Cabozantinib in Patients with Advanced Merkel Cell Carcinoma.

Cabozantinib was poorly tolerated and did not demonstrate activity in patients with recurrent/metastatic, platinum-failure MCC. It is unclear whether preselection of patients with the specific upregulation or genetic alteration in the targets for cabozantinib would have changed the results of this study. (Clinical trial identification number: NCT02036476) IMPLICATIONS FOR PRACTICE: This phase II study demonstrated poor tolerability and lack of activity of cabozantinib in an unselected group of patients with advanced Merkel cell carcinoma. Although it is unclear whether preselection of patients with the specific upregulation and genetic alterations in targets for cabozantinib would have changed the results of this study, this would have likely led to an extremely rare patient population that would take many years to accrue.