Antibody-drug conjugate use and spending in the United States, 2013–2022
Paul R Shafer, Hooman Y Farsani, Haoran Tao, Aaron P MitchellIntroduction
Antibody-drug conjugates (ADC) are a class of pharmaceuticals that combine monoclonal antibodies with cytotoxic drugs, aiming to treat cancer while minimizing off-target toxicity. They are a small class but growing in importance, as evidenced by high commercial investment. Our objective is to describe the use of and spending on ADCs across commercial and public payers in the US.
Methods
We used four data sources to capture ADC use and costs in the US from 2013 to 2022—1) Merative™ MarketScan ® Commercial Database, 2) Centers for Medicare and Medicaid (CMS) Medicaid State Drug Utilization Data, 3) CMS Medicare Part B Spending by Drug, and 4) Medicare Part D Spending by Drug.
Results
Traditional Medicare (Parts B and D) spent over $3.6 million per 100,000 enrollees on ADCs in 2022 compared with over $1.1 million per 100,000 enrollees in a national sample of commercial insurance plans (MarketScan). Irrespective of differences in volume, commercial payers were paying approximately 91% more for ADCs per patient than Medicare Part B in 2022. Although we could not measure Medicaid spending on ADCs, relative growth in Medicaid prescription volume per 100,000 enrollees over the study period was also strong, increasing more than six times.
Conclusions
Use of ADCs has increased dramatically in recent years, with rates of use more than tripling within Medicare Part B and more than doubling within employer-sponsored coverage from 2019 to 2022. This growth coupled with wide variation in reimbursement between ADCs and across public and private payers suggests a need for further evidence of comparative and cost effectiveness in this growing class, particularly as it expands to non-oncological uses, to inform clinical decision making and improve patient outcomes.