Sarepta climbs on new data for muscle drug

NEW YORK (AP) -- Shares Sarepta Therapeutics jumped Thursday after the company said its muscle disorder drug eteplirsen continued to help patients after more than two years of treatment.

THE SPARK: Sarepta reported results from an extended study of the drug on Wednesday after the market closed. It said boys who were treated with eteplirsen continued to show stabilization of walking ability after 120 weeks of treatment.

The results come from a mid-stage clinical trial involving 12 boys between the ages of 7 and 13. They have Duchenne muscular dystrophy, a rare and fatal genetic disease that causes increasing muscle weakness. It affects one of every 3,500 boys born worldwide.

THE BIG PICTURE: Sarepta Therapeutics Inc. is based in Cambridge, Mass., and it does not have any drugs approved for sale. It is studying treatments for Duchenne muscular dystrophy and viruses like Ebola, Marburg and influenza. Eteplirsen is its most advanced experimental drug.

The company planned to file for marketing approval in the first half of 2014, but the Food and Drug Administration told Sarepta in November that that would be premature. That sent the company's stock plummeting. Sarepta expects to finish the design of a late-stage trial of eteplirsen during the first quarter but it isn't sure when it will file for approval.

THE ANALYSIS: Stifel Nicolaus analyst Brian Klein said the company has reported good data for eteplirsen, and he has a positive view of the drug candidate. But he said it's still unclear when the drug might be approved. He kept a "Buy" rating on Sarepta stock with a price target of $21 per share.

SHARE ACTION: Shares of Sarepta gained $6.88, or 34.4 percent, to $26.86 in midday trading. The shares fell 64 percent on Nov. 12 on the FDA news.