Biotech stock explodes 80% after the FDA approves the first drug to treat a rare muscle disorder

Sarepta Therapeutics shares spiked by as much as 86% in trading on Monday after the US Food and Drug Administration said it approved a key drug.

The FDA approved Exondys 51 (eteplirsen), the first such drug to treat patients with Duchenne muscular dystrophy (DMD), it said in a statement.

DMD is a rare disorder caused by the absence of dystrophin, a protein that helps keep muscle cells intact, and causes gradual but severe damage while limiting movement. Patients could need wheelchairs even in their early teens, and could die by the time they are in their 30s.

The FDA confirmed last week that Dr. Ronald Farkas, a key staffer who opposed the drug had left the agency, Stat News reported. Sarepta shares soared then, as Farkas' departure was seen by investors to pave the way for approval.

The agency had been under growing pressure to endorse the drug, following the rejection of two treatments from other companies, Stat News noted.

"Accelerated approval makes this drug available to patients based on initial data, but we eagerly await learning more about the efficacy of this drug through a confirmatory clinical trial that the company must conduct after approval," said Janet Woodcock, director of the FDA's Center for Drug Evaluation and Research, in the statement.

Sarepta shares were halted for volatility after the spike on Monday.

Investing.com

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