C5a Receptor Antagonist, W-54011 is a potent, specific, and orally active CD88 (C5a receptor) antagonist. Shown to inhibit the binding of 125I-rhC5a to human neutrophils with a Ki of 2.2 nM, as well as C5a-induced intracellular Ca2+-mobilization, chemotaxis and reactive oxygen species (ROS) generation (IC50 = 3.1 nM, 2.7 nM and 1.6 nM, respectively) with no agonist activity up to 10 μM. Shown to prevent C5a-induced neutrophenia in gerbils (100 μg/kg i.v. or 3-30 mg/kg orally).
