A Study to Compare the Efficacy and Safety of Fluticasone Furoate (FF) 100 mcg Once Daily With Fluticasone Propionate (FP) 250 mcg Twice Daily (BD) and FP 100 mcg BD in Well-controlled Asthmatic Japanese Subjects

The primary aim of this study is to clarify the position of FF and FF/Vilanterol (VI) 100/25 micrograms (mcg) compared with existing therapies by assessing FF dosage equivalent to low to middle-dose inhaled corticosteroids (ICS). The study is divided into Run-in period, Period 1 (open-label treatment), Period 2 (double blind treatment) and Follow-up. Subjects with well controlled asthma after completing a run-in period of 4 weeks will be switched from middle-dose ICS/long acting beta 2 agonist (LABA) equivalent dose to once-daily FF/VI 100/25 mcg for an 8 weeks treatment period (Period 1). After this, subjects will be randomized in a 1:1:1 ratio to receive either FP 250 mcg twice daily, FP 100 mcg twice daily or FF 100 mcg once daily in a 12 week double blind treatment period (Period 2). There will be a 1 week Follow-up Period following completion of the double-blind treatment period, or early withdrawal from the study. Overall , the total duration of subject's participation in the study will be for 25 weeks. RELVAR is a registered trademark of the GSK group of companies.