investigators reported in the .
In analyzing data from five clinical trials, the investigators found a 4.4-month increase in median overall survival and an 11.6% increase in estimated 5-year overall survival with FOLFOXIRI versus doublets. The trade-off was a higher incidence of grade 3-4 adverse events with FOLFOXIRI.
FOLFOXIRI plus bevacizumab is already included among first-line options in most clinical guidelines and recommendations, but there was no “proper estimation of the magnitude of the overall survival benefit” because trials had other primary endpoints, according to study author Chiara Cremolini, MD, PhD, of University of Pisa (Italy), and colleagues.
“To fully appreciate the cost/benefit balance of this option,” the investigators wanted to see how the numbers played out when overall survival was the primary endpoint, so they pooled individual patient data from the
Patient characteristics and treatment
The analysis included 1,697 patients. The median age was 61 years (range, 53-67 years).
About 99% of patients had an Eastern Cooperative Oncology Group performance score of 0 or 1. About 20% had left-sided RAS and BRAF wild-type tumors because of the increased use of anti–epidermal growth factor receptor antibodies as first-line therapy for that indication in recent years.
In all, 846 patients were randomized to FOLFOXIRI plus bevacizumab and 851 to bevacizumab with doublets: 69.9% to FOLFOX (leucovorin, fluorouracil, and oxaliplatin) and 30.1% to FOLFIRI (fluorouracil, leucovorin, and irinotecan).
The duration of induction in all five trials ranged from 4 to 6 months. It was followed by maintenance with a fluoropyrimidine (fluorouracil and leucovorin or capecitabine) plus bevacizumab.
Efficacy and safety
At a median follow-up of 39.9 months, the median overall survival was 28.9 months in the FOLFOXIRI group and 24.5 months in the doublet group (P < .001). The estimated 5-year overall survival rate was 22.3% and 10.7%, respectively.
The median progression-free survival was 12.2 months in the FOLFOXIRI group and 9.9 months in the doublet group (P < .001).
The objective response rate was higher with FOLFOXIRI (64.5% vs. 53.6%, P < .001), as was R0 resection rate (16.4% vs. 11.8%, P = .007).
The FOLFOXIRI group also had a higher incidence of grade 3-4 adverse events, including neutropenia (45.8% vs. 21.5%; P < .001), febrile neutropenia (6.3% vs. 3.7%; P = .019), nausea (5.5% vs. 3.0%; P = .016), mucositis (5.1% vs. 2.9%; P = .024), and diarrhea (17.8% vs. 8.4%; P < .001).
Even so, FOLFOXIRI plus bevacizumab was not associated with a significant increase in toxic deaths (2.3% vs. 1.4%; P = .277).
Patient selection is ‘critical’
Based on their findings, the investigators said the best candidates for first-line FOLFOXIRI plus bevacizumab may be younger patients with an ECOG performance status of 0 or 1 and right-sided and/or RAS-mutated tumors not exposed to a previous oxaliplatin-based adjuvant regimen.
FOLFOXIRI plus bevacizumab did not provide any additional benefit in patients with BRAF-mutant tumors, so the combination shouldn’t be the first choice in this group, the investigators wrote. “FOLFOX plus bevacizumab seems the preferable upfront option.”
For left-sided RAS and BRAF wild-type tumors, a chemotherapy doublet with an anti–epidermal growth factor receptor remains the preferred option, according to the investigators.
“The study does support the use of FOLFOXIRI and bevacizumab as a valuable first-line option, but patient selection is critical because there is a toxicity cost; this efficacy versus toxicity will constantly be a seesaw for us,” commentedof Massachusetts General Hospital in Boston, when the study was presented at the American Society of Clinical Oncology annual meeting earlier this year.
There was no external funding for this analysis. Three of the original five trials were sponsored by Roche. The study authors had numerous industry ties. Among others, Dr. Cremolini is a consultant for and reported honoraria and travel expenses from Roche. One author was a Genentech employee. Dr. Parikh disclosed relationships with Lilly, Genentech, and other companies.
SOURCE: Cremolini C et al. J Clin Oncol. 2020 Aug 20.