7005 Characterization of Clinical Candidate Miricorilant in Preclinical Models for NASH

Abstract Disclosure: T.J. Moll: None. E.M. Viho: None. M. Gentenaar: None. H. Hunt: Employee; Self; Corcept Therapeutics. O.C. Meijer: Grant Recipient; Self; Corcept Therapeutics. J. Kroon: Research Investigator; Self; Corcept Therapeutics. Background and aim: Miricorilant (CORT118335) is a selective glucocorticoid receptor (GR) modulator that is under clinical development for the treatment of non-alcohol steatohepatitis (NASH). It was previously shown that miricorilant treatment effectively lowers hepatic lipid content in mouse models of NASH. The aim of this study is to further characterize the effects of miricorilant in the mouse liver and in human liver tissue. Methods: In mouse liver tissue, we investigated the agonistic and antagonistic properties of miricorilant on GR activity. Eight-week-old male C57BL/6J mice were fed with a control diet or miricorilant-supplemented diet (resulting in an estimated dose of 60 mg/kg/day) for 6 days and 1.5 mg/kg corticosterone was injected to monitor the effects of miricorilant on GR-responsive gene expression. We next accessed the time-dependency of the lipid-lowering effects of miricorilant in the mouse liver. Mice were fed with a high-fat, high-fructose diet (HFHFD) for 3 weeks before treatment with 60 mg/kg/day miricorilant for one, three or six days by oral gavage, and triglyceride content in the liver was measured at endpoint. In human liver tissue, we investigated the effects of miricorilant on precision-cut liver slices (PCLS) obtained from two independent donors with pre-existing steatosis. PCLS were cultured for a total of 168 hours in the presence of 100 nM hydrocortisone, and with or without an exogenous lipid challenge. PCLS were treated with 200-600 nM miricorilant for 96 hours before triglyceride content was measured. RNA-sequencing was performed on PCLS after 24 hours of 200-400 nM miricorilant exposure. Results: In the mouse liver, miricorilant exhibited a unique combination of agonistic and antagonistic properties on GR-responsive gene expression. Miricorilant effectively lowered HFHFD-induced lipid accumulation in the mouse liver as soon as three days after treatment. In human PCLS, miricorilant treatment lowered triglyceride content in both donors. RNA-sequencing revealed respectively 40 and 128 differentially expressed genes after 200 and 400 nM miricorilant treatment. Pathway analysis revealed very-low-density lipoprotein (VLDL) particle remodeling as a significant enriched pathway, providing a possible explanation for the lowered triglyceride content upon miricorilant treatment. Conclusion: Miricorilant rapidly and effectively lowers hepatic lipid content in the mouse liver and in human PCLS, possibly via modulation of VLDL remodeling. Presentation: 6/2/2024