San Francisco, CA—In routine patient care, adding bevacizumab (Avastin) to standard FOLFIRI (leucovorin, 5-fluorouracil, and irinotecan) improves progression-free survival (PFS) and overall survival (OS) in patients with metastatic colorectal cancer (mCRC), according to data presented at the 2014 Gastrointestinal Cancers Symposium.
“There is consistent benefit in terms of PFS and a more substantial advantage in terms of 1-, 2-, and 3-year survival rates with the addition of bevacizumab to FOLFIRI,” said lead investigator Jean A. Maroun, MD, Professor of Medicine, University of Ottawa, and Medical Oncologist, Ottawa Hospital Cancer Centre, Ontario, Canada.
Bevacizumab plus FOLFIRI has become the standard of care for the first-line treatment of mCRC, but few data exist about its utilization and effectiveness in the community. Dr Maroun and colleagues therefore looked at the outcomes of 470 patients with mCRC receiving standard first-line treatment with FOLFIRI alone or with FOLFIRI plus bevacizumab who were treated at the Ottawa Hospital Cancer Centre from January 2004 through August 2010.
A total of 176 (37%) patients received FOLFIRI plus bevacizumab, and 294 (63%) received FOLFIRI alone—127 before bevacizumab became available and 167 after. At the start of FOLFIRI therapy, the baseline characteristics were not significantly different between the 3 groups: the median age was 61 to 64 years, although a greater proportion of patients receiving bevacizumab were women compared with patients receiving FOLFIRI alone.
“Patients treated with FOLFIRI plus bevacizumab received more cycles of chemotherapy but with more dose adjustments,” said Dr Maroun. Patients receiving FOLFIRI plus bevacizumab completed 3579 cycles of chemotherapy, compared with 2404 cycles that were completed by the 167 patients who received FOLFIRI alone after bevacizumab was available, and 1606 cycles that were completed by the 127 patients who received FOLFIRI before bevacizumab became available.
Patients receiving FOLFIRI alone had a median of 16 cycles before bevacizumab became available and 13 cycles after. Patients receiving FOLFIRI plus bevacizumab had a median of 14 cycles of FOLFIRI and a median of 15 cycles of bevacizumab.
Overall, ?1 FOLFIRI dose adjustments were made in 78% of patients, with a median of 6 cycles to the first adjustment; 49% of patients had their first adjustment during the first 3 cycles. Bevacizumab was placed on hold in 95 (54%) patients: once in 35% of the patients, and twice in 25% of the patients. The median time off of bevacizumab was 37 days. The dose intensity across the 3 groups was approximately 76%.
Adverse events were responsible for at least 1 dose adjustment in 146 (83%) patients receiving FOLFIRI plus bevacizumab, and in 215 (73%) receiving FOLFIRI alone.
The median PFS was 17 months with FOLFIRI plus bevacizumab. In patients receiving FOLFIRI before bevacizumab availability, the median PFS was 13 months, and in those receiving it after the availability of bevacizumab, it was 14 months.
Over 3 years, OS rates in the 3 groups (FOLFIRI plus bevacizumab, FOLFIRI alone before bevacizumab availability, and FOLFIRI alone after the availability of bevacizumab) were 90%, 77%, and 78%, respectively, at 1 year; 67%, 49%, and 56%, respectively, at 2 years; and 54%, 31%, and 44%, respectively, at 3 years. At the time of data cutoff, there was an insufficient number of events to estimate median OS, said Dr Maroun.
