US regulators are investigating the death of an 8-year-old boy in Brazil who received Sarepta Therapeutics Inc.’s Elevidys.

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 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.