Study on Cadonilimab and Chemotherapy for Gastric or Gastroesophageal Junction Cancer

Inclusion Criteria

• Able to provide signed consent to participate.
• Aged 18 years or older.
• In good general health, with a performance status of 0 or 1, meaning fully active or restricted in physically strenuous activity but ambulatory.
• Diagnosed with a specific type of gastric or gastroesophageal junction cancer that can be surgically removed.
• Tumor must be HER2-negative.
• Have adequate organ and bone marrow function, including:
  • Hemoglobin level of at least 9.0 g/dL.
  • Neutrophil count of at least 1.5 x 10^9/L.
  • Platelet count of at least 100 x 10^9/L.
  • Normal liver function tests, with some exceptions for known conditions like Gilbert's disease.
  • Kidney function with creatinine clearance over 50 mL/min.
• Willing to undergo tumor biopsies before and during treatment.
• Women of childbearing potential must have a negative pregnancy test and agree to use effective contraception during and after the study.
• Men with partners of childbearing potential must agree to use effective contraception during and after the study.

Exclusion Criteria

• Have a type of cancer other than adenocarcinoma, such as squamous cell carcinoma or neuroendocrine tumors.
• Tumor is HER2-positive.
• Have received any prior treatment for the cancer being studied.
• Have previously received certain types of immunotherapy.
• Have medical conditions that make the study treatment unsafe, such as:
  • Lung disease or history of lung inflammation.
  • Active infections requiring treatment.
  • Significant heart disease or recent heart attack.
  • History of organ transplant.
• Require high doses of steroids or other immune-suppressing medications.
• Have active autoimmune diseases requiring treatment in the past two years, except for certain conditions like stable hypothyroidism.
• Have allergies to any components of the study drugs.
• Have had another active cancer in the past two years, except for certain skin cancers or other localized cancers that have been treated.
• Have HIV with a detectable viral load, unless on effective treatment.
• Have active hepatitis B or C infections, unless on effective treatment with undetectable viral load.
• Have received a live vaccine within 30 days before starting the study treatment.