Real-world outcome study among patients with renal cell carcinoma (RCC) receiving checkpoint inhibitors (CPIs).

Abstract

e16073 Background: North America has one of the highest rates of RCC, and in 2018, 65,340 new cases were diagnosed in the US alone. Tyrosine kinase inhibitors have been a mainstay treatment for RCC. However, the first CPI, nivolumab, was approved by the FDA as a second-line treatment for RCC in late 2015 and as a first-line therapy in combination with ipilimumab in 2018. In this study, real-world outcomes in patients with RCC receiving CPIs were examined. Methods: An observational study was conducted from March 1, 2015, to December 31, 2017, using the Premier Healthcare Database, a hospital discharge database. Patients with RCC aged ≥18 years were identified by ICD-9/10 codes and were included if they received a CPI during the study period, irrespective of treatment line. Comorbidities were assessed in a 6-month look-back period commencing at the time of first CPI treatment and RCC diagnosis. 34 distinct immune-related adverse events (irAEs) were identified in a 90-day look-back period from time of the irAE to determine if patients had received a CPI during that time. Patients were followed for 90 days after the irAE to determine if CPI treatment was reinitiated. Results: During the study period, 1228 patients with RCC received a CPI, of whom 719 (59%) had ≥1 irAE. Approximately 95% of patients received nivolumab and the remaining 5% received an off-label CPI. At the time of initial CPI treatment, patients who experienced any irAE during the study period had a higher Charlson Comorbidity Index (5.1±3.2 vs 4.2±3.0; p < 0.001) and were more likely to be hospitalized on an emergent basis than those without an irAE (9.0% vs 5.1%; p = 0.005). Patients with an irAE also had a higher average number of previous immune-related or immunocompromised comorbid conditions (0.33±0.57 vs 0.12±0.36; p < 0.001). After experiencing an irAE, 65% of patients reinitiated a CPI within 90 days. Conclusions: The majority of RCC patients receiving a CPI, mostly anti-PD-1 agents, experienced an irAE, and patients with irAEs had a higher comorbidity burden than those without irAEs. Most patients with irAEs reinitiated CPI treatment within 90 days.