Effect of Once-Daily Fluticasone Furoate/Vilanterol on 24-Hour Pulmonary Function in Patients With Chronic Obstructive Pulmonary Disease: A Randomized, Three-Way, Incomplete Block, Crossover Study

FF/VI inhaled once daily in the morning for 28 days produced significant improvements in pulmonary function with a prolonged (>24 hours') duration of action in this population of patients with COPD. The combination was well tolerated. ClinicalTrials.gov identifier: NCT01072149.