First-line therapy for treatment-naive patients with advanced/metastatic renal cell carcinoma: a systematic review of published randomized controlled trials.

In the recent years, a number of targeted therapies have been approved for first-line treatment of patients with metastatic renal cell carcinoma. A systematic review was conducted to assess the clinical efficacy, safety and effect of all first-line treatments evaluated to date on health-related quality of life (HRQoL). A systematic search of Embase, Cochrane and MEDLINE databases was performed to identify randomized controlled trials (1980-2015) evaluating any targeted therapy/immunotherapy against placebo or any other targeted intervention/immunotherapy in treatment-naive patients with metastatic renal cell carcinoma. Conference proceedings from major cancer congresses (2007-2015) were handsearched. Sixteen randomized controlled trials were identified, mostly phase III. Overall, targeted therapies were associated with either improved [sunitinib, bevacizumab+interferon α (IFNα) and temsirolimus] or comparable (sorafenib) progression-free survival (PFS) versus IFNα monotherapy. Sunitinib demonstrated comparable PFS and overall survival to pazopanib, comparable PFS to sorafenib and shorter PFS compared with bevacizumab+IFNα (although no conclusions were made with regard to superiority/inferiority). Compared with sorafenib, tivozanib demonstrated a significantly longer PFS, and both tivozanib and axitinib demonstrated higher response rates. Nintedanib demonstrated comparable PFS and overall survival to sunitinib in a phase II trial. Temsirolimus, sunitinib and sorafenib treatment led to better HRQoL versus IFNα; pazopanib was associated with better HRQoL versus sunitinib. No direct meta-analyses or indirect treatment comparison analysis were undertaken because of noncomparability of the trials. In general, targeted therapies demonstrated favourable clinical efficacy and improved HRQoL compared with IFNα monotherapy. The newer therapies, tivozanib and axitinib (but not nintedanib), appeared to exhibit greater clinical benefit (response rate) than older tyrosine kinase inhibitors.