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.

An unusual public feud between the Food and Drug Administration and a maker of gene therapies for rare diseases could test the Trump administration's willingness to pull certain approved drugs from the market over safety concerns.