Deep Insights,Impactful Medicines May 2021 Disclaimers Various statements in this presentation concerning the future expectations, plans and prospects of Scholar Rock, Inc. ("Scholar Rock"), including without limitation,

Deep Insights,Impactful Medicines May 2021

Disclaimers Various statements in this presentation concerning the future expectations, plans and

prospects of Scholar Rock, Inc. ("Scholar Rock"), including without limitation, Scholar Rock's expectations regarding its strategy, its product candidate selection and development timing, including timing for the initiation of and reporting

results from its clinical trials for its product candidates, its disease indication selection and timing for such selection, the ability of apitegromab (SRK-015) to affect the treatment of patients suffering from Spinal Muscular Atrophy (SMA)

either as a monotherapy or in conjunction with the current standard of care, and the ability of SRK-181 to affect the treatment of cancer patients in a manner consistent with preclinical data constitute forward-looking statements for the

purposes of the safe harbor provisions under The Private Securities Litigation Reform Act of 1995. The use of words such as "may," "might," "will," "should," "expect," "plan," "anticipate," "believe," "estimate," "target," "project," "intend,"

"future," "potential," or "continue," and other similar expressions are intended to identify such forward-looking statements. Actual results may differ materially from those indicated by these forward-looking statements as a result of various

important factors, including, without limitation, preclinical and clinical data, including the 12-month top-line results from the Phase 2 trial of apitegromab, are not predictive of, are inconsistent with, or more favorable than, data generated

from future clinical trials of the same product candidate, including the planned Phase 3 trial of apitegromab in SMA, Scholar Rock's ability to provide the financial support, resources and expertise necessary to identify and develop product

candidates on the expected timeline, information provided or decisions made by regulatory authorities differ from the company's expectations, competition from third parties that are developing products for similar uses, Scholar Rock's ability

to identify and develop multiple product candidates on the expected timeline, the impacts of the COVID-19 pandemic, Scholar Rock's ability to obtain, maintain and protect its intellectual property, Scholar Rock's dependence on third parties for

development and manufacture of product candidates including to supply any clinical trials, and Scholar Rock's ability to manage expenses and to obtain additional funding when needed to support its business activities and establish and maintain

strategic business alliances and new business initiatives as well as those risks more fully discussed in the section entitled "Risk Factors" in the Quarterly Report on Form 10-Q for the quarter ended March 31, 2021, which is on file with

the Securities and Exchange Commission, as well as discussions of potential risks, uncertainties, and other important factors in Scholar Rock's subsequent filings with the Securities and Exchange Commission. Any forward-looking statements

represent Scholar Rock's views only as of today and should not be relied upon as representing its views as of any subsequent date. Scholar Rock explicitly disclaims any obligation to update any forward-looking statements unless required by law.

Gilead fibrosis-focused TGF collaboration DRAGON Part A: dose escalation and continued

follow-up ApitegromabSpinal Muscular Atrophy (SMA) SRK-181 Immuno-Oncology and Oncology Preclinical/ Platform TOPAZ 12M topline data Planned apitegromab Phase 3 program in SMA by year-end 2021: Potential for Another Transformative

Year TOPAZ extension Continue to discover and advance preclinical programs Multiple opportunities for additional myostatin-related indications beyond SMA and muscular dystrophies Multiple additional opportunities: 1) SRK-181 in

oncology; 2) latent TGF 1 immune cell in IO; 3) latent TGF 1 immune cell in oncology Gilead Fibrosis collaboration 2022 and Beyond 2021 Q3 Q4 Q2 Latent TGF 1 Immune Cell Immuno-Oncology and Oncology 3 DRAGON Part B to initiate

mid-year: multiple tumor typesMelanomaNSCLCUrothelial CarcinomaOther Solid Tumor Types ApitegromabOther Indications Multiple opportunities in muscular dystrophies, including Becker Muscular Dystrophy

4 Bringing a Revolutionary Approach to Highly Sought-After Growth Factors Implicated in Devastating

Diseases Scholar Rock's Target Growth Factor Precursor (Latent Form) Scholar Rock's R&D PlatformTransform Medical Practice Pursue important targets with well-validated biology but are difficult to drugApply revolutionary approach to

tough targetsLeverage deep insights into structure and function Engineer antibodies to deliver differentiated therapeutic profiles(i.e. exquisite selectivity) TOPAZ demonstrated the therapeutic potential of inhibiting the latent forms of

Apitegromab: Transformative Potential Demonstrated in TOPAZ Phase 2 Trial for Patients with Type 2 and 3

6 Apitegromab Positioned to be Next Potential Transformative Therapy for Patients Suffering with

SMA Spinal Muscular Atrophy (SMA) remains a devastating and debilitating illness despite the availability of SMN upregulatorsTo improve motor function, a muscle-directed approach like apitegromab is needed to complement the disease stabilizing

effects of SMN upregulatorsApitegromab demonstrated transformative potential in SMA through the TOPAZ Phase 2 trial, especially in non-ambulatory Type 2 and 3 patientsPatients 2-6 years of age: +7.1-point increase in HFMSE and 63% attained a

3-point increase with 20 mg/kg dosePatients 8-19 years of age: +1.2-point* increase in HFMSE and 31% attained a 3-point increaseNon-ambulatory Type 2 and 3 patients represent ~2/3 of overall populationTOPAZ results offer exciting path forward

for investigating apitegromab in a rational, targeted, and efficient Phase 3 trial in non-ambulatory Type 2 and 3 patients *Per-protocol: excludes patient with concomitant exposure to an acetylcholinesterase inhibitor not permitted per the

7 Spinal Muscular Atrophy Overview Significant, progressive motor function impairment, many lose

ambulation Infantile onset; unable to sit up independently Severe, progressive disabilities and Unable to walk independently Global disease with 30,000-35,000 affected in U.S. and Europe alone TOPAZ* 12-month results demonstrated

transformative efficacy in non-ambulatory Type 2 and 3 patients Represents ~2/3 of overall patient population Motor neuron impairment and loss due to SMN genetic deficiency, leading to muscle atrophy and weakness *TOPAZ Phase 2 trial

evaluated patients with Type 2 and 3 SMA (did not include Type 1)

Apitegromab: Muscle-Directed Therapy Aimed at Complementing SMN Upregulators 8 Adapted from images

courtesy of the SMA Foundation Myostatin is a negative regulator of skeletal muscle growthApitegromab is a fully human, mAb that specifically binds to proforms of myostatin and inhibits myostatin activation Apitegromab is a muscle-directed

approach aimed at improving motor function Apitegromab SMN upregulators prevent further degeneration of motor neurons...but do not directly address muscle atrophy Motor neurondegeneration Muscle fiber atrophy

9 Stage is Set for New Treatment Era: Muscle-Directed Therapy + SMN Upregulators Phase 3Trial

Design Indication MarketPenetration *As of 1Q21 financial update on 4/22/21; includes patients treated worldwide in post-marketing setting, expanded access program, and clinical trials.**As of 1Q21 financial update on 4/21/21; includes

patients treated worldwide between clinical trials, commercial, and compassionate use program.***As of 1Q21 financial update on 4/27/21; commercially, via managed access programs and in clinical trials Persistent Need Non-ambulatory Type

2/32-12 years of agePrimary endpoint: Mean change from baseline in HFMSE at 15 months >11,000* patients treated WW$2+ billion in revenues (LTM) 1,200*** patients treated WW$1.1 billion in revenues (LTM) ~3,000** patients treated

WW~CHF135 million in revenues (LTM) Type 1, 2, and 3 SMA in pediatric and adult patients Type 1, 2, 3 SMA in patients 2 months of age and older Approved for SMA less than 2 years of age Non-ambulatory Type 2/3 2-25 years of agePrimary

endpoint: Mean change from baseline in MFM-32 at 12 months Infantile-onset Type 1<6 months of agePrimary endpoints: Ability to sit independently and event-free survival Major functional deficits remainIncreases in MFM-32 primarily limited

to youngest patientsHFMSE effects not as pronounced Limited data and eligibility for use beyond very young patients Major functional deficits remainHFMSE improvements only in younger patients and rapidly plateaus

Patients Continue to Experience Major Functional Deficits Despite Availability of Multiple SMN

Upregulator Therapies 10 Source: Darras, B., et.al. Nusinersen in later-onset spinal muscular atrophy. Neurology. May 2019; 92 (21) e2492-e2506.This third-party information is provided for background only and is not intended to convey or

imply a comparison to the TOPAZ clinical trial results. Mean improvement in HFMSE score experienced by patients withnon-ambulatory Type 2/3 SMA in the Phase 3 CHERISH clinical trial of nusinersen HFMSE increase from nusinersen HFMSE Score

at Month 15 Total Possible HFMSE Score of 66 Treated patients still experience major functional deficits TOPAZ Therapeutic Hypothesis: Apitegromab may improve outcomes in patients with SMA on chronic maintenance nusinersen.

Non-Ambulatory Type 2/3 SMA: Nusinersen Offers HFMSE Increases Primarily in First Year of

Treatment 11 "Longer-term treatment with nusinersen: results in later-onset spinal muscular atrophy from the SHINE study" P.257, World Muscle Society Congress 2020This third-party information is provided for background only and is not

intended to convey or imply a comparison to the TOPAZ clinical trial results. Initial treatmentCHERISH Chronic maintenance phaseSHINE Most nusinersen-treated patients in CHERISH were <5 years at therapy initiation +3.9-points Mean (+

SE) Change in HFMSETotal Score From Baseline Analysis Visit, d 1 92 169 253 350 450 690 930 1170 1410 1650 -1-2-3-4 8765 43210 Nusinersen CHERISH trial showed mean HFMSE increase of +3.9 points in first 15 monthsImprovement largely

observed in younger patientsMajority of older children (initiate treatment >5 years of age) do not improve +3.9-points

Plateauing of Nusinersen Effect Observed Post Initial 15 Months of Treatment in Non-Ambulatory Type 2/3

SMA 12 "Longer-term treatment with nusinersen: results in later-onset spinal muscular atrophy from the SHINE study" P.257, World Muscle Society Congress 2020This third-party information is provided for background only and is not intended to

convey or imply a comparison to the TOPAZ clinical trial results. Most nusinersen-treated patients in CHERISH were <5 years at therapy initiation Mean (+ SE) Change in HFMSETotal Score From Baseline Analysis Visit, days 1 92 169 253 350

450 690 930 1170 1410 1650 -1-2-3-4 8765 43210 Nusinersen observed plateauing of improvement during chronic maintenance phase <1-point increase in HFMSE after first 15 months of treatment +3.9-points +4.6-points Unmet Need for

Motor Function Gains Initial treatmentCHERISH Chronic maintenance phaseSHINE

Apitegromab Phase 2 Trial Design 13 Patients with Type 2 and 3 SMA Ambulatory Type 3 patients

(ages 5-21)Apitegromab 20 mg/kg IV Q4W monotherapy or with chronic nusinersen maintenance Key objectives: RHS and Safety at 12 months Non-ambulatory Type 2 patients (ages 2) on chronic maintenance nusinersen (initiated <5 years of

age)Apitegromab 2 mg/kg and 20 mg/kg IV Q4W + nusinersen Key objectives: HFMSE and safety at 12 months Non-ambulatory Type 2/3 patients (ages 5-21) on chronic maintenance nusinersen (initiated 5 years of age) Apitegromab 20 mg/kg IV Q4W +

nusinersen Key objectives: HFMSE and safety at 12 months 57 patients* completed 12-month TOPAZ trial All Elected to Opt Into Extension Period Patients on background SMN therapy were in chronic maintenance phase of nusinersen (~5

mean maintenance doses at baseline) *Excludes one patient from Cohort 1 that discontinued from the trial

Baseline CharacteristicsNusinersen-treated patients well into chronic maintenance

phase 14 Non-Ambulatory,Ages 2-6 Non-Ambulatory,Ages 8-19 Ambulatory 20 mg/kg +nusinersen 2 mg/kg +nusinersen Pooled 20 mg/kg +nusinersen 20 mg/kgmonotherapy 20 mg/kg +nusinersen Pooled N

10 10 20 15 11 12 23 Mean age (min, max) 3.8 (2, 6) 4.1 (2, 6) 4.0 (2, 6) 11.7 (8, 19) 12.1 (7, 19) 13.1 (7, 21) 12.6 (7, 21) Mean RHS score (min, max) 47.6 (26, 63) 51.3 (43, 62) 49.6 (26, 63) Mean HFMSE score

(min, max) 23.5 (14, 42) 26.1 (12, 44) 24.8 (12, 44) 22.7 (13, 39) Mean # of nusinersen maintenance doses (min, max) 5.4 (3, 8) 5.5 (2, 9) 5.5 (2, 9) 5.1 (2, 9) N/A 5.6 (2, 8) N/A SMN2 Gene Copy* (#, %) 2 1

(10%) 1 (10%) 2 (10%) 1 (9%) 0 (0%) 1 (4%) 3 8 (80%) 8 (80%) 16 (80%) 11 (73%) 4 (36%) 9 (75%) 13 (57%) 4 0 (0%) 1 (10%) 1 (5%) 2 (13%) 4 (36%) 1 (8%) 5 (22%) Discontinuation(s) 0 0 0 0 0 1** 1** *Data not

available for all patients**Patient who discontinued study for reasons unrelated to study drugHFMSE=Hammersmith Functional Motor Scale Expanded; RHS=Revised Hammersmith Scale Data on file. Scholar Rock, Inc. Cambridge, MA

Non-Ambulatory Cohort (Ages 2-6): Sizable HFMSE Increases of Up to 20-points 15 Non-Ambulatory Type 2

SMA(Intent-to-Treat Population) Apitegromab 20 mg/kg + nusinersen (n=8) Apitegromab 2 mg/kg + nusinersen (n=9) Pooled (n=17) Mean change from baseline in HFMSE (95% CI) +7.1 (1.8, 12.5) +5.3 (-1.5, 12.2) +6.2 (2.2, 10.1) # (%) patients

achieving 1-pt increase in HFMSE 7/8 (88%) 7/9 (78%) 14/17 (82%) # (%) patients achieving 3-pt increase in HFMSE 5/8 (63%) 5/9 (56%) 10/17 (59%) # (%) patients achieving 5-pt increase in HFMSE 5/8 (63%) 5/9 (56%) 10/17 (59%) 35%

(6/17) with >10-point increase in HFMSEUp to 20-point increases in HFMSE observedSizable, dose-dependent increases in HFMSE observed in patients already on chronic maintenance nusinersenDurable and continuous improvements observed through

12-monthsCHERISH and SHINE nusinersen studies suggest substantial HFMSE increases do not occur in younger patients following first year of treatment Data on file. Scholar Rock, Inc. Cambridge, MA

Non-Ambulatory Cohort (Ages 8-19): Majority of Patients Attained Increases in HFMSE Non-Ambulatory Type

2 and Type 3 SMA Apitegromab (20 mg/kg) + nusinersenPer Protocol Population* (n=13) Apitegromab (20 mg/kg) + nusinersenIntent-to-Treat Population (n=14) Mean change from baseline in HFMSE (95% CI) +1.2 (-0.5, 2.9) +0.6 (-1.4, 2.7) # (%)

patients achieving 1-pt increase in HFMSE 9/13 (69%) 9/14 (64%) # (%) patients achieving 3-pt increase in HFMSE 4/13 (31%) 4/14 (29%) # (%) patients achieving 5-pt increase in HFMSE 2/13 (15%) 2/14 (14%) 16 Majority of patients

attained increases in HFMSE~30% achieved 3-point increase in HFMSEDurability of effect observed through 12-monthsImprovements not seen with other therapies in this older patient populationPatients already on chronic maintenance

nusinersenCHERISH data suggest older patients on average observe declines and rarely observe a 3-point increase in HFMSE *Patient had concomitant exposure to an acetylcholinesterase inhibitor, which is not permitted per the TOPAZ trial

protocol Data on file. Scholar Rock, Inc. Cambridge, MA

Safety Results from TOPAZ 12-Month Top-Line Analysis Support Evaluation of Apitegromab in Phase 3

Trial 17 Treatment-emergent adverse events (TEAEs) Apitegromab 2 mg/kg (n=10) Apitegromab 20 mg/kg (n=48) Total (n=58) Any TEAE 9 (90.0%) 44 (91.7%) 53 (91.4%) Any Serious TEAE 1 (10.0%) 4 (8.3%) 5 (8.6%) Any TEAE leading to study

drug discontinuation 0 (0.0%) 1 (2.1%) 1 (1.7%) Any Grade 3 (severe) or higher TEAE 0 (0.0%) 3 (6.2%) 3 (5.2%) Treatment-emergent adverse events (TEAEs) are defined as AEs that start after the first dose of study drug or start prior to

the administration of study drug and worsen in severity/grade or relationship to investigational medication after the administration of study drug.*TEAE rates are across all patients in TOPAZ trialData on file. Scholar Rock, Inc. Cambridge,

MA Five most frequently reported TEAEs*: Headache (24%), pyrexia (22%), upper respiratory tract infection (22%), cough (22%), and nasopharyngitis (21%). SAEs, Grade 3 AEs and AE leading to early study discontinuation were all assessed by

investigators as unrelated to study drugAnti-drug antibodies (ADA) were present at low titers following apitegromab treatment in 3 out of 58 enrolled patients. No apparent impact on drug exposure was observed and was not associated with any

hypersensitivity reactions. No safety signals identified as of the TOPAZ 12-month top-line analysis. Incidence and severity of AEs were consistent with the underlying patient population and background therapy

18 Initial Regulatory Strategy Focuses on Non-Ambulatory Patients on Background SMN Therapy Global

disease with 30,000-35,000 affected in U.S. and Europe alone Apitegromab in non-ambulatory Type 2 and 3 with background SMN upregulators 1 Ambulatory patients Smaller population but high unmet need as benefits of SMN regulators not

well-establishedTOPAZ suggests potential clinical benefit in a subset of patients 3 Type 1 patients, including those treated with gene therapy Highest incidence population and growing prevalence due to SMN upregulator treatmentTOPAZ showed

benefits of early treatment suggesting potential in Type 1 patients 2 Represents 2/3 of overall patientsMany patients already treated with or are eligible for SMN upregulator therapyImprovements in motor function on top of SMN upregulators

observed in TOPAZ Anticipated Focus of Phase 3 Trial

19 Preliminary Thoughts on Apitegromab Phase 3 Trial Design Design Subjects Key

Objectives Timeline Non-ambulatory Type 2 and Type 3 SMAPediatric population in chronic maintenance phase of SMN therapy HFMSESafety Aim to initiate by end of 2021 12-month treatment periodApitegromab IV Q4W as add-on to nusinersen or

risdiplamTOPAZ data support investigation of 20 mg/kg dose Registrational trial design subject to regulator interactions and feedback

20 Additional Opportunities May Be Pursued With Separate Regulatory Strategies Global disease with

30,000-35,000 affected in U.S. and Europe alone Apitegromab in non-ambulatory Type 2 and 3 with background SMN upregulators 1 Ambulatory patients Smaller population but high unmet need as benefits of SMN regulators not well-establishedTOPAZ

suggests potential clinical benefit in a subset of patients 3 Type 1 patients, including those treated with gene therapy Highest incidence population and growing prevalence due to SMN upregulator treatmentTOPAZ showed benefits of early

treatment suggesting potential in Type 1 patients 2 Represents 2/3 of overall patientsPatients already treated with or eligible for SMN upregulator therapyImprovements in motor function on top of SMN upregulators observed in TOPAZ

Majority of Ambulatory Patients Maintained or Improved in RHS Score from Baseline 21 Ambulatory Type 3

SMA (Intent-to-Treat Population) Apitegromab (20 mg/kg)monotherapy (n=11) Apitegromab (20 mg/kg) + nusinersen (n=12) Pooled (n=23) Mean change from baseline in RHS (95% CI) -0.4 (-3.9, 3.1) -0.3 (-2.0, 1.4) -0.3 (-2.1, 1.4) # (%)