Comparison of PFS and safety for Asian compared to North American and European populations in the phase III trial of pazopanib versus sunitinib in patients with treatment-naive RCC (COMPARZ).

366 Background: Pazopanib (P) and sunitinib (S) are multi-kinase angiogenesis inhibitors that positively impact progression-free survival (PFS) in patients (pts) with metastatic renal cell carcinoma (mRCC) (NEJM 2007 356:115; JCO 2009 29:475). The safety profile of multi-kinase angiogenesis inhibitors has been shown to vary depending upon ethnic background (Oncology 2011 80:395). Methods: Treatment naive pts with clear cell mRCC and measurable disease were randomized 1:1 to P, 800mg QD continuous dosing or S, 50 mg QD for 4 weeks followed by 2 weeks off treatment. Primary endpoint was PFS. A subgroup analysis compared PFS (Cox analysis with treatment as only covariate) and AEs between the Asian, North American (NA), and European (EU) populations. Of the 1,110 pts 367 were from Asia (188 P, 179 S). Results: PFS in the Asian subgroup was consistent with NA and EU. HR (95% CI): Asia 1.07 (0.81, 1.42); NA 1.18 (0.90, 1.53); EU 1.03 (0.79, 1.36). Median PFS mos (95% CI) P: Asia 8.4 (8.3,11.1); EU 8.5 (8.0, 11....