Approximately 24 subjects will be randomized to receive a single 500 mg dose of each of the five formulations of GSK1605786 after a standard breakfast. Serial pharmacokinetic samples will be collected following each dose and safety assessments will be performed. The relative bioavailability of the GSK capsule formulation will be compared to the ChemoCentryx formulation while the relative bioavailability the three other formulations will be compared to the GSK capsule formulation intended for use in a GlaxoSmithKline Phase IIb study.