Nivolumab plus ipilimumab versus sunitinib for first-line treatment of advanced renal cell carcinoma: extended 8-year follow-up results of efficacy and safety from the phase III CheckMate 214 trial

Background: Nivolumab plus ipilimumab (NIVO+IPI) has demonstrated superior overall survival (OS) and durable response benefits versus sunitinib (SUN) with long-term follow-up in patients with advanced renal cell carcinoma (aRCC). We report updated analyses with 8 years of median follow-up from CheckMate 214. Patients and methods: Patients with aRCC (N = 1096) were randomized to NIVO 3 mg/kg plus IPI 1 mg/kg Q3W × four doses, followed by NIVO (3 mg/kg or 240 mg Q2W or 480 mg Q4W); or SUN (50 mg) once daily for 4 weeks on, 2 weeks off. The endpoints included OS, independent radiology review committee (IRRC)-assessed progression-free survival (PFS), and IRRC-assessed objective response rate (ORR) in intermediate/poor-risk (I/P; primary), intent-to-treat (ITT; secondary), and favorable-risk (FAV; exploratory) patients. Results: With 8 years (99.1 months) of median follow-up, the hazard ratio [HR; 95% confidence interval (CI)] for OS with NIVO+IPI versus SUN was 0.72 (0.62-0.83) in ITT patients, 0.69 (0.59-0.81) in I/P patients, and 0.82 (0.60-1.13) in FAV patients. PFS probabilities at 90 months were 22.8% versus 10.8% (ITT), 25.4% versus 8.5% (I/P), and 12.7% versus 17.0% (FAV), respectively. ORR with NIVO+IPI versus SUN was 39.5% versus 33.0% (ITT), 42.4% versus 27.5% (I/P), and 29.6% versus 51.6% (FAV). Rates of complete response were higher with NIVO+IPI versus SUN in all International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) risk groups (ITT, 12.0% versus 3.5%; I/P, 11.8% versus 2.6%; FAV, 12.8% versus 6.5%). The median duration of response (95% CI) with NIVO+IPI versus SUN was 76.2 versus 25.1 months [59.1 months-not estimable (NE) versus 19.8-33.2 months] in ITT patients, 82.8 versus 19.8 months (54.1 months-NE versus 16.4-26.4 months) in I/P patients, and 61.5 versus 33.2 months (27.8 months-NE versus 24.8-51.4 months) in FAV patients. The incidence of treatment-related adverse events was consistent with previous reports. Exploratory post hoc analyses are reported for FAV patients, those receiving subsequent therapy based on their response status, clinical subpopulations, and adverse events over time. Conclusions: Superior survival, durable response benefits, and a manageable safety profile were maintained with NIVO+IPI versus SUN at 8 years, the longest phase III follow-up for a first-line checkpoint inhibitor combination therapy in aRCC.