(C-106) Trends in Utilization, Spending, and Pricing of Janus Kinase (JAK) Inhibitors in the U.S. Medicaid Program (2011-2023)

Background: The introduction of Janus kinase (JAK) inhibitors has transformed the management of autoimmune and inflammatory diseases, providing substantial therapeutic benefits. However, these treatments are associated with high costs, posing financial challenges for healthcare systems, particularly Medicaid. Understanding trends in JAK inhibitor utilization and spending is critical for evaluating economic sustainability and policy implications.

Objectives: This study aims to examine utilization, spending, and pricing trends of JAK inhibitors in the U.S. Medicaid program from 2011 to 2023, and identify prescribing patterns and cost implications.

Methods: A retrospective, descriptive analysis was conducted using CMS Medicaid State Drug Utilization Data from 2011 to 2023. The study included all FDA-approved JAK inhibitors reimbursed by Medicaid: Xeljanz, Rinvoq, Olumiant, Jakafi, Opzelura, Inrebic, Cibinqo, Litfulo, Oijjaara, and Sotyktu. Utilization was measured by total prescriptions per year, while spending was assessed based on total Medicaid reimbursements. Price per prescription and per unit were calculated by dividing total spending by the number of prescriptions and total units, respectively. Trends were analyzed to observe shifts in prescribing, spending, and pricing.

Results: JAK inhibitor utilization increased steadily, peaking in 2022 with a total of 173,038 prescriptions, before dropping to 151,210 prescriptions in 2023. Xeljanz and Rinvoq had the highest cumulative number of prescriptions from 2011–2023, reaching 617,743 and 120,820 prescriptions, respectively, while newer agents like Opzelura and Lifulo showed rapid uptake in 2022–2023, reaching 38,784 and 4,465 prescriptions in 2023, respectively. Medicaid spending mirrored utilization trends, with total reimbursement peaking in 2022 at approximately $420 million and dropping to $341 million in 2023. Xeljanz alone accounted for $161 million in total spending, followed by Rinvoq ($73 million) and Opzelura ($63 million). Prices per prescription and per unit increased across nearly all drugs. The steepest price increases were observed for Rinvoq (average price per prescription: $6,637; per unit: $255), Opzelura ($5,789; $209), and Lifulo ($3,851; $134), indicating potential influence of market exclusivity and manufacturer pricing strategies.

Conclusions: Use of JAK inhibitors in Medicaid increases while rising costs pose economic challenges. The decline in some drugs' utilization and spending in 2023 suggests shifting prescribing behaviors or policy adjustments. Given the persistent price increases, further research is needed to assess long-term affordability, equitable treatment availability, and cost containment strategies.