An alternating regimen of irinotecan/ 5-fluorouracil/folinic acid and oxaliplatin/ 5-fluorouracil/folinic acid in metastatic colorectal cancer: a Phase II trial

OBJECTIVE: To assess the feasibility and activity of a combination schedule with irinotecan (CPT-11), oxaliplatin (L-OHP), brief infusional fluorouracil (5-FU) and folinic acid (FA) as first-line treatment in metastatic colorectal cancer (MCC) patients. METHODS: Fifty consecutive patients were treated with CPT-11 125 mg/m2 as a 90-min intravenous infusion, followed by FA 20 mg/m2 as an intravenous bolus, and 5-FU 500 mg/m2 over a 2-hour intravenous infusion on days 1 and 8. L-OHP was administered at 85 mg/m2 over 2 h on day 15, in combination with a FA 60 mg/m2 intravenous bolus and 5-FU 600 mg/m2 as a 2-hour intravenous infusion on days 15-16. The treatment was repeated every 4 weeks for a maximum of 9 cycles. RESULTS: Twenty-five of 50 assessable patients achieved a complete (n=5) or partial (n=20) response, leading to a response rate of 50% (95% CI 35-64%). Eighteen (36%) patients showed stable disease. The median time to tumor progression was 10.3 months (95% CI 9.6-10.9 months). After a median follow-up of 16.4 months, the median survival was not reached. Grade 3 neutropenia (8%), grade 3 nausea/vomiting (6%) and grade 3 diarrhea (2%) were the major adverse events. CONCLUSION: This alternating three-drug regimen is very well tolerated, manageable and effective in terms of activity and time to progression.