Second-Line Treatment Landscape for Renal Cell Carcinoma: A Comprehensive Review

Abstract

The management of advanced clear-cell renal cell carcinoma has steadily improved over the past decade with the introduction of antiangiogenic and targeted therapies. Recently, three new therapies have been approved for use as second-line options that further advance the treatment armamentarium: nivolumab, a monoclonal antibody targeting the programmed cell death receptor; cabozantinib, a small-molecule tyrosine kinase inhibitor (TKI) of vascular endothelial growth factor receptor (VEGFR), MET, and AXL; and lenvatinib, a small-molecule TKI of VEGF and fibroblast growth factor receptors that is used in combination with everolimus, an inhibitor of the mechanistic target of rapamycin. Together, these and previously approved second-line treatments offer clinicians the ability to better individualize treatment for patients after progression on first-line VEGFR-targeted therapies. In this comprehensive review, we discuss the efficacy and safety results from the pivotal trials of these newly approved therapies, including the quality of study design, the level of evidence, subgroup analyses, and how these data can help to guide clinicians to select the most appropriate second-line therapy for their patients.

Implications for practice: This review article provides the reader with a comprehensive overview of current treatment options for patients with advanced clear-cell renal cell carcinoma (RCC) whose disease has progressed after their first therapy. As many patients with RCC experience disease progression with initial treatments, effective second-line therapies are critical. Nivolumab, cabozantinib, and lenvatinib plus everolimus have recently been approved as second-line treatments. The new agents discussed in this review increase the therapeutic options available and provide physicians with opportunities to individualize treatments for their patients, with a view to improving disease control and survival outcomes.

Keywords: Axitinib; Cabozantinib; Everolimus; Lenvatinib; Nivolumab; Renal cell carcinoma.

Figure 1.

Therapeutic targets in advanced renal cell carcinoma (RCC). (A): Established second‐line targets: activation receptor tyrosine kinases, including VEGFR [22], MET [28], AXL [29], and FGFR [88], can promote tumorigenesis and angiogenesis [22], [88], [89], [90]; AXL, MET, and FGFR may also act as compensatory mechanisms of angiogenesis [30], [32]; PD‐L1/PD‐L2 on tumor cells and APCs suppress effector T‐cell activity in the tumor microenvironment, facilitating tumor immune evasion [33]. (B): Immunomodulatory targets for tyrosine kinase inhibitors (TKIs)—rationale for combination with checkpoint inhibitors in RCC. TKIs have been shown, generally in ex vivo or non‐VHL tumor models, to modulate (suppress [red line] or stimulate [green arrow]) the activity of immune cells (e.g., activation, migration, proliferation, expansion, recruitment) involved in the tumor‐immune response, including CD8+ T cells [91], [92], CD4+ T cells [92], [93], T_reg cells [91], [92], [93], [94], [95], [96], APC [97], [98], [99], tumor‐associated macrophages [91], MDSC [91], [93], [96], [100], [101], and NK cells [102]. Abbreviations: APC, antigen‐presenting cell; CD, cluster of differentiation; CTLA‐4, cytotoxic T‐lymphocyte‐associated protein 4; FGF, fibroblast growth factor; FGFR, fibroblast growth factor receptor; GAS6, AXL receptor tyrosine kinase ligand; HGF, hepatocyte growth factor; HIFα, hypoxia‐inducible factor alpha; IL‐10, interleukin 10; MDSC, myeloid‐derived suppressor cell; MHC, major histocompatibility complex; mTOR, mechanistic target of rapamycin; NK, natural killer; PD‐1, programmed cell death receptor 1; PDGF, platelet‐derived growth factor; PDGFR, platelet‐derived growth factor receptor; PD‐L1/L2, programmed cell death‐ligand 1 or 2; TCR, T‐cell receptor; T_eff, effector T cell; TGF‐β, transforming growth factor‐β; T_reg cell, regulatory T cell; VEGF, vascular endothelial growth factor; VEGFR, vascular endothelial growth factor receptors; VHL, von Hippel‐Lindau.