Study in Adult Patients With Moderate to Severe Asthma

This was a phase IIIb, exploratory, double-blind, randomised, multicentre, psychopharmacological, 2x2 cross-over study in adult subjects with moderate to severe asthma. A total of 78 randomised subjects in 10 actives centres were involved. The study focused on the psychopharmacological aspects, particularly on the subjects' preference for the device and on the impact of the device's features on subjects' perception of asthma symptoms. Subjects were informed that the study treatments were the same medication they had received before enrolment as maintenance therapy (i.e. Foster® 100/6 µg pMDI), but with differing device characteristics. The study lasted approximately 6 weeks for each subject and comprised four visits (Visit \[V\] 1 to V4), including: * Two face-to-face clinic visits: V1 (Day 1, screening/randomisation visit) and V4 (Day 43); * Two remote video contact visits: V2 (Day 15) and V3 (Day 29). After signing the ICF, subjects were screened at the investigational site during the screening/randomisation visit (V1). On the same day, and after checking all inclusion and exclusion criteria, eligible subjects were randomised to one of two study treatment sequences and followed the study treatment sequence as follows: * From V1 (Day 1), subjects were treated with commercial Foster® 100/6 µg pMDI during the 14-day baseline period; * From V2 (Day 15), subjects were instructed to take CHF1535 100/6 µg pMDI via Inhaler A and Inhaler B during two consecutive periods of 14 days each (first and second treatment periods) in a sequential way dictated by the randomisation: * Either CHF1535 100/6 µg pMDI with Inhaler A then CHF1535 100/6 µg pMDI with Inhaler B; or * CHF1535 100/6 µg pMDI with Inhaler B then CHF1535 100/6 µg pMDI with Inhaler A. The first treatment period started at V2 (Day 15) and the second treatment period started at V3 (Day 29), with the end of study visit taking place at V4 (Day 43). A window of ±1 day was allowed for the dates of all study visits except V1 (Day 1). Please note that "Change from baseline in average VAS score perceptions of asthma-over the 14 Days of treatment - Question #3" was reported as PRIMARY ENDPOINT to comply with CT.gov register requirements, but it should be considered as an OTHER PRE-SPECIFIED endpoint like the other endpoint listed.