FDA approves Marathon Pharma's Duchenne muscular dystrophy drug

The Food and Drug Administration said Thursday that it has approved privately-held Marathon Pharmaceuticals' Duchenne muscular dystrophy drug Emflaza. Emflaza is a corticosteroid that decreases inflammation and reduces the immune system's activity. Patients in a clinical trial had better muscle strength relative to patients on the placebo, the FDA said. The first drug approved in the U.S. for DMD, made by Sarepta Therapeutics Inc. , was approved last fall. Corticosteroids are used for patients with DMD in other parts of the world but have side effects such as problems with endocrine function, infection susceptibility, serious skin rashes and more, the FDA said. Sarepta shares have dropped 31.3% over the last three months, compared with a 6.7% rise in the S&P 500 .

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