Tailored doses, tailored savings: Optimizing dosing strategies of immune checkpoint inhibitors.

68 Background: While immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment, their high cost and limited global supply pose major challenges. Optimizing ICI dosing to achieve a minimum effective dose that has shown to maintain clinical benefit may be a potential solution with significant savings to the health system. We investigated potential savings in Medicare that could be attained from alternative ICI dosing. Methods: We conducted a literature review including original Phase 1/2 trials describing the minimal effective dose of three commonly used ICIs: Pembrolizumab (P), Nivolumab (N) and Atezolizumab (A). Alternate dosing strategies based on existing data for Pembrolizumab (2 mg/kg), Nivolumab (1 mg/kg) and Atezolizumab (4 mg/kg) were proposed. Publicly available CMS data on Medicare Part B expenditure for these therapies was utilized to obtain average cost per dosage unit, mg/dosage unit, and number of Medicare beneficiaries between 2018-2021. Average cost per dose and total cost per ICI was calculated based on current FDA approved dosing and alternate dosing strategies. Results: The average wholesale cost per fixed dose for P (200 mg), N (480 mg), and A were $9,242.00, $12,460.80, and $8,616.00, respectively. Implementing the proposed alternate dosing strategies led to a substantial reduction in drug costs: P ($7,393.60), N ($2,076.80), and A ($2,297.60). The ensuing cost savings were calculated based on the annual number of Medicare beneficiaries. From 2018-2021, the average total savings were estimated to be $95,545,182 for Pembrolizumab, $294,734,264 for Nivolumab, and $62,937,582 for Atezolizumab (Table). The cumulative average total cost savings from 2018-2021 exceeded $453 million. Conclusions: We demonstrate potential savings in Medicare with implementation of an alternative ICI dosing strategy. Our study underscores an urgent need to better understand clinical efficacy and cost savings from a patient perspective, and feasibility from a regulatory standpoint. This perspective may hold considerable global implications, providing a roadmap for cost-effective care in the domain of immunotherapy. [Table: see text]