Goyal, Lovely

2517 Background: Approximately 50% to 60% of pts with r/r LBCL will either not achieve a complete response (CR) or will relapse with current treatments and require additional therapy. Autologous anti-CD19 chimeric antigen receptor T (CAR T) therapies have revolutionized the care of patients whose disease progresses following standard therapies, but patient-specific manufacturing processes and long wait times to treatment present challenges for their broad clinical use. Allogeneic (healthy-donor-derived), off-the-shelf, anti-CD19 (CAR T) treatment promises broader and more rapid access to one-dose treatment with curative intent. Initial phase 1 data for the anti-CD19 AlloCAR T cell product ALLO-501 (NCT03939026) and successor, ALLO-501A (NCT04416984), demonstrated a manageable safety profile with no dose-limiting toxicities (DLTs), and efficacy comparable to autologous CAR T therapy in pts with r/r LBCL who were autologous CAR T-naïve. This update provides additional follow up and a focus on participants who received the conditioning regimen and cells made with an optimized manufacturing process currently under study in the first potentially pivotal trial for an allogeneic CAR T product. Methods: In these two multicenter, single-arm, open-label, phase 1 trials, a cohort of autologous CAR T-naïve pts with r/r LBCL underwent 3-day lymphodepletion (LD) with FCA90, fludarabine (F, 30 mg/m2/day), cyclophosphamide (C, 300 mg/m2/day), and ALLO-647 (A [anti-CD 52 mAb] 30 mg/day; total dose: 90 mg) followed by a single dose of ALLO-501 or ALLO-501A produced by the Alloy manufacturing process. Results: As of Jan 26, 2023, 12 pts received the FCA90 LD regimen and CAR T therapy with 100% receiving product per specifications with a median time from enrollment to LD of 3 days. Median follow-up time (actual) was 7.1 months (range: 1.4, 36.0). No DLTs, severe (Gr3+) cytokine-release syndrome (CRS), immune effector cell-associated neurotoxicity syndrome (ICANS), or graft-versus-host disease (GvHD) events occurred. An overall response rate and a CR rate of 66.7% and 58.3%, respectively, were observed. Median DOR was 23.1 months. Among 8 pts with the opportunity to be followed for 6 months, 5 (62.5%) had achieved CR and 4 (50.0%) sustained CR through 6 months. Analyses of vector copy number pharmacokinetics at Days 28 and 56 documented substantial and sustained expansion of CAR T cells. Conclusions: A one-time dose of allogeneic CAR T therapy following LD with FCA90 provided durable responses with a manageable safety profile in patients with r/r/ LBCL comparable to those treated with autologous CAR T cells. This treatment enables rapid access to off-the-shelf treatment with a median time from trial enrollment to treatment of 3 days. These findings support broader evaluation of ALLO-501A in the ongoing, first potentially pivotal phase 2 trial (ALPHA2) of off-the-shelf allogeneic CAR T cells. Clinical trial information: NCT03939026 .

Abstract Background Allogeneic (off the shelf) chimeric antigen receptor (CAR) T-cell therapy addresses the logistical challenges, availability (including insufficient T-cell yields from low baseline absolute lymphocyte count), and variable product quality of autologous CAR T therapy. ALLO-501A is a genetically modified anti-CD19 AlloCAR T™ cell product that uses TALEN ® gene editing to disrupt the T-cell receptor alpha constant gene (TRAC) and the CD52 gene to reduce the risk of graft-versus-host disease (GvHD) and permit the use of ALLO-647, an anti-CD52 monoclonal antibody (mAb), for selective and transitory host lymphodepletion (LD). Here we present an update on the preliminary safety, efficacy, and correlative data. ALLO-501A uses Cellectis technologies. Methods ALPHA2 (NCT04416984) is a single-arm, open-label, Phase 1/2 trial of ALLO-501A in patients (pts) with relapsed/refractory (R/R) large B-cell lymphoma (LBCL including [R/R] diffuse LBCL [DLBCL], transformed follicular lymphoma [tFL], marginal zone lymphoma [tMZL], primary mediastinal B-cell lymphoma [PMBCL], follicular lymphoma grade 3B [FL3B]) who received ≥2 prior lines of therapy (including an anthracycline and anti-CD20 mAb), have an ECOG performance status of 0 or 1. Subjects with donor specific antibodies are excluded. Following LD with ALLO-647, fludarabine 30 mg/m 2/d x 3d (F), and cyclophosphamide 300 or 500 mg/m 2/d x 3d (C), either a single (40 [DL1] or 120 [DL2] x 10 6 viable CAR T cells) or consolidation dose of ALLO-501A (DL2) are given. For consolidation dose, pts with ≥stable disease (SD) at day 28 receive consolidation with second ALLO-647 (no chemo) for LD and ALLO-501A (DL2) cell infusion. Results As of July 9, 2021, 20 pts were enrolled; 15 pts were treated with ALLO-501A (12 evaluable and 3 pending D28 assessment); 3 pts pending treatment; 2 pts withdrew due to adverse event (AE)/progressing disease (PD) prior to dosing. Patients were heavily pretreated with advanced-stage disease (Stage III: 4 [22.2%], Stage IV: 8 [44.4%]), median number of prior treatments was 3 with a high of 7. Three pts (16.7%) had primary refractory disease. Safety profile was manageable in both single dose and consolidation cohorts. Events of interest in the single dose cohort have been previously reported (ASCO 2021). In the consolidation cohort (13 enrolled, 9 pts dosed thus far), no cytokine release syndrome (CRS), no GvHD, no immune effector cell-associated neurotoxicity syndrome (ICANS), no dose-limiting toxicities (DLTs), no dose reductions, no Grade (Gr) 3+ infections and no related serious adverse events (SAEs) occurred, and infusion-related reactions were Gr 1. Among all treated, cytopenias were the most common AE and occurred in 72% of pts. Of the 12 evaluable pts (6 each treated in the single dose and consolidation dose cohort), both the overall response rate (ORR) and complete response (CR) were 50% (95% CI: 21.1, 78.9). In the consolidation cohort, both ORR and CR rate were 66.7% (95% CI: 22.3, 95.7) with 3/3 partial responses (PRs) converting to CR after consolidation; 1 pt had CR at days 28 and 56 post consolidation and 2 pts had PD at month 1 and did not receive consolidation. In single dose cohort, 2 pts have ongoing CR at 9 and 12+ months. CAR T expansion was greater in pts who achieved a CR with a geometric mean area under the curve (AUC) at D1-28 of 206,990 copies/ug*days (n=6; GSD 4.94) compared to pts who did not achieve a CR with AUC at D1-28 of 3,571 copies/ug*days (n=3; GSD 2.41). Pts who received the consolidation dose continued to have CAR T expansion after the 2 nd CAR T infusion with geometric mean AUC from D30-56 of 92,893 copies/ug*days (n=4; GSD 5.42). Conclusions ALLO-501A with consolidation dosing demonstrated comparable safety and an improved efficacy profile compared to single dosing with all 4 pts who received consolidation remaining in CR. Persistence of CAR T at D28 and expansion after consolidation dose was observed in addition to the observed deepening of responses in pts whose initial response was PR. Additional follow up is needed to determine whether consolidation also improves the durability of response. Consolidation was well tolerated and given the generally favorable overall safety profile, ALLO-501A may have the potential to be given in the outpatient setting. Enrollment is ongoing. Updated efficacy and follow-up will be presented at the meeting. Currently, an ALLO-501A Phase 2 trial is planned. Disclosures Locke: Cowen: Consultancy; Umoja: Consultancy, Other; Wugen: Consultancy, Other; Takeda: Consultancy, Other; Novartis: Consultancy, Other, Research Funding; Janssen: Consultancy, Other: Scientific Advisory Role; Bluebird Bio: Consultancy, Other: Scientific Advisory Role; BMS/Celgene: Consultancy, Other: Scientific Advisory Role; Calibr: Consultancy, Other: Scientific Advisory Role; Amgen: Consultancy, Other: Scientific Advisory Role; GammaDelta Therapeutics: Consultancy, Other: Scientific Advisory Role; Cellular Biomedicine Group: Consultancy, Other: Scientific Advisory Role; Kite, a Gilead Company: Consultancy, Other: Scientific Advisory Role, Research Funding; Legend Biotech: Consultancy, Other; Iovance Biotherapeutics: Consultancy, Other: Scientific Advisory Role; EcoR1: Consultancy; Allogene Therapeutics: Consultancy, Other: Scientific Advisory Role, Research Funding; Emerging Therapy Solutions: Consultancy; Gerson Lehrman Group: Consultancy; Moffitt Cancer Center: Patents & Royalties: field of cellular immunotherapy. Neelapu: 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, Merck, Bristol Myers Squibb, Novartis, Celgene, Pfizer, Allogene, Kuur, Incyte, Precision BioSciences, Legend, Adicet Bio, Calibr, and Unum Therapeutics: Other: personal fees; 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; Takeda Pharmaceuticals and related to cell therapy: Patents & Royalties. Hamadani: Janssen, Incyte, ADC Therapeutics, Omeros, Morphosys, Kite: Consultancy; Sanofi, Genzyme, AstraZeneca, BeiGene: Speakers Bureau; Takeda, Spectrum Pharmaceuticals and Astellas Pharma: Research Funding. Frank: Allogene Therapeutics: Research Funding; Kite-Gilead: Membership on an entity's Board of Directors or advisory committees; Adaptive Biotechnologies: Research Funding. Popplewell: Novartis: Other: Travel; Pfizer: Other: Travel; Hoffman La Roche: Other: Food. Abramson: Bluebird Bio: Consultancy; Kymera: Consultancy; BeiGene: Consultancy; Incyte Corporation: Consultancy; Astra-Zeneca: Consultancy; Allogene Therapeutics: Consultancy; Seagen Inc.: Research Funding; AbbVie: Consultancy; Karyopharm: Consultancy; Novartis: Consultancy; Morphosys: Consultancy; Kite Pharma: Consultancy; C4 Therapeutics: Consultancy; Genmab: Consultancy; EMD Serono: Consultancy; Bristol-Myers Squibb Company: Consultancy, Research Funding; Genentech: Consultancy. Munoz: Pharmacyclics/Abbvie: Consultancy, Research Funding, Speakers Bureau; Bayer: Consultancy, Research Funding, Speakers Bureau; Gilead/Kite Pharma: Consultancy, Research Funding, Speakers Bureau; Pfizer: Consultancy; Janssen: Consultancy, Research Funding, Speakers Bureau; Juno/Celgene: Consultancy, Research Funding, Speakers Bureau; BMS: Consultancy, Speakers Bureau; Kyowa: Consultancy, Honoraria, Speakers Bureau; Alexion: Consultancy; Beigene: Consultancy, Speakers Bureau; Fosunkite: Consultancy; Innovent: Consultancy; Seattle Genetics: Consultancy, Honoraria, Research Funding, Speakers Bureau; Debiopharm: Consultancy; Karyopharm: Consultancy; Genmab: Consultancy; ADC Therapeutics: Consultancy; Epizyme: Consultancy; Servier: Consultancy; Merck: Research Funding; Portola: Research Funding; Incyte: Research Funding; Genentech: Research Funding, Speakers Bureau; Millennium: Research Funding; Targeted Oncology: Honoraria; OncView: Honoraria; Physicians' Education Resource: Honoraria; Roche: Speakers Bureau; AstraZeneca: Speakers Bureau; Verastem: Speakers Bureau; Acrotech/Aurobindo: Speakers Bureau. Shin: Allogene Therapeutics, Inc.: Current Employment, Current equity holder in publicly-traded company. Loomis-Navale: Allogene: Current Employment, Current equity holder in publicly-traded company. Miklos: 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; 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; 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; Pharmacyclics: Patents & Royalties. OffLabel Disclosure: Discussion of fludarabine and cyclophosphamide in combination with ALLO-647 as conditioning regimen prior to administration of ALLO-501A in patients with R/R LBCL.

SummaryZUMA‐1 (NCT02348216) examined the safety and efficacy of axicabtagene ciloleucel (axi‐cel), an autologous CD19‐directed chimaeric antigen receptor (CAR)‐T cell therapy, in refractory large B‐cell lymphoma. To reduce treatment‐related toxicity, several exploratory safety management cohorts were added to ZUMA‐1. Specifically, cohort 6 investigated management of cytokine release syndrome (CRS) and neurologic events (NEs) with prophylactic corticosteroids and earlier corticosteroid and tocilizumab intervention. CRS and NE incidence and severity were primary end‐points. Following leukapheresis, patients could receive optional bridging therapy per investigator discretion. All patients received conditioning chemotherapy (days −5 through −3), 2 × 106 CAR‐T cells/kg (day 0) and once‐daily oral dexamethasone [10 mg, day 0 (before axi‐cel) through day 2]. Forty patients received axi‐cel. CRS occurred in 80% of patients (all grade ≤2). Any grade and grade 3 or higher NEs occurred in 58% and 13% of patients respectively. Sixty‐eight per cent of patients did not experience CRS or NEs within 72 h of axi‐cel. With a median follow‐up of 8·9 months, objective and complete response rates were 95% and 80% respectively. Overall, prophylactic corticosteroids and earlier corticosteroid and/or tocilizumab intervention resulted in no grade 3 or higher CRS, a low rate of grade 3 or higher NEs and high response rates in this study population.

Abstract ZUMA-3 is a phase 1/2 study evaluating KTE-X19, an autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy, in adult relapsed/refractory (R/R) B-cell acute lymphoblastic leukemia (B-ALL). We report the phase 1 results. After fludarabine-cyclophosphamide lymphodepletion, patients received a single infusion of KTE-X19 at 2 × 106, 1 × 106, or 0.5 × 106 cells per kg. The rate of dose-limiting toxicities (DLTs) within 28 days after KTE-X19 infusion was the primary end point. KTE-X19 was manufactured for 54 enrolled patients and administered to 45 (median age, 46 years; range, 18-77 years). No DLTs occurred in the DLT-evaluable cohort. Grade ≥3 cytokine release syndrome (CRS) and neurologic events (NEs) occurred in 31% and 38% of patients, respectively. To optimize the risk-benefit ratio, revised adverse event (AE) management for CRS and NEs (earlier steroid use for NEs and tocilizumab only for CRS) was evaluated at 1 × 106 cells per kg KTE-X19. In the 9 patients treated under revised AE management, 33% had grade 3 CRS and 11% had grade 3 NEs, with no grade 4 or 5 NEs. The overall complete remission rate correlated with CAR T-cell expansion and was 83% in patients treated with 1 × 106 cells per kg and 69% in all patients. Minimal residual disease was undetectable in all responding patients. At a median follow-up of 22.1 months (range, 7.1-36.1 months), the median duration of remission was 17.6 months (95% confidence interval [CI], 5.8-17.6 months) in patients treated with 1 × 106 cells per kg and 14.5 months (95% CI, 5.8-18.1 months) in all patients. KTE-X19 treatment provided a high response rate and tolerable safety in adults with R/R B-ALL. Phase 2 is ongoing at 1 × 106 cells per kg with revised AE management. This trial is registered at www.clinicaltrials.gov as #NCT02614066.

Background: Pts with high-risk LBCL have poor outcomes with R-CHOP chemoimmunotherapy (Sathyanarayanan, et al. ASH 2016. #106), and ≈50% of pts will not achieve long-term disease remission (Coiffier, et al. ASH Ed Program. 2016), highlighting unmet need for new therapies. Axi-cel, an autologous anti-CD19 chimeric antigen receptor (CAR) T cell therapy, was approved for treatment of adults with R/R LBCL after ≥ 2 lines of systemic therapies based on the pivotal study, ZUMA-1 (Neelapu SS, et al. NEJM. 2017). ZUMA-12 is a Phase 2, multicenter, open-label, single-arm study of axi-cel as part of first-line therapy in pts with high-risk LBCL. Here, we present interim efficacy, safety, and pharmacokinetics (PK) results from ZUMA-12. Methods: Eligible adults (≥ 18 y) met 2 criteria for high-risk LBCL: i) double- or triple-hit lymphoma by fluorescent in situ hybridization per investigator or LBCL with IPI score ≥ 3; and ii) positive interim PET per Lugano Classification (Cheson, et al. J Clin Oncol. 2014; Deauville score [DS] 4 or 5) after 2 cycles of an anti-CD20 monoclonal antibody and anthracycline containing regimen, which served as a dynamic risk assessment. Pts with PMBCL were not eligible. Pts underwent leukapheresis (≥ 2 wks after prior systemic therapy) and optional non-chemotherapy bridging at investigator discretion, followed by conditioning chemotherapy (cyclophosphamide 500 mg/m2/d and fludarabine 30 mg/m2/d for 3 d) and a single axi-cel infusion (target dose, 2 × 106 CAR T cells/kg). The primary endpoint was investigator-assessed complete response (CR) rate per Lugano. Key secondary endpoints included objective response rate (ORR), frequency of adverse events (AEs), and levels of CAR T cells and cytokines in blood and serum. Results: As of July 15, 2020, 31 pts have been enrolled and treated, and as of January 24, 2020, in a planned interim analysis, 15 pts were treated with axi-cel with ≥ 3 mos of follow-up. Median age was 60 y (range, 39 - 86), 67% of pts were male, 73% had ECOG of 1, 40%/60% had DS4/5; 60% had double- or triple-hit status per investigator, and 67% had IPI score ≥ 3. Baseline characteristics were largely comparable to ZUMA-1 Cohort 1 except for lower median tumor burden in ZUMA-12 (ZUMA-1: 3897 mm2 vs ZUMA-12: 1610 mm2). Of 12 response-evaluable pts (pts with centrally confirmed high-risk LBCL who received axi-cel), the investigator-assessed ORR was 92% (95% CI, 62% - 100%) with a CR rate of 75% (95% CI, 43% - 95%); 75% of pts had ongoing responses at data cutoff. Of 15 pts treated (safety analysis set), the investigator-assessed ORR was 93% (95% CI, 68% - 100%) with a CR rate of 80% (95% CI, 52% - 96%); 86% of pts had ongoing responses at data cutoff. Of 15 safety-evaluable pts, 80% experienced Grade ≥ 3 AEs. The most common Grade ≥ 3 AEs (≥ 25% of pts) were white blood cell count decreased (40%), anemia (27%), and encephalopathy (27%). Grade ≥ 3 cytokine release syndrome (CRS) and neurologic events (NEs) occurred in 20% and 27% of pts, respectively. All CRS and 10/11 NEs of any grade resolved (causally unrelated Grade 1 tremor was ongoing in 1 pt at data cutoff). Median time to onset of CRS was 4 d (range, 1 - 8), with median duration of 5 d (range, 2 - 12). Median time to onset of NEs was 9 d (range, 2 - 44), with median duration of 10 d (range, 1 - 40). Grade ≥ 3 infection was reported in 27% and Grade ≥ 3 neutrophil count decreased was reported in 20%. No Grade 5 AEs occurred. Despite similar assessment schedule and methodology, median peak CAR T cell levels were greater in ZUMA-12 vs ZUMA-1 Cohort 1 (131 cells/µL [range, 10 - 555] vs 32 cells/µL [range, 1 - 1514]). Median CAR T cell expansion (AUC0-28) was also greater in ZUMA-12 (1124 cells/µL × d [range, 147 - 4261]; ZUMA-1: 357 cells/µL × d [range, 5 - 11,507]). Median time to peak levels of CAR T cells in blood was 7 d after infusion. PK were similar in pts with double- or triple-hit lymphoma and IPI score ≥ 3. Updated safety, efficacy, and PK results will be reported, along with product characteristics and levels of key cytokines. Conclusion: ZUMA-12 is the first study evaluating CAR T cell therapy as first-line therapy in high-risk LBCL, which notably was defined by both histology and/or IPI and dynamic risk assessment with PET scan. Axi-cel demonstrated significant clinical benefit, with high ORR and CR rates and a manageable safety profile in pts for whom there is an unmet medical need. The study also provides new insights into the pharmacology of CAR T cell therapy for pts exposed to fewer prior therapies. Disclosures Neelapu: Pfizer: Other: personal fees; Bristol-Myers Squibb: Other: personal fees, Research Funding; Merck: Other: personal fees, Research Funding; Kite, a Gilead Company: Other: personal fees, Research Funding; N/A: Other; Adicet Bio: Other; Poseida: Research Funding; Unum Therapeutics: Other, Research Funding; Celgene: Other: personal fees, Research Funding; Novartis: Other: personal fees; Allogene Therapeutics: Other: personal fees, Research Funding; Takeda Pharmaceuticals: Patents & Royalties; Precision Biosciences: Other: personal fees, Research Funding; Cell Medica/Kuur: Other: personal fees; Incyte: Other: personal fees; Acerta: Research Funding; Karus Therapeutics: Research Funding; Cellectis: Research Funding; Legend Biotech: Other; Calibr: Other. Dickinson:Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Gilead: Consultancy, Honoraria, Research Funding, Speakers Bureau; Merck Sharp & Dohme: Consultancy; Novartis: Consultancy, Honoraria, Research Funding, Speakers Bureau; Janssen: Consultancy, Honoraria, Speakers Bureau. Oluwole:Spectrum Pharmaceuticals: Consultancy; Bayer: Consultancy; Kite, a Gilead Company: Consultancy, Honoraria, Research Funding; Pfizer: Consultancy. Herrera:Genentech, Inc./F. Hoffmann-La Roche Ltd: Consultancy, Research Funding; Pharmacyclics: Research Funding; Merck: Consultancy, Research Funding; Bristol Myers Squibb: Consultancy, Other: Travel, Accomodations, Expenses, Research Funding; Immune Design: Research Funding; AstraZeneca: Research Funding; Gilead Sciences: Consultancy, Research Funding; Seattle Genetics: Consultancy, Research Funding; Karyopharm: Consultancy. Thieblemont:Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company); Bayer: Honoraria; AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company); Kite, a Gilead Company: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company); Cellectis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company), Speakers Bureau; Incyte: Honoraria; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel support; Bristol-Myers Squibb: Consultancy, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company); Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company); Hospira: Research Funding; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company), Research Funding. Ujjani:AstraZeneca: Consultancy, Honoraria, Research Funding; Abbvie: Consultancy, Honoraria, Research Funding; Verastem Oncology: Consultancy, Honoraria; Gilead/Kite: Consultancy, Research Funding; Atara: Consultancy, Honoraria; Genentech: Consultancy, Honoraria; MorphoSys: Consultancy. Lin:Sorrento: Consultancy, Membership on an entity's Board of Directors or advisory committees; Vineti: Consultancy; Gamida Cells: Consultancy; Kite, a Gilead Company: Consultancy, Research Funding; Takeda: Research Funding; Merck: Research Funding; Legend BioTech: Consultancy; Juno: Consultancy; Bluebird Bio: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Novartis: Consultancy; Janssen: Consultancy, Research Funding. Riedell:Celgene/Bristol-Myers Squibb: Consultancy, Research Funding; Novartis Pharmaceuticals: Consultancy, Honoraria, Research Funding; Karyopharm Therapeutics: Consultancy; Bayer: Consultancy, Speakers Bureau; Kite/Gilead: Research Funding, Speakers Bureau; MorphoSys: Research Funding. Kekre:Gilead: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Celgene: Consultancy, Honoraria. de Vos:Bayer: Consultancy; Verastem: Consultancy. Yang:Kite, a Gilead Company: Current Employment. Milletti:Kite, a Gilead Company: Current Employment; Gilead Sciences: Other: stock or other ownership . Goyal:Kite, a Gilead Company: Current Employment. Kawashima:Kite, a Gilead Company: Current Employment; Gilead Sciences: Other: stock or other ownership . Chavez:Merck: Research Funding; Morphosys: Consultancy, Speakers Bureau; AstraZeneca: Speakers Bureau; Celgene: Consultancy; Novartis: Consultancy; Kite, a Gilead Company: Consultancy, Speakers Bureau; Genentech: Speakers Bureau; Epizyme: Speakers Bureau; Gilead: Consultancy; Bayer: Consultancy; BeiGene: Speakers Bureau; Karyopharm: Consultancy; AbbVie: Consultancy; Verastem: Consultancy; Pfizer: Consultancy.

Background: Axi-cel, an autologous anti-CD19 chimeric antigen receptor (CAR) T cell therapy, is approved for treatment of adult pts with R/R LBCL after ≥ 2 lines of systemic therapy. In the pivotal ZUMA-1 study, axi-cel demonstrated durable responses and a largely manageable safety profile (Locke FL, et al. Lancet Oncol. 2019). ZUMA-9 (NCT03153462), a multicenter, open-label study, provided pts with R/R LBCL with expanded access to axi-cel until commercial availability (Cohort 1 [C1]) and later, if commercially manufactured product did not meet commercial release specification(s) (Cohort 2 [C2]). Safety and efficacy of axi-cel (C1 and C2) and translational analyses (C2) are presented. Methods: Eligible adults had histologically confirmed R/R LBCL, ECOG ≤ 1, and received prior CD20-targeting and an anthracycline-containing regimen. C2 pts must have had commercial OOS product. Pts underwent leukaphersis and conditioning chemotherapy (cyclophosphamide 500 mg/m2/day and fludarabine 30 mg/m2/day) for 3 days followed by a single axi-cel infusion (target dose, 2 × 106 CAR T cells/kg). C1 and C2 pts with high disease burden could receive bridging therapy before conditioning at investigator's discretion. Endpoints included frequency of adverse events (AEs), objective response rate (ORR) per standard-of-care imaging assessment, overall survival (OS) for C1 and C2, and blood CAR T cells levels and serum cytokines for C2 only. Outcomes were contextualized with the primary analysis of ZUMA-1 C1+2 (n = 101; ≥ 6 mo of follow-up; Neelapu SS, et al. NEJM. 2017). Results: As of 11/29/2019 (C1) and 3/15/2020 (C2), 25 C1 pts and 36 C2 pts received axi-cel with a median follow-up of 27.1 mo (range, 23.6 - 29.6) and 13.2 mo (range, 0.4 - 25.7), respectively. In C1, median age was 56 y (range, 28 - 76), 60% were male, 80% had DLBCL, 48%/0% had ECOG1/≥2, 44% had IPI ≥3, and 64% had ≥ 3 prior lines of therapy. In C2, median age was 61 y (range, 24 - 81), 75% were male, 78% had DLBCL, 58%/17% had ECOG 1/≥2, 56% had IPI ≥3, and 69% had ≥ 3 prior lines of therapy. In C2, 50% of pts had OOS product with low viability, 28% had high IFN-γ, 14% had low IFN-γ, 14% received a low dose, and 6% had high transduction ratio. The ORR was 76% (64% complete response [CR]) for C1, 53% (36% CR) for C2, and 82% (54% CR) for ZUMA-1 C1+2. Median OS was 23.8 mo (95% CI, 13.5 - NE) for C1 and not reached (95% CI, 3.4 - NE) for C2, respectively. ORR and OS were consistent in C2 OOS subgroups (Table). Grade ≥ 3 AEs were reported in 88% and 89% of C1 and C2 pts, respectively. Grade ≥ 3 CRS (Lee et al, Blood. 2014) was not observed in C1 but was reported in 3% of C2 pts (13% in ZUMA-1 C1+2). Grade ≥ 3 neurologic events (NEs) occurred in 36% and 19% of pts in C1 and C2, respectively, and 28% of pts in ZUMA-1 C1+2. No Grade 5 CRS or NEs occurred in C1 or C2. All CRS and NEs resolved in C1, and most CRS (29/30) and NEs (19/24) resolved in C2 as of the data cutoff. Of 3 Grade 5 AEs in C1, 2 were unrelated to axi-cel (clostridial sepsis [on Day (D) 6] and respiratory failure [on D212]) and 1 was related to conditioning (myelodysplastic syndrome [on D563]). Of 3 Grade 5 AEs in C2, 2 were unrelated to axi-cel (multiple organ dysfunction syndrome [on D6] and cardiac arrest [on D482]) and 1 was related to axi-cel (systemic mycosis [on D30]). Median peak CAR T cell levels and median CAR T cell expansion (area under the curve in the first 28 days) were lower in ZUMA-9 C2 (n = 32/36; 12 cells/µL [range, 0 - 442] and 112 cells/µL × days [range, 0 - 3413]) vs ZUMA-1 C1+2 (n = 96/101; 42 cells/µL [range, 1 - 1514] and 462 cells/µL × days [range, 5 - 14,329]). Serum IFN-γ levels peaked within 8 days after axi-cel infusion (median, 170 pg/mL [range, 8 - 1876]) and were lower vs ZUMA-1 C1+2 (median, 477 pg/mL [range, 8 - 8209]). Axi-cel in ZUMA-9 C2 contained fewer, less differentiated CCR7+ naïve and central memory T cells, and a greater proportion of more differentiated CCR7- effector memory and effector T cells vs ZUMA-1 C1+2. No cases of replication-competent retroviruses were reported in C1 or C2. Conclusion: Axi-cel treatment demonstrated a manageable safety profile and meaningful clinical benefit in this expanded access and OOS product study. While CAR T cell therapy showed clinical benefit in C2 (OOS product), the lower CR rate was corroborated by lower CAR T cell expansion and a more differentiated product vs ZUMA-1 C1+2, warranting further investigation. ZUMA-9 C2 is enrolling pts and evaluation is ongoing. Disclosures Jacobson: Precision Biosciences: Consultancy, Honoraria, Other: travel support; Celgene/BMS: Consultancy, Honoraria, Other: travel support; Novartis: Consultancy, Honoraria, Other: travel support; AXIS: Speakers Bureau; Nkarta: Consultancy, Honoraria, Other: travel support; Clinical Care Options: Speakers Bureau; Pfizer: Research Funding; Lonza: Consultancy, Honoraria, Other: travel support; Kite, a Gilead Company: Consultancy, Honoraria, Other: travel support. Locke:Calibr: Consultancy; Kite, a Gilead Company: Consultancy, Research Funding; Wugen: Consultancy; GammaDelta Therapeutics: Consultancy; Celgene/Bristol-Myers Squibb: Consultancy; Novartis: Consultancy; Cellular Biomedicine Group: Other: Consultancy with grant options; Allogene: Consultancy. Miklos:Adaptive Biotech: Consultancy, Other: Travel support, Research Funding; Novartis: Consultancy, Other: Travel support, Research Funding; Pharmacyclics: Consultancy, Other: Travel support, Patents & Royalties, Research Funding; Juno-Celgene-Bristol-Myers Squibb: Consultancy, Other: Travel support, Research Funding; Allogene Therapeutics Inc.: Research Funding; Miltenyi Biotec: Research Funding; Janssen: Consultancy, Other: Travel support; Kite-Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Travel support, Research Funding. Vose:Incyte: Research Funding; Novartis: Research Funding; Bristol-Myers Squibb: Research Funding; Karyopharm Therapeutics: Consultancy, Honoraria; Allogene: Honoraria; Loxo: Consultancy, Honoraria, Research Funding; Seattle Genetics: Research Funding; Miltenyi Biotec: Honoraria; Janssen: Honoraria; Epizyme: Honoraria, Research Funding; AbbVie: Consultancy, Honoraria; Kite, a Gilead Company: Honoraria, Research Funding; AstraZeneca: Consultancy, Honoraria, Research Funding; Verastem: Consultancy, Honoraria; Wugen: Honoraria; Celgene: Honoraria; Roche/Genetech: Consultancy, Honoraria, Other. Lin:Sorrento: Consultancy, Membership on an entity's Board of Directors or advisory committees; Merck: Research Funding; Vineti: Consultancy; Gamida Cells: Consultancy; Takeda: Research Funding; Kite, a Gilead Company: Consultancy, Research Funding; Legend BioTech: Consultancy; Juno: Consultancy; Bluebird Bio: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Novartis: Consultancy; Janssen: Consultancy, Research Funding. Budde:Roche: Consultancy; Merck: Research Funding; Amgen: Research Funding; Kite, a Gilead Company: Consultancy; Gilead Sciences: Consultancy; Mustang Therapeutics: Research Funding; AstraZeneca: Research Funding. Maloney:Celgene: Consultancy, Honoraria, Research Funding; A2 Biotherapeutics: Consultancy, Current equity holder in publicly-traded company, Honoraria; Gilead Sciences: Consultancy, Honoraria; Juno Therapeutics: Consultancy, Honoraria, Patents & Royalties: Patents are pending, but not issued, licensed, no royalties, no licensees., Research Funding; Bioline Rx: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Pharmacyclics: Consultancy, Honoraria; MorphoSys: Consultancy, Honoraria; Genentech: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; Kite, a Gilead Company: Consultancy, Honoraria, Research Funding. Jaglowski:Juno: Consultancy; Kite, a Gilead Company: Consultancy, Research Funding; CRISPR: Consultancy; Novartis: Consultancy, Research Funding. Riedell:MorphoSys: Research Funding; Kite/Gilead: Research Funding, Speakers Bureau; Bayer: Consultancy, Speakers Bureau; Karyopharm Therapeutics: Consultancy; Celgene/Bristol-Myers Squibb: Consultancy, Research Funding; Novartis Pharmaceuticals: Consultancy, Honoraria, Research Funding. Perales:Celgene: Honoraria; MolMed: Membership on an entity's Board of Directors or advisory committees; Omeros: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bellicum: Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Honoraria, Membership on an entity's Board of Directors or advisory committees; Kite/Gilead: Honoraria, Research Funding; Miltenyi Biotec: Research Funding; Merck: Consultancy, Honoraria; Nektar Therapeutics: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Cidara Therapeutics: Other; Servier: Membership on an entity's Board of Directors or advisory committees, Other; Medigene: Membership on an entity's Board of Directors or advisory committees, Other; NexImmune: Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; Incyte Corporation: Honoraria, Research Funding. Kim:Gilead Sciences: Current equity holder in publicly-traded company; Kite, a Gilead Company: Current Employment. Kawashima:Kite, a Gilead Company: Current Employment; Gilead Sciences: Other: stock or other ownership . Yang:Kite, a Gilead Company: Current Employment. Rossi:Kite, a Gilead Company: Current Employment; Gilead Sciences: Current equity holder in publicly-traded company. Goyal:Kite, a Gilead Company: Current Employment. Neelapu:Legend Biotech: Other; Allogene Therapeutics: Other: personal fees, Research Funding; Cell Medica/Kuur: Other: personal fees; Incyte: Other: personal fees; Unum Therapeutics: Other, Research Funding; Adicet Bio: Other; Novartis: Other: personal fees; Bristol-Myers Squibb: Other: personal fees, Research Funding; Merck: Other: personal fees, Research Funding; Kite, a Gilead Company: Other: personal fees, Research Funding; Precision Biosciences: Other: personal fees, Research Funding; Poseida: Research Funding; Calibr: Other; Acerta: Research Funding; Takeda Pharmaceuticals: Patents & Royalties; Celgene: Other: personal fees, Research Funding; Pfizer: Other: personal fees; Karus Therapeutics: Research Funding; Cellectis: Research Funding; N/A: Other.

TPS7574 Background: Pts with LBCL who have persistent disease assessed by dynamic PET after rituximab-based induction therapy have an increased risk of death (Casasnovas, et al. Blood. 2017). Axi-cel is an autologous anti-CD19 chimeric antigen receptor (CAR) T cell therapy approved for the treatment of pts with relapsed/refractory LBCL with ≥ 2 prior systemic therapies. In ZUMA-1, the registrational study of axi-cel in pts with refractory LBCL, the objective response rate (ORR) was 91% (70% complete response [CR] rate) in pts with double-expressor or high-grade LBCL with ongoing responses in 48% after a median follow-up of 27.1 mos (Locke FL, et al. Lancet Oncol 2019). Furthermore, pts with fewer prior lines of therapy and lower tumor burden had higher rates of ongoing responses and manageable safety (Locke et al. ASCO 2018. 3039). ZUMA-12 will investigate the efficacy and safety of axi-cel as a first-line therapy in newly diagnosed pts with high-risk LBCL who have PET-positive disease after 2 cycles of induction therapy. Methods: This Phase 2 study has a planned enrollment of ≈40 pts aged ≥ 18 y with high-risk LBCL, defined by the presence of MYC and BCL2 and/or BCL6 translocations by FISH or an IPI score ≥ 3 any time before enrollment, and an ECOG performance status of 0 – 1. Before enrollment, pts must have a Deauville score of 4 – 5 (Barrington SF et al. J Clin Oncol. 2014) after 2 cycles of chemoimmunotherapy that includes an anti-CD20 monoclonal antibody and anthracycline. After leukapheresis, pts with bulky or rapidly progressing disease may receive optional non-chemotherapy bridging therapy. Following conditioning therapy with cyclophosphamide (500 mg/m2) and fludarabine (30 mg/m2) for 3 days, pts will receive a single infusion of axi-cel at a target dose of 2 × 106 CAR T cells/kg. The primary endpoint is investigator-assessed CR rate per the Lugano classification (Cheson et al. J Clin Oncol. 2014). Key secondary endpoints include ORR, duration of response, event-free survival, progression-free survival, overall response, safety, relapse with CNS disease and levels of blood CAR T cells and serum cytokines over time. Accrual is ongoing. Clinical trial information: NCT03761056.

7006 Background: KTE-X19 is an autologous anti-CD19 CAR T cell therapy under investigation for adult R/R ALL. In an interim analysis of Phase 1 of ZUMA-3, we reported manageable safety and encouraging efficacy of KTE-X19; 72% of pts achieved a complete remission (CR) or CR with incomplete bone marrow (BM) recovery (CRi; Wierda et al, ASH 2018. #897). Here, we present end of Phase 1 results. Methods: Adults with R/R B cell ALL, > 5% BM blasts, and ECOG 0-1 received 2, 1, or 0.5 × 106 KTE-X19 cells/kg after conditioning chemotherapy. Revised adverse event management (rAE mgmt) was implemented for additional pts in a 1 × 106 dose cohort: corticosteroids were given earlier at onset of Grade ≥ 2 neurologic events (NEs) and tocilizumab was used only for active toxicity. The primary endpoint was the dose-limiting toxicity (DLT) rate. Key additional endpoints were KTE-X19 levels, incidence of AEs, minimal residual disease (MRD), and CR/CRi rate. Results: As of 9/27/18, 45 pts had received KTE-X19 (median follow-up [f/u], 16 mo). The median age was 46 y (range, 18–77); 30 pts (66%) had ≥ 3 prior therapies and the median pre-conditioning BM blasts was 70% (range, 0–97). Six, 23, and 16 pts received 2, 1, and 0.5 × 106 cells/kg, respectively. There were no DLTs in the DLT-evaluable pts. The most common Grade ≥ 3 AEs were hypotension (38%), pyrexia (38%) and thrombocytopenia (31%). There were 2 previously reported KTE-X19–related Grade 5 AEs of cerebral infarction and multiorgan failure, both in the context of CRS. Grade ≥ 3 CRS and NEs occurred in 13 (29%) and 17 (38%) pts, respectively. Of 41 pts with ≥ 2 mo of f/u, 68% had CR/CRi, and 73% had undetectable MRD. Of 19 pts with ≥ 2 mo of f/u treated with 1 × 106 cells/kg, 16 (84%) had a CR/CRi and the median event-free survival was 15 mo. In 9 pts treated with 1 × 106 cells/kg and rAE mgmt, 2 (22%) had Grade 3 CRS and 1 (11%) had Grade 3 NE with no Grade 4/5 events. Conclusions: KTE-X19 dosing and safety mgmt have been successfully refined by testing 3 cell doses and evaluating a new AE mgmt guideline with altered corticosteroids/tocilizumab use for NE/CRS. Pivotal Phase 2 is ongoing at the 1 × 106 dose with rAE mgmt. Clinical trial information: NCT02614066.