Phase II Trial of Cabozantinib Plus Nivolumab in Patients With Non–Clear-Cell Renal Cell Carcinoma and Genomic Correlates

PURPOSE: To assess the efficacy and safety of cabozantinib plus nivolumab in a phase II trial in patients with non-clear-cell renal cell carcinoma (RCC). PATIENTS AND METHODS: Patients had advanced non-clear-cell renal carcinoma who underwent 0-1 prior systemic therapies excluding prior immune checkpoint inhibitors. Patients received cabozantinib 40 mg once daily plus nivolumab 240 mg once every 2 weeks or 480 mg once every 4 weeks. Cohort 1 enrolled patients with papillary, unclassified, or translocation-associated RCC; cohort 2 enrolled patients with chromophobe RCC. The primary end point was objective response rate (ORR) by RECIST 1.1; secondary end points included progression-free survival, overall survival, and safety. Next-generation sequencing results were correlated with response. RESULTS: mutations. CONCLUSION: Cabozantinib plus nivolumab showed promising efficacy in most non-clear-cell RCC variants tested in this trial, particularly those with prominent papillary features, whereas treatment effects were limited in chromophobe RCC. Genomic findings in non-clear-cell RCC variants warrant further study as predictors of response.