FDA Press Releases·Oct 20, 2026, 3:40 PM ET

FDA Approves First-of-Its-Kind Chronic Hepatitis B Treatment

The FDA approved Hibsago (bepirovirsen) injection on October 20, 2026, as the first antisense oligonucleotide for chronic hepatitis B virus (HBV) infection in certain adults without cirrhosis.
Hibsago is indicated for adults taking existing antiviral therapy for at least six months, with suppressed HBV levels & HBsAg levels of 3,000 IU/mL or less.
The treatment involves subcutaneous injections for up to 24 weeks alongside existing medication, which patients must continue for at least 24 weeks after the final Hibsago dose.
Clinical trials showed 24% of Hibsago recipients met criteria to stop existing therapy compared to 0% for placebo, with 19% maintaining viral control & undetectable HBsAg 24 weeks after stopping all treatment.
A companion diagnostic device, the Roche Elecsys HBsAg II quant II RxDx assay, was authorized to assist in patient selection & monitoring.
Hibsago carries a boxed warning for serious liver reactions & low platelet counts, along with warnings for worsening kidney function, inflammatory adverse reactions, & administration risks.
The most common side effects include injection site reactions, fever, fatigue, & headache.
GSK plc received the approval following Fast Track, Breakthrough Therapy designations, & Priority Review.