Elevidys Side Effects Suspected in Liver Failure, Death of Duchenne Muscular Dystrophy Patient

Controversial gene therapy treatment appears to be linked to a teenager’s death from acute liver failure.

The death of a 16-year-old boy has been linked to potential side effects of the gene therapy treatment Elevidys, less than two years after the drug’s controversial approval by the U.S. Food and Drug Administration (FDA).

Elevidys (delandistrogene moxeparvovec-rokl) is a single-dose gene therapy treatment designed and manufactured by Sarepta Therapeutics, which is approved to treat Duchenne muscular dystrophy (DMD) in patients who are over 4 years old. DMD is a genetic disorder that causes muscle weakness and degeneration due to a lack of the protein dystrophin, which is needed for proper muscle functioning.

The FDA approved Elevidys as the only gene therapy treatment for DMD in June 2023. However, during the course of the approval process, the FDA director of the Center for Biologics Evaluation and Research, Dr. Peter Marks, overruled multiple internal objections to grant initial accelerated approval for the drug in 2023.

The following year, this approval was expanded to cover most U.S. patients suffering from Duchenne muscular dystrophy, leading to concerns about potential side effects of Elevidys, and whether the medication had been established as safe and effective.

In a press release (PDF) issued on March 18, Sarepta Therapeutics acknowledged that the company discovered that an Elevidys patient passed away at the age of 16 years old, due to acute liver failure. This is the first instance of death related to the gene therapy treatment.

However, Sarepta pointed out that the treating physician in this case had diagnosed the patient with a cytomegalovirus (CMV) infection, which may have been a contributing factor in the teen’s death. CMV can cause CMV hepatitis, which is a condition where the virus infects and damages the liver. 

Serious liver injuries had been previously reported with Elevidys, in which liver enzymes had become elevated within eight weeks of treatment. For this reason, the manufacturer has noted that patients with preexisting liver conditions, hepatitis or acute liver disease could be at a higher risk of severe injury.

The company has recommended in the past that liver enzyme tests be administered before a patient is treated with Elevidys, and that liver monitoring continues for the first three months after the drug’s infusion. 

More than 800 patients have received Elevidys in either clinical trials or as a prescribed therapy. The possibility of acute liver failure leading to death as a side effect of the therapy had never been previously reported.

“Patient safety and well-being are Sarepta’s top priority,” the company said in its press release. “We continue to gather and analyze the information from this event. The event has been reported to the relevant health authorities and Sarepta intends to update the prescribing information to appropriately represent this event.”

Other potential Elevidys side effects include immune-mediated myositis, myocarditis, and other adverse health reactions like vomiting, nausea, pyrexia and thrombocytopenia.