Sarepta’s Duchenne gene therapy fails to meet primary endpoint in pivotal trial

Sarepta Therapeutics said Monday afternoon that its gene therapy for Duchenne muscular dystrophy failed to improve muscle function compared to a placebo in a large clinical trial — likely a major disappointment for patients and doctors who have been desperately awaiting the treatment for years.

The company said all patients in the study improved and that secondary measurements indicated the drug was having an effect. Nevertheless, the results are likely to raise questions about whether the Food and Drug Administration will expand access to the medicine.