(Reuters) -The U.S. Food and Drug Administration said on Friday it was investigating the death of an eight-year-old boy who received Sarepta Therapeutics' muscular disorder gene therapy Elevidys.

The death occurred on June 7, the agency said, sending shares of the company down more than 3% in extended trading.

The patient with Duchenne muscular dystrophy, who died in Brazil, was treated with Elevidys but was not a participant in a clinical trial, Roche, which partners with Sarepta outside the U.S., told Reuters in an email.

The reporting physician has assessed the death as unrelated to treatment with the gene therapy, Roche said, adding that the death was reported to the health authorities as required per local regulations, and that it was continuing to gather and analyze the information from this event.

Sarepta has come under intense regulatory scrutiny after two non-ambulatory teenage boys died due to acute liver failure associated with Elevidys, and a 51-year-old man who had received its experimental gene therapy SRP-9004 died from the same condition.

Late on Monday, the company said it would comply with a request from the FDA to pause all shipments of Elevidys in the United States. Its partner Roche also paused Elevidys shipments in some countries outside the U.S. later.

The FDA's request had come after the company disclosed the death of the patient on SRP-9004.

(Reporting by Mariam Sunny and Kamal Choudhury in Bengaluru; Editing by Devika Syamnath)