Sarepta Therapeutics announced it has laid off more than one-third of its workforce, a drastic cost-cutting move following the deaths of two teenagers administered its gene therapy for Duchenne muscular dystrophy.

On a conference call, CEO Doug Ingram said the decision to cut 36% of the company's staff and halt several drug programs was essential to ensuring Sarepta's "long-term viability."

Sarepta Therapeutics is laying off 500 staffers, or 36% of its workforce, as part of a strategic restructuring aiming to save $400 million annually. | Sarepta Therapeutics has laid off 500 staffers, or 36% of its workforce,

A filing with the state details the Columbus job cuts for a biotech cutting more than one-third of its workforce.

A Cambridge-based company developing gene therapies for rare diseases is laying off more than a third of its workforce.

The drop comes the day after the drugmaker said it would add a so-called black-box warning to its gene therapy Elevidys after two teenage boys receiving the treatment died earlier this year.

Sarepta rebuffed a call from the Food and Drug Administration to halt all shipments of its gene therapy for Duchenne muscular dystrophy over safety issues, even as patients and investors expressed growing concern about the company’s decision-making.