Phase II randomized trial on protracted 5-fluorouracil infusion plus oxaliplatin (FOX) versus capecitabine plus oxaliplatin (XELOX) as first-line treatment in advanced colorectal cancer (ACRC): Preliminary results of the Italian FOCA Study

Abstract

3617 Background: FOX regimen has shown to be safe and active in pretreated ACRC pts. Capecitabine (CAPE), an oral fluoropyrimidine, has been explored as an alternative to infusional 5-fluorouracil (5FU) in oxaliplatin (OXA) containing regimen (XELOX). The aim of this phase II randomized trial was to compare the efficacy and safety of FOX and XELOX as first line therapy in ACRC pts. Methods: From December 2001 to December 2004, 100 eligible untreated pts with ACRC have been randomized to arm A (FOX) (5-fluorouracil protracted infusion iv 250 mg/m2 d1–21 + oxaliplatin 130 mg/m2 iv d1, q3w) or arm B (XELOX) (capecitabine 1000 mg/m2 po bid d1–14, q3w + oxaliplatin 130 mg/m2 iv d1,q3w). Fourty-eight pts were randomized to arm A and 52 to arm B. Results: Baseline pt characteristics were well balanced between the two arms: M/F 52/48, median age 66.8 years (41–79); median KPS 90 (70–100); colon 71%, rectum 29%; primary tumor resection 80.9%; adjuvant chemotherapy 24%; metastatic sites: liver 77% (only liver 43%), lung 35%, lymph nodes 21%. Median number cycles was: 5 (1–10) in arm A and 6 (1–10) in arm B. Median dose intensity was: 5FU 100% (13–100) and OXA 100% (82–100) in arm A; CAPE 100% (16–100) and OXA 100% (60–100) in arm B. At the moment 75 pts were evaluable for response and 93 pts for toxicity. The objective responses were: arm A CR 3%, PR 48.5%, SD 27.3%, PD 21.2%; arm B CR 7.1%, PR 38.1%, SD 33.3%, PD 21.4%; RR 51.5% vs 45.2%. In arm A and B median TTP was 6 vs 9 months. Survival data are immature (58% of pts are still alive). Surgical resection of liver metastases after chemotherapy was performed in 4.1% pts in arm A vs 9.6% pts in arm B. Only 1 pt showed grade 4 toxicity (NCI-CTC2) (diarrhea) in arm A. Grade 3 treatment-related toxicity in arm A and B was: neutropenia 2.4% vs 0; thrombocytopenia 2.4% vs 2.4%; stomatitis 4.8% vs 0; diarrhea 14.3% vs 3.9%; hypertransaminasemia 0 vs 2%; hyperbilirubinemia 2.3% vs 2.1%; neurotoxicity 15.0% vs 20.4%. Conclusions: Our preliminary results suggest that FOX and XELOX, as administered in this trial, show high activity as first line treatment. Toxicity is low and similar in the two arms. No significant financial relationships to disclose.