Study Overview
Objective. To evaluate the efficacy and safety of the combination of nivolumab plus cabozantinib as compared with sunitinib monotherapy in the treatment of previously untreated advanced renal cell carcinoma (RCC).
Design. Multicenter, international, open-label, randomized, phase 3 trial.
Intervention. Patients were randomized in a 1:1 fashion to 1 of 2 treatment arms:
- Arm A: Nivolumab intravenously 240 mg every 2 weeks plus cabozantinib orally 40 mg once daily.
- Arm B: Sunitinib orally 50 mg daily for 4 weeks, followed by 2 weeks off therapy (6-week cycle).
Randomization was stratified by the International Metastatic RCC Database Consortium prognostic risk score (low-, intermediate-, and high-risk). Treatment was continued until disease progression or development of unacceptable toxic side effects with a maximum of 2-year duration of Nivolumab therapy.
Settings and participants. Adults with previously untreated advanced RCC with a clear cell component were eligible for enrollment. Subjects were excluded if they had active central nervous system metastases or active autoimmune disease.
Main outcome measures. The primary outcome of this study was progression-free survival (PFS) as assessed by an independent review committee. Secondary endpoints included overall survival, objective response rate, safety, and PFS as assessed by investigators. All subgroup analyses were prespecified. Efficacy was assessed in the intention-to-treat population, including all patients who underwent randomization.
Main results. A total of 651 patients underwent randomization: 323 to the nivolumab plus cabozantinib group, and 328 to the sunitinib group. Baseline demographics were balanced. The median follow-up period for overall survival (OS) was 18.1 months. The primary reason for treatment discontinuation in any group was disease progression. PFS as indicated by an independent review committee was significantly longer in the nivolumab plus cabozantinib group compared to the sunitinib group (median 16.6 months vs 8.2 months; hazard ratio [HR] 0.51, P < .001). The median OS was not reached for any group. Overall survival was longer in the nivolumab plus cabozantinib group compared to the sunitinib group (HR 0.60, 95% CI: 0.40-0.89; P = .001). The objective response rate was 55.7% with the nivolumab plus cabozantinib group versus 27.1% with sunitinib (P < .001). The complete response rate was 8% in the nivolumab plus cabozantinib group compared to 4.6% in the sunitinib group. The median time to response was 2.8 months with nivolumab plus cabozantinib and 4.2 months in the sunitinib group, while the median duration of response was 20.2 months and 11.5 months, respectively.