A randomised, placebo controlled thorough QTc study to evaluate the effect of repeat dose FF/GW642444M combination, with moxifloxacin as a positive control, on the QTc interval in healthy male and female subjects. Key assessments will include 12- lead electrocardiogram (ECG) and pharmacokinetic (PK) parameters, along with safety being assessed by blood pressure, heart rate, clinical laboratory safety tests, and collection of adverse events.