In Vitro: S18-000003 inhibits human and mouse RORγt-dependent transactivation, with IC50s of 0.029 and 0.34 μM respectively in cell-based GAL4 promoter reporter assays. S18-000003 (0.003-0.3 μM; 7 d) dose-dependently inhibits Th17 cell differentiation from human naive CD4+T cells, with an IC50 of 0.024 μM. S18-000003 (0.1-3 μM; 4 d) inhibits the differentiation of mouse Th17 cells from splenic naive CD4+T cells, with an IC50 of 0.20 μM. S18-000003 (0.03-1 μM; 3 d) reduces the IL-17 production in human PBMCs in a dose-dependent manner, and does not inhibit either the production of other cytokines (IL-2, IL-4, IL-10 and IFN-g) or cell proliferation. S18-000003 (0.1-3 μM; 3 d) reduces IL-17 and IL-22 production in PBMCs from psoriatic mice in a dose-dependent manner.
In Vivo: S18-000003 (30-100 mg/kg; p.o.) inhibits IL-17 production in the skin of IL-23-treated mice in a dose-dependent manner. S18-000003 (0.1-8%; 100mL; topically administration once daily for 14 days) ameliorates psoriasis-like lesions in TPA-induced K14.Stat3C transgenic mice, and has little impact on the thymus. S18-000003 (0.5 mg/kg; i.v.) exhibits the half-life (3.2 h), AUC (1930 ng•h/mL), CLtot (4.33 mL/min/kg) and Vdss in rats. S18-000003 (1 mg/kg; p.o.) exhibits the oral bioavailability (54.5%), Cmax (185 ng/mL), AUC (2110 ng•h/mL) and Tmax (4 h) in rats.