Role of Obeticholic Acid, a Farnesoid X Receptor Agonist, in Nonalcoholic Fatty Liver Disease: A Systematic Review and Meta-analysis.

Background. Obeticholic acid (OCA) has emerged as a promising drug in the management of nonalcoholic fatty liver disease (NAFLD). This meta-analysis aimed to analyse the therapeutic effect of OCA on NAFLD. Methods. Randomized controlled trials (RCTs) involving patients with NAFLD receiving OCA in the intervention arm and placebo in the control arm were searched throughout the electronic databases. The primary outcomes were changes in non-invasive markers of hepatic fibrosis and liver histology. The secondary outcomes included changes in liver enzymes, metabolic parameters from baseline and adverse events (AEs). Results. Four RCTs involving 1,278 subjects met the inclusion criteria. Over 6 weeks to 18 months of clinical use, OCA outperformed placebo in resolving definite nonalcoholic steatohepatitis (odds ratio [OR] 1.60, 95% confidence interval [CI] [1.04-2.48], p=0.03) and improving fibrosis (OR 2.23, 95% CI [1.56-3.20], p<0.0001), hepatocellular ballooning (OR 1.83, 95% CI [1.35-2.47], p<0.0001) and lobular inflammation (OR 1.62, 95% CI [1.13-2.32], p=0.009). OCA did not improve the enhanced liver fibrosis score and steatosis better than placebo, and demonstrated superior efficacy compared with the placebo in reducing serum alanine aminotransferase, aspartate aminotransferase and gamma-glutamyl transferase levels. Although a favourable effect of OCA over placebo was seen in body-weight reduction, the OCA use was associated with adverse changes in lipid parameters. Except for the greater risk of pruritus and constipation, the AE profile was comparable between the OCA and placebo groups. Conclusions. OCA has a favourable efficacy in improving liver histology and liver enzymes. However, the worsening of lipid parameters and other AEs with the OCA use warrants further investigation.