The purpose of this study is to assess the PD equivalence of the approved asthma combination therapy, BDA, delivered using the proposed replacement propellant HFO compared with BDA delivered using the currently approved propellant HFA in participants with asthma.

The purpose of this study is to assess the PD equivalence of the approved asthma combination therapy, BDA, delivered using the proposed replacement propellant HFO compared with BDA delivered using the currently approved propellant HFA in participants with asthma.

The study duration for each participant will be approximately 14 to 15 weeks and will consist of:

1. A screening and placebo run-in period of approximately 2 weeks prior to the first dose of study intervention
2. 3 treatment periods of 4 weeks each
3. A final safety follow-up visit via telephone contact approximately 5 days after the final dose of study intervention

Participants will attend in-clinic visits 2 weeks apart during the screening/run-in period (Visits 1 and 2) and then every 4 weeks during the treatment period (Visits 3, 4, and 5).

Inclusion Criteria:

• Participant must be ≥ 18 years of age at the time of signing the ICF.
• Participants who have physician diagnosed asthma as defined by GINA for at least 12 months prior to Visit 1.
• Eligible participants are on either a) no daily inhaled maintenance therapy or b) daily inhaled maintenance therapy with low-dose ICS or low-dose ICS-LABA. Participants who are on low-dose ICS maintenance therapy are required to be stable on therapy for a minimum of 3 months prior to Visit 1; participants using low-dose ICSLABA maintenance regimens are required to be stable on therapy for a minimum of 6 months prior to Visit 1.
• Participants with a pre-bronchodilator FEV1 of ≥ 60% and < 90% predicted normal at Visit 1 or Visit 1a.
• Participants with a pre-dose FEV1 of ≥ 60% and < 90% predicted normal at Visit 2 that is within ± 20% of their Visit 1 pre-bronchodilator FEV1.
• Participants who demonstrate bronchodilator responsiveness defined as a > 12% and > 200 mL increase in FEV1 relative to baseline following administration of study provided SABA at Visit 1 or Visit 1a.
• Participants able to demonstrate acceptable spirometry performance as defined by the acceptability and repeatability criteria in the ATS/ERS Standardization of Spirometry 2019 update
• Participants who are willing and, in the opinion of the investigator, able to adjust current asthma therapy, as required by the protocol.
• Participants with a body mass index < 40 kg/m2.
• Females must not be of childbearing potential or, if of childbearing potential, using a form of birth control

Exclusion Criteria:

• Confirmed or suspected diagnosis of COPD or clinically significant non-asthma airway/lung disease.
• Systemic corticosteroid use (eg, prednisone for 3 or more days or a single depo-injectable dose of corticosteroids) for any respiratory, immune, or allergy-attributed disease within 6 months prior to Visit 1.
• An upper respiratory infection requiring antibiotic treatment that is not resolved within 7 days prior to Visit 1.
• A lower respiratory infection in the 4 weeks prior to Visit 1.
• Life-threatening asthma defined as any history of significant asthma episode(s) requiring admission to an intensive care unit, positive pressure ventilation associated with hypercapnia, respiratory arrest, hypoxic seizures, or asthma-related syncopal episode(s) within 5 years of Visit 1.
• Hospitalization due to asthma within 12 months or systemic corticosteroid usage (eg, prednisone for 3 or more days or a single depo-injectable dose of corticosteroids) for asthma within 6 months prior to Visit 1.
• A severe asthma exacerbation during the run-in period
• An ePRO device alert during the run-in period with investigator-confirmed worsening asthma symptoms
• Historical or current evidence of a clinically significant disease including, but not limited to: cardiovascular (eg, congestive heart failure, known aortic aneurysm, clinically significant cardiac arrhythmia, coronary heart disease), hepatic, renal, hematological, neuropsychological, endocrine (eg, uncontrolled diabetes mellitus, uncontrolled thyroid disorder, Addison's disease, Cushing's syndrome), or gastrointestinal (eg, poorly controlled peptic ulcer, gastroesophageal reflux disease) disorders. Significant is defined as any disease that, in the opinion of the investigator, would put the safety of the participant at risk through study participation or that could affect the efficacy or safety analyses if the disease/condition exacerbated during the study.
• Unresectable cancer that has not been in complete remission for at least 5 years prior to Visit 1
• Hospitalization for psychiatric disorder or attempted suicide within 1 year of Visit 1.
• Known history of drug or alcohol abuse within 12 months of Visit 1 or known abuse at any time during the study.

Qualified researchers can request access to anonymized individual patient-level data from AstraZeneca group of companies sponsored clinical trials via the request portal Vivli.org. All requests will be evaluated as per the AZ disclosure commitment: https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure. Yes, indicates that AZ are accepting requests for IPD, but this does not mean all requests will be shared.

AstraZeneca will meet or exceed data availability as per the commitments made to the EFPIA PhRMA Data Sharing Principles. For details of our timelines, please rerefer to our disclosure commitment at https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure.

When a request has been approved AstraZeneca will provide access to the anonymized individual patient-level data via secure research environment Vivli.org.

Signed Data Usage Agreement (non-negotiable contract for data accessors) must be in place before accessing requested information.

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