A Study Testing the Superiority of CHF 1535 pMDI 800/24µg Total Daily Dose Compared With CHF 718 pMDI 800µg Total Daily Dose in Adults With Asthma on Medium or High-Dose Inhaled Corticosteroid

Inclusion Criteria (IC):

• Informed consent: A signed and dated written informed consent obtained prior to any study-related procedures.
• Sex and age: Male or female aged ≥18 and ≤75 years.
• Diagnosis of asthma: A documented history of asthma for at least 1 year, with onset before age 40
• Stable asthma therapy: Use of medium-dose ICS with or without a LABA or high-dose ICS alone for 3 months (at a stable dose for at least 4 weeks prior to screening).
• Lung function: Subjects with a pre-bronchodilator FEV1 ≥40% and ≤85% of predicted, after appropriate washout from bronchodilators, at the screening and randomization visits. In addition, the absolute value of the first pre-dose FEV1 at randomization (V2) must be at least 80% of the pre-bronchodilator value attained at screening.
• Reversibility post-bronchodilator: Subjects with a positive reversibility to bronchodilator at screening, defined as an increase in FEV1 > 12% and > 200mL compared to baseline within 30 minutes after 4 inhalations of albuterol hydrofluoroalkane (HFA) pMDI 90µg/actuation.

Note for IC#5 and IC#6: In case the reversibility and/or quality threshold is not met at screening, the test can be performed once before randomization.

• Female subjects:

a. Women of childbearing potential (WOCBP) fulfilling one of the following criteria: i. WOCBP with fertile male partners: they and/or their partner must be willing to use a highly effective birth control method from the signing of the informed consent form and until the follow-up contact or ii. WOCBP with non-fertile male partners (contraception is not required in this case).

b. Female subjects of non-childbearing potential defined as physiologically incapable of becoming pregnant (i.e. post-menopausal or permanently sterile as per definitions given in Appendix 2). Tubal ligation or partial surgical interventions are not acceptable. If indicated, as per investigator's request, post-menopausal status may be confirmed by follicle-stimulating hormone levels (according to local laboratory ranges).

• Cooperative attitude and ability to demonstrate correct use of the pMDI inhalers and eDiary/peak flow meter.

Exclusion Criteria

• Pregnancy or lactation: where pregnancy is defined as the state of a female after conception and until termination of the gestation, confirmed by a positive pregnancy test (serum and urine pregnancy test to be performed at screening visit and urine pregnancy test to be performed prior to randomization).
• Poor compliance with run-in medication or eDiary completion 450ms for males or QTcF >470ms for females at screening or at randomization visits (criterion not applicable for subject with pacemaker or permanent atrial fibrillation).
• Other medical conditions: Other active severe acute or chronic medical or psychiatric condition or laboratory abnormality that may increase the risk associated with study participation or study drug administration or may interfere with the interpretation of study results and, in the judgment of the investigator, would make the subject inappropriate for entry into this study.
• Vaccination: Subjects having received a vaccination within 2 weeks prior to screening or during the run-in period.
• Subjects' wellbeing: Subjects mentally or legally incapacitated, including but not limited to subjects who are institutionalized or incarcerated.
• Hypersensitivity: Subjects with known intolerance, hypersensitivity or contraindication to treatment with ß2-agonists, ICS, or propellant gases/excipients.
• Surgery: Subjects with major surgery in the 3 months prior to the screening visit or planned surgery during the study.
• Additional treatment: Subjects treated with non-potassium sparing diuretics (unless administered as a fixed-dose combination with a potassium conserving drug or changed to potassium sparing before the screening), non-selective beta-blocking drugs, quinidine, quinidine-like anti-arrhythmic, or any medication with a QTc prolongation