GSK said its antisense oligonucleotide bepirovirsen (also described as bepiroversen/variants in reporting) achieved functional cure in chronic hepatitis B patients in two Phase 3 trials after stopping background nucleos(t)ide therapy. In pooled data, GSK reported a functional cure rate of about one-fifth across both studies. The readout described in one report cites 20% functional cure in B-Well 1 and 19% in B-Well 2 at week 72, with none in placebo arms meeting functional cure criteria after fixed-duration treatment and discontinuation of NA therapy. NEJM publication details included adverse-event rates and the types of grade 3 events observed. The company framed the results as a potential step-change in chronic HBV treatment, where a functional cure can reduce long-term complications including cirrhosis, liver failure, and liver cancer risk. Clinical and regulatory next steps will center on evidence packages for regulators, building on the Phase 3 design and the functional-cure endpoint used in the trials.