Oxaliplatin is a chemotherapy medicine that is given through an IV. It works by damaging the DNA of cancer cells, which helps stop their growth. In this study it is used as a standard‑of‑care comparison treatment.

Mycophenolate mofetil is a medicine that suppresses the immune system. It is taken as a capsule by mouth. In the trial it is part of the background therapy to help control the body’s immune response.

AZD0901 is an experimental drug that is given by IV. It is being tested in the trial to see if it can improve outcomes for patients with advanced gastric or esophageal cancer.

Infliximab is a biologic medication given as an IV infusion. It blocks a protein called TNF‑alpha that can cause inflammation. In this study it is included as part of the background treatment regimen.

Nivolumab is an immunotherapy drug that helps the body’s own immune cells recognize and attack cancer. It is administered by IV and is being evaluated as a potential new treatment option in the trial.

Folinic acid is a form of vitamin B9 given by IV. It is used to protect normal cells from the side effects of certain chemotherapy drugs. In this study it is used alongside other chemotherapy as a comparator.

Zolbetuximab is a monoclonal antibody that targets a protein called Claudin‑18.2 on cancer cells. It is given by IV infusion and serves as a comparator treatment in the trial.

Rilvegostomig is an investigational medication delivered by IV infusion. It is being tested both alone and in combination with other drugs to see if it can improve cancer control.

Capecitabine is an oral chemotherapy pill that the body changes into the active drug fluorouracil. It interferes with cancer cell DNA and is a key part of the experimental treatment regimen.

Fluorouracil is a chemotherapy drug given by IV infusion. It stops cancer cells from making DNA, slowing their growth. In this trial it is used as part of the standard‑of‑care comparison.

Sonesitatug vedotin is an antibody‑drug conjugate designed to target the Claudin‑18.2 protein on tumor cells. It delivers a cell‑killing agent directly to the cancer while sparing normal tissue. The study is testing this drug together with capecitabine, with or without rilvegostomig, to see if it works better than current standard treatments.

Gastric cancer – A cancer that starts in the lining of the stomach. It often begins as small abnormal cells that grow slowly, then become larger and invade deeper layers of the stomach wall. Over time it can spread to nearby lymph nodes and other organs.
Gastroesophageal junction adenocarcinoma – A cancer that forms at the point where the esophagus joins the stomach. It originates in gland‑like cells at this junction and can grow upward into the esophagus or downward into the stomach. The tumor may extend into surrounding tissues and lymph nodes as it progresses.
Esophageal cancer expressing Claudin‑18.2 – A type of esophageal cancer that carries the protein Claudin‑18.2 on its surface. The disease starts in the lining of the esophagus, grows deeper into the wall, and can spread locally and to distant sites. The Claudin‑18.2 expression is a distinct characteristic of the tumor cells.