PMX 53 monoacetate (3D53 monoacetate) is a potent orally active CD88 (C5aR) antagonist that inhibits C5a-induced neutrophil myeloperoxide release and chemotactic activity. PMX 53 monoacetate has an IC50 value of 20 nM against C5a-induced neutrophil myeloperoxide release. >The value is 22 nM, and the IC50 value of the chemotactic activity is 75 nM. PMX 53 monoacetate is also an agonist of MrgX2[1].