Can capecitabine replace 5-FU/leucovorin in combination with oxaliplatin for the treatment of advanced colorectal cancer?

The combination of capecitabine (Xeloda) and oxaliplatin (Eloxatin), or XELOX, is an effective and safe approach to the treatment of advanced colorectal cancer, with the potential advantage of convenience over standard combination regimens. In a large multicenter phase II trial for patients with metastatic colorectal cancer (N = 96), first-line treatment with oral capecitabine at 1,000 mg/m2 twice daily for 14 days and oxaliplatin at 130 mg/m2 by 2-hour infusion on day 1 every 21 days produced objective response in 55% of patients and stable disease (greater than 3 months) in a further 32%. Preliminary data indicate a median progression-free survival of 7.6 months (with 14% of patients still having not progressed) and median survival of over 16 months (with 59% of patients still alive); the 1-year survival rate was 72%. Grade 3 or 4 toxicity was relatively infrequent; in particular, grade 3 hand-foot syndrome occurred in just 3% of patients and severe neutropenia in only 6%. Treatment delivery was highly successful, with a median of 10 cycles being administered (range: 1-23 cycles). Both efficacy and safety outcomes with the XELOX combination compare well with those observed with infusional fluorouracil (5-FU)/leucovorin plus oxaliplatin (FOLFOX4) in first-line treatment for advanced disease. However, 3-weekly XELOX requires less time in hospital and is simpler than the 2-weekly standard FOLFOX4 regimen. Phase III trials comparing XELOX with infusional 5-FU/leucovorin/oxaliplatin are ongoing.