FDA approves GSK-Ionis antisense drug Hibsago, opening functional-cure market for hepatitis B

The U.S. Food and Drug Administration has granted approval to Hibsago (bepirovirsen), a partnership product of GSK and Ionis Pharmaceuticals, marking the first antisense oligonucleotide cleared for chronic hepatitis B. The therapy is designed to achieve a functional cure by reducing viral levels to undetectable amounts.

The decision creates a new market segment for other biopharma firms, with companies such as Gilead Sciences, Arrowhead Pharmaceuticals and Aligos Therapeutics now positioned to develop comparable or improved treatments.

Analysts at H.C. Wainwright note that the approval resolves previous doubts about whether a finite treatment course can deliver lasting off‑treatment responses, boosting confidence in the emerging functional‑cure space.