Metabolic dysfunction-associated steatotic liver disease (MASLD) has become the leading cause of liver disease worldwide, affecting approximately one in three people[9]. The inflammatory form of MASLD, called metabolic steatohepatitis (MASH), can progress to liver fibrosis and is the fastest growing cause of cirrhosis and hepatocellular carcinoma, especially in women[9]. Efimosfermin alfa is a new once-monthly drug that is a long-acting analog of fibroblast growth factor 21 (FGF21) with an extended half-life of 21 days[3]. In a 24-week phase 2b clinical trial, 68% of patients treated with efimosfermin achieved MASH resolution without worsening fibrosis compared to 29% in the placebo group[3]. Improvement of fibrosis by one grade without deterioration of MASH was achieved in 45% of patients treated with efimosfermin compared to 21% in the placebo group[3]. Efimosfermin was generally well tolerated, with the most common adverse effects being mild to moderate gastrointestinal symptoms such as nausea, diarrhea, and vomiting[1]. Ongoing phase 3 studies (ZENITH-1 and ZENITH-2) are further evaluating efimosfermin alfa in patients with confirmed F2/F3 fibrosis[2].