Safety and Efficacy of PA9159 Inhalation Aerosol for the Treatment of Adult Bronchial Asthma

This is a multicenter, randomized, double-blind, parallel, placebo-controlled clinical trial. Subjects of 60 with bronchial asthma are planned to be included in this study. With a ratio of 1: 1: 1: 1 to be randomized allocated to receive PA9159 Inhaler of 60 μg, 120 μg, and 240 μg, or placebo, with 15 subjects in each group. The duration of this study is approximately 42 days, including screening, baseline, treatment observation, and follow-up.