XELIRI-bevacizumab versus FOLFIRI-bevacizumab as first-line treatment in patients with metastatic colorectal cancer: a Hellenic Cooperative Oncology Group phase III trial with collateral biomarker analysis

Abstract Background The aim was to compare two standard chemotherapy regimens combined with bevacizumab as first-line treatment in patients with metastatic colorectal cancer. Methods Patients previously untreated for metastatic disease were randomized in: group A (irinotecan, capecitabine, bevacizumab, every 3 weeks; XELIRI-bevacizumab) and group B (irinotecan, leucovorin, fluorouracil, bevacizumab, every 2 weeks; FOLFIRI-bevacizumab). Primary endpoint was progression-free survival (PFS). Plasma concentrations of nitric oxide, osteopontin, TGF-β1 and VEGF-A were measured at baseline and during treatment. Results Among 285 eligible patients, 143 were randomized to group A and 142 to group B. Fifty-five patients (38.5%) in group A and 57 (40.1%) in group B responded (p = 0.81). After a median follow-up of 42 months, median PFS was 10.2 and 10.8 months (p = 0.74), while median OS was 20.0 and 25.3 months (p = 0.099), for groups A and B, respectively. Most frequent grade 3–4 toxicities (group A vs group B) were neutropenia (13% vs 22%, p = 0.053) and diarrhea (19% vs 11%, p = 0.082). Baseline plasma osteopontin concentrations demonstrated prognostic significance for both PFS and OS. Conclusions This trial did not show significant differences in efficacy between the groups. However, the toxicity profile was different. Baseline plasma osteopontin concentrations demonstrated independent prognostic significance. (Registration number: ACTRN12610000270011)