UBT251 Injection Phase II Study (Overweight or Obesity)

Inclusion Criteria: 1. Age between 18 and 75 years, inclusive, of any gender; 2. Body mass index (BMI) ≥28.0 kg/m² or 24.0 kg/m² ≤ BMI \< 28.0 kg/m² accompanied by at least one of the following: a. Prediabetes, hypertension, dyslipidemia, or fatty liver; b. Weight-bearing joint pain; c. Obesity-induced dyspnea or obstructive sleep apnea syndrome; 3. Stable body weight for 3 months prior to screening; 4. No fertility plans from screening to 6 months after study completion, willing to use contraceptive measures, and no sperm or egg donation plans within 6 months after study completion; 5. Fully informed about the study and voluntarily signed the written informed consent form. Exclusion Criteria: 1. Known hypersensitivity to the investigational drug or its formulation excipients, or to other GLP-1 receptor agonist drugs, or a history of clinically significant multiple or severe drug allergies, or current allergic diseases, or high sensitivity constitution; 2. History of use of any of the following drugs or treatments within the specified periods prior to screening: 1) GLP-1 receptor agonists, GLP-1R/GCGR agonists, or GLP-1R/GIPR/GCGR agonists within 3 months before screening; 2) Over-the-counter weight-loss drugs or appetite suppressants within 3 months before screening, or prescription weight-loss drugs or lipolytic injectables within 3 months before screening; 3) Drugs likely to affect body weight (e.g.systemic glucocorticoids, tricyclic antidepressants, antipsychotics, or antiepileptics) for ≥2 consecutive weeks within 3 months before screening or expected during the trial; 4) Antidiabetic drugs (e.g.metformin, SGLT2 inhibitors,thiazolidinediones) within 3 months before screening; 3. History or evidence of any of the following diseases: 1) Diagnosis of type 1 diabetes, type 2 diabetes, or other types of diabetes; 2) History of acute or chronic pancreatitis or pancreatic surgery; 3) Symptomatic gallbladder disease within 2 years before screening (defined as imaging evidence of gallstones with doctor-diagnosed abdominal pain attributable to gallstones); subjects who have undergone cholecystectomy and/or cholelithiasis treatment without long-term complications may participate; 4) Personal or family history of medullary thyroid carcinoma or multiple endocrine neoplasia type 2; 5) Secondary obesity due to disease or medication; 6) History of bariatric surgery (excluding: acupuncture for weight loss, liposuction, or abdominal liposuction performed \>1 year before screening; gastric banding removed \>1 year before screening; intragastric balloon removed \>1 year before screening; duodenal-jejunal bypass sleeve removed \>1 year before screening); 7) History of depression or Patient Health Questionnaire-9 (PHQ-9) score ≥15 at screening; or history of severe mental illness (including suicidal ideation/attempts, schizophrenia, bipolar disorder, etc.); 8) Clinically significant cardiovascular disease within 6 months before screening (defined as: i. Myocardial infarction or unstable angina; ii. Cardiac surgery; iii. Congestive heart failure; iv. Cerebrovascular accident, including stroke/transient ischemic attack; v. Other cardiovascular diseases deemed unsuitable for the trial by the investigator); 9) History of retinal disease; 10) History of severe hypoglycemia or recurrent symptomatic hypoglycemia; 11) Concurrent gastroparesis or other gastrointestinal motility disorders, uncontrolled gastroesophageal reflux disease, or gastrointestinal diseases that increase the risk of adverse events with medication use; 12) Major surgery, severe trauma, or severe infection within 1 month before screening, as judged by the investigator to be unsuitable for the trial; 13) History of malignant tumors; 14) Limb deformities or disabilities that prevent accurate measurement of height, weight, or other indicators; 15) Concurrent diseases (e.g.neurological, endocrine, mental diseases) that, in the investigator's opinion, may affect subject safety, efficacy evaluation, or compliance; 4. Screening abnormalities in any of the following tests: 1) HbA1c ≥6.5% or fasting blood glucose (FBG) ≥7.0 mmol/L; if FBG is 6.1-6.9 mmol/L at screening, an oral glucose tolerance test (OGTT) is required, and subjects with 2-hour post-load blood glucose ≥11.1 mmol/L will be excluded; 2) Hepatic or renal impairment (serum ALT and/or AST ≥3 times the upper limit of normal \[ULN\]; serum total bilirubin ≥1.5×ULN; estimated glomerular filtration rate \[eGFR\] \<60 mL·min-¹·1.73m-² according to local laboratory reference ranges); 3) Serum calcitonin ≥50 pg/mL; 4) Thyroid dysfunction (confirmed by clinical assessment and/or abnormal thyroid-stimulating hormone \[TSH\]) with hyperthyroidism or hypothyroidism that may increase patient risk; 5) Fasting triglycerides ≥5.6 mmol/L; 6) Serum amylase or lipase \>2.0×ULN; 7) International normalized ratio (INR) above the normal range at screening; 8) Hemoglobin \<110 g/L (male) or \<100 g/L (female); 9) Untreated or poorly controlled hypertension; 10) Clinically significant electrocardiogram (ECG) abnormalities at screening; 11) Diagnosis of hypokalemia or hypomagnesemia at screening; 12) Physical examination, vital signs, or laboratory findings with clinically significant abnormalities that, in the investigator's judgment, pose a major risk to the subject or interfere with safety, pharmacokinetic (PK), or pharmacodynamic (PD) result evaluation; 5. Positive hepatitis B surface antigen (HBsAg) with hepatitis B virus (HBV) deoxyribonucleic acid (DNA) above the reference value, positive hepatitis C virus (HCV) antibody with HCV ribonucleic acid (RNA) exceeding the reference range upper limit, positive human immunodeficiency virus (HIV) antibody, or positive syphilis antibody at screening; 6. Blood loss or blood donation exceeding 400 mL within 3 months before screening, or receipt of blood or blood component transfusions; or concurrent hemoglobinopathies, hemolytic anemia, or sickle cell anemia; 7. Participation in other clinical trials within 3 months before screening; 8. History of drug or alcohol abuse, defined as female subjects consuming \>7 standard drinks per week or male subjects consuming \>14 standard drinks per week; 9. Pregnant or lactating women; 10. Inability to tolerate venipuncture or history of fainting or dizziness during blood draws; 11. Other conditions deemed unsuitable for participation in the clinical trial by the investigator.