FDA Weighs Quick OK for Muscular Dystrophy Gene Therapy

2 min read

May 3, 2023 -- A drug maker is seeking FDA approval to treat a rare form of muscular dystrophy with what would be the first gene therapy OK’d through the agency’s accelerated approval process.

“The request has reportedly triggered intense debate within the FDA,” NPR reports.

The request comes from Sarepta Therapeutics, which says its experimental gene therapy infuses trillions of harmless viruses that have been genetically modified to deliver a gene to the muscles. 

“The gene produces a miniature version of a protein called dystrophin, that boys with muscular dystrophy are missing or don't have enough of. The hope is this ‘micro-dystrophin’ will at least help slow the progression of the disease,” NPR says.

Sarepta bases its belief on how much micro-dystrophin the gene therapy produces in the muscles. It doesn’t have direct evidence that the treatment alleviates symptoms or prevents the disease from getting worse.

The FDA says independent advisers will consider the request for accelerated approval on May 12. That would grant FDA approval before strong evidence shows the treatment works as long as companies promise to prove later that it works.

The disease mostly strikes boys and destroys muscles. People usually die from it in their 30s and 40s.

"We're dealing with a very serious rare disease. A deadly disease. Every day matters to these patients," Sarepta CEO Douglas Ingram told NPR. "This could be the most important therapy so far developed for children with Duchenne muscular dystrophy. We have, at least from our perspective, the perfect opportunity to use the accelerated approval pathway."

Reshma Ramachandran, MD, who studies drug approvals at Yale, says Sarepta hasn’t followed up on three previous treatments that were granted accelerated approval.

"We're still left uncertain whether or not these very expensive treatments actually yield a meaningful clinical benefit, or if we're just simply still guessing," Ramachandran said.

She says families of Duchene muscular dystrophy patients would be better of focusing on physical therapy and in-home care, rather than the expensive treatment. Sarepta has not disclosed the cost, but similar therapies have reached $3 million per patient.