The Food and Drug Administration approved bepirovirsen under the brand name Hibsago on October 20, 2026, introducing a finite therapy for chronic hepatitis B. Patients who respond can halt their medications while keeping viral levels undetectable in the blood, moving away from continuous antiviral pills.
Wendy Carter, Acting Director at the FDA's Office of Infectious Diseases, stated that "Hibsago provides a new treatment approach that gives some patients the possibility of maintaining control of the virus after all chronic HBV treatment has ended."
In two phase 3 clinical trials published in the New England Journal of Medicine, a six-month course produced a functional cure in 19 percent of participants—233 out of 1,220 people—compared to zero out of 614 on placebo. Among those who responded, viral levels remained undetectable for at least 24 weeks after finishing all medication.
Administration and Monitoring
The therapy consists of weekly injections alongside oral antivirals, which patients stop once their viral load becomes undetectable. Patients may self-administer the weekly shots after an initial supervised dose. Participants entering treatment with lower baseline amounts of a specific viral protein showed higher response rates.
Because trial participants experienced side effects such as liver inflammation, the FDA requires periodic blood tests to track liver health. Small amounts of the virus remain in the body, and researchers have not yet confirmed whether the functional cure lasts for multiple years. Patients can consult their healthcare provider to check their eligibility and viral protein levels.
