By Fineline Cube 
UK-based GlaxoSmithKline (GSK; NYSE: GSK) announced the completion of its acquisition of BP Asset IX, a subsidiary of US-based Boston Pharmaceuticals. The deal includes the investigational drug efimosfermin alfa, a potentially best-in-class, long-acting FGF21 analog currently in Phase III development for steatotic liver disease (SLD), including metabolic dysfunction-associated steatohepatitis (MASH) and alcohol-associated liver disease (ALD).
Drug Profile and Mechanism
Efimosfermin is designed as a once-monthly subcutaneous injectable FGF21 variant. It works by modulating key metabolic pathways to reduce liver fat, improve hepatic inflammation, and potentially reverse fibrosis in MASH patients. The drug is currently being evaluated in clinical trials for moderate-to-advanced fibrosis, including cirrhosis.
Market Potential and Combination Therapy
GSK believes efimosfermin could address significant unmet needs in advanced liver disease. The company is also exploring the potential combination use of efimosfermin with its siRNA therapy GSK’990, which targets other SLD patient subgroups.
Financial Details
The total cash consideration for the acquisition amounts to USD 2 billion. This includes an upfront payment of USD 1.2 billion and up to USD 800 million in success-based milestones. GSK will also assume responsibility for milestone payments and tiered royalties owed to Novartis. The company plans to commercially launch efimosfermin by 2029.-Fineline Info & Tech