Efruxifermin (EFX)
Our investigational drug, efruxifermin (EFX), is designed to treat MASH.
EFX has been engineered to mimic the biological activity of fibroblast growth factor 21 (FGF21), which regulates multiple metabolic pathways and cellular processes. By delivering sustained and balanced signaling through FGF21’s receptors in liver and adipose tissue, EFX has the potential to treat MASH by addressing all core drivers of disease progression.
EFX leverages the whole body to improve metabolic balance.
EFX is being evaluated in the Phase 3 SYNCHRONY program, which is composed of three clinical trials designed to support regulatory approval of EFX for the treatment of MASH.
The SYNCHRONY program builds on results from two 96-week Phase 2b clinical trials.
HARMONY Study
The first Phase 2b study evaluated the efficacy and safety of EFX in people with noncirrhotic MASH and moderate to advanced fibrosis (F2/F3).
Fibrosis improvements were observed with EFX compared with placebo at Week 24,1 with larger improvements at Week 96 (end of study).2 In addition, EFX improved MASH histology, reduced liver fat, and improved noninvasive tests of fibrosis and cardiometabolic markers. Following topline data from HARMONY released in September 2022, EFX received Breakthrough Therapy Designation from the FDA for the treatment of MASH.
SYMMETRY Study
The second Phase 2b study evaluated the efficacy and safety of EFX in people with MASH and compensated cirrhosis (F4c).3 EFX improved fibrosis compared with placebo at Week 96 and improved noninvasive measures of fibrosis, liver injury, insulin sensitivity, and lipids. These results support the potential of EFX to reverse fibrosis in people with a high risk of developing liver-related complications.
EFX was generally well tolerated with an acceptable safety profile.1–6 The most common side effects (or adverse events) were mild or moderate gastrointestinal events as well as injection site reactions.
References
- Harrison S, Frias J, Neff G, et al. Safety and efficacy of once-weekly efruxifermin versus placebo in non-alcoholic steatohepatitis (HARMONY): a multicentre, randomised, double-blind, placebo-controlled, phase 2b trial. The Lancet Gastroenterology & Hepatology. 2023;8(12):1080-1093.
- Noureddin M, Frias J, Neff G, et al. Safety and efficacy of once-weekly efruxifermin versus placebo in metabolic dysfunction-associated steatohepatitis (HARMONY): 96-week results from a multicentre, randomised, double-blind, placebo-controlled, phase 2b trial. The Lancet. 2025;406(10504):719-730.
- Noureddin M, Rinella M, Chalasani N, et al. Efruxifermin in compensated liver cirrhosis caused by MASH. N Engl J Med. 393,1038-1039.
- Harrison SA, Ruane PJ, Freilich BL, et al. Efruxifermin in non-alcoholic steatohepatitis: a randomized, double-blind, placebo-controlled, phase 2a trial. Nat Med. 2021;27(7):1262–1271.
- Harrison S, Ruane P, Freilich B, et al. A randomized, double-blind, placebo-controlled phase IIa trial of efruxifermin for patients with compensated NASH cirrhosis. JHEP Reports. 2022; 5(1):100563.
- Harrison S, Frias J, Lucas K, et al. Safety and efficacy of efruxifermin in combination with a GLP-1 receptor agonist in patients with NASH/MASH and type 2 diabetes in a randomized phase 2 study. Clin Gastroenterol Hepatol. 2024;23:103-113.
