Ruchika Talwar

PURPOSE Self-administered oncology drugs contribute disproportionately to Medicare Part D spending; prices often remain high even after generic entry. Outlets for low-cost drugs such as Mark Cuban Cost Plus Drug Company (MCCPDC) offer opportunities for decreased Medicare, Part D, and beneficiary spending. We estimate potential savings if Part D plans obtained prices such as those offered under the MCCPDC for seven generic oncology drugs. METHODS Using the 2020 Medicare Part D Spending dashboard, Q3-2022 Part D formulary prices, and Q3-2022 MCCPDC prices for seven self-administered generic oncology drugs, we estimated Medicare savings by replacing Q3-2022 Part D unit costs with costs under the MCCPDC plan. RESULTS We estimate potential savings of $661.8 million (M) US dollars (USD; 78.8%) for the seven oncology drugs studied. Total savings ranged from $228.1M USD (56.1%) to $2,154.5M USD (92.4%) compared with 25th and 75th percentiles of Part D plan unit prices. The median savings replacing Part D plan prices were abiraterone $338.0M USD, anastrozole $1.2M USD, imatinib 100 mg $15.6M USD, imatinib 400 mg $212.0M USD, letrozole $1.9M USD, methotrexate $26.7M USD, raloxifene $63.8M USD, and tamoxifen $2.6M USD. All 30-day prescription drug prices offered by MCCPDC generated cost savings except for three drugs offered at the 25th percentile Part D formulary pricing: anastrozole, letrozole, and tamoxifen. CONCLUSION Replacing current Part D median formulary prices with MCCPDC pricing could yield significant savings for seven generic oncology drugs. Individual beneficiaries could save nearly $25,200 USD per year for abiraterone or between $17,500 USD and $20,500 USD for imatinib. Notably, Part D cash-pay prices for abiraterone and imatinib under the catastrophic phase of coverage were still more expensive than baseline MCCPDC prices.