Costs of Adverse Events in Patients with Advanced or Metastatic Renal Cell Carcinoma with First-Line Treatment

Aim This study evaluated costs associated with adverse events (AEs) in previously untreated real-world patients with advanced renal cell carcinoma (aRCC) in the USA. Materials and Methods This retrospective longitudinal cohort study analyzed data from the Merative MarketScan Research Database (1 January 2014–30 September 2021). Adult patients with aRCC receiving first-line systemic treatments for aRCC (tyrosine kinase inhibitors [TKIs], or combination therapies of TKIs and immunotherapy) on or after the date of aRCC diagnosis were included. A total of 27 AEs of interest were included based on a review of product labels of the first-line treatments included in the study and identified using International Classification of Diseases, Ninth/Tenth Revision, Clinical Modification codes. Incremental costs associated with AEs between cases and controls (unadjusted and adjusted for relevant baseline characteristics) were estimated by two-part modeling. Analyses were performed over three AE cost assessment periods (7, 14, and 30 days). Results The study included 1681 patients with aRCC (mean [standard deviation; SD] age, 60.8 [10.6] years; 73.1% male), of which 1542 (91.7%) had at least one AE. AEs were mostly diagnosed in the outpatient (OP) setting. For most AEs, cases had significantly higher unadjusted and adjusted costs than controls. Costs associated with AEs ranged from