Medical Week Daily Pro · Approval explained
Hibsago (bepirovirsen): what FDA's first antisense drug for chronic hepatitis B does, who it is for, and what the numbers really say
On 20 October 2026 FDA approved a 24-week add-on injection that let a minority of patients stop all hepatitis B medicine. Here is the approval, line by line.
Published 2026-10-27 · 6 min read
The one-paragraph version
On 20 October 2026 the U.S. Food and Drug Administration approved Hibsago (bepirovirsen) injection, made by GSK, for certain adults with chronic hepatitis B who do not have cirrhosis [1]. It is not a replacement for the antiviral tablets most patients already take. It is given on top of that medicine for up to 24 weeks, with the goal that some patients can later stop all hepatitis B treatment and still keep the virus under control [1]. FDA calls it the first approved antisense oligonucleotide for chronic hepatitis B [1]. In the two placebo-controlled trials FDA describes, 24% of patients on Hibsago met the requirements to stop their existing medicine, compared with none on placebo, and 19% still had the virus under control, with no detectable hepatitis B surface antigen, 24 weeks after stopping everything [1]. It carries a boxed warning for serious liver reactions and low platelet counts [1].
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