SCH 563705 is a potent and orally available CXCR2 and CXCR1 antagonist, with IC50s of 1.3 nM, 7.3 nM and Kis of 1 and 3 nM, respectively. SCH 563705 (Compound 16) is a potent and orally available CXCR2 and CXCR1 antagonist, with IC50s of 1.3 nM, 7.3 nM and Kis of 1 and 3 nM, respectively. SCH 563705 shows potent inhibition against both Gro-a and IL-8 induced human neutrophil migration (chemotaxis IC50 = 0.5 nM, against 30 nM of Gro-a; chemotaxis IC50 = 37 nM, against 3 nM of IL-8). SCH 563705 potently inhibits mouse CXCR2 (IC50 = 5.2 nM). SCH 563705 has good oral pharmacokinetic profiles in rats, mice, monkeys and dogs. SCH 563705 (50 mg/kg p.o) reduces blood Ly6G+ Ly6C+ neutrophil frequency and unchanged levels of Ly6GLy6Chi monocytes. SCH563705 (3-30 mg/kg p.o) treatment causes a dosedependent elevation in plasma levels of CXCL1.