Bioequivalence Study of GZR18 Injection Before and After CMC Change

Inclusion Criteria: 1. Subjects who voluntarily sign the Informed Consent Form (ICF), can receive SC injection, fully understand the content, process and possible adverse reactions of the trial, and are able to follow the regulations on contraindications and restrictions specified in this protocol. 2. Male, 18 to 50 years of age at signing the ICF (both inclusive). 3. Weight ≥ 50 kg and body mass index (BMI) within 19-26 kg/m2 (inclusive) at screening. 4. Subjects of childbearing potential with no birth plan from the signing of ICF to 8 weeks after the last dose, willingness to take effective contraceptive measures, and no plan for sperm donation. \- Exclusion Criteria: 1. Subjects with clinically significant abnormalities detected during the screening period in physical examination, vital signs, laboratory tests, 12-lead ECG, abdominal ultrasound, or chest X-ray, as determined by the investigator. 2. Subjects who test positive for hepatitis B virus surface antigen, hepatitis C virus IgG antibody, human immunodeficiency virus antibody, P24 antigen, or anti-treponema pallidum antibody. 3. Subjects with a history of or existing circulatory, urinary, digestive, respiratory, nervous, endocrine, or psychiatric disorders that, in the investigator's judgment, remain clinically significant. 4. History of acute or chronic pancreatitis and pancreatic injury before screening. 5. History or family history of previous or existing medullary thyroid carcinoma, multiple endocrine neoplasia type 2. 6. Subjects who have used any drugs that alter the activity of drug metabolizing enzymes or transporters within 4 weeks prior to screening, or subjects with acute diseases or concomitant medication from the screening period to before randomization. 7. Subjects with severe infection or unexplained infection within 4 weeks before screening. 8. Major surgery within 6 months prior to screening, or scheduled surgery or hospitalization during the study. 9. Subjects known or suspected to have hypersensitivity to any ingredient of the investigational medicinal product (IMP) (glucagon like peptide-1 receptor agonist (GLP-1RA) or its excipients). 10. Use of any prescription drugs, over-the-counter drugs or Chinese herbal medicine within 2 weeks prior to screening; use of any GLP-1R agonists or drugs with the same mechanism of action to GLP-1R agonists (such as GLP-1R/glucagon receptor \[GCGR\] agonists or gastric inhibitory polypeptide receptor \[GIPR\]/GLP-1R agonists or GIPR/GLP-1R/GCGR agonists) within 3 months prior to screening. 11. Subjects who have been vaccinated within 1 month before screening or are scheduled for vaccination during the study. 12. Blood donation or blood loss greater than or equal to 400 mL within 3 months before screening, or blood donation scheduled during the study or within 8 weeks after the end of the study. 13. History of drug abuse prior to screening; or positive results for drug abuse at screening (D-1). 14. History of alcohol abuse within 3 months prior to screening, defined as an average intake of more than 14 units per week (1 standard unit=360 mL of beer or 150 mL of 12% wine or 45 mL of 40% spirits); or use of any alcohol-containing products 48 hours before administration; or abnormal results for breath alcohol test at screening (D-1). 15. Subjects who smoked more than 5 cigarettes per day on average within the 3 months before screening, or who do not agree to abstain from smoking for the duration of the study. 16. Subjects who engage in strenuous exercise within 48 h before administration of the IMP, or have other factors that may affect drug absorption, distribution, metabolism, or excretion. 17. Subjects who consume grapefruit or grapefruit-containing products, or any caffeinated or xanthine-containing foods or beverages (such as coffee, tea, cola, or chocolate) within 48 hours before administration of the IMP. 18. Subjects who have special dietary requirements and cannot adhere to a standardized diet, or who are lactose intolerant. 19. Subjects with a history of needle phobia and blood phobia, difficulty in blood collection or intolerance to venous blood collection. 20. Subjects who are investigators or employees of the study site, or family members of the employees or investigators. 21. Participation in a clinical study of another IMP or device within 3 months before screening, or within 5 half-lives of the previous IMP (whichever is longer). Or plan to participate in another clinical study of an IMP or device before completing all scheduled assessments in the clinical study. \-