This is a phase III, 4-week, randomized, double-blind, parallel group, multicenter study comparing FF/UMEC/VI (100 micrograms [mcg]/62.5 mcg/25 mcg) delivered via a single ELLIPTA® inhaler ('closed' triple) + matching placebo ELLIPTA inhaler, FF/VI + UMEC delivered via two ELLIPTA inhalers ('open' triple) and FF/VI via a single ELLIPTA inhaler + matching placebo ELLIPTA inhaler, all once daily. The total duration of subject participation will be approximately 7 weeks, consisting of a 2-week run-in period, 4-week treatment period and a 1-week follow-up period.