(Reuters) - Shares of Sarepta Therapeutics Inc (SRPT.O) opened 6.9 percent higher after GlaxoSmithKline Plc (GSK.L) reported disappointing clinical data for a rival therapy to Sarepta's experimental muscle disorder drug.
Analysts at brokerage house Robert W. Baird said the data may put Sarepta ahead of competition in the race to market the first drug to treat a rare, muscle-wasting disorder called Duchenne Muscular Dystrophy.
The disease, which affects about one in every 3,500 newborn boys, has recently attracted interest from multiple drugmakers.
Sarepta and Glaxo, which is developing a competing drug with Dutch drugmaker Prosensa Holding NV RNA.O, have been seen as ahead of the pack so far.
However, Baird analyst Brian Skorney said on Friday the latest clinical data from Glaxo's drug, drisapersen, shows new clinical, regulatory and commercial risk for its product.
Shares in Sarepta jumped to $34.25 at the open on the Nasdaq, before easing back a little to $33.95. Prosensa shares fell about 9 percent to $26.11.
Data released on Glaxo's website on Thursday, indicated that a substantial number of patients treated with the targeted dose of the drug may not be getting a meaningful drug effect, Skorney said.
"We believe this introduces new clinical, regulatory and commercial risk for this competitive drug, which should benefit Sarepta given the more favorable therapeutic index that eteplirsen appears to have," Skorney said.
The analyst reiterated his "outperform" rating on Sarepta stock, saying he continues to believe that drisapersen's safety profile is worse than eteplirsen's.
Reporting by Zeba Siddiqui in Bangalore; Editing by Rodney Joyce