This clinical trial is focused on studying a type of cancer known as locally advanced or metastatic MSI/dMMR esogastric adenocarcinoma. This is a form of stomach cancer that has specific genetic characteristics, making it more challenging to treat. The study aims to compare the effectiveness of a new combination of treatments against the current standard treatment. The new treatment involves two drugs called botensilimab and balstilimab, which are types of immune checkpoint inhibitors. These drugs work by helping the immune system recognize and attack cancer cells. The standard treatment being compared includes a combination of chemotherapy drugs known as FOLFOX or XELOX, along with another immune therapy drug called nivolumab.

The purpose of this study is to see which treatment option helps patients live longer. Participants in the study will be randomly assigned to receive either the new combination of botensilimab and balstilimab or the standard treatment with FOLFOX/XELOX and nivolumab. The study will last for a period of up to 24 months, during which patients will receive their assigned treatment and be monitored regularly. The treatments are given through an IV infusion, which means they are administered directly into the bloodstream through a vein. Some patients may also receive a placebo, which is a substance with no active drug, to help compare the effects of the treatments more accurately.

Throughout the study, doctors will closely monitor the patients’ health and any side effects they may experience. The main goal is to determine which treatment is more effective in improving the overall survival of patients with this type of cancer. The study will also look at other factors, such as the quality of life of the patients and how their cancer responds to the treatment over time. This research is important for finding better ways to treat this challenging form of cancer and potentially improving outcomes for patients in the future.