Sarepta Therapeutics faces an "arduous path” to try to get its gene therapy for Duchenne muscular dystrophy back onto the market, a senior FDA official told STAT.

After the FDA request, Cambridge, Massachusetts-based Sarepta said in a statement that it will continue to ship the therapy to ambulatory people but maintain a halt it implemented June 15 for non-ambulatory patients after reporting to the FDA a case of acute liver failure in a patient who could not walk.

Sarepta faces FDA scrutiny over Elevidys as analysts downgrade stock and warn of long-term debt risks amid market uncertainty.

Sarepta stock tanked Friday after a new patient death was uncovered, spurring an FDA request to halt shipments of an unrelated drug.

A third patient has died this year after getting a gene therapy from Sarepta Therapeutics Inc., raising questions about the company’s transparency and adding more pressure on US regulators to decide on the future of the company’s most important drug.

The death of a 51-year-old man in the study follows two other deaths of Duchenne patients treated with Sarepta’s marketed gene therapy Elevidys.

The FDA will request Sarepta Therapeutics stop all shipments of Elevidys, its gene therapy for Duchenne muscular dystrophy, following two deaths tied to the product.