Access to SGLT2 inhibitors (SGLT2i) and GLP-1 receptor agonists (GLP-1RA) may be limited by high drug prices and insurance related barriers including prior authorization or step therapy requirements. These barriers are particularly challenging for seniors covered under Medicare’s prescription drug benefit (Part D). We used Q1 2019 national Part D Formulary files to examine: 1) the proportion of plans (weighted by enrollment) that cover a SGLT2i or GLP-1RA without prior authorization or step therapy and 2) the average retail price [IQR] for a 30-day supply of each medication. Among 3,992 plans (enrolling at least 37,980,936 beneficiaries), weighted coverage without prior authorization or step therapy for canagliflozin, dapagliflozin and empagliflozin was 53.2% (95% CI: 49.1 to 57.4), 63.7% (95% CI: 60.1 to 67.3) and 95.4% (95% CI: 94.3 to 96.4), respectively. Coverage without prior authorization or step therapy for GLP-1RA of ranged from 3.2% (95% CI: 1.8 to 4.6) for lixisenatide to a high of 87.4% (95% CI: 85.5 to 89.3) for dulaglutide. The mean retail price [IQR] for a 30-day supply of a SGLT2i or a GLP-1RA ranged from $295 [$285-$303] (ertugliflozin) to $512 [$501-$527] (canagliflozin) and $641.38 [$629-$657] (lixisenatide) to $946.17 [$930-$968] (liraglutide), respectively. In 2019, coverage without prior authorization and step therapy for SGLT2i and GLP-1RA were mixed across Part D plans. Most beneficiaries enrolled in plans that covered at least one SGLT2i and one GLP-1RA without restrictions. Cost sharing (i.e., high out-of-pocket payments) may be more problematic for patients than either prior authorization or step therapy.


J. Luo: Consultant; Self; Alosa Health. R. Feldman: None. S.D. Rothenberger: None. W.F. Gellad: None.


National Center for Advancing Translational Sciences (KL2TR001856)

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