Phase IIT Trial of SNA014

Inclusion Criteria: * Age range of 18 to 75 years old (including boundary values); * Individuals with behavioral capacity who voluntarily participate in this clinical study and sign an informed consent form (ICF); * Diagnosed G/GEJ adenocarcinoma and pancreatic cancer; * Gastroscopy/CT/MRI/PET-CT examination results within the past month (if any); * Pathological test results and Claudin18.2 immunohistochemistry results within the past year (if available). Exclusion Criteria: * Merge patients with other clearly diagnosed malignant tumors: * Uncontrolled severe infections or individuals with other serious illnesses; * Those with an expected survival period of less than or equal to three months; * Pregnant or lactating patients, as well as reproductive age patients who refuse to take appropriate contraceptive measures during this trial; * investigators determine that patients who are not suitable to participate in this study;