P150 | OUTCOMES AFTER CD19-DIRECTED CHIMERIC ANTIGEN RECEPTOR T CELLS FOR B-CELL MALIGNANCIES: A SINGLE CENTER EXPERIENCE.

Introduction. Chimeric antigen receptor T-cells (CART) have revolutionized B-cell malignancies treatment. Their toxicities include cytokine release syndrome (CRS) and neurologic events (NE). Many real-life data confirm these toxicities reporting lower incidences of severe forms. Methods. We report our single center experience with commercially available CART targeting CD19. Patients’ eligibility was assessed according to AIFA criteria for each commercial CART. Results. Ninety-two patients have been evaluated from November 2021 to January 2025, with 29 (32%) not fulfilling AIFA criteria. The remaining 63 (68%) underwent apheresis. The distribution of collected CART products was as follows: axicel (2L DLBCL, n=10; ≥3L DLBCL, n=17; PMBCL, n=3; FL, n=1), brexucel (MCL, n=7; B-ALL, n=4); tisacel (≥3L DLBCL, n=13; FL, n=7; B-ALL, n=1). Thirty-eight patients (60%) received a bridge therapy prior to CART cell infusion (R-polatuzumab-bendamustine, n=15; R-polatuzumab, n=4; R-lenalidomide, n=3; R-gemcitabine-cisplatin, n=3; other, n=13). Infusion was not possible in 10 (16%) patients experiencing progressive disease. One patient suddenly died due to unknown causes. Globally, 52 (84%) CART were infused (axicel: 2L DLBCL, n=10; ≥3L DLBCL, n=12; PMBCL, n=2; FL, n=1; brexucel: MCL, n=5; B-ALL, n=4; tisacel: ≥3L DLBCL, n=11; FL, n=6; B-ALL, n=1). One patient with FL and PD died 2 days after infusion due to a fatal post-traumatic hemorrhage and was thus excluded for the post-infusion analysis. The infused cohort included 26 (51%) males and 25 (49%) females with a median age of 59 (range 22-83) years. Four patients received an out-of-specification product. Median time from apheresis to CART shipment was 28 (range 16-54) days. Median time from shipment to infusion was 31 (range 5-122) days. Disease status prior to infusion was: stable disease, n=25; PD, n=6; partial remission, n=17; complete remission, n=3). Forty-four (86%) patients developed CRS, all grades 1-2. Four patients (8%) developed grade 2-3 NE. One patient (2%) developed macrophage activation syndrome successfully treated with steroids and anakinra. Tocilizumab was used in 22 (43%) and steroids in 12 (24%) patients. None needed transfer to intensive care unit (ICU). Median duration of hospitalization was 19 (range 9-36) days. At last follow-up 10 patients died, 8 due to disease relapse (including 2 CD19-negative relapses), 1 after developing a TP53 mutated myelodysplastic syndrome, 1 due to unknown causes. With a median follow-up of 9 (range 1-31) months, 6-months PFS and OS were 77%±6 and 89%±5, respectively. Conclusion. Our results align with other reports of real-life experiences with CART. Despite being frequent, short-term toxicities are reversible and can be managed without need of transfer to ICU. Secondary malignancies and CD19-negative relapses remain major concerns with the use of CART.