Oxaliplatin plus high-dose folinic acid and 5-fluorouracil i.v. bolus (OXAFAFU) versus irinotecan plus high-dose folinic acid and 5-fluorouracil i.v. bolus (IRIFAFU) in patients with metastatic colorectal carcinoma: a Southern Italy Cooperative Oncology Group phase III trial

Purpose: The primary end point of this phase III trial was to compare the response rate (RR) of oxaliplatin (OXA) plus levo-folinic acid (l-FA) and 5-fluorouracil (5-FU) bolus with that of irinotecan (IRI) plus l-FA and 5-FU bolus in advanced colorectal carcinoma. Patients and methods: Patients with measurable metastatic colorectal carcinoma were randomly allocated to receive: IRI 200 mg/m(2) on day 1, l-FA 250 mg/m(2) intravenously plus 5-FU 850mg/m(2) on day 2 (IRIFAFU); or OXA 100 mg/m(2) on day 1, I-FA 250 mg/m(2) plus 5-FU 1050mg/m(2) on day 2 [OXAFAFU high dose (hd)]. Cycles were given every 2 weeks. After a planned interim analysis, OXA was reduced to 85 mg/m(2) and 5-FU to 850 mg/m(2) [OXAFAFU low dose (ld)]. Results: Two hundred and seventy-four patients (IRIFAFU, 135; OXAFAFUhd, 71; OXAFAFUld, 68) were treated. Forty-two confirmed responses were achieved with IRIFAFU, 29 with OXAFAFUhd and 32 with OXAFAFUld. The response rate with OXAFAFU [44%; 95% confidence interval (CI) 35% to 52%] was significantly higher (P = 0.029) than that of IRIFAFU (31%; 95% CI 23% to 40%). Occurrence of grade 3 neutropenia with OXAFAFUld was similar to that for IRIFAFU (29% versus 31%), while severe diarrhoea was significantly lower (12% versus 24%). Median failure-free survival (7 versus 5.8 months; P = 0.046) and overall survival of patients (18.9 versus 15.6 months; P = 0.032) were significantly prolonged with OXAFAFU. Conclusions: OXAFAFU was more active and less toxic than IRIFAFU, and it should be preferred in the first-line treatment of advanced colorectal cancer patients.