Pharmacokinetics, mass balance and metabolic profiling of resmetirom in healthy subjects and nonclinical metabolism and disposition

reached within 3-4 h. Radioactivity was largely confined to plasma vs whole blood, with parent compound the predominant radiolabelled species and MGL-3623 the major metabolite. Total recovery was 91.0% (excretion: 67.4% faecal, 23.6% urinary); in excreta, resmetirom was a minor component and no single metabolite exceeded 10% of dose. Resmetirom inhibited CYP2C8 and weakly induced CYP2B6 and CYP3A4 in vitro.These findings demonstrate the consistent metabolic profile and favourable hepatic disposition of resmetirom across species, supporting its pharmacokinetic properties in humans for treatment of MASH.