GlaxoSmithKline PLC's bepirovirsen injection for chronic hepatitis B virus (HBV) infection has been proposed for priority review by China's Center for Drug Evaluation (CDE). The therapy is intended for a finite treatment course in adult non-cirrhotic patients with chronic HBV who are currently receiving nucleos(t)ide analogue therapy and have HBsAg levels ≤3000 IU/mL. This development follows the drug's previous designation as a breakthrough therapy in China, bringing this potential first-in-class antisense oligonucleotide treatment, which aims for a functional cure for hepatitis B, closer to availability for Chinese patients. Bepirovirsen is an investigational antisense oligonucleotide (ASO) therapy developed through a collaboration between GSK and Ionis Pharmaceuticals. If approved, it would become the first antiviral therapy globally capable of achieving a functional cure for HBV after just a six-month finite treatment course. GSK plans to initiate global regulatory submissions in the first quarter of 2026, with the drug already under review for approval in Japan. Bepirovirsen features a triple mechanism of action designed to target and degrade the virus's genetic material (RNA), potentially enabling a patient's immune system to regain control over the viral infection. It works by suppressing viral DNA replication, reducing HBsAg levels in the blood, and activating the immune system to increase the likelihood of a sustained response. GSK licensed bepirovirsen from Ionis Pharmaceuticals and is co-developing the drug. In January 2026, GSK announced positive results from two pivotal Phase 3 clinical trials, B-Well 1 and B-Well 2, evaluating bepirovirsen for chronic hepatitis B. Both studies met their primary endpoints, demonstrating statistically significant and clinically meaningful rates of functional cure. The B-Well trials were global, multicenter, randomized, double-blind, placebo-controlled studies designed to assess the efficacy, safety, pharmacokinetics, and durability of functional cure with bepirovirsen in chronic HBV patients on nucleos(t)ide analogue therapy with baseline HBsAg ≤3000 IU/mL. The primary endpoint was the proportion of patients achieving functional cure, defined as HBsAg loss with undetectable HBV DNA for at least 24 weeks after the end of the finite treatment course. A key secondary endpoint assessed functional cure in patients with baseline HBsAg ≤1000 IU/mL. Analysis confirmed the trials met the primary endpoint, with bepirovirsen plus standard of care significantly increasing functional cure rates compared to standard of care alone. Statistical significance was achieved across all endpoints, with a stronger effect observed in the patient subgroup with baseline HBsAg ≤1000 IU/mL. The therapy demonstrated a safety and tolerability profile consistent with previous studies.