XELOX Compares Favorably With FOLFOX4 in Adjuvant Therapy for Colorectal Cancer

ORLANDO-In first-line metastatic colorectal cancer, capecitabine(Drug information on capecitabine) (Xeloda) is better tolerated than fluorouracil(Drug information on fluorouracil)/ leucovorin (5-FU/LV), and the addition of capecitabine to oxaliplatin(Drug information on oxaliplatin) (Eloxatin)(XELOX) is both effective and tolerated, Hans-Joachim Schmoll, MD, PhD, said (abstract 3523). Dr. Schmoll reported early safety findings from a phase III trial of XELOX vs bolus 5-FU/LV as adjuvant therapy for patients with stage III colon cancer. "In the MOSAIC trial, oxaliplatin + 5-FU/LV (FOLFOX4) resulted in superior disease-free survival compared with 5-FU/LV and has recently been approved for adjuvant therapy. As in metastatic colorectal cancer, capecitabine should be considered as an alternative to 5-FU/LV in combination with oxaliplatin in the adjuvant setting. Therefore, we compared the safety and efficacy of XELOX with those of bolus 5-FU/LV (the standard regimen at the start of the study) as adjuvant therapy for stage III colon cancer," Dr. Schmoll said. This ongoing study enrolled 1,886 patients with resected stage III colon cancer. Patients were randomized to receive XELOX (capecitabine: 1,000 mg/m² twice daily on days 1-14 + oxaliplatin: 130 mg/m² on day 1, every 3 weeks for eight cycles) or IV bolus 5- FU/LV (Mayo Clinic regimen: LV-20 mg/m² + 5-FU-425 mg/m² on days 1- 5, every 4 weeks for six cycles; or Roswell Park regimen: LV-500 mg/m² + 5-FU-500 mg/m² on day 1, for weeks 1-6 in four 8-week cycles). Reduced Rate of Febrile Neutropenia A total of 1,719 patients were evaluable for safety. "There was a similar rate of related adverse events with XELOX and 5-FU/LV. There was less grade 3/4 stomatitis (1% vs 8%), neutropenia (8% vs 15%), and febrile neutropenia (< 1% vs 4%) with XELOX than with 5-FU/LV. There was more frequent grade 3 hand-foot syndrome (5% vs 1%) and grade 3/4 thrombocytopenia (5% vs 1%) with XELOX than with 5-FU/LV. Fifty-four percent of XELOX patients and 45% of 5-FU/LV patients experienced treatment-related grade 3/4 adverse events. Sixty-day all-cause mortality was 1% on both arms," Dr. Schmoll said. "The lower rate of neutropenia with XELOX led to a reduced rate of grade 3/4 febrile neutropenia," Dr. Schmoll said. Dr. Schmoll and investigators concluded that the safety data from this trial indicate that XELOX is feasible in adjuvant treatment of colon cancer and compares favorably with FOLFOX4. "XELOX appears to cause less myelosuppression and stomatitis but more skin and neurosensory toxicities than 5-FU/LV. XELOX has now been incorporated in the three-arm AVANT adjuvant trial (FOLFOX4 vs FOLFOX4 + bevacizumab [Avastin] vs XELOX + bevacizumab)," Dr. Schmoll said. Efficacy results are expected in 2007.