Chimeric Antigen Receptor T-Cell Access in Patients with Relapsed/Refractory Large B-Cell Lymphoma: Association of Access with Social Determinants of Health and Travel Time to Treatment Centers

Abstract

Large B-cell lymphoma (LBCL) is the most common type of non-Hodgkin lymphoma. Chimeric antigen receptor T-cell (CAR T) therapy represents a novel treatment with curative potential for relapsed or refractory (R/R) LBCL, but there are access barriers to this innovative therapy that are not well-studied. (1) Assess the impact of geographic factors and social determinants of health (SDOH) on access to treatment with CAR T in a sample of patients with R/R LBCL and ≥2 prior lines of treatment (LOT). (2) Compare and contrast patient characteristics, SDOH, and travel time between patients with R/R LBCL who received CAR T and those who did not. An observational, nested case-control study of patients with R/R LBCL, ≥2 prior LOT, not in a clinical trial, identified using 100% Medicare Fee-For-Service and national multi-payer claims databases. Patients were linked to near-neighborhood SDOH using 9-digit ZIP-code address. Driving distance and time between residence and nearest CAR T treatment center (TC) was calculated. Patients were stratified based on treatments received upon third LOT initiation (Index Date) or later: (1) received CAR T and (2) did not receive CAR T. Multivariable logistic regression was used to evaluate factors associated with CAR T. About 5011 patients met inclusion criteria, with 628 (12.5%) in the CAR T group. Regression models found the likelihood of receiving CAR T decreased with patient age (odds ratio [OR] = .96, P < .001), and males were 29% more likely to receive CAR T (OR = 1.29, P = .02). Likelihood of CAR T increased with Charlson Comorbidity Index (CCI; OR = 1.07, P < .001) indicating patients with more comorbidities were more likely to receive CAR T. Black patients were less than half as likely to receive CAR T than White patients (OR = .44, P = .01). Asian patients did not significantly differ from White patients (OR = 1.43, P = .24), and there was a trend for Hispanic patients to have a slightly lower likelihood of CAR T (OR = .50, P = .07). Higher household income was associated with receipt of CAR T, with the lowest income group more than 50% less likely to receive CAR T than the highest (OR = .44, P = .002), and the second lowest income group more than 30% less likely (OR = .68, P = .02). Finally, likelihood of CAR T therapy was reduced when the driving time to the nearest TC was 121 to 240 minutes (reference group: ≤30 minutes; OR = .64, P = .04). Travel times between 31 and 121 or greater than 240 minutes were not significantly different from ≤30 minutes. Payer type was collinear with age and could not be included in the regression analysis, but patients with commercial insurance were 1.5 to 3 times more likely to receive CAR T than other payers on an unadjusted basis. We identified significant disparities in access to CAR T related to demographics and SDOH. Patients who were older, female, low income, or Black were less likely to receive CAR T. The positive association of CCI with CAR T requires further research. Given the promising outcomes of CAR T, there is urgent need to address identified disparities and increase efforts to overcome access barriers.