Braunschweig, Ira

3025 Background: Axi-cel is an autologous anti-CD19 CAR T cell therapy. ZUMA-1 is a multicenter, registrational trial of axi-cel in patients (pts) with refractory/aggressive B-cell non-Hodgkin lymphoma (NHL). In a pre-specified interim analysis, ZUMA-1 met its primary endpoint with 76% objective response rate and 47% complete response (Blood 2016;128:LBA-6). We describe, for the first time, a tumor microenvironment immune gene signature associated with CAR T cell treatment (tx) of NHL pts. Methods: Paired biopsies, pre- and within 3 weeks post-axi-cel tx, were analyzed by digital gene expression followed by a pre-specified bioinformatics algorithm applied to IGES15 and IGES21 genes involved in immune-mediated tumor regression (Immunosign; Galon Immunity 2013). Immunosign profiles expression of a pre-defined set of effector T cell, Th1, chemokine, and cytokine genes. Expression analysis and hierarchical clustering were used to define an axi-cel-related tumor immune gene signature. Wilcoxon signed rank test with multiple test correction by FDR (Benjamini-Yekutieli) was used. Results: Gene expression profile comparisons of pre- and post-axi-cel tx biopsies from 14 pts showed profound changes in gene expression within the tumor environment after infusion. The most upregulated genes post-axi-cel tx were CCL5 (RANTES), CTLA4, and GZMA (log2 fold change > 2, P< 0.05, FDR < 0.050). Immune checkpoints PD-L1 and LAG3 were also upregulated post-axi-cel (log2 fold change > 1.6, P< 0.05, FDR < 0.055). Other genes associated with T cell proliferation, homing, and effector function were also upregulated: IL-15, GZMK, CXC3CL1 (Fractalkine), CD8A, and STAT4 (log2 fold change > 1.6; P< 0.05, FDR < 0.074). Additional baseline tumor characteristics and associative analysis will be presented. Conclusions: We define a mechanistic tumor immune gene signature in NHL pts associated with axi-cel tx. This signature comprises upregulation of T cell activation, effector, chemokine, and immune checkpoint genes. These data will potentially lead to rational optimization of T cell interventions in cancer Clinical trial information: NCT02348216.

3023 Background: Axi-cel (formerly KTE-C19) is an autologous anti-CD19 chimeric antigen receptor (CAR) T cell therapy. ZUMA-1 is a multicenter, registrational trial of axi-cel in patients (pts) with refractory aggressive non-Hodgkin lymphoma. In a prespecified interim analysis, ZUMA-1 met its primary endpoint, with a 76% objective response rate and a 47% complete response rate ( Blood 2016;128:LBA-6). Post-treatment CAR T cell blood levels were associated with objective response. Here, we describe novel associations between product characteristics and CAR T cell levels in pts. Methods: CAR T cell characteristics in axi-cel produced from 62 pts were analyzed by flow cytometry and modeled against CAR T cell levels. In vivo CAR T cell levels were measured by qPCR. T cell expansion during production (fold expansion/total days in culture) was compared with CAR T cell blood levels, using a partition analysis with expansion rates of ≥1 vs < 1. Wilcoxon 2-sample test and linear regression were used. Results: Axi-cel contained CCR7+ T cells (median, 42%; range, 15–73%), with naïve (CD45RA+/CCR7+; median, 12%; range, 1–57%), central memory (CD45RA−/CCR7+; median, 29%; range, 12–49%) phenotypes, and more differentiated CCR7− effector memory and effector T cells. On infusion, CAR T cells expanded rapidly, reaching peak levels within 2 weeks (median, 43 cells/μL; range, 1–1513), and were also measurable in all pts at 1 month (median, 2 cells/μL; range, 0.03–89). The CCR7+/CCR7− T cell ratio in axi-cel associated positively with peak ( P =0.001) and cumulative ( P =0.003) CAR T cell levels through 1 month. Axi-cel lots that expanded more rapidly during production (≥1.0-fold/d; n = 18/62) associated with higher cumulative levels of CAR T cells ( P =0.03). Other product characteristics, eg, CD4/CD8 ratio or number of infused T cells, were not significantly associated with CAR T cell blood levels. Conclusions: An association was observed between CAR T cell expansion in vivo and both the T cell growth rate during production and product cell phenotype pretreatment. A key attribute of axi-cel product was the presence of CCR7+ naïve/central memory T cells, without upfront T cell subset selection. Clinical trial information: NCT02348216.

Abstract Introduction: Axicabtagene ciloleucel (axi-cel) is an autologous anti-CD19 chimeric antigen receptor (CAR) T cell therapy. ZUMA-1 is a multicenter registrational trial of axi-cel in patients with refractory, aggressive B-cell non-Hodgkin lymphoma. In a pre-specified interim analysis, ZUMA-1 met its primary endpoint with a 76% objective response rate and 47% complete response. The incidence of Grade 3 and higher (Gr 3+) cytokine release syndrome (CRS) and neurologic events (NE) was 13% and 29%, respectively, in 93 patients with 1 month follow-up (Neelapu ASH 2016). We present novel immune signatures of Gr 3+ CRS and NE by analyzing the axi-cel-related biomarker profile in association with clinical outcomes. Methods: In this interim analysis of 62 patients, 44 serum analytes pre- and post-axi-cel treatment were measured via ELISA at multiple timepoints during the first month. The number of CAR+ cells in blood was determined by qPCR. Kinetics and association of these markers with CRS and NE were analyzed. The treatment-related profile was defined by analytes with at least double an increase over baseline in at least 50% of patients. These analytes were selected and evaluated for association with Gr 3+ CRS or NE. Immune signatures were determined based on p-values applied to peak or cumulative levels of analytes and adjusted for multiplicity (stepdown method). Results: Out of 44 analytes measured, 12 demonstrated an increase by double over baseline in at least 50% of patients. This axi-cel-related biomarker profile includes immune proliferative/modulating cytokines, pro-inflammatory cytokines, markers of myeloid activation, and chemokines. Markers with the highest median-fold increase were IFNγ (44x), IL-10 (31x), IL-6 (26x), IL-15 (20x), and GRZB (17x). These peaked within 7-14 days and generally returned to baseline within 1 month post-treatment. Within this panel of 12 analytes elevated post-axi-cel treatment, markers associated with Gr 3+ CRS (p&lt;0.05) were IL-10, IL-6, IL-2Rα, IL-8, MCP-1, IFNγ, IL-1Rα, and IP-10. Markers associated with Gr 3+ NE (p&lt;0.05) were IL-6, IL-15, IL-8, and MCP-1. Peak levels of CAR T cells in blood, occurring within 14 days post-infusion, were associated with Gr 3+ NE (p=0.02) but not Gr 3+ CRS (p=0.6). A majority of patients with Gr 3+ NE had only Gr 0-2 CRS (16/22) while nearly 50% of patients with Gr 3+ CRS had Gr 0-2 NE (5/11). Conclusions: Biomarker and clinical evaluation suggests mechanistic differences underlying CRS and NE following axi-cel treatment. While Gr 3+ NE was associated with CAR T cell expansion, Gr 3+ CRS was instead associated with a broader array of serum markers, many linked to systemic myeloid activation. Further understanding of these immune signatures may provide insight into managing AEs associated with anti-CD19 CAR T cell therapy. Citation Format: Frederick L. Locke, John Rossi, Xiaodong Xue, Sattva S. Neelapu, Daniel H. Ryan, Armin Ghobadi, Lazaros J. Lekakis, David Miklos, Caron A. Jacobson, Ira Braunschweig, Olalekan Oluwole, Tanya Siddiqi, Yi Lin, John Timmerman, Patrick M. Reagan, Marika Sherman, Janice Nagatani, Xiao Zhang, Lynn Navale, William Y. Go, Jeff Wiezorek, Adrian Bot. Immune signatures of cytokine release syndrome and neurologic events in a multicenter registrational trial (ZUMA-1) in subjects with refractory diffuse large B cell lymphoma treated with axicabtagene ciloleucel (KTE-C19) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr CT020. doi:10.1158/1538-7445.AM2017-CT020

Abstract Introduction: Outcomes for pts with refractory aggressive NHL are poor with current therapies (Crump, ASCO 2016). Results from the interim analysis of (n=62) of ZUMA-1, the 1st multicenter trial of an anti-CD19 chimeric antigen receptor (CAR) T cell, axi-cel, in refractory aggressive NHL, showed an objective response rate (ORR) of 79% (complete response [CR] 52%; Blood 2016;128:LBA-6). Here we present results from the primary analysis of ZUMA-1. Methods: Pts received a target dose of 2 × 106 anti-CD19 CAR T cells/kg after lowdose conditioning with cy/flu. Eligible pts (≥18 y) had diffuse large B cell lymphoma (DLBCL), primary mediastinal B cell lymphoma (PMBCL) or transformed follicular lymphoma (TFL); an ECOG performance status (PS) 0-1; and refractory disease (progressive or stable disease as best response to last prior therapy, or relapsed ≤12 m of autologous stem cell transplant [ASCT]). The primary endpoint for this analysis was ORR in the combined DLBCL, PMBCL, and TFL population. Key secondary endpoints were duration of response (DOR), overall survival (OS), and frequency of adverse events (AEs). The primary analysis was triggered when 92 pts had at least 6 m of follow-up. Results: As of January 27, 2017, 111 pts from 22 institutions were enrolled; 101 pts (91%) received axi-cel. Median age was 58 y (range, 23-76), 67% male, 85% stage IIIIV, 47% IPI 3-4, 77% refractory to ≥2nd line of therapy, and 21% relapsed ≤12 m of ASCT. Axi-cel was successfully manufactured in 110/111 (99%) pts with an average turnaround time from apheresis to the clinical site of 17 d. With an ORR of 82% (n = 92; P&lt;.0001) the study met the primary endpoint. The ORR in the mITT analysis set of 101 pts was 82% (CR 54%, PR 28%), and was consistent across key covariates including disease subtype, refractory status, stage, and IPI score. At a median follow up of 8.7 m, 44% of pts were in response and 39% were in CR. The median DOR was 8.2 m overall and not reached for pts who achieved a CR. Median OS was not reached; 80% of pts remained alive at 6 m. The most common Gr ≥3 treatmentemergent AEs were neutropenia (66%), leukopenia (44%), anemia (43%), febrile neutropenia (31%), and encephalopathy (21%). Gr ≥3 cytokine release syndrome (CRS) and neurologic events (NE) occurred in 13% and 28% of pts, respectively. All CRS and all NE resolved except 1 Gr 1 memory impairment. As previously reported, there were 3 Gr 5 AEs (3%). Peak and cumulative CAR T levels post-axi-cel were associated with durable responses. Conclusions: Axi-cel significantly improved ORR in patients with refractory aggressive NHL. The CR rate was 7-fold higher compared to historical controls (Crump, ASCO 2016) and nearly half the patients have an ongoing response. Axi-cel demonstrated significant clinical benefit with a manageable safety profile in pts lacking curative treatment options.[F.L.L. and S.S.N. contributed equally to this study.] Funding source: Kite Pharma and in part by funding from the Leukemia & Lymphoma Society (LLS) Therapy Acceleration Program treatment options. Citation Format: Frederick L. Locke, Sattva S. Neelapu, Nancy L. Bartlett, Lazaros J. Lekakis, David Miklos, Caron A. Jacobson, Ira Braunschweig, Olalekan Oluwole, Tanya Siddiqi, Yi Lin, John Timmerman, Jonathan W. Friedberg, Adrian Bot, John Rossi, Lynn Navale, Yizhou Jiang, Jeff Aycock, Meg Elias, Jeff Wiezorek, William Y. Go. Primary results from ZUMA-1: a pivotal trial of axicabtagene ciloleucel (axicel; KTE-C19) in patients with refractory aggressive non-Hodgkin lymphoma (NHL) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr CT019. doi:10.1158/1538-7445.AM2017-CT019