NEW YORK – Sarepta Therapeutics on Friday said it is taking steps to expand the indication for its Duchenne muscular dystrophy gene therapy and convert its accelerated approval to traditional approval in the US.
The US Food and Drug Administration in June granted accelerated approval to Sarepta's Elevidys (delandistrogene moxeparvovec-rokl), making it the first commercially available gene therapy in the country for patients with Duchenne muscular dystrophy who are 4 or 5 years old and have a confirmed mutation in the DMD gene that causes the progressive muscle disease. Since then, it has been a priority at the company to expand the treatment's indication to DMD patients of all ages.
Elevidys is an adeno-associated virus vector-based gene therapy that delivers a copy of a gene that encodes for the protein microdystrophin. Sarepta engineered microdystrophin to carry out the normal functions of dystrophin, the protein that is lacking in patients with Duchenne muscular dystrophy.
Now, in an effort to make Elevidys indicated for all patients — something the Cambridge, Massachusetts-based company had sought to do in its original biologics license application but didn't achieve — Sarepta has submitted supplemental efficacy data from the Phase III EMBARK and Phase I ENDEAVOR trials to the FDA for priority review. The randomized, placebo-controlled EMBARK trial involved patients between 4 and 7 years old, and the open-label ENDEAVOR trial involved patients aged 2 years old and older.
Sarepta also submitted post-marketing data from the EMBARK trial hoping to provide confirmatory data on Elevidys' ability to improve patients' physical functions and mobility and convert the gene therapy's accelerated approval to traditional approval. In June, the FDA granted accelerated approval based on data from a Phase II trial showing that patients 4 to 5 years old experienced increases in microdystrophin expression 12 weeks after treatment, which the agency deemed a surrogate endpoint likely to predict clinical benefit.
As part of an agreement with Roche that Sarepta signed in 2019, Sarepta is in charge of regulatory approval and commercialization efforts for Elevidys in the US, while Roche is responsible for other regions globally.