Shares of Sarepta Therapeutics Inc. dropped 26.3 percent Tuesday, the day after an influential Food and Drug Administration advisory committee ­narrowly voted against recommending approval of the company’s experimental drug.

The advisory panel’s vote was nonbinding, and the FDA is scheduled to decide by May 26 whether to approve Sarepta’s treatment for Duchenne muscular dystrophy, a fatal muscle-wasting disease. The agency usually follows the guidance of its advisory committee, but there have been cases where it hasn’t.

In a statement, Sarepta’s chief executive officer thanked the hundreds of ­Duchenne ­patients and family members who attended the day-long ­advisory committee meeting in Hyattsville, Md., to support the drug candidate, called Eteplirsen.

“We appreciated the opportunity to present our data to the advisory committee panel and will continue to work with FDA as they complete their review of the Eteplirsen new drug application,’’ Sarepta chief executive Edward Kaye said in the ­statement. “Today more than ­ever, we remain committed to our mission of bringing a treatment to the ­Duchenne community.’’

Despite the testimony of patients who said they were helped by the drug, a majority of the advisory committee, made up of medical experts from across the country, determined Sarepta’s clinical trial was flawed and made it difficult to determine whether the drug was effective in slowing the ­disease’s progression.

Sarepta’s stock fell $3.93 a share to $11.02 a share on the Nasdaq exchange.

Robert Weisman can be reached at robert.weisman@globe.com. Follow him on Twitter @GlobeRobW.