Daiichi Sankyo Company, Limited and ArQule Inc. announced the top-line results of a randomized Phase 2 signal generation trial of tivantinib (ARQ 197) used in combination with irinotecan and cetuximab in patients with refractory or relapsed colorectal cancer (CRC). Although the trial did not meet its primary endpoint of Progression-Free Survival (PFS), the analysis of the patients enrolled (n=122) showed that median PFS was 8.3 months in the experimental arm (patients treated with irinotecan and cetuximab plus tivantinib), compared with 7.3 months in the control arm (patients treated with irinotecan and cetuximab plus placebo) (hazard ratio = 0.85, 95% CI: 0.55, 1.33). Objective Response Rate (ORR), a secondary endpoint, was 45% in the experimental arm versus 33% in the control arm but was not statistically significant.

The PFS results obtained in both the control arm and the experimental arm were longer than expected compared to previously published historical norms. Additional data and analyses from this trial are planned for presentation at a future medical meeting and will include mature OS data as well as analyses of patient sub-groups, biomarker status and regional variability, including pre- and post study treatments.