The U.S. Food and Drug Administration revised the label for Sarepta’s Duchenne muscular dystrophy gene therapy Elevidys, adding a boxed safety warning and restricting use to ambulatory patients while requesting a postmarketing study. The agency’s action directly addresses physician concerns about therapy‑related risks and will reshape Elevidys’ clinical positioning and prescribing practices. Regulators added explicit safety language and limited the indicated population after reviewing emerging real‑world and trial safety data. Sarepta must now design and run a postmarketing study to clarify long‑term safety in treated patients, and clinicians will face tighter eligibility criteria for gene‑therapy referral. The FDA move underscores ongoing scrutiny of in‑vivo gene therapies and the agency’s emphasis on postlaunch evidence generation. Companies developing gene therapies should expect more conservative initial labels and enforcement of rigorous postmarketing commitments, particularly where safety signals appear in early commercialization.