A Phase Ia/Ib Clinical Trial of IBI360 Monotherapy or in Combination With Sintilimab and (or) Chemotherapy in Advanced or Metastatic Solid Tumors

Inclusion Criteria: 1. Provide signed informed consent; 2. Male or female aged at 18-75 (inclusive) years; 3. Expected survival ≥12 weeks; 4. ECOG PS score 0 or 1; 5. Provide archival or fresh tissues for CLDN18.2 expression analysis; 6. Adequate laboratory parameters; 7. Suffer from advanced or metastatic malignant local solid tumors confirmed by histological diagnosis and meet the criteria of the enrolled group as follows: Ia: The subjects for whom no standard treatment regimens are available or who is intolerable to standard treatments. Ib: pancreatic carcinoma, HER2 negative gastric adenocarcinoma, advanced or metastatic solid tumors Exclusion Criteria: 1. The subjects who received the treatment with CLDN18.2 monoclonal antibody or CLDN-18.2 CART; 2. The subjects who received other anti-tumor medication within 4 weeks prior to the initial dose of the study drug; 3. Any toxicity due to previous anti-tumor therapy that has not yet resolved to NCI CTCAE v5.0 grade 0 or 1 prior to the first dose of study treatment; 4. The subjects with history of hypersensitivity to the study drug; 5. The subjects were not recovery after surgery with history of gastrointestinal perforation or fistula within 6 months prior to the enrollment; 6. The subjects with symptomatic central nervous system (CNS) metastasis or carcinomatous meningitis; 7. The subjects with pyloric obstruction; 8. The subjects with active or poorly controlled serious infections