Cilofexor, a Nonsteroidal FXR Agonist, in Patients With Noncirrhotic NASH: A Phase 2 Randomized Controlled Trial

Background and aims We evaluated the safety and efficacy of cilofexor (formerly GS-9674), a small-molecule nonsteroidal agonist of farnesoid X receptor, in patients with nonalcoholic steatohepatitis (NASH). Approach and results In this double-blind, placebo-controlled, phase 2 trial, 140 patients with noncirrhotic NASH, diagnosed by magnetic resonance imaging-proton density fat fraction (MRI-PDFF) ≥8% and liver stiffness ≥2.5 kPa by magnetic resonance elastography (MRE) or historical liver biopsy, were randomized to receive cilofexor 100 mg (n = 56), 30 mg (n = 56), or placebo (n = 28) orally once daily for 24 weeks. MRI-PDFF, liver stiffness by MRE and transient elastography, and serum markers of fibrosis were measured at baseline and week 24. At baseline, median MRI-PDFF was 16.3% and MRE-stiffness was 3.27 kPa. At week 24, patients receiving cilofexor 100 mg had a median relative decrease in MRI-PDFF of -22.7%, compared with an increase of 1.9% in those receiving placebo (P = 0.003); the 30-mg group had a relative decrease of -1.8% (P = 0.17 vs. placebo). Declines in MRI-PDFF of ≥30% were experienced by 39% of patients receiving cilofexor 100 mg (P = 0.011 vs. placebo), 14% of those receiving cilofexor 30 mg (P = 0.87 vs. placebo), and 13% of those receiving placebo. Serum gamma-glutamyltransferase, C4, and primary bile acids decreased significantly at week 24 in both cilofexor treatment groups, whereas significant changes in Enhanced Liver Fibrosis scores and liver stiffness were not observed. Cilofexor was generally well-tolerated. Moderate to severe pruritus was more common in patients receiving cilofexor 100 mg (14%) than in those receiving cilofexor 30 mg (4%) and placebo (4%). Conclusions Cilofexor for 24 weeks was well-tolerated and provided significant reductions in hepatic steatosis, liver biochemistry, and serum bile acids in patients with NASH. ClinicalTrials.gov No. NCT02854605.