WASHINGTON (AP) — Shares of Sarepta Therapeutics plunged Monday after the biotech drugmaker reported a second death in connection with its gene therapy for muscular dystrophy.

Duchenne muscular dystrophy patient died after being treated with the gene therapy delandistrogene moxeparvovec (Elevidys), Sarepta Therapeutics said Sunday. Like the first case reported, this patient developed acute liver failure (ALF) that resulted in death.

Sarepta Therapeutics said a second patient had died after receiving its $3.2 million gene therapy to treat Duchenne muscular dystrophy.