Dataset from An Escalating Dose, Randomized, Placebo-controlled, Incomplete-block, 2-period Cross-over Study to Assess the Dose Response for Topical Efficacy Via Airway Responsiveness to Adenosine-5'-Monophosphate (AMP) Challenge and the Dose Response for Systemic Activity Via 24h Plasma Cortisol Suppression and Thereby the Relative Therapeutic Index for Fluticasone Furoate (FF), Fluticasone Propionate (FP) and Budesonide (BUD) in Asthmatic Subjects

This is a randomized, placebo-controlled, 2-period crossover, escalating repeat dose study, aiming to investigate whether higher potency of different inhaled corticosteroid confers an improvement in the topical efficacy to systemic activity ratio in asthmatic subjects. It will compare the dose response for topical efficacy via airway responsiveness (to adenosine-5'-monophosphate [AMP] challenge), and the dose response for systemic activity via 24 hour plasma cortisol suppression, and thereby compare the relative therapeutic index, for the following inhaled corticosteroids: fluticasone furoate (FF), fluticasone propionate (FP) and budesonide (BUD). There will be a screening visit 4 - 42 days before the first dose of study treatment, and AMP challenge Provocative concentration 20 (PC20) of <=80 milligrams per milliliter (mg/mL) at screening visit 2 i.e. at 4 - 14 days before the first dose of study treatment. Subjects will be randomized to one of 5 or 12 treatment sequences, and will have one or two treatment periods, each comprising 5 consecutive 7-day phases of escalating doses of either FF, FP, BUD or placebo. There will be a 25- to 42-day washout period between treatment periods. The study duration for each subject will be approximately 13 or 24 weeks including the follow-up period.