Medicare Part D Formulary Coverage of Humira Biosimilars

Humira-one of the best selling prescription drugs in the world and one of the most costly drugs for the Medicare Part D program-faced its first competition in the United States in 2023, ending nearly 20 years of market exclusivity. Launches of multiple biosimilars for Humira in 2023, including one interchangeable version, have presented an opportunity to increase access to lower cost drugs and, ultimately, significantly reduce Part D drug spending. However, a lack of Part D formulary coverage for Humira's biosimilars, or preferential formulary placement for Humira, could limit the wider use of these biosimilars, as well as limit any potential spending reductions for the Part D program and its enrollees. Our study will determine how often Part D formularies covered Humira biosimilars after they became available and describe differences in cost-sharing or utilization management requirements, as well as list prices, for Humira and its biosimilars.

Announced or Revised	Agency	Title	Component	Report Number(s)	Expected Issue Date (FY)
November 2023	Centers for Medicare and Medicaid Services	Medicare Part D Formulary Coverage of Humira Biosimilars	Office of Evaluation and Inspections	OEI-05-23-00520	2025