Average percentage of covered insulins with UM tool per plan, combinations and concentrates: 2020–2025. The concentrates category includes insulin regular (Humulin R U-500). The combinations category contains insulin degludec/liraglutide (Xultophy) and insulin glargine/lixisenatide (Soliqua). Abbreviations: MAPD, Medicare Advantage Prescription Drug Plan; PDP, Prescription Drug Plan; UM, utilization management. Source: Authors' analysis of Part D plan formulary data.