The Inflation Reduction Act's cap on out-of-pocket insulin costs for Medicare beneficiaries was associated with reduced expenses and increased insulin use among a subset of U.S. patients, according to a study published in JAMA on June 8.
Researchers from Emory University, University of Southern California, and University of Wisconsin-Madison analyzed the impact of the $35 monthly cap on more than 2.8 million Medicare Part D beneficiaries who use insulin. The study compared out-of-pocket spending per 30-day supply, number of monthly fills, adherence rates, and persistence before and after the policy took effect in 2023.
The researchers found that while some patients benefited from lower costs and improved access to insulin under the new policy, only a small portion of U.S. users were affected by the change. The authors highlighted that skipping prescribed doses due to cost concerns can put people with diabetes at risk for avoidable and potentially life-threatening health complications.
The study was funded by a grant from the National Institute of Diabetes and Digestive and Kidney Diseases. It also referenced data from The IQVIA Institute indicating that if a universal $35 cap applied to all insulin prescriptions nationwide, Americans would have saved $170 million in out-of-pocket expenses in 2024.
"Making sure patients take their medication should be a greater clinical priority. This research demonstrates a powerful policy lever for doing so: reducing their out-of-pocket costs," said Dana Goldman, PhD, founding director of the USC Schaeffer Institute for Public Policy & Government Service.
