The primary objectives are to evaluate the safety and efficacy of infusion of fully characterized clonally derived fetal mesenchymal stem cells (cfMSCs) for the control of severe symptoms associated with moderate to severe chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease (COPD) is a chronic airway inflammatory disease characterized by persistent airflow limitation, with high morbidity, disability and mortality worldwide. Traditional therapeutic methods such as bronchodilators and anti-inflammatory drugs can only relieve clinical symptoms, delay disease progression, but cannot repair the damaged alveolar and airway tissue structure, so the long-term prognosis is poor.

Clonal fetal mesenchymal stem cells (cfMSCs) are isolated and clonally characterized fetal tissue-derived MSCs with demonstrated low allogeneity and multi-directional differentiation potential, which may modulate lung stromal cells, alveolar epithelial cells and airway epithelial cells to repair the damaged lung tissues and facilitate the regeneration of alveolar and airway structure, thus improving the lung ventilation as well as gas exchange function of the COPD patients. In addition, cfMSCs may secrete a variety of anti-inflammatory factors, growth factors and exosomes to inhibit the excessive inflammatory response in the lung tissue of COPD patients, improve the local microcirculation, and lay a foundation for the repair of damaged lung tissues.

This study aims to evaluate the safety, tolerability and preliminary efficacy of fully characterized cfMSCs in patients with moderate to severe COPD whose prior treatment has been ineffective. The research will provide a new clinical strategy for treating COPD and determine the optimal cell dosage, administration route and long-term therapeutic effect of the stem cell therapy, and open up a new path for the regenerative repair of lung damage caused by chronic respiratory diseases.

Inclusion Criteria:

1. Ability to understand the study protocol and the willingness to provide written informed consent;
2. Age 40-80 years old, male or female;
3. Diagnosed with moderate to severe COPD according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines (GOLD Ⅱ-Ⅳ).
4. Regular use of COPD conventional drugs for more than 3 months, and the condition is stable for more than 4 weeks;
5. ineffective clinical treatment;
6. Life expectancy > 6 months;
7. At least six months smoking cessation, including non-smoking during the treatment and follow-up periods of the study.

Exclusion Criteria:

1. Combined with other serious lung diseases: asthma, active pulmonary tuberculosis, bronchiectasis, pulmonary embolism, interstitial lung disease, pulmonary hypertension, etc.;
2. A history of lung surgery (pneumonectomy, lung volume reduction surgery, etc.) or bronchial intervention surgery within 12 months;
3. Invasive or non-invasive mechanical ventilation history within 4 weeks, or moderate to severe acute exacerbation of COPD within 4 weeks;
4. Negative for HIV, HCV or syphilis serology;
5. A history of malignant tumors or malignant tumors under treatment;
6. Autoimmune diseases requiring long-term use of glucocorticoids or immunosuppressants;
7. Poorly controlled diabetes (fasting blood glucose > 10.0 mmol/L) or severe metabolic diseases;
8. A history of alcohol or drug abuse, or mental diseases that cannot cooperate with the study;
9. Pregnancy or breastfeeding.
10. Unable or unwilling to comply with study specific schedules or procedures.