Prognostic factors and outcomes of tisagenlecleucel in relapsed or refractory B-cell malignancies: a single-center real-world study.

[BACKGROUND] Tisagenlecleucel (tisa-cel), a CD19-targeted chimeric antigen receptor T-cell (CAR-T) therapy, is an approved treatment for relapsed or refractory (R/R) diffuse large B-cell lymphoma (DLBCL) and B-cell precursor acute lymphoblastic leukemia (B-ALL). While pivotal trials demonstrated its efficacy, real-world evidence from Asian populations remains scarce. In particular, data on manufacturing feasibility, clinical outcomes, and predictive biomarkers in Korean patients are limited.

[OBJECTIVE] This study aimed to evaluate the clinical outcomes and prognostic factors of tisa-cel therapy in Korean patients with R/R DLBCL and B-ALL, with a specific focus on apheresis product quality and baseline immune markers.

[STUDY DESIGN] A single-center retrospective study was conducted including 91 patients (DLBCL = 72; B-ALL = 19) intended to receive tisa-cel between April 2022 and April 2024. Apheresis data, treatment responses, survival outcomes, and toxicity profiles were analyzed. The intention-to-treat (ITT) cohort was defined from the time of apheresis. Cox regression was used to identify predictors of survival and relapse, and separate analyses were performed for DLBCL and B-ALL.

[RESULTS] Out of 91 patients, 72 received tisa-cel infusion. One-year overall survival (OS) and disease-free survival (DFS) for the entire ITT cohort were 45.9% and 37.5%, respectively. In 19 B-ALL after tisa-cel infusion, 1-year OS and DFS were 68.4% and 52.6%, with no non-relapse mortality (NRM). In 53 DLBCL after tisa-cel infusion, 1-year OS and DFS were 46.8% and 41.6%, respectively, with 29.6% cumulative incidence of relapse among responders. NRM was 9.5% mostly observed in elderly patients. In the DLBCL subgroup, poor OS was independently associated with third-or-later-line salvage therapy (hazard ratio [HR] 2.39), high peripheral blood monocyte proportion at apheresis (>10%, HR 2.57), low CD3+ T-cell concentration in apheresis product (<1.0×10⁸/mL, HR 4.31), and occurrence of immune effector cell-associated neurotoxicity syndrome (HR 2.47). B-ALL patients demonstrated favorable survival and lower toxicity, but no significant prognostic markers were identified.

[CONCLUSIONS] Tisa-cel therapy was feasible and effective in Korean patients with R/R B-cell malignancies. Pre-treatment immune parameters such as monocyte burden and CD3+ T-cell quality in apheresis products significantly influenced outcomes in DLBCL. These findings suggest that optimizing patient selection and refining manufacturing strategies may enhance CAR-T efficacy, particularly in resource-constrained or heterogeneous real-world settings.