Randomized phase II study of FOLFIRI plus ramucirumab versus FOLFOXIRI plus ramucirumab as first-line treatment for metastatic colorectal cancer: WJOG9216G (RECAST)

Abstract

Background: FOLFOXIRI plus bevacizumab improved efficacies and increased some adverse events in untreated metastatic colorectal cancer (mCRC), compared with the doublet plus bevacizumab. The clinical outcomes of ramucirumab (RAM) in combination with FOLFIRI or FOLFOXIRI as a first-line treatment are unknown. In this randomized phase II study (WJOG9216G), we compared the efficacy and safety of these regimens to determine which is more promising.

Methods: Patients with untreated mCRC were randomly assigned to the FOLFIRI-RAM or FOLFOXIRI-RAM arms. The primary endpoint was a confirmed objective response rate (ORR), and secondary endpoints included early tumor shrinkage (ETS), progression-free survival (PFS), overall survival (OS), and safety.

Results: In total, 122 patients were randomized. The confirmed ORR was 59.3% and 60.3% in the FOLFIRI-RAM and FOLFOXIRI-RAM arms, respectively (odds ratio 1.04; P = 0.91). With a median follow-up period of 42.1 and 40.4 months, PFS was comparable between the FOLFIRI-RAM and FOLFOXIRI-RAM arms (median, 11.5 and 10.5 months). ETS rate (71.2% and 52.4%) and OS (median, 32.6 and 28.2 months) were significantly better in the FOLFIRI-RAM arm than in the FOLFOXIRI-RAM arm. The major grade ≥ 3 adverse events in the FOLFIRI-RAM and FOLFOXIRI-RAM arms were neutropenia (44.1% and 72.6%), anorexia (3.4% and 14.5%), and febrile neutropenia (3.4% and 11.3%).

Conclusions: FOLFOXIRI plus RAM was not superior to FOLFIRI plus RAM in terms of efficacy, including ORR, in patients with untreated mCRC. Instead, first-line FOLFIRI plus RAM showed clinical efficacy and safety profiles comparable to those of doublet chemotherapy plus bevacizumab.

Keywords: FOLFIRI; FOLFOXIRI; Metastatic colorectal cancer; RCT; Ramucirumab.