OUTCOMES OF AUTOLOGOUS TRANSPLANT, ALLOGENEIC TRANSPLANT, AND CAR T CELL THERAPY IN TP53 ALTERED MANTLE CELL LYMPHOMA: A MULTI‐INSTITUTION RETROSPECTIVE ANALYSIS

Introduction: TP53 alterations are associated with poor prognosis in mantle cell lymphoma (MCL). In trials of intensive chemotherapy and autologous hematopoietic transplant (auto-HCT), patients (pts) mutations had an overall survival (OS) 1.8 years (yrs) compared to 12.7 yrs for unmutated. Optimal treatment achieve durable remission is unknown. We report cellular therapy outcomes a large cohort pts altered MCL. Methods: conducted multi-site retrospective study MCL harboring mutation, deletion, or overexpression at 25 sites the United States from 1998 2022. For after auto-HCT, allogeneic (allo-HCT), chimeric antigen receptor T (CAR-T), alteration must have been present time this therapy. Event free (EFS) allo-HCT, CAR-T was defined as relapse, subsequent therapy, death. Results: identified 254 MCL, median 4.8 follow up baseline characteristics described table 1. found 75% diagnosis. OS total 6.3 There no difference based on type Ki-67. MIPI high risk (p < 0.0001) blastoid/pleomorphic variant = 0.02) predicted shorter OS. were 75 consolidative auto-HCT eligible pts, age 65 under events within 6 months first line Of these, 42 received remission. Median EFS 4.0 who 1.5 0.01). 1.0). Among 2.1 (N 10) 2.2 without 18) 0.5). Allo-HCT used 24 2 lines 46% prior Bruton tyrosine kinase inhibitor (BTKi) treatment. matched 74%, related donor 50%, myeloablative 25%, using post-transplant cyclophosphamide 46%, ATG 13%. With 5.9 yrs, allo-HCT 5.4 according alteration. 5 still over allo-HCT. 37 3 92% BTKi 86% bridging 1.3 0.9 1.4 Conclusion: Here we largest pooled analysis Within cohort, morphology even survival. Auto-HCT improved all altered, but not among mutated. do appear abrogate conferred by emphasizing need targeted clinical population. Keywords: aggressive B-cell non-Hodgkin lymphoma, therapies, stem Conflicts interests pertinent abstract S. D. Smith Consultant advisory role: Astrazeneca, Beigene, KITE pharma Research funding: Genentech Bond SeaGen, KITE/Gilead, Nurix Nurix, Novartis P. Ramakrishnan Geethakumari KITE, BMS, Rafael Pharma, Pharmacyclics LLC, ADC Therapeutics, Cellectar Biosciences, Ono Pharma