Background: Capecitabine in combination with oxaliplatin and irinotecan (COI regimen) is active and well tolerated in metastatic colorectal cancer. Since there is no internationally adopted standard regimen, we have conducted a pilot study of COI in untreated advanced gastric cancer.
Methods: Patients received irinotecan, 180 mg/m2 infused over 90 min on day 1, followed by oxaliplatin, 85 mg/m2 in a 3-hr infusion on day 2, and capecitabine, 1000 mg/m2/day orally twice daily from days 2 to 6 of a biweekly schedule. Treatment was continued up to 8 cycles or until progression of disease occurred. Response (RECIST criteria) was assessed after the first three cycles and was to be confirmed at least 4 weeks following the first response.
Results: A total of 12 patients (5 men and 7 women) with a median age of 54 years (range, 42-65) was prospectively enrolled. Most of the patients (83%) had metastatic disease. Three complete responses, four partial responses and two disease stabilizations occurred in the intention-to-treat cohort, with an overall response rate of 58% (95% confidence interval, 28-85%). Median time to progressive disease and overall survival were 6.4 and 12 months, respectively. A total of 68 cycles was administered, with a median of 6 cycles per patient (range, 1-8). Grade 3 neutropenia occurred in two patients. The most common non-hematologic grade 3 toxicities were nausea (3 patients) and diarrhea 12 patients).
Conclusions: These preliminary findings suggest that biweekly COI is a feasible and promising triplet for the first-line treatment of advanced gastric cancer. A large multi-institutional phase II study of the combination has already been planned in this setting.