Key Inclusion Criteria:
1. Age 18-75 years (inclusive), both males and females;
2. BMI requirements at screening: for obese participants, BMI ≥28 kg/m² with or without comorbidities; or for overweight participants, BMI ≥24.0 kg/m² and \<28 kg/m² with at least one of the following comorbidities: hypertension, prediabetes, dyslipidemia, weight-bearing joint pain (as determined by the investigator, excluding joint pain caused by other diseases), obstructive sleep apnea syndrome, or metabolic dysfunction-associated steatotic liver disease;
3. Body weight change \<5% (based on participant self-report, calculated as \[maximum weight - minimum weight\] / maximum weight, with the result rounded to one significant digit) during the 3 months prior to screening, while on diet and exercise control (based on participant self-report).
Exclusion Criteria:
1. Type 1 diabetes, type 2 diabetes, or other specific types of diabetes (excluding gestational diabetes);
2. Secondary obesity, history of bariatric surgery;
3. Presence of gastrointestinal diseases affecting drug absorption, dysphagia;
4. Personal/family history of medullary thyroid carcinoma, C-cell hyperplasia, or multiple endocrine neoplasia type 2; uncontrolled hyperthyroidism or hypothyroidism without standard stable management; thyroid nodule with TI-RADS grade 4 or above;
5. History of acute pancreatitis, chronic pancreatitis, or pancreatic injury within 6 months prior to screening (high-risk pancreatic conditions); acute cholecystitis within the past 3 months, or current cholecystitis, cholangitis, cholelithiasis, or other high-risk gallbladder diseases (except for those with prior cholecystectomy and judged eligible by the investigator);
6. Severe unstable psychiatric disorder, depression, or history of suicide attempt; score ≥15 on the Patient Health Questionnaire-9 (PHQ-9) at screening, or presence of suicidal ideation/suicidal behavior indicated by the Columbia-Suicide Severity Rating Scale (C-SSRS);
7. Any of the following abnormal clinical laboratory results (local laboratory) at screening: anemia (hemoglobin \<110 g/L for males, \<100 g/L for females); liver enzymes, bilirubin, amylase, or lipase exceeding the specified multiples of the upper limit of normal; calcitonin ≥50 ng/L (pg/mL); estimated glomerular filtration rate (eGFR) \<60 mL/min/1.73m²; triglycerides \>5.65 mmol/L; thyroid-stimulating hormone \>6 mIU/L or \<0.4 mIU/L;
8. Uncontrolled hypertension (systolic blood pressure ≥160 mmHg and/or diastolic blood pressure ≥100 mmHg);
9. Abnormal heart rate on resting electrocardiogram, atrioventricular block, prolonged QTcF interval, bundle branch block, or other clinically significant arrhythmias; history of myocardial infarction, unstable angina, severe cardiac insufficiency, coronary intervention/bypass, or other cardiovascular/cerebrovascular diseases within 6 months prior to enrollment;
10. Use of weight-loss drugs or weight-loss herbal medicines, any hypoglycemic agents, antidepressants, antipsychotics, antiepileptics, or lithium salts within 3 months prior to screening; use of systemic glucocorticoids (except for continuous cumulative use \<7 days); active autoimmune disease requiring systemic glucocorticoid therapy during the study period.
