GSK buys Boston's developmental liver disease drug for up to $2bn

(Sharecast News) - GSK announced on Wednesday that it has entered into an agreement with Boston Pharmaceuticals to acquire its lead asset Efimosfermin for up to $2bn, buying a specialty medicine to treat and prevent progression of steatotic liver disease (SLD). Under the terms of the deal, GSK pay Boston $1.2bn upfront, with the potential for additional success-based milestone payments totalling $800m.

The acquisition will expand the British pharma giant's hepatology pipeline aimed at addressing steatotic and viral drivers of liver disease, offering multiple development options with the potential for first launch in 2029.

Efimosfermin is a once-monthly fibroblast growth factor 21 (FGF21) analog therapeutic ready for phase III development. Phase II data showed the potential for the drug to reverse liver fibrosis, demonstrated in metabolic dysfunction-associated steatohepatitis, otherwise known as MASH.

SLD, which affects up to 5% of the global population, represents an area of "significant unmet medical need" with limited treatment options, GSK said.

"Interventions that reduce moderate-to-advanced fibrosis to prevent progression of cirrhosis, liver cancer, hospitalisations and transplant could save the US healthcare system between $40-100bn over the next two decades," the company said.

"The FGF21 class has shown some of the most exciting data in MASH including first-in-disease evidence of cirrhosis reversal, and Efimosfermin has the potential to define a new standard-of-care with its monthly dosing and tolerability profile," said Tony Wood, GSK's chief scientific officer.