Deep InsightsAdvancingImpactful Medicines January 2023 Disclaimers Various statements in this presentation concerning the future expectations, plans and prospects of Scholar Rock, Inc. ("Scholar Rock"), including without

Deep InsightsAdvancingImpactful Medicines January 2023

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 apitegromab, SRK-181, and other product candidates and indication selection and development timing, its cash runway, the ability of any product candidate to perform in humans in a manner consistent with

earlier nonclinical, preclinical or clinical trial data, and the potential of its product candidates and proprietary platform. The use of words such as "may," "could," "might," "will," "should," "expect," "plan," "anticipate," "believe,"

"estimate," "project," "intend," "future," "potential," or "continue," and other similar expressions are intended to identify such forward-looking statements for the purposes of the safe harbor provisions under The Private Securities

Litigation Reform Act of 1995. All such forward-looking statements are based on management's current expectations of future events and are subject to a number of risks and uncertainties that could cause actual results to differ materially and

adversely from those set forth in or implied by such forward-looking statements. These risks and uncertainties include, without limitation, that preclinical and clinical data, including the results from the Phase 2 trial of apitegromab or

Part A of the Phase 1 trial of SRK-181, are not predictive of, may be inconsistent with, or more favorable than, data generated from future clinical trials of the same product candidate, including the Phase 3 clinical trial of apitegromab in

SMA and Part B of the Phase 1 clinical trial of SRK-181, respectively, Scholar Rock's ability to provide the financial support, resources and expertise necessary to identify and develop product candidates on the expected timeline, the data

generated from Scholar Rock's nonclinical and preclinical studies and clinical trials, information provided or decisions made by regulatory authorities, competition from third parties that are developing products for similar uses, Scholar

Rock's ability to obtain, maintain and protect its intellectual property, the success of Scholar Rock's current and potential future collaborations, Scholar Rock's dependence on third parties for development and manufacture of product

candidates including, without limitation, to supply any clinical trials, 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, and the impacts of current macroeconomic and geopolitical events, including changing conditions from the COVID-19 pandemic, hostilities in Ukraine, increasing rates of inflation and rising interest

rates, on business operations and expectations, as well as those risks more fully discussed in the section entitled "Risk Factors" in Scholar Rock's Quarterly Report on Form 10-Q for the quarter ended September 30, 2022, 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. All information in this press release is as of the date of the release, and Scholar Rock undertakes no duty to update this information unless required by

law. Apitegromab and SRK-181 are investigational drug candidates under evaluation. Apitegromab and SRK-181 have not been approved for any use by the FDA or any other regulatory agency and the safety and efficacy of apitegromab and SRK-181

Scholar Rock: Transforming Patient Lives, Targeting High Unmet Medical Need 3 Global leader in TGFB

superfamily biology Targeting the latent forms of growth factors Exquisite selectivity to deliver differentiated therapeutic profiles Revolutionary Platform Rich preclinical pipeline focused on high unmet patient needs Phase 3

SAPPHIRE study underway, data readoutexpected in 2024 Phase 1 POC DRAGON study underway in immuno-oncology Neuromuscular and Beyond Compelling proof-of-concept TOPAZ data informed Phase 3 SAPPHIRE study design Seasoned leadership team

with track record of clinical and commercial success Anticipated cash runway into 2025 Positioned for Success Commercial planning underway for apitegromab (SMA) in US and Europe Broad platform, including promising early-stage assets,

provides opportunities to advance alone or in partnership Strategic Optionality

Revolutionary Approach to Regulating TGF Superfamily Implicated in Devastating Diseases 4 Scholar

Rock's R&D Platform Transforming Medical Practice Selectively target the latent form of growth factors in the microenvironment of cells and tissues with uniquely designed antibodies Overcome the challenges that plague traditional

approaches that target the "mature" growth factor, which are difficult to differentiate and lead to unintended negative effects Scholar Rock's TargetLatent Growth Factor Traditional Target"mature" growth factor TGF Superfamily: Highly

Sought-After Targets Dysregulation plays a role in devastating diseases that have a high unmet need including: Neuromuscular disorders Fibrosis Oncology Recognized by the industry as important targets given their fundamental roles in

regulating a variety of cellular processes

DISCOVERY/PRECLINICAL PHASE 1 PHASE 2 PHASE 3 2023 MILESTONES SPINAL MUSCULAR ATROPHYApitegromab

(selective anti-latent myostatin) 36-month TOPAZ data SAPPHIRE: LPI IMMUNO-ONCOLOGYSRK-181 (Selective context-independent, anti-latent TGF -1) Rolling clinical data updates ANEMIASelective anti-RGMc IND-enabling

studies FIBROSIS Selective context-dependent (LTBP1 & LTBP3) anti-latent TGF -1 IND-enabling studies Robust Pipeline of Novel Product Candidates 5 Potential to transform the lives of patients suffering from a wide range of serious

diseases, including neuromuscular disorders, oncology, and fibrosis

Leadership Team: Experienced in Drug Development and Commercialization 6 Jay Backstrom, MD,

MPH President & CEO 30 years of clinical R&D experience, leading multiple successful regulatory approvals Ted Myles, MBA Chief Operating Officer & CFO 25 years of progressive experience in clinical and commercial-stage

companies 25 years of experience leading HR, culture transformation, leadership development, DEI, and talent management Caryn Parlavecchio Chief Human Resources Officer 15 years of experience leading and advising life sciences companies

in areas of legal and compliance Junlin Ho, JD General Counsel &Corporate Secretary Mo Qatanani, PhD SVP, Research 15 years of industry experience on the strategic and operational sides of research & development Jing Marantz,

MD, PhD, MBA Chief Medical Officer 20 years of industry expertise across clinical pharmacology, neurology, hematology/oncology, and rare diseases

Apitegromab: The Next Potential Transformative Therapy for Patients with Spinal Muscular Atrophy (SMA)

Apitegromab: Potential Muscle-Directed Therapy for SMA 8 * Based on Animal Model Data; 1. Adapted

from: SMA Foundation Overview. http://www.smafoundation.org/wp-content/uploads/2012/03/SMA-Overview.pdf.; Accessed April 18, 2021; 2. Long KK, et al. Hum Mol Genet. 2019;28(7):1077-1088; 3. Pirruccello-Straub M, et al. Sci Reports.

2018;8(1):2292. doi:10.1038/s41598-018-20524-9 Apitegromab is a MUSCLE-DIRECTED APPROACH aimed at improving motor function*2,3 Myostatin is a negative regulator of skeletal muscle growth Apitegromab is a fully human, mAb that

specifically binds to proforms of myostatin and inhibits myostatin activation leading to increased muscle mass and muscle function Strong evidence indicates upstream targeting of structurally differentiated latent myostatin avoids

undesirable off-target effects Apitegromab Muscle fiber atrophy SMN-directed therapiesPREVENT FURTHER DEGENERATION of motor neurons1 ...but do not directly address muscle atrophy Motor neuron degeneration

9 *TOPAZ Phase 2 trial evaluated patients with Type 2 and 3 SMA (did not include Type 1) 1. Lally et

al, Orphanet Journal of Rare Diseases, 2017; 2. SMA Europe. SMATracker. About SMA. Accessed January 24, 2022. https://smatracker.eu/what-is-spinal-muscular-atrophy; 3. National Organization for Rare Disorders. Spinal muscular atrophy.

Accessed January 24, 2022. https://rarediseases.org/rare-diseases/spinal-muscular-atrophy/. 4. Cure SMA. Care Series Booklet. Accessed September 19, 2021. 2020.

https://www.curesma.org/wpcontent/uploads/2020/08/08262020_Understanding_SMA_vWeb.pdf. Apitegromab is an investigational drug candidate being evaluated for the treatment of spinal muscular atrophy. Apitegromab has not been approved for any

use by the US FDA or any other health authority, and its safety and efficacy have not been established. Severe, progressive disabilities and unable to walk independently Significant, progressive motor function impairment; many lose

ambulation Infantile onset; unable to sit up independently Type 3 35% Type 2 51% Type 1 14% TOPAZ* 12-month results showed transformative potential in non-ambulatory Types 2 and 3 patients >2/3 of overall patient population KBV

Research and secondary Research Analysis. Global Spinal Muscular Atrophy Market Analysis (2022-2028). November 2022, p. 42 Global SMA Treatment Market expected to reach $11.4B by 2028 Spinal Muscular Atrophy Motor neuron impairment and

loss due to SMN genetic deficiency, leading to muscle atrophy and weakness GLOBAL DISEASE: 30,000-35,000 affected in US and Europe alone1, 2, 3,4

Patients continue to experience major functional impairments despite utilization of SMN-directed

therapies Potential to Pioneer a New Treatment Era: Opportunity for Muscle-Directed Therapy to Complement SMN-Directed Therapies 10 PHASE 3 TRIAL DESIGN Type 1, 2 ,3 1 day -12 years of age (Non-ambulatory recruited) Type 1, 2, 3 1

month - 25 years of age (Ambulatory and Non-ambulatory recruited) Type 1 up to 6 months of age (Non-ambulatory recruited) PRIMARY ENDPOINT Mean change from baseline in HFMSE at 15 months Mean change from baseline in MFM-32 at 12

months Ability to sit independently and event-free survival INITIAL INDICATION Spinal Muscular Atrophy (SMA) in pediatric and adult patients Spinal Muscular Atrophy (SMA) in pediatric and adult patients Spinal Muscular Atrophy (SMA) in

pediatric patients less than 2 years CURRENT MARKET PENETRATION Patients treated WW: >11,000* Revenues (LTM): $1.7+ billion Patients treated WW: >7000** Revenues (YTD'0922): ~CHF 793 million Patients treated WW: >2500***

Revenues (LTM): $ 1.4+ billion *As of Biogen SPINRAZA website and 3Q22 financial update on 10/25/22; includes patients treated worldwide in post-marketing setting, expanded access program, and clinical trials. **As of Roche YTD Sep'2022

financial update on 10/18/22; includes patients treated worldwide between clinical trials, commercial, and compassionate use program. ***As of Novartis 3Q22 financial update on 10/25/22; commercially, via managed access programs and in

clinical trials HFMSE = Hammersmith Functional Motor Scale Expanded; MFM-32 = Motor Function Measure - 32 items Refer to most current USPI

Apitegromab Offers Potential to Address Unmet Patient Need 11 HFMSE=Hammersmith Functional Motor

Scale-Expanded 1. Mercuri E et al.; N Engl J Med 2018; 378:625-635; DOI: 10.1056/NEJMoa1710504; cherish trial results. 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 experienced by patients with non-ambulatory Types 2/3 SMA in nusinersen Phase 3 CHERISH trial 3.9-point increase in HFMSE from nusinersen(4.9 point increase relative to sham

control) HFMSE Score at Month 15 Total Possible HFMSE Score of 66 Unmet need remains substantial

Phase 2 TOPAZ Trial: Safety and Efficacy Data from First Muscle-directed Treatment Candidate in SMA

TOPAZ Age 2-12 Analysis* in Pooled Non-Ambulatory Cohorts (20mg/kg) Transformative Potential as Add-On

for Apitegromab1,2 13 Mean HFMSE Increase OF 4.4 POINTS with majority experiencing 3-point increases on top of background SMN therapy HFMSE Gains Also Notable in subset of individuals in this analysis who had started background

nusinersen at age 5: 75% (6/8) with 1-point increase 50% (4/8) with 3-point increase Non-Ambulatory Types 2/3 SMA (Apitegromab 20 mg/kg; Intent-to-Treat Population) Age 2-12 years (n=16 ) Mean HFMSE change from baseline, (95%

CI) +4.4 (1.3, 7.4) Patients with 1-pt increase in HFMSE, n (%) 13 (81%) Patients with 3-pt increase in HFMSE, n (%) 9 (56%) TOPAZ results showed HFMSE improvement from baseline or RHS stabilization across all three pre-specified

cohorts.1 *Exploratory, post hoc analysis; For 12-month endpoint, if patients skipped three consecutive doses due to site restrictions caused by COVID-19, records after dose skipping were excluded from analysis. The last observation carry

forward was used for other missing data; 1.Crawford T et al. TOPAZ topline results; Presented at CureSMA, 2021 Virtual SMA Research & Clinical Care Meeting; June 9-11, 2021. 2. Scholar Rock Inc. Corporate Presentations, August 2022 at

Deep Insights, Impactful Medicines (scholarrock.com) Apitegromab is an investigational drug candidate being evaluated for the treatment of spinal muscular atrophy. Apitegromab has not been approved for any use by the US FDA or any other

health authority, and its safety and efficacy have not been established. No safety signals for apitegromab were identified to date; the five most frequently reported treatment-emergent adverse events were headache, pyrexia, upper respiratory

tract infection, cough, and nasopharyngitis

Sizable, Sustained Increases in HFMSE Observed Over 24 Months of ApitegromabPooled Non-Ambulatory

Patients Excluding Data Post Scoliosis Surgery (all dose groups) 14 For the 24-month evaluation, an observed case analysis was conducted, which pooled all the non-ambulatory patients (Cohorts 2 and 3) and was based upon the available data

for given timepoints. This analysis population included patients receiving either low dose (2 mg/kg) or high dose (20 mg/kg) apitegromab (inclusive of patients in Cohort 3 who switched from 2 mg/kg to 20 mg/kg in Year 2). This analysis

excludes from the observed case analysis any HFMSE data following scoliosis surgery in TOPAZ. Of the three non-ambulatory patients who had scoliosis surgery, data from one was excluded and the other two did not have valid HFMSE assessments.

Error bars represent SEM. Values in parentheticals represent 95% confidence interval. Crawford T et al. TOPAZ EXTENSION: 24-MONTH EFFICACY AND SAFETY OF APITEGROMAB IN PATIENTS WITH LATER-ONSET SPINAL MUSCULAR ATROPHY (TYPE 2 AND TYPE 3 SMA)

Podium Presentation Presented at CureSMA; June 2022. Data on File. Scholar Rock, Inc. Cambridge, MA. Apitegromab is an investigational drug candidate being evaluated for the treatment of spinal muscular atrophy. Apitegromab has not been

approved for any use by the US FDA or any other health authority, and its safety and efficacy have not been established. Age 2-21 Years Age 2-12 Years n= 35 29 32 28 n= 29 23 26 23 Mean Change from Baseline in HFMSE (95% CI)

Continued Increase in RULM Observed at 24 Months of Apitegromab Pooled Non-Ambulatory Patients

Excluding Data Post Scoliosis Surgery (all dose groups) 15 For the 24-month evaluation, an observed case analysis was conducted, which pooled all the non-ambulatory patients (Cohorts 2 and 3) and was based upon the available data for given

timepoints. This analysis population included patients receiving either low dose (2 mg/kg) or high dose (20 mg/kg) apitegromab (inclusive of patients in Cohort 3 who switched from 2 mg/kg to 20 mg/kg in Year 2). This analysis excludes data

from 3 non-ambulatory patients after their scoliosis surgery during TOPAZ from the Observed Case Analysis. Error bars represent SEM. Values in parentheticals represent 95% confidence interval. Crawford T et al. TOPAZ EXTENSION: 24-MONTH

EFFICACY AND SAFETY OF APITEGROMAB IN PATIENTS WITH LATER-ONSET SPINAL MUSCULAR ATROPHY (TYPE 2 AND TYPE 3 SMA) Podium Presentation Presented at CureSMA; June 2022. Data on File. Scholar Rock, Inc. Cambridge, MA. Apitegromab is an

investigational drug candidate being evaluated for the treatment of spinal muscular atrophy. Apitegromab has not been approved for any use by the US FDA or any other health authority, and its safety and efficacy have not been

established. n= 34 28 31 30 n= 28 22 25 25 Mean Change from Baseline in RULM (95% CI) Age 2-21 Years Age 2-12 Years

No Serious Safety Risks IdentifiedOver 24 Months of Apitegromab Treatment 16 Treatment-Emergent

Adverse Events (TEAEs)* 2 mg/kg dose (N=10) n (%) 20 mg/kg dose (N=48) n (%) Total (N=58) n (%) Any TEAE 10 (100) 45 (93.8) 55 (94.8) Any Serious TEAE 3 (30) 11 (22.9) 14 (24.1) Any TEAE leading to study drug

discontinuation 0 (0.0) 1 (2.1) 1 (1.7) Any Grade 3 (severe) or higher TEAE 2 (20) 9 (18.8) 11 (19) Crawford T et al. TOPAZ EXTENSION: 24-MONTH EFFICACY AND SAFETY OF APITEGROMAB IN PATIENTS WITH LATER-ONSET SPINAL MUSCULAR ATROPHY

(TYPE 2 AND TYPE 3 SMA) Podium Presentation Presented at CureSMA; June 2022 *Notes: % = 100 x n/N (n=incidence) **51/57 patients Treatment-emergent adverse events (TEAEs) are defined as adverse events (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. Data is for safety events collected over the 24-month period

and includes patients who switched from 2 mg/kg to 20 mg/kg. Data on file, extracted on April 7, 2022. Scholar Rock, Inc. Cambridge, MA. Apitegromab is an investigational drug candidate being evaluated for the treatment of spinal muscular

atrophy. Apitegromab has not been approved for any use by the US FDA or any other health authority, and its safety and efficacy have not been established. Incidence and types of TEAEs were consistent with the underlying disease or nusinersen

therapy Five most frequently reported TEAEs were headache, pyrexia, upper respiratory tract infection, cough, and nasopharyngitis No deaths or Suspected Unexpected Serious Adverse Reactions (SUSARs) reported Adverse events reported as

mostly mild to moderate in severity No identified serious risks as of 4/7/2022 approximately 90% remain on apitegromab as of 12/31/2022**

Sapphire Phase 3 Pivotal Trial

Ongoing SAPPHIRE Phase 3 Trial Overview 18 Randomized, double-blind, placebo-controlled, parallel arm

design (n=204) Enrolling patients on SMN-directed therapy (nusinersen or risdiplam) Anticipate completing enrollment in 2023 TREATMENT (52 weeks) Apitegromab (20 mg/kg IV q4w) + SMN-directed therapy Apitegromab (10 mg/kg IV q4w) +

SMN-directed therapy Placebo (IV q4w) + SMN-directed therapy SCREENING MAIN POPULATION (n=156) Ages 2-12 With non-ambulatory Types 2 and 3 SMA N=52 N=52 N=52 R Stratified randomization to ensure balanced allocation: Age at SMN