The study is being conducted to evaluate the efficacy and safety of HRS-9821 for patients with COPD, and to explore the reasonable dosage of HRS-9821 for patients with COPD.

Inclusion Criteria:

1. Age ≥ 40 years old and < 80 years old, male or female.
2. Meet the weight standard.
3. Smoking history ≥ 10 pack-years.
4. COPD has been diagnosed ≥ 1 year.
5. 4 weeks before screening, the background treatment for COPD was stable.
6. FEV1/FVC < 0.7, 30% ≤ FEV1 ≤ 80%.
7. mMRC score ≥ 2.
8. The inspection and medication can be completed as required.
9. Non-pregnant and breastfeeding state.
10. Able and willing to provide a written informed consent.

Exclusion Criteria:

1. History of life-threatening COPD.
2. Other pulmonary diseases that may affect the efficacy evaluation of this study.
3. Concurrent diseases other than COPD that may affect lung function.
4. History of asthma.
5. Pulmonary heart disease requiring clinical intervention, or moderate to severe pulmonary hypertension.
6. Malignant tumors within 5 years.
7. Uncontrolled severe cardiovascular and cerebrovascular diseases within 1 year.
8. Unstable diseases.
9. Acute exacerbation of COPD within 12 weeks, hospitalization for COPD or pneumonia within 6 months.
10. Infection in the lungs or other parts occurs within 16 weeks and requires treatment.
11. Immunosuppression.
12. Uncontrolled hypertension.
13. Lung resection, surgical lung volume reduction or endoscopic treatment for COPD.
14. Undergone major surgery or planned surgery within 14 months.
15. Abnormal chest images have clinical significance.
16. Tuberculosis infection requiring treatment within 16 to 12 months.
17. Virological test result was positive.
18. Laboratory blood tests and electrocardiograms were significantly abnormal.
19. Requires oxygen inhalation or intermittent oxygen inhalation therapy.
20. Hypercapnia, using or requiring long-term use of any non-invasive positive pressure ventilation device.
21. Biological agents that may have therapeutic effects on the studied disease have been used within 12 weeks or within 5 half-lives of the drug.
22. Vaccination, theophylline or drugs within 4 weeks.
23. Having participated in other clinical studies within 4 weeks and used research drugs or medical devices containing active ingredients, or still within 5 half-lives of the research drug.
24. Systemic glucocorticoids, immunosuppressants, and oral Roflumilast within 12 weeks.
25. Undergoing or planning rehabilitation treatment for pulmonary rehabilitation.
26. Non-selective β blockers within 1 week.
27. Overly potent/moderately potent drugs that inhibit or induce the liver drug-metabolizing enzyme CYP3A4 within 14 days.
28. Allergic to the research drug or salbutamol or excipients.
29. Has been used HRS-9821.
30. Drug abuse and alcohol abuse within 1 year.
31. Pregnant or lactating period or planning to be pregnant or lactating.
32. The researchers judged that there were other unsuitable circumstances.