Sarepta jumps on fresh optimism for an early approval

Sarepta CEO Chris Garabedian

Sarepta's ($SRPT) up-and-down quest to get eteplirsen in the hands of patients with Duchenne muscular dystrophy is looking a little sunnier thanks to more promising data and an optimistic reading of some FDA tea leaves, news that sent the biotech's shares up as much as 35% on Thursday.

In 120-week results from Sarepta's ongoing Phase IIb study, eteplirsen demonstrated continued ability in helping boys with the muscle-destroying disease perform well on a 6-minute walk test. Patients on the drug were able to walk 64.9 meters farther than the placebo group, stable results that Sarepta said confirm the drug's benefits in a rare fatal disease.

The latest data helped buoy Sarepta's shares as high as $27 on Thursday, a 35% jump over their previous close but still a mere fraction of their value before the FDA seemed to throw dirt on hopes for an early approval of eteplirsen back in November. Sarepta had believed it could file an NDA without embarking on Phase III trial for the drug, but, in light of GlaxoSmithKline ($GSK) and Prosensa's ($RNA) late-stage failure with the similar drisapersen, the agency began to reconsider that possibility, the company said.

But now the ever-cryptic FDA has signaled that it is yet to make anything resembling a final decision on eteplirsen's early-approval potential, and Sarepta CEO Chris Garabedian told investors at the J.P. Morgan Healthcare conference that the company is yet to receive the minutes from its last meeting with the agency, something analysts interpret as a sign that eteplirsen is very much an open case for regulators.

"We now have more than two years of data with eteplirsen on the 6-minute walk test, the most accepted clinical outcome measure in Duchenne muscular dystrophy, which demonstrates walking stability that we believe would not be expected based on the natural history of this disease over the same time period," Garabedian said in a statement. "We also now have over two years of safety data with eteplirsen with no treatment-related serious adverse events which is important when considering the need for lifelong treatment of this disease."

Whether that's enough for the FDA remains to be seen.

- check out the results