,632   
(199 ) 

(2,447)  
38,571   
225,462   
45,533   
10,252   
(39 ) 

-     
-       
5,194       

(3,348)  
52,398   
277,860   

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SILENCE THERAPEUTICS PLC 

25.  Capital commitments and contingent liabilities 

There were no capital commitments at 31 December 2022 (2021: nil). 

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SILENCE THERAPEUTICS PLC 

26.  Commitments under short leases 

At 31 December 2022, the Group had a gross commitment on its office rental and service charge in Berlin, Germany 
and the Hoboken, U.S. lease equal to £0.3 million (2021: £0.3 million) in the next year. No amounts are payable after 
more than one year. 

In addition, the Group enters into contracts in the normal course of business with contract research organisations to 
assist  in  the  performance  of  research  and  development  activities  and  other  services  and  products  for  operating 
purposes. These contracts generally provide for termination on notice, and therefore are cancellable contracts and not 
reflected in the disclosure above. 

27. 

Financial instruments and risk management 

receivables and trade payables which arise directly from its operations. The main purpose of these financial instruments 

approval  is  required  for  adoption  of  any  new  financial  instrument  or  counterparty.  The  primary  focus  of the  treasury 
function is preservation of capital. 

The Directors consider that the carrying amount of these financial instruments approximates to their fair value. 

Financial assets by category 

The categories of financial assets included in the balance sheet and the heading in which they are included are as 
follows. The measurement of financial assets is at amortised cost unless otherwise stated: 

Trade receivables 
Cash and cash equivalents 
Other current assets at amortised cost 
Non-current financial assets at amortised cost 

Financial liabilities by category 

Trade and other payables 
Lease liability 

All amounts are short-term. 

2022   
£000s   

915        
54,816        
16,328        
284        
72,343        

2021   
£000s   
331   
73,537   
-   
301   
74,169   

2022   
£000s   
12,166        
446        
12,612        

2021   
£000s   
10,464   
137   
10,601   

95 

 
 
 
 
 
 
  
  
 
  
  
 
     
     
     
     
  
     
 
 
  
  
 
  
  
 
     
     
  
     
 
 
SILENCE THERAPEUTICS PLC 

Credit quality of financial assets (loans and receivables)  

The maximum exposure to credit risk at the reporting date by class of financial asset was: 

Trade receivables 
Financial assets at amortised cost   non-current 
Financial assets at amortised cost   current 

2022   
£000s   
915   
284  
16,328        
17,527        

2021   
£000s   
331   
301  
-   
632   

Cash and cash equivalents and U.S. Treasury Bills are not considered to be exposed to significant credit risk due to the 
the 

event of non-performance by a financial counterparty to be unlikely. 

The Group regularly monitors the creditworthiness of its customers and at the reporting date, no financial assets are 
credit impaired. 

Capital management 

The Group considers its capital to be equal to the sum of its total equity. The Group monitors its capital using a number 
of measures including cash flow projections, working capital ratios, the cost to achieve pre-clinical and clinical milestones 
and pote
its  capital  is  to  ensure  it  obtains  sufficient  funding  for  continuing  as  a  going  concern.  The  Group  funds  its  capital 
requirements through the issue of new shares to investors, milestone and research support payments received from 
existing licensing partners and potential new licenses. 

Interest rate risk 

ificant liquid resources. 
The Group uses these resources to meet the cost of future research and development activities. Consequently, it seeks 
to minimize risk in the holding  of its bank deposits while maintaining a reasonable rate of interest. The Group  is  not 
financially dependent on the income earned on these resources and therefore the risk of interest rate fluctuations is not 
significant to the business. Nonetheless, the Directors take steps to secure rates of interest which generate a return for 
the Group. 

Credit and liquidity risk 

Credit risk is managed on a Group basis. Funds are deposited with financial institutions with a credit rating equivalent 
o the timing of 

(between zero and three months) and the Group maintains adequate bank balances in either instant access or short-
term deposits to meet those liabilities as they fall due.  

The  Group  only  enters  into  collaboration  agreements  with  large,  reputable  companies  and  the  creditworthiness  of 
customers is monitored on an ongoing basis.  

96 

 
 
 
 
  
  
 
  
  
 
     
 
 
 
 
     
  
     
 
 
 
 
 
SILENCE THERAPEUTICS PLC 

The Group applies the IFRS 9 simplified approach to measuring expected credit losses which uses a lifetime expected 
loss allowance for all trade receivables. Expected loss rates are based on payment profiles of past receivables and the 
aging profiles of outstanding balances at the reporting period end date. The historical loss rates are adjusted to reflect 
current  and  forward-looking  information  on  macroeconomic  factors  affecting  the  ability  of  the  customer  to  settle  the 
receivables. At the year-end there were no debts that were past due or are expected to be past due. It was therefore 
concluded on this basis that there were no expected credit losses for the trade receivable.  

Trade  receivables  are  written  off  where  there  is  no  reasonable  expectation  of  recovery.  Indicators  that  there  is  no 
reasonable expectation of recovery includes, but is not limited to, a failure to engage in a repayment plan with the Group. 

Currency risk 

The Group operates in a global market with revenue possibly arising in a number of different currencies, principally in 
US dollars, sterling or euros. The majority of the operating costs are incurred in euros with the rest predominantly in 
sterling. Additionally, to a lesser extent, a number of operating costs are incurred in US dollars. The Group makes use 
of forward contracts to reduce its exposure to foreign currency risk where the existence, timing and quantum of future 
cash inflows can be accurately predicted. 

Financial assets and liabilities denominated in euros and translated into sterling at the closing rate were: 

Financial assets 
Financial liabilities 
Net financial assets/(liabilities) 

2022   
£000s   
2,302        
(1,279 )      
1,023        

Financial assets and liabilities denominated in US dollars and translated into sterling at the closing rate were: 

Financial assets 
Financial liabilities 
Net financial assets/(liabilities) 

2022   
£000s   
53,086        
(2,947 )      
50,139        

2021   
£000s   
1,918   
(3,278 ) 
(1,360 ) 

2021   
£000s   
11,248   
(876 ) 
10,372   

The following table illustrates the sensitivity of the net result for the year and the reported financial assets of the Group 
in regard to the exchange rate for sterling against the euro. 

During the year sterling rose by 1% (2021: 4%) against the euro. The table shows the impact of an additional weakening 
or strengthening of sterling against the euro by 20%. 

2022 
Group result for the year 
Euro denominated net financial liabilities 
Total equity at 31 December 2022 

As reported   
£000s   

If sterling   
rose 20%   
£000s   

(40,489 )      
1,023        
22,072        

(37,572 )      
853        
21,902        

If sterling   
fell 20%   
£000s   

(44,865 ) 
1,279  
22,328   

97 

 
 
 
 
 
  
  
 
  
  
 
     
     
     
 
 
  
  
 
  
  
 
     
     
     
 
 
  
     
   
 
 
  
  
 
 
  
  
 
 
       
         
         
  
     
     
     
 
SILENCE THERAPEUTICS PLC 

2021 
Group result for the year 
Euro denominated net financial liabilities 
Total equity at 31 December 2021 

(39,410 )      
(1,360 )      
8,526        

(35,618 )      
(1,133 )      
8,753        

(45,099 ) 
(1,700 ) 
8,186   

98 

 
 
 
       
         
         
  
     
     
     
SILENCE THERAPEUTICS PLC 

The following table illustrates the sensitivity of the net result for the year and the reported financial assets of the Group 
in regard to the exchange rate for sterling against the U.S. dollar. 

During the year sterling rose by 10% (2021: 7%) against the US dollar. The table shows the impact of an additional 
weakening or strengthening of sterling against the US dollar by 20%. 

2022 
Group result for the year 
U.S. dollar denominated net financial assets 
Total equity at 31 December 2022 

2021 
Group result for the year 
U.S. dollar denominated net financial assets 
Total equity at 31 December 2021 

28.  Notes to the cash flow statement 

Changes in liabilities arising from financing activities 

Lease liabilities 
Total liabilities from financing activities 

29.  Related party transactions 

As reported   
£000s   

If sterling   
rose 20%   
£000s   

(40,489 )      
50,139        
22,072        

(37,013 )      
41,783        
13,716        

If sterling   
fell 20%   
£000s   

(45,703 ) 
62,674   
34,607   

(39,410 )      
10,372        
8,526        

(36,308 )      
8,643        
6,797        

(44,063 ) 
12,965   
11,119   

Cash flows from 
financing 
activities   

1 January   

2022   
£000s   

137        
137        

Repayments   
£000s   
(190 ) 
(190 ) 

  Non-cash flows   
New lease 
liabilities   
£000s   

499        
499        

31 
December   

2022   
£000s   
446   
446   

We have engaged in the following transactions with our directors, executive officers or holders of more than 10% of our 
outstanding share capital and their affiliates, which we refer to as our related parties. 

In  2022,  we  paid  Gladstone  Consultancy  Partnership,  a  company  controlled  by  our  Non-Executive  Chairman,  £60 
thousand for consulting and advisory services to be provided by Iain Ross (2021:nil). The amounts payable were settled 
before the relevant year ends. 

Key  management  are  considered  to  be  Directors  of  the  Group. 
Remuneration Committee Report.  

  compensation  is  discussed  in  the 

30.   Post Balance Sheet Events 

There were no post balance sheet events as of the filing date.  

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SILENCE THERAPEUTICS PLC 

31.  Group companies 

In accordance with Section 409 of the Companies Act 2006, a full list of subsidiaries, the address of the registered 
offices and effective percentages of equity owned as at 31 December 2022 are disclosed below. 
All subsidiaries are wholly owned. 

Name 
Silence Therapeutics GmbH 

Silence Therapeutics (London) Ltd 
Innopeg Ltd 
Silence Therapeutics Inc. 

Name 
Silence Therapeutics GmbH 
Silence Therapeutics (London) Ltd 
Innopeg Ltd 
Silence Therapeutics Inc. 

Registered office address 

Place of 
incorporation 
and operation  

Principal 
technology 
area 

Proportion of 
ownership 
interest 

 Robert-Rössle-Strasse 10, 13125 Berlin, Germany   
 27 Eastcastle Street, London, W1W 8DH 
 27 Eastcastle Street, London, W1W 8DH 
0c/o Harvard Business Services Inc., 16192 
Coastal Hwy, Lewes, DE 19958 

RNA 

Germany  
England  
England  

therapeutics    
Dormant    
Dormant    

RNA 

100 % 
100 % 
100 % 

USA  

therapeutics    

100 % 

Exempt from 
audit 

Exempt from 
filing financial 
statements 

Yes   
Yes   
Yes   
Yes   

No 
No 
No 
No 

100 

 
 
 
 
 
 
 
  
 
 
 
 
 
  
  
  
  
  
  
 
SILENCE THERAPEUTICS PLC 

Company balance sheet 
at 31 December 2022 

Non-current assets 
Property, plant and equipment 
Other intangible assets 
Investment in subsidiaries 
Financial assets at amortised cost 

Current assets 
Cash and cash equivalents 
Derivative financial instrument 
Financial assets at amortised cost   term deposit 
R&D tax credit receivable 
Other current assets 
Trade and other receivables 

Non-current liabilities 
Lease liability 
Contract liabilities 

Current liabilities 
Contract liabilities 
Trade and other payables 
Lease liability 

Total assets less liabilities 
Net assets 

Share capital 
Capital reserves 
Accumulated losses 
Total equity 

Note   

C.5      
C.5      
C.6      
C.8      

C.7      

C.8      

C.9      
C.10      

C.12  
C.13      

C.13      
C.11      
C.12      

C.14      

2022   
£000s   

563   
320   
17,519   
284   
18,686   

54,067   
-   
16,328   
14,882   
9,505   
934   
95,716   

(263)  
(63,485 ) 
(63,748 ) 

(8,864 ) 
(20,113 ) 
(183 ) 
(29,160 ) 
21,494   
21,494   

2021   
£000s   

208   
24   
16,387   
284   
16,903   

73,272   
-   
-   
6,945   
5,214   
843   
86,274   

-  
(72,501 ) 
(72,501 ) 

(4,247 ) 
(14,960 ) 
(112 ) 
(19,319 ) 
11,357   
11,357   

5,390   
277,676   
(261,572 ) 
21,494   

4,489   
225,278   
(218,410 ) 
11,357   

The Company made a loss of £43.4 million in the year ended 31 December 2022 (2021: £42.3 million). 

The financial statements on pages 101 to 113 were approved by the Board on 23 March 2023 and signed on its 
behalf. 

Craig Tooman 
Chief Executive Officer 

Company number: 02992058 

The accompanying accounting policies and notes form an integral part of these financial statements. 

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SILENCE THERAPEUTICS PLC 

Company statement of changes in equity 
year ended 31 December 2022 

At 1 January 2021 

Recognition of share-based payments 
Options exercised in the year 
Proceeds from shares issued 
Transactions with owners recognised directly in equity 
Loss for the year 
At 31 December 2021 

Recognition of share-based payments 
Options exercised in the year 
Proceeds from shares issued 
Transactions with owners recognised directly in equity 
Loss for the financial year 

At 31 December 2022 

Note   

C.14      
C.14      
C.14      

Share 
capital   
£000s   
4,165        
-        
-        
324        
324        

4,489        
-   
-   
901   
901        
-        
5,390        

Capital 
reserves   
£000s   
186,707        
8,632        
(659 )      
30,598        
38,571        

225,278        
10,252        
(192 )      
42,338        
52,398        
-        
277,676        

Accumulated 
losses   
£000s   
(176,788 )      
-        
659        
-        
659        
(42,281 )      
(218,410 )      
-        
192        
-        
192        
(43,354 )      
(261,572 )      

The accompanying accounting policies and notes form an integral part of these financial statements. 

Total 
equity   
£000s   
14,084   
8,632   
-   
30,922   
39,554   
(42,281 ) 
11,357   
10,252   
-   
43,239   
53,491   
(43,354 ) 
21,494   

102 

 
 
 
 
  
  
 
 
 
  
  
   
 
 
 
  
      
  
      
  
      
  
      
  
      
  
        
         
       
  
      
  
   
  
   
  
   
  
      
  
      
  
      
 
SILENCE THERAPEUTICS PLC 

Notes to the Company Financial Statements  
Year ended 31 December 2022 

C.1 

General information 

103 

 
 
 
 
 
SILENCE THERAPEUTICS PLC 

C.2 

Basis of preparation 

These  financi

the  recognition,  measurement  and  presentation  requirements  of  international  accounting 
standards in conformity with the requirements of the Companies Act 2006, but it makes amendments where necessary 
in order to comply with the Act and take advantage of the FRS 101 disclosure exemptions. 

As permitted by FRS 101, the Company has taken advantage of the disclosure exemptions in relation to:  

Business combinations  

Share-based payment 

Financial Instruments  

Fair value measurement  

Presentation of a Cash Flow Statement  

Standards not yet effective  

Impairment of assets  

Related Party Transactions 

The  financial  statements  have  been  prepared  under  the  historical  cost  convention  as  modified  by  revaluation  to  fair 
value  of  the derivative  financial  instrument and  on  the going concern basis (see  note 2  in  the consolidated  financial 
statements). The financial statements are prepared in sterling, which is also the functional currency of the Company, 
and presented to the nearest thousand pounds.  

The principal accounting policies, which have been applied consistently, are as set out in note 2 of the consolidated 
financial statements except those that are Company specific and noted below.  

Going Concern  

The Company has incurred recurring losses since inception, including net losses of £43.4 million for the year ended 
December 31, 2022. As of December 31, 2022, the Company had accumulated losses of £261.6 million. The Company 
expects to incur operating losses for the foreseeable future as it continues its research and development efforts, seeks 
to obtain regulatory approval of its product candidates and pursues any future product candidates the  Company may 
develop. 

To-date,  the  Company  has  funded  its  operations  through  upfront  payments  and  milestones  from  collaboration 
agreements, equity offerings and proceeds from private placements, as well as management  of expenses and other 
financing options to support its continued operations. 

During 2021, the Company received $40.0 million (£30.8 million) of the upfront payments in respect of the AstraZeneca 
collaboration, $45 million from a private placement of ADSs (approximately $42.0 million / £30.8 million, net of expenses) 
and approximately $16.0 million (£10.7 million) of the upfront payment, (net of taxes withheld, based on the exchange 
rate  at  the payment  date),  related  to  the  Hansoh  Pharmaceutical  Group  Company  Limited  or  Hansoh,  collaboration 
executed on October 14, 2021. In August 2022 the Company raised additional funds through a registered direct offering 
with  aggregate  gross  proceeds  of  $56.5  million  (approximately  £46.4  million)  before  deducting  $4.1  million 
(approximately £3.3 million) in underwriting discounts, commissions and estimated offering expenses. As of December 
31, 2022, the Company had cash and cash equivalents and U.S. Treasury Bills of £70.4 million. 

104 

 
 
 
 
 
 
 
 
 
 
 
SILENCE THERAPEUTICS PLC 

The Company has the responsibility to evaluate whether conditions and/or events raise material uncertainty about its 
ability  to  meet  its  future  financial  obligations  as  they  become  due  within  one  year  after  the  date  that  the  financial 
statements  are  issued.  The  forecast  for  evaluating  the  going  concern  basis  of  the  Company  includes  continued 
investment  in  our  technology  platform  and  product  pipeline.  The  forecast  does  not  include  collaboration  milestones 
which have not been fully achieved or other assumptions for potential future non-dilutive or dilutive funding  sources. 
Based on this evaluation, the Company believes that its current cash and cash equivalents are only sufficient to fund its 
operating  expenses  through  the  first  quarter  of  2024.  This  indicates  that  a  material  uncertainty  exists  that  may  cast 
significant doubt on the Company
Company may be unable to 
realize assets and discharge liabilities in the normal course of business. 

The Company will need to raise additional funding to fund its operation expenses and capital expenditure requirements 
in  relation to  its  clinical  development  activities.  The  Company  may  seek  additional funding  through  public  or  private 
financings,  debt  financing  or  collaboration  agreements.  Specifically,  the  Company  may  receive  future  milestone 
payments of up to $14 million from existing collaboration agreements in the next 12 months which will extend the ability 
to  fund  operations  beyond  the  first  quarter  of  2024.  However,  these  future  milestone  payments  are  dependent  on 
achievement of certain development or regulatory objectives that may not occur. The Company has an authorized open 
market sale agreement and can potentially raise funds through the sale of ADSs. However, there is no assurance that 
we will be successful in obtaining sufficient funding on terms acceptable to us, or if at all. The inability to obtain future 
funding could impact; 
required to delay, reduce or eliminate some of its research and  development  programs,  or being unable to continue 
operations or unable to continue as a going concern.  

These  consolidated  financial  statements  have  been  prepared  assuming  that  the  Company  will  continue  as  a  going 
concern which contemplates the continuity of operations, realization  of assets and the satisfaction of  liabilities in  the 
ordinary course of business and do not include adjustments that would result if the  Company were unable to continue 
as a going concern. 

Investments in subsidiaries  

Investments in subsidiaries comprise shares in the subsidiaries and quasi-equity loans from the Company. Investments 
in shares of the subsidiaries are stated at cost less provisions for impairment in line with IAS 27 (Separate Financial 
Statements).  Quasi-equity  loans  are  stated  at  amortised  cost,  net  of  expected  credit  losses  in  line  with  IFRS  9 
(Classification and Measurement of Financial Instruments). 

Critical accounting judgements and key sources of estimation uncertainty 

best knowledge of current events and actions, actual results may ultimately differ from those estimates. 

The  critical judgements concerning  the  future,  and  other  key sources  of  estimation  uncertainty  at the balance sheet 
date, that have a significant risk of causing a material adjustment to the carrying amounts of assets and liabilities within 
the next financial year, are those relating to the following: 

the application of IFRS 15 in determining revenue from contracts with customers specifically: 

o 

o 

o 

the determination of the number of performance obligations (judgement); 

the allocation of the upfront payments between the performance obligations (judgement); 

the estimate of the future costs to be incurred; 

the carrying value of the investment in subsidiary undertakings as detailed in note C.6. 

105 

 
 
 
 
 
 
SILENCE THERAPEUTICS PLC 

C.3 

Income statement 

The Company has taken advantage of Section 408 of the Companies Act 2006 and has not included its own income 
statement in these financial statements.  

C.4 

Directors and staff costs 

remuneration, during the year for the Company were as follows: 

Wages and salaries 
Social security costs 
Share-based payments charge 
Other pension costs 

2022   
£000s   
10,249        
743        
10,252        
415        
21,659        

2021   
£000s   
7,414   
947   
8,632   
319   
17,312   

Remuneration detail for all Directors is presented in the Remuneration Committee report. See page 37 for further 
details. The total remuneration of the highest paid director was £5.9 million (2021: £1.5 million) 

The monthly average number of employees of the Company was as follows: 

Research and development and associated support services 
Administration 
Total average number of employees 

2022   
Number   

26        
16        
42        

2021   
Number   
18   
17   
35   

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SILENCE THERAPEUTICS PLC 

C.5 

Property, plant and equipment 

Cost 

At 1 January 2021 

Additions 
Disposals 

At 31 December 2021 
At 1 January 2022 

Additions 
Disposals 

At 31 December 2022 

Accumulated depreciation 

At 1 January 2021 

Charge for the year 
Eliminated on disposal 

At 31 December 2021 
At 1 January 2022 

Charge for the year 
Eliminated on disposal 

At 31 December 2022 

Net book value 

As at 31 December 2021 
As at 31 December 2022 

Intangible Assets 

Cost 

At 1 January 2021 

Additions 
Disposals 
Translation adjustment 

At 31 December 2021 
At 1 January 2022 

Additions 
Disposals 
Translation adjustment 

At 31 December 2022 

Accumulated depreciation 

At 1 January 2021 

Charge for the year 
Eliminated on disposal 
Translation adjustment 

At 31 December 2021 
At 1 January 2022 

Charge for the year 
Eliminated on disposal 
Translation adjustment 

At 31 December 2022 

Net book value 

As at 31 December 2021 
As at 31 December 2022 

Equipment and 

Right-of-use 

furniture   
£000s   

asset   
£000s   

721        
27        
-        
748        
748        
61        
(70)        
739        

637        
33        
-        
670        
670        
34        
(70)        
634        

78        
105        

346        
-        
-        
346        
346        
499        
(346)        
499        

43        
173        
-        
216        
216        
171        
(346)        
41        

130        
458        

Licenses and 
Software   
£000s   

Total   
£000s   

107   
23   
-  
-   
130   
130   
300   
-  
-   
430   

90   
16   
-  
-   
106   
106   
4   
-  
-   
110   

24   
320   

107   
23   
-  
-   
130   
130   
300   
-  
-  
430   

90   
16   
-  
-   
106   
106   
4   
-  
-  
110   

24   
320   

Total   
£000s   

1,067   
27   
-  
1,094   
1,094   
560   
(416)  
1,238   

680   
206   
-  
886   
886   
205   
(416)  
675   

208   
563   

107 

 
 
 
 
  
  
 
 
  
  
 
 
     
        
        
   
     
     
     
     
     
     
     
     
     
        
        
   
     
     
     
     
     
     
     
     
     
        
        
   
     
     
 
 
  
 
  
  
 
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
     
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
SILENCE THERAPEUTICS PLC 

C.6 

Investments in subsidiaries  

Company 

Investment in subsidiary undertakings 

2022   
£000s   
17,519        

2021   
£000s   
16,387   

The investment in subsidiary undertakings is made up as follows: 

Shares and loans in subsidiary undertakings 
At 1 January 2021 
Movement in the year 
At 31 December 2021 
Movement in the year 
At 31 December 2022 

Investment 

Quasi-equity 

at cost     
£000s   

loan     

£000s   

Impairment 
provision 
(Investment)     

£000s   

Impairment 
provision 

(Loan)     
£000s   

Net total   
£000s   

23,713        
-        
23,713        
-        
23,713        

36,058        
(582)        
35,476        
1,132        
36,608        

(20,360 )      
-        
(20,360 )      
-        
(20,360 )      

(22,442 )     
-       
(22,442 )     
-       
(22,442 )     

16,969   
(582 ) 
16,387   
1,132  
17,519   

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SILENCE THERAPEUTICS PLC 

Investments at cost total of £23.7 million (2021: £23.7 million) are analysed as follows: 

£23.3 million (2021: £23.3 million) relating to Silence Therapeutics GmbH. 

£0.2 million (2021: £0.2 million) relating to Silence Therapeutics Inc. 

The balance of the investments at cost of £0.2 million (2021: £0.2 million) relates to Innopeg Limited (2021: £0.1 
million) and Silence Therapeutics (London) Limited (2021: £0.1 million). 

Quasi-equity loans total of £36.6 million (2021: £35.5 million) are analysed as follows: 

At 31 December 2022, an interest-bearing unsecured loan of £14.2 million (2021: £13.0 million) was outstanding 
from Silence Therapeutics  plc  to Silence  Therapeutics  GmbH.  The  movement  in the year  includes  a  foreign 
exchange gain of £0.7 million (2021: £0.6 million) and accrued interest of £0.4 million (2021: £0.3 million).  

At  31  December  2022,  a  non-interest-bearing  unsecured  loan  of  £22.4million  (2021:  £22.4  million)  was 
outstanding  from  Silence  Therapeutics  plc  to  Silence  Therapeutics  (London)  Ltd.  This  quasi-equity  loan has 
been fully provided for. 

Impairment provision totalling £42.8 million (2021: 42.8 million) is analysed as follows: 

£20.2  million  (2021:  £20.2  million)  relating  to  Silence  Therapeutics  GmbH.  In  accordance  with  IAS  36 
Impairment of Assets, the carrying value of the net investment in Silence Therapeutics GmbH of £3.4 million 
(£3.4 million) has been assessed by comparing its carrying value to its recoverable amount. The recoverable 
amount is based on value in use. A discounted cash flow model has been used to make this assessment and 
management  determined that there was no impairment. The model is prepared  based on a 10 year forecast 
which  management  consider  to  be  an  accurate  measure  of  further  cash  flows.  The  discount  rate  used  was 
10.72% and resulting headroom was £12.9 million. Management has assessed that, if no milestones were to 
be achieved in 2023 or 2024, this would result a reduction the headroom by of £2.4 million. 

£0.2  million  (2021:  £0.2  million)  relating  to  the  investments  held  in  Silence  Therapeutics  (London)  Ltd  and 
Innopeg Ltd and they are not deemed to be recoverable. 

Silence  Therapeutics  plc  has  recorded  an  impairment  provision  against  the  quasi-equity  loans  in  Silence 
Therapeutics (London) Ltd and Innopeg Ltd (2021: £22.4 million) as they are not deemed to be recoverable. 

In considering the recoverability  of the loan with Silence Therapeutics GmbH, management have applied an 
expected credit  loss methodology under IFRS  9 and  calculated  that a  provision  of £30 thousand  is  required 
(2021: £30 thousand). 

109 

 
 
 
 
 
 
 
 
 
 
 
 
 
SILENCE THERAPEUTICS PLC 

Subsidiary companies 

The  principal  activity  of  all  subsidiaries  is  the  research  and  development  of  pharmaceutical  products.  All  subsidiary 
companies are consolidated in the 

Name 
Silence Therapeutics GmbH 

Silence Therapeutics (London) Ltd 
Innopeg Ltd 
Silence Therapeutics Inc. 

Name 
Silence Therapeutics GmbH 
Silence Therapeutics (London) Ltd 
Innopeg Ltd 
Silence Therapeutics Inc. 

Registered office address 

Place of 
incorporation 
and operation  

Principal 
technology 
area 

Proportion of 
ownership 
interest 

RNA 

   Robert-Rössle-Strasse 10, 13125 Berlin, Germany  
   27 Eastcastle Street, London, W1W 8DH 
   27 Eastcastle Street, London, W1W 8DH 

Germany  
England  
England  

therapeutics    
Dormant    
Dormant    

100 % 
100 % 
100 % 

  16192 Coastal Highway, Lewes, DE 19958, U.S.A.  

USA  

therapeutics    

100 % 

RNA 

Exempt from 
audit 
Yes   
Yes   
Yes   
Yes   

Exempt from 
filing financial 
statements 
No 
No 
No 
No 

C.7 

Cash and cash equivalents  

Cash at bank comprises balances held by the company in current and short-term bank deposits with an original maturity 
of three months or less. The carrying amount of these assets approximates to their fair value. 

Cash at bank and in hand 
U.S. Treasury Bills 
Short term bank deposits 
Total Cash and cash equivalents 

2022   
£000s   
41,237        
12,376    

454       
54,067        

2021   
£000s   
73,272   
-  
-   
73,272   

C.8 

Financial assets at amortised cost 

Non-current financial assets at amortized cost primarily relate to deposits for properties. 

Current financial assets at amortized cost, other than trade receivables as disclosed in C.12, include U.S. Treasury 
Bills (with maturities from purchase date over three months) of £16.3 million (2021: nil). 

Current financial assets at amortised cost 
Financial assets at amortised cost - non-current 
Total financial assets at amortised cost 

 U.S.Treasury Bills 

2022   
£000s   
16,328        
284        
16,612        

2021   
£000s   
-   
284   
284   

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SILENCE THERAPEUTICS PLC 

C.9 

Other current assets 

Prepayments 
VAT receivable 
Total other current assets 

C.10  Trade and other receivables 

Trade receivables 
Amount receivable from subsidiary undertaking 
Total trade and other receivables 

2022   
£000s   
8,064        
1,441        
9,505        

2022   
£000s   

915        
19        
934        

2021   
£000s   
4,206   
1,008   
5,214   

2021   
£000s   
331   
512   
843   

The Directors consider that the carrying amount of trade receivables approximates to their fair value. 

No interest is charged on outstanding receivables. There were no overdue trade receivables balances.  

The Group has applied an expected credit loss model to the balance and determined that £nil (2021: £nil) provision is 
required. 

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SILENCE THERAPEUTICS PLC 

C.11  Trade and other payables 

Trade payables 
Amount payable to subsidiary undertaking 
Social security and other taxes 
Accruals and other payables 
Total trade and other payables 

2022   
£000s   
3,105        
9,356        
379        
7,274        
20,114        

2021   
£000s   
3,535   
5,978   
254   
5,193   
14,960   

The Directors consider that the carrying amount of trade and other payables approximates to their fair value. Amounts 
payable to subsidiary undertakings are interest free and unsecured. 

C.12  Lease liability 

Lease liability - current 
Lease liability   non-current 
Total lease liability 

2022   
£000s   

183        
263    
446        

2021   
£000s   
112   
-  
112   

In  2022  the  lease liability  recognised  on  the  face of the  balance  sheet  comprises of the 
repayment of the principal portion of these lease liabilities for the year-ending 31 December 2022 was £0.2 million (2021: 
£0.2 million). 

C.13  Contract liabilities 

Contract  liabilities  comprise  entirely  deferred  revenue  in  respect  of  the  Mallinckrodt,  AstraZeneca  plc,  and  Hansoh 
research collaborations. 

Contract liabilities 
Contract liabilities 

 current 
 non-current 

2022   
£000s   
8,864        
63,485        
72,349        

2021   
£000s   
4,247   
72,501   
76,748   

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SILENCE THERAPEUTICS PLC 

C.14  Capital reserves 

The capital redemption reserve was created in 2012 following the reduction of nominal share capital to 0.1p per share. 
It is required under Section 733 of the Companies Act 2006, held to maintain the capital of the Company when shares 
are bought back and subsequently cancelled without court approval. 

Due to the size of the deficit on the accumulated losses account, the Company has no distributable reserves. 

The share premium account reflects the premium to nominal value paid on issuing shares less costs related to the issue. 
The merger reserve was created on issuance of shares relating to the acquisition of Silence Therapeutics GmbH. 

Share 
premium 
account 

£000s     
153,734       
32,585       
-       
460       

(2,447)      
30,598       
184,332       
45,533       
-       
153       

Merger 
reserve 

Share-based 
payment reserve 

Capital 
redemption 
reserve 

£000s     
22,064       
-       
-       
-       

-       
22,064       
-       
-       
-       

£000s     
5,715       
-       
8,632       
(659 )     

£000s     
5,194       
-       
-       
-       

7,973       
13,688       
-       
10,252       
(192 )     

-       
5,194       
-       
-       
-       

(3,348)      
42,338       
226,670       

-      
-       
22,064       

10,060       
23,748       

-       
5,194       

Total 

£000s   
186,707   
32,585   
8,632   
(199 ) 

(2,447)  
38,571   
225,278   
45,533   
10,252   
(39 ) 

(3,348)  
52,398   
277,676   

At 1 January 2021 
Shares issued 
On options in issue during the year 
On options exercised during the year 
Costs capitalised in respect of issuance of shares during the 
period. 
Movement in the year 

At 31 December 2021 

Shares issued 
On options in issue during the year 
On options exercised during the year 
Costs capitalised in respect of issuance of shares during the 
period. 
Movement in the year 
At 31 December 2022 

C.15  Related party transactions 

We have engaged in the following transactions with our directors, executive officers or holders of more than 10% of our 
outstanding share capital and their affiliates, which we refer to as our related parties. 

In  2022,  we  paid  Gladstone  Consultancy  Partnership,  a  company  controlled  by  our  Non-Executive  Chairman,  £60 
thousand for consulting and advisory services to be provided by Iain Ross (2021: nil). The amounts payable were settled 
before the relevant year ends. 

C.16 

 Post balance sheet events 

There were no post balance sheet events as of the filing date. 

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SILENCE THERAPEUTICS PLC 

Company Information and Advisers 

Secretary 
Sarah Murphy 

Registered Office  
27 Eastcastle Street 
London W1W 8DH, 
United Kingdom 

Registered Number 
02992058 

Registrar 
Link Asset Services 
65 Gresham Street 
London EC2V 7NQ, 
United Kingdom 

Independent Auditors 
PricewaterhouseCoopers LLP 
Chartered Accountants and Statutory Auditors 
The Maurice Wilkes Building 

Cambridge CB4 0DS 
United Kingdom 

Legal Adviser 
Cooley (UK) LLP 
22 Bishopsgate 
London EC2N 4BQ 
United Kingdom 

Silence Trademarks 
Silence 
Silence Therapeutics 
The Silence Therapeutics logo 
AtuRNAi 
mRNAi GOLD

114 

 
 
 
 
SILENCE THERAPEUTICS PLC 

Silence Therapeutics plc 

United Kingdom 
72 Hammersmith Road 
London, W14 8TH 
+44(0)20 3457 6900 

Germany 
Robert-Rossle-Str.10 
D-13125 Berlin 
+49 30 9489 2800 

United States 
221 River Street 
9th Floor 
Hoboken, NJ 07030 

www.silence-therapeutics.com