Cabozantinib is a small molecule inhibitor of tyrosine kinases which include MET (hepatocyte growth factor receptor protein), VEGFR (vascular endothelial growth factor receptors), AXL, RET (Rearranged during transfection), FLT3 (Fms-like tyrosine kinase-3), KIT (mast/stem cell factor receptor), ROS1, MER, TYRO3, TRKB (Tropomyosin receptor kinase B) and TIE-2 (angiopoietins receptor). Similar to other TKIs, cabozantinib is a reversible, ATP-competitive inhibitor. Cabozantinib has thus demonstrated significant activity in metastatic clear cell renal cell carcinoma after failure of one or 2 tyrosine kinase inhibitors and is now approved in the second line setting in Europe. Some efficacy was also demonstrated in patients in first line treatment when compared to sunitinib.~Brain metastasis in renal cancer are difficult to treat and cytotoxic systemic therapies are still not used, given by the more or less impermeable blood-brain barrier. The interest of cabozantinib in brain renal cell carcinoma metastases is encouraged by 3 recent cases reports of significant responses of brain metastases including a complete response of brain metastases in one case. Moreover MET receptor surexpression appear more frequent in brain metastases than in other renal cell carcinoma tumor sites. Cabozantinib as multitarget inhibitor including VEGF and MET receptors suggest that it could be a good option. Its efficacy in brain metastases from renal cell carcinoma requires further evaluation.~On this basis, the investigators propose to conduct an open-label exploratory single arm, multicenter prospective phase II trial to assess the efficacy of cabozantinib on brain metastases in metastatic renal cell carcinoma patients.~Ancillary studies:~The relationship between serum markers and efficacy data will be investigated. Serum and plasma sample will be collected at Baseline. MET expression and MET sequencing will be also performed on available tumor tissues.
This is a multicenter, open-label, exploratory, single-arm, prospective phase II study to assess the efficacy and safety profile of cabozantinib in patients with brain metastases from metastatic renal cell carcinoma (mRCC).