LBA4 Adjuvant nivolumab plus ipilimumab (NIVO+IPI) vs placebo (PBO) for localized renal cell carcinoma (RCC) at high risk of relapse after nephrectomy: Results from the randomized, phase III CheckMate 914 trial

Abstract

CheckMate 914 (NCT03138512) is a phase III, randomized, double-blind, multicenter, 2-part trial evaluating NIVO+IPI vs PBO (part A) or NIVO monotherapy vs NIVO+IPI vs PBO (part B) in mutually exclusive patients (pts) with localized RCC at high risk of post-nephrectomy relapse. We report the primary analysis for part A of this trial. CheckMate 914 key inclusion criteria: radical or partial nephrectomy with negative surgical margins > 4 and ≤ 12 weeks before randomization; predominant clear cell histology; pathological TNM stage T2a (grade [G] 3 or 4) N0M0, T2b (any G) N0M0, T3 (any G) N0M0, T4 (any G) N0M0, or any T (any G) N1M0; and no clinical/radiological evidence of residual disease or distant metastases. Pts were randomized 1:1 to NIVO 240 mg Q2W (× 12 doses) + IPI 1 mg/kg Q6W (× 4 doses) or equivalent PBO for 24 weeks or until disease recurrence/unacceptable toxicity. Stratification factors: TNM stage and type of nephrectomy. Primary endpoint: disease-free survival (DFS) per blinded independent central review; secondary endpoints include overall survival and safety. 816 pts were randomized to NIVO+IPI (n = 405) vs PBO (n = 411). With 37.0 months of median follow-up (range, 15.4–58.0), the primary efficacy endpoint of DFS was not met (HR, 0.92; 95% CI, 0.71–1.19; P = 0.5347). Median DFS was not reached with NIVO+IPI and 50.7 months with PBO; DFS probabilities at 24 months were 76.4% and 74.0%, respectively. Median (Q1, Q3) treatment duration was 5.1 (2.8, 5.3) months and 5.1 (5.1, 5.3) months, respectively. Any-grade treatment-related adverse events (AEs) were reported in 88.9% vs 56.8% of pts treated with NIVO+IPI vs PBO; grade ≥ 3 treatment-related AEs were reported in 28.5% vs 2.0%, respectively. Treatment-related AEs led to discontinuation of NIVO+IPI in 29.0% of pts and of PBO in 1.0% of pts. The CheckMate 914 trial of NIVO+IPI vs PBO in pts with localized RCC at high risk of relapse after nephrectomy did not meet the primary endpoint of DFS. Safety of NIVO+IPI was consistent with its known profile in advanced RCC, although the rate of discontinuation due to treatment-related AEs was higher with adjuvant NIVO+IPI vs PBO in this trial.