Costs and access barriers to ondansetron: A national analysis of Medicare part D and Medicare Advantage plans.

Abstract

e23126 Background: Seniors living with cancer and receiving prescription drug benefits through Medicare Part D Prescription Drug Plans (PDPs) can face cost and access barriers in the forms of prior authorization and quantity limit policies. While over half of Medicare beneficiaries are now insured with drug benefits through Medicare Advantage, it remains unclear how costs and access barriers compare between PDPs and MA drug plans (MADPs). This study compared plan-level costs and prevalence of prior authorization or quantity limit policies between PDPs and MADPs for oral ondansetron, an essential and widely used antiemetic for patients with cancer. Methods: We used 2023 Q3 MA and PDP data from the Center for Medicare and Medicaid Services, excluding employer-sponsored and Supplemental Need Plans (including dual-eligible plans) and plans with < 10 enrollees. We focused on the four most common generic ondansetron forms: 4mg and 8mg tablets, and 4mg and 8mg orally disintegrating tablets (ODT). To compare medication quantities, we calculated the median (IQR) cost of 30-day supply (90 dosage units), defining plan-level price as the average unit cost for each formulation. Price benchmarks were defined using Mark Cuban Cost-plus Drug Company cash prices, which reflect fixed markup to negotiated wholesale prices. T-test and Chi-square tests were used for comparison. Results: Across 813 PDPs and 3512 MADPs, MAPDs had lower median costs for a 30-day supply of ondansetron than PDP plans (4mg tab: $16.1 vs $29.2; 4mg ODT: $38.0 vs $56.4; 8mg tab: $24.7 vs $35.6; 8mg ODT: $37.2 vs $54.4, all p < 0.01). Median costs for both PDPs and MAPDs were higher than benchmarks (66-155% across formulations; all p < 0.01). PDPs and MAPDs had similarly high prior authorization rates (83.6% vs 83.4%, p = 0.89), but MAPDs used quantity limits more frequently (22.5% vs 16.5%, p < 0.01). There was little variation in prior authorization and quantity limit policies across formulations. Conclusions: Ondansetron costs in both PDPs and MAPDs were higher than benchmarks. Compared to PDPs, MAPDs offered ondansetron at lower costs but used policies creating access barriers for patients either at similar (prior authorization) or higher (quantity limit) frequency, burdening patients, physicians, health systems, and pharmacies. [Table: see text]