Role of Resmetirom, a Liver-Directed, Thyroid Hormone Receptor Beta-Selective Agonist, in Managing Nonalcoholic Steatohepatitis: A Systematic Review and Meta-Analysis.

Background: Resmetirom, a liver-directed, thyroid hormone receptor beta-selective agonist, has recently been approved to treat nonalcoholic steatohepatitis (NASH). This meta-analysis aimed to summarize the efficiency and safety of resmetirom in treating NASH.

Methods: Electronic databases were searched for randomized controlled trials (RCTs) of resmetirom vs placebo in patients with NASH. The primary outcomes were the changes from baseline in hepatic fat content, liver histology, including NASH resolution, and noninvasive markers of hepatic fibrosis.

Results: Three randomized controlled trials (n = 2231) met the inclusion criteria. Compared to placebo, resmetirom achieved greater reductions from baseline in hepatic fat content assessed by magnetic resonance imaging proton density fat fraction (for resmetirom 80 mg: MD -27.76% [95%CI: -32.84, -22.69]; for resmetirom 100 mg: MD -36.01% [95%CI: -41.54, -30.48]; P < .00001 for both) and FibroScan controlled attenuation parameter (for resmetirom 80 mg: MD -21.45 dBm [95%CI: -29.37, -13.52]; for resmetirom 100 mg: MD -25.51 dBm [95%CI: -33.53, -17.49]; P < .00001 for both). Resmetirom 80 mg outperformed placebo in NASH resolution and ≥2-point nonalcoholic fatty liver disease activity score reduction. Moreover, resmetirom 80 mg and 100 mg were superior to placebo in cytokeratin-18 (M30) reduction. Greater reductions in liver enzymes, lipids, and reverse triiodothyronine were observed in the resmetirom arms with no impact on triiodothyronine. Nausea and diarrhea were more common with resmetirom than with placebo; other adverse events were comparable.

Conclusion: Resmetirom improves hepatic fat content, liver enzymes, and fibrosis biomarkers in NASH patients. Resmetirom generally does not affect thyroid function and is well-tolerated.