16 Background: The Oncology Care Model (OCM) was a 6-year long Medicare value-based care (VBC) program that rewarded practices for maintaining high-quality cancer care, while decreasing the total cost of care (TCOC) compared to a benchmark price. Lenalidomide, an oral medication used to treat multiple myeloma and other hematologic cancers, had the highest total Part D spending in the OCM. Lenalidomide is available as capsules of multiple strengths (2.5mg, 5mg, 10mg, 15mg, 20mg and 25mg), having the same cost per pill (mean cost of $735 per pill (over the 6 years)) for each of the strengths. Standard lenalidomide dosing includes one of the dose strengths taken once daily for 21 days on a 28-day cycle, 14 days on a 21-day cycle, or 28 days on a 28-day cycle. Doses and schedules may be adjusted to account for patient toxicities, different indications, or individual preferences. We studied the impact of different dosing approaches for Lenalidomide on TCOC. Methods: We used Medicare prescription dispense data for Lenalidomide for 15 practices in The US Oncology Network (The Network), participating in the OCM. We grouped dispenses based on pills per day (calculated using count of pills dispensed & days' supply), and evaluated the prevalence of different dosing approaches, cost of Lenalidomide, and the impact on TCOC throughout the OCM time periods (July 2016 to June 2022). Results: 85.5% of 52,793 total dispenses were for one pill daily doses, 10% (5,281) for fewer than one pill daily doses, and 4.5% (2,377) for alternative dosing approaches using more than one pill per day, such as multiple pills taken once daily, one pill taken more frequently than once daily, or the total strength being dispensed as a combination of multiple smaller strengths. Alternative dosing approaches led to a mean total cost of $28,300 per dispense, versus $15,600 per dispense for one pill daily doses. 95% of the episodes with alternative dosing approaches had TCOC more than the benchmark, whereas only 52% of the episodes with one pill daily dosing had TCOC more than the benchmark. Total strengths of Lenalidomide dispensed as a combination of multiple smaller strengths had the highest mean total cost of all alternative dosing approaches. Conclusions: Dosing approaches utilizing more than one pill per day for oral medications like Lenalidomide can lead to significantly higher total cost and unfavorable VBC outcomes. Similar impacts may be found with other oral medications where per pill costs are high. Appropriate dosing strategies for optimizing pill counts of oral medications can lead to cost savings for patients, and the health system at large.