Phase I Trial of Envafolimab for Healthy Male Subjects

Inclusion Criteria: 1. Be able to fully read, understand, and sign the informed consent form; 2. Male subjects aged 18-45 years 3. Clinical examinations in the screening period are normal or abnormal without clinical significance; 4. A body mass index (BMI) in the range of 19 to 26 kg/m22, and a body weight between 50 and 85 kg; 5. Use effective contraceptive methods from the beginning of the informed consent to 5 months after the use of the drug, and have no plans to give birth or donate sperm. Exclusion Criteria: 1. Systolic blood pressure ≥140 mmHg/ diastolic blood pressure ≥90 mmHg or systolic blood pressure \< 90 mmHg/ diastolic blood pressure \< 60 mmHg, pulse \> 100 beats /min or \< 50 beats /min at screening or baseline examination; 2. QT interval (QTcF) ≥450; 3. Estimated glomerular filtration rate eGFR \< 90 ml/min/1.73m2; 4. Thyroid function beyond the normal range; 5. ALT \> ULN Or AST \> ULN; 6. Prior treatment with a PD-1/L1 inhibitor; 7. Have taken any prescription drug, over-the-counter drug, any vitamin product or herbal or health product within 14 days prior to study drug administration; 8. Had a history of upper respiratory tract infection or other acute infection within 14 days prior to study drug administration; 9. Positive hepatitis B surface antigen, hepatitis C antibody, or human immunodeficiency virus antibody or syphilis.