A Study of SYH2069 Injection in Healthy Participants

Inclusion Criteria: * Fully understand the content, process and possible adverse reactions of the trial, and voluntarily sign the informed consent form before the trial; * Male or female, aged 18-55 years (inclusive, based on the time of signing the informed consent form) at screening; * At screening, male body weight ≥ 50 kg, female body weight ≥ 45 kg, SAD study: BMI between 19 and 28 kg/m2 inclusive), MAD study: BMI between 24 and 35 kg/m 2 inclusive); * Subjects (including partners) have no plans to have children from the time of signing the informed consent form until 6 months after the last dose, and agree to use highly effective contraceptive measures specified in the protocol. Exclusion Criteria: * Known or suspected allergies to GLP-1 or GIP receptor agonists or any components of the investigational product, or allergic constitution (allergies to multiple drugs and foods); * Abnormal results of vital signs, physical examination, laboratory tests, chest X-ray, ultrasound, and electrocardiogram, etc., which are judged by the investigator to be clinically significant and unsuitable for participation in the study. Among them, the following conditions were not excluded in the MAD study: (1) systolic blood pressure \<160 mmHg, diastolic blood pressure \<100 mmHg; (2) TG ≤ 3.42 mmol/L, TC ≤ 7.75 mmol/L (regardless of whether LDLC is abnormal), and abnormal HDLC; (3) ALT \< 2 times × upper limit of normal, AST \< 2 times × upper limit of normal, GGT \< 2.5 times × upper l…