Impact of Inflation Reduction Act on Insulin Prices for Medicare Beneficiaries

A recent analysis from Johns Hopkins Bloomberg School of Public Health reveals the impact of legislative mandates on insulin prices for Medicare Part D enrollees. The study evaluated the Inflation Reduction Act of 2022, which imposed a $35 monthly out-of-pocket limit starting January 1, 2023, marking the first federal cap specifically for Medicare beneficiaries using insulin. This policy aims to enhance insulin access and affordability.

Researchers analyzed Medicare claims data from 2019 to 2023, examining approximately 3.8 million patients with insulin prescriptions. Findings showed that by 2023, 75% of these patients paid no more than $35 for a 30-day supply, a significant rise from 48% in 2019. Published in JAMA, the study found that the average out-of-pocket expense decreased from $50.87 in 2019 to $21.98 in 2023. Despite improvements, about 25% of beneficiaries paid more due to prescriptions not prorated under the new rule.

The Centers for Medicare & Medicaid Services (CMS) previously initiated a voluntary cap in 2021, paving the way for this mandatory reduction affecting millions managing diabetes. Under CMS guidelines, if prescriptions do not fit exactly into 30-day multiples, higher costs may result. For example, a 45-day supply might be billed as a 60-day supply. Costs varied by state, with averages ranging from $10.36 in Washington, D.C., to $31.09 in Minnesota. Ongoing research aims to assess state-level prescription prorating to inform potential policy adjustments. The study was funded by the National Institute of Diabetes and Digestive and Kidney Diseases.