Sarepta Shares Drop After FDA Asks for More Data on Elevidys

The Food and Drug Administration won’t sign off on Sarepta Therapeutics Inc. bringing its controversial gene therapy back to the market until the company can persuade US regulators that it won’t cause more deaths, according to an official familiar with the situation.

The company’s stock fell as much as 21% on Thursday and has lost around half its value over the past week.