SCH 546738 is an effective and non-competitive CXCR3 antagonist. SCH 546738 bindings to the human CXCR3 receptor is determined (Ki: 0.4 nM) in multiple experiments.

CXCR3 (human):0.4 nM （ki）

SCH 546738 effectively and specifically inhibits CXCR3-mediated chemotaxis in human activated T cells (IC90: 10 nM). SCH 546738 displaces radiolabeled CXCL10 and CXCL11 from human CXCR3 (IC50: ranging from 0.8 to 2.2 nM) in a non-competitive manner. Competition of human CXCL10 and CXCL11 binding to human CXCR3 by SCH 546738 is determined at various concentrations of [125I]hCXCL10 and [125I]hCXCL11 around the Kd (50-100 pM) for the receptor [1].

SCH 546738 is a selective and effective CXCR3 antagonist with a good PK for in vivo studies. SCH 546738 has a favorable pharmacokinetic profile in rodents, the plasma concentrations of SCH 546738 in Lewis rat, and C57BL/6 mouse over 24 hr post-dose. SCH 546738 has strong cross-species activities with IC50 of 1.3 nM, 6.4 nM, 5.9 nM, and 4.2 nM in inhibiting the binding of [125I]hCXCL10 to CXCR3 of monkey, dog, mouse and rat origin, respectively [1].