"The groundwork of all happiness is health." - Leigh Hunt

FDA considers rapid approval of gene therapy for muscular dystrophy

May 3, 2023 – A drugmaker is applying to the FDA for approval to treat a rare type of muscular dystrophy using a technique that will be the primary to undergo the agency’s expedited approval process.

“The request reportedly sparked a heated debate within the FDA,” NPR reports.

The request comes from Sarepta Therapeutics. The company says its experimental gene therapy involves injecting trillions of harmless viruses which were genetically modified to move a gene into the muscles.

“The gene produces a miniature version of a protein called dystrophin, which boys with muscular dystrophy lack or do not have enough of. The hope is that this 'micro-dystrophin' will at least help slow the progression of the disease,” NPR says.

Sarepta bases its hypothesis on how much microdystrophin the gene therapy produces within the muscles. There is not any direct evidence that the treatment relieves symptoms or prevents the disease from getting worse.

The FDA says independent advisers will review the appliance for accelerated approval on May 12. This would allow the FDA to grant approval before there is evident evidence of the treatment's effectiveness, provided the businesses promise to reveal effectiveness later.

The disease mainly affects boys and results in muscle destruction. Those affected normally die between the ages of 30 and 40.

“We are dealing with a very serious rare disease. A fatal disease. For these patients, every day counts,” Sarepta CEO Douglas Ingram told NPR. “This could be the most important therapy yet for children with Duchenne muscular dystrophy. We have, at least from our point of view, the perfect opportunity to use the accelerated approval procedure.”

Reshma Ramachandran, MD, who researches drug approvals at Yale, says Sarepta didn't follow up on three previous treatments that had been granted accelerated approval.

“We are still uncertain whether these very expensive treatments actually provide meaningful clinical benefit or whether this is just speculation,” Ramachandran said.

She says families of patients with Duchene muscular dystrophy could be higher off specializing in physical therapy and residential care reasonably than undergoing the expensive treatment. Sarepta has not disclosed costs, but similar therapies already cost $3 million per patient.