Trends in anti-seizure medication spending by Medicare Part D and Medicaid from 2012 to 2022

The rising cost of anti-seizure medications (ASMs) in the United States (US) is a major concern for patients, healthcare providers, insurance payors, and policymakers. We aim to describe and analyze the spending trends on ASMs in the Medicare Part D (MPD) and Medicaid population in the US.

A retrospective study was conducted on the databases of MPD and Medicaid Spending by Drug from 2012 to 2022, which was published by the Centers for Medicare and Medicaid Services (CMS). The total expenditures (adjusted for inflation to 2022 dollars), number of claims, and cost-per-claim (CPC) for individual ASMs were summarized on an annual basis. Stratifications of ASMs were made by ASM generations and brand versus generic manufacturers.

Expenditure on ASM by both MPD and Medicaid more than doubled between 2012 and 2022, soaring from $2.8 billion to $5.7 billion. The ASMs total annual claim number increased from 32.2 to 43.2 million. In 2012, second-generation ASMs comprised the largest percentage of total spending of MPD (51%) and Medicaid (57%), but third-generation ASMs took over the lead in 2022 (44% of MPD and 68% of Medicaid). The total spending by MPD and Medicaid on brand-name ASMs increased significantly from 2012 to 2022, likely contributed by almost tripling of CPC of brand-name ASMs in 2022. There was no significant change in CPC for generic ASMs from 2012 to 2022.

The expenditure by MPD and Medicaid on ASMs has doubled in the past decade. The rise in spending was disproportionately comprised of newer third-generation and brand-name ASMs. Further monitoring of the spending trend and efforts on drug price negotiation may play a role curbing the rising cost of ASMs. The methods to control drug spending remain unclear and drug pricing negotiation and other policy reforms should be considered.