The U.S. Food and Drug Administration ( FDA) has placed an immediate clinical hold on Sarepta Therapeutics' investigational gene therapy trials for limb girdle muscular dystrophy following three patient deaths potentially linked to the company's treatments.

In a highly unusual move, Cambridge-based Sarepta said late Friday won’t comply with a request from the Food and Drug Administration to halt all shipments of its gene therapy.

Shares of Sarepta Therapeutics declined 17% in early trading on Friday after another patient who had received an experimental gene therapy died, deepening investor concerns over the use of the company's treatments.