FDA Safety Communication – November 14, 2025

Summary of the Issue

In June 2025, FDA issued a safety communication, “FDA Investigating Deaths Due to Acute Liver Failure in Non-ambulatory Duchenne Muscular Dystrophy Patients Following ELEVIDYS,” to provide information on two reports of fatal acute liver failure following treatment with Elevidys (delandistrogene moxeparvovec-rokl) of non-ambulatory pediatric male patients with Duchenne Muscular Dystrophy (DMD). FDA also listed hepatotoxicity-associated fatalities in non-ambulatory patients with DMD as a potential signal of serious risk/new safety information for Elevidys, identified by FDA Adverse Event Reporting System (FAERS) in the January - March 2025 quarterly report. Since June 2025, the manufacturer voluntarily suspended U.S. distribution of Elevidys for treatment of non-ambulatory DMD patients.

Elevidys is an AAVrh74 adeno-associated virus vector-based gene therapy for the treatment of DMD. Fatal reports of acute liver failure were received from clinical trial and postmarketing data. The patients presented with elevated transaminases and were hospitalized less than two months after treatment with Elevidys. Life-threatening mesenteric vein thrombosis, complicated by bowel ischemia and necrosis, and portal hypertension has also been reported following serious non-fatal acute liver injury associated with Elevidys in a non-ambulatory DMD patient.

FDA has completed a review of the safety data and, following FDA’s issuance of a safety labeling change notification letter, has approved the following safety labeling changes to include new safety information on the risk of serious liver injury and acute liver failure including fatal outcomes: addition of Boxed Warning; updates to the Indications and Usage including addition of Limitations of Use; Warnings and Precautions; Dosage and Administration; Adverse Reactions – Postmarketing Experience; Use in Specific Populations; Clinical Studies; Patient Counseling Information sections of the prescribing information, and addition of a Medication Guide.

Notably, the revised Indications and Usage limits the indication to ambulatory DMD patients who are 4 years of age or older and have a confirmed mutation in the DMD gene.  The indication for use in the non-ambulatory population is no longer included in the Indications and Usage section of the labeling, and use in the non-ambulatory population is no longer licensed under the BLA.  Therefore, Elevidys is only approved for use in ambulatory DMD patients 4 years of age and older.  There is now a Limitations of Use section to emphasize careful consideration of appropriateness and timing of treatment. FDA concluded that addition of a Boxed Warning was warranted to highlight the risk of serious liver injury and acute liver failure and alert healthcare providers to obtain prompt consultation with a specialist if acute serious liver injury or impending acute liver failure is suspected, and instruct patients to maintain proximity to an appropriate healthcare facility, as determined by the healthcare provider, for at least 2 months following Elevidys infusion. 

Postmarketing study and safety monitoring

Based on the new safety information on the risk of serious liver injury and acute liver failure, FDA has made the determination that a postmarketing requirement (PMR) under section 505(o) of the Federal Food, Drug, and Cosmetic Act (FDCA) is needed to assess this serious risk. FDA has required the manufacturer to conduct a postmarketing, prospective, observational study in 200 patients with DMD.  The enrolled patients will be followed for at least 12 months after product administration.  The study design will include monitoring (at pre-specified intervals) for hepatotoxicity with adequate testing strategies.

Continuous monitoring and assessment of the safety of all biologics, including Elevidys, is an FDA priority and we remain committed to informing the public when we learn new information about these products.  
More information describing FDA’s regulatory action is available here: FDA Approves New Safety Warning and Revised Indication that Limits Use for Elevidys Following Reports of Fatal Liver Injury.

To report suspected adverse events including liver injury, contact the FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.