Combination of Recombinant Human IL-21 (rIL-21) and Sunitinib in Stage IV Renal Cell Carcinoma Patients

Inclusion Criteria: * Histologically verified and surgically incurable stage IV Renal Cell Carcinoma * ECOG performance status of 0 or 1 (i.e. good performance status) * Life expectancy of at least 3 months Exclusion Criteria: * Prior systemic therapy for metastatic disease * Radiotherapy within the last 4 weeks prior to start of treatment * Receipt of any investigational drug within 3 months of starting treatment * History of any other active malignancy within five years prior to enrolment