Characteristics and Clinical Outcomes of Patients with Relapsed/Refractory Diffuse Large B-cell Lymphoma who Received at Least 3 Lines of Therapies

Abstract Introduction The treatment landscape for diffuse large B-cell lymphoma (DLBCL) has recently changed. We examined characteristics and clinical outcomes of DLBCL patients who initiated a third (3L) and fourth (4L) line of therapy during a contemporary time frame. Methods Adult patients diagnosed with DLBCL who received ≥3L after January 1, 2014 were selected from the COTA database. Patients were grouped into cohorts by 3L or 4L initiation and further stratified by type of treatment received: chemotherapy or chemoimmunotherapy (CT/CIT), targeted therapy (TT), chimeric antigen receptor T cells (CAR-T), or salvage therapy consolidated with hematopoietic cell transplant (HCT). Patient characteristics, response rates, and overall survival (OS) were examined. Results Among adult patients with relapsed/refractory (r/r) DLBCL, 212 (mean age; 61.8 years; 59.0% male) received their 3L and 127 (mean age: 61.0 years; 61.4% male) their 4L. Among those treated with their 3L and 4L, 55.2% and 50.4%, respectively, received CT/CIT; 26.9% and 34.6% received TT. The complete response rate of 3L patients was 9.4% for CT/CIT, 10.5% for TT, and 60% for CAR-T. Similar findings were seen with 4L patients (CT/CIT: 6.3%; TT: 15.9%; CAR-T: 53.8%). For those who received pharmacological treatment in 3L and 4L, median OS times were 7.7 and 4.4 months, respectively. Median OS times of patients who received cell-based therapies (CAR-T/HCT) were not reached. Conclusion In this study, a majority of r/r DLBCL patients were treated with CT/CIT or TT in 3L and 4L settings and had poor clinical outcomes, underscoring the need for more effective treatments. Microabstract Purpose: To examine outcomes of r/r DLBCL Methods: Retrospective study using COTA EHR database (2014-early 2020) Results: Majority of patients received pharmacological treatment in 3L and 4L; median OS times were 7.7 and 4.4 months, respectively. Conclusion: There is an unmet need for more effective r/r DLBCL treatments.