When Avastin is added to the combination of Xeloda and irinotecan as an initial treatment for advanced colorectal cancer, the treatment is equally effective as Avastin with FOLFIRI.
But side effects are more difficult.
After a randomized clinical trial comparing Avastin with XELIRI (Xeloda, irinotecan) to Avastin with FOLFIRI (5-FU, leucovorin, irinotecan), researchers concluded that excessive side effects made using the XELIRI combination unwise.
Efficacy-wise there were no sigificant differences between the two regimens for:
- median progression-free survival(10.0 for FOLFIRI and 8.9 months for XELIRI)
- overall survival (25.7 and 27.5 months)
- response rates (45.5 and 39.8 percent)
However diarrhea, fever due to low white cell blood counts, and hand-foot syndrome were significantly more common in patients treated with XELIRI. They also had more treatment delays and dose reductions, and discontinued treatment because of side effects more often.
J Souglakos and his colleagues concluded,
The progression-free survival of FOLFIRI-Bevacizumab is not superior to that observed with the CAPIRI-Bev regimen. CAPIRI-Bev has a less favourable toxicity profile, requiring dose reductions, in order to be considered as an option in first-line treatment of patients with metastatic colorectal cancer.