The rapid increase in total payments for GLDs may not reflect the change in actual economic burden, because a growing portion of the total payments were returned to the payers in the form of manufacturer rebates. This study explored trends in rebates for GLDs from 2010-17. We defined total payments as the retail amount the pharmacy received, including two components:

  • 1) rebates, the estimated proportion of the total payments retroactively passed through to pharmacy benefit managers and the payers; and

  • 2) net payments, the net spending for the GLDs. We used data from the 2010-17 Medical Expenditure Panel Survey to estimate the total payments including out-of-pocket payments, and data from the SSR Health and Medicaid programs to estimate the net payments and rebates.

Four high-cost GLDs were included in this study: basal insulin, bolus insulin, GLP-1 Receptor Agonists (GLP-1RA) , and SGLT2 inhibitors (SGLT2i) . Costs were adjusted to 2017 U.S. dollars. While the total payments for a 30-day supply of bolus insulin, basal insulin and GLP-1RA increased by almost 200% from 20 to 2017, the rebates increased by more than 300%, attenuating the increase in net payments. By 2016-17, rebates accounted for 59%, 54%, 37%, and 49% of total payments for bolus insulin, basal insulin, GLP-1RA, and SGLT2i, respectively (Figure 1) . Our study is the first to quantify rebates for GLDs by class from a payer’s perspective.


Y.Ding: None. L.Shi: None. Y.Lin: None. H.Shao: Board Member; BRAVO4HEALTH, LLC.

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