GSK reported two Phase 3 trials of the antisense oligonucleotide bepirovirsen showing functional cure after discontinuing background nucleos(t)ide therapy. In NEJM-published results, 20% (B-Well 1) and 19% (B-Well 2) of noncirrhotic chronic hepatitis B patients met the study’s functional cure definition at week 72, versus none on placebo arms. After fixed-duration bepirovirsen, patients stopped nucleos(t)ide therapy at week 48, with outcomes assessed through week 72. GSK also reported a higher overall adverse-event rate in bepirovirsen groups (91% vs 73%) and more grade 3+ alanine aminotransferase elevations (6% vs placebo’s 3%), alongside serious adverse events of 7% vs 4%. A separate GSK-focused update framed the results as clearing roughly one-fifth of treated patients, positioning bepirovirsen as a potential new finite-duration option in a field where most therapies require long-term suppression. Regulators are reviewing the broader bepirovirsen evidence package across multiple markets, as GSK continues to advance its “off-therapy” strategy.