Zalfermin Plus Semaglutide Fails to Add Fibrosis Benefit in MASH: The Lancet | September 2026

Introduction:

Patients with MASH and advanced fibrosis remain at substantial risk of cirrhosis and liver-related complications. Because MASH involves multiple metabolic and fibrogenic pathways, combination therapy is attractive. This Phase II trial evaluated whether the FGF21 analogue zalfermin plus semaglutide 2.4 mg could improve liver fibrosis beyond either therapy alone in patients with F2–F4 compensated disease.

Why was this study needed?

Effective therapies remain limited for advanced MASH, particularly compensated cirrhosis (F4c).

FGF21 and GLP-1 receptor agonists target complementary metabolic pathways.

Preclinical studies suggested potential synergy between zalfermin and semaglutide.

This was the first randomized trial evaluating this combination in F2–F4c MASH.

Results:

In 698 patients, zalfermin plus semaglutide did not significantly improve fibrosis without worsening MASH compared with placebo and showed no additive benefit over monotherapy.

Semaglutide 2.4 mg alone showed a promising fibrosis benefit, including an encouraging signal in patients with compensated cirrhosis (F4c).

The most frequent adverse effects were gastrointestinal, particularly with combination therapy, and were predominantly mild to moderate.

Overall, the trial failed to confirm the anticipated synergy between FGF21 and GLP-1 receptor agonism.

Clinical Impact:

This study challenges the assumption that combining two promising metabolic therapies will necessarily improve MASH outcomes. Adding zalfermin did not enhance the histological benefit of semaglutide. More importantly, the encouraging signal with semaglutide in compensated MASH cirrhosis deserves dedicated investigation, as this remains an important unmet therapeutic area.

Bottom Line:

Zalfermin plus semaglutide did not provide additional fibrosis benefit in F2–F4 compensated MASH. Semaglutide alone showed a promising antifibrotic signal, including in compensated cirrhosis, supporting further evaluation in F4 disease.