Sarepta Therapeutics Investor Update

Sarepta Therapeutics Investor Update

SVP, Chief Medical Officer Interim Chief Executive Officer Sarepta Therapeutics Cambridge, Massachusetts, USA

Forward-Looking Statement

contains forward-looking statements. These forward-looking statements generally can be identified by the use of words such as believes or belief, anticipates, plans, expects, will,

intends, potential, possible, advance and similar expressions. These forward-looking statements include statements about the safety and efficacy of eteplirsen, analysis of eteplirsen and control cohort

data and their implications, and eteplirsen s potential as treatment for Duchenne

Muscular Dystrophy, the

potential market for our exon skipping product candidates and Sarepta s mission, commitments and business plans and strategies. Forward-looking statements also include those made during the presentation regarding future business developments

and actions and the timing of the same.

Each forward-looking statement contained in this presentation is

subject to risks and uncertainties that could cause actual results to differ materially from those expressed or implied by such statement. Applicable risks and uncertainties include, among others: the results of our ongoing research and development

efforts and clinical trials for eteplirsen and our other product candidates may not be positive or consistent with prior results or demonstrate a safe treatment benefit; there may be delays in our projected timelines or our product candidates,

chemistries or technologies may never become commercially available for regulatory or other reasons including a negative decision on our NDA for eteplirsen by an advisory committee or the FDA; agency or court decisions with respect to our patents or

those of third parties may negatively impact our business; our product candidates and or the use of or application of our chemistries and technology may fail in the research, development or commercialization process for various other reasons

including the possibility that we may not be able to comply with all regulatory requests and requirements for the research, development and commercialization of our product candidates; and those risks identified under the heading Risk

Factors in Sarepta s Annual Report on Form 10-K for the year ended December 31, 2014 filed with the Securities and Exchange Commission (SEC), Sarepta s Quarterly Report on Form 10-Q for the quarter ended June 30, 2015 and

Sarepta s other filings with the SEC, which we encourage investors to review at www.sec.gov, for a more detailed discussion on risks and uncertainties relating to our business.

Any of the foregoing risks could materially and adversely affect Sarepta s business, results of operations and the

trading price of Sarepta s common stock. We caution investors not to place considerable reliance on the forward-looking statements contained in this presentation. Sarepta does not undertake any obligation to publicly update its forward-looking

statements based on events or circumstances after the date hereof.

Professor, Neurology and Pediatrics Neuromuscular Division Washington University in St Louis St. Louis, Missouri, USA

The Ohio State University College of Medicine

Nationwide Children s Hospital

Eugenio Mercuri, MD, PhD

Professor of Pediatric Neurology Universit Cattolica del Sacro Cuore Rome, Italy

Perry Shieh, MD, PhD

Associate Professor, Department of Neurology Director, Neuromuscular Division

David Geffen School of Medicine, University of California, Los Angeles Los Angeles, California, USA

Steve Wilton, PhD, BSc

Foundation Chair in Molecular Therapy

Centre for Comparative Genomics Murdoch University Perth, Australia

All panel members either advise or consult

for Sarepta Therapeutics.

Summary of Accomplishments

activity of eteplirsen in an intention-to-treat (ITT) analysis of 6-minute walk test (6MWT) for Study 201/202 vs external control

Dystrophin production confirmed by each methodology:

Reverse-transcription polymerase chain reaction (RT-PCR)

Dystrophin intensity

% dystrophin-positive fibers

Expanded clinical program

Expanded safety database

Application (NDA) filed for accelerated approval

Key Data Included in NDA Filing

6MWT or Study 201/202 vs external control

Intermediate clinical endpoint upon which the eteplirsen NDA

Rescore of % dystrophin-positive

ITT Analysis of 6MWT for Study 201/202 vs External Control

Establishing an Appropriate External Control Cohort Per FDA Request

Only two Duchenne muscular dystrophy (DMD) registries contained longitudinal 6MWT data up to 36 months and included:

Genetic mutation data

Equivalent care standards including steroids

Prospectively defined filters were used to identify external controls from these registries

Age, steroid use, and mutation type

External control patients would have been eligible for eteplirsen 201 trial based on baseline characteristics

Leuven Neuromuscular Research

Italian DMD Telethon Center (NMRC), Belgium Eteplirsen N=97 N=89 N=12 (ITT) Clinical 6MWT 6MWT 6MWT, PFT Outcomes

6MWT, 6-minute walk test; NSAA, North Star Ambulation Assessment; PFT, pulmonary function tests.

Italian Telethon & Leuven NMRC DMD Natural History

Investigator-initiated studies,

independent of sponsor

Patients treated according to CDC/TREAT-NMD care standards

Steroid use recorded

Enrolled all patients who met eligibility criteria

Attending a participating neuromuscular clinic

Genetically confirmed diagnosis of DMD

No cognitive impairment that could affect 6MWT performance

6MWT administered by trained physical therapists according to modified American Thoracic Society procedure

Published data in peer-reviewed articles

Derivation of External Control Groups by Prospectively Defined Filters

Prospectively defined filters applied to identify

N=186 external controls (age ?7, steroids, mutation

N=116 Non-biased (recognized

institutions, databases Baseline Steroids utilized by established DMD companies)

6MWT Available Requested by FDA

N=25 N=91 All Mutations

Not Amenable to Amenable to Exon Any Exon Exon Skipping Skipping

Amenable to Amenable to Exon 51 Other Exon Skipping Exon 51 Skipping

N indicates participants at baseline; some patients did not contribute data through 36 months.

Impact of Baseline Age (<7 or ?7) on 6MWT Trends for

PATIENTS <7 SHOW IMPROVED 6MWT

PATIENTS ?7 SHOW DECLINE

Patients <7 initially improve in walking ability through 24 months and maintain 6MWT above baseline through 36 months

54-meter increase observed in the first 24 months

It is challenging to show a benefit in 6MWT in ages <7 as patients are improving due to growth & development

where growth outpaces the disease

(m) N=25 +25 m Age: 6.0 +21 m ***

Distance ** *** -31 m

Mean **p<0.01; ***p<0.001

?7 Years, Any Genotype (N=91) -143 m

Baseline Month 12 Month 24 Month 36

Difference in mean change from baseline.

Impact of Baseline Age (<7 or ?7) on 6MWT Trends in Patients Amenable to Exon Skipping

SIMILAR TREND OBSERVED IN EXON SKIP AMENABLE PATIENTS

Patients <7 initially improve in walking ability through 24 months and maintain 6MWT above baseline through 36 months

N=17 *** 400 Age: 6.0 * +50 m (m) +15

Mean *p<0.05; ***p<0.001

<7 Years, Amenable to Exon Skipping

?7 Years, Amenable to Exon Skipping (N=50)

Baseline Month 12 Month 24 Month 36

Difference in mean change from baseline.