FDA Grants First-Ever Approval for Hepatitis Delta Treatment with Gilead's Hepcludex
核心洞察
The FDA has granted accelerated approval to Gilead's Hepcludex (bulevirtide-gmod (搜索)) as the first and only approved treatment for chronic hepatitis delta virus (搜索) (HDV (搜索)) infection in the United States.
The approval is based on Phase 3 MYR301 study data showing statistically significant improvements in combined virologic and biochemical response at Week 48 compared to delayed treatment control.
Chronic HDV (搜索) affects an estimated 40,000-80,000 Americans and is considered the most severe form of viral hepatitis with mortality rates as high as 50% within five years in cirrhotic patients.
The U.S. Food and Drug Administration has granted accelerated approval to Gilead Sciences' Hepcludex (bulevirtide-gmod (搜索)) 8.5 mg, marking a historic milestone as the first and only approved treatment for chronic hepatitis delta virus (搜索) (HDV (搜索)) infection in the United States. The approval addresses a critical unmet medical need for a patient population that has long lacked therapeutic options.
Pivotal Trial Results Drive Approval
The FDA's accelerated approval is based on data from the pivotal Phase 3 MYR301 study (NCT03852719), which evaluated Hepcludex in adults with chronic HDV (搜索) over 144 weeks of treatment followed by 96 weeks of off-treatment follow-up. At Week 48, the study demonstrated a statistically significant improvement versus the control (delayed treatment) group in a combined virologic and biochemical response, meeting its primary endpoint.
The approval specifically relies on reductions in HDV (搜索) RNA and normalization of alanine aminotransferase (ALT) levels. However, the FDA notes that improvement in disease-related clinical outcomes has not been established, and continued approval may be contingent on verification and description of clinical benefit in a confirmatory trial.
Addressing the Most Severe Form of Viral Hepatitis
Chronic HDV (搜索) represents the most severe form of viral hepatitis, occurring only as a co-infection in individuals with chronic hepatitis B virus (搜索) (HBV (搜索)). The disease is associated with markedly higher risks of rapid disease progression, liver failure (搜索), and mortality compared to HBV infection alone. In cirrhotic patients, HDV can have mortality rates as high as 50% within five years.
"Hepatitis delta virus is associated with rapid progression of liver disease and a high risk of serious or even life-threatening liver-related complications," said Dr. Ira Jacobson from NYU Grossman School of Medicine (搜索). "For patients, an HDV (搜索) diagnosis means managing two distinct viral liver diseases—hepatitis B and hepatitis D—each contributing to disease progression, monitoring demands, and treatment complexities."
In the United States, studies estimate that HDV (搜索) affects between 2% and 4% of individuals with chronic HBV (搜索), representing approximately 40,000-80,000 people. Globally, at least 12 million people are currently co-infected with HDV and HBV.
First-in-Class Mechanism of Action
Hepcludex is a first-in-class entry inhibitor that works by blocking the entry of both HDV (搜索) and HBV (搜索) into liver cells, addressing a key step in the viral lifecycle. The treatment is administered as an 8.5 mg once-daily subcutaneous injection and should be continued as long as it is associated with a response to treatment, though the optimal treatment duration remains unknown.
"The approval of Hepcludex represents a historic milestone for people living with HDV (搜索) in the United States, marking the first FDA-approved treatment for HDV," said Dietmar Berger, Chief Medical Officer at Gilead Sciences. "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."
Safety Profile and Monitoring Requirements
The most common adverse reactions observed in clinical trials (incidence ≥10%) were injection site reactions, headache, abdominal pain, fatigue, and pruritus. The drug carries a boxed warning for posttreatment severe acute exacerbations of hepatitis D and B, particularly in patients with cirrhosis (搜索) who may be at increased risk of more severe flares or progression to hepatic decompensation.
Healthcare providers must monitor hepatic function closely with both clinical and laboratory follow-up, including HBV (搜索) DNA and HDV (搜索) RNA viral load, for at least six months in patients who discontinue Hepcludex. The drug also carries warnings for hypersensitivity reactions, including anaphylaxis.
Global Approval Status and Access
While the 8.5 mg formulation has received FDA approval for the U.S. market, bulevirtide 2 mg is already approved for use in the European Economic Area and other countries globally for treating chronic HDV (搜索). Gilead's Support Path Program will provide information and resources to help patients and healthcare professionals understand coverage and financial options for the treatment.
As part of the accelerated approval pathway, Gilead has committed to conducting a confirmatory long-term outcomes study in people living with chronic HDV (搜索), which has already been initiated. The company's continued approval may depend on verification of clinical benefit in this confirmatory trial.