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. MATERIALS AND 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.