The goal of the thesis was the assessment of the effects of immunotherapies in comparison to standard targeted therapies for the treatment of metastatic renal cell carcinoma and to evaluate the quality of evidence. Summarizing the evidence, IFN- monotherapy in first-line-therapy is inferior to standard targeted therapies. Non-specific immunotherapy with interferon-α should be used only as part of combination therapy with bevacizumab. For patients who had already undergone systemic treatment, one study with nivolumab, a novel PD-1/ PD-L1 immune checkpoint inhibitor, improved average survival by more than five months when compared to the targeted standard therapy, everolimus. The effects are accompanied by better quality of life and fewer major side effects. A major challenge for further projects remains the identification of specific biomarkers to optimize patient selection and to predict a response to the new immune checkpoint inhibitors.