Effect of pharmacological interventions and placebo on liver Histology in nonalcoholic steatohepatitis: A network meta-analysis

Background: The aims of this study were to quantify the histological improvement and its risk factors in patients with NASH enrolled in the placebo arms of randomized controlled trials (RCTs), and to indirectly compare the effect of several investigational drugs for NASH on validated histological outcomes.Data synthesis: A comprehensive search was conducted to detect phase 2 and 3 RCTs comparing pharmacological interventions in patients with NASH. According to Food and Drug Administra-tion (FDA) recommendations, primary outcomes included: 1) NASH resolution without wors-ening of fibrosis; 2) At least 1-point reduction in fibrosis without worsening of NASH. Meta -analysis and meta-regressions were conducted on placebo arms, while network meta-analysis was performed on intervention arms.A total of 15 RCTs met the eligibility criteria. The meta-analysis on placebo arms showed a pooled estimate rate of 17% (95%C.I. 12%-23%;I2 = 86%; p < 0.01) for NASH resolution without worsening of fibrosis and of 21% (95%C.I. 13%-31%;I2 = 84%; p < 0.01) for >= 1stage improvement of fibrosis without worsening of NASH. Phase 3 (vs Phase 2)RCTs, older age and higher AST levels were significantly associated with progression of liver disease by univariate meta-regression. At network meta-analysis, Semaglutide (P-score 0.906), Pioglitazione alone (score 0.890) and plus Vitamin E (0.826) had the highest probability of being ranked the most effective intervention for NASH resolution without worsening of fibrosis, while Aldafermin (0.776), Lanifibranor (0.773) and Obeticholic acid (0.771) had the highest probability to achieve >= 1 stage of fibrosis improvement without worsening of NASH.

Automated summary

This study aimed to quantify histological improvement and its risk factors in NASH patients enrolled in the placebo arms of RCTs, and to compare the effect of investigational drugs for NASH on histological outcomes. The meta-analysis on placebo arms showed NASH resolution without worsening of fibrosis in 17% of patients and at least 1 stage improvement of fibrosis without worsening of NASH in 21% of patients. Phase 3 RCTs, older age, and higher AST levels were associated with progression of liver disease. Network meta-analysis suggested that Semaglutide, Pioglitazone alone or in combination with Vitamin E, Aldafermin, Lanifibranor, and Obeticholic acid were the most effective interventions for NASH improvement and fibrosis reduction.