North American (NA) subgroup results from VELOUR: Ziv-aflibercept versus placebo (pbo) plus FOLFIRI in mCRC that is resistant to or has progressed after an oxaliplatin-containing regimen

465 Background: Ziv-aflibercept (trade name ZALTRAP; known outside the US as aflibercept) is a new multiple angiogenic inhibitor that prevents VEGF-A, VEGF-B and PLGF from binding their receptors. Ziv-aflibercept was recently approved by the FDA in combination with FOLFIRI for patients with mCRC that is resistant to or has progressed after an oxaliplatin-containing regimen. Approval was based on the multinational phase III VELOUR trial (N=1226) which showed statistically significant improvements in overall survival (OS), progression-free survival (PFS), and overall response rate (ORR) with aflibercept + FOLFIRI. Detailed analyses of the NA subgroup are presented here. Methods: Patients were randomized 1:1 to ziv-aflibercept (4 mg/kg) + FOLFIRI or pbo + FOLFIRI every 2 wk. Patients had ECOG performance status (PS) ≤2, 1 prior oxaliplatin-based regimen, and prior bevacizumab (bev) was allowed. Primary endpoint was OS. The NA analysis was pre-specified, but not powered, to compare within or between subgroups. Results: NA patients (N=138) were randomized to ziv-aflibercept + FOLFIRI (n=63) or pbo + FOLFIRI (n=75). Baseline characteristics were similar in both arms (ziv-aflibercept: median 61 yrs; 60% male; 96% PS 0-1; 56% >1 metastatic organ; 74% prior bev). Ziv-aflibercept vs pbo improved median OS (17.94 vs 12.88 mos; HR=0.691, 95% CI: 0.442-1.079), median PFS (6.01 vs 4.17 mos; HR=0.536, 99.9% CI: 0.222-1.296) and ORR (12% vs 9%). Patients on average received more cycles (median 8.5 vs 7.0) and had longer duration of exposure (median 20 vs 14 wk), but had more treatment modifications with ziv-aflibercept vs pbo. Most of the severe AEs (grade ≥3) with ziv-aflibercept were grade 3 including hypertension, venous thromboembolic events, proteinuria, diarrhea, fatigue/asthenia, infection, stomatitis/ulceration and neutropenia. There were few grade 4 AEs. Conclusions: Ziv-aflibercept + FOLFIRI in NA mCRC patients previously treated with an oxaliplatin-based regimen (with or without prior bev) resulted in improved OS, PFS, and ORR, with an acceptable safety profile. The NA results are consistent with the VELOUR worldwide population. Clinical trial information: NCT00561470.