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.

In its own communique issued shortly after the FDA’s, Sarepta elaborated on the situation and confirmed a Roche statement to Bloomberg News that linked the probe to a fatality in Brazil and held that the death of the patient was unrelated to Elevidys itself.

Sarepta Therapeutics Inc. shares rose sharply early Tuesday after US regulators reversed course and recommended that patients who can walk be allowed to take its gene therapy Elevidys again.