Estimated True Out-of-Pocket Cost Changes From the Inflation Reduction Act on Medicare Part D Beneficiaries With Cancer.

Objectives: To estimate changes in true out-of-pocket (TrOOP) spend from implementation of a $2000 cap for outpatient prescriptions as authorized by the 2022 Inflation Reduction Act (IRA) among Medicare Part D beneficiaries who received a diagnosis of cancer.

Methods: Medicare beneficiaries who received a diagnosis of cancer and at least one Part D claim for a prescription drug to treat cancer in 2021 were identified from a 5% random sample of beneficiaries. Part D drug expenditures were extracted and adjusted to 2025 expenditures using previously published methods. Total annual TrOOP spend per beneficiary was estimated under 2 scenarios: (1) 2025 Part D design expected without any IRA policies implemented and (2) IRA design with a $2000 TrOOP cap. We reported the proportion of beneficiaries who would experience TrOOP spend changes with the cap and estimated differences in TrOOP spend for these individuals.

Results: An estimated 42% of Part D beneficiaries with a diagnosis of cancer were predicted to have annual TrOOP spend of more than $2000 without the Part D cap. With the cap, these beneficiaries were expected to experience an average annual reduction of $8486 in TrOOP spend. Among these beneficiaries, with the TrOOP cap, those with hematologic cancers were expected to experience the greatest reduction ($10 846/beneficiary).

Conclusions: Implementation of a Part D $2000 cap is expected to generate meaningful reduction in TrOOP spend for high-cost Medicare Part D beneficiaries who received a diagnosis of cancer.