Icotrokinra (JNJ-77242113) acetate is a potent oral selective antagonist of the IL-23 receptor. It inhibits IL-23-induced STAT3 phosphorylation in peripheral blood mononuclear cells (PBMC) with an IC50 of 5.6 pM and reduces IFN-γ production in natural killer (NK) cells induced by IL-23, with an IC50 of 18.4 pM. Icotrokinra acetate demonstrates anti-inflammatory properties in a TNBS-induced rat colitis model and is applicable to research on psoriasis, psoriatic arthritis, and inflammatory bowel diseases.