Tokio Rationale and Protocol: A Phase II Study to Evaluate the Activity and Safety of Third-line Tyrosine Kinase Inhibitor after 2 Tyrosine Kinase Inhibitors in Patients with Metastatic Renal Cell Carcinoma

AIMS AND BACKGROUND: The introduction of agents targeting vascular endothelial growth factor has radically changed the approach to metastatic renal cell carcinoma (mRCC): sunitinib and pazopanib are now the standard first-line therapy in mRCC. At sunitinib failure, second-line axitinib or everolimus or sorafenib should be considered to improve the clinical outcome. No data are available for a third-line tyrosine kinase inhibitor (TKI) after 2 previous lines of therapy with TKIs. At pazopanib failure, no prospective data are available. STUDY DESIGN: The TOKIO study was designed to evaluate progression-free survival, safety, and efficacy of third-line therapy with TKI in 44 patients already treated with 2 previous lines of TKIs in 10 Italian centers, and relapsed from sunitinib-axitinib (group A) or pazopanib-sorafenib (group B). Standard treatment is sorafenib in group A and sunitinib in group B, administered until disease progression or unacceptable toxicity. Secondary endpoints include the evaluation of overall survival, safety, and quality of life.