Trends and Factors Associated With Insurer Approval of Proprotein Convertase Subtilisin/Kexin Type 9 Inhibitor Prescriptions.

ABSTRACT

OBJECTIVES: Proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9is)-innovative yet costly cholesterol-lowering agents-have been subject to substantial prior authorization (PA) requirements and low approval rates. We aimed to investigate trends in insurer approval and reasons for rejection for PCSK9i prescriptions as well as associations between patients' demographic, clinical, pharmacy, payer, and PCSK9i-specific plan/coverage factors and approval. METHODS: We examined trends in PCSK9i approval rates and reasons for rejection using medical and prescription claims from 2015 to 2017 for individuals who received a PCSK9i prescription. We used multinomial logistic regression to estimate quarterly risk-adjusted approval rates for initial PCSK9i prescriptions and approval for any PCSK9i prescription within 30, 90, and 180 days of the initial PCSK9i prescription. For a 2016 subsample for whom we had PCSK9i-specific plan policy data, we examined factors associated with approval including PCSK9i-specific plan formulary coverage, step therapy requirements, and number of PA criteria. RESULTS: The main sample included 12 309 patients (mean age 64.8 years [SD = 10.8], 52.1% female, 51.5% receiving Medicare) and was similar in characteristics to the 2016 subsample (n = 6091). Approval rates varied across quarters but remained low (initial prescription, 13%-23%; within 90 days, 28%-44%). Over time, rejections owing to a lack of formulary coverage decreased and rejections owing to PA requirements increased. Lack of formulary coverage and having ≥11 PA criteria in the plan policy were associated with lower odds of PCSK9i prescription approval. CONCLUSIONS: These findings confirm ongoing PCSK9i access issues and offer a baseline for comparison in future studies examining the impact of recent efforts to improve PCSK9i access.