4. Sep. 2017

GI tumor – New first-line treatment for mCRC

Several studies of S-1 and CPT-11 plus bevacizumab (Bmab) combination therapy have shown promising efficacy in patients with metastatic colorectal cancer (mCRC), suggesting the potential to replace mFOLFOX6 or CapeOX plus Bmab as first-line treatment.

The randomised, open-label, phase 3 TRICOLORE trial was performed to prove this concept. It aimed at determining whether S-1 and CPT-11 plus Bmab (group B) is non-inferior or superior to mFOLFOX6 or CapeOX plus Bmab (group A) in terms of progression-free survival (PFS). The non-inferiority margin was a hazard ratio (HR) of 1.25 based on the assumption of a median PFS of 11/12 months in group A/group B.

A total of 487 patients were enrolled and data were analyzed after confirming > 374 events as planned. All demographic factors were well balanced. Median PFS was 10.8 months in group A and 14.0 months in group B (HR 0.85, 95% CI: 0.70–1.03, p < 0.001 for non-inferiority, p = 0.087 for superiority). The RAS mutation status was evaluable in 67.6 %. In the RAS wild-type subgroup, median PFS was 11.6 months in group A and 15.9 months in group B. In the RAS mutant-type subgroup, median PFS was 9.3 months in group A and 11.3 months in group B.
In summary, S-1 and CPT-11 plus Bmab was non-inferior to mFOLFOX6 or CapeOX plus Bmab with respect to PFS and has now become a recommended first-line treatment for mCRC irrespective of RAS status.

Komatsu Y. et al., abstract 4740 : Treatment outcome according to tumor RAS mutation status in TRICOLORE trial: A randomized phase 3 trial of S-1 and irinotecan plus bevacizumab versus mFOLFOX6 or CapeOX plus bevacizumab as first-line treatment for metastatic colorectal cancer.