This study is a randomized, open, multicenter phase III clinical study designed to compare the efficacy and safety of QLS31905 injection combined with CAPOX versus sintilimab combined with CAPOX in the first-line treatment of CLDN18.2 positive, PD-L1 CPS \< 5 unresectable locally advanced or metastatic gastric or gastroesophageal junction adenocarcinoma.
Subjects voluntarily participate in the study and sign the informed consent form;
Eastern Cooperative Oncology Group (ECOG) performance status score of 0-1;
Expected survival time ≥ 12 weeks;
Histologically or cytologically confirmed diagnosis of gastric or gastroesophageal junction adenocarcinoma;
Known history of allergy to any component of the study drug;
Other second primary malignant neoplasm within 5 years;
Significant cardiovascular and cerebrovascular disorders within 6 months before randomization;
Haemorrhage requiring haemostatic treatment within 3 months prior to randomisation;