This is a phase III, multicenter, randomized, double-blind active controlled 2-arm parallel group to compare superiority of CHF 1535 pMDI compared to CHF 718 pMDI in terms of change from baseline in FEV1 AUC0-12h at Week 12.~After screening, eligible subjects will enter a 2-week run-in period using CHF 718 (BDP) pMDI 100µg, followed by a 12-week double-blind, treatment period. Screened subjects who were on a medium dose ICS or medium dose ICS-LABA prior to the study will be put on CHF 718 pMDI 100µg 2 inhalations BID (TDD 400µg) during the 2-week run in period. Screened subjects who were on a high dose ICS prior to the study will be put on CHF 718 pMDI 100µg 4 inhalations BID (TDD 800µg) during the 2-week run in period.~Following the run-in period, eligible subjects will be randomized to one of two study drug arms (using a 1:1 allocation ratio) for 12 weeks. A total of 6 clinic visits (V0- V5) and a follow-up call (V6) will be performed during the study.~During the study, daily symptoms, rescue medication use and compliance with the study drug will be recorded via a subject electronic diary. Subject concomitant medications, and adverse events will be assessed and recorded throughout the study. At study visits, subjects will undergo vital signs, physical exam, 12-lead ECG, PEF, and spirometry measurements, including serial spirometry at V2 and V5. Symptoms will be assessed through disease specific questionnaires. Routine hematology, blood chemistry, and serum pregnancy testing will be performed before enrollment and at end of study.
The purpose of this study is to compare the superiority of CHF 1535 compared to CHF 718 in subjects with asthma on medium or high dose inhaled corticosteroids.