A Study to Assess the Efficacy and Safety of Budesonide/Albuterol Metered-dose Inhaler (BDA MDI/PT027) in Adults and Children 4 Years of Age or Older With Asthma

Inclusion Criteria: 1. Female or male aged ≥4 years at the time of informed consent 2. Physician diagnosis of asthma documented for at least 1 year 3. Receiving 1 of the following scheduled asthma maintenance therapies for 3 months with stable dosing for at least the last 4 weeks before Visit 1: * Medium-to-high-dose inhaled corticosteroid (ICS) * Medium-to-high-dose ICS and 1 additional maintenance therapy from the following: leukotriene receptor antagonists (LTRA), long-acting muscarinic antagonists (LAMA), or theophylline * Low-to-high-dose ICS in combination with long-acting β2-adrenoreceptor agonist (LABA) with or without one additional maintenance therapy from the following: LTRA, LAMA, or theophylline 4. Prebronchodilator forced expiratory volume in 1 second (FEV1) of ≥40 to \<90% predicted normal value for adults and adolescents, and ≥60 to \<100% predicted normal value for subjects aged 4 to 11 years after withholding specified medications including short/rapid-acting β2-adrenoreceptor agonist (SABA) 5. Demonstrate reversibility at Visit 1, with an increase in FEV1 ≥12% (and ≥200 mL for subjects aged ≥18 years) relative to baseline after administration of sponsor provided Ventolin via central spirometry. One re-test for reversibility testing is allowed within the screening period in advance of Visit 2 6. Demonstrate acceptable spirometry performance (i.e., meet American Thoracic Society/European Respiratory Society acceptability/repeatability criteria) 7. A documented history of at least 1 severe asthma exacerbation within 12 months before Visit 1 8. Able to perform acceptable and reproducible peak expiratory flow (PEF) measurements as assessed by the investigator Exclusion Criteria: 1. Chronic obstructive pulmonary disease or other significant lung disease (e.g., chronic bronchitis, emphysema, bronchiectasis with the need of treatment, cystic fibrosis, or bronchopulmonary dysplasia) 2. Oral corticosteroid/SCS use (any dose and any indication) within 6 weeks before Visit 1 3. Chronic use of oral corticosteroids (OCS, ≥3 weeks use in 3 months prior to Visit 1) 4. Having received any marketed (e.g., omalizumab, mepolizumab, reslizumab, benralizumab) or investigational biologic within 3 months or any other prohibited medication 5. Current smokers, former smokers with \>10 pack-years history, or former smokers who stopped smoking \<6 months before Visit 1 (including all forms of tobacco, e-cigarettes \[vaping\], and marijuana) 6. Life-threatening asthma defined as any history of significant asthma episode(s) requiring intubation associated with hypercapnia, respiratory arrest, hypoxic seizures, or asthma related syncopal episode(s) within 5 years of Visit 1 7. Historical or current evidence of a clinically significant disease 8. Cancer not in complete remission for at least 5 years 9. Hospitalization for psychiatric disorder or attempted suicide within 1 year of Visit 1 10. History of psychiatric disease, intellectual deficiency, poor motivation, or other conditions if their magnitude is limiting informed consent validity 11. Significant abuse of alcohol or drugs