Addition of oxaliplatin to FOLFIRI and bevacizumab doubled 5-year survival.

Twice as many patients with metastatic colorectal cancer remained alive after 5 years with a four-drug chemotherapy regimen plus bevacizumab (Avastin) versus three drugs and the angiogenesis inhibitor, investigators reported here.

The 5-year overall survival was 24.9% with leucovorin, fluorouracil (5-FU), irinotecan, oxaliplatin (FOLFOXIRI), and bevacizumab and 12.4% with leucovorin-fluorouracil-irinotecan (FOLFIRI)-bevacizumab. After a median follow-up of 4 years, overall survival was 29.8 months with FOLFOXIRI and 25.8 months with FOLFIRI.

Median progression-free survival (PFS) increased from 9.7 months with FOLFIRI to 12.3 months with the four-drug chemotherapy regimen, Chiara Cremolini, MD, of Tuscan Tumor Institute of in Pisa, Italy, reported at the GI ASCO Cancer meeting.
“FOLFOXIRI plus bevacizumab doubles the estimated 5-year overall survival rate as compared to FOLFIRI plus bevacizumab,” Cremolini said during a press briefing that preceded the symposium. “FOLFOXIRI plus bevacizumab represents a valuable option for the upfront treatment of metastatic colorectal cancer.”

The more intense regimen was associated with increased toxicity, which was manageable, she added. However, the regimen would not be suitable for patients older than 75 or those who are 70 to 75 and not in good health. The trial excluded patients who were 75 or older.

The results reflect the ongoing efforts to extend the survival gains achieved in metastatic colorectal cancer over the past decade. Though the disease still has a poor prognosis, survival has improved significantly with the advent of modern combination chemotherapy and the introduction of targeted therapy, such as bevacizumab.
The two most widely used first-line chemotherapy regimens for metastatic colorectal cancer are FOLFIRI and FOLFOX (leucovorin-fluorouracil-oxaliplatin). Giving bevacizumab in addition to the chemotherapy has been shown to improve survival compared with chemotherapy alone.