By Megan Brooks

NEW YORK (Reuters Health) - Patients with advanced colorectal cancer fare better with first-line treatment with FOLFOXIRI (folinic acid, 5-FU, oxaliplatin and irinotecan) plus bevacizumab than with FOLFIRI (folinic acid, 5-FU and irinotecan) plus bevacizumab, according to updated survival results from the Italian TRIBE study.

The FOLFOXIRI regimen extended overall survival by about four months and doubled the estimated five-year overall survival rate, Dr. Chiara Cremolini, medical oncologist at the Tuscan Tumor Institute in Pisa, Italy, reported January 12 during a media briefing, ahead of the 2015 Gastrointestinal Cancers Symposium, which opens January 15 in San Francisco.

For patients who are otherwise in good health, FOLFOXIRI plus bevacizumab represents a "valuable option" for the upfront treatment of metastatic colorectal cancer, Dr. Cremolini said.

In the phase 3 TRIBE study, 508 patients with metastatic colorectal cancer were randomly allocated to a maximum 12 cycles of induction therapy with FOLFIRI + bev or FOLFOXIRI + bev, followed by maintenance treatment with bevacizumab plus 5-FU until disease progression.

After a median of 48.1 months, 374 patients had died (200 of 256 in the FOLFIRI group vs 174 of 252 in the FOLFOXIRI group).


Median overall survival was significantly better in the FOLFOXIRI arm than the FOLFIRI arm (29.8 vs 25.8 months, hazard ratio 0.80, p=0.030), Dr. Cremolini reported.

The three- and four-year overall survival rates were 40.0% and 27.3%, respectively, with FOLFOXIRI + bev, versus 34.5% and 22.9%, respectively, with FOLFIRI + bev.

FOLFOXIRI + bev doubled the estimated five-year overall survival rate as compared to FOLFIRI + bev (24.9% vs 12.5%), Dr. Cremolini reported.

Briefing moderator Dr. Smitha Krishnamurthi, of the American Society of Clinical Oncology (ASCO) symposium news planning team and Case Western Reserve University in Cleveland, Ohio, noted that for patients who can tolerate combining three chemotherapy drugs, the FOLFOXIRI + bev regimen is an "important treatment advance."

Dr. Cremolini emphasized that this more intensive regimen is not for everyone. FOLFOXIRI increased the incidence of grade 3/4 diarrhea, mucositis, neuropathy and neutropenia, compared to FOLFIRI, but not serious adverse events. Many patients are able to tolerate FOLFOXIRI, but it is an intensive regimen and should not be given to all patients, such as those over age 75 and those between 70 and 75 who are not in good general condition, she said.

The 2015 Gastrointestinal Cancers Symposium is co-sponsored by ASCO, the American Gastroenterological Association Institute, the American Society for Radiation Oncology and the Society for Surgical Oncology.

The study was supported by the Gruppo Oncologico Nord Ovest (GONO) and the ARCO Foundation and a research grant from F. Hoffmann-La Roche. In their abstract, the authors have disclosed financial relationships with several pharmaceutical companies.