Future Treatment Options in Metastatic Clear Cell Renal Cell Carcinoma

The field of clear cell renal cell carcinoma (ccRCC) has undergone major changes in the last decade, both in terms of the understanding of the mechanisms of oncogenesis and the role of the tumor microenvironment in anti-tumor immunity, as well as in therapeutic developments. After the era of tyrosine kinase inhibitors (TKIs) targeting VEGFR and then the era of immune checkpoint inhibitors (ICIs) targeting the PD-1/PD-L1 pathway, we are now entering the era of combination therapy for first-line metastatic cancer (m-ccRCC), such as combinations including a TKI and a PD-1 inhibitor or combinations of PD-1 and CTLA-4 blockers. In this extremely dynamic environment, new molecules with various mechanisms of action will appear in the very near future: immune response modulators (other ICIs, pro-inflammatory cytokines, gut microbiota modulators), new anti-angiogenic agents (new TKIs, anti-HIF-1α antibodies), agents affecting cell metabolism (glutaminase inhibitors, tryptophan regulators or adenosine A2A receptor antagonists) or epigenetic regulators (HDAC inhibitors). In parallel, new strategies are being evaluated that could rapidly change the standards of management of advanced disease, including therapeutic intensification with triple combinations or, conversely, adaptive and/or alternative de-escalation regimens (SURF trial), and biomarker-driven treatments (BIONIKK trial). The main new molecules and strategies currently being evaluated are reviewed in this article.