A Double-blind, Randomized, Placebo-controlled, Repeat Dose, 2-way Crossover Drug Interaction Study to Investigate the Pharmacokinetic and Pharmacodynamic Effects Following Administration of Fluticasone Furoate/GW642444M Inhalation Powder With Ketoconazole

A randomized two-way crossover study to determine whether concomitant administration of CYP P450 3A4 inhibitor ketoconazole and fluticasone furoate/GW642444M combination significantly increases the systemic effects and exposure to repeat dose fluticasone furoate and/or GW642444 in healthy subjects. Key assessments will include blood potassium, heart rate, blood pressure, QTc, serum cortisol and pharmacokinetic parameters, and safety including vital signs, ECGs, adverse event monitoring and laboratory safety tests, including blood glucose.