Patients' eligibility was checked during the screening visit including the review of medical history, spirometry assessments, routine labs, physical examination, 12-lead ECG, vital signs measurement. This visit was followed by a 2-week open-label run-in period under Foster® (BDP/FF 400/24 µg total daily dose). Eligible patients were then randomised to either fixed triple therapy BDP/FF/GB or BDP/FF. During the 52-week treatment period, completing patients did have 5 subsequent visits post randomisation scheduled respectively after 4 (Visit 3), 12 (Visit 4), 26 (Visit 5), 40 (Visit 6) and 52 (Visit 7) weeks of treatment.