PT027 Compared to PT007 in Patients With Asthma With Mannitol-induced Acute Airway Obstruction

This is a multi-center, randomized, double-blind, 2-period, cross-over study evaluating efficacy and safety of repeated doses of PT027 (albuterol/budesonide pressurized metered dose inhaler (pMDI)) compared to PT007 (albuterol pMDI) in participants with asthma and acute airway obstruction induced by 2 mannitol challenges at least 8 hours apart. It is a two-part study where Part 1 will enroll a small cohort of participants and will be used as a pilot study. The data obtained from Part 1 will be assessed by an internal AstraZeneca advisory board, and suggested changes may be made to Part 2 of the study. The following is the sequence of study visits: (i) Visit 1 (V1) screening (ii) Visit 2 (V2) 10 to 14 days after Visit 1 assessments; 1st dual challenge and treatment visit (iii) Visit 3 (V3) 10 to 14 days after Visit 2; 2nd dual challenge and treatment visit At Visit 1, all participants will be subjected to a single mannitol challenge to establish a positive response (defined as a ≥15% decrease in forced expiratory volume in the first second \[FEV1\] from the 0 mg mannitol FEV1 value) and will receive 4 puffs of open-label PT007. At Visit 2, participants will be randomized to one of 2 treatment sequences, A/B or B/A, where treatments A and B are defined as: (i) Treatment A = PT027 (ii) Treatment B = PT007 For treatment sequence A/B, participants will receive repeated inhalations of PT027 at Visit 2 followed by repeated inhalations of PT007 in Visit 3 . For treatment sequence B/A, participants will receive repeated inhalations of PT007 at Visit 2 followed by repeated inhalations of PT027 in Visit 3. Participants will have a Follow-up Telephone call 7 days after Visit 3/after Early discontinuation (ED).