The U.S. Food and Drug Administration today announced it is taking action to approve new labeling submitted by the company that includes the addition of a Boxed Warning, the agency’s most prominent safety warning, to Elevidys (delandistrogene moxeparvovec-rokl), and that the indication section of the labeling limits the therapy’s indication to ambulatory patients four years of age and older with Duchenne muscular dystrophy (DMD). These actions follow reports of fatal acute liver failure in non-ambulatory patients treated with the product.  

Elevidys is an AAVrh74 adeno-associated virus (AAV) vector-based gene therapy approved for the treatment of DMD in certain patients. In June 2025, the FDA issued a CBER Safety Communication following two reports of fatal acute liver failure in non-ambulatory pediatric males with DMD after receiving Elevidys. In response, the manufacturer voluntarily paused distribution of Elevidys for use in non-ambulatory patients.  

In both fatal cases, patients developed markedly elevated liver enzymes and required hospitalization within two months of Elevidys infusion. An additional serious, non-fatal case of acute liver injury has involved complications such as mesenteric vein thrombosis, bowel ischemia and necrosis, and portal hypertension.  

After a comprehensive evaluation of the available safety data, FDA has now approved substantial labeling revisions for Elevidys, including:  

• Addition of a Boxed Warning describing the risk of serious liver injury and acute liver failure, including fatal outcomes;  
• Limiting the indication to ambulatory patients with DMD who are 4 years of age and older with a confirmed mutation in the DMD gene;  
• Removal of the indication for non-ambulatory patients with DMD;  
• Addition of a Limitations of Use statement to guide clinical decision-making;  
• Updates to the Warnings and Precautions, Dosage and Administration, Adverse Reactions, Use in Specific Populations, Clinical Studies, and Patient Counseling Information sections; and  
• Inclusion of a new Medication Guide for patients and caregivers.  

Key Safety Information for Patients and Health Care Providers  

The revised labeling includes specific safety information and monitoring recommendations:  

• Liver monitoring: Weekly liver function tests are advised for at least three months after treatment. Patients should remain near an appropriate medical facility for at least two months post-infusion.  
• Prompt medical attention: Patients should contact their health care provider immediately if they experience yellowing of the skin or eyes, if they miss or vomit corticosteroid doses, or if the patient experiences a change in mental status.  
• Infection risk: Corticosteroid therapy may suppress immune function, increasing susceptibility to infections and serious complications including death.  
• Cardiac monitoring: Weekly testing for cardiac injury (troponin-I) is advised for one month following treatment.  
• Contraindications: Elevidys should not be used in patients with deletions involving DMD exons 8 and/or 9.   
• Limitations of Use: Elevidys is not recommended in patients with preexisting liver impairment, recent vaccinations, or recent/active infections.  

Postmarketing Requirements  

The FDA is requiring the manufacturer to conduct a postmarketing observational study to further assess the risk of serious liver injury. The study will enroll approximately 200 patients with DMD and follow them for at least 12 months after administration of Elevidys, with periodic liver function assessments.  

Reporting Adverse Events  

Health care professionals and patients are encouraged to report adverse events, including cases of liver injury, to the FDA MedWatch program:  

• Online at www.fda.gov/medwatch
• By phone: 1-800-FDA-1088  

Adverse events may also be reported to Sarepta Therapeutics, Inc. at 1-888-727-3782.  

The FDA remains committed to the continued evaluation of the safety and effectiveness of gene therapies and will provide updates as new information becomes available.  

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