Cabozantinib Plus Nivolumab in Patients with Non–Clear Cell Renal Cell Carcinoma: Updated Results from a Phase 2 Trial

Treatment options are limited for patients with non–clear cell renal cell carcinoma (nccRCC). Patients with nccRCC experienced a favorable objective response rate (ORR) in a phase 2 trial of cabozantinib plus nivolumab. We now report updated efficacy and safety results at median follow-up of 34 mo for patients with papillary, unclassified, or translocation-associated RCC. Cabozantinib and nivolumab were administered at standard doses to patients with metastatic nccRCC that had progressed on zero or one line of systemic therapy. The primary endpoint was the ORR according to Response Evaluation Criteria in Solid Tumors v1.1. Secondary endpoints included progression-free survival (PFS), overall survival (OS), and adverse events. Forty patients were treated. At median follow-up of 34 mo for survivors, the ORR was 48% (95% confidence interval [CI] 31.5–63.9%). Median PFS was 13 mo (95% CI 7–16); the 12-mo and 24-mo PFS rates were 51% (95% CI 34–65%) and 23% (95% CI 11–37%), respectively. Median OS was 28 mo (95% CI 23–43); the 18-mo and 36-mo OS rates were 70% (95% CI 53–82%) and 44% (95% CI 28–60%), respectively. No new safety signals were seen with cabozantinib and nivolumab. This extended follow-up analysis demonstrates promising efficacy, and highlights the potential for sustained responses with cabozantinib plus nivolumab in patients with metastatic nccRCC. We evaluated outcomes for patients with metastatic kidney cancer of the non–clear cell (NCC) type who were treated with cabozantinib + nivolumab. We found that 48% of the patients responded to the treatment, and there were no unexpected side effects. Among patients who responded to the treatment, the response lasted for a median of 17 months. We conclude that cabozantinib + nivolumab is a safe and effective treatment for NCC kidney cancer.