P040 | REAL-WORLD EXPERIENCE WITH BISPECIFIC ANTIBODY EPCORITAMAB IN RELAPSED/REFRACTORY DLBCL: A MULTICENTRIC RETROSPECTIVE ANALYSIS

Background: Epcoritamab is approved for relapsed/refractory DLBCL from the third line onward. Pivotal trial results showed high efficacy and good safety. However, real-world data are limited, with some studies showing less favorable outcomes. This retrospective analysis evaluates its efficacy and safety in clinical practice. Methods: patients (pts) who received Epcoritamab between April 2024 and April 2025 were included. Clinical and disease data were collected from medical records. Primary endpoints were overall response rate (ORR) including complete and partial responses (CR, PR), progression-free survival (PFS) and overall survival (OS). The rate of Cytokine Release syndrome (CRS), Immune Effector Cell-associated Neurotoxicity Syndrome (ICANS) and infections was also recorded. Results: 22 pts were included. Baseline characteristics are summarized in Table 1. Most had advanced disease: 73% were stage IV, 86% had elevated LDH, 73% had bulky disease and 68% had an IPI score ≥3. Median prior treatments were 2 (range: 2–4); 73% received 2 lines, and 91% were primary refractory or relapsed within 12 months. 82% were refractory to two lines, and 95% relapsed or were refractory within 6 months of the last therapy. A majority of pts (n=13, 60%) progressed after CAR T-cell, 12/13 (92%) with early progression (<6 months). Median Epcoritamab cycles were 3.5 (range:0.5–11). Pts evaluable for response were 18/22 (82%) and 4/22 (18%) are awaiting evaluation. The ORR was 33% with 3 (17%) CR, 3 (17%) PR and 12 (66%) progressive disease (PD). Median follow-up: 7 months; median PFS and OS were 3 (95% CI 2-NR) and 6 months (95% CI 3-NR) respectively. CRS occurred in 9 pts (41%), with 1 G3 (4.5%). No ICANS cases. Infections occurred in 3/22 pts (13.6%), including 2 asymptomatic COVID-19 and 1 CMV pneumonia. No treatment discontinuation due to adverse events. Seven pts planned for allogenic transplant; one underwent the procedure. At the last follow-up, 13/22 pts (59%) were alive and 9/13 (69%) were still receiving Epcoritamab. Cause of death were PD in 8/9 (88%) and an allotransplant’s complication in one pts. Conclusions: In this real-world study of patients with unfavorable clinical characteristics, ORR, PFS, and OS were lower than in clinical trials. Epcoritamab was safe with manageable toxicities. Our experience highlights the need to better define disease and clinical factors to identify patients who could benefit most from Epcoritamab.