Abstract A050: Evaluation of the effect of Medicare’s Oncology Care Model on racial disparities in patient receipt of novel cancer therapies
Authors: Manz Christopher R. , Tramontano Angela C. , Uno Hajime , Parikh Ravi B. , Bekelman Justin E. , Schrag Deborah 
Published: January 2023

Abstract
Introduction. Medicare’s Oncology Care Model (OCM) was a demonstration project that tied performance-based payments to cost and quality goals for participating oncology practices. A major concern about OCM regarded inclusion of high-cost cancer therapies which could potentially disincentivize oncologists from prescribing novel therapies and could exacerbate racial disparities in access to novel cancer technologies. Methods: This retrospective cohort study used SEER-Medicare data to identify patients who were eligible to receive one of 10 novel cancer therapies that received FDA approval in the 18 months leading up to implementation of OCM. The difference-in-differences cohort analysis matched patients treated by OCM-participating oncologists to non-OCM-participating oncologists and used a multivariable mixed effects regression model to evaluate whether OCM participation changed the likelihood that patients received novel therapies versus alternative treatments. A pre-planned triple difference-in-difference-in-differences analysis evaluated the impact of OCM on Black/White racial disparities in receipt of novel therapies. Results. The study included 2,839 matched patients (760 OCM, 2,079 non-OCM) who had a median age of 73 years and were 56% female, 85% White, 8% Black and 94% non-Hispanic. Among non-OCM patients, 33.2% and 39.9% received novel therapies before and after the start of OCM, respectively, vs 40.1% and 50.3% for OCM patients (adjusted difference-in-differences: 3.5 percentage points [95% CI -3.7 – 10.7 percentage points, p=0.34]). Overall, Black patients were 39% less likely to receive novel therapies compared to White patients (OR 0.61, 95% CI 0.42-0.89, p&lt;0.01). Among patients of OCM clinicians, Black patients saw a larger increase in receipt of novel therapies after OCM implementation (27.8% pre-OCM to 54.1% post-OCM) compared to White patients (40.8% pre-OCM to 49.9% post-OCM) that erased the pre-OCM disparity. In contrast, among patients of non-OCM clinicians, Black patients saw a smaller increase in receipt of novel therapies (25.8% pre-OCM to 29.0% post-OCM) after OCM implementation than White patients (33.7% pre-OCM to 41.1% post-OCM). The difference-in-difference estimate for the effect of OCM was 23.0 percentage points (95% CI -2.4 – 48.5, p=0.08) for Black patients versus 1.8 percentage points (95% CI -6.0 – 9.5, p =0.66) for White patients. The triple difference-in-difference-in-differences analysis showed a large but not statistically-significant effect of OCM on this Black/White racial disparity (triple differences: 21.2 percentage points, 95% CI -5.5 – 48.0; p=0.12).Conclusion. OCM did not negatively affect patient receipt of novel therapies. OCM clinicians eliminated Black/White racial disparities in receipt of novel therapies after OCM implementation while non-OCM clinicians had an increase in this disparity. This triple-differences comparison was not statistically significant but had limited power – future analyses should evaluate the impact of payment models on disparities in receipt of novel therapies.
Citation Format: Christopher R. Manz, Angela C. Tramontano, Hajime Uno, Ravi B. Parikh, Justin E. Bekelman, Deborah Schrag. Evaluation of the effect of Medicare’s Oncology Care Model on racial disparities in patient receipt of novel cancer therapies [abstract]. In: Proceedings of the 15th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2022 Sep 16-19; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr A050.