Sarepta Therapeutics Inc saw its shares advance after Chugai Pharmaceutical Co., Ltd. moved ELEVIDYS into commercial distribution in Japan following the therapy's inclusion on Japan’s National Health Insurance price list. The commercial start in Japan triggered a $40 million milestone payment to Sarepta, payable upon the first commercial sale in that market under the companies' collaboration agreement with Roche.
ELEVIDYS represents the first gene therapy launched in Japan specifically to treat Duchenne muscular dystrophy. The therapy's approved indication in Japan covers ambulatory patients aged 3 to less than 8 years who have a deletion affecting any portion or the entirety of exon 8 and/or exon 9 of the DMD gene, and who test negative for anti-AAVrh74 antibodies.
The launch follows conditional and time-limited approval granted by Japan's Ministry of Health, Labour and Welfare in May 2025. As part of the Roche Group collaboration, Chugai will carry out postmarketing clinical studies and surveillance in Japan to monitor long-term efficacy and safety.
Regulatory authorization in Japan was supported by efficacy and safety findings from ELEVIDYS' clinical development program, notably results from the global Phase 3 EMBARK study. EMBARK assessed ELEVIDYS in ambulatory boys with Duchenne muscular dystrophy and reported clinically meaningful improvements in key motor function endpoints.
Across clinical trials and real-world use, ELEVIDYS has been administered to more than 1,200 patients globally. Two-year EMBARK results were published in Neurology & Therapy in January, and three-year results are scheduled for presentation at an upcoming medical congress.
Under the terms of Sarepta's 2019 collaboration agreement with Roche, Sarepta retains responsibility for regulatory approvals and commercialization of ELEVIDYS in the United States, as well as for manufacturing. Roche is tasked with seeking regulatory approvals and commercializing the therapy outside the U.S., with Chugai acting as Roche's commercialization partner in Japan.
Market and commercial context
The initial commercial sale in Japan not only establishes ELEVIDYS as the first gene therapy available there for Duchenne muscular dystrophy but also creates an immediate contractual payment to Sarepta tied to that sale. Chugai's postmarketing obligations will form part of the longer-term evidence generation strategy supporting the therapy's safety and efficacy profile in the Japanese population.
Clinical evidence cited for approval
- Approval drew on the global ELEVIDYS clinical development program, with Phase 3 EMBARK results cited for demonstrated motor function benefits.
- Publication of two-year EMBARK data in a peer-reviewed journal and upcoming three-year data presentation contribute to the post-approval evidence landscape.
Commercial responsibilities
- Sarepta: U.S. regulatory approvals, U.S. commercialization, and manufacturing.
- Roche/Chugai: Regulatory approvals and commercialization outside the U.S., with Chugai handling Japan.