Idiopathic pulmonary fibrosis (IPF) is a condition where the lungs are damaged and scarred with unknown reason, making breathing becomes increasingly difficult.. REGEND001, made from airway basal cells with ability to regenerate lung tissue, is promising to IPF treatment. In this study, a single-armed clinical trial is ongoing to assess the safety and tolerability of REGEND001 in treatment of IPF. Different doses of REGEND001 is evaluated to establish a dose-response relationship and to suggest appropriate dose for subsequent clinical trials.

Inclusion Criteria:

• Male or female, aged between 50 to 75.
• Diagnosis of IPF according to 2018 Idiopathic Pulmonary Fibrosis Diagnostic Guidelines.
• Participants with 30%~79% of the predicted value in diffusing capacity for carbon monoxide (DLCO) and more than 50% of the predicted value in forced vital capacity (FVC) in pulmonary function tests within 3 months before screening.
• Participants with typical HRCT images of IPF in the past 12 months.
• Participants tolerant to bronchofiberscopy.
• Participants fully informed with the purpose, method and possible discomfort of the trial, agreeing to participate in the trial and signing the informed consent voluntarily.
• Participants with good adherence, willing to take medication and regular follow-up examinations as required by the protocol.
• Participants able to understand and cooperate with the completion of pulmonary function tests.

Exclusion Criteria:

• Participants who cannot tolerate cell therapy.
• Pregnant or lactating women.
• Participants with syphilis or any of human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV) positive antibody; of which stable HBV carriers after drug treatment and cured hepatitis C patients can be enrolled.
• Participants with malignant tumors or a history of malignant tumors.
• Participants with a history of long-term use of drugs known to cause pulmonary fibrosis, such as amiodarone before screening.
• Participants with lung infections or other infections, including bacterial and viral infections, with requirement of intravenous medications before cell transplantation.
• Participants with a history of invasive or noninvasive mechanical ventilation within 4 weeks.
• Participants with any of the following lung diseases: asthma, active tuberculosis, pulmonary embolism, pneumothorax, pulmonary hypertension, pneumoconiosis, etc.; lung cancer, bronchiolitis obliterans or other active lung disease; pneumonia currently or in the past 4 weeks; pneumonectomy previously.
• Requirement of oxygen therapy for more than 15 hours per day.
• Suffering from serious diseases of other system.
• leukopenia or agranulocytosis of any cause; blood creatinine > 2.5 times the upper limit of normal; alanine transaminase (ALT) and aspartate transaminase (AST) > 2.5 times the upper limit of normal in the laboratory tests.
• Participants with a history of mental illness, suicide risk, epilepsy or other central nervous system disorders.
• Severe arrhythmias (such as ventricular tachycardia, frequent supraventricular tachycardia, atrial fibrillation, atrial flutter, etc.) or atrioventricular block of degree II or above, shown by 12-lead Electrocardiogram (ECG).
• Participants with a history of abusing alcohol or illicit drug.
• Participants allergic to cattle products.
• Participants in other clinical trials in the past 3 months.
• Participants with poor compliance and difficult to complete the trial.
• Investigators, employees of research centers or family members of them (none of whom are suitable to participate in the trial to ensure the objectivity of the research);
• Participants with a history of hospitalization owing to acute exacerbation of IPF or other respiratory diseases three or more times within the past year.
• Participants who is taking or is goning to take nintedanib within a month.
• Participants with other acquired or congenital immunodeficiency disorders, or with a history of organ transplantation or cell transplantation therapy.
• Participants whose expected survival may be less than one year judged by the investigator.
• Male participants of childbearing potential and female participants within childbearing age were reluctant to use effective contraception from the time of signing the informed consent to 6 months after cell therapy.
• Participants assessed to be inappropriate in this clinical trial by investigator.