A clinical trial, involving several sites in several countries, with a duration of 12 weeks, where patients, medical doctors and the sponsor do not know the treatment taken by the patient (between one study treatment and another one) with the scope of evaluating the safety of study treatment in comparison with another similar one in subjects with asthma.

INTERVENTION: This study will be composed of a 2‐week run‐in period with CHF5993 200/6/12.5 µg fixed combination of BDP 200 µg + FF 6 µg + GB 12.5 µg, via pMDI with HFA‐134a propellant (then refer as Reference product). This will be followed by a 12‐week treatment period with CHF5993 200/6/12.5 µg fixed combination of BDP 200 µg + FF 6 µg + GB 12.5 µg, via pMDI with HFA‐152a propellant (then refer as Test product) and Reference. Subjects will be centrally assigned through an IRT system to one of the two treatment arms in a 2:1 ratio for the Test product or Reference product An expected total duration of study participation (including pre‐screening/screening and follow‐up) is 16 weeks. In both treatment arms ( test and reference product ) the subject will be requested to take 2 inhalations twice daily (BID; i.e., 2 inhalations in the morning and 2 inhalations in the evening), with a total daily dose of BDP/FF/GB: 800/24/50 µg (subjects who inhale pMDI medications with a spacer should continue using the spacer AeroChamber Plus). The study involves a pre‐screening visit, a screening visit, and then a treatment phase with four on‐site visits, for up to 12 weeks. A follow‐up call will be done with subjects 7 to 10 days after a subject’s last intake of the study treatment to collect information on the subjects’ concomitant medications/procedures and adverse events (AEs). CONDITION: Asthma ; Respiratory PRIMARY OUTCOME: Potential for bronchoconstriction of each study treatment, defined as the relative change from pre‐dose in FEV1 at the 10 min post‐dose timepoint on Day 1 INCLUSION CRITERIA: 1. Male and female adults aged =18 and =75 2. Body mass inde X(BMI) within the range of 18.0 to 35.0 kg/m2 3. Physician‐diagnosed asthma >6 months and diagnosis before 50 years 4. Stable asthma therapy: a stable treatment with medium/high doses of ICS+LABA+LAMA (fixed or free combination) or medium/high doses of ICS+LABA (fixed or free combination) for at least 4 weeks before screening 5. Asthma control: controlled or partly controlled based on an Asthma Control Questionnaire (ACQ‐7) score <1.5 at screening and at randomization; 6. Pre‐bronchodilator 40% < FEV1 < 90% of their predicted normal value, after appropriate washout from bronchodilators, at the screening and randomization; 7. Subjects with a positive reversibility test at screening defined as an increase = 12% and/or 200 mL within 15‐20 minutes after inhalation of 400mcg salbutamol [ NOTE: in case the bronchodilator (BD) response threshold is not met at screening, the spirometry test can SECONDARY OUTCOME: 1. Relative change from pre‐dose in FEV1 at all the post‐dose timepoints at each study visit on Day 1, Day 7 and Week 12: 20 min, 30 min, 1 h and 2 h post‐dose Day 7, Week 4 and Week 12: 10 min post‐dose; 2. Absolute change from pre‐dose in FEV1 at all post‐dose timepoints at each study visit on Day 1, Day 7, and Week 12: 10 min, 20 min, 30 min, 1 h, and 2 h post‐dose Week 4: 10 min post‐dose; 3. Number and percentage of subjects with a relative decrease from pre‐dose in FEV1 at each post‐dose timepoint and at any post‐dose timepoint > 15% at each study visit on Day 1, Day 7, and Week 12: 10 min, 20 min, 30 min, 1 h, and 2 h post‐dose Week 4: 10 min post‐dose; 4. Absolute and relative changes from baseline i.e., pre‐dose* FEV1 at Day 1. in pre‐dose* FEV1 at all clinical visits; 5. Change from pre‐dose in FEV1 area under the curve from time zero to 2 h (AUC0‐2h. on Day 1, Day 7 and Week 12; 6. Change from baseline at each inter‐visit period and over the entire treatment period in morning and evening peak expiratory flow rate (PEF); 7. Change from baseline at each inter‐visit period and over the entire treatment period in the percentage of days without the intake of rescue medication; 8. Change from baseline at each inter‐visit period and over the entire treatment period in the average daily use of rescue medication (number of inhalations/day); 9. Change from baseline at each inter‐visit period and over the entire treatment period in the average daily symptoms ; 10. Change from baseline in ACQ‐7 at each study visit; 11. AEs and adverse drug reactions (ADRs); 12. AEs of particular interest: cough, dysphonia, paradoxical bronchospasm, hypersensitivity reactions, severe asthma exacerbations according to ATS/ERS criteria; 13. Vital signs (systolic and diastolic blood pressure); 14. 12‐lead ECG parameters: heart rate (HR), QTcF, PR interval (PR) and QRS interval (QRS); 15. 12‐lead ECG abnormalities ; 16. Standard haematology and blood chemistry (including serum potassium and plasma glucose); 17. Chemistry in urine (quantitative [proteins] and qualitative [ketones and microscopic examination of the sediments])