Efimosfermin alfa

GSK has announced that it will be acquiring Boston Pharmaceuticals’ phase 3-ready liver disease candidate in a deal worth up to $2bn. Efimosfermin alfa is an investigational drug in clinical development to treat and prevent the progression of steatotic liver disease (SLD), a condition characterised by the buildup of fat in the liver and associated with inflammation and fibrosis. SLD, including metabolic dysfunction-associated steatohepatitis (MASH) and alcohol-related liver disease (ALD), affects approximately 5% of the global population and represents an area of significant unmet medical need, according to GSK. Given as a once-monthly subcutaneous injection, efimosfermin is fibroblast growth factor 21 (FGF21) analog therapeutic that has already been shown in a phase 2 trial to “rapidly and significantly” reverse liver fibrosis and stop its progression in patients with moderate-to-advanced MASH. The drug will also be evaluated in ALD and, “given its direct anti-fibrotic mechanism of action”, GSK said the asset could address more advanced stages of SLD and be used in combination with its siRNA therapeutic GSK’990, which is currently in development for other subsets of SLD patients. GSK’s chief scientific officer, Tony Wood, said efimosfermin “has the potential to define a new standard-of-care with its monthly dosing and tolerability profile”. He continued: “Efimosfermin will significantly expand our hepatology pipeline and provide us the opportunity to develop a new potential best-in-class medicine with first launch expected in 2029. It complements GSK‘990, also in development for ALD and MASH, offering GSK options to develop both monotherapy and potential combinations to improve patient outcomes.” GSK will gain access to efimosfermin by acquiring Boston’s subsidiary BP Asset IX for $1.2bn upfront and up to $800m in success-based milestone payments. The drugmaker will also be responsible for success-based milestone payments as well as tiered royalties for efimosfermin owed to Novartis Pharma. Elias Zerhouni, chair of the Boston’s board, said: “We are delighted that GSK… recognised efimosfermin’s potential to address a growing global public health concern and unmet medical need. Together, we look forward to efimosfermin’s ongoing journey to become a best-in-class treatment for patients with SLD.”