Inclusion Criteria:  Provide signed informed consent; Male or female aged at 18-75 (inclusive) years; Expected survival ≥12 weeks; ECOG PS score 0 or 1; Provide archival or fresh tissues for CLDN18.2 expression analysis; Adequate laboratory parameters; 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:  The subjects who received the treatment with CLDN18.2 monoclonal antibody or CLDN-18.2 CART; The subjects who received other anti-tumor medication within 4 weeks prior to the initial dose of the study drug; 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; The subjects with history of hypersensitivity to the study drug; The subjects were not recovery after surgery with history of gastrointestinal perforation or fistula within 6 months prior to the enrollment; The subjects with symptomatic central nervous system (CNS) metastasis or carcinomatous meningitis; The subjects with pyloric obstruction; The subjects with active or poorly controlled serious infections