Evaluation of the safety and efficacy of pazopanib , a multikinase angiogenesis inhibitor , in a single-arm , open-label , extension study ( VEG107769/NCT00387764 ) for placebo-treated patients with advanced renal cell carcinoma ( RCC ) from a randomized , double-blind , placebo-controlled phase III study ( VEG105192/NCT00334282 ) .