ABCL-102 A SEER-Medicare Analysis of the Cost of Disease Progression After Frontline R-CHOP in Diffuse Large B-Cell Lymphoma

Abstract

Subsequent therapies for relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL) are associated with substantial treatment costs. Previous studies are outdated and exclude novel therapies, including chimeric antigen receptor T-cell therapy (CAR-T). To understand the economic burden associated with disease progression in DLBCL. This retrospective cohort study used Surveillance, Epidemiology, and End Results (SEER) cancer registry data linked with Medicare claims data (2010-2017). Mean follow-up was 45 months. Patients with DLBCL received frontline (1L) therapy with R-CHOP. End of therapy was defined as a gap of ≥60 days or initiation of new agents. Patients not receiving second-line (2L) treatment for ≥2 years were assigned to the "no progression" cohort, and those receiving non-R-CHOP therapy after 1L therapy to the "progression" cohort. The index date was defined as either 60 days after the end of 1L treatment or initiation of 2L treatment. All-cause healthcare costs per-patient-per-month (PPPM) were compared between cohorts. Generalized linear models were used to adjust for baseline characteristics, including age, sex, US region, race, urban/rural status, marital status, income, education, Ann Arbor stage, Charlson Comorbidity Index (CCI), and healthcare costs 1 year before the index date. Overall, 4,573 patients were identified (no progression: n=3,712 [82.2%]; progression: n=861 [18.8%]). Overall cohort characteristics included female, 51%; mean [SD] age, 76.4 [6.4] years; CCI [non-cancer] at index, 2.9 [2.4]. In the progression cohort, 390 patients (45.3%) had multiple relapse events, and 122 (14.2%) and 14 (0.02%) received stem cell transplant (SCT) and CAR-T, respectively. Mean PPPM cost was higher among progressors than non-progressors (unadjusted: $13,880 vs. $4,406; adjusted: $14,322 vs. $4,404; P<0.001). The major cost component was inpatient cost (39.0% and 53.8% of total cost for progressors and non-progressors, respectively). Treatments including cellular therapy were associated with increased cost (unadjusted: $14,847 [SCT], $28,152 [CAR-T] vs. $4,406 [no progression]). The cost of disease progression in DLBCL is considerable, particularly among Medicare patients receiving novel treatments as later lines of therapy. Future use of CAR-T in earlier lines may increase the cost of disease progression further. Effective 1L treatments for DLBCL could reduce the economic burden associated with disease progression.