Gilead Sciences recently announced that the US Food and Drug Administration (FDA) has granted accelerated approval for Hepcludex (bulevirtide-gmod) 8.5 mg for the treatment of adults living with chronic Hepatitis Delta Virus (HDV) infection, making it the first and only approved treatment for HDV in the US.

The FDA granted accelerated approval to Hepcludex based on reductions in HDV RNA and normalisation of alanine aminotransferase (ALT), supported primarily by data from the pivotal, controlled phase 3 MYR301 study. At week 48, the study demonstrated a statistically significant improvement versus the control (delayed treatment) group in a combined virologic and biochemical response. Improvement in disease-related clinical outcomes has not been established. Continued approval for the approved indication may be contingent on verification and description of clinical benefit in a confirmatory trial.

Chronic HDV is considered the most severe form of viral hepatitis and is associated with a markedly higher risk of rapid disease progression, liver failure, and mortality compared with HBV alone. In the US, studies in general populations have estimated that HDV affects between 2 percent and 4 percent of individuals who have chronic Hepatitis B Virus (HBV), representing ~40,000-80,000 people.

Dr. Ira Jacobson, MD, Department of Medicine, NYU Grossman School of Medicine, said, “Hepatitis Delta Virus is associated with rapid progression of liver disease and a high risk of serious or even life-threatening liver-related complications. For patients, an HDV diagnosis means managing two distinct viral liver diseases—hepatitis B and hepatitis D—each contributing to disease progression, monitoring demands, and treatment complexities. The approval of Hepcludex for chronic HDV represents a critical advancement, introducing a long-awaited option that begins to address a significant unmet medical need and has the potential to meaningfully alter the course of this devastating disease for people living with HDV in the United States.”

MYR301 (NCT03852719) evaluated the efficacy and safety of Hepcludex in adults with chronic HDV, with treatment administered for up to 144 weeks followed by 96 weeks of off-treatment follow-up. Hepcludex met its primary endpoint at week 48, with continued treatment, demonstrated sustained efficacy and was generally well tolerated through up to 144 weeks of on-treatment exposure.

Dietmar Berger, MD, PhD, Chief Medical Officer (CMO), Gilead Sciences, said, “The approval of Hepcludex represents a historic milestone for people living with HDV in the United States, marking the first FDA-approved treatment for HDV. This reflects years of close engagement with the FDA and the application of rigorous science to address a serious disease with long-standing unmet need. With Hepcludex, we now have the opportunity to deliver a meaningful clinical advancement that has the potential to change the trajectory of HDV for patients in the US.”