Sarepta Therapeutics, Inc.
Sarepta Therapeutics, Inc., a commercial-stage biopharmaceutical company, focuses on the discovery and development of RNA-targeted therapeutics, siRNA platform, gene therapy, and other genetic therapeutic modalities for the treatment of rare diseases. It offers EXONDYS 51 for the treatment of Duchenne in patients who have a confirmed mutation of the dystrophin gene that is amenable to exon 51 skipping; VYONDYS 53 for the treatment of Duchenne in patients who have a confirmed mutation of the dystrophin gene that is amenable to exon 53 skipping; AMONDYS 45 for the treatment of Duchenne in patients who have a confirmed mutation of the dystrophin gene that is amenable to exon 45 skipping; and ELEVIDYS, an AAV-based gene therapy, which is contraindicated in patients with any deletion in exon 8 and/or exon 9 in the Duchenne gene. The company also develops SRP-9003, a gene therapy program for the treatment of LGMD2E; SRP-1001 to selectively target and knockdown DUX4 using RNAi in Phase 1/2a clinical trials; and SRP-1003 for reduction of expression of the DMPK gene in Phase 1/2a clinical trials. It has collaboration and license agreements with F. Hoffman-La Roche Ltd; Arrowhead Pharmaceuticals, Inc.; University of Western Australia; Nationwide Children's Hospital; Hansa Biopharma; and Duke University. The company was incorporated in 1980 and is headquartered in Cambridge, Massachusetts.
What does it do?
Sarepta Therapeutics makes medicines for rare genetic diseases — the kind of conditions that affect a small number of people but have almost no other treatment options. Their biggest focus is Duchenne muscular dystrophy (DMD), a devastating muscle-wasting disease that mostly affects young boys and is caused by a broken gene. Think of it like this: the gene that tells your body to make a protein called dystrophin is broken, and Sarepta makes drugs that work around or fix that break. Their newest and most important product, ELEVIDYS, is actually a gene therapy — meaning it delivers a working copy of part of that gene directly into the body.
Sarepta is one of the only companies in the world with an approved gene therapy for Duchenne, which affects roughly 1 in 3,500 boys born worldwide and has no cure. The DMD treatment market is expected to be worth billions as gene therapies move from experimental to standard of care. But the company's stock has fallen sharply in 2024-2025 after a major FDA setback, making it a high-risk, high-stakes story that the market is actively debating.
How does it make money?
Sarepta makes money by selling its approved DMD drugs directly to hospitals and specialty pharmacies. Revenue grew from $1.9 billion to $2.2 billion in the latest year, driven largely by ELEVIDYS, which launched in 2023 and commands a list price of around $3.2 million per patient — one of the most expensive drugs in the world. They also sell older exon-skipping drugs like EXONDYS 51 and VYONDYS 53, which are taken regularly and generate recurring revenue. Despite $2.2 billion in sales, the company lost $700 million, meaning the cost of running clinical trials, manufacturing gene therapies, and paying staff still exceeds what it brings in.
Why do investors care?
The core bull case is simple: if ELEVIDYS becomes standard of care for Duchenne, even treating a few hundred patients per year at $3.2 million each could generate enormous revenue. Sarepta also has a broader pipeline of RNA and gene therapies targeting other rare diseases, giving it potential beyond just DMD. However, everything hinges on ELEVIDYS maintaining its FDA approval and expanding its label — in 2024, the FDA declined to expand the drug's approval to all DMD patients regardless of age, which was a major blow. For the thesis to work, Sarepta needs to win regulatory battles, demonstrate long-term patient outcomes, and manage its cash burn.
Deep Dive
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