P-119: Evaluation of real-world frontline treatment for multiple myeloma by race

Abstract

<h3>Background</h3> African Americans (AA) are disproportionately affected by multiple myeloma (MM) with over double the incidence and mortality rates as compared to white patients. Although there have been significant therapeutic advances for the treatment of MM over the last 20 years, research has suggested that these benefits may not be uniform across racial groups. We sought to explore racial disparities in multiple myeloma using contemporary real-world data (RWD). <h3>Methods</h3> A total of 1790 patients meeting the study criteria were identified in the COTA real-world database, a de-identified database of RWD derived from the electronic health records of healthcare providers in the United States. Study eligibility criteria included active MM diagnosis after Jan. 1, 2015, and white (n=1494) or AA (n=296) race. Patient characteristics and treatment patterns were summarized by line of therapy (LOT). LOT was assigned programmatically on the retrospective RWD using an algorithm based on IMWG criteria and clinical guidance. Time to next treatment (TTNT) was calculated using the Kaplan-Meier method. <h3>Results</h3> In comparison to white patients, the AA cohort consisted of younger (median age 61.0 vs 66.0 yrs, p<0.001) and majority female patients (52.4% vs 40.9%, p<0.001). Both racial cohorts were predominately treated in the academic setting (AA: 68.9% vs white: 67.7%). AA patients had significantly longer median [IQR] time to first-line (1L) treatment (24.0 [10.0, 48.3] vs 19.0 [7.0, 36.0] days, p=0.002), as well as longer time to first stem-cell transplant (SCT) (218.0 [176.0, 322.5] vs 185.0 [145.0, 261.0] days, p<0.001). Overall, 1L treatment types were similar across racial cohorts; the most common 1L treatment was proteasome-inhibitor (PI) in combination with immunomodulator (imid) and steroids (AA: 41.6% and white: 42.4%). Similar proportions of patients received 1L SCT by racial group (13.9% and 15.9% among AA and white patients, respectively). Among patients that received 1L PI, differences were observed between types of 1L PI regimen, with a greater proportion of AA patients receiving bortezomib-based treatment (80.0% vs 71.3%) and lower proportion receiving carfilzomib-based treatment (16.9% vs 23.8%, p=0.03). No significant differences were observed between TTNT across racial and PI subgroups from 1L to 2L treatment. <h3>Conclusions</h3> These findings suggest that frontline treatment patterns were similar by race in a contemporary real-world cohort treated predominately in the academic setting. Despite delays in 1L therapy initiation among African American patients, TTNT from 1L to 2L were similar. Additional disparities were observed in testing rates for 1p deletion and tp53. Future analyses will investigate treatment patterns by practice setting and expand into later LOTs to further elucidate if academic practices and uniform treatment patterns drive similar outcomes by race.