Program to begin at 8:30 AM ET N o t F o r P r o m ot io n a l U s e , F o r I n v e s t o r s O n ly

Program to begin at 8:30 AM ET N o t F o r P r o m ot io n a l U s e , F o r I n v e s t o r s O n ly

Forward - Looking Statements Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 2 This Presentation contains forward - looking statements for purposes of the Private Securities Litigation Reform Act of 1995 (the "Act") . Cytokinetics disclaims any intent or obligation to update these forward - looking statements and claims the protection of the Act's Safe Harbor for forward - looking statements . Examples of such statements include, but are not limited to, statements related Cytokinetics' research and development and commercial readiness activities, including the initiation, conduct, design, enrollment, progress, continuation, completion, timing and results of clinical trials, projections regarding growing prevalence, low survival rates and market opportunity in heart failure, hypertrophic cardiomyopathy (HCM) or amyotrophic lateral sclerosis (ALS) ; projections regarding the size of the addressable patient population for omecamtiv mecarbil, aficamten or reldesemtiv ; Cytokinetics' commercial readiness for omecamtiv mecarbil ; the likelihood of approval and timing for regulatory approval of omecamtiv mecarbil or any of our other drug candidates ; the submission of a new drug application (NDA) to the FDA for omecamtiv mecarbil in 2021 ; the timing of commencement of COURAGE - ALS, a phase 3 clinical trial of reldesemtiv or the timing of commencement of a phase 3 clinical trial of aficamten ; the timing of any potential commercial launch of our product candidates, if approved ; commercial opportunities for our product candidates ; Cytokinetics' cash runway, cash balances and estimated cash expenditures ; interactions with the FDA ; the properties, potential benefits and commercial potential of aficamten, omecamtiv mecarbil , reldesemtiv and Cytokinetics' other drug candidates . Such statements are based on management's current expectations ; but actual results may differ materially due to various risks and uncertainties, including, but not limited to, potential difficulties or delays in the development, testing, regulatory approvals for trial commencement, progression or product sale or manufacturing, or production of Cytokinetics' drug candidates that could slow or prevent clinical development or product approval, including risks that current and past results of clinical trials or preclinical studies may not be indicative of future clinical trial results, patient enrollment for or conduct of clinical trials may be difficult or delayed, Cytokinetics' drug candidates may have adverse side effects or inadequate therapeutic efficacy, the FDA or foreign regulatory agencies may delay or limit Cytokinetics' ability to conduct clinical trials, and Cytokinetics may be unable to obtain or maintain patent or trade secret protection for its intellectual property ; Cytokinetics may incur unanticipated research, development and other costs or be unable to obtain financing necessary to conduct development of its products ; standards of care may change, rendering Cytokinetics' drug candidates obsolete ; and competitive products or alternative therapies may be developed by others for the treatment of indications Cytokinetics' drug candidates and potential drug candidates may target . These forward - looking statements speak only as of the date they are made, and Cytokinetics undertakes no obligation to subsequently update any such statement, except as required by law . For further information regarding these and other risks related to Cytokinetics' business, investors should consult Cytokinetics' filings with the Securities and Exchange Commission (the "SEC")

Stuart Kupfer, M.D. SVP , C h i e f M e d i c a l O ff i c e r A nd r e w C a ll o s EVP , C h i e f C o mm e r c i a l O f f i c e r F a d y M a li k , M .D . , P h .D . EVP , R e s ea r c h & D e v e l o p m e n t Company Speakers R ob e r t B l u m P r e s i d e n t & C E O J o a nn a S i e g a l l S e n i o r M a n a g e r , Corporate Communications & Investor Relations Jennifer Laux VP , C a r d i o v a s c u l a r Marketing S t e ve H e i t n e r , M . D . S e n i o r M e d i c a l D i r e c t o r , C li n i c a l R e s ea r c h , Cardiovascular C h i n g J a w Chief Financial Officer Diann Potestio VP , G l o b a l V a l u e , A cc e s s & D i s t r i b u t i o n Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 3

Expert Panel T a r i q A h m a d , M D , M P H A ss o c i a t e P r o f e s s o r o f M e d i c i n e ; M e d i c al D i r ec t o r o f A d v a n ce d He a r t F a i l u r e , C a r d i o va s c u l a r M e d i c i n e , Y a l e S c h o o l o f M e d i c i ne A lan n a M o rr i s , M D M S c , F H F S A , F A CC , F A H A A ss o c i a t e P r o f e s s o r o f M e d i c i n e , D i v i s i o n o f C a r d i o l o g y ; D i r ec t o r o f He a r t F a i l u r e R ese a r c h , E m or y U n i v e r s i t y C li n i c a l C a r d i o v a s c u l ar R ese a r c h I n s t i t u t e Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 4

Charting the Commercial Course: Today's Agenda Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 5 Topic Presenter Intro J o a nn a S i e g a l l Welcome R o b e r t B l u m H e a r t Fa il u r e L a n d s c a p e F a d y M a li k , M D , P h D O m e c a m t i v M e c a r b i l : G A L A C T I C - HF S t u a r t Ku p f e r , M D E xp e r t P a n e l D i s c u s s i o n Tariq Ahmad, MD, Alanna Morris, MD O m e c a m t i v M e c a r b i l : F illi n g a n U n m e t P at i e n t Nee d A n d r e w C a ll o s U S G o - t o - M a rk e t S t r a t e g y Andrew Callos, Jennifer Laux, Diann Potestio Q&A B r e a k ( a pp r o x . 10 : 15 A M ) H C M L a n d s c a p e A n d r e w C a ll o s A f i ca m t e n : P o t e nt i a l Ne x t - i n - Cl a ss T h e r a p y S t e ve H e i t ne r , M D F r a n c h i s e S t r a t e g y A n d r e w C a ll o s F i n a n c i a l F o un d a t i o n & C or p or a t e D e v e l o p m e n t C h i n g J aw Q&A Cl o s i n g R e m a rk s R o b e r t B l um

Engaging in Today's Meeting Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 6 In Person Attendees: Masks : Masks are not required for those who are fully vaccinated. However, we encourage mask wearing whenever you are not eating or drinking. Refreshments : Please help yourself to coffee and breakfast. We will have boxed lunches available for all attendees at the end of our program. Questions : To ask a question please raise your hand and we will bring a microphone to you. Online Attendees: Resources : Use the tabs to the left to view speaker bios, the event agenda and supplementary resources. Questions : To ask a question type your question into the tab called "Ask a Question". Questions will be relayed to our team in the room during the event. Technical Issues : Visit the "Help Desk" tab for support related to any technical issues .

Introduction Robert Blum, President & CEO N o t F o r P r o m ot io n a l U s e , F o r I n v e s t o r s O n ly

8 T o b r i n g f o r w a r d n e w m e d i c i n e s t o i m p r o ve t h e h e a l th s p a n o f p e op l e w i t h devastating cardiovascular and neuromuscular diseases of impaired muscle function. Sarcomere Directed Therapies OUR MISSION

Our vision is to be the leading muscle biology biopharma company that m e a n i n g f u ll y i m pr o v e s t h e li v e s of patients with diseases of impaired muscle function through access to our pioneering medicines A c h i e v e r e g u l a t o r y a pp r o va l s f o r a t l e a s t two drugs arising from our pipeline B uil d c o mm e r c i a l c a p a b ili t i e s t o m a r ke t a n d s e l l o u r m e d i c in e s r e f l e c t i v e o f t h e ir i nn o va t i o n a n d va l u e Generate sustainable and growing r e v e nu e s f r o m p r o d u c t s a l e s D o u b l e o u r d e v e l o p m e n t p i p e lin e t o in c lu d e t e n t h e r a p e u t i c p r o g r a m s Expand our discovery platform to muscle e n e r g e t i c s , g r o w t h a n d m e t a bo li s m B e t h e s c i e n c e - d r i v e n c o m p a n y p e o p l e w a n t t o j o i n a n d p a r t n e r w i t h As always, we will support disease advocacy groups elevating the patient voice and live by our values of integrity, fairness and compassion in all that we do . VI S I O N Leading with Science, Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 9

Executing On Our Vision Scientific innovation driven by m o d u l a t i n g c a r d i a c m y o s i n First - in - class myosin activator Next - in - class myosin inhibitor Expansion beyond contractility to muscle energetics, metabolism R e g u l a r i n p u t , c o ll a b o r a t i o n and guidance E l e v a t e p a t i e n t v o i c e Improve function, p e r f o r m a n c e a n d h e a l t h s p a n C u s t o m e r - c e n t r i c a pp r o a c h t o p o r tf o li o m a n a g e m e n t O v e r l a p b e t w e e n H F r E F a n d H C M a cc o un t s C o mm e r c i a l b u i l d i n H F r E F s u pp o r t s f u t u r e H C M business L i f e c y c l e m a n a g e m e n t extends and expands franchise Build a F r a n c h i se Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 10 L ea d w i t h Science M e t h od i c a ll y Investigate T h i n k L i k e a Patient P o s i t i ve P h a s e 3 r e s u l t s f r o m G A L A C T I C - H F ; N D A s u b m i s s i o n e x p e c t e d i n 2H 2 0 21 R e p o r t e d p o s i t i ve P h a s e 2 results from REDWOOD - HCM; P h a s e 3 c li n i c a l t r i a l e x p e c t e d b y year - end C li n i c a l t r i a l r e s u l t s f r o m M E T E O R I C - H F e x p e c t e d i n ea r l y 2022

Pipeline of Novel Muscle - Directed Drug Candidates * Astellas to provide co - funding in exchange for low single - digit royalty All drug candidates above are investigational products and are not approved as safe or effective for any indication. Research Pre - Clinical Phase 1 Phase 2 Phase 3 C A R D I A C M U S C L E Omecamtiv Mecarbil (Heart Failure) A fi c a m t e n ( o H C M , n H C M , H F p E F ) CK - 271 CK - 136 (Heart Failure, other) S K E L E T A L M U S C L E Reldesemtiv (ALS)* CK - 601 Additional Skeletal Muscle Activators OTHER Muscle Biology Directed Research Myosin - Targeted T r opon i n - T a r g e t e d Research Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 11

Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 1 2 One Molecular Target Supports Emerging CV Franchise A c t i n Tropomyosin T h i c k f i l a m en t M y o s i n h ea d M y o s i n l e v e r a r m C a l c i u m A T P Activate O m e c a m t i v Mecarbil I nh i b i t Aficamten 12 Myosin

HF Treatment Landscape Fady Malik, M.D., Ph.D. E V P , R e s e a r c h & D e v e l op m e n t N o t F o r P r o m ot io n a l U s e , F o r I n v e s t o r s O n ly

Heart Failure Is a Public Health Emergency 46% Increase in Americans living with HF through 2030 owing to aging population and decline in mortality 1 HF: heart failure 127% Cost increase of H F t h r o u g h 203 0 ( i n c r e a s i n g fr o m $43.6 2 b i llio n t o $69. 7 b i llio n )3 Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 14 50% HF patients who will die within 5 years 1 1. Benjamin EJ, et al. Circulation . 2018;137:e67 - e492; 1. Urbich, M., Globe, G., Pantiri, K. et al. A Systematic Review of Medical Costs Associated with Heart Failure in the USA (2014 - 2020). PharmacoEconomics 38, 1219 - 1236 (2020). https://doi.org/10.1007/s40273 - 020 - 00952 - 0 2. Heidenreich PA, Albert NM, Allen LA, Bluemke DA, Butler J, Fonarow GC, et al. Forecasting the impact of heart failure in the United States: a policy statement from the American Heart Association. Circ Heart Fail. 2013;6(3):606 - 19. https://doi.org/10.1161/HHF.0b013e318291329a. ~6.5 million Americans 20 years of age have HF; 1 million new HF cases occur annually 1

Hospitalization & Rehospitalization Rates Are Burdensome HF, heart failure; HFbEF, heart failure with borderline ejection fraction; HFpEF, heart failure with preserved ejection fraction; HFrEF, heart failure with reduced ejection fraction. 1. B e n j a m i n E J , et a l . C i r c u l a t i o n . 2019 ; 139 : e56 - e528 ; 2. Davis JD, et al. Am J Med . 2017;130:93.e9 - 93.e28. (a) In an investigational study of patients with an index hospitalization for HF from California, New York, and Florida from 2007 - 2011 (N=547,088). 3. Shah KS, et al. J Am Coll Cardiol . 2017;70:2476 - 2486. (b) Among HFrEF patients (n=18,398), HFbEF patients (n=3285), and HFpEF patients (n=18,299) in the GWTG - HF registry, a study of patients on Medicare and Medicaid services (N=39,982). GWTG - HF, G e t W i t h t h e G u i d e li n e s - H e a r t F a i l u r e 49% P a t i e n t s r ea d m i tt e d t o hospital within 5 years 3,b 24% P a t i en t s r e a d m i tt e d t o hospital within 30 days 2,a ~900,000 Annual HF hospitalizations in the US 1 Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 15 Despite treatment advances, nearly 50% of patients are readmitted to the hospital within 5 years 3,b

Foundational GDMT - Problem Solved? Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 16 2021 E S C G u i d e li n e s f o r t h e D i a g n o s i s a n d Treatment of A c u te a n d C h r o n i c Heart Failure G D M T : G u i d e l i n e d i r e c t ed m e d i c a l t h e r apy Source: Eur Heart J . 2021 Sep 21;42(36):3599 - 3726.

50 40 30 20 10 0 60 All - cause Death/ H F H o s p i t a l i z a t i o n H F H o s p i t a l i z a t i o n A l l C au s e D e a t h D uk e C o h o r t 1 N o t H o s p w / i n 1 y r H o s p w / i n 1 y r Not Yet - Event Rates in HFrEF Remain Startling High Event Rates in Placebo Group of GALACTIC - HF on Excellent GDMT 40 30 20 10 0 Primary O u t c o me HF Hospitalization C V D ea t h A l l C a u s e D e a t h E j e c t io n F r a c t io n 1 > m ed i a n m e d i a n I n c i d e n c e ( p e r 10 0 p a t i e n t - y e a r s ) 40 30 20 10 0 Primary O u t c o me HF Hospitalization C V D ea t h A l l C a u s e D e a t h N Y H A C l a s s * C l a s s I I C l a s s I I I / I V 40 30 20 10 0 Primary O u t c o m e HF Hospitalization C V D ea t h A l l C a u s e D e a t h NT - proBNP* m e d i a n > m e d i a n Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 17 1. T ee r li n k J e t a l , J A C C 202 1 2. C a rn i c e l l i A P et a l , J A m H ea r t A ss o c , 2021 * C yt o k i n e t i cs , D a t a o n F il e

Not Yet - Event Rates in HFrEF Remain Startling High Event Rates in Placebo Group of GALACTIC - HF on Excellent GDMT I n c i d e n c e ( p e r 10 0 p a t i e n t - y e a r s ) E j e c t io n F r a c t io n 1 > m ed i a n m e d i a n N Y H A C l a s s * C l a s s I I C l a s s I I I / I V 40 40 30 30 20 20 10 10 0 0 P r i m a r y H F C V D ea t h A l l C a u s e D e a t h P r i m a r y H F C V D ea t h A l l C a u s e D e a t h Outcome Hospitalization Outcome Hospitalization D uk e C o h o r t 2 N o t H o s p w / i n 1 y r H o s p w / i n 1 y r N T - p r o B N P * m e d i a n > m e d i a n 60 40 50 30 40 30 20 20 10 10 0 0 A l l - c a u s e D e a t h / H F H o s p i t a l i z a t i o n A l l C au s e D e a t h P r i m a r y H F C V D ea t h A l l C a u s e D e a t h HF Hospitalization Outcome Hospitalization M e d i c a l T h e r a p y i n H i g h e r R i s k G r o u p ACEi/ARB/ARNi 88% Beta - Blocker 94% MRA 77% M e d i c a l T h e r a p y i n H i g h e r R i s k G r o u p ACEi/ARB/ARNi 84% Beta - Blocker 93% MRA 77% Medical Therapy in Higher Risk Group ACEi/ARB/ARNi 77% Beta - Blocker 88% MRA 46% Medical Therapy in Higher Risk Group ACEi/ARB/ARNi 83% Beta - Blocker 93% MRA 75% Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 18 1. T ee r li n k J e t a l , J A C C 202 1 2. C a rn i c e l l i A P et a l , J A m H ea r t A ss o c , 2021 * C yt o k i n e t i cs , D a t a o n F il e

Higher Risk Patients Tolerate Less GDMT The sickest patients are the most difficult to treat with GDMT 90 80 70 60 50 40 30 20 10 0 Risk - Treatment Mismatch in HF: Canadian EFFECT Study Low Risk Average Risk High Risk 1 - Year M o r t a li t y R a t e 1 - Year Follow - Up At Hospital Discharge Lee D. JAMA . 2005;294:1240 - 1247 A C E I - B l o c k e r or ARB 90 - Day Follow - Up A C E I Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 19 A C E I - B l o ck e r or ARB P a t i en t s , % A C E I G D MT li m i t a t io n s R e n a l D ys f un c t i o n Azotemia Hypotension Hyperkalemia Angioedema Bradycardia Fatigue

A f t e r F o und a t i o n a l G D M T - W h a t N e x t ? Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 20 P a t i e n t s w i t h w o r s e n i n g H F n ee d a l t e r n a t i v e s GDMT: Guideline directed medical therapy E u r H e a r t J . 202 1 S e p 21 ; 42 ( 36 ) : 359 9 - 3726.

Significant Unmet Need in HFrEF Proprietary market research suggests need for novel therapy Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 21 Drugs that d o n o t a ff e c t r e n a l f un c t i o n Drugs that do not affect BP Drugs that e nh a n c e c a r d i a c performance Disease m o d i f y i n g therapies Drugs that i n c r e a s e Q o L Physicians say newly approved therapies have prolonged survival, decreased hospital v i s i t s , bu t s t il l s e e n ee d for other therapies that reduce mortality Most physicians recognize negative effect therapies such as aldosterone antagonists have on renal function B P o ft e n li m i t i n g f a c t o r fo r u p t i t r a t i o n a n d therapy initiation Need efficacious drugs that do not result in hypotension Need drugs that target novel/more specific molecular targets Need targets other than the neurohormonal pathway Need drugs that safely enhance contractility Increased EF most frequently mentioned desired measure Patient management w il l i m p r o v e w i t h d r u g s that increase QoL P a t i e n t Q o L d e c r ea s e s as they lose the ability to p e r fo r m d a il y t a s k s Market research suggests need f o r n o v e l t h e r a p y

GALACTIC - HF Stuart Kupfer, M.D., SVP, Chief Medical Officer O m e c a m t i v M e c a r b i l : N o t F o r P r o m ot io n a l U s e , F o r I n v e s t o r s O n ly

23 Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y Pivotal Phase 3 Trial Design An HF event defined as the presentation of the subject for an urgent, unscheduled clinic/office/ED visit, or hospital admission, with a primary diagnosis of HF, where the patient exhibits new or worsening symptoms of HF on presentation, has objective evidence of new or worsening HF, and receives initiation or intensification of treatment specifically for HF (Hicks et al, 2015). Changes to oral diuretic therapy do not qualify as initiation or intensification of treatment. L a n d m a r k c li n i c a l t r i a l r e s u l t s p u b li s h e d i n N E J M Overview Enrolled 8,256 patients at ~1,000 sites in 35 countries Primary Endpoint Composite of time to cardiovascular (CV) death or first HF event, whichever occurs first Secondary Endpoints T i m e t o C V d e a t h Change in Kansas City Cardiomyopathy Questionnaire Total S y m p to m s S co r e ( K CC Q T SS ) f r o m b a s el i n e t o W eek 2 4 T i m e t o f i r s t H F h o s p i t a li z a t i o n T i m e t o a l l - c a u s e d e a t h K e y D e s i g n P o i n t s D o s e o p t i m i z a t i o n b a s e d o n t r o u g h c o n c e n t r a t i o n o f o m e c a m t i v m e c a r b i l a t 2 w ee ks a n d 6 w ee ks H i g h r i s k p a t i e n t s e n r o ll e d f r o m i np a t i e nt a n d o u t p a t i e n t s e tt i n g s D e s i g n e d t o p r ov i d e 90 % s t a t i s t i c a l p o w e r t o a ss e s s r i s k o f CV d e a t h

24 Charting the Commercial Course : Analyst & Investor Day 2021 Baseline Demographics W o r s e n i n g H F p o pu lati o n w it h h ig h l e v e l o f G D M T Characteristic OM ( N =4120 ) Placebo ( N =4112 ) Demographics A g e ( y e a r s ) , m e d i a n ( Q 1 , Q 3 ) 6 6 ( 58 , 73 ) 6 6 ( 58 , 73 ) S e x , f e m a l e , n ( % ) 87 5 ( 21 . 2 ) 87 4 ( 21 . 3 ) W h i t e / A s i a n / B l a c k / o t he r , % 78/9/7/7 78/9/7/7 H e a rt F a il u re H i s t o ry a n d M e d i c a l C o nd i t i o n s L V E F ( % ) , m e a n ( S D ) 26 . 6 ( 6 . 3 ) 26 . 5 ( 6 . 3 ) NYHA class, II/III/IV, % 53/44/3 53/44/3 I s c he m i c e t i o l o g y , % 53.2 54.0 A t r i a l f i b / f l u tt e r a t s c r een i n g , % 27.8 26.7 T y p e 2 d i a b e t e s , % 40.1 40.3 Characteristic OM ( N =4120 ) Placebo ( N =4112 ) Vitals and Laboratory Parameters N T - p r o B N P ( pg / m L ) , m e d i a n ( Q 1 , Q 3 ) 1977 ( 980 , 4061 ) 2025 ( 1000 , 4105 ) S B P ( mm Hg ) , m e a n ( S D ) 11 6 ( 15 ) 11 7 ( 15 ) H e a r t r a t e , m e a n ( S D ) 7 2 ( 12 ) 7 2 ( 12 ) eG F R ( m L / m i n / 1 . 73 m 2 ) , m e d i a n ( Q 1 , Q 3 ) 59 ( 44 , 74 ) 59 ( 44 , 74 ) Cardiac TnI (ng/mL), median (Q3) 0 . 02 7 ( 0 . 052 ) 0 . 02 7 ( 0 . 052 ) M e d i c a t i o n s a n d C a r d i a c D e v i c e s ACEI/ARB/ARNi , % 87 87 ARNi, % 20 19 B B , % 94 94 MRA, % 78 78 S G L T 2 i , % 2.5 2.8 CRT, % 14 14 ICD, % 32 31 ACEi, angiotensin - converting enzyme inhibitor; ARB, angiotensin receptor blocker; ARNi, angiotensin receptor - neprilysin inhibitor; BB, beta blocker; CRT, cardiac resynchronization therapy; eGFR, estimated glomerular filtration rate; fib, fibrillation; hsTnI, high - sensitivity troponin I; ICD, implantable cardioverter - defibrillator; LVEF, left ventricular ejection fraction; MRA, mineralocorticoid receptor antagonist; Q, quartile; SBP, systolic blood pressure; SGLT2i, sodium - glucose co - transporter 2 inhibitor. Teerlink JR et al., Cardiac Myosin Activation with Omecamtiv Mecarbil in Systolic Heart Failure; N Eng J Med 2020, 384:105 - 116.

Positive Primary Composite Endpoint Time to first HF event or CV death - 8% relative risk reduction Placebo 4112 3310 2889 2102 1349 647 141 OM 4120 3391 2953 2158 1430 700 164 Patients at risk, n C u m u l a t i v e i n c i d en c e , % 0 0 6 12 18 24 M o n t h s ( 3 0 d ay s ) s i n c e r a n do m i z a t i o n 30 36 50 45 40 35 30 25 20 15 10 5 P l a c e b o Om e c a m t i v mecarbil HR = 0.92 ( 95 % C I , 0 . 8 6 - 0 . 99 ) P = 0 . 02 5 Teerlink JR et al., Cardiac Myosin Activation with Omecamtiv Mecarbil in Systolic Heart Failure; N Eng J Med 2020, 384:105 - 116. Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 25

T r ea t m e n t E ff e c t I n c r ea s e d P r o g r e ss i v e l y A s B a s e li n e L V E F D e c r ea s e d 10 15 20 25 E j e c t io n f r a c t io n ( % ) 3 0 35 10 20 30 40 60 50 I n c i d e n c e R a t e ( p e r 10 0 p y ) Placebo O m e c a m t i v mecarbil T r ea t m e n t Effect T r e a t m e n t E f f e c t ( R a t i o ) 1.2 1.0 0.8 0 . 6 10 15 30 35 20 25 E j e c t io n f r a c t io n ( % ) R e l a t i v e T r ea t m e n t E f f e c t o n P r i m a r y E n dpo i n t Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 26 I n c id en c e o f P r i m a r y C o m po s i t e E n dpoi n t 5,842 patients 2414 patients A R R = A b s o l u t e R i s k R e d u c t i o n RR R = R e l a t i v e R i s k R e d u c t i o n Teerlink JR., Diaz R., Felker GM., et al. Effect of Ejection Fraction on Clinical Outcomes in Patients treated with Omecamtiv Mecarbil in GALACTIC - HF. JACC. 2021

Greater Treatment Effect with Higher NT - proBNP McMurray JM, Efficacy of omecamtiv mecarbil in HFrEF according to NT - proBNP level: Insights from the GALACTIC - HF trial, ESC Heart Failure 2021, June 2021 H R = 1 ( un i t y ) 95%CI Continuous HR H R = 1 ( un i t y ) P l a c e b o b e tt e r O M b e tt e r P r i m ar y C o m po s i t e O u t c o m e N Tp r o B N P 200 50 0 100 0 2000 5000 10000 20000 1.8 1.6 1.4 1.2 1 T r e a t m e n t E f f e c t .8 .6 .4 H F H o s p i t a li z a t i o n s Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 27 N Tp r o B N P 200 50 0 100 0 2000 5000 10000 20000 1.8 1.6 1.4 1.2 1 T r e a t m e n t E ff e c t .8 .6 .4 Primary Composite Outcome: Time to first HF event or CV death

Greater Treatment Effect in Higher - Risk, Worsening HF Results of the primary outcome in pre - specified subgroups showed greater treatment effect in patients with markers of worsening heart failure, i n c l u d i n g p a t i e n t s w i t h L VEF 28%: (n=4,456) HR 0.84; 95% CI 0.77, 0.92 Subgroup N o. of E v e n t s / N o. of P a t i e n t s H a z a r d R a t i o ( 95 % C l ) Norm p - v a l u e ARR A l l P a t i e n t s 3103 / 82 3 2 0.92 (0.86, 0.99) 0.025 2.1% L V E F 28 % 1821 / 445 6 0 . 8 4 (0 . 77 , 0.92) <0.001 4.9% Outpatients 1255 / 330 4 0.83 (0.75, 0.93) 0.001 5.0% Inpatients 566/1152 0.86 (0.73, 1.02) 0.084 3.9% H o s p < 3 m o s 1200 / 268 8 0.83 (0.74, 0.93) 0.001 5.2% C l a s s III / I V 1055/2132 0.80 (0.71, 0.90) <0.001 7.0% NT - proBNP >2000 1249 / 24 3 1 0.77 (0.69, 0.87) <0.001 8.1% S B P <11 0 843 / 1 82 0 0.81 (0.70, 0.92) 0.002 7.4% 0 . 5 0.8 1.0 1.2 OM P l a c e b o Better Better Teerlink JR et al., Cardiac Myosin Activation with Omecamtiv Mecarbil in Systolic Heart Failure; N Eng J Med 2020, 384:105 - 116. Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 28

Greater Treatment Effect in More Severe HF Severe HF defined as NYHA III - IV, EF 30%, HF hospitalization in last 6 months T r ea t m e n t e ff e c t f o r p r i m a r y endpoint in severe HF HR = 0.80 (0.71, 0.90) Absolute risk reduction 8.3 events/100 pt - years NNT = 12 Felker GM, Omecamtiv Mecarbil in Patients with Severe Heart Failure: An Analysis from GALACTIC - HF, ESC Heart Failure 2021, June 2021 Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 29

Clinically Meaningful Treatment Effect in North America Significant Risk Reduction of the Primary Composite Outcome Primary Composite Outcome: Time to first HF event or CV death P r i m a r y O u t c o m e , N o r t h A m e r i c a 0 . 5 0 0 . 4 0 0 . 3 0 0 . 2 0 0 . 1 0 0 . 0 0 0 6 12 24 30 18 Months 36 H R 0.85 95 % C I ( 0.73 , 0.99 ) P 0.04 P l a c e b o O m e c a m t i v Mecarbil Primary Outcome, Rest - of - World H R 0.94 95 % C I ( 0.87 , 1.02 ) P 0.14 0 . 5 0 0 . 4 0 0 . 3 0 0 . 2 0 0 . 1 0 0 . 0 0 0 6 12 24 30 18 M o n t h s 36 P l a c e bo Om e c a m t i v Mecarbil Teerlink JR et al., Cardiac Myosin Activation with Omecamtiv Mecarbil in Systolic Heart Failure; N Eng J Med 2020, 384:105 - 116. Differences e m e r g e e a r l y Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 30 a nd r e m a i n consistent o v e r t i m e

Safety and Tolerability Profile Comparable to Placebo Variable Omecamtiv Mecarbil (N=4110) Placebo ( N =4101 ) R e l a t i v e R i s k o r D i ff e r en c e (95% CI) Laboratory value change from baseline to Week 24 S y s t o li c b l oo d p r e ss u r e - mm Hg , m e a n ( S D ) 1 . 4 ( 15 . 3 ) 1 . 5 ( 15 . 6 ) - 0 . 1 ( - 0 . 9 , 0 . 6 ) H e a r t r a t e , bp m , m e a n ( S D ) - 2 . 1 ( 12 . 6 ) - 0 . 5 ( 12 . 8 ) - 1 . 6 ( - 2 . 2 , - 1 . 0 ) Cardiac Troponin I, ng/L, median (Q1, Q3) 0 . 00 4 ( - 0 . 002 , 0 . 021 ) 0 . 00 0 ( - 0 . 009 , 0 . 008 ) 0 . 00 4 ( 0 . 003 , 0 . 005 ) NT - proBNP, pg/mL, median (Q1, Q3) - 25 1 ( - 1180 , 295 ) - 18 0 ( - 915 , 441 ) 0 . 9 0 ( 0 . 86 , 0 . 94 ) Adverse events (AEs) Any serious AE, n (%) 237 3 ( 57 . 7 ) 243 5 ( 59 . 4 ) 0 . 9 7 ( 0 . 94 , 1 . 01 ) D r u g d i s c o n t i nu a t i o n d u e t o A E , n ( % ) 37 1 ( 9 . 0 ) 38 2 ( 9 . 3 ) 0 . 9 7 ( 0 . 85 , 1 . 11 ) A d v e r s e e v en t s o f i n t e r e s t Ventricular tachyarrhythmias 29 0 ( 7 . 1 ) 30 4 ( 7 . 4 ) 0 . 9 5 ( 0 . 82 , 1 . 11 ) Torsade de pointes/QT prolongation 17 6 ( 4 . 3 ) 19 5 ( 4 . 8 ) 0 . 9 0 ( 0 . 74 , 1 . 10 ) S A E o f v en t r i c u l a r a rr h yt h m i a r e q u i r i n g treatment 11 9 ( 2 . 9 ) 12 7 ( 3 . 1 ) 0 . 9 3 ( 0 . 73 , 1 . 20 ) Adjudicated major cardiac ischemic events, n (%) 20 0 ( 4 . 9 ) 18 8 ( 4 . 6 ) 1 . 0 6 ( 0 . 87 , 1 . 29 ) Myocardial infarction 12 2 ( 3 . 0 ) 11 8 ( 2 . 9 ) H o s p i t a li z e d f o r un s t a b l e a n g i n a 2 5 ( 0 . 6 ) 1 2 ( 0 . 3 ) C o r o n a r y r e v a s c u l a r i z a t i o n 11 5 ( 2 . 8 ) 11 7 ( 2 . 9 ) Adjudicated Strokes 7 6 ( 1 . 8 ) 11 2 ( 2 . 7 ) 0 . 6 8 ( 0 . 51 , 0 . 91 ) Teerlink JR et al., Cardiac Myosin Activation with Omecamtiv Mecarbil in Systolic Heart Failure; N Eng J Med 2020, 384:105 - 116. Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 31

Greater Effects in HF Patients with Highest Need Significant risk reduction of the primary composite endpoint in patients with worsening HF receiving excellent GDMT Greater treatment benefit in higher risk patients Lower baseline LVEF Higher baseline NT - proBNP Higher baseline NYHA Class Good safety and tolerability with no adverse effects on blood pressure, heart rate, renal function, or electrolytes Teerlink JR et al., Cardiac Myosin Activation with Omecamtiv Mecarbil in Systolic Heart Failure; N Eng J Med 2020, 384:105 - 116 Teerlink JR., Diaz R., Felker GM., et al. Effect of Ejection Fraction on Clinical Outcomes in Patients treated with Omecamtiv Mecarbil in GALACTIC - HF. JACC. 2021. Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 32

Selected Comments from Key Opinion Leaders " T h i s i s t h e h ol y g r a i l f o r i n o t r o p e s " "The first inotropic agent that doesn't increase arrhythmias or mortality" "OM's greatest potential is in severe, sicker patients " " Omecamtiv mecarbil can serve a large, unmet need " " U n i q u e m e c h a n i s m t h a t i s a v i a b l e t a r ge t " "Molecule is innovative and gets to the root cause of HF " " S a f e t y i s ve r y g oo d - i t o p e n s i t u p t o a w i d e r a n g e o f p a t i e n t s " "Potential utility in patients unable to tolerate or titrate GDMT" " L a c k o f e ff e c t o n B P i s a hu g e p l u s " Overall M O A S a f e ty Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 33

Expert Panel Moderated by Fady Malik, M.D., Ph.D., EVP, Research & Development N o t F o r P r o m ot io n a l U s e , F o r I n v e s t o r s O n ly

35 Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y Expert Panel T a r i q A h m a d , M D , M P H A ss o c i a t e P r o f e s s o r o f M e d i c i n e ; M e d i c al D i r ec t o r o f A d v a n ce d He a r t F a i l u r e , C a r d i o va s c u l a r M e d i c i n e , Y a l e S c h o o l o f M e d i c i ne A lan n a M o rr i s , M D M S c , F H F S A , F A CC , F A H A A ss o c i a t e P r o f e s s o r o f M e d i c i n e , D i v i s i o n o f C a r d i o l o g y ; D i r ec t o r o f He a r t F a i l u r e R ese a r c h , E m or y U n i v e r s i t y C li n i c a l C a r d i o v a s c u l ar R ese a r c h I n s t i t u t e

Filling an Unmet Patient Need Andrew Callos, EVP, Chief Commercial Officer O m e c a m t i v M e c a r b i l : N o t F o r P r o m ot io n a l U s e , F o r I n v e s t o r s O n ly

Omecamtiv Mecarbil: Value Proposition K E Y M A RK E T D Y N A M I C S OM VALUE PROPOSITION OM delivers clinical v a l u e t o w o r s en i n g H F patients OM is an add - on therapy for worsening HF patients OM reduces hospitalizations and their associated costs 1 Large unmet need Limitations of current regimens High cost burden to society 1. Felker GM. ESC Heart Fail 2021 Oral Presentation. Data based on post hoc analyses. Investigational product. Not approved as safe or effective for any indication. Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 37

K e y U S H F r E F M a r k e t D y n a m i cs Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 38 1. National Center for Health Statistics. National Health and Nutrition Examination Survey (NHANES) as accessed 4/1/2019 at website. https://www.cdc.gov/nchs/nhanes and Benjamin 2019 Circulation. 2019;139:e56 - e528. DOI: 10.1161/ 2. EF based on distribution as presented in Dunlay et al Circ Heart Fail. 2012;5:720 - 726, 3. Greene et. al.: Medical Therapy for Heart Failure With Reduced Ejection Fraction The CHAMP - HF Registry . JACC, VOL. 72, NO. 4, 2018 4. Angaran P, Association of Left Ventricular Ejection Fraction with Mortality and Hospitalizations, Journal of the American Society of Echocardiography, July 2020. 5. Fitch K , The Cost Burden for WHF in the Medicare FFS Population, Milliman, 2015 Large HFrEF patient population , ~ 50% of total HF (~3M patients) 1 HFrEF with worsening symptoms ( 30% EF), about 2/3 rd of HFrEF (~2M patients) 2 Large un m e t n ee d Li m ita t i o n s o f c u rr e n t t r e at m e n ts H ig h c o s t bu r d e n t o s o c i ety Few patients receive guideline - recommended target doses of current treatments 3 Additional treatment options are needed in patients with EF 30% Driven by hospitalizations, HF is the biggest cost driver in Medicare : 4% of costs 5 Rate of hospitalization increases as EF declines 4

Large and Growing Heart Failure Patient Population 1. National Center for Health Statistics. National Health and Nutrition Examination Survey (NHANES) as accessed 4/1/2019 at website. https://www.cdc.gov/nchs/nhanes/ . - data from 2013 - 2016 as quotes in Benjamin 2019 Circulation. 2019;139:e56 - e528. DOI: 10.1161/ 2. EF based on distribution as presented in Dunlay et al Circ Heart Fail. 2012;5:720 - 726, 3. 2.1% annual growth rate:1.9% annual growth rate of patient population 65+ (UN World Populations Prospects Nov 2019) and a 0.2% mortality impact of HF treatment (doi: 10.1136/bmj.l223 | BMJ 2019;364:l223) H F r E F P o pu l a ti o n Heart Failure I n c l u d i n g H F p E F 4.0M 3 3.1M 2 Prevalence in Adults (18+, USA) 2020 Estimates 2032 Estimates 6.2M 1 8.0M 3 H F r E F & E F 30 % 2.6M 3 2.0M 2 Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 39

H F r E F T r ea t m e n t A p p r o a c h e s a n d G u i d e li n e s A r e E vo lv i n g T r e n d i n t r e at m e n t a pp r o a c h e s t o p r e s c r i b e i n i t i a l m u l t i - d r u g r e gi m e n s ea rl i e r A l s o r e f l e c t e d in upd at e d 202 1 E S C g u i de li n e s 2 ACEi angiotensin - converting - enzyme inhibitor; ARB, angiotensin receptor blocker; ARNi: angiotensin receptor - neprilysin inhibitor; MRA: mineralocorticoid receptor antagonist; SGLT2: sodium - glucose co - transporter - 2 1. Maddox TM, et al J Am Coll Cardiol 2021; 77(6): 772 - 810 ( https:// www.acc.org/Latest - in - Cardiology/ten - points - to - remember/2021/01/2021/21/56/2021 - Update - Expert - Consensus - for - HFrEF.) 2. European Heart Journal (2021) 42, 3599 - 3726 ivabradine a nd hydralazine + nitrate a nd thiazide diuretic / / or or R AA S i : A RN i (preferred) or ACEi or ARB + beta - blocker + Loop diuretic (as needed) + MRA + SGLT2 inhibitor Plus "SGLT2 should be considered" 1 "If resting HR is 70 bpm in sinus rhythm" 1 "For persistently symptomatic Black patients" 1 C u rr e n t A CC / AH A S t e p 1 g u i d e l i n e s "aldosterone antagonist should be considered" 1 ARNi "preferred" R AA S i 1 Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 40

Recent Entrants Have Expanded Treatment Options H F r E F e xp a n s i o n ( A CC / E S C guidelines) & LIFE study results I n c r ea s ed S G L T c o m p e t i t i o n Indicated following HF hospitalization or outpatient IV diuretics F i r s t S G L T t o H F m a r k e t Company press releases or investor events HFrEF J ul 2015 HFpEF H 1 202 3 HFrEF M a y 2020 H F i n T 2 D O c t 2019 HFrEF J a n 20 2 1 + + HFpEF J a n 202 1 T O D A Y HFrEF HFpEF A ug 202 1 H 2 202 2 K e y h i s t o r i c a l a n d a n t i c ip a t e d t i m e li ne s 2015 2019 2020 2021 2022 2023 Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 41

Co - Morbidities & Tolerability Can Lead to Under - Treatment Low BP Renal I n s u ff i c i en c y E l e v a t e d S e r u m Potassium % P a t i en t s R e c e i v i n g Target Dose ACEi/ARB X X X 17% ARNI X X X 14% B e t a B l o c k e r X 28% MRAs X X X 77% P a ti e n t s n o t r e a c h i n g re c o mm e n d e d d o s e s , li n k e d t o h i g h e r m o rt a l it y Conditions of concern Due to Co - Morbidity and/or Tolerability Implications for patients Confirmed in registries and primary research Greene et. al.: Medical Therapy for Heart Failure With Reduced Ejection Fraction The CHAMP - HF Registry . JACC, VOL. 72, NO. 4, 2018 ; HCP interviews " O b v i ou s l y [ g o a l i s t o ] h e l p i n c r e a s e t h e i r l on g e v i ty , reduce their morbidity and mortality with [being] able to tolerate the s i d e e ff e c t s o f t h e m e d i c a t i on s . " - KOL Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 42

HF Patients Often Cycle Through Frequent Hospitalizations 24% ~25 - 50% 44% 66% Heart Failure Hospitalization <1 m o n t h 4 ,6 <2 m o n t h s 7 <6 months 5 <12 m o n t h s 3 ,8 . . . Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 43 1 , A d a m s e t a l . A m H e a r t J 2006 ; 149 : 20 9 - 16 2 . C h en et a l . J A M A 2011 ; 306 : 1669 - 78 3. D i c k s t e i n e t a l . E u r H e a r t J 2008 ; 29 : 2388 - 442 4. Korda,, et al. BMC Health Serv Res . 2017;21;17(1):220. 5. Krumholz et al. Arch Intern Med 1997;15799 - 105 6. Krumholz et al. Circ Cardiovasc Qual Outcomes 2009;2(5):407 - 13 7. L o e h r e t a l . A m J C a r d i o l 2008 ; 101 : 1016 - 22 8. Whellan et al. Circulation 2010 Jan;3(1):33 - 40 9. Dunlay et al J Am Coll Cardiol. 2009 Oct 27; 54(18): 1695 - 1702. Almost 2 in 3 patients re - hospitalized within 12 months Majority have 3 or more heart failure hospitalizations over their lifetime 9

Lower EF Associated With Increased Risk of Hospitalization Adapted f rom Angaran P, Association of Left Ventricular Ejection Fraction with Mortality and Hospitalizations, Journal of theAmerican Society of Echocardiography, July 2020. Based on 27,323 patients evaluated over 4+ years follow - up; * EF e s t i m a t ed f or 30 2 1 . 8 1 . 6 1 . 4 1 . 2 1 0 . 8 0 . 6 0 . 4 0 . 2 0 < 25 % 25 - 3 5 36 - 4 5 46 - 5 5 H o s p i t a li z a t i o ns p e r 10 0 P Y I n d e x e d t o E F 40 % Ejection Fraction ~70% higher rate for E F 30 * vs 4 0 Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 44

2020 2030 1. Urbich, M., Globe, G., Pantiri, K. et al. A Systematic Review of Medical Costs Associated with Heart Failure in the USA (2014 - 2020). PharmacoEconomics 38, 1219 - 1236 (2020). https://doi.org/10.1007/s40273 - 020 - 00952 - 0 2. Heidenreich PA, Albert NM, Allen LA, Bluemke DA, Butler J, Fonarow GC, et al. Forecasting the impact of heart failure in the United States: a policy statement from the American Heart Association. Circ Heart Fail. 2013;6(3):606 - 19. https://doi.org/10.1161/HHF.0b013e318291329a. 3. Gaziano et al, AMA Cardiol. 2016;1(6):666 - 672. doi:10.1001/jamacardio.2016.1747 4. Givertz, M. M., Yang, M., Hess, G. P., Zhao, B., Rai, A., and Butler, J. (2021) Resource utilization and costs among patients with heart failure with reduced ejection fraction following a worsening heart failure event. ESC Heart Failure, 8: 1915 - 1923. https://doi.org/10.1002/ehf2.13155 5. Dunlay SM, Shah ND, Shi Q, Morlan B, VanHouten H, Long KH, Roger VL. Lifetime costs of medical care after heart failure diagnosis. Circ Cardiovasc Qual Outcomes. 2011 Jan 1;4(1):68 - 75. doi: 10.1161/CIRCOUTCOMES.110.957225. Epub 2010 Dec 7 High Cost Burden With Lion's Share Due to Hospitalizations O v e r n e x t d e c a d e , HF c o s t bu r d e n is expected to increase over half Mostly due to cycle of hospitalizations a n d r e - a d m i ss i on s Mean cost for each hospital stay of ~$17K 3 H F - a ss o c i a t e d c o s t s o f i n i t i a l h o s p i t a li z a t i o n a n d 1 2 m o n t h s f o ll o w i n g d i s c h a rg e ~ $35 K 4 O f t o t a l li f e t i m e H F c o s t b u r d e n , ~ 80 % d u e t o hospital stays 5 O u t p a t i e n t H F - r e l a t e d dr u g c os t s on l y ~ 2 - 3% of the total HF - related costs 4 U S H F B u r d e n ( $ B ) 69.7 2 Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 45 43.6 1

50% 46% 42% 39% Tremendous Burden on Patients and Caregivers 1 McHorney CA, et al. (2021) The impact of heart failure on patients and caregivers: A qualitative study. PLOS ONE 16(3): e0248240. https://doi.org/10.1371/journal.pone.0248240 https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0248240 . N = 90 (64 Patients, 26 Caregivers) 2 . D a t a o n F il e ( M a r k e t R e s e a r c h ) "This condition takes my life from me. I can't work anymore, walk my dog or go to dinner and movies with my daughters and husband." 2 Shortness of breath Fatigue/ t i r e dn e s s A n k l e / l e g swelling Trouble s l ee p i n g Reduced social interactions Ability to work 81% 77% 58% 50% M o s t F re q uen t l y R e po r t e d S y m p t o m s 1 S t r e ss e d fearful Recreational activities 67% 56% 44% 33% Reduced social interactions D i ff i c u l t y walking D e p r e ss i o n A n x i e t y I m p a c t o n C a r e g i v e r s I m p a c t o n Patients Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 46

U S G o - T o - M a r k et Strategy Andrew Callos, EVP, Chief Commercial Officer Jennifer Laux, VP, Cardiovascular Marketing Diann Potestio, VP, Global Value, Access & Distribution N o t F o r P r o m ot io n a l U s e , F o r I n v e s t o r s O n ly

Omecamtiv Mecarbil: GTM is Critical Step for Our Vision 2025 C o mm e r c i a l G o a l s a n d Aspirations Market Wh e r e t o f o c u s ? - Segmentation - Targeting - How to win? - Positioning - Value - Access - Medical - Internal How to organize? - B u il d v s B u y - Field Force - Digital - How to manage? - Forecasts - Budget - Investments - O m e c a m t i v M e c a r b i l G T M S t r at e gy S t r a t e g y D r i v e n b y K e y Ch o i c es G T M : Go - T o - Ma r k e t Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 48

GTM Is Based on Target Product Profile for Omecamtiv Mecarbil Demonstrated in patients with symptomatic chronic heart failure with EF 30 % (N= 5 , 842 ), 12 % (p< . 002 ) RRR in composite of CV death or HF events vs . placebo (translates into 3 . 8 % ARR, NNT= 27 ) Efficacy Omecamtiv mecarbil is the first myotrope, a selective cardiac myosin activator, that improves cardiac contractility without affecting cardiac myocyte calcium or myocardial oxygen consumption N o v e l M O A No difference in the change in systolic blood pressure vs placebo No change in potassium or creatinine levels during GALACTIC - HF E ff e c t s o n B P a n d R e n a l GALACTIC - HF. GALACTIC - HF ClinicalTrials.gov number, NCT02929329 Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 49

Our GTM Strategy: Gated Build of Core Capabilities S t r at e gic c h o ic e s a c r o s s e a c h G T M b l o c k S e q u e n ce , a n d g a t e b u il d - o u t ba s e d o n p r e - defined m il es t o n e s an d m e t ri c s to r e d u c e r i sk L e v e r a g e d ee p un d e r s t an d i n g of patients, H C P s , and institutional settings G e t a cc e ss t o ou r d r u g a s s oo n as possible E n g a g e a n d educate c a r d i o l o g i s t s i n the field S u p po r t p a t i en t s a n d c a r e g iv e r s Gated Build Insights Education Access Support Core capabilities to ensure success Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 50 World class Organization Commercial organization + Scalable organization, l e ve r a g i ng b e st p ra c t i c e s an d innovative solutions

Building a World Class Commercial Organization Driven by a relentless focus on our North Star: the patient Make strategic choices and investments enabled by data Enables scalability beyond first product launch Experienced leaders Deep f un c t i o n a l e x p e r ti s e Nimble d e c i s i o n making F o c u s e d o n o p e r a ti o n a l excellence Focused on highest value - add activities Full team of senior leaders in place who are driven by purpose Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 51

Gated Build Based on Key Milestones to Enable De - Risking NDA NDA Submission Acceptance 2021 2022 P D U F A Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 52 N o r e gr e t * i n v e s t m e n ts S e q u e n c e d i n v e s t m e n ts " A l l I n " P o s t - A pp r o v a l Investments Supply Leadership Data & Analytics A cc e s s & H E O R Campaign development Sales leadership Commercial operations Sales force Promotional spend Patient support * Given Cytokinetics pipeline, need to build these capabilities

Deep Understanding of the Patients, HCPs and Institutions Insights Education Access Support Worsening heart failure patient requiring more intensive treatment due to decreasing LVEF ( 30 % ), recent heart failure event ( 12 months), often with co - morbidities / tolerability issues limiting GDMT treatment Concentrated market with majority of patients seen by one third of cardiologists, clustered in large urban centers HF Clinics seeing worsening heart failure patients, and select hospitals where treatment changes are made during stay / recommended after discharge HCP Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 53 Institutions Patient

Patient High Unmet Need in Patients with Worsening Heart Failure Insights Education Access Support R e c e n t E v e n t HF Event* 12 months C a r d i a c F un c ti o n + LV E F 30 % W H F : W o r s e n i n g h e a r t f a i l ur e * HF Event: Urgent, unscheduled outpatient visit or hospitalization ** Due to renal impairment, low BP and/or hyperkalemia + / - Co - morbidities and/or tolerability** G D M T Li m it a ti o n s Worsening signs and symptoms of heart failure requiring intensification of treatment despite periods of stabilization on GDMT Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 54

Tremendous Burden of WHF on Patients and Caregivers "This condition takes my life from me " " I ca n ' t w a lk anymore, or walk my dog" "I dread having to be taken to the hospital again" " Despite all these meds , I still can't tend to my garden" "Caring for my loved one with HF is an exhausting full - time job " "I've become such a burden to my wife and daughters" Patient and caregiver focused campaign: educate, activate, and support Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 55

Multiple Ways to Initiate Omecamtiv Mecarbil G D M T m axe d o u t S y m p t o m s d e t e r i o r a t i n g Further decrease in EF T o l e r a b ili t y i s s u e s * P o t en t i a ll y li m i t e d b y c o - m o r b i d i t i e s / t o l e r a b il i t y Worsening H e a r t F a il u r e GDMT* Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 56 Add - on omecamtiv mecarbil R o u t i n e v i s i t t o c a r d i o l o gi s t or Heart Failure clinic Urgent , unscheduled outpatient visit Hospitalization due to heart failure event

HCP D ee p U nd e r s t a nd i n g o f H C P s M a n a gi n g W H F P a t i e n t s Insights Education Access Support High Prescribers A bo u t o n e t h i r d o f c a r diolo g i s t s s e e m a jo r i t y o f W H F patients Cardiologists A f f ili a t e d w i t h c a r di o l o g y p r a c t i c e , H F c li n i c , o r hospital Going beyond GDMT E a r l y a dop t e r s , i n c l u di n g hea r t f a il u r e / hea r t t r an s p l an t s p e c i a li s t s Geographic clusters M o s t l y i n u r b a n centers Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 57

S m a l l S u b s e t of C a r d i o l o g i s t s M a n a g e M a j o r i t y of Pa t i e n t s Symphony APLD (1/1/2019 - 12/31/2020); Physician Interviews; Analysis includes n = 25,510 cardiologists and n = 110,114 PCPs who see at least 1 HFrEF patient during the two - year market map period H F r E F P a t i en t C o n c en t r a t i o n i n C a r d i o l o g i s t s Distribution of High - Volume Cardiologists 0% 5 0 % 1 0 0% 0% 1 0 0% 50% % of Cardiologists Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 58 % of Patients Allows for more targeted field team approach, focusing on <10,000 HCPs

P o s i t i ve H C P R ea c t i o n s t o P r o du c t P r o f il e Proprietary market research Investigational products. Not approved as safe or effective for any indication High remaining unmet need in patients with worsening heart failure "I often run out of treatment options as my heart failure patients worsen" " I t ' s a g a m e c h a n g e r w h e n y o u don ' t have to worry as much about the kidney f un c t i o n , p o t a ss i u m o r b l oo d pr e ss ur e i n worsening patients." " I li k e t h at i t i s a m y o s i n a c t iv a t o r . I t is n o v e l a n d m o t i v a t i n g . I t h as a po s i t iv e rational and emotional impact." " W e n ee d dru g s t h at c an b e u s e d i n worsening patients with low EF. Those E ff ic a c y w i t h w o r s e d i s ea s e be n e f i t t h e m o s t . " S a f e ty M o A Positive Reactions From HCPs Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 59

Institutions Deep Understanding of the Institutional Settings Insights Education Access Support H i g h W H F p a t i en t vo l u m e , e a r l y a dop t e r s , c o m p r eh e n s i v e c a r e t e a m s 1. Symphony APLD (1/1/2019 - 12/31/2020); H F C li n i cs M a n a g i n g W H F p a t i en t s a n d m a k i n g a pp r op r i a t e t he r a p y a dj u s t m e n t s Select Hospitals Subset of institutions treat majority of heart failure patients 1 Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 60

Hospitals Increasingly Change Treatment Regimens I Q V I A 20 6 - 2018 , I Q V I A 202 0 % o f H F r E F P at i e nt s A drug in new c l a s s i s a dd e d A drug is replaced In same class T i t r a t i o n o f c u rr e n t treatment or no change 2016 - 201 8 2020 T r ea t m e n t C h a n g e s D u r i n g H o s p i t a l S t a y O v e r T i m e Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 61 Treatment changes increasingly made in hospitals, o n c e t h e p a t i e n t i s s t a b ili z e d , i n c l u d i n g a dd i n g d r u g s f r o m n e w c l a s s e s

Educating and Engaging HCPs Insights Education Access Support Despite COVID impact, in - person details continue to rise Personalized engagement approach via targeted sales force interactions and digital channels Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 62

Despite COVID, In - Person Details Continue to Rise 33% 50% 53% 54% 57% 61% 62% 66% 66% 66% Cardiology E n d o c r i n o l o g y Respiratory Gastroenterology Neurology N e ph r o l og y Dermatology Primary Care Psychiatry R h e u m a t o l og y Oncology In Person Details as % Baseline I Q V I A - C o v i d - 1 9 M a r k e t I m p a c t Baseline is the monthly average of Jan and Feb 2020 consisting of stable detail, patient visit and treatment volumes; Brandimpact HCP Network = ~3,600 unique HCPs incl. Oncology, Specialty and Primary Care. Specialty includes (not limited to) Allergy, Cardiology, Dermatology, Gastroenterology, Endocrinology, Neurology, Nephrology, Pulmonology, Psychiatry, Rheumatology and Urology In - person details continued to increase in all three groups in May. Only oncology in - person remains below 50% of baseline 8 82% 2% Biopharma In - Person Details vs. Baseline M a r c h 2020 J a nu a r y 2021 Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 63

Engagement Approach Allows Customizing and Broadening Targeted H F S p e c i a l i s t Targeted Community C a r d i o l o g i s t Broadening R e a c h B ey on d I n i t i a l T a r g e t D i g i t a l a ll o w s b r o a d e r r ea c h ~ ~ ill u s t r a t i ve ~ ~ Customizing engagement by different types of customers ~ ~ ill u s t r a t i ve ~ ~ F i e l d & Inside Digital Reimbursement MSLs Patient Online Account Reps Sales Engagement Specialists Services communities Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 64

Getting Access Insights Education Access Support Omecamtiv mecarbil may create significant value by reducing hospitalizations (and associated costs) 1 Given importance of Medicare Part D, we aim to minimize time to coverage given annual bid process To accelerate access, we are investing in highly experienced staff with existing relationships 1. Felker GM. ESC Heart Fail 2021 Oral Presentation. Data based on post hoc analyses. Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 65

Omecamtiv Mecarbil: Value Proposition I n H F r E F , p a ti e n t s w it h l o w e r e j e c ti o n f r a c ti o n s a r e h o s p it a liz e d m o r e o f t e n H o s p it a liz a ti o n r e d u c ti o n s s ee n in c li n i c a l t r i a l o f o m e c a m t i v m e c a r b i l Clinically meaningful and statistically significant hospitalization reductions seen among worsening HF p a t i en t s w i t h E F 30 2 1. Based on Solomon S, Influence of Ejection Fraction on Cardiovascular Outcomes in a Broad Spectrum of Heart Failure Patients, Circulation 2005 2. Felker GM. ESC Heart Fail 2021 Oral Presentation. Data based on post hoc analyses. I n H F r EF , e v e r y 1 0 poi n t s lo we r EF , i s p r ov e n t o d r iv e h i g he r e v en t s a n d r is k o f i n c r e a s e d h o s p i t a li z a t io n s 1 Our access activities may demonstrate economic value of omecamtiv mecarbil Partnering with key institutions to generate real world evidence of unmet needs in patients with lower ejection fractions Using HEOR and clinical results to demonstrate the economic impact and value Building Market Access team holding early discussions with payers Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 66

M e d i c a r e , B y F a r T he L a r g e s t P a y e r , W il l B e a K e y F o c us (CVS) (ESI) National Trends in Heart Failure Hospitalizations and Readmissions From 2010 to 2017 Agarwal, Fonarow, and Ziaeian; JAMA Cardiol, Feb 10, 2021 (Table 2 Payer Status); https://www.kff.org/medicare/issue - brief/10 - things - to - know - about - medicare - part - d - coverage - and - costs - in - 2019 IQVIA LAAD data. SGLT - 2 US Market Access Assessment, IQVIA. 1/7/2020 75% 50% Estimated Payer Mix Based On Other HF Brands Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 67

To Accelerate Access, Hiring Highly Experienced Staff Individually, 15 - 25 years of experience Collectively ~ 200 years of Payer / PBM Relationship Experience 250 years of Bio - Pharma Industry Experience Cytokinetics Account Director Customer Relationship Experience Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 68

Supporting Patients and Caregivers Insights Education Access Support Providing patient and caregiver education about disease and (post - approval) about product Evaluating innovative models for patient services, including a patient hub and digital approaches Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 69

We Put The Patient At The Center of Our GTM Strategy Patient A n a l y t i cs A f f o r d a b ili t y Access A d heren c e Caregiver HCP P h a r m a c y Payer Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 70

Evaluating Innovative Hub Models for Patient Services A n a l y t i cs A f f o r d a b ili t y Patient Access A d heren c e Caregiver HCP P h a r m a c y Payer M ix o f : H i g h - t o u c h s u pp o r t f o r p a t i e n t s a n d caregivers D i g i t a l a ss i s t a n t f o r p a t i e n t a n d H C P office staff Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 71

Evaluating Innovative Hub Models for Patient Services M ix o f : H i g h - t o u c h s u pp o r t f o r p a t i e n t s a n d caregivers D i g i t a l a ss i s t a n t f o r p a t i e n t a n d H C P office staff Free product ( t r i a l , s a m p l e s ) C o mm e r c i a l c o - p a y support P A P e n r o ll m e n t A n a ly t i cs A f f o r d a b ili t y P a t i e n t A cc e ss Adherence Caregiver H C P Pharmacy P a y e r R e i m b u r s e m e n t support P A s u ppo r t Appeals assistance D r i v e p r o c e s s efficiency P r e d i c t i v e a n a l y t i c s Address barriers On g o in g m o t i v a t i o n Support ecosystem connectivity Help patients start and stay on o m e ca m t iv m e ca r b il and eliminate barriers Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 72

Realizing The Promise of Omecamtiv Mecarbil Offering new hope for patients with worsening heart failure Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 73 Our Value Proposition Addresses large unmet need OM is an add - on therapy for worsening HF patients Reduces h o s p i t a li z a t i on cost burden 1 G a t e d Build Insights Education Access Support C o r e C a p a b il i t i e s W o r ld Class Organization Commercial Organization Our GTM Approach 1. Felker GM. ESC Heart Fail 2021 Oral Presentation. Data based on post hoc analyses.

Q&A To ask a question in the room, please raise your hand. To ask a question online, type it into the tab on the left. N o t F o r P r o m ot io n a l U s e , F o r I n v e s t o r s O n ly

B r e a k N o t F o r P r o m ot io n a l U s e , F o r I n v e s t o r s O n ly 2 - 5 m i nu t e s

HCM Landscape Andrew Callos, EVP, Chief Commercial Officer N o t F o r P r o m ot io n a l U s e , F o r I n v e s t o r s O n ly

I n U S, L a r ge H C M P o pu l a t i o n W i t h M a n y U nd i a g n o s e d N o w F u t u r e Currently ~280K diagnosed, ~190K oHCM symptomatic patients Estimated ~400 - 800K un - diagnosed patients 70 0 - 1 , 100 K 280K n H C M * 190K o H C M * Potential Undiagnosed Patients ~400 - 800K Diagnosed Patients Mav ~ a 28 su 0 c K cess H C M P r e v a l e n c e nHCM: non - obstructive HCM; oHCM: obstructive HCM CVRG market strategies heart failure 2Q 2021 and other sources on file Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 77

Multiple Activities Under Way to Increase HCM Diagnosis G e n e t i c T e st Companies G e n e t i c t e s t s Guidelines R a i s e d A wa r e n e ss F r o m N e w T r e a t m e n t s Academia and industry partnering to support early HCM detection (incl AI - based) and monitoring Genetic testing companies raising awareness and driving testing for high - risk patients Professional organizations and Academia revising HCM treatment guidelines given recent development in HCM New treatment options and pharmaceutical companies starting to invest and educate more Early Detection HCM market expected to grow significantly Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 78 CVRG market strategies heart failure 2Q 2021 and other sources on file

U n m e t Need Be t a - B lo c k e r CCB D i s o p y r a m i de a nd / o r S e p t a l R e d u c t i o n The Unmet Treatment Need in oHCM B e t a - B l o c ke r CCB Disopyramide 30% NYHA C l a s s I 40% NYHA C l a s s II 30% NYHA C l a s s I I I / IV HCM with Outflow Obstruction ( 3 0 mm H g a t r e s t / e x e r c i s e ) Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 79 1. Maron BJ. Clinical Course and Management of Hypertrophic Cardiomyopathy. The New England Journal of Medicine. 2018 Aug;379(7):655 - 668. DOI: 10.1056/nejmra1710575. PMID: 30110588. 2. Maron BJ, Casey SA, Poliac LC, Gohman TE, Almquist AK, Aeppli DM. Clinical Course of Hypertrophic Cardiomyopathy in a Regional United States Cohort. JAMA. 1999;281(7):650 - 655. doi:10.1001/jama.281.7.650 3. Zaiser E, Sehnert AJ, Duenas A, Saberi S, Brookes E, Reaney M. Patient experiences with hypertrophic cardiomyopathy: a conceptual model of symptoms and impacts on quality of life. J Patient Rep Outcomes . 2020;4(1):102. Published 2020 Dec 1. doi:10.1186/s41687 - 020 - 00269 - 8

Pharmacological C u r r e nt S t and a r d o f C a r e - B e t a B l o cke r s - C a l c i u m C h a n n e l B l o c ke r s F o c us o n s y m p t o m r e li e f R es u l t s a r e o ft e n i na d e q u a te I n d i r ec t m ec ha n i s m s o f a c t io n S y s t e m i c s i de e ff ec t s Current oHCM Treatments Have Significant Limitations C u rr e n t S O C d o e s n o t a dd r e s s und e r l y i n g d i s e a s e Surgical S e p t a l r e d u c t i o n t h e r a p y c a n r e d u c e se p t al t h i ck n es s a n d o ff e r r e li e ve S u r g i c a l m ye c t o m y i s i n v as i ve a n d c a n c a r r y r i s k N o t a l wa y s a p e r m a n e n t s o l u t i o n Surgery ~10 - 20% Pharma ~80 - 90% o H C M T r e at m e n t O p ti o n s S O C : S t anda r d o f c a r e Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 80

Medical A nnu a l m e di c a l c o s t s m o r e t ha n do u bl e d f o ll o w i n g d i a gn o s i s Cost Per Patient ($K) 20 Total HCM - related costs increased by ~4x one year after diagnosis Also, Significant Cost Burden With Current Treatments 6 P r e Dx P o s t Dx B u t z n e r e t a l . 202 1 Surgical H i g h s u r g e r y c o s t s as w e l l as c o s t s o f m e di c a l a n d p h a r m a c y c o s t s po s t - p r o c e d u r e 92 Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 81 45 54 Surgery Cost 12 - Mo Post S u r ge r y M e d / R x Surgery Cost 12 - Mo Post S u r ge r y M e d / R x Cost Per Patient ($K) 120 Septal Myectomy Alcohol Septal Ablation

Remaining Areas of Unmet Need in oHCM Drugs that can i m p a c t l on g t e r m complications Drugs that p r e v e n t H C M i n G e n e + v e p a t i e n t s Drugs that work i n m o r e s e v e r e patients Drugs that p r o v ide r eve r s e r e m o d e l b e n e f i t Drugs that i m p r ov e f un c t i o n and exercise capacity Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 82

R e du c e ti m e t o o p ti m a l d o s e W i den t h e r a p e u ti c w i n d o w F e w e r d o s e a d j u s t m e n ts N o p l a s m a m o n it o r i n g A f i c a mt e n : A N e xt G e n e r a t i o n T h e r a p y A tt r i b u t e s m a y t r a n s lat e i nto A c c e l e r a t e d S y m p t o m R e li e f D o se Op t i m i z a t i o n R a p i d R e v e r s i b ili t y K e y A tt r i b u t e s Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 83

Key Components of Aspirational Target Profile Functional Improvement: Improved exercise capacity Symptom Improvement: One or two class improvement in NYHA class Q u a li t y o f L i f e : K CC Q i m p r o v e m e n t Efficacy M i n i m a l d r u g - d r u g i n t e r a c t i o n s Maintain LVEF: >50% on vast majority of patients R e v e r s i bili t y : Q u i c k l y r e v e r s i b l e w i th t i tr a t i o n do wn S a f e t y a n d T o l e r a b il i ty Titration: Time to optimal dose, ~2 week titration intervals using echocardiography No monitoring of plasma concentrations Dosing Product not FDA approved, aspirational profile dependent on phase 3 data Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 84

Three Key Sources of Patients for Aficamten 2022 A f i c a m t e n Launch Undiagnosed Patients F u t u r e Diagnosed Patients Mava success ~~ ill u s t r a t i v e ~~ O t h e r t r eat m e n ts Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 85 a f i c a m t e n Mava Switch 700 - 1,100K 100 - 280K K e y s o u r c e s o f p a ti e n ts N e w l y d i ag no s e d T h e r a p y f a il u r e s E xc l u d e d p a t i e n t s

Aficamten: Value Proposition Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 86 Profile addresses all oHCM patients regardless of severity of disease or risk No anticipated contraindications and minimal drug interactions Addresses largely untapped market, potential of over 400K undiagnosed oHCM patients Second generation treatment for newly diagnosed, therapy failures and excluded patients

Potential Next - In - Class Therapy Steve Heitner, M.D., Senior Medical Director, Clinical Research Cardiovascular A f i c a m t e n : N o t F o r P r o m ot io n a l U s e , F o r I n v e s t o r s O n ly

A f i c a m t e n : L e v e r a g i n g P h a r m a co l o g y for C l i n i c a l P r a c t i ce P r e c i s e D o si n g Simplicity of Use Rapid Reversibility Symptom relief as early as within 2 weeks initiation and dose adjustment possible bi w ee k l y i f indi c a t e d Echo guided dose titration a llo w s bo t h do s e i n c r ea s e s and decreases at the patient visit No off - target effects and use in combination with - blockers, CCB, Disopyramide, and/or Ranolazine Washout of pharmacodynamic e ff e c t w i t h i n 2 w ee k s Rapid Onset Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 88

Phase 2 Clinical Trial Design Two sequential dose - finding cohorts (with third cohort assessing patients on disopyramide ) I P D o s i n g Echocardiogram D o s e 1 D o s e 2 D o s e 3 P a t i e n t s w i t h s y m p t o m a t i c o H C M , and resting or provoked LVOT gradient 50 mmHg S t u d y V i s i t s S c r ee n W - 1 D1 W2 W4 W6 W9 W 1 0 W 1 2 W 1 4 Screening Randomizatio n A f i c a m t e n + S o C Placebo + SoC E nd o f S t udy 1 Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 89 2 Dose 1 Dose 2 Dose 3 C o h o r t 1 5 mg 1 0 mg 1 5 mg C o h o r t 2 1 0 mg 2 0 mg 3 0 mg

Patient Enrollment and Dosing 41 Total Enrolled Patients Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 90 Final Dose Achieved (N) 5 mg 10 mg 15 mg 20 mg 30 mg N = 14 Cohort 1 4 5 5 N = 14 Cohort 2 9 4 1

Characteristic P la c e b o (n = 13) Aficamten (n = 28) A g e ( Y e ar s ) , M e a n ( S D ) [ R a n g e ] 57.2 (9.6) [36,69] 56.6 (13.6) [33,78] < 65 Years 10 (77%) 17 (61%) S e x , n ( % ) Female 8 (62%) 15 (54%) Race = White , n (%) 12 (92%) 28 (100%) NYHA Class , n (%) C l a s s I I 11 (85%) 17 (61%) C l a s s II I 2 (15%) 11 (39%) M a x i m a l L V W al l T h i c k n e s s ( mm ) M e a n ( S D ) 16 (3) 17 (3) L V E F* a t S c r ee n i n g ( % ) , M e a n ( S D ) 73.6 (5.9) 71.7 (8.0) LVOT - G*, Rest at Screening (mmHg), Mean (SD) 70.0 (28.0) 61.1 (29.8) LVOT - G*, Valsalva at Screening (mmHg), Mean (SD) 93.3 (27.2) 89.3 (31.5) * S i t e - r e a d e c h o c a r d i o g r a m Baseline Characteristics Maron M, Abraham T, Masri A, et al. "REDWOOD - HCM: A Randomized, Double - blind, Placebo - controlled, Dose - finding Trial of the Cardiac Myosin Inhibitor, Aficamten , In Obstructive Hypertrophic Cardiomyopathy" Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 91

High Response Rates on Treatment with Aficamten Responder Definition: R e s t i n g L V O T - G < 3 0 mm H g a n d po s t - V a l s a l v a L V O T - G < 5 0 mm H g a t W ee k 1 0 1 / 1 3 11 / 1 4 13 / 1 4 Responder # / Total # P l a c e b o Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 92 Aficamten : C1 0 20 40 60 80 100 % T o t al N o t R e s p o nd e r Responder 21.4 % 7.1 % 7.7 % 78.6 % 92.9 % 92.3 % Aficamten : C2 M a r o n M , A br a h a m T , M a s r i A , e t a l . " RE D W OO D - H C M : A R a n d o m i z e d , D o ub l e - b li n d , P l a c e b o - c o n t r o ll e d , D o s e - f i nd i n g T r i a l o f t h e C a r d i a c M y o s i n I nh i b i t o r , A f i c a m t e n , I n O b s t r u c t i v e H y p e r t r o p h i c C a r d i o m y o p a th y "

REDWOOD - HCM: Efficacy Resting Left Ventricular Outflow Tract Gradient (LVOT - G) M e a n S E M R e s t i n g L V O T - G ( mm H g ) Baseline W ee k 2 W ee k 4 W ee k 6 W ee k 1 0 P l ac e bo ( n = 1 3 ) 52.1 45.0 47.1 49.0 44.0 C o h o r t 1 ( n = 14 ) 53.8 24.3 27.3 13.9 13.4 p - v a l ue v s p l a c e bo - 0.007 0.025 <0.0001 0.0003 C o h o r t 2 ( n = 14 ) 58.2 15.5 16.1 10.9 15.1 p - v a l ue v s p l a c e bo - 0.0002 0.0006 <0.0001 0.0004 W eek s 0 20 40 60 R e s t i n g L V O T - G 80 mm H g C o m b i n e d P l a c e bo A fi c a m t e n : C oh o r t 1 A fi c a m t e n : C o h o r t 2 8 1 0 12 * ** ** ** m e a n S E M 0 2 4 6 *** *** ** ** Washout Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 93 Treatment LVOT - G 30 mmHg * P < 0 . 05 * * P < 0 . 001 ** * P < 0 . 0001 P - v a l u e s v e r s u s P l a c e b o M a r o n M , A br a h a m T , M a s r i A , e t a l . " RE D W OO D - H C M : A R a n d o m i z e d , D o ub l e - b li n d , P l a c e b o - c o n t r o ll e d , D o s e - f i nd i n g T r i a l o f t h e C a r d i a c M y o s i n I nh i b i t o r , A f i c a m t e n , I n O b s t r u c t i v e H y p e r t r o p h i c C a r d i o m y o p a th y "

REDWOOD - HCM: Efficacy Va l s a l v a LV O T - G M e a n S E M V a l s a l v a L V O T - G ( mm H g ) Baseline W ee k 2 W ee k 4 W ee k 6 W ee k 1 0 P l ac e bo ( n = 1 3 ) 84.6 71.3 71.3 73.4 76 C o h o r t 1 ( n = 14 ) 74.4 51.3 46.1 37.1 38.1 p - v a l ue v s p l a c e bo - 0.097 0.038 0.0003 0.001 C o h o r t 2 ( n = 14 ) 82.3 32.3 31.5 30.3 29.8 p - v a l ue v s p l ac e bo - 0.0005 0.0005 <0.0001 <0.0001 W eek s 0 20 40 60 V a l s a lv a L V O T - G 100 mean SEM 0 2 4 6 8 1 0 12 mm H g 80 C o m b i n e d P l a c e bo A fi c a m t e n : C oh o r t 1 A fi c a m t e n : C o h o r t 2 ** ** * ** *** *** ** LVOT - G 50 mmHg * P < 0 .05 * * P < 0 .001 ** * P < 0 . 0 0 01 P - v a l u e s v e r s u s P l a c e b o Washout Treatment M a r o n M , A br a h a m T , M a s r i A , e t a l . " RE D W OO D - H C M : A R a n d o m i z e d , D o ub l e - b li n d , P l a c e b o - c o n t r o ll e d , D o s e - f i nd i n g T r i a l o f t h e C a r d i a c M y o s i n I nh i b i t o r , A f i c a m t e n , I n O b s t r u c t i v e H y p e r t r o p h i c C a r d i o m y o p a th y " Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 94

REDWOOD - HCM: Efficacy Changes in Left Ventricular Ejection Fraction over Study Period C o m b i n e d P l a c e b o ( N = 13 ) A f i c a m t e n : C oh o r t 1 ( N = 14 ) A f i c a m t e n : C oh o r t 2 ( N = 1 4 ) W eek s Washout Treatment 40 2 4 6 8 1 0 12 * * * * * * * D o s e r e d u c t io n t h r e s h old Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 95 * P < 0 .05 50 60 70 80 L V E F ( % ) Maron M, Abraham T, Masri A, et al. "REDWOOD - HCM: A Randomized, Double - blind, Placebo - controlled, Dose - finding Trial of the Cardiac Myosin Inhibitor, Aficamten , In Obstructive Hypertrophic Cardiomyopathy"

Change from Baseline in NT - proBNP & NYHA Class C h a n g e f r o m B a s e li n e N T - p r o B N P t o W ee k 1 0 * P = 0 . 00 3 fo r P ool e d C o h o r t 1 & 2 v s . P l a c e b o 0 - 200 - 400 - 600 - 800 - 1000 NTproBNP (pg/mL) * P l a c e b o A f i ca m t en : Cohort 1 A f i ca m t en : Cohort 2 Combined Placebo (N=13) A f ica m t e n : C o h o r t 1 ( N = 14 ) A f ica m t e n : C o h o r t 2 ( N = 14 ) Improvement in Heart Failure Symptoms (NYHA Class) 69% (n=9) 57% (n=8) 36% (n=5) 31% (n=4) 43% (n=6) 64% (n=9) 100 80 60 40 20 0 % Total P l a c e b o A f i ca m t en : Cohort 1 A f i ca m t en : Cohort 2 C o h o r t 1 v s P l a c e bo : p > 0 . 1 C o h o r t 2 v s P l a c e b o : p = 0 . 0 8 Week 10 Responder Definition: Improvement in NYHA Class 1 No Improvement in NYHA Class 1 NYHA Class Improvement Maron M, Abraham T, Masri A, et al. "REDWOOD - HCM: A Randomized, Double - blind, Placebo - controlled, Dose - finding Trial of the Cardiac Myosin Inhibitor, Aficamten , In Obstructive Hypertrophic Cardiomyopathy" Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 96

REDWOOD - HCM: Safety Data No patients met the "stopping criteria" of LVEF < 40% N o t r e a t m en t i n t e rr u p t ion s o r di s c o n t i nu a t io n s T r e a t m en t E m e r g e n t A dv e r s e E v en t s P l a c e bo 85 % o f pa r t i c i pa n t s A f i c a m t e n 88 % o f pa r t i c i pa n t s L V E F < 50 % ( C o h o r t 2 o n ly ) 1 patient (baseline EF = 58%) underwent per - protocol dose reduction at Week 4 and had LVEF return above 50% (max dose 20 mg) 1 patient (baseline EF = 70%) had LVEF 49.3% at Week 10 (max dose 20 mg; no dose changes ) and LVEF returned to b a se li n e a t t h e e n d o f s t u dy ( W ee k 12 ) 2 S A E s r e po r t e d i n C o h o r t 1 a n d n o n e i n C o h o r t 2 Stress Cardiomyopathy: 55 - year - old female assigned to P l a c e bo , w i th a s s o c i a t e d c a r d i o g e n i c s ho c k a f t e r IP d i sc on t i n u a t i o n a t e n d o f tr e a t m e n t ( W ee k 10 ) . Back Pain: 50 - year - old male assigned to aficamten (dose 5 mg at the time of SAE, and max dose 15 mg) visited Emergency Room for exacerbation of preexisting musculoskeletal back pain. N o S A E s r e po r t e d t h a t r e s u l t e d i n e a r l y t e r m i n a t io n N o t r e a t m en t - r e l a te d s e r io u s a dv e r s e e v ent s No imbalance in adverse events between aficamten a n d p l a c e b o t r ea t e d a r m s Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 97 Maron M, Abraham T, Masri A, et al. "REDWOOD - HCM: A Randomized, Double - blind, Placebo - controlled, Dose - finding Trial of the Cardiac Myosin Inhibitor, Aficamten , In Obstructive Hypertrophic Cardiomyopathy"

REDWOOD - HCM: Cohort 3 Dose 1 Dose 2 Dose 3 C o h o r t 3 5 mg 1 0 mg 1 5 mg A m b u l a t o r y C a r d i a c M o n i t o r i n g E c h o c a r d io g r a m D o s e t i t r a t io n P a t i e n t s w i t h s y m p t o m a t i c o H C M , and resting or provoked LVOT gradient 50 mmHg S t u d y V i s i t s S c r ee n W - 1* D1 W2 W 8 * W 9 * W 1 0 W 14 * Screening A f i c a m t e n + S o C A N D d i s o p y r a m i d e E nd o f S t udy W 6 * * W4 * T e l ephon e v i s i t s ** P a t i en t c a n on l y b e do w n - t i t r a t e d a t W ee k 6 W 1 2 E n r o ll m e n t c o m p l e t e i n C oho r t 3 Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 98

Open Label Extension Trial Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 99 REDWOOD - HCM OLE open for eligible patients who completed REDWOOD - HCM P r i m a r y e ndp o i n t: i n c i d e n c e of A E s & L V E F < 5 0 Secondary endpoints : measures of long - term effects of aficamten on LVOT - G ; assessments of steady - state pharmacokinetics . Cardiac MRI sub - study to assess changes in cardiac morphology, function and fibrosis I nd ivi d u a lly o p ti m i z e d d o s e s t a r ts a t l o w e s t d o s e in prespecified range with echo - guided dose titration Initial dose and highest target dose informed by interim analyses from REDWOOD - HCM O L E : E sc a l a t i n g d o s e s b a s e d o n e c h o - g u i d e d d o se t i t r a t i o n

W e l l t o l e r a t e d d o s e w i t h d e s i r e d P D e ff e c t s o H C M p a t i e n t s P l a c e b o C o n t r o ll e d E c h o c a r d i o g r ap h y E nd po i n t s o H C M p a t i e n t s E x e r c i s e E n d p o i n t ( p e a k V O 2) E x t e n s io n s t u d y L o n g - t e r m s a f e t y & e ff i c a c y S AD & M AD Healthy Volunteers P r oo f o f a c t i v i t y i n n H C M p t s P i v o t a l s t udy i n n H C M I N D F i l e d N D A Aficamten : Clinical Development Plan for HCM Engaging regulatory authorities to inform Phase 3 I mp r o v e d L V O T g r a d i e nt N D A : P o t e n t i a l f o r a pp r o v a l b a s e d on a s i n g l e P h3 s t udy w i t h a n e x e r c i s e e ndp o i nt P h a s e 1 S a f e t y , PK & P D P h a s e 2 P r oo f o f C o n c e p t , D o s e F i nd i ng P h a s e 3 P i v o t a l S t ud i es Type C and end - of - phase 2 meetings with FDA occurred in Q3; Plans underway to start Phase 3 trial in Q4 Charting the Commercial Course : Analyst & Investor Day 2021 N o t fo r P r o m ot i o n a l U s e , F o r I n v e s t o r s O n l y 100