FDA Restricts Use of Sarepta's Gene Therapy, Adds Safety Warnings

Core Insights - The FDA has approved significant changes to the label of Sarepta Therapeutics' Elevidys, a gene therapy for Duchenne muscular dystrophy (DMD), narrowing the eligible patient population and adding new safety restrictions [1][2][4]. Summary by Sections Label Changes - Elevidys is now approved only for ambulatory patients aged four years and older with DMD, excluding non-ambulatory patients [2][4]. - A boxed warning has been mandated, highlighting risks of acute liver failure (ALF) and acute liver injury (ALI) [2][4]. - Additional limitations include restrictions for patients with pre-existing liver impairment, recent vaccinations, or active/recent infections [3][8]. Monitoring and Studies - New monitoring requirements include weekly liver function tests for at least three months post-treatment [3][8]. - Patients must remain near a medical facility for at least two months after infusion to ensure rapid access to care if complications arise [3][8]. - Sarepta is required to conduct an observational study enrolling approximately 200 DMD patients to evaluate the risk of serious liver injury over at least 12 months [5][8]. Market Reaction - Despite the substantial label changes, Sarepta's stock rose nearly 6% following the announcement, indicating investor relief that Elevidys was not completely withdrawn from the market [6][8]. - Year-to-date, the stock has plummeted nearly 85%, contrasting with the industry's 15% growth [7]. Future Developments - To address safety issues, Sarepta is developing a revised treatment protocol with an enhanced sirolimus-based immunosuppressive regimen aimed at reducing acute liver complications [10]. - A clinical study of this updated regimen is planned to potentially resume dosing in the non-ambulatory population pending FDA review [10][11].