Study Evaluating the 24-Hour Pulmonary Function Profile of Fluticasone Furoate (FF) /GW642444 (Vilanterol) (VI) Inhalation Powder 100/25mcg Once Daily Compared With Fluticasone Propionate/Salmeterol Inhalation Powder 250/50mcg Twice Daily in Subjects With Chronic Obstructive Pulmonary Disease (COPD)

GSK Investigational Site, Witbank

GSK Investigational Site, Reiger Park

GSK Investigational Site, Benoni

GSK Investigational Site, Port Elizabeth

GSK Investigational Site, George

GSK Investigational Site, Somerset West

GSK Investigational Site, Bellville

GSK Investigational Site, Cape Town

GSK Investigational Site, Bloemfontein

GSK Investigational Site, Córdoba

GSK Investigational Site, Cherkassy

GSK Investigational Site, Rozzano (MI)

GSK Investigational Site, Vinnytsia

GSK Investigational Site, Lübeck

GSK Investigational Site, Ponferrada (León)

GSK Investigational Site, Lugo

GSK Investigational Site, Orangeburg

GSK Investigational Site, Spartanburg

GSK Investigational Site, Gaffney

GSK Investigational Site, Seneca

GSK Investigational Site, DeLand

GSK Investigational Site, Padua

GSK Investigational Site, Jasper

GSK Investigational Site, Parma

GSK Investigational Site, Cincinnati

GSK Investigational Site, Valladolid

GSK Investigational Site, Florence

GSK Investigational Site, Mykolayiv

GSK Investigational Site, Minneapolis

GSK Investigational Site, Torrette (AN)

GSK Investigational Site, Kharkiv

GSK Investigational Site, Kharkiv

GSK Investigational Site, Oklahoma City

GSK Investigational Site, Boerne

GSK Investigational Site, Napoli

GSK Investigational Site, San Felice A Cancello Caserta

GSK Investigational Site, Telese Terme (BN)

GSK Investigational Site, Donetsk

GSK Investigational Site, Coeur d'Alene

GSK Investigational Site, Palermo

GSK Investigational Site, Riverside

GSK Investigational Site, Medford

GSK Investigational Site, Rome

GSK Investigational Site, Cagliari

GSK Investigational Site, Thabazimbi

GSK Investigational Site, Alicante

GSK Investigational Site, Mérida (Badajoz)

GSK Investigational Site, Kiev

GSK Investigational Site, Kyiv

GSK Investigational Site, Kyiv

GSK Investigational Site, Kyiv