This trial is conducted in China. The purpose of this study is to evaluate the pharmacokinetic similarity of Tafolecimab with different manufacturing process in healthy male subjects. Another purpose is to determine safety, and immunogenicity of sintilimab with different manufacturing process,also to determine Pharmacodynamics of Tafolecimab with different manufacturing process

Inclusion Criteria:

1. Male subjects between 18 and 65 years of age, inclusive.
2. Low-density lipoprotein cholesterol (LDL-C) within the range of 1.8 mmol/L to 4.9 mmol/L, inclusive, at screening.
3. Body weight within the range of 63.0 kilograms (kg) to 75.0 kg, inclusive.
4. Subjects who are willing maintain current normal diet and physical activity.
5. Subjects agree to use reliable contraceptive measures (such as abstinence, sterilization, contraceptives, injectable contraceptive medroxyprogesterone or subcutaneous implant contraception, etc.) during the study period and within 6 months after the study drug infusion.
6. No history of serious diseases, including (but not limited to) cardiovascular, hepatic, renal, gastrointestinal, psychiatric, neurologic, endocrine, pulmonary, hematological, immune disease.
7. Subjects voluntarily signed the informed consent form and agreed to strictly follow the requirements of this protocol.

Exclusion Criteria:

1. Subjects who have a history of allergy, or may be allergic to the investigational drug and the related compounds.
2. Have used the inhibitors of proprotein convertase subtilisin type 9 (PCSK-9).
3. Have clinically relevant abnormalities identified by Vital signs, physical examination, clinical laboratory tests, 12-lead ECG, or chest X-ray, at screening.
4. Unwilling to stop any strenuous physical activity (such as weightlifting or long-distance running) within 72 hours before the planned follow-up visit.
5. History of hospitalization within 1 month before screening, major surgery within 6 months before screening, or other unstable conditions judged by the investigator.
6. The last dose of the previous investigational product which is chemical drug has been given in less than 1 month before administration.
7. The last dose of the previous investigational product which is biological drug has been given in less than 3 months before administration.
8. Have used any drugs (including over-the-counter drugs or prescription drugs), the last medication is less than 14 days or the last medication is less than 5 half-lives of the drug from the administration day (whichever is longer), or are using any drugs.
9. Have used any traditional Chinese medicines, vitamins or drugs or supplements known to affect lipid metabolism within 30 days before administration.
10. Have a positive test result of human immunodeficiency virus (Human Immunodeficiency Virus, HIV) antibody, hepatitis B virus surface antigen (HBsAg), Hepatitis C virus (HCV) antibody or syphilis test at screening.
11. History of alcohol or drug abuse results within 12 months before screening. Average daily alcohol intake is more than 3 units of alcohol (male) (1 unit≈360mL beer, or 45mL spirits with 40% alcohol content, or 150mL wine), or unwilling to stop drinking 72 hours before administration and throughout the study period, or a positive ethanol breath test at screening, or positive drug screening results by urine at screening.
12. unable to abstain from smoking, alcohol and caffeinated beverages within 72 hours before administration and throughout the study period.
13. lost blood, donated blood ≥200 ml within 2 months before screening.
14. History of organ transplantation or malignant tumor.
15. Not suitable for this study in the investigator's opinion.