FOLFOXIRI plus bevacizumab improves survival of patients with advanced colorectal cancer

This study compared the survival outcomes of different chemotherapy treatments in patients with inoperable advanced colorectal cancer (CRC). Researchers suggested that FOLFOXIRI plus bevacizumab (Avastin) significantly improved the survival of these patients.

Around 20% of patients present with advanced CRC at diagnosis. Chemotherapy is only of limited effectiveness in inoperable metastatic (spread to other parts of the body) CRC. Therefore, other types of therapies have been added to these treatments, such as targeted therapies. Bevacizumab is a targeted therapy that targets a protein called vascular endothelial growth factor (VEGF). This protein is involved in blood vessel growth in the tumor. By blocking this protein, bevacizumab prevents the growth of new blood vessels in the tumor that feed the tumor and stops its growth.

Standard chemotherapy for advanced CRC includes FOLFOX (fluorouracil, leucovorin, and oxaliplatin) or FOLFIRI (fluorouracil, leucovorin, and irinotecan). These 2 regimens are known as chemotherapy doublets. Recently, a regimen containing rinotecan, oxaliplatin, leucovorin, and fluorouracil (FOLFOXIRI) has been associated with improved outcomes in patients with advanced CRC. However, this regimen was also associated with more side effects.

FOLFOXIRI plus bevacizumab showed the best effect when compared with the other regimens. This combination therapy was then included among the recommended first-line treatment options for advanced CRC. However, studies so far lack information on the overall survival of patients receiving this treatment.

This study included information about 1697 patients with advanced CRC from 5 studies. Of these, 846 patients received FOLFOXIRI with bevacizumab (group 1), and 851 received FOLFOX/FOLFIRI with bevacizumab (group 2). The average follow-up period was 39.9 months. Overall survival (OS; time from treatment to death by any cause), progression-free survival (PFS; time from treatment to disease progression), response and resection rate were assessed. Side effects were also measured.

Patients from group 1 had significantly longer OS (28.9 months) than group 2 (24.5 months). These patients had a 19% improvement in the odds of better survival. Group 1 had a longer PFS (12.2 months) when compared to group 2 (9.9 months). These patients had a 26% improvement in the odds of a better PFS.

Group 1 also showed a higher response rate (64.5%) and resection rate (16.4%) when compared to group 2 who had a response rate of 53.6% and a resection rate of 11.8%.

Group 1 had a higher rate of side effects when compared to group 2. The most common severe side effects were neutropenia (45.8% vs 21.5%; decreased white blood cell counts) and diarrhea (17.8% vs 8.4%).

This study concluded that FOLFOXIRI plus bevacizumab improves the survival of patients with advanced CRC with a moderate increase in side effects.