FDA Clears Bepirovirsen for Chronic Hepatitis B in Select Adults
The FDA has approved bepirovirsen (Hibsago) for use with a nucleos(t)ide analogue in certain adults with chronic hepatitis B. Pooled B-Well 1 and 2 results showed functional cure in 19% of treated patients 24 weeks after stopping all therapy, versus 0% with placebo, and 26% among those with baseline HBsAg at or below 1000 IU/mL. The label warns of hepatic flares and thrombocytopenia and calls for liver and platelet monitoring.
The approval covers adults without cirrhosis who have received antiviral treatment for at least six months, maintain suppressed HBV DNA, and have HBsAg levels no higher than 3000 IU/mL. Bepirovirsen is to be used alongside a nucleos(t)ide analogue.
In pooled B-Well 1 and B-Well 2 data, 19% of bepirovirsen recipients met criteria for functional cure 24 weeks after all therapy stopped; placebo recipients did not. Among participants starting with HBsAg at or below 1000 IU/mL, the rate was 26%. The boxed warning flags hepatic flares and thrombocytopenia, requiring liver and platelet monitoring, including weekly platelet checks.
The approval may matter most to adults with chronic hepatitis B who meet the narrow label criteria and have few options for stopping long-term antiviral therapy. Clinicians and patients could face more intensive monitoring because of hepatic flare and platelet risks, which may affect treatment feasibility in some settings. A modest functional-cure rate, concentrated among those with lower HBsAg, may shape expectations and counseling; it may not eliminate the need for ongoing hepatitis B care.