Hibsago (bepirovirsen) was approved by the FDA on October 20, 2026 for chronic hepatitis B (adults without cirrhosis, HBsAg 3,000 IU/mL or less), the 47th novel drug approval of 2026 on the FDA's Novel Drug Approvals list.
Verified against: FDA action day October 20, 2026 (FDA press announcement) · Announcement October 20, 2026 (GSK press release) · Goal date October 26, 2026 (Ionis 8-K).
The FDA approved Hibsago, the first antisense oligonucleotide for chronic hepatitis B, six days before its goal date. Per the FDA, 19% of treated patients kept the virus controlled with undetectable HBsAg 24 weeks after stopping all treatment; the label carries a boxed warning for serious liver reactions and low platelet counts.
The FDA's press announcement of October 20, 2026 states that the agency approved Hibsago (bepirovirsen) that day, in combination with existing antiviral therapy, for chronic hepatitis B in certain adults without cirrhosis (FDA, October 20, 2026). GSK announced the approval the same day from Philadelphia (GSK's announcement). The goal date was October 26, 2026 under Priority Review, per Ionis's 8-K exhibit of July 29, 2026 (Ionis 8-K EX-99.1), so the action came 6 days early. The FDA's letter had not been posted on Drugs@FDA when this page was published. Per the FDA, Hibsago is approved for adults without cirrhosis who have taken HBV antiviral therapy for at least six months, have suppressed HBV DNA and have HBsAg of 3,000 IU/mL or less by an FDA-authorized test; it is injected under the skin for up to 24 weeks alongside the existing medicine. Across the two placebo-controlled B-Well trials, 24% of Hibsago patients met the criteria to stop their existing therapy versus none on placebo, and 19% still had the virus under control with undetectable HBsAg 24 weeks after stopping all treatment. The label carries a boxed warning for serious liver reactions and low platelet counts, with warnings for worsening kidney function, vasculitis and injection errors. The FDA also authorized the Roche Elecsys HBsAg II quant II RxDx assay as the companion diagnostic. GSK notes Breakthrough Therapy Designation and the option of self-administration after the first dose. Bepirovirsen was licensed from Ionis.
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Primary source: FDA press announcement, October 20, 2026
FDA record of the action: the FDA approved on October 20, 2026, per FDA press announcement, October 20, 2026 (letter not yet on Drugs@FDA) (FDA notice). The sponsor announced it the same day. Action dates on pdufa.bio come from the FDA's own record, not the press release. Every FDA action we hold, by FDA date: FDA approval letters.
Yes. The FDA approved the application for Hibsago (bepirovirsen) on October 20, 2026, per the FDA's own record. The primary source is linked on this page.
Hibsago (bepirovirsen) is a GSK plc (GSK) program. The FDA decision came on October 20, 2026; the company's own announcement is linked on this page.
Measured over the 120 trading days before the decision (T-120 to T-1), GSK moved -9.6%. That is the recorded price path into this specific event. Historical measurement, not a prediction, and not investment advice.
Yes. The FDA approved Hibsago (bepirovirsen) on October 20, 2026, per the FDA's own press announcement of that day, for chronic hepatitis B in combination with existing antiviral therapy in certain adults without cirrhosis. GSK announced it the same day. It is the first antisense oligonucleotide approved for hepatitis B.
Yes, by 6 days. The goal date was October 26, 2026 (Ionis's 8-K of July 29, 2026, under Priority Review) and the FDA's announcement is dated October 20, 2026.
Per the FDA, across the two placebo-controlled trials 24% of patients on Hibsago met the criteria to stop their existing hepatitis B therapy versus none on placebo, and 19% still had the virus under control with undetectable HBsAg 24 weeks after stopping all treatment. Hibsago carries a boxed warning for serious liver reactions and low platelet counts.