Clinical trial: Effects of pegozafermin on the liver and on metabolic comorbidities in subjects with biopsy‐confirmed nonalcoholic steatohepatitis

Summary Background An approved therapy for nonalcoholic steatohepatitis (NASH) and fibrosis remains a major unmet medical need. Aim To investigate the histological and metabolic benefits of pegozafermin, a glycoPEGylated FGF21 analogue, in subjects with biopsy‐confirmed NASH. Methods This proof‐of‐concept, open‐label, single‐cohort study, part 2 of a phase 1b/2a clinical trial, was conducted at 16 centres in the United States. Adults (age 21–75 years) with NASH (stage 2 or 3 fibrosis, NAS≥4) and magnetic resonance imaging proton density fat fraction (MRI‐PDFF) ≥8% received subcutaneous pegozafermin 27 mg once weekly for 20 weeks. Primary outcomes were improvements in liver histology, and safety and tolerability. Results Of 20 enrolled subjects, 19 completed the study. Twelve subjects (63%) met the primary endpoint of ≥2‐point improvement in NAFLD activity score with ≥1‐point improvement in ballooning or lobular inflammation and no worsening of fibrosis. Improvement of fibrosis without worsening of NASH was observed in 26% of subjects, and NASH resolution without worsening of fibrosis in 32%. Least‐squares mean relative change from baseline in MRI‐PDFF was −64.7% (95% CI: −71.7, −57.7; p < 0.0001). Significant improvements from baseline were also seen in serum aminotransferases, noninvasive fibrosis tests, serum lipids, glycaemic control and body weight. Adverse events (AEs) were reported in 18 subjects (90%). The most frequently reported AEs were mild/moderate nausea and diarrhoea. There were no serious AEs, discontinuations due to AEs, or deaths. Conclusions Pegozafermin treatment for 20 weeks had beneficial effects on hepatic and metabolic parameters and was well tolerated in subjects with NASH. ClinicalTrials.gov : NCT04048135.