Psoriasis drugs in the medicare population: dermatologists' spending and prescription patterns.

PURPOSE: Over the past decade, many new biologic and small-molecule drugs have been approved for psoriasis. These specialty drugs tend to be expensive and place financial burden on the healthcare system as well as patients. This study aims to explore trends in Medicare Part D spending and prescription patterns for psoriasis drugs by dermatologists. METHODS: The Centers for Medicare and Medicaid Services' (CMS) Medicare Part D Public Use Files from 2013 to 2017 were utilized to examine prescription rates and pricing FDA-approved psoriasis drugs. RESULTS: From 2013 to 2017, psoriasis drugs accounted for 41% of total Medicare Part D spending by dermatologists in the database, of which biologics accounted for 86.5%. The proportion of psoriasis-related spending increased from 36% of total spending in 2013 to 53% in 2017. Prescriptions of etanercept decreased while prescribers of newly approved drugs increased significantly. The cost per day of biologics were significantly variable in 2013 but converged toward similar costs in 2017. CONCLUSION: Psoriasis prescriptions comprise a large, increasing proportion of Medicare Part D spending related to dermatology. These increasing costs have significant implications for the healthcare system and affect out-of-pocket costs for patients who rely on such medications.