The study is a Phase II, multicenter, double-blind, randomized, parallel, placebo-controlled clinical trial designed to evaluate the efficacy, safety of 9MW1911 in patients with Chronic Obstructive Pulmonary Disease (COPD).

Inclusion Criteria:

- 1.Male or Female patients must be 40 to 75 years of age inclusive； 2.Physician diagnosis of COPD for at least 1 year at screening； 3.Documented history of >= 2 moderate or >=1 severe COPD exacerbations within 12 months prior to screening.

4.Moderate-to-severe COPD with post-BD FEV1/FVC rato<0.7 and a post-BD FEV1%predicted ≥20% and<80% at screening； 5.Body Mass Index (BMI) of 16 kg/m² to 32 kg/m²； 6.Current tobacco smoker or former smoker with a history of smoking ≥ 10 pack-years 7.Participants with standard of care controller therapy, for ≥3 months prior to Screening and at a stable dose of controller therapy for at least 1 month prior to the screening；

Exclusion Criteria:

• 1.Current diagnosis of asthma or documented history of asthma; 2.Diagnosis of Alpha-1 Antitrypsin Deficiency； 3.History of other clinically significant pulmonary diseases apart from COPD: such as sarcoidosis,interstitial lung diseases, bronchiectasis,cystic fibrosis，constrictive bronchiolitis,severe pulmonary hypertension or other active pulmonary diseases; 4.Long-term treatment with oxygen (oxygen therapy time >15h/day) or mechanical ventilation, or clinically significant apnea requiring continuous positive airway pressure (CPAP) or non-invasive positive pressure ventilation (NIPPV); 5.History of lung pneumonectomy, or lung volume reduction within 12 months prior to screening，or planned to undergo lung volume reduction surgery (LVRS) during the study period; 6.Patients in the acute phase of pulmonary rehabilitation(participating in, or scheduled for a pulmonary rehabilitation program within 4 weeks of screening); 7.Uncured upper or lower respiratory tract infections during the screening period; 8.Moderate to severe COPD exacerbations within 4 weeks prior to screening or during the screening period； 9.Any infection requiring hospitalization for ≥24 hours and/or treatment with oral, IV, or IM antibiotics within 4 weeks prior to screening or during the screening period; 10.Received treatment with oral, IV, or intramuscular (IM) corticosteroids (>10 mg/day prednisone or equivalent dose) within 4 weeks prior to starting study medication; 11.Myocardial infarction, unstable angina within 12 months prior to screening;or heart failure (NYHA Class III or IV) within 6 months prior to screening； 12.History of ventricular arrhythmias or risk factors for ventricular arrhythmias, such as structural heart disease (e.g., severe left ventricular systolic dysfunction, severe left ventricular hypertrophy ), family history of unexplained sudden death or long QT syndrome； 13. experienced transient ischemic attack or stroke within 6 months prior to screening; 14.with unstable cardiovascular diseases, such as pulmonary embolism or deep vein thrombosis that occurred within 6 months before screening, which the researchers believe may put the patient at risk or have a negative impact on the research results; 15.Known active tuberculosis or nontuberculous mycobacterial infection (subjects with positive interferon - γ release assay (IGRA) during the screening period, if evaluated as inactive tuberculosis by the researcher based on clinical manifestations and imaging examinations, etc., can participate in this study); 16.Positive for human immunodeficiency virus antibody (HIV-Ab), or positive for hepatitis B surface antigen (HBsAg) with HBV-DNA copies > 1000 IU/mL or above the upper limit of normal (ULN) of the study center, or positive for hepatitis C virus antibody (HCV-Ab) with HCV-RNA copies above the ULN of the study center, or positive for Treponema pallidum antibody.

  17.With active autoimmune disease or receiving immunosuppressive therapy for an autoimmune diseases (e.g., rheumatoid arthritis, inflammatory bowel disease, primary biliary cirrhosis, systemic lupus erythematosus, multiple sclerosis) are excluded.

  18. with any active malignancy or a history of malignancy (except for low-grade tumors deemed cured ≥5 years before screening, such as cervical carcinoma in situ or basal cell carcinoma).

  19.received a live attenuated vaccine within 4 weeks prior to screening or during the screening period.

  20.received any biologic therapy (e.g., omalizumab, dupilumab, and/or anti-interleukin-5 therapy) within 3 months prior to screening ; 21.received any investigational therapy within 3 months prior to screening or within 5 drug-elimination half-lives, whichever is longer.

  22.Any clinically significant ECG abnormality deemed by the investigator to potentially affect study conduct, such as QTc prolongation (QTcF > 450 ms for males, > 470 ms for females).

  23.Alanine aminotransferase (ALT) >= 2 times the upper limit of normal (ULN); Aspartate aminotransferase (AST) >= 2 times ULN; Total bilirubin >= 1.5 times ULN.

  24.Estimated glomerular filtration rate (eGFR) <60 mL/min/1.73m2. 25.with any serious medical condition or clinically significant laboratory abnormality（in investigator's judgment） that could compromise the subject's safety or ability to participate in or complete the study.

  26. With a history of alcohol abuse and/or substance abuse within 12 months prior to screening.

  27.History of severe hypersensitivity or anaphylactic reactions to any biologic agent, or known hypersensitivity to any component of the investigational drug.

  28. Pregnant or lactating women, Or female paticipants of child-bearing potential with a positive pregnancy test at screening.

  29.Subjects who is inappropriate to participate in the trial due to any reasons as determined by the investigator.