Utilization and Safety of Ipilimumab Plus Nivolumab in a Real-World Cohort of Metastatic Renal Cell Carcinoma Patients

INTRODUCTION: Ipilimumab plus nivolumab was associated with a survival benefit in a phase III clinical trial of first-line treatment for metastatic renal cell carcinoma (mRCC). In this study, mRCC patients from the Canadian Kidney Cancer Information System (CKCis) database who received first-line ipilimumab plus nivolumab were analyzed to determine the safety and outcomes in a real-world setting. PATIENTS AND METHODS: Patients who received ipilimumab plus nivolumab as first-line therapy for mRCC in CKCis, were identified, and the amount of treatment received, discontinuation rates, and reasons for discontinuing treatment were determined. Toxicity data, including type and grade, were collected. Efficacy outcomes of interest included overall survival (OS), progression-free survival (PFS), and overall response rate (ORR). RESULTS: The cohort included 195 patients, the majority with clear cell histology (74%). All 4 cycles of ipilimumab plus nivolumab were administered in 124 patients (64%). Progressive disease (n = 87; 45%) and toxicity (n = 36; 18%) were the most common causes for discontinuing treatment. Several patients (n = 18) did not receive all 4 doses of ipilimumab but received single agent nivolumab. The estimated median OS was 54.5 months (95% CI, 17.7 - NE) and 12-month OS was 72.2% (95% CI, 65.0 - 79.3). Median PFS was 7.4 months (95% CI 5.3 - 10.2) and ORR was 42.5%. Patients who received all 4 cycles of ipilimumab plus nivolumab had better ORR (50% vs. 28%) and a longer PFS and OS than those who received less than 4 cycles (P < .0001). Ninety-five AEs were documented in 72 patients who required dose reduction/change, with colitis being the most frequent. CONCLUSION: In this real-world cohort of treatment-naïve mRCC patients, outcomes, and safety were comparable to previously reported clinical trial data.