Scope and characteristics of patients filling medications through specialty pharmacies by ownership type

Introduction: Arkansas recently prohibited pharmacy ownership by pharmacy benefit managers (PBMs), with similar proposals emerging nationally. Little evidence describes which patients rely on specialty pharmacies by ownership type or how divestiture policies may affect access. Methods: Using Colorado all-payer claims linked to National Council for Prescription Drug Programs pharmacy information, we identified specialty pharmacy users among all patients' insurance coverage. Pharmacies were categorized as PBM-owned, insurer-owned, or non-vertically integrated. Patient demographics, Social Vulnerability Index (SVI) scores, and prescription utilization were compared across groups. Results: Among eligible patients, 0.8% used a specialty pharmacy. Specialty pharmacy users were older, more often female, with higher SVI scores and greater prescription utilization. Vertically integrated specialty pharmacies accounted for a substantial share of fills, and their users exhibited higher social vulnerability and greater medication needs compared with users of nonintegrated pharmacies. Conclusion: Specialty pharmacy users disproportionately include more vulnerable individuals with complex therapy needs. Legislation banning PBM or insurer ownership of specialty pharmacies may disrupt access for these high-need groups, underscoring the need for careful policy design.