IONIS PHARMACEUTICALS INC 8-K

What Happened Ionis Pharmaceuticals announced on January 7, 2026 that partner GSK reported positive results from two pivotal Phase 3 studies (B‑Well 1 and B‑Well 2) of bepirovirsen, an investigational antisense oligonucleotide for chronic hepatitis B (CHB). The studies enrolled over 1,800 patients across 29 countries and met their primary endpoint: bepirovirsen plus standard of care produced a statistically significant and clinically meaningful functional cure rate versus standard of care alone. The safety and tolerability profile was described as acceptable and consistent with prior studies.

Full study results will be submitted for presentation at an upcoming scientific congress, prepared for publication in a peer‑reviewed journal, and used to support regulatory submissions worldwide. Bepirovirsen was licensed to GSK in 2019; it has received multiple regulatory designations, including FDA Fast Track (U.S.), Breakthrough Therapy (China) and SENKU (Japan).

Key Details

• Studies: B‑Well 1 & B‑Well 2 — >1,800 patients in 29 countries; primary endpoint met (functional cure).
• Commercial terms: Ionis eligible for up to $150 million in additional regulatory and sales milestones plus tiered royalties of 10–12% on net sales.
• Timeline/next steps: Full results to be presented/published and used to support global regulatory submissions.
• Regulatory recognition: FDA Fast Track (U.S.), Breakthrough Therapy (China), SENKU (Japan).

Why It Matters For investors, the Phase 3 success is a material clinical milestone for a late‑stage asset originally developed by Ionis and licensed to GSK. If regulators approve bepirovirsen, it could become a finite, six‑month therapeutic option for CHB — a disease affecting over 250 million people worldwide where current treatments typically require lifelong therapy and yield low functional cure rates. Financially, Ionis stands to receive additional milestone payments and ongoing royalties (10–12%) on net sales, which could add meaningful revenue if the drug is approved and commercialized. The company will use these results in regulatory filings; however, Ionis includes the usual forward‑looking statement cautions about risks and uncertainties.