A STUDY TO EVALUATE THE 24 HOUR SPIROMETRIC EFFECT (FEV1) OF FLUTICASONE FUROATE/VILANTEROL INHALATION POWDER (100MCG FLUTICASONE FUROATE (FF)/25MCG VILANTEROL (VI)) COMPARED WITH SALMETEROL/FLUTICASONE PROPIONATE INHALATION POWDER (50MCG SALMETEROL/500MCG FLUTICASONE PROPIONATE (FP)):