Abstract
BACKGROUND: Immunotherapy (IO) and oral anticancer agents (OAA) have improved outcomes for metastatic renal cell carcinoma (mRCC), but there is a need to understand real-world costs from the perspective of payers and patients. METHODS: We used retrospective fee-for-service Medicare 100% claims data to study patients diagnosed with mRCC in 2015-2019. We identified initial treatment type and costs (the year after diagnosis) and analyzed differences in monthly and 12-month costs over time and between OAA, IO, and combination groups and the association between Out-Of-Pocket (OOP) costs and adherence. RESULTS: We identified 15 407 patients with mRCC (61% male; 85% non-Hispanic White). A total of 6196 received OAA, IO, or combination OAA/IO as initial treatment. OAA use decreased (from 31% to 11%) with a simultaneous rise in patients receiving IO (3% to 26%) or combination IO/OAA therapy (1% to 11%). Medicare payments for all patients with mRCC increased by 41%, from $60 320 (95% confidence interval = 58 260 to 62 380) in 2015 to $85 130 (95% confidence interval = 82 630 to 87 630) in 2019. Payments increased in patients who received OAA, IO, or combination OAA/IO but were stable in those with other/no treatment. Initial higher OOP responsibility ($200-$1000) was associated with 13% decrease in percent days covered in patients receiving OAA in the first 90 days of treatment, compared with those whose OOP responsibility was less than $200. CONCLUSION: From 2015 to 2019, costs for Medicare patients with mRCC rose substantially due to more patients receiving IO or IO/OAA combined therapy and increases in costs among those receiving those therapies. Increased OOP costs was associated with decreased adherence.