Bioequivalence Study of Budesonide/Formoterol Inhalation Powder in Healthy Participants

The goal of this study is to learn if a new formulation of Budesonide/Formoterol Inhalation Powder (160μg/4.5μg), manufactured by Shanghai New Huanghe Pharmaceutical Co., Ltd., works the same as the already approved reference product, Symbicort® Turbuhaler® (160μg/4.5μg), in the body. It will also learn about the safety of the new formulation. The main questions it aims to answer are: * How quickly and how much of the study drug gets into the blood after inhalation, compared with the reference product? * What medical problems do participants have when taking the study drug? Researchers will compare the new formulation to the reference product (the already approved treatment) to see if they are bioequivalent. Participants will: * Be randomly assigned to receive either the new formulation or the reference product in the first period, then switch to the other in the second period * Take a single dose of 2 inhalations in each period, with a 4-day washout period between doses * Have 22 blood samples collected over 36 hours after each dose to measure drug levels in the blood * Visit the clinic for checkups, including vital signs, physical examinations, and laboratory tests * Be monitored for any side effects throughout the study