Clinical and Economic Outcomes in Elderly Advanced Renal Cell Carcinoma Patients Starting Pazopanib or Sunitinib Treatment: A Retrospective Medicare Claims Analysis

INTRODUCTION Studies indicate similar survival and toxicity between pazopanib and sunitinib, but few have examined real-world outcomes among elderly patients with advanced renal cell carcinoma (RCC). The purpose of this retrospective claims analysis was to assess real-world overall survival (OS), healthcare resource utilization (HRU), and healthcare costs (both all-cause and associated with RCC diagnosis) among elderly advanced RCC patients starting pazopanib or sunitinib treatment. METHODS Advanced RCC patients aged 65 years or older who started first-line treatment with pazopanib or sunitinib (index drug; the initiation date was the index date) were identified from the 100% Medicare database plus Part D linkage (January 1, 2006 to December 31, 2014). Patients were stratified by index drug and matched 1:1 with use of propensity scores based on baseline characteristics. OS was assessed from the index date to death and compared by Kaplan-Meier analyses and univariable Cox models; patients were censored at the end of eligibility/data. Monthly HRU and costs from an intent-to-treat perspective were compared by Wilcoxon signed-rank tests. RESULTS Baseline characteristics were balanced after matching (both N = 522). Treatment with pazopanib was associated with significantly longer median OS compared with treatment with sunitinib (18.2 months vs 14.6 months, respectively; log-rank p = 0.015). Pazopanib was associated with significantly lower monthly all-cause costs compared with sunitinib ($8845 vs $10,416, respectively), as well as lower inpatient costs associated with RCC diagnosis ($1542 vs $2522), fewer monthly inpatient admissions (0.179 vs 0.262), and shorter length of inpatient stay (1.375 days vs 1.883 days; all p ≤ 0.004). CONCLUSIONS Among elderly Medicare patients with advanced RCC, first-line pazopanib tretament was associated with significantly longer OS, as well as lower healthcare costs and HRU, compared with first-line sunitinib treatment.