A new study examines the potential impact of the Medicare Prescription Payment Plan (M3P) - an opt-in policy implemented in 2025 under the Inflation Reduction Act that allows beneficiaries to spread out of pocket (OOP) costs over the calendar year - on Medicare Part D beneficiaries with cancer who face high out-of-pocket (OOP) prescription drug costs. Many cancer patients enrolled in Part D incur thousands of dollars in OOP expenses at the start of the year to quickly reach the catastrophic coverage threshold, after which cost-sharing drops to zero. For patients living on fixed or limited incomes, these large upfront payments can be unmanageable, contributing to delayed treatment initiation, medication nonadherence, financial distress and poorer health outcomes.

Using Medicare 2022 claims data from a national sample of beneficiaries with cancer, the researchers analyzed when patients typically reach the catastrophic cap and modeled how M3P could alter payment patterns. The analysis found that nearly half of Medicare Part D beneficiaries with cancer are projected to reach the annual OOP cap, with about one-third doing so as early as January 2025. Under current structures, this results in highly front-loaded costs. Enrollment in M3P - which allows beneficiaries to spread OOP payments evenly across the year - substantially reduced monthly payment volatility, particularly for those who reach catastrophic coverage early, and could help mitigate cost-related nonadherence.

Importantly, the study highlights that awareness and uptake of M3P remain extremely low, limiting its potential benefits. The Centers for Medicare and Medicaid Services (CMS) estimates that 2.4 million (6 %) of Part D beneficiaries could benefit from enrolling in M3P. Aryana Sepassi, PharmD, MAS, assistant professor of clinical pharmacy at the University of California San Diego Skaggs School of Pharmacy and Pharmaceutical Sciences and colleagues conclude that making the program automatic, rather than opt-in, could significantly expand its impact, reduce financial burden for vulnerable patients, and support more consistent adherence to life-sustaining cancer therapies.

The study was published Jan. 15, 2026, in the Journal of Clinical Oncology.