Sarepta Therapeutics : J.P. Morgan 2022 Presentation

Some see slow and steady scientific progress.

We see a revolution.

DOUG INGRAM

President and CEO

J.P. Morgan 40th Annual Healthcare Conference

January 10, 2022

SETH

Living with Duchenne muscular dystrophy

Forward-looking Statements

This presentation contains "forward-looking statements." Any statements that are not statements of historical fact may be deemed to be forward-looking statements. Words such as "believe," "anticipate," "plan," "expect," "will," "may," "intend," "prepare," "look," "potential," "possible" and similar expressions are intended to identify forward-looking statements. These forward-looking statements include statements relating to our future operations, financial performance and projections, business plans, market opportunities, priorities and research and development programs; the estimated number of patients suffering from Duchenne; the potential for our precision genetic medicine engine to generate a steady stream of personalized medicine therapeutics; the potential benefits of our technologies and scientific approaches; the potential benefits of SRP-9001, including the potential benefits of our SRP-9001 gene therapy construct; our belief that Study SRP-9001-102 results increase confidence in design and probability of success of Study 301 (EMBARK); the potential to seek accelerated approval for SRP-5051; our expected product revenue guidance of >$800M in 2022; and expected milestones and plans, including completing enrollment for EMBARK by mid-2022, announcing additional SRP-9001 data at a medical conference, discussing with the FDA the fastest potential path to bringing SRP-9001 to our community of patients and their families, submitting a BLA for SRP-9001 after a read out of EMBARK next year that is consistent with the totality of evidence of the benefits of SRP-9001, announcing SRP-9003-

101 3-year data for low dose cohort and 2-year data for high dose cohort, finalizing our strategy for sarcoglycans (SRP-9003,SRP-9005,SRP-9004), starting our POC trial for SRP-6004 (Dysferlin) in late 2022, advancing earlier stage pipeline candidates through our partnered and internal programs, fully enrolling MOMENTUM Part B SRP-5051 by 2H22, advancing PPMO candidates for exons 45, 52 and 53, continuing the growth of our PMO-focused RNA franchise and advancing our gene editing programs and expanding our capabilities at our Gene Editing Innovation Center.

These forward‐looking statements involve risks and uncertainties, many of which are beyond our control and are based on our current beliefs, expectations and assumptions regarding our business. Actual results and financial condition could materially differ from those stated or implied by these forward‐looking statements as a result of such risks and uncertainties, and such risks and uncertainties could materially and adversely affect our business, results of operations and trading price. Potential known risk factors include, among others, the following: our data for our different programs, including PPMO and gene therapy-based product candidates, may not be sufficient for obtaining regulatory approval; our product candidates, including those with strategic partners, may not result in viable treatments suitable for commercialization due to a variety of reasons, including the results of future research may not be consistent with past positive results or may fail to meet regulatory approval requirements for the safety and efficacy of product candidates; success in preclinical testing and early clinical trials, especially if based on a small patient sample, does not ensure that later clinical trials will be successful; the expected benefits and opportunities related to our agreements with our strategic partners may not be realized or may take longer to realize than expected due to a variety of reasons, including any inability of the parties to perform their commitments and obligations under the agreements, challenges and uncertainties inherent in product research and development and manufacturing limitations; if the actual number of patients living with Duchenne or LGMD is smaller than estimated, our revenue and ability to achieve profitability may be adversely affected; we may not be able to comply with all FDA post-approval commitments and requirements with respect to EXONDYS 51, VYONDY 53 and AMONDYS 45 in a timely manner or at all; our dependence on our manufacturers to fulfill our needs for our clinical trials and commercial supply, including any failure on our part to accurately anticipate product demand and timely secure manufacturing capacity to meet product demand, may impair the availability of products to successfully support various programs, including research and development and the potential commercialization of our gene therapy product candidates; we may not be able to successfully scale up manufacturing of our product candidates in sufficient quality and quantity or within sufficient timelines; current reimbursement models may not accommodate the unique factors of our gene therapy product candidates; we may not be able to execute on our business plans and goals, including meeting our expected or planned regulatory milestones and timelines, clinical development plans, and bringing our product candidates to market, for various reasons including possible limitations of our financial and other resources, manufacturing limitations that may not be anticipated or resolved for in a timely manner, regulatory, court or agency decisions, such as decisions by the United States Patent and Trademark Office, the ongoing COVID-19 pandemic; and those risks identified under the heading "Risk Factors" in Sarepta's most recent Annual Report on Form 10-K and most recent Quarterly Report on Form 10‐Q filed with the Securities and Exchange Commission (SEC) and in its other SEC filings.

For a detailed description of risks and uncertainties Sarepta faces, you are encouraged to review Sarepta's filings with the SEC. We caution investors not to place considerable reliance on the forward‐looking statements contained in this presentation. The forward‐looking statements in this presentation are made as of the date of this presentation only and, other than as required under applicable law, Sarepta does not undertake any obligation to publicly update its forward‐looking statements.

©SAREPTA THERAPEUTICS, INC. 2022. ALL RIGHTS RESERVED.	2

Duchenne Muscular Dystrophy (DMD)

DMD affects approximately

1 in 3,500-5,000 males worldwide1

• DMD is a rare, fatal neuromuscular genetic disease inherited in an X-linked recessive pattern2
• Muscle weakness becomes increasingly noticeable by 3 to 5 years of age, and most patients use a wheelchair by the time they are 11 years old2
• During adolescence, cardiac and respiratory muscle deterioration lead to serious, life-threatening complications3

1. National Institutes of Health. Genetics Home Reference. Duchenne and Becker muscular dystrophy.
https://ghr.nlm.nih.gov/condition/duchenne-and-becker-muscular-dystrophy. Accessed Jan 2020.
2. Hoffman EP, Brown RH, et al. Dystrophin: the protein product of the Duchenne muscular dystrophy locus. Cell. 1987;51:919-928.
3. Passamano L, Taglia A, et al. Improvement of survival in Duchenne Muscular Dystrophy: retrospective analysis of 835 patients. Acta Myologica. 2012;31(1): 121-125.	©SAREPTA THERAPEUTICS, INC. 2022. ALL RIGHTS RESERVED.	3

SRP-9001 Gene Therapy Construct

VECTOR

AAVrh74

• Provides systemic delivery to

muscle cells, including the heart and skeletal muscle

• Low level of pre- existing immunity

PROMOTER

MHCK7

TRANSGENE

MICRO-DYSTROPHIN

• Designed to generate a functional micro-dystrophin
• Includes SR2 and SR3 - essential for muscle force3

• Optimized for desired skeletal and cardiac muscle expression levels
• 120% expression in cardiac muscle vs skeletal muscle1,2

1. Potter et al. Functional and Histological Improvements Comparing 4 Micro-dystrophin Constructs in the mdx Mouse Model of DMD. ASGCT 2019.
2. Potter et al. Functional and Histological Improvements Comparing 4 Micro-dystrophin Constructs in the mdx Mouse Model of DMD. AIM 2019.
3. Nelson DM, Ervasti JM, et al. Variable rescue of microtubule and physiological phenotypes in mdx muscle expressing different miniaturized

dystrophins. Human Molecular Genetics, 2018, Vol. 27, No. 12: 2090-2100.

©SAREPTA THERAPEUTICS, INC. 2022. ALL RIGHTS RESERVED.

4

SRP-9001-102: Study Design

Randomized, double-blind,placebo-controlled study

An ongoing Phase 2 study is evaluating the safety, efficacy and tolerability of a single IV dose of SRP-9001 (1.33x1014 vg/kg), compared to placebo, in boys with DMD aged 4-7 years old

Double-blindplacebo-controlled

			Single IV infusion		Single IV infusion
			SRP-9001
				placebo
			(n=20)
Randomization							Open-label
(n=41)							extension period
		Single IV infusion placebo	Single IV infusion
			(n=21)		SRP-9001

Part 3

Part 1:	Part 2:
48 weeks	48 weeks

©SAREPTA THERAPEUTICS, INC. 2022. ALL RIGHTS RESERVED.	5