The FDA approved a first hepatitis B treatment that may let some patients stop all medication

On October 20, 2026, the Food and Drug Administration approved Hibsago (bepirovirsen) for certain adults with chronic hepatitis B who do not have cirrhosis. It is the first antisense oligonucleotide the agency has approved for this infection. A patient has to have been on antiviral medicine for at least six months, with the virus already suppressed and a hepatitis B surface antigen level of 3,000 IU/mL or less on an authorized test. Hibsago is injected under the skin for up to 24 weeks, alongside that existing medicine. The older medicine continues for at least 24 weeks after the last injection. Only then, and only if health and lab results meet the label, may some patients stop.

Two trials compared Hibsago with a placebo. Across them, 24 percent of people who received Hibsago met the requirements to stop their existing antiviral, and none of the placebo patients did. Twenty-four weeks after all hepatitis B treatment had ended, 19 percent of the Hibsago group still had the virus under control, and the surface antigen could not be detected in their blood. That is a measured result in a selected group. It is not a cure for chronic hepatitis B in general, and it does not mean most people on treatment can quit.

Hibsago carries a boxed warning for serious liver reactions and for low platelet counts, which can raise the risk of life-threatening bleeding. The label also warns about worsening kidney function, serious inflammatory reactions such as vasculitis, and harm if the shot is not given correctly. Patients need blood tests and follow-up before and during treatment. The most common side effects, aside from laboratory changes, were injection-site reactions, fever, fatigue, and headache. The FDA also authorized a Roche blood test to help choose and monitor patients. The approval went to GSK.