Adjuvant capecitabine plus oxaliplatin after D2 gastrectomy in Japanese patients with gastric cancer: a phase II study

BACKGROUND: Adjuvant chemotherapy with XELOX (capecitabine plus oxaliplatin) has been shown to be beneficial following resection of gastric cancer in South Korean, Chinese, and Taiwanese patients. This phase II study (J-CLASSIC-PII) was undertaken to evaluate the feasibility of XELOX in Japanese patients with resected gastric cancer. METHODS: Patients with stage II or III gastric cancer who underwent curative D2 gastrectomy received adjuvant XELOX (eight 3-week cycles of oral capecitabine, 1000 mg/m(2) twice daily on days 1–14, plus intravenous oxaliplatin 130 mg/m(2) on day 1). The primary endpoint was dose intensity. Secondary endpoints were safety, proportion of patients completing treatment, and 1-year disease-free survival (DFS) rate. RESULTS: One hundred patients were enrolled, 76 of whom completed the study as planned. The mean dose intensity was 67.2 % (95 % CI, 61.9–72.5 %) for capecitabine and 73.4 % (95 % CI, 68.4–78.4 %) for oxaliplatin, which were higher than the predefined age-adjusted threshold values of 63.4 % and 69.4 %, respectively, and the study therefore met its primary endpoint. The 1-year DFS rate was 86 % (95 % CI, 77–91 %). No new safety signals were identified. CONCLUSIONS: The feasibility of adjuvant XELOX in Japanese patients with resected gastric cancer is similar to that observed in South Korean, Chinese, and Taiwanese patients in the Capecitabine and Oxaliplatin Adjuvant Study in Stomach Cancer (CLASSIC) study. Based on findings from this study and the CLASSIC study, the XELOX regimen can be considered an adjuvant treatment option for Japanese gastric cancer patients who have undergone curative resection. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s10120-016-0606-4) contains supplementary material, which is available to authorized users.