Abstract 3194: Opposing roles of product CD27 and TIGIT expression in outcome to CAR-T cell therapy in R/R LBCL

Background: CAR-T cell therapy provides transformative outcomes for patients with relapsed/refractory (R/R) large B cell lymphoma (LBCL). However, a large fraction of patients remains at risk for relapse, underlying the need to uncover mechanisms of resistance and predictive biomarkers. We leveraged ZUMA-1, -6 and -7 studies of R/R LBCL to discover product features associated with outcome to CAR-T cell therapy [Axicabtagene Ciloleucel (axi-cel)]. We explored ligand-receptor interactions between product cells and the tumor microenvironment, identifying CD27-CD70 and TIGIT-PVR axes as putative mediators of durable response and disease progression, respectively. Methods: Cytometry by time of flight (CyTOF) with 34 markers pertinent to T cell phenotyping and activation was performed on CAR-T cell products from ZUMA-1 (3rd line(L) LBCL; n = 57), ZUMA-6 (CAR-T cells + Atezolizumab; 3rd L LBCL; n = 14), and ZUMA-7 (2nd L LBCL; n = 45). Individual marker intensity and unsupervised clustering (by flowSOM algorithm) analysis were performed to identify features associated with outcome and a P-value < 0.05 was considered significant by descriptive statistics. The CyTOF analysis was combined with transcriptomic Nanostring IO360™ from ZUMA-7 pre-infusion tumors (N=35) for ligand-receptor interaction studies. scRNAseq analysis was performed (CellRanger v7.0 and Scanpy) on a set of ZUMA-1 products (n=36). Results: Cross-study analysis of individual CyTOF markers presented increased expression of activation and exhaustion proteins CD29, OX40 and TIGIT in patients who experienced disease progression (lack of response or relapse after response), while co-stimulatory CD27 and NKG2D associated with ongoing response (P < 0.05). Unsupervised clustering analysis demonstrated that product CD8 stem central memory (T-SCM) cells, expressing CCR7, CD45RA, CD95, NKG2D, and CD27 associated with ongoing response (P < 0.01), while activated memory or senescent CD4+ cells associated with disease progression (P < 0.05). All patients with > 25% CD8 T-SCM (% of T cells) responded to axi-cel (100% ORR), with TIGIT expression representing the only marker significantly associated with Relapse Vs Ongoing response status in these patients (P < 0.05). The analysis of receptor expression on product cells Vs ligand expression in the tumor uncovered associations of the CD27-CD70 and TIGIT-PVR axes with durable response and disease progression, respectively. scRNAseq of ZUMA-1 products corroborated the above observations, with elevated TIGIT expression in two cell clusters enriched in non-responding patients. Conclusions: Using orthogonal methods on three clinical studies, we identified product features consistently associated with CAR T-cell efficacy in r/r LBCL, informing design of next-generation products and combinatorial approaches to improve outcome, including product enrichment of CD27+ CD8 T-SCM and TIGIT inhibition. Citation Format: Justin Budka, Subing Cao, Chad Williams, Gabriela Balderrama-Gutierrez, Soumya Poddar, Mike Mattie, Jenny J. Kim, Saran Vardhanabhuti, Yohei Arihara, Yusuke Kamihara, Shogo Miura, Jerome Ritz, Davide Bedognetti, Simone Filosto. Opposing roles of product CD27 and TIGIT expression in outcome to CAR-T cell therapy in R/R LBCL [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 3194.