A phase 3 clinical trial evaluated resmetirom, a thyroid hormone receptor beta agonist, in patients with nonalcoholic steatohepatitis (NASH) and liver fibrosis. The study involved 966 adults with biopsy-confirmed NASH and fibrosis stages F1B, F2, or F3. Participants were randomly assigned to receive resmetirom at 80 mg or 100 mg daily, or placebo. At week 52, 25.9% of resmetirom 80-mg recipients and 29.9% of resmetirom 100-mg recipients achieved NASH resolution without worsening fibrosis, compared to 9.7% in the placebo group. Similarly, 24.2% and 25.9% of resmetirom groups showed fibrosis improvement by one stage without worsening NASH activity score, versus 14.2% in the placebo group. LDL cholesterol levels decreased by 13.6% and 16.3% in resmetirom groups, compared to 0.1% in the placebo group. Adverse events, including diarrhea and nausea, were more common in resmetirom groups. Serious adverse events occurred in similar rates across groups. Resmetirom showed significant improvements in NASH resolution and fibrosis, with no major safety concerns. The study supports resmetirom as a potential treatment for NASH with liver fibrosis. The trial was funded by Madrigal Pharmaceuticals.A phase 3 clinical trial evaluated resmetirom, a thyroid hormone receptor beta agonist, in patients with nonalcoholic steatohepatitis (NASH) and liver fibrosis. The study involved 966 adults with biopsy-confirmed NASH and fibrosis stages F1B, F2, or F3. Participants were randomly assigned to receive resmetirom at 80 mg or 100 mg daily, or placebo. At week 52, 25.9% of resmetirom 80-mg recipients and 29.9% of resmetirom 100-mg recipients achieved NASH resolution without worsening fibrosis, compared to 9.7% in the placebo group. Similarly, 24.2% and 25.9% of resmetirom groups showed fibrosis improvement by one stage without worsening NASH activity score, versus 14.2% in the placebo group. LDL cholesterol levels decreased by 13.6% and 16.3% in resmetirom groups, compared to 0.1% in the placebo group. Adverse events, including diarrhea and nausea, were more common in resmetirom groups. Serious adverse events occurred in similar rates across groups. Resmetirom showed significant improvements in NASH resolution and fibrosis, with no major safety concerns. The study supports resmetirom as a potential treatment for NASH with liver fibrosis. The trial was funded by Madrigal Pharmaceuticals.