When three patients die after taking a cutting-edge drug, most companies hit the brakes. Not Sarepta Therapeutics. The Massachusetts-based biotech company is under fire for refusing a request from the U.

Drugmaker Sarepta Therapeutics says it won’t comply with a request from U.S. regulators to halt all shipments of its gene therapy.

Second patient death from liver failure after Sarepta's Elevidys gene therapy triggers FDA investigation. Stock crashes 41% as company halts non-ambulatory patient treatments.