Background: The study aimed to demonstrate the noninferiority of capecitabine to 5-fluorouracil (5-FU)/folinic acid (FA), in relation to progression-free survival (PFS) after first-line treatment of metastatic colorectal cancer and the benefit of adding celecoxib (C) to irinotecan/fluoropyrimidine regimens compared with placebo (P).
Patients and methods: Patients were randomly assigned to receive FOLFIRI: irinotecan (180 mg/m(2) i.v. on days 1, 15 and 22); FA (200 mg/m(2) i.v. on days 1, 2, 15, 16, 29 and 30); 5-FU (400 mg/m(2) i.v. bolus, then 22-h, 600 mg/m(2) infusion) or CAPIRI: irinotecan (250 mg/m(2) i.v. infusion on days 1 and 22); capecitabine p.o. (1000 mg/m(2) b.i.d. on days 1-15 and 22-36). Patients were additionally randomly assigned to receive either placebo or celecoxib (800 mg: 2 x 200 mg b.i.d.).
Results: The trial was closed following eight deaths unrelated to disease progression in the 85 enrolled (629 planned) patients. Response rates were 22% for CAPIRI + C, 48% for CAPIRI + P, 32% for FOLFIRI + C and 46% for FOLFIRI + P. Median PFS and overall survival (OS) times were shorter for CAPIRI versus FOLFIRI (PFS 5.9 versus 9.6 months and OS 14.8 versus 19.9 months) and celecoxib versus placebo (PFS 6.9 versus 7.8 months and OS 18.3 versus 19.9 months).
Conclusion: Due to the small sample size following early termination, no definitive conclusions can be drawn in relation to the noninferiority of CAPIRI compared with FOLFIRI.