BOSTON PHARMACEUTICALS

GSK has agreed to acquire efimosfermin alfa, a phase III-ready liver disease drug, from Boston Pharmaceuticals in a deal worth up to $2 billion.

GSK has agreed to acquire efimosfermin alfa from Boston Pharmaceuticals for $1.2 billion upfront, with potential additional milestone payments of $800 million, strengthening its hepatology pipeline.

• Boston Pharmaceuticals' efimosfermin alfa demonstrated statistically significant fibrosis improvement in MASH patients, with 45.2% showing at least a one-stage improvement compared to 20.6% in the placebo group. • The Phase II trial also revealed that 67.7% of patients treated with efimosfermin alfa achieved MASH resolution without fibrosis worsening, versus 29.4% in the placebo group, indicating a significant treatment effect. • Efimosfermin alfa, a long-acting FGF21 analog administered monthly, offers a potentially more convenient dosing schedule compared to other FGF21 analogs in development for MASH. • The drug exhibited a good tolerability profile over 24 weeks, with a low incidence of injection-site reactions and gastrointestinal toxicities, supporting its further development.

• Efimosfermin alfa demonstrated statistically significant improvement in liver fibrosis without worsening of MASH compared to placebo over 24 weeks. • Two-thirds of patients treated with efimosfermin achieved MASH resolution without worsening of fibrosis, showing a significant benefit over placebo. • The study also revealed significant and rapid improvements in cardiometabolic parameters, including liver fat reduction and glycemic control. • Boston Pharmaceuticals plans to advance efimosfermin to late-stage clinical development in 2025 based on these promising Phase 2 results.

GSK has agreed to acquire Boston Pharmaceuticals' phase 3-ready liver disease candidate efimosfermin alfa for $1.2 billion upfront, with potential milestone payments bringing the total to $2 billion.