Optimal Duration of Oxaliplatin in Adjuvant XELOX for Gastric Cancer Patients (EXODOX)

Prior treatment

• Sexually active men and women who are not willing to implement contraception during study and until 3 months after discontinuation of study drug
• Prior systemic chemotherapy or radiation therapy for stomach cancer
• Received any investigational drug or procedure within 4 weeks prior to randomization

Other illness

• Evidence of metastasis (including cytologically confirmed malignant ascites)
• History of other malignancies within the last 3 years (excluding adequately treated basal cell carcinoma of the skin, in situ cancer of the cervix, non-metastatic thyroid cancer)
• A history of clinically significant uncontrolled seizures, central nervous system disorders, or mental disorders, which make it impossible to understand the informed consent or interfere with compliance with oral drug intake
• Clinically significant (i.e., active) heart disease: e.g. unstable angina requiring medication, symptomatic coronary artery disease, congestive heart failure with NYHA grade II or higher, severe cardiac arrhythmias or acute coronary syndrome in the past 6 months (including myocardial infarction)
• Lack of integrity or malabsorption syndrome in the upper gastrointestinal tract, which is likely to affect the absorption of study drug
• Serious uncontrolled infection or other serious uncontrolled disease
• History of allograft requiring immunosuppression therapy
• Active viral infection (for hepatitis B carrier, patients can be registered if HBV-DNA titer is less than 20,000 IU/mL, and are allowed to use prophylactic antiviral agents by investigator's choice)
• Active HIV infection
• Patients with peripheral sensory neuropathy with functional impairment

Other

• Female patients who are pregnant or breast-feeding
• Positive pregnancy test at baseline (postmenopausal women should be amenorrhea for at least 12 months to be considered non-fertile)
• Patients who have not recovered from serious complications of gastrectomy

• Histologically or cytologically confirmed gastric or gastroesophageal junction adenocarcinoma patients who underwent curative surgery (D1 beta or D2 resection)
• Pathologically confirmed stage II, III patients (AJCC 8th edition)
• Age 19 years and older
• Eastern Cooperative Oncology Group (ECOG) performance status 0 or 2
• Adequate marrow function (ANC \> 1,500/uL, Platelet \>100,000/uL, Hb \> 8.0 g/dL, patients with chronic anemia who require intermittent blood transfusions can also participate in the study)
• Adequate renal function, with serum creatinine \< 1.5 x upper limit of normal (ULN).
• Adequate hepatic function with serum total bilirubin ≤ 1.5 x ULN, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤ 3 x ULN
• Written, informed consent to the study