A Study of PMG1015 Injection in Idiopathic Pulmonary Fibrosis Subjects

Inclusion Criteria: 1. Able to understand the study procedures and method, willing to complete the study as required by the clinical study protocol, and sign the ICF; 2. Males or females, aged between 40 and 85 years of age, inclusive at signature of ICF. 3. Body weight ≥ 50 kg for males and ≥40 kg for females; 4. Diagnosis of IPF (HRCT diagnosis of UIP pattern/probable UIP pattern [as reviewed and confirmed by experts from independent imaging review team] with or without a pathologic diagnosis of UIP pattern/probable UIP pattern; if HRCT diagnosis is indeterminate for UIP, then a pathologic diagnosis of UIP pattern/probable UIP pattern is required) as defined by current American Thoracic Society (ATS)/European Respiratory Society (ERS)/Japanese Respiratory Society (JRS)/Latin American Thoracic Association (ALAT) Clinical Practice Guidelines for IPF (2022) (Pathological examination refers to transbronchial lung cryobiopsy or surgical/pleuroscopic lung biopsy); 5. Forced vital capacity percent predicted (FVCpp) ≥45% at screening; 6. Diffusing capacity of the lung for carbon monoxide (DLCO; corrected for haemoglobin) from 30% to 90% of the predicted, inclusive at screening; 7. Patients not receiving any approved IPF treatment (Pirfenidone or Nintedanib) for any reasons within 1 month before randomization, including those who were not tolerant or responsive to prior treatment with approved drugs (Pirfenidone or Nintedanib), or those who disagree to receive the approved IPF treatment after discussion with the investigator on the risks or benefits of such medications (Note: It's not allowed for any subject to discontinue the approved IPF treatment for inclusion into this study). Exclusion Criteria: 1. Patients with instable condition of IPF as assessed by the investigator at screening, and those with acute exacerbation of IPF during screening or within 3 months prior to randomization; 2. Patients who are likely to be lung transplant recipients within 6 months or expected to survive less than 1 year as assessed by the investigator at screening; 3. Patients with range of emphysema more than that of pulmonary fibrosis as indicated by chest HRCT (conclusion from independent imaging review shall prevail) at screening; 4. Patients accompanying with obstructive airway diseases (such as FEV1/FVC < 0.7 after bronchodilator therapy); 5. Patients accompanying with an interstitial lung disease other than IPF; 6. Patients accompanying with other types of respiratory disorders, which may affect the study results as assessed by the investigator; 7. Patients who require ≥ 15 hours of daily oxygen therapy; 8. Oxygen saturation at rest in room air measured by a finger pulse oximeter <90% (0-1500 meters above the sea level) or <85% (>1500 meters above the sea level) at screening; 9. Patients who received corticosteroids (Prednisone Acetate Tablets > 15 mg/day or an equivalent dose of other corticosteroids) within 1 month prior to screening; 10. Patients who received any cytotoxic drug, immunosuppressant, cytokine regulator, or receptor antagonist (including but not limited to Methotrexate, Azathioprine, Mycophenolate Mofetil, Cyclophosphamide, Cyclosporin) within 4 weeks prior to screening; 11. Patients who received vasodilator therapy for pulmonary arterial hypertension (e.g. Bosentan) within 1 month prior to screening; 12. Patients accompanying with other uncontrolled underlying diseases (congestive heart failure, acute myocardial infarction, unstable angina pectoris, hemorrhagic stroke, or ischemic stroke categorized as New York Heart Association [NYHA] Class III, or IV, as well as pulmonary arterial hypertension requiring intervention within 6 months prior to screening), for which the patient is not considered suitable for the study as assessed by the investigator; 13. Patients who had active tuberculosis within 12 months prior to screening, or clinical symptoms of bacterial, viral, fungal or microbial infections requiring intervention within 4 weeks prior to randomization; 14. Patients with coronavirus disease-2019 (COVID-19) diagnosis within 1 month prior to screening and/or at screening (COVID-19 nucleic acid test is not a required procedure of the study, but may be performed if necessary); 15. Patients who were vaccinated or plan to get vaccinated against COVID-19 and other diseases within 1 month prior to screening and up to 1 month after the last dose; 16. Patients with history of malignancies (excluding recovered basal cell carcinoma and cervical carcinoma in situ) within 5 years prior to screening, or under evaluation of any potential malignancies; 17. Alanine Aminotransferase (ALT) or Aspartate Aminotransferase (AST) ≥ 2×Upper Limit of Normal (ULN) or Total Bilirubin ≥1.5×ULN; 18. Serum creatinine ≥1.5×ULN; 19. Patients with active hepatitis, syphilis, or positive for HIV antibody; 20. Patients who had a major surgery (under general anesthesia) within 3 months prior to screening, or plan to undergo a surgery during the study, which may affect the evaluation of the study endpoints as assessed by the investigator; 21. Patients who participated in any clinical trials (of, including, other investigational drugs/devices) within 3 months prior to screening, or within 5 half-lives at screening; 22. A former smoker who quitted for ≤ 3 months, or unable to quit smoking throughout the study; 23. A suspected or confirmed alcohol or drug abuser; 24. Patients who have known allergic reaction to the investigational product or its APIs, or history of allergic reaction to human, humanized, chimeric, or murine monoclonal antibodies or any substances contained in the excipients; 25. Pregnant or lactating women; female subjects who plan to become pregnant during the study, or patients who are not willing to take contraceptive measures as required by the protocol during the study; 26. Other conditions that preclude the patient from participating in the study as assessed by the investigator.