Vicriviroc is a chemokine (C-C motif) receptor 5 (CCR5) antagonist (Ki = 2.5 nM). It selectively inhibits CCR5 over M1 and M2 muscarinic acetylcholine receptors (Kis = >10,000 nM for both) and human-ether-a-go-go (hERG) potassium channels (IC50 = 5.8 μM). Vicriviroc decreases chemotaxis induced by chemokine (C-C motif) ligand 3 (CCL3) in Ba/F3 cells expressing recombinant human CCR5 with an IC50 value of 0.91 nM. It inhibits the replication of 30 R5-tropic HIV-1 clinical isolates in peripheral blood mononuclear cells (PBMCs; EC50s = 0.04-1.4 nM) and reduces viral entry of seven drug-resistant strains of HIV-1 in U87 cells expressing CD4 and CCR5 (EC50s = 8.7-32.9 nM).
