Hardy, Nancy M.

Background: Zamto-cel is an investigational autologous tandem CD20-CD19-directed non-cryopreserved CAR-T cell product administered as a fresh formulation to patients (pts) with relapsed/refractory Diffuse Large B Cell Lymphoma (r/r DLBCL) in the DALY II USA clinical trial (NCT04792489), a multicenter, open label, single-arm Phase 2 study. Here, we report efficacy and safety outcomes as part of a pre-planned interim analysis of 59 evaluable patients and 69 patients in the safety population. Methods: Eligible adults had r/r DLBCL after at least 2 prior lines of treatment including anti-CD20 monoclonal antibody and anthracycline-containing regimen and measurable disease per Lugano 2014 classification. Zamto-cel was manufactured utilizing CliniMACS Prodigy® (Miltenyi Biotec), a closed, automated system with a 14-day vein-to-vein time and administered as a fresh formulation. Lymphodepletion chemotherapy was initiated during the manufacturing process (either cyclophosphamide/ fludarabine or bendamustine) prior to receiving a single dose of zamto-cel at a dose of 2.5x106 CAR T cells/kg on Day 0. The primary endpoint was overall response rate (ORR) defined as best overall response (BOR) of either complete response (CR) or partial response (PR). Secondary endpoints included complete response rate (CRR), duration of response (DOR), progression-free survival (PFS), overall survival (OS), safety, and CD19 and CD20 antigen expression at relapse. Results: As of March 29th, 2024, 69 pts received zamto-cel of which 59 were evaluable having received a fresh, conforming product and completed a minimum of 3 months follow-up. Median age was 63 years (range 25-85), 39 (66%) were male. Sixteen pts (27%) received 3 or more lines of prior treatment. The majority of pts (53%) had elevated LDH at study entry, and 49% had ≥ 2 extranodal lesions, indicative of a study population with advanced disease. No pts received any bridging therapy, in the week after apheresis and before lymphodepletion. Only 7 pts (12%) received bendamustine as lymphodepleting regimen. Successful manufacturing of a fresh, in specification product occurred in 91.3% out of 69 treated pts. Four patients received a cryopreserved formulation to permit time for comorbid condition management. The mean viability of the final product was 96.0% with 29.4 % transduction efficacy. No patient died or withdrew during the manufacturing process. The ORR in the evaluable patient population (n=59) as assessed by an Independent Radiology Committee (IRC) was 72.9% (95% CI, 59.7-83.6), with a CRR of 49.2% (95% CI,35.9-62.5). The 6 month and 12 month-PFS was 55% (95%CI, 41-67) and 42% (95%CI, 28-56), respectively; 12 month-OS was 72% (95%CI, 57-83). The median DOR was 11.4 months. All 69 treated pts were assessed for safety outcomes. Treatment-emergent adverse events (TEAEs) were mostly of grade 1-2, the majority of grade ≥ 3 were hematological. Thirty-two pts (46.4%) experienced cytokine release syndrome (CRS), all grade 1-2. Immune effector cell-associated neurotoxicity syndrome (ICANS) was reported in 12 pts (17.4%), grade 1-2 (9 pts; 13.1%); grade 3 (3 pts; 4.3%). One patient experienced immune effector cell-associated hemophagocytic lymphohistiocytosis-like syndrome (IEC-HS), which resolved after 2 days. Biopsies at progression were available in 24 pts. CD19-negative relapse (defined as H Score <100) was seen in 2 pts, CD20-negative relapse was observed in 3 pts. Only one patient experienced loss of both antigens compared to pre-treatment status, demonstrating that most lymphomas maintain target antigen expression at relapse after treatment with zamto-cel. Conclusion: This pre-planned interim analysis represents the first pivotal trial of a tandem CD20-CD19 directed non-cryopreserved CAR-T cell product for patients with third-line r/r DLBCL. The trial plans to enroll 100 evaluable patients and the final data will be presented upon study completion. Among the 59 evaluable patients at the interim analysis, there is encouraging activity and a favorable safety profile in DLBCL patients treated with zamto-cel. Unlike currently registered CAR-T cell products, zamto-cel is administered as a fresh product with a short vein-to-vein time of 14 days with lymphodepletion initiated during the manufacturing process. With a manufacturing success rate of 91% we have demonstrated the feasibility of this process among high-risk patients with r/r DLBCL.

Abstract Background: Autologous stem cell transplantation (ASCT) in multiple myeloma (MM) has been shown to improve survival compared to conventional chemotherapy alone. However, the ability to perform ASCT relies, in part, on collecting a sufficient number (#) of CD34+ hematopoietic stem cells (HSCs), typically from peripheral blood. The ideal HSC mobilization regimen would enable collection of optimal #s of HSCs (5-6x10 6 CD34+ cells/kg) within the minimum # of apheresis sessions possible. Yet, despite currently available G-CSF (G) based mobilization regimens and multiple apheresis days, many remain unable to collect optimal #s of HSCs. Motixafortide (M) is a novel CXCR4 inhibitor, with high affinity (IC 50 0.54-4.5 nM) and long receptor occupancy (>48 hours). Methods: In this prospective, phase 3, double blind, placebo controlled, multicenter trial, 122 patients were randomized (2:1) to receive either M+G or placebo (P)+G for HSC mobilization prior to ASCT for MM. All patients received G (10 mcg/kg) on days 1-5 (and 6-8, if needed). Patients received either M (1.25 mg/kg, subcutaneous injection) or P on day 4 (and 6, if needed). Apheresis began day 5, with the primary (PEP) and secondary (SEP) endpoints of collecting ≥6x10 6 CD34+ cells/kg in up to 2 apheresis days or 1 day, respectively. Apheresis continued on days 6-8 if needed. Total CD34+ cells/kg were analyzed on site to determine if patients mobilized to the goal and all samples were subsequently sent for assessment by central laboratory. Patients that did not collect ≥2x10 6 CD34+ cells/kg by day 8 proceeded to rescue mobilization. The # of CD34+ cells infused was determined independently by each investigator according to local practice (minimum ≥2x10 6 CD34+ cells/kg). Analyses of the PEP/SEPs were performed on an intent-to-treat basis. Results: Demographics between the 2 treatment arms were similar. Mobilization with M+G resulted in 92.5% of patients collecting ≥6x10 6 CD34+ cells/kg within 2 apheresis days vs 26.2% with P+G (Odds Ratio (OR) 53.3, 95% CI 14.12-201.33, p<0.0001). Furthermore, 88.8% of patients with M+G collected ≥6x10 6 CD34+ cells/kg in 1 apheresis day vs 9.5% with P+G (OR 118.0, 95% CI 25.36-549.35, p<0.0001); and 96.3% with M+G collected ≥2x10 6 CD34+ cells/kg within 1 apheresis day vs 64.3% with P+G (OR 18.9, 95% CI 4.47-80.04, p<0.0001). The PEP and SEPs were confirmed as statistically significant by central laboratory (all respective p-values <0.0001). The median # of HSCs mobilized in 1 apheresis day with M+G was 10.80x10 6 CD34+ cells/kg vs 2.14x10 6 CD34+ cells/kg with P+G. The # of cells infused was determined independently by each investigator according to local practice. Median time to neutrophil engraftment was 12 days in both arms (HR 0.94, 95% CI 0.62-1.41, p=0.75). Median time to platelet engraftment was 18 days (range: 17-19) with M+G and 17 days (range: 17-18) with P+G (HR 0.89, 95% CI 0.59-1.34, p=0.57). Graft durability at day 100 post-ASCT was 92.2% in the M+G arm and 91.9% in the P+G arm (OR 1.04, 95% CI 0.2-4.5, p=0.96). Overall, adverse events were reported in 98.8% (Grade 3/4: 68.8%) of patients with M+G vs 95.2% (Grade 3/4: 42.9%) with P+G, with cytopenias in the post-ASCT period prior to engraftment accounting for the majority of Grade 3/4 AEs in both arms, as expected. The most common AEs related to M included: local injection site reactions (any grade: 70.0%, Grade 3/4: 11.3%); and systemic reactions such as pruritis (33.8%), flushing (32.5%) and urticaria (12.5%). Additionally, mobilization with M+G resulted in a 10.5x increase in mean absolute # of CD34+CD45RA-CD123loCD38-CD90+CD49f+ primitive HSCs collected vs P+G (p<0.0001). Multicolor FACS and scRNA sequencing of CD34+ HSCs from both arms will be reported in a separate ASH abstract. Conclusions: A single injection of M on top of G significantly increased the proportion of patients mobilizing ≥6x10 6 CD34+ cells/kg for ASCT (92.5%) vs G (26.2%) in up to 2 apheresis days (p<0.0001), while enabling 88.8% to collect ≥6x10 6 CD34+ cells/kg in just 1 apheresis (p<0.0001, Figure 1A). Despite the higher # of cells mobilized by M+G, the # of CD34+ cells/kg infused was determined independently by each investigator according to local practice with comparable engraftment kinetics and graft durability between the 2 arms. Finally, M+G mobilized 10.5x more immunophenotypically primitive CD34+ HSCs capable of durable multilineage hematopoietic engraftment vs P+G (p<0.0001, Figure 1B). Figure 1 Figure 1. Disclosures Crees: BioLineRx Ltd.: Research Funding. Larson: TORL biotherapeutics: Current holder of individual stocks in a privately-held company; Bioline: Research Funding; Abbvie: Research Funding; BMS: Research Funding; Celgene: Research Funding; GSK: Research Funding; Janssen: Research Funding; Juno: Research Funding; Novartis: Research Funding; Pfizer: Research Funding; Takeda: Research Funding. Illés: Pfizer: Consultancy, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees; Roche: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees. Stiff: Incyte: Research Funding; Cellectar: Research Funding; Seagen: Research Funding; Gamida Cell: Research Funding; Cellectar: Research Funding; Actinium: Research Funding; Bristol Myers Squibb: Research Funding; BioLineRX: Research Funding; Macrogenics: Research Funding; CRISPR Therapeutics: Consultancy, Honoraria; Amgen: Research Funding; Janssen: Research Funding; Kite, a Gilead Company: Research Funding; Karyopharm: Consultancy, Honoraria; MorphoSys: Consultancy, Honoraria. Sborov: Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees; GlaxoSmithKline: Consultancy; Sanofi: Consultancy; SkylineDx: Consultancy. Pereira: Jazz Pharmaceutical: Membership on an entity's Board of Directors or advisory committees. Mikala: Novartis: Consultancy; Takeda: Consultancy; Abbvie: Consultancy; Krka: Consultancy; Janssen: Consultancy; Amgen: Consultancy; Celgene: Consultancy. Holtick: Celgene: Honoraria; Sanofi: Honoraria. Qazilbash: Amgen: Research Funding; Oncopeptides: Other: Advisory Board; Bristol-Myers Squibb: Other: Advisory Board; Biolline: Research Funding; Angiocrine: Research Funding; NexImmune: Research Funding; Janssen: Research Funding. Hardy: American Gene Technologies, International: Membership on an entity's Board of Directors or advisory committees; Kite/Gilead: Membership on an entity's Board of Directors or advisory committees; InCyte: Membership on an entity's Board of Directors or advisory committees. Vainstein: BioLineRx LTD: Current Employment. Sorani: BioLineRx LTD: Current Employment. Gliko-Kabir: BioLineRx Ltd.: Current Employment. Goldstein: BioLineRx Ltd.: Current Employment. Kadosh: BioLineRx Ltd.: Current Employment.

Abstract Background: CD34+ hematopoietic stem and progenitor cell (HSPC) dose during hematopoietic cell transplantation (HCT) remains one of the most reliable clinical parameters to predict quality of engraftment. A minimum HSPC dose of 2-2.5x10 6 CD34+ cells/kg is considered necessary for reliable engraftment, while optimal doses of 5-6x10 6 CD34+ cells/kg are associated with faster engraftment, as well as fewer transfusions, infections, and antibiotic days. CXCR4 inhibition significantly improves the number (#) of CD34+ HSPCs mobilized for HCT, when added to G-CSF (G). Motixafortide (M), a novel CXCR4 antagonist, is a potent mobilizer of HSPCs recently evaluated in the phase 3, double blind, placebo controlled, multicenter GENESIS Trial as a mobilizing agent prior to autologous HCT (ASCT) in multiple myeloma (MM). Methods: Patients received G (10 mcg/kg) on days 1-5 (and days 6-8, if needed). On day 4 (and day 6, if needed), patients received either M (1.25 mg/kg) or placebo (P). Apheresis began day 5, with up to 4 days of apheresis if needed. The primary and secondary endpoints were collection of ³6x10 6 CD34+ cells/kg in up to 2 days of apheresis or 1 day, respectively. The # of CD34+ cells/kg infused was determined independently by each investigator according to local practice, but a minimum of ³2x10 6 CD34+ cells/kg was required. A post-hoc analysis was performed pooling data from both arms to evaluate time to platelet engraftment (TPE) (≥20x10 9/L without transfusions x7 days) and neutrophil engraftment (TNE) (ANC ≥0.5x10 9/L x3 days) based on total # of CD34+ cells/kg and # of specific CD34+ HSPC subsets infused. CD34+ HSPC immunophenotyping was performed via multicolor fluorescence-activated cell sorting (FACS). TPE/TNE was analyzed using Kaplan-Meier curves and Cox proportional hazards model. Results: 114 MM patients underwent apheresis, ASCT and were evaluable (M+G N=77; P+G N=37). M+G mobilization yielded a median of 10.8x10 6 CD34+ cells/kg collected in 1 apheresis vs 2.3x10 6 CD34+ cells/kg with P+G (p<0.0001). M+G also resulted in mobilization of higher #s of relevant CD34+ HSPC subsets vs P+G, including 5.6 fold more HSCs (CD45RA-CD123loCD38+CD90+CD49f+) (p<0.0001), 3.5 fold more multipotent progenitors (MPPs) and common myeloid progenitors (CMPs) (CD45RA-CD123loCD38+CD90-CD49f+) (p=0.0004) and 5.6 fold more granulocyte and macrophage progenitors (GMPs) (CD45RA+CD123loCD38+/-CD10-) (<0.0001). The median # of infused HSPCs in both arms was <6x10 6 CD34+ cells/kg (Table 1), with similar TPE of 17-18 days (HR 0.89, 95% CI 0.59-1.34, p=0.57) and TNE of 12 days (HR 0.94, 95% CI 0.62-1.41, p=0.75). However, pooled analysis of all patients (N=114) revealed infusion of ³6x10 6 CD34+ cells/kg was associated with faster median TPE of 16 days vs 18 days with <6x10 6 CD34+ cells/kg (HR 0.63, 95% CI 0.41-0.96, p=0.03) (Figure 1A). Further analysis demonstrated an inverse correlation between increasing CD34+ cells/kg infused and TPE (Pearson r=-0.2789, p=0.0027). In addition, pooled analysis of 36 patients (M+G N=24; P+G N=12) using extended multicolor FACS revealed infusion of higher #s (>75 th percentile) of combined CD34+ HSC, MPP, CMP and GMP subsets was associated with faster TPE of 12 days vs 19 days with lower #s of these subsets (p=0.003) (Figure 2A). Furthermore, higher #s (>75 th percentile) of GMPs was individually associated with faster TPE of 13 days vs 19 days with lower GMP cell doses (p=0.0116) (Figure 2C). TNE was not impacted by increasing doses of total CD34+ HSPCs or any specific CD34+ HSPC subset (all p>0.05) (Figures 1B, 2B and 2D). Conclusions: M+G mobilization enabled significantly more CD34+ cells to be collected in 1 apheresis (median 10.8x10 6 CD34+ cells/kg) vs P+G (2.3x10 6 CD34+ cells/kg), as well as 3.5-5.6 fold higher #s of HSCs, MPPs, CMPs and GMPs (all p-values <0.0004). This high # of CD34+ cells/kg mobilized with M+G enables the potential infusion of ≥6x10 6 CD34+ cells/kg and cryopreservation of cells for later use. A dose response was observed with significant correlation between faster TPE and infusion of higher #s of total CD34+ HSPC doses (³6x10 6 CD34+ cells/kg) and combined HSC, MPP, CMP and GMP subsets. Additionally, infusion of higher #s of CD34+ GMP subsets was independently associated with faster TPE, suggesting these more committed progenitors may play a critical role in early engraftment. Figure 1 Figure 1. Disclosures Crees: BioLineRx Ltd.: Research Funding. Retting: BioLineRx Ltd.: Research Funding. Larson: TORL biotherapeutics: Current holder of individual stocks in a privately-held company; Abbvie, Bioline, BMS, Celgene, GSK, Janssen, Juno, Novartis, Pfizer, Takeda: Research Funding. Illes: Novartis, Janssen, Pfizer, Roche: Other: Travel, Accommodations, Expenses; Takeda, Seattle Genetics: Research Funding; Janssen, Celgene, Novartis, Pfizer, Takeda, Roche: Consultancy. Stiff: CRISPR: Consultancy; Gamida-Cell, Atara, Amgen, Incyte, Takeda, Macrogenetics, Eisai: Research Funding. Sborov: SkylineDx: Consultancy; GlaxoSmithKline: Consultancy; Sanofi: Consultancy; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees. Pereira: Jazz Pharmaceutical: Membership on an entity's Board of Directors or advisory committees. Mikala: Abbvie: Consultancy; Amgen: Consultancy; Celgene: Consultancy; Janssen: Consultancy; Krka: Consultancy; Novartis: Consultancy; Takeda: Consultancy. Holtick: Sanofi: Honoraria; Celgene: Honoraria. Qazilbash: Janssen: Research Funding; Oncopeptides: Other: Advisory Board; Biolline: Research Funding; Bristol-Myers Squibb: Other: Advisory Board; NexImmune: Research Funding; Amgen: Research Funding; Angiocrine: Research Funding. Hardy: Kite/Gilead: Membership on an entity's Board of Directors or advisory committees; American Gene Technologies, International: Membership on an entity's Board of Directors or advisory committees; InCyte: Membership on an entity's Board of Directors or advisory committees. Sorani: BioLineRx LTD: Current Employment. Shemesh-Darvish: BioLineRx LTD: Current Employment. Vainstein: BioLineRx LTD: Current Employment; Enlivex: Consultancy. Kadosh: StatExcellence: Current holder of individual stocks in a privately-held company; BioLineRx: Honoraria.

AbstractBackgroundCD19-directed chimeric antigen receptor (CAR) T-cell therapy (CAR-T) has emerged as effective for relapsed/refractory large B-cell lymphoma (R/R LBCL). The neurologic toxicity seen with CAR-T, referred to as immune effector cell–associated neurotoxicity syndrome (ICANS), is poorly understood. To better elucidate the clinical characteristics, treatment outcomes, and correlative biomarkers of ICANS, we review here a single-center analysis of ICANS after CAR T-cell therapy in R/R LBCL.MethodsPatients (n = 45) with R/R LBCL treated with axicabtagene ciloleucel (axi-cel) were identified. Data regarding treatment course, clinical outcomes, and correlative studies were collected. Patients were monitored and graded for ICANS via CARTOX-10 scoring and Common Terminology Criteria for Adverse Events (CTCAE) v4.03 criteria, respectively.ResultsTwenty-five (56%) patients developed ICANS, 18 (72%) of whom had severe (CTCAE grades 3–4) ICANS. Median time to development of ICANS was 5 days (range, 3–11). Elevated pre-infusion (day 0 [D0]) fibrinogen (517 vs 403 mg/dL, upper limit of normal [ULN] 438 mg/dL, P = 0.01) and D0 lactate dehydrogenase (618 vs 506 units/L, ULN 618 units/L, P = 0.04) were associated with ICANS. A larger drop in fibrinogen was associated with ICANS (393 vs 200, P < 0.01). Development of ICANS of any grade had no effect on complete remission (CR), progression-free survival (PFS), or overall survival (OS). Duration and total dose of steroid treatment administered for ICANS did not influence CR, PFS, or OS.ConclusionsICANS after CAR-T with axi-cel for R/R LBCL was seen in about half of patients, the majority of which were high grade. Contrary to previous reports, neither development of ICANS nor its treatment were associated with inferior CR, PFS, or OS. The novel finding of high D0 fibrinogen level can identify patients at higher risk for ICANS.