Phase I Drug-Drug Interaction Study of UBT251 Injection in Participants With Overweight or Obesity

This is a Phase I, open-label, two-cohort study designed to evaluate the drug-drug interaction potential of multiple-dose UBT251 Injection in adult participants with overweight or obesity. The primary objective of Cohort 1 is to evaluate the effect of UBT251 Injection on the pharmacokinetic (PK) profiles of metformin and warfarin. The secondary objectives of Cohort 1 are to assess the influence of UBT251 Injection on the pharmacodynamic (PD) characteristics of warfarin, to evaluate the safety of UBT251 Injection administered alone, as well as metformin and warfarin administered alone or in combination with UBT251 Injection, and to characterize the PK, PD, and immunogenicity profiles following repeated UBT251 Injection dosing. The primary objective of Cohort 2 is to evaluate the effect of UBT251 Injection on the PK profiles of atorvastatin and digoxin. The secondary objectives of Cohort 2 are to evaluate the safety of UBT251 Injection alone, atorvastatin and digoxin alone, and their combination with UBT251 Injection, as well as to assess the PK, PD, and immunogenicity characteristics after multiple administrations of UBT251 Injection.

Inclusion Criteria: 1. Participants with overweight or obesity, aged 18-45 years inclusive; Cohort 1 includes male participants only, and Cohort 2 includes both male and female participants. 2. Body weight ≥50.0 kg, body mass index (BMI) ranging from 24.0 to 35.0 kg/m² inclusive (BMI = weight(kg)/height²(m²)). 3. Participants (including their partners) have no plan to conceive from screening through 6 months after study completion, are willing to adopt contraceptive measures specified in the study, and have no plan to donate sperm or ova within 6 months after trial completion. 4. Participants are able to communicate well with investigators, have fully understood this study, voluntarily participate in it, understand and comply with all study requirements, and provide written informed consent. Exclusion Criteria: 1. Known hypersensitivity or intolerance to investigational product or its excipients, or hypersensitivity to other GLP-1, GIP, GCG receptor agonists; or prior history of multiple or severe clinically significant drug hypersensitivity reactions; or active allergic disease or high-sensitivity constitution; 2. History or evidence of any of the following diseases: 1. Personal or family history (first-degree relatives: parents, children or siblings) of medullary thyroid carcinoma (MTC) or multiple endocrine neoplasia type 2 (MEN2); 2. History of malignancy within 5 years prior to screening, except for adequately treated carcinoma in situ of the cervix, basal-cell or squamous-cell skin cancer, radically resected local prostate cancer, and radically resected ductal carcinoma in situ of the breast; 3. History of acute or chronic pancreatitis, pancreatic injury, or pancreatic surgery; 4. History of acute cholecystitis, cholelithiasis or severe gallbladder polyps within 6 months prior to screening, for which the investigator assesses that study participation may increase the participant's risk; 5. History of dysphagia or any gastrointestinal disorder affecting drug absorption; 6. Cardiovascular, respiratory, hepatic, gastrointestinal (including disorders markedly affecting gastric emptying or gastric motility, e.g. severe gastric spasm or pyloric stenosis), endocrine (including but not limited to history of thyroid carcinoma or preneoplastic lesions), hematological, neurological diseases, or muscular degenerative disorders that may significantly affect drug absorption, metabolism or elimination, increase participant risk, or confound data interpretation; 7. History of severe hypoglycemic coma; or ≥3 episodes of blood glucose \1 × ULN; 2. Estimated glomerular filtration rate (eGFR) \