Cadonilimab Combination Regimen as First-line Treatment for HER2-expressing GC/GEJ Patients

Cohort 1:10 mg/kg, iv, Q3W, D1; Cohort 2/3:6 mg/kg, iv, Q2W, D1

loading dose 8 mg/kg, iv, Q3W, D1; maintenance dose 6 mg/kg, iv, Q3W, D1

Oxaliplatin: 130 mg/m\\(\^2\\), IV, D1; Capecitabine: 1000 mg/m\\(\^2\\), oral (PO), twice daily, D1-14.

1.5、2.0、2.5mg/kg，IV，D1，Q2W

Oxaliplatin 85 mg/m\\(\^2\\), IV, d1; Leucovorin (folinic acid) 400 mg/m\\(\^2\\), IV, d1; 5-FU 400 mg/m\\(\^2\\), IV, d1, followed by 2400 mg/m\\(\^2\\), continuous intravenous infusion over 46 hours.