Sarepta shares spike on upbeat results from DMD extension study

Shares of Sarepta ($SRPT) were boosted this morning after the biotech announced that it reaped another round of promising results from a closely-watched Phase IIb study of its experimental treatment for Duchenne muscular dystrophy.

At the 84-week mark, boys taking eteplirsen continued to easily beat out the placebo arm in terms of walking distance, registering a 46.4-meter improvement in a 6-minute walk test. There was a decline of less than 6% in walking distance in the drug arm, a stable result for the boys. And at a time when boys with this disease are completely losing their ability to walk, one recovered from an injury and was back up on his feet, ready to contribute to future extension study data.

Sarepta's shares were trading just under the $40 mark this morning, an 849% increase over the past year.

A large group of investors have been paying rapt attention to every step of this trial, with many convinced that the FDA can be persuaded to step in and provide an early approval for this treatment. But Sarepta only recruited a small number of boys for this study, raising concerns that the FDA might well want to wait and see results from a much larger trial before it decides on marketing approval. Sarepta has been racing against GlaxoSmithKline ($GSK) and Prosensa, partnered on a late-stage study for a competing therapy. 

CEO Chris Garabedian, meanwhile, is staying upbeat. 

President and CEO Chris Garabedian

"We now have demonstrated stability of walking for over a year and a half in the original eteplirsen treatment cohort in boys who are now 11 years old on average, an age when many DMD boys have lost the ability to walk," said Garabedian in a statement. "In addition, the placebo/delayed-treatment cohort, which has now received eteplirsen for over a year, has demonstrated a stabilization in walking ability for 48 weeks compared with the precipitous decline observed earlier in the study before dystrophin was confirmed in these patients. Overall, we believe the data across all treatment cohorts are remarkably consistent and continue to support eteplirsen as a potential treatment option in DMD."

- here's the press release