Lin, Yi

Abstract Introduction Chimeric antigen receptor T cell (CAR-T) expansion has been consistently identified as a predictor of clinical response. However, there are no clinically available test to measure CAR-T presence after infusion for the FDA approved CAR-T therapy. We hypothesize that the lymphocyte expansion which can be readily measured as absolute lymphocyte count (ALC) in blood count differential could be a clinically accessible surrogate for CAR-T expansion in patients who receive FDA approved CD19 CAR-T to treat aggressive B-cell non-Hodgkin lymphoma (NHL). We examined the ALC levels in the first 2 weeks after CAR-T infusion and correlation with clinical outcomes in NHL patients who received CAR-T at our institution. Methods Records were reviewed for patients who received CAR-T between 6/2016 and 1/2021 at Mayo Clinic, Rochester. CAR+ T cells were identified by flow cytometry using an anti-FMC63 antibody. Receiver operator curve was generated using nominal logistic regression to predict complete response (CR) as best response. Progression-free survival and overall survival were calculated using Kaplan-Meier method and between-group differences were assessed using log-rank test. Continuous variables were compared using wilcoxon text and categorical variables were compared using chi-square test. Results Among the 87 patients who received CAR-T for NHL, majority of the pts received axicabtagene ciloleucel (86, 99%). The highest ALC level (ALC peak) in the first 15 days were identified for all patients and median ALC peak was 0.44 X10 9/L (range, 0 - 2.55x10 9/L). The median time to ALC peak was 10 ±3 days. Increasing ALC peak levels correlated with increased CAR+ T cells in blood measured by flow cytometry (n=16, R=0.63, p=0.0008). Using ROC analysis, an ALC peak level of 0.67 was identified as the cut point for best association with CR (AUC=0.68, p=0.0004). Baseline demographics were similar between the high ALC peak (N=35) and low ALC peak (N=52) groups, as shown in Table 1. There was no difference in the incidence, high grade, or duration of cytokine release syndrome (CRS) and immune effector associated neurotoxicity syndrome (ICANS) between the two groups (Table 2). Patients who received a higher cumulative dose of steroid for management of CRS and ICANS had lower ALC peak. A higher ALC peak was associated with an increased CR rate and durable CR at month 6. Similarly, a higher ALC peak was associated with increased progression-free survival (PFS, 6.4 months vs. 2.7 months, p=0.004) and overall survival (OS, 31 months vs. 12 months, p=0.04), as shown in figure 1. Conclusion Given the typical CAR-T expansion seen in the first 2 weeks post infusion, ALC peak in the first 15 days is a clinically accessible, reliable surrogate for CAR-T expansion and predicts durable CR and longer PFS, OS. This study was supported in part by the Mayo Clinic Center for Individualized Medicine, Bernard E. and Edith B. Waterman, Henry J. Predolin Foundation and other generous benefactors of Mayo Clinic. Figure 1 Figure 1. Disclosures Bennani: Verastem: Other: Advisory Board; Purdue Pharma: Other: Advisory Board; Daichii Sankyo Inc: Other: Advisory Board; Kyowa Kirin: Other: Advisory Board; Vividion: Other: Advisory Board; Kymera: Other: Advisory Board. Paludo: Karyopharm: Research Funding. Wang: Genentech: Research Funding; Eli Lilly: Membership on an entity's Board of Directors or advisory committees; LOXO Oncology: Membership on an entity's Board of Directors or advisory committees, Research Funding; MorphoSys: Research Funding; InnoCare: Research Funding; Incyte: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Research Funding; TG Therapeutics: Membership on an entity's Board of Directors or advisory committees. Ansell: Bristol Myers Squibb, ADC Therapeutics, Seattle Genetics, Regeneron, Affimed, AI Therapeutics, Pfizer, Trillium and Takeda: Research Funding. Lin: Janssen: Consultancy, Research Funding; Legend: Consultancy; Bluebird Bio: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Vineti: Consultancy; Gamida Cell: Consultancy; Kite, a Gilead Company: Consultancy, Research Funding; Novartis: Consultancy; Takeda: Research Funding; Merck: Research Funding; Sorrento: Consultancy; Juno: Consultancy.

Abstract Background: Polatuzumab vedotin (Pola), an antibody drug conjugate targeting CD79b received FDA approval in combination with bendamustine and rituximab (Pola-BR) in June 2019. With CAR-T as destination therapy, the option of Pola-BR appears appealing with its superior efficacy and lack of potential interference with CAR-T due to different target antigens. However, clinical concerns remain regarding prolonged lymphopenia associated with benda and CAR-T manufacturing if used before apheresis. We reviewed the single center experience of all patients with exposure to polatuzumab around CAR-T for R/R aggressive NHL treated at Mayo Clinic Rochester. Methods: A review of patients that received at least one dose of Pola with the intent to proceed to CAR-T between July 1, 2019 and March 31st, 2021 at Mayo Clinic, Rochester were included. Response to therapy was based on 2014 Lugano criteria. Overall survival (OS) was defined as the time from CAR-T infusion to death, and event-free survival (EFS) as the time from CAR-T infusion to disease progression, next treatment, or death. Survival curves were calculated using Kaplan-Meier estimates, and were compared between subgroups using the log-rank test. Cox regression was used for multivariate analysis (MVA). Results: A total of 22 patients were identified during the study period. Of these 18 (82%), made it to CAR-T infusion (17 axi-cel, and 1 -tisa cel). 3 patients died due to progressive disease (PD) before CAR-T and one achieved complete remission (CR). In the pre-CAR-T Pola cohort (n = 22), the median age was 65.5 years (39-73), 50% were males, 96% had advanced stage and IPI ≥ 3. Median prior lines of treatment were 4.5 (2-6), 73% had primary refractory disease and 50% had myc rearrangement. 19 (86%) patients received Pola as bridging therapy and 8 were exposed to Pola before T-cell apheresis. Bendamustine was included in the treatment for 79% (15/19) for bridging therapy and 63% (5/8) with exposure pre-apheresis. For those in the bridging group, the overall response rate (ORR) was 26% (5/19), with one patient achieving CR with Pola-BR. Disease control (defined as those in a partial response [PR] or stable disease [SD]) was seen in 47% (9/19) patients. One of the 8 patients with pre-apheresis exposure to Pola, required an additional attempt at CAR-T manufacturing after the initial failure. At a median follow up of 48 weeks, the EFS and OS in 18 patient cohort with pre-CAR-T Pola exposure were 6.7 weeks (95% CI, 4.3-not reached [NR]) and 15 weeks (95% CI, 9.7-NR), respectively. At the data cut off (7/25/2021), 78% patients had died. As traditional chemo for bridging is a particularly poor prognostic group, we compared Pola-BR bridging group (n = 15), to other traditional chemo bridge group (n = 16) in our CAR-T database. Both groups had comparable baseline characteristics as shown in Table 1 except for higher proportion of patients with B-symptoms in the Pola-BR group at time of CAR-T. There was also no difference in the inflammatory markers (CRP and ferritin) at LD or peak level after CAR-T. Table 2 shows outcomes between the 2 groups with comparable any grade CRS, neurotoxicity, pre and post CAR-T infection rates. Best response ORR to CAR-T was higher in the other chemo group vs. Pola BR (81.2% vs. 33%, p = 0.027). There was a significant difference in the 6-month OS rate (other 81.3% [95%CI, 54.5-96] vs. pola 33.3% [95%CI, 11.8- 61.6], p = 0.007) but no significant difference in the 6-month EFS rate (other 37.5% [95%CI, 15.2-64.6%] vs. pola 13.3% [95%CI, 1.7-40.5%] p = 0.12) between the 2 groups (figure 1). On univariate analysis within the chemo type bridging cohort (Pola-BR + other traditional chemo, n = 31), presence of B-symptoms (HR 4.72, p = 0.002), ECOG PS > 2 at CAR-T (HR 6.75, p = 0.0008), and type of bridge therapy (pola HR 6.57, p = 0.009) were associated with worse OS whereas a response to bridge (PR+SD, HR 0.39, 0.031) was favorable. On MVA, association was maintained for bridge type (pola, p <0.001) and response to bridge (p <0.001). Discussion: Pola based bridge was feasible in this US based cohort without significant issues with CAR-T manufacturing or increased infection rates. However, in this retrospective analysis, use of Pola-BR was associated with inferior outcomes compared to other traditional chemotherapy options. Future studies are required to elucidate whether these difference in outcomes stem from a biological basis versus bias in patient selection. Figure 1 Figure 1. Disclosures Wang: TG Therapeutics: Membership on an entity's Board of Directors or advisory committees; MorphoSys: Research Funding; Incyte: Membership on an entity's Board of Directors or advisory committees, Research Funding; Eli Lilly: Membership on an entity's Board of Directors or advisory committees; LOXO Oncology: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Research Funding; Genentech: Research Funding; InnoCare: Research Funding. Paludo: Karyopharm: Research Funding. Bennani: Kymera: Other: Advisory Board; Vividion: Other: Advisory Board; Kyowa Kirin: Other: Advisory Board; Daichii Sankyo Inc: Other: Advisory Board; Purdue Pharma: Other: Advisory Board; Verastem: Other: Advisory Board. Ansell: Bristol Myers Squibb, ADC Therapeutics, Seattle Genetics, Regeneron, Affimed, AI Therapeutics, Pfizer, Trillium and Takeda: Research Funding. Lin: Bluebird Bio: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Merck: Research Funding; Kite, a Gilead Company: Consultancy, Research Funding; Novartis: Consultancy; Janssen: Consultancy, Research Funding; Juno: Consultancy; Vineti: Consultancy; Takeda: Research Funding; Gamida Cell: Consultancy; Legend: Consultancy; Sorrento: Consultancy.

Abstract Background: Bridging therapy (BT) was not allowed in the ZUMA-1 pivotal trial for axicabtagene ciloleucel (axi-cel) chimeric antigen receptor T-cell therapy (CAR-T) . Since then, several real-world studies have shown the use of bridging therapy to be associated with worse overall survival, duration of response, and complete remission rates. In addition, patients requiring BT during CAR-T manufacturing have a more aggressive and higher tumor burden of disease, also factors associated with poor outcomes. Therefore, factors that can predict outcomes in this high-risk patient cohort are required. We herein examine the impact of response to BT on CAR-T outcomes in large B-cell lymphoma (LBCL). Methods: A retrospective review of patients who received axi-cel for NHL from June 2016 - July 2020 at Mayo Clinic, Rochester, was performed. BT was defined as any lymphoma-directed therapy given between leukapheresis and CAR-T infusion. Patients received BT if there were concerns for symptomatic progression of disease during CAR-T manufacturing, reducing the likelihood of eligibility to receive CAR-T. The decision and choice of BT were at the discretion of the treating physician. Response to all lymphoma-directed therapy was evaluated using the 2014 Lugano criteria. Response to BT included patients with a partial response (PR) or stable disease (SD) on PET-CT before initiating lymphodepletion chemotherapy. Event-free survival (EFS) was defined as the time from axi-cel infusion to progression, next treatment, or death. Overall survival (OS) was defined as the time from axi-cel infusion to death. Survival curves were calculated using Kaplan-Meier estimates and were compared between subgroups using the log-rank test. Cox regression was used for univariate and multivariate analysis (MVA). Results: A total of 73 patients underwent car T therapy during this period. Of these, 67% (49/73) received BT therapy. Table 1 shows baseline characteristics of the total BT cohort (n = 49). The median age at CAR-T infusion was 59 years (IQR 46-64); 57% were males and comprised of 47% (23/49) DLBCL followed by 31% (15/49) high-grade B-cell lymphoma types. Based on the Lugano criteria on PET-CT, 22/49 (45%) patients responded to BT. The baseline characteristics were comparable between the responders and non-responders to BT except for a higher proportion (73%) of patients receiving systemic chemotherapy as BT in the responders (Table 1). At a median follow-up of 24 months, 75% had either progressed, died, or started the next treatment (event), and 59% (29/49) had died. The median EFS was significantly longer in the responders as compared to the non-responders to BT, figure 1 (13.04 months (95%CI, 3.54-not reached [NR]) vs. 2.56 months (95%CI, 1.18-3.02), p = 0.002). The OS also trended in favor of the responders (median OS 18.4 months (95% CI, 13.44-NR) vs. 11.84 months (95% CI, 5.05-NR), p = 0.092). The responder group also had a higher 6-month CR rate of 50% than 11.1% in the non-responder group (p = 0.004). There were no differences in any grade or grade ≥ 3 cytokine release syndrome and neurotoxicity rates in the two groups. On univariate analysis within the bridging group (n = 49), type of bridge (non-chemo) and response to bridge (PR+SD) were associated with a better EFS. In the MVA, only response to BT maintained significance for EFS (HR 0.34, p = 0.025). Conclusions: Having some control of lymphoma after BT was associated with better EFS and 6-month CR rate. Future studies need to prospectively evaluate the type and response to BT as a prognostic factor for improving outcomes in patients receiving CAR-T. Figure 1 Figure 1. Disclosures Wang: InnoCare: Research Funding; Incyte: Membership on an entity's Board of Directors or advisory committees, Research Funding; LOXO Oncology: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Research Funding; Genentech: Research Funding; MorphoSys: Research Funding; Eli Lilly: Membership on an entity's Board of Directors or advisory committees; TG Therapeutics: Membership on an entity's Board of Directors or advisory committees. Paludo: Karyopharm: Research Funding. Bennani: Kymera: Other: Advisory Board; Vividion: Other: Advisory Board; Kyowa Kirin: Other: Advisory Board; Daichii Sankyo Inc: Other: Advisory Board; Purdue Pharma: Other: Advisory Board; Verastem: Other: Advisory Board. Ansell: Bristol Myers Squibb, ADC Therapeutics, Seattle Genetics, Regeneron, Affimed, AI Therapeutics, Pfizer, Trillium and Takeda: Research Funding. Lin: Kite, a Gilead Company: Consultancy, Research Funding; Janssen: Consultancy, Research Funding; Novartis: Consultancy; Celgene: Consultancy, Research Funding; Bluebird Bio: Consultancy, Research Funding; Juno: Consultancy; Legend: Consultancy; Sorrento: Consultancy; Gamida Cell: Consultancy; Vineti: Consultancy; Merck: Research Funding; Takeda: Research Funding.

Abstract Background: Chimeric antigen receptor T cell therapy (CAR-T) is a recent therapeutic advance for the treatment of myeloma. Among the FDA approved and investigational CAR-T, primary refractory disease post CAR-T infusion is uncommon, however most patients eventually relapse. To gain insight to the myeloma cell and immune cell characteristics associated with early relapse (PD) versus durable response (DR), we examined myeloma cells and immune cells in both the bone marrow and blood by single cell RNA-seq. Method: Bone marrow aspirate and blood samples were collected prior to BCMA targeted CAR-T therapy. CD138 + and CD138 neg cells from bone marrow (BM) and peripheral blood mononuclear cells (PBMNC) were collected for 5' based scRNA-seq (10X Genomics). CD138 + cells were clustered by Harmony integration. Top expressing genes in unique clusters for PD and DR were analyzed by Ingenuity Pathway Analyses. To profile CD138 neg BM cells and PBMNC from myeloma patients, the scRNA-seq dataset was mapped to the human PBMC reference using the Seurat v4 reference-guiding approach. Differential gene expression between responders and non-responders was performed using the FindMarkers function for each of the immune cell clusters in the BM and PB. Results: BM and PB samples from 15 patients were analyzed. Among these, 5 patients had relapsed disease more than 1-year post CAR-T infusion (Durable Response, DR), and 10 patients had relapse within 1 year (early relapse, PD). Among these, CD138+ cells were available from 3 DR and 4 PD for analysis. Multimodal expression of BCMA were seen among the CD138+ cells across all samples. Using the mode of the highest expression level as a cut-off, patients with DR had a trend toward having higher fraction of BCMA high CD138+ cells compared to pts with PD. Clustering of all CD138+ cells by Harmony integration identified 12 distinct clusters, among which two clusters were unique to pts in DR, and one was unique to patients in PD. Ingenuity pathway analysis identified the top marker genes in these 3 clusters to be enriched in pathways for IL-15 signaling, BCR signaling, and primary immunodeficiency signaling. (Figure 1A-E.) Differential gene expression for immune cell clusters from CD138 neg BM cells and PBMNC were compared between pts in PD and DR. Interestingly, different patterns were seen in immune cells in PB and BM (Figure 1G). For example, compared to pts in PD, those with DR had decreased signaling in CD16 PB monocytes for interferon signaling and differentiation to macrophages, whereas the CD16 monocytes in the BM in pts in DR had increased expression of mitochondrial genes for anti-oxidant stress, polarization to M1 macrophage and anti-apoptosis. Similarly, pts in DR had CD8 Tcm in the BM with increased expression of genes involved in cell adhesion and anti-apoptosis, and CD4 Tcm in the BM with increased expression of genes in protein metabolism. Conclusion: scRNAseq analysis of myeloma cells suggest different tumor transcriptome profile may be identified in myeloma cells that could relapse early after CAR-T therapy. In addition, host immune profile both in the BM microenvironment and in systemic PB circulation could be associated with durable clinical response. Figure 1 Figure 1. Disclosures Kapoor: Pharmacyclics: Consultancy; Glaxo SmithKline: Research Funding; Amgen: Research Funding; Sanofi: Research Funding; AbbVie: Research Funding; Ichnos Sciences: Research Funding; Sanofi: Consultancy; Regeneron Pharmaceuticals: Research Funding; Takeda: Research Funding; Karyopharm: Research Funding; Karyopharm: Consultancy; Cellectar: Consultancy; BeiGene: Consultancy. Dingli: GSK: Consultancy; Janssen: Consultancy; Sanofi: Consultancy; Novartis: Research Funding; Apellis: Consultancy; Alexion: Consultancy. Kumar: Bluebird Bio: Consultancy; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; KITE: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Tenebio: Research Funding; Novartis: Research Funding; BMS: Consultancy, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche-Genentech: Consultancy, Research Funding; Astra-Zeneca: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Antengene: Consultancy, Honoraria; Carsgen: Research Funding; Oncopeptides: Consultancy; Beigene: Consultancy; Amgen: Consultancy, Research Funding; Merck: Research Funding; Adaptive: Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Research Funding. Lin: Merck: Research Funding; Kite, a Gilead Company: Consultancy, Research Funding; Takeda: Research Funding; Bluebird Bio: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Sorrento: Consultancy; Juno: Consultancy; Legend: Consultancy; Gamida Cell: Consultancy; Vineti: Consultancy; Novartis: Consultancy; Janssen: Consultancy, Research Funding.

Abstract Background: ZUMA-1 is the registrational Phase 1/2 study of axi-cel, an autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy, in pts with refractory LBCL. In ZUMA-1 Cohorts 1+2 (C1+2; N=101), rates of Grade (Gr) ≥3 cytokine release syndrome (CRS) and neurologic events (NEs) were 13% and 28%, respectively, at the 6-mo primary analysis; the objective response rate (ORR) was 82% (54% complete response [CR]; Neelapu et al. NEJM. 2017). ZUMA-1 safety management C6 assessed whether prophylactic and earlier corticosteroids and/or tocilizumab could reduce incidence and severity of CRS and NEs. With a median follow-up of 8.9 mo (N=40) for C6, there were no Gr ≥3 CRS, a low rate of Gr ≥3 NEs (13%), and high response rates (Oluwole et al. BJH. 2021). Here, we present a 1-yr updated analysis of C6 supported by propensity score matching (PSM) analysis to compare outcomes for pts in C6 vs C1+2. Methods: Eligible pts could receive optional bridging therapy after leukapheresis. Pts received conditioning chemotherapy for 3 d prior to a single axi-cel infusion. Pts received once-daily oral dexamethasone 10 mg on Days 0 (before axi-cel), 1, and 2; corticosteroids and/or tocilizumab for adverse event (AE) management were given earlier vs C1+2. The primary endpoints were incidence and severity of CRS and NEs. Other endpoints included efficacy outcomes and biomarker analyses. To ensure comparability for pts in C6 and C1+2, an exploratory PSM analysis was performed after balancing for key baseline disease characteristics (tumor burden, IPI score, no. of prior lines of chemotherapy, disease stage, and LDH level). Results: As of December 16, 2020, the median follow-up time was 14.9 mo. Gr ≥3 AEs were reported in all 40 treated pts, and the most common were neutropenia (45%), neutrophil count decreased (33%), and white blood cell count decreased (23%). No Gr ≥3 CRS occurred. Gr ≥3 NEs were reported in 15% of pts. Median time to CRS and NE onset was 5 and 6 d, respectively, after axi-cel infusion. Infections of any grade occurred in 50% of pts (20% Gr ≥3). Since the 6-mo analysis, no new cases of CRS were observed. Four new axi-cel-related NEs occurred in 2 pts (pt 1: Gr 2 mental status changes and seizure-like phenomena both on Day 441; pt 2: Gr 1 dementia [occurred on Day 93 but was reported late] and Gr 5 toxic encephalopathy on Day 369 [resultant from a Gr 4 event that started on Day 351]). Two new infections of Gr 2 pneumonia and Gr 1 bronchitis were observed; the latter was axi-cel-related. One death due to progressive disease occurred. The investigator-assessed ORR was 95% (80% CR). Median DOR, PFS, and OS were not reached. Kaplan-Meier estimates of the 12-mo DOR, PFS, and OS rates were 60%, 63%, and 82%, respectively. At data cutoff, 53% of pts were in ongoing response. Median peak CAR T-cell levels were comparably high in pts with ongoing response and relapse (64 cells/µL [n=21] and 66 cells/µL [n=15], respectively) at 12 mo and considerably lower in nonresponders (18 cells/µL [n=2]). In all, 32 matched pts each in C6 and C1+2 were identified during PSM analysis; 8 pts from C6 were not included due to nonavailability of matched pts in C1+2. No Gr ≥3 CRS was observed in C6 vs 13% of pts in C1+2. Incidence of Gr ≥3 NEs was comparable in C6 and C1+2 (19% and 22%, respectively), with median time to onset of 12 d in C6 vs 7 d in C1+2. The ORR was 94% in both C6 and matched C1+2 (75% and 78% CR rates, respectively); 47% and 59% of pts were in ongoing response at 12 mo. The Kaplan-Meier estimate of the 12-mo PFS rate was 61% in both C6 and matched C1+2. Median peak CAR T-cell levels were 65 and 43 cells/µL, respectively, in C6 and C1+2. Serum levels of inflammatory biomarkers associated with CAR T-cell treatment-related AEs (IFN-γ, IL-2, GM-CSF, and ferritin) were lower in C6 vs C1+2. Median cumulative corticosteroid dose including prophylaxis was 1252 mg in C6 (n=32) and 7418 mg in C1+2 (n=6). Conclusion: With ≥1-y follow-up, prophylactic and earlier corticosteroid and/or tocilizumab intervention continued to demonstrate a manageable safety profile, absence of new safety signals, and high, durable response rates, which was corroborated by PSM analysis. Although fewer pts in C1+2 received corticosteroids after matching, the median cumulative corticosteroid dose was 4-fold lower in C6 vs C1+2. These findings suggest that the C6 AE management strategy can improve long-term safety of axi-cel in R/R LBCL without compromising durability of responses. Disclosures Oluwole: Pfizer: Consultancy; Curio Science: Consultancy; Janssen: Consultancy; Kite, a Gilead Company: Consultancy, Research Funding. Forcade: Jazz: Other: Travel Support, Speakers Bureau; MSD: Other: Travel Support; Gilead: Other: Travel Support, Speakers Bureau; Novartis: Consultancy, Other: Travel Support, Speakers Bureau. Muñoz: Targeted Oncology: Honoraria; Seagen: Consultancy, Honoraria, Speakers Bureau; Physicians' Education Resource: Honoraria; Kyowa Kirin: Consultancy, Honoraria, Speakers Bureau; OncView: Honoraria; Pharmacyclics: Consultancy, Speakers Bureau; Bayer: Consultancy, Speakers Bureau; Kite, a Gilead Company: Consultancy, Speakers Bureau; Pfizer: Consultancy; Janssen: Consultancy, Speakers Bureau; Juno/Celgene: Consultancy; Bristol Myers Squibb: Consultancy; Alexion: Consultancy; BeiGene: Consultancy, Speakers Bureau; Fosunkite: Consultancy; Innovent: Consultancy; Debiopharma: Consultancy; Karyopharm: Consultancy; Genmab: Consultancy; ADC Therapeutics: Consultancy; Epizyme: Consultancy; Servier: Consultancy; Acrotech: Speakers Bureau; Verastem: Speakers Bureau; AstraZeneca: Speakers Bureau; Celgene/Bristol Myers Squibb: Speakers Bureau; Genentech: Speakers Bureau; Aurobindo: Speakers Bureau. de Guibert: Gilead: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria; Janssen: Consultancy, Honoraria. Vose: Kite, a Gilead Company: Honoraria, Research Funding. Bartlett: Roche/Genentech: Consultancy; Seagen: Consultancy, Research Funding; Autolus: Research Funding; Bristol Myers Squibb: Research Funding; Celgene: Research Funding; Forty Seven: Research Funding; Genentech: Research Funding; Janssen: Research Funding; Kite, a Gilead Company: Research Funding; Merck: Research Funding; Millennium: Research Funding; Pharmacyclics: Research Funding; ADC Therapeutics: Consultancy, Research Funding. Lin: Juno: Consultancy; Takeda: Research Funding; Gamida Cell: Consultancy; Vineti: Consultancy; Merck: Research Funding; Sorrento: Consultancy; Legend: Consultancy; Celgene: Consultancy, Research Funding; Novartis: Consultancy; Janssen: Consultancy, Research Funding; Bluebird Bio: Consultancy, Research Funding; Kite, a Gilead Company: Consultancy, Research Funding. Deol: Kite, a Gilead Company: Consultancy. McSweeney: Kite, a Gilead Company: Consultancy, Honoraria, Research Funding, Speakers Bureau; Novartis: Research Funding; Autolus: Research Funding; Allovir: Research Funding. Goy: Acerta: Consultancy, Research Funding; AstraZeneca: Membership on an entity's Board of Directors or advisory committees; Xcenda: Consultancy, Honoraria; Vincerx: Honoraria, Membership on an entity's Board of Directors or advisory committees; Elsevier's Practice Update Oncology, Intellisphere, LLC(Targeted Oncology): Consultancy; MorphoSys: Honoraria, Other; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Consultancy, Honoraria; Bristol Meyers Squibb: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; AbbVie/Pharmacyclics: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; LLC(Targeted Oncology): Consultancy; Kite Pharma: Membership on an entity's Board of Directors or advisory committees; OncLive Peer Exchange: Honoraria; Rosewell Park: Consultancy; Genomic Testing Cooperative: Current holder of stock options in a privately-held company, Membership on an entity's Board of Directors or advisory committees, Other: Leadership role; COTA (Cancer Outcome Tracking Analysis): Current holder of stock options in a privately-held company, Membership on an entity's Board of Directors or advisory committees, Other: Leadership role; Celgene: Consultancy, Honoraria, Research Funding; Xcenda: Consultancy; Gilead: Membership on an entity's Board of Directors or advisory committees; Michael J Hennessey Associates INC: Consultancy; Bristol Meyers Squibb: Membership on an entity's Board of Directors or advisory committees; Medscape: Consultancy; AbbVie/Pharmacyclics: Membership on an entity's Board of Directors or advisory committees; Hoffman la Roche: Consultancy; Infinity/Verastem: Research Funding; Genentech/Hoffman la Roche: Research Funding; Physicians' Education Resource: Consultancy, Other: Meeting/travel support; Janssen: Membership on an entity's Board of Directors or advisory committees; Vincerx pharma: Membership on an entity's Board of Directors or advisory committees; Incyte: Honoraria; AstraZeneca: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Kite, a Gilead Company: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Elsevier PracticeUpdate: Oncology: Consultancy, Honoraria; Janssen: Research Funding; Karyopharm: Research Funding; Phamacyclics: Research Funding; Constellation: Research Funding; Hackensack Meridian Health, Regional Cancer Care Associates/OMI: Current Employment. Kersten: Miltenyi Biotec: Consultancy, Honoraria, Other: Travel support; Roche: Consultancy, Honoraria, Other: Travel support, Research Funding; BMS/Celgene: Consultancy, Honoraria; Takeda: Research Funding; Celgene: Research Funding; Kite, a Gilead Company: Consultancy, Honoraria, Other: Travel support, Research Funding; Novartis: Consultancy, Honoraria, Other: Travel support. Jacobson: Nkarta: Consultancy, Honoraria; Novartis Pharmaceuticals Corporation: Consultancy, Honoraria, Other: Travel support; Humanigen: Consultancy, Honoraria, Other: Travel support; Lonza: Consultancy, Honoraria, Other: Travel support; AbbVie: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria, Other: Travel support, Research Funding; Precision Biosciences: Consultancy, Honoraria, Other: Travel support; Kite, a Gilead Company: Consultancy, Honoraria, Other: Travel support; Celgene: Consultancy, Honoraria, Other: Travel support; Axis: Speakers Bureau; Clinical Care Options: Speakers Bureau. Farooq: Kite, a Gilead Company: Honoraria. Minnema: Cilag: Consultancy; BMS: Consultancy; Janssen: Consultancy; Celgene: Other: Travel expenses; Kite/Gilead: Consultancy; Alnylam: Consultancy. Thieblemont: Bristol Myers Squibb/Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses ; Kyte: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses ; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses ; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses , Research Funding; Gilead Sciences: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses ; Incyte: Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses ; Cellectis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses ; Hospira: Research Funding; Bayer: Honoraria; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses . Timmerman: Spectrum Pharmaceuticals: Research Funding; Bristol Myers Squibb: Research Funding; Kite, a Gilead Company: Consultancy, Research Funding; Bluebird Bio: Current equity holder in publicly-traded company; TG Therapeutics: Current equity holder in publicly-traded company; Marker Therapeutics: Current equity holder in publicly-traded company; Corvus: Current equity holder in publicly-traded company; Genmab: Current equity holder in publicly-traded company; Merck: Research Funding. Stiff: Macrogenics: Research Funding; Amgen: Research Funding; Kite, a Gilead Company: Research Funding; Seagen: Research Funding; Gamida Cell: Research Funding; Janssen: Research Funding; CRISPR Therapeutics: Consultancy, Honoraria; Karyopharm: Consultancy, Honoraria; Cellectar: Research Funding; Bristol Myers Squibb: Research Funding; Incyte: Research Funding; BioLineRX: Research Funding; Cellectar: Research Funding; MorphoSys: Consultancy, Honoraria; Actinium: Research Funding. Avivi: Novartis: Speakers Bureau; Kite, a Gilead Company: Speakers Bureau. Tzachanis: Fate Therapeutics: Research Funding; Incyte: Research Funding; Genentech: Research Funding; Bristol Myers Squibb: Research Funding; Magenta: Consultancy; Kyowa Kirin: Consultancy; Kite, a Gilead Company: Consultancy, Research Funding, Speakers Bureau; EUSA: Consultancy; Takeda: Consultancy, Speakers Bureau; Partner: Consultancy. Kim: Kite, a Gilead Company: Current Employment; Gilead Sciences: Current equity holder in publicly-traded company. Zheng: Kite, a Gilead Company: Current Employment; Gilead Sciences: Current equity holder in publicly-traded company. Shen: Gilead Sciences: Current equity holder in publicly-traded company; Atara: Current Employment, Current equity holder in publicly-traded company, Other: Leadership role, Patents & Royalties; Kite, a Gilead Company: Current Employment, Other: Leadership role, Patents & Royalties. Vardhanabhuti: Kite, a Gilead Company: Current Employment, Other: Travel support, Research Funding; Gilead Sciences: Current equity holder in publicly-traded company. Van Meerten: Kite, a Gilead Company: Honoraria; Janssen: Consultancy.

Abstract Background Patients (pts) with aggressive B-cell non-Hodgkin lymphoma (NHL) progressing after anti-CD19 chimeric antigen receptor T (CART) cell therapy have poor prognosis and may benefit from new therapy options through clinical trials. However, in a single center report, only 12% of such pts were treated in trials (Chow et al. Am J Hematol, 2019). Identifying the reasons for this low enrollment is needed to design future studies for this population. Here, we evaluated the eligibility criteria for recent landmark trials for relapsed/refractory aggressive B-cell NHL to learn what eligibility barriers are present. Methods Pts with aggressive B-cell NHL who received FDA-approved CART cell therapy at Mayo Clinic (Rochester, Arizona, Florida) since 2018 and progressed after CART cell therapy were identified. The potential eligibility for the following key trials was evaluated: a) polatuzumab + bendamustine + rituximab, b) tafasitamab + lenalidomide, c) selinexor and d) loncastuximab. The eligibility for each trial was retrospectively assessed at the time of disease progression after CART cell therapy based on hemoglobin (Hb), absolute neutrophils count (ANC), platelet count (Plt), renal and liver function tests, ECOG performance status (PS), and central nervous system (CNS) involvement. Results Seventy-five pts had disease progression to axicabtagene ciloleucel (N=73, 97%) or tisagenlecleucel (N=2, 3%) and are included in this analysis. Median time to progression after CART was 2.1 months (IQR: 1.0 - 3.1). Thirteen (17%) pts were treated in clinical trials after progression following CART cell therapy, while 46 (61%) were treated off trials, and 16 (22%) pts never received any treatment after progression. At a median follow-up of 13.6 months (IQR: 9.1 - 26.7) from CART progression, the median overall survival (mOS) from CART progression was 5.8 months (95% CI 3.5 - 10.1) and 53 (71%) pts died. Thirty-eight pts (51%) did not meet eligibility criteria for any of the 4 recent landmark trials. Hematologic impairment was the most common barrier to inclusion of these patients in clinical trials: Hb < 9 g/dL n=23 (31%) or Hb < 10 g/dL n=36 (48%), ANC < 1.0 x 10 9/L n=19 (25%) or ANC < 1.5 x 10 9/L n=32 (43%), and Plt < 75 x 10 9/L n=30 (40%) or Plt < 90 x 10 9/L n=34 (45%). Renal (n=11, 15%) or liver dysfunction (n=5, 7%), CNS involvement (n=8, 11%) and ECOG PS > 2 (n=3, 4%) were less common reasons leading to exclusion from trials. Post CART trial ineligible pts had significantly shorter time to progression (median 1.7 months, IQR: 1.0 - 2.6 vs. 3.0 months IQR: 1.9 - 3.4, p < 0.01) and inferior overall response to CART (45% vs 67%, p = 0.06) compared to pts who met trial eligibility post CART. Baseline Hb (median Hb 9.5 g/dL, IQR: 8.5 - 10.5 vs. 10.9 g/dL, IQR: 9.7 - 12.2, p < 0.01) and Plt (median Plt 106 x 10 9/L IQR: 54 - 165 vs. 201 x 10 9/L IQR: 141 - 243, p < 0.01) were also significantly lower in pts ineligible for trials post CART. There were no significant differences between pts eligible or ineligible for trials with regards to age (median 59 vs. 60 years), number of prior therapies (median 3 vs. 3), prior autologous stem cell transplant (41% vs. 37%), bridging therapy (65% vs. 63%), baseline ANC (median 4,1 vs. 3,0 x10 9/L), or high-grade (grade ≥ 2) cytokine release syndrome (19% vs. 21%) or neurotoxicity (32%, vs. 42%), respectively. Survival after CART progression was significantly shorter (mOS 2.5 months, 95% CI: 1.6 - 5.1) for the 38 pts ineligible for trials compared to pts eligible for trials (mOS 10.6 months, 95% CI: 8.9 - NA), (p < 0.01). In the 59 pts who received therapy post CART progression, the mOS of pts treated on (n = 13) or off (n = 46) trials was 13.8 months (95% CI: 9.2 - NA) vs. 6.6 months (4.9 - 10.7), respectively (p = 0.047). Conclusion Approximately half of the pts (51%) with aggressive B-cell NHL progressing after CART cell therapy would have be excluded from landmark clinical trials. The current hematologic exclusion criteria are a major barrier to enrollment in clinical trials, which would exclude many pts who have disease progression within 3 months of CART cell therapy (ie, primary refractory disease), in whom cytopenia as a toxicity from therapy is prevalent. Given the known delayed hematologic recovery after CART cell therapy and the unmet need of pts progressing to CART cell therapy, the hematologic exclusion criteria should be adjusted to increase trial participation of this population, especially of those with primary refractory disease. Figure 1 Figure 1. Disclosures Munoz: Gilead/Kite Pharma, Kyowa, Bayer, Pharmacyclics/Janssen, Seattle Genetics, Acrotech/Aurobindo, Beigene, Verastem, AstraZeneca, Celgene/BMS, Genentech/Roche.: Speakers Bureau; Janssen: Research Funding; Pharmacyclics/Abbvie, Bayer, Gilead/Kite Pharma, Pfizer, Janssen, Juno/Celgene, BMS, Kyowa, Alexion, Beigene, Fosunkite, Innovent, Seattle Genetics, Debiopharm, Karyopharm, Genmab, ADC Therapeutics, Epizyme, Beigene, Servier: Consultancy; Seattle Genetics: Research Funding; Millennium: Research Funding; Pharmacyclics: Research Funding; Genentech: Research Funding; Incyte: Research Funding; Portola: Research Funding; Merck: Research Funding; Celgene: Research Funding; Gilead/Kite Pharma: Research Funding; Bayer: Research Funding; Seattle Genetics: Honoraria; Physicians' Education Resource: Honoraria; Targeted Oncology: Honoraria; OncView: Honoraria; Kyowa: Honoraria. Murthy: CRISPR Therapeutics: Research Funding. Maurer: Morphosys: Membership on an entity's Board of Directors or advisory committees, Research Funding; Nanostring: Research Funding; Kite Pharma: Membership on an entity's Board of Directors or advisory committees; Celgene: Research Funding; Genentech: Research Funding; Pfizer: Consultancy, Membership on an entity's Board of Directors or advisory committees. Bennani: Purdue Pharma: Other: Advisory Board; Daichii Sankyo Inc: Other: Advisory Board; Kyowa Kirin: Other: Advisory Board; Vividion: Other: Advisory Board; Kymera: Other: Advisory Board; Verastem: Other: Advisory Board. Paludo: Karyopharm: Research Funding. Wang: Genentech: Research Funding; Incyte: Membership on an entity's Board of Directors or advisory committees, Research Funding; MorphoSys: Research Funding; TG Therapeutics: Membership on an entity's Board of Directors or advisory committees; Eli Lilly: Membership on an entity's Board of Directors or advisory committees; LOXO Oncology: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Research Funding; InnoCare: Research Funding. Ansell: Bristol Myers Squibb, ADC Therapeutics, Seattle Genetics, Regeneron, Affimed, AI Therapeutics, Pfizer, Trillium and Takeda: Research Funding. Witzig: Karyopharm Therapeutics, Celgene/BMS, Incyte, Epizyme: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene/BMS, Acerta Pharma, Kura Oncology, Acrotech Biopharma, Karyopharm Therapeutics: Research Funding. Nowakowski: Celgene, NanoString Technologies, MorphoSys: Research Funding; Celgene, MorphoSys, Genentech, Selvita, Debiopharm Group, Kite/Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees. Lin: Vineti: Consultancy; Takeda: Research Funding; Sorrento: Consultancy; Novartis: Consultancy; Juno: Consultancy; Legend: Consultancy; Janssen: Consultancy, Research Funding; Bluebird Bio: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Merck: Research Funding; Gamida Cell: Consultancy; Kite, a Gilead Company: Consultancy, Research Funding.

Abstract Purpose: Axicabtagene ciloleucel (axi-cel) is an anti-CD19 chimeric antigen receptor T-cell (CAR-T) therapy utilized for patients with non-Hodgkin lymphoma (NHL) refractory to at least 2 lines of therapy. F-18 fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) is used to evaluate disease extent prior to CAR-T infusion at two time points: pre-leukapheresis (pre-leuk) approximately 6 weeks prior to CAR-T infusion, and pre-lymphodepletion chemotherapy (pre-LD) approximately 1 week prior to CAR-T infusion. We hypothesized that PET/CT characteristics beyond Lugano criteria, such as metabolic tumor volume (MTV), total lesion glycolysis (TLG), SUV maximum (SUVMax), and changes in these parameters from pre-leuk to pre-LD, may predict for progressive disease (PD), death, and treatment toxicity after CAR-T infusion. Methods: Patients with NHL who received axi-cel on a prospective registry at Mayo Clinic Rochester were included. Lesions on pre-leuk and pre-LD PET/CT scans were segmented with a fixed absolute SUVMax threshold of 2.5 using a semi-automated workflow (LesionID, MIM Software Inc.) with manual modification to exclude physiologic uptake as needed. MTV, TLG, SUVMax, number of lesions, and other lesion characteristics were assessed for each PET/CT, and changes from pre-leuk to pre-LD were calculated. Lesions were categorized as either nodal, spleen, bone, parenchymal (i.e. liver, lung), or soft tissue (i.e. subcutaneous, muscle), and MTV was calculated for each category. Univariate Cox modeling was used to associate relative and directional change in metabolic and volumetric PET/CT characteristics with PD and death, after adjusting for bridging therapy. LASSO method was used for multivariable model selection. Pre-LD PET/CT characteristics were also assessed for association with presence and duration of cytokine release syndrome (CRS), grade 3+ immune effector cell-associated neurotoxicity syndrome (ICANS), tocilizumab (toci) use, and corticosteroid use. Results: From 2018-2020, axi-cel was delivered to 69 patients. Histology included diffuse large B-cell lymphoma (57%), transformed follicular lymphoma (23%), or high-grade lymphoma (19%). Pre-leuk and pre-LD PET/CT scans were performed a median of 46 days and 7 days prior to CAR-T infusion, respectively. Forty patients (58%) received bridging therapy between scans, including 9 (13%) receiving radiotherapy. At a median follow-up of 13 months, 39 (57%) had died and 46 (67%) had PD. Sixty patients (87%) developed CRS following CAR-T infusion for a median duration of 5 days. Presence of pre-LD parenchymal disease was associated with longer duration CRS (p=0.032). Thirty-seven patients (54%) developed ICANS for a median duration of 4.5 days, including 12 (32%) with grade 3+ ICANS. Greater pre-LD total MTV was associated with higher risk of grade 3+ ICANS (p=0.042). Greater pre-LD SUVMax was associated with longer duration ICANS (p=0.032). Nineteen (28%) patients required toci. Greater pre-LD total MTV, SUVMax, TLG, and volume of the largest lesion were associated with increased use of toci (p<0.05 for all). Greater pre-LD total MTV and TLG of the largest lesion were associated with increased use of corticosteroid (p<0.05 for each). While no individual pre-leuk or pre-LD PET/CT characteristics were associated with risk of PD or death, increases from pre-leuk to pre-LD in total MTV, total TLG, parenchymal MTV, and nodal MTV were associated with increased risk of PD (Figure 1). Similarly, increases from pre-leuk to pre-LD in parenchymal MTV, nodal MTV, TLG of the largest lesion, and total number of lesions were associated with increased risk of death (p<0.05 for all). LASSO analysis identified increasing extranodal MTV (≥25% increase) and increasing TLG of the largest lesion (≥10% increase) as strong predictors of death (AUC 0.74, Table 1). Kaplan-Meier plots were generated for overall and progression-free survival using these risk factors (Figure 2). Additional patients and follow-up will be presented. Conclusions: Patients with greater pre-LD MTV had higher risk of grade 3+ ICANS and use of toci or corticosteroids. Increasing metabolic disease burden during CAR-T manufacturing is associated with increased risk of PD and death. A two variable risk score using increasing extranodal disease and increasing TLG of the largest lesion may stratify prognosis prior to CAR-T and inform treatment paradigms. Figure 1 Figure 1. Disclosures Bennani: Verastem: Other: Advisory Board; Purdue Pharma: Other: Advisory Board; Daichii Sankyo Inc: Other: Advisory Board; Kyowa Kirin: Other: Advisory Board; Vividion: Other: Advisory Board; Kymera: Other: Advisory Board. Paludo: Karyopharm: Research Funding. Wang: Genentech: Research Funding; LOXO Oncology: Membership on an entity's Board of Directors or advisory committees, Research Funding; Eli Lilly: Membership on an entity's Board of Directors or advisory committees; Incyte: Membership on an entity's Board of Directors or advisory committees, Research Funding; InnoCare: Research Funding; Novartis: Research Funding; MorphoSys: Research Funding; TG Therapeutics: Membership on an entity's Board of Directors or advisory committees. Ansell: Bristol Myers Squibb, ADC Therapeutics, Seattle Genetics, Regeneron, Affimed, AI Therapeutics, Pfizer, Trillium and Takeda: Research Funding. Lin: Gamida Cell: Consultancy; Janssen: Consultancy, Research Funding; Legend: Consultancy; Novartis: Consultancy; Celgene: Consultancy, Research Funding; Sorrento: Consultancy; Bluebird Bio: Consultancy, Research Funding; Takeda: Research Funding; Kite, a Gilead Company: Consultancy, Research Funding; Merck: Research Funding; Vineti: Consultancy; Juno: Consultancy.

Abstract Introduction: Axicabtagene ciloleucel (axi-cel) is an autologous anti-CD19 Chimeric Antigen Receptor (CAR) T-cell therapy that induces durable responses in patients with relapsed or refractory large B-cell lymphoma. At a median of 27.1 months follow-up on the ZUMA-1 trial, median overall survival (OS) was 25.8 months with 39% progression free survival (PFS) at 2 years post-infusion (Locke, Lancet Onc 2019). We previously reported outcomes of axi-cel patients treated with standard of care therapy at a median follow up of 12.9 months, including 42% who did not meet eligibility criteria for ZUMA-1 based on co-morbidities (Nastoupil, JCO 2020). Here we report results from this cohort at a median follow up of 32.4 months, as well as late outcomes of interest including cytopenias, infections and secondary malignancies. Methods and Results: The US Lymphoma CAR-T Consortium comprised of 17 US academic centers who contributed data independent of the manufacturer. Two hundred and ninety-eight patients underwent leukapheresis with intent to manufacture standard of care axi-cel as of September 30, 2018. In infused patients (n=275), OS and PFS were calculated from date of infusion. After median follow-up of 32.4 months (95% CI 31.1 - 34.3), median OS was not reached (95% CI 25.6 - not evaluable) (Figure 1A) with 1-, 2- and 3-year OS of 68.5% (95% CI 62.6-73.7), 56.4% (95% CI 50.1-62.2) and 52.2% (95% CI 45.7-58.2%), respectively. Median PFS was 9 months (95% CI 5.9-19.6) (Figure 1B); 1-, 2- and 3-year PFS was 47.4% (95% CI 41.4-53.2), 41.6% (95% CI 35.6-47.5) and 37.3% (95% CI 31.3-43.2), respectively. Twenty-seven PFS events occurred at or after 1 year post infusion;19 events were progressive lymphoma, with the latest relapse observed 28 months after axi-cel infusion. Eight patients died while in remission from their lymphoma: 4 from secondary malignancy, 3 from infection, and 1 from unknown causes. Results of multivariable modeling were similar to our prior analysis: factors associated with both a shorter PFS and shorter OS included male sex, elevated pre-lymphodepletion LDH, and poor ECOG status. Complete blood count and B- and T-cell recovery data were collected at 1 and 2-years post-infusion, excluding patients who had relapsed or been treated for secondary malignancy at time of collection (Table 1). Rates of neutropenia (absolute neutrophil count ≤1000) at 1- and 2- years were 9.2% (10/109) and 11.2% (9/80) and rates of CD4 count ≤200/ul were 62% (23/37) and 27% (7/26). Recovery of B cells was seen in 54% (15/28) and 57% (13/23) at 1-and 2-years post infusion. Infections were reported in 31.2% (34/109) patients between 6- and 12-months post infusion, and 17% (18/109) were severe, requiring either hospitalization and/or IV antibiotics. Twenty-one patients (24%, 21/89) had an infection between 1- and 2- years, 11% of which were severe. Twenty percent (10/49) of patients between 2- and 3-years had an infection and 4 (8%) were severe. Neutropenia, low CD4 counts, and IgG levels were not associated with infection, though patients with infection between 6-12 months were more likely to have received IVIG (p<0.001). No patient in this cohort died of COVID-19. Twenty-two of 275 (8%) patients were diagnosed with subsequent malignancy after axi-cel treatment: 14/275 (5%) patients were diagnosed with myeloid malignancies (MDS (n=12), AML (n=1), CMML (n=1)); other malignancies included squamous cell carcinoma of skin (n=3); sarcoma (n=1); endometrial (n=1); lung (n=1); mesothelioma (n=1) and AITL (n=1). Patients with myeloid malignancy had a median age of 62 at axi-cel apheresis (IQR 56-67), 64% were male and median lines of prior therapy was 4 (IQR 3-6), including 36% with a prior autologous stem cell transplant. Eleven patients were in remission from lymphoma at myeloid malignancy diagnosis, while 3 were diagnosed after progression and interval therapy. Conclusion: This multi-center retrospective study showed similar long-term results to the ZUMA-1 trial, despite including patients who did not meet ZUMA-1 eligibility criteria based on comorbidities. Sixteen percent of PFS events were seen after 1 year, largely due to disease progression. Late infection was common but was not explained by persistent neutropenia or low CD4 counts. Subsequent malignancy, including MDS, occurred in 8% of patients and require further study to better identify patients at risk. J.Y.S and M.D.J contributed equally; S.D and M.L contributed equally. Figure 1 Figure 1. Disclosures Jain: BMS, Kite/Gilead, Novartis, Precision Biosciences, Takeda: Consultancy. Nastoupil: Pfizer: Honoraria, Research Funding; MorphoSys: Honoraria; Takeda: Honoraria, Other: DSMC, Research Funding; ADC Therapeutics: Honoraria; IGM Biosciences: Research Funding; Genentech: Honoraria, Research Funding; Epizyme: Honoraria, Research Funding; Caribou Biosciences: Research Funding; Gilead/Kite: Honoraria, Research Funding; TG Therapeutics: Honoraria, Research Funding; Denovo Pharma: Other: DSMC; Bayer: Honoraria; Janssen: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Bristol Myers Squibb/Celgene: Honoraria, Research Funding. Ghobadi: Atara: Consultancy; Amgen: Consultancy, Research Funding; Wugen: Consultancy; Celgene: Consultancy; Kite, a Gilead Company: Consultancy, Honoraria, Research Funding. Lin: Gamida Cell: Consultancy; Juno: Consultancy; Merck: Research Funding; Bluebird Bio: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Novartis: Consultancy; Janssen: Consultancy, Research Funding; Sorrento: Consultancy; Legend: Consultancy; Takeda: Research Funding; Vineti: Consultancy; Kite, a Gilead Company: Consultancy, Research Funding. Reagan: Seagen: Research Funding; Kite, a Gilead Company: Consultancy; Genentech: Research Funding; Curis: Consultancy. Oluwole: Curio Science: Consultancy; Janssen: Consultancy; Pfizer: Consultancy; Kite, a Gilead Company: Consultancy, Research Funding. McGuirk: EcoR1 Capital: Consultancy; Gamida Cell: Research Funding; Bellicum Pharmaceuticals: Research Funding; Novartis: Research Funding; Kite/ Gilead: Consultancy, Honoraria, Other: travel accommodations, expense, Kite a Gilead company, Research Funding, Speakers Bureau; Novartis: Research Funding; Juno Therapeutics: Consultancy, Honoraria, Research Funding; Astelllas Pharma: Research Funding; Pluristem Therapeutics: Research Funding; Fresenius Biotech: Research Funding; Allovir: Consultancy, Honoraria, Research Funding; Magenta Therapeutics: Consultancy, Honoraria, Research Funding. Deol: Kite, a Gilead Company: Consultancy. Sehgal: Juno/Celgene: Research Funding; Kite/Gilead: Research Funding. Goy: AstraZeneca: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; LLC(Targeted Oncology): Consultancy; Xcenda: Consultancy, Honoraria; Xcenda: Consultancy; Acerta: Consultancy, Research Funding; AbbVie/Pharmacyclics: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Vincerx: Honoraria, Membership on an entity's Board of Directors or advisory committees; Elsevier's Practice Update Oncology, Intellisphere, LLC(Targeted Oncology): Consultancy; Hoffman la Roche: Consultancy; Gilead: Membership on an entity's Board of Directors or advisory committees; AbbVie/Pharmacyclics: Membership on an entity's Board of Directors or advisory committees; Janssen: Research Funding; AstraZeneca: Membership on an entity's Board of Directors or advisory committees; Phamacyclics: Research Funding; Bristol Meyers Squibb: Membership on an entity's Board of Directors or advisory committees; Kite Pharma: Membership on an entity's Board of Directors or advisory committees; Michael J Hennessey Associates INC: Consultancy; Genentech/Hoffman la Roche: Research Funding; MorphoSys: Honoraria, Other; Karyopharm: Research Funding; Vincerx pharma: Membership on an entity's Board of Directors or advisory committees; Physicians' Education Resource: Consultancy, Other: Meeting/travel support; Incyte: Honoraria; Medscape: Consultancy; Novartis: Consultancy, Honoraria; Genomic Testing Cooperative: Current holder of stock options in a privately-held company, Membership on an entity's Board of Directors or advisory committees, Other: Leadership role; Infinity/Verastem: Research Funding; Rosewell Park: Consultancy; Bristol Meyers Squibb: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Kite, a Gilead Company: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; OncLive Peer Exchange: Honoraria; Elsevier PracticeUpdate: Oncology: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Research Funding; Constellation: Research Funding; COTA (Cancer Outcome Tracking Analysis): Current holder of stock options in a privately-held company, Membership on an entity's Board of Directors or advisory committees, Other: Leadership role; Hackensack Meridian Health, Regional Cancer Care Associates/OMI: Current Employment. Hill: Pfizer: Consultancy, Honoraria; Beigene: Consultancy, Honoraria, Research Funding; Gentenech: Consultancy, Honoraria, Research Funding; Kite, a Gilead Company: Consultancy, Honoraria, Other: Travel Support, Research Funding; Karyopharm: Consultancy, Honoraria, Research Funding; AstraZenica: Consultancy, Honoraria; Epizyme: Consultancy, Honoraria; Incyte/Morphysis: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria, Research Funding; Celgene (BMS): Consultancy, Honoraria, Research Funding; AbbVie: Consultancy, Honoraria, Research Funding. Andreadis: CRISPR Therapeutics: Research Funding; GenMAB: Research Funding; Novartis: Research Funding; Roche: Current equity holder in publicly-traded company, Ended employment in the past 24 months; Epizyme: Honoraria; Incyte: Honoraria; TG Therapeutics: Honoraria; Kite: Honoraria; Karyopharm: Honoraria; Atara: Consultancy, Honoraria; BMS: Research Funding; Merck: Research Funding. Muñoz: Seagen: Consultancy, Honoraria, Speakers Bureau; Pharmacyclics: Consultancy, Speakers Bureau; Bayer: Consultancy, Speakers Bureau; Kite, a Gilead Company: Consultancy, Speakers Bureau; Pfizer: Consultancy; Janssen: Consultancy, Speakers Bureau; Juno/Celgene: Consultancy; Bristol Myers Squibb: Consultancy; Alexion: Consultancy; BeiGene: Consultancy, Speakers Bureau; Fosunkite: Consultancy; Innovent: Consultancy; Debiopharma: Consultancy; Karyopharm: Consultancy; Genmab: Consultancy; ADC Therapeutics: Consultancy; Epizyme: Consultancy; Servier: Consultancy; Acrotech: Speakers Bureau; Verastem: Speakers Bureau; AstraZeneca: Speakers Bureau; Celgene/Bristol Myers Squibb: Speakers Bureau; Genentech: Speakers Bureau; Aurobindo: Speakers Bureau; Physicians' Education Resource: Honoraria; Kyowa Kirin: Consultancy, Honoraria, Speakers Bureau; OncView: Honoraria; Targeted Oncology: Honoraria. Westin: AstraZeneca: Consultancy, Research Funding; 47 Inc: Research Funding; Bristol Myers Squibb: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Kite, a Gilead Company: Consultancy, Research Funding; Morphosys: Research Funding; ADC Therapeutics: Consultancy, Research Funding; Umoja: Consultancy; Iksuda Therapeutics: Consultancy; MorphoSys: Consultancy, Research Funding; Curis: Research Funding; Genentech: Consultancy, Research Funding. Chavez: Bristol Myers Squibb: Speakers Bureau; Karyopharm Therapeutics: Consultancy; ADC Therapeutics: Membership on an entity's Board of Directors or advisory committees, Research Funding; Merck: Research Funding; Kite/Gilead: Consultancy; Abbvie: Consultancy; MorphoSys: Speakers Bureau; BeiGene: Speakers Bureau; Novartis: Consultancy; Adaptive: Research Funding; Epizyme: Speakers Bureau; AstraZeneca: Research Funding. Bennani: Kyowa Kirin: Other: Advisory Board; Daichii Sankyo Inc: Other: Advisory Board; Purdue Pharma: Other: Advisory Board; Verastem: Other: Advisory Board; Vividion: Consultancy, Other: Advisory Board. Vose: Kite, a Gilead Company: Honoraria, Research Funding. Miklos: Pharmacyclics: Patents & Royalties; Adaptive Biotechnologies, Novartis, Juno/Celgene-BMS, Kite, a Gilead Company, Pharmacyclics-AbbVie, Janssen, Pharmacyclics, AlloGene, Precision Bioscience, Miltenyi Biotech, Adicet, Takeda: Membership on an entity's Board of Directors or advisory committees; Kite, a Gilead Company, Amgen, Atara, Wugen, Celgene, Novartis, Juno-Celgene-Bristol Myers Squibb, Allogene, Precision Bioscience, Adicet, Pharmacyclics, Janssen, Takeda, Adaptive Biotechnologies and Miltenyi Biotechnologies: Consultancy; Pharmacyclics, Amgen, Kite, a Gilead Company, Novartis, Roche, Genentech, Becton Dickinson, Isoplexis, Miltenyi, Juno-Celgene-Bristol Myers Squibb, Allogene, Precision Biosciences, Adicet, Adaptive Biotechnologies: Research Funding. Neelapu: Takeda Pharmaceuticals and related to cell therapy: Patents & Royalties; Kite, a Gilead Company, Merck, Bristol Myers Squibb, Novartis, Celgene, Pfizer, Allogene Therapeutics, Cell Medica/Kuur, Incyte, Precision Biosciences, Legend Biotech, Adicet Bio, Calibr, Unum Therapeutics and Bluebird Bio: Honoraria; Kite, a Gilead Company, Bristol Myers Squibb, Merck, Poseida, Cellectis, Celgene, Karus Therapeutics, Unum Therapeutics (Cogent Biosciences), Allogene, Precision BioSciences, Acerta and Adicet Bio: Research Funding; Kite, a Gilead Company, Merck, Bristol Myers Squibb, Novartis, Celgene, Pfizer, Allogene, Kuur, Incyte, Precision BioSciences, Legend, Adicet Bio, Calibr, and Unum Therapeutics: Other: personal fees. Locke: GammaDelta Therapeutics: Consultancy, Other: Scientific Advisory Role; BMS/Celgene: Consultancy, Other: Scientific Advisory Role; Bluebird Bio: Consultancy, Other: Scientific Advisory Role; Calibr: Consultancy, Other: Scientific Advisory Role; Amgen: Consultancy, Other: Scientific Advisory Role; Allogene Therapeutics: Consultancy, Other: Scientific Advisory Role, Research Funding; Cellular Biomedicine Group: Consultancy, Other: Scientific Advisory Role; Wugen: Consultancy, Other; Takeda: Consultancy, Other; Novartis: Consultancy, Other, Research Funding; Umoja: Consultancy, Other; Cowen: Consultancy; EcoR1: Consultancy; Emerging Therapy Solutions: Consultancy; Gerson Lehrman Group: Consultancy; Moffitt Cancer Center: Patents & Royalties: field of cellular immunotherapy; Legend Biotech: Consultancy, Other; Janssen: Consultancy, Other: Scientific Advisory Role; Kite, a Gilead Company: Consultancy, Other: Scientific Advisory Role, Research Funding; Iovance Biotherapeutics: Consultancy, Other: Scientific Advisory Role. Dahiya: Kite, a Gilead Company: Consultancy; Atara Biotherapeutics: Consultancy; Miltenyi Biotech: Research Funding; Jazz Pharmaceuticals: Research Funding; BMS: Consultancy. Lunning: Spectrum: Consultancy; AstraZeneca: Consultancy; Acrotech: Consultancy; Legend: Consultancy; Novartis: Consultancy; Kyowa Kirin: Consultancy; Karyopharm: Consultancy; Morphosys: Consultancy; TG Therapeutics: Consultancy; Janssen: Consultancy; AbbVie: Consultancy; Verastem: Consultancy; Myeloid Therapeutics: Consultancy; Celgene, a Bristol Myers Squibb Co.: Consultancy; Daiichi-Sankyo: Consultancy; Beigene: Consultancy; ADC Therapeutics: Consultancy; Kite, a Gilead Company: Consultancy.

Abstract Introduction: Cytokine release syndrome (CRS) is a common toxicity associated with chimeric antigen receptor (CAR) T-cell therapies. Corticosteroids and steroid-sparing therapies such as tocilizumab, an interleukin-6 receptor antagonist, and anakinra, an interleukin-1 receptor antagonist, have been used to reduce the incidence and severity of these toxicities. Preclinical and clinical case studies of anakinra, administered subcutaneously or intravenously at various doses, have shown promising results in the management of CRS and systemic inflammatory responses resembling hemophagocytic lymphohistiocytosis (HLH)/macrophage activation syndrome (MAS). In CARTITUDE-1, CRS occurred in 95% of heavily pretreated patients with relapsed/refractory multiple myeloma (RRMM) receiving ciltacabtagene autoleucel (cilta-cel), a CAR T-cell therapy with 2 B-cell maturation antigen-targeting single-domain antibodies (Berdeja et al. Lancet 2021). Per protocol, tocilizumab was required to manage CRS with option to give steroids and/or anakinra per investigator discretion. Here, we report the institutional experiences of anakinra use in the management of CRS in patients who have received cilta-cel as part of the CARTITUDE-1 study. Methods: Eligible patients had MM and received ≥3 prior therapies or were refractory to a proteasome inhibitor (PI) and immunomodulatory drug (IMiD), and had received a PI, IMiD, and anti-CD38 antibody (Berdeja et al. Lancet 2021). After apheresis, bridging therapy was permitted. Patients received a single cilta-cel infusion (target dose: 0.75×10 6 CAR+ viable T cells/kg; range 0.5-1.0×10 6) 5-7 days after lymphodepletion (300 mg/m 2 cyclophosphamide, 30 mg/m 2 fludarabine daily for 3 days). Lee et al (Blood 2014) grading criteria for CRS were mapped to the ASTCT criteria for CRS. Post-hoc analysis of data revealed use of anakinra at some sites in patients who failed to respond to the initial management of CRS with tocilizumab +/- dexamethasone or in clinical settings where rise of ferritin and/or liver function tests were indicative for continued HLH/MAS-like manifestations (Kennedy et al. ASH 2020). Results: Of 97 patients in CARTITUDE-1, CRS occurred in 92 (95%) patients; 4% were grade 3/4. The median time to onset was 7 days (range 1-12) and median duration was 4 days (range 1-14). Supportive measures to treat CRS were administered to 91% of patients, most commonly tocilizumab (69%; 4 patients received ≥3 doses), corticosteroids (22%), and anakinra (18 patients, 19%). CRS resolved in 99% of patients. Anakinra was administered after initial tocilizumab and within the first 48 hours (range 0-6 days) of CRS onset for the majority of patients as part of effective management of CRS. Anakinra was administered at a dose of 100-200 mg every 8-12 hours over a median of 2.5 days (range 1-15 days). CRS uniformly resolved following anakinra use in CARTITUDE-1, apart from one patient who died from sepsis (grade 5 outcome) due to HLH/MAS considered related to treatment (Table). Conclusions: CRS events in cilta-cel-treated patients in CARTITUDE-1 were common, generally low-grade, and successfully managed with standard tocilizumab +/- dexamethasone. The use of anakinra should be considered in patients with persistent CRS/inflammatory symptoms despite tocilizumab use, and in particular in patients with HLH/MAS-like symptoms/phenotype occurring following CRS or in the absence of prior CRS. Figure 1 Figure 1. Disclosures Wong: Amgen: Consultancy; Genentech: Research Funding; Fortis: Research Funding; Janssen: Research Funding; GloxoSmithKlein: Research Funding; Dren Biosciences: Consultancy; Caelum: Research Funding; BMS: Research Funding; Sanofi: Membership on an entity's Board of Directors or advisory committees. Richard: Karyopharm, Janssen: Honoraria. Lin: Juno: Consultancy; Legend: Consultancy; Merck: Research Funding; Bluebird Bio: Consultancy, Research Funding; Sorrento: Consultancy; Janssen: Consultancy, Research Funding; Kite, a Gilead Company: Consultancy, Research Funding; Novartis: Consultancy; Celgene: Consultancy, Research Funding; Takeda: Research Funding; Gamida Cell: Consultancy; Vineti: Consultancy. Madduri: Janssen: Current Employment. Jackson: Janssen: Current Employment; Memorial Sloan Kettering Cancer Center: Consultancy. Zudaire: Janssen: Current Employment. Romanov: Janssen: Current Employment. Trigg: Janssen: Current Employment. Vogel: Janssen Global Services, LLC: Current Employment, Current holder of individual stocks in a privately-held company, Current holder of stock options in a privately-held company, Divested equity in a private or publicly-traded company in the past 24 months. Garrett: Legend Biotech USA: Current Employment. Nesheiwat: Legend Biotech USA: Current Employment. Martin: Oncopeptides: Consultancy; Sanofi: Research Funding; Janssen: Research Funding; GlaxoSmithKline: Consultancy; Amgen: Research Funding. Jagannath: Bristol Myers Squibb: Consultancy; Legend Biotech: Consultancy; Karyopharm Therapeutics: Consultancy; Janssen Pharmaceuticals: Consultancy; Takeda: Consultancy; Sanofi: Consultancy. OffLabel Disclosure: At the time of abstract submission, cilta-cel is being investigated for the treatment of multiple myeloma but is not yet approved

Abstract Introduction: Ciltacabtagene autoleucel (cilta-cel), a chimeric antigen receptor T-cell (CAR-T) therapy with 2 B-cell maturation antigen (BCMA)-targeting single-domain antibodies, is being evaluated in patients (pts) with relapsed/refractory multiple myeloma (RRMM). In the phase 1b/2 CARTITUDE-1 (NCT03548207) study, a single dose of cilta-cel led to early, deep, and durable responses in heavily pretreated pts with MM, with a manageable safety profile (Berdeja, Lancet, 2021). At median 18 months of follow-up, the overall response rate (ORR) was 98%, with 80% of pts achieving stringent complete response. Median duration of response (DOR) was 21.8 months (95% CI, 21.8-not estimable); 18-month progression-free survival (PFS) and overall survival (OS) rates were 66% and 81%, respectively. Here, we report the efficacy and safety of cilta-cel in various subgroups of pts in CARTITUDE-1. Methods: Eligible pts had MM and received ≥3 prior lines of therapy (LOT) or were double refractory to a proteasome inhibitor (PI) and immunomodulatory drug (IMiD), and had received a PI, IMiD, and anti-CD38 antibody. After apheresis, bridging therapy was permitted. Pts received a single cilta-cel infusion (target dose: 0.75×10 6 CAR+ viable T cells/kg; range 0.5-1.0×10 6) 5-7 days after lymphodepletion (300 mg/m 2 cyclophosphamide, 30 mg/m 2 fludarabine daily for 3 days). Primary objectives were to characterize cilta-cel safety, confirm the recommended phase 2 dose (phase 1b), and evaluate efficacy (phase 2). In this combined phase 1b and phase 2 analysis, cytokine release syndrome (CRS) graded by Lee et al (Blood 2014) criteria and neurotoxicity by CTCAE v5.0 were mapped to the ASTCT criteria for CRS and immune effector cell-associated neurotoxicity (ICANS), respectively. Efficacy and safety were evaluated in the following subgroups: ≥65 years of age, Black/African American, 3 prior LOT, ≥4 prior LOT, triple-class refractory, penta-drug refractory, standard- and high-risk cytogenetics, International Staging System stage III, bone marrow plasma cells at baseline (≤30%, >30 to <60%, and ≥60%), BCMA tumor expression at baseline (<80%, ≥80%), and presence of soft tissue plasmacytomas (bone-based and extramedullary). Results: As of February 11, 2021, 97 pts in the overall population received cilta-cel; 58.8% were male, median age was 61 years (range 43-78), and median time from diagnosis to enrollment was 5.9 years (range 1.6-18.2). ORR across all evaluated subgroups was comparable to the overall population, and was consistently high (range 95.1-100%) including in those with high-risk cytogenetics, ISS stage III MM, baseline bone marrow cells ≥60%, and baseline plasmacytomas (Table). Median DOR for most subgroups, including high-risk cytogenetics, was consistent with the overall population or not reached but was shorter in pts with ISS Stage III MM and baseline plasmacytomas (Table). Across all subgroups, 80%-100% of MRD-evaluable pts achieved MRD negativity (10 -5 threshold). 18-month PFS and OS rates were consistent with the overall population in most subgroups, including high-risk cytogenetics, and lower in ISS stage III and baseline plasmacytomas (Table). Incidence of CRS, ICANS, and other CAR T-cell neurotoxicities (events not reported as ICANS [ie, onset after a period of recovery from CRS and ICANS]) in various subgroups was consistent with the overall population, with no new safety signals. Conclusions: At median follow-up of 18 months, a single infusion of cilta-cel yielded deep, durable responses in all evaluated subgroups in CARTITUDE-1. An ORR of 95%-100% was observed in pts across all subgroups, including those with high-risk cytogenetics, ISS stage III MM, baseline bone marrow cells ≥60%, and baseline plasmacytomas. In patients with ISS stage III and with baseline plasmacytomas, median DOR appeared shorter and 18-mo PFS and OS rates lower. Cilta-cel safety profile across the subgroups was consistent with the overall population, with no new safety signals. Ongoing evaluation of cilta-cel in the multicohort CARTITUDE-2 (NCT04133636) study in pts with unmet need in varying stages of treatment for MM will further explore the treatment benefit of cilta-cel, including in those with high-risk disease. Figure 1 Figure 1. Disclosures Jakubowiak: GSK: Membership on an entity's Board of Directors or advisory committees; Abbvie: Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Sanofi: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees; Gracell: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees. Usmani: Janssen Oncology: Consultancy, Research Funding; Takeda: Consultancy, Research Funding, Speakers Bureau; SkylineDX: Consultancy, Research Funding; Sanofi: Consultancy, Research Funding, Speakers Bureau; Amgen: Consultancy, Research Funding, Speakers Bureau; Merck: Consultancy, Research Funding; Janssen: Consultancy, Research Funding, Speakers Bureau; Array BioPharma: Consultancy, Research Funding; GSK: Consultancy, Research Funding; Pharmacyclics: Consultancy, Research Funding; Seattle Genetics: Consultancy, Research Funding; Celgene/BMS: Consultancy, Research Funding, Speakers Bureau; EdoPharma: Consultancy; Abbvie: Consultancy; Bristol-Myers Squibb: Research Funding. Berdeja: Bluebird bio, BMS, Celgene, CRISPR Therapeutics, Janssen, Kite Pharma, Legend Biotech, SecuraBio, Takeda: Consultancy; GSK, Ichnos Sciences, Incyte: Research Funding; EMD Sorono, Genentech: Research Funding; Celularity, CRISPR Therapeutics: Research Funding; Lilly, Novartis: Research Funding; Abbvie, Acetylon, Amgen: Research Funding; Poseida, Sanofi, Teva: Research Funding. Cohen: Oncopeptides: Consultancy; Genentech/Roche: Consultancy; Janssen: Consultancy; BMS/Celgene: Consultancy; Takeda: Consultancy; GlaxoSmithKline: Consultancy, Research Funding; AstraZeneca: Consultancy; Novartis: Research Funding. Hari: Karyopharm: Consultancy; Adaptive Biotech: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Millenium: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding, Speakers Bureau; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding, Speakers Bureau; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding, Speakers Bureau; Celgene-BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding, Speakers Bureau; GSK: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding, Speakers Bureau; Oncopeptides: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Schecter: Janssen: Current Employment, Current holder of stock options in a privately-held company. Yeh: Janssen: Current Employment. Olyslager: Janssen: Current Employment. Banerjee: Janssen: Current Employment, Current holder of individual stocks in a privately-held company. Jackson: Janssen: Current Employment; Memorial Sloan Kettering Cancer Center: Consultancy. Allred: Janssen: Current Employment, Current holder of individual stocks in a privately-held company, Current holder of stock options in a privately-held company. Zudaire: Janssen: Current Employment. Deraedt: Janssen: Current Employment. Geng: Legend Biotech USA: Current Employment. Pacaud: Legend Biotech: Current Employment. Lin: Janssen: Consultancy, Research Funding; Vineti: Consultancy; Legend: Consultancy; Bluebird Bio: Consultancy, Research Funding; Novartis: Consultancy; Juno: Consultancy; Celgene: Consultancy, Research Funding; Kite, a Gilead Company: Consultancy, Research Funding; Takeda: Research Funding; Sorrento: Consultancy; Merck: Research Funding; Gamida Cell: Consultancy. Martin: Janssen: Research Funding; GlaxoSmithKline: Consultancy; Oncopeptides: Consultancy; Amgen: Research Funding; Sanofi: Research Funding. Jagannath: Bristol Myers Squibb: Consultancy; Janssen Pharmaceuticals: Consultancy; Legend Biotech: Consultancy; Karyopharm Therapeutics: Consultancy; Takeda: Consultancy; Sanofi: Consultancy. OffLabel Disclosure: At the time of abstract submission, cilta-cel is being investigated for the treatment of multiple myeloma but is not yet approved.