anti-CD19 CAR Research Articles

CAR T-cell Therapy for Central Nervous System Lymphoma.

While anti-CD19 CAR T-cell therapy represents a major advance in systemic diffuse large B-cell lymphomas, central nervous system (CNS) lymphomas have been excluded from pivotal trials because of the fear of neurotoxicity. The purpose of this review was to assess the efficacy and tolerance of CAR T-cells in CNS lymphomas based on recently published studies. All the studies on CAR T-cell therapy for both primary and secondary CNS lymphomas reported high response rates (complete response rates ranging from 32 to 67%) in highly pre-treated patients. One-year PFS reached 40 to 60% in several studies. Neurotoxicity occurred in 36 to 68% of patients, including grade 3-4 neurotoxicity in 4.5 to 29% of patients. CAR T-cell therapy appears to be a very promising treatment in CNS lymphomas, with efficacy results close to those observed in systemic lymphomas. The toxicity profile, notably regarding neurotoxicity, is reassuring and should not prevent the development of CAR T-cells in the disease.

Safe and potent anti-CD19 CAR T-cells with shRNA-IL-6 gene silencing element in patients with refractory or relapsed B-cell acute lymphoblastic leukemia.

Severe cytokine release syndrome (sCRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) have limited the widespread use of chimeric antigen receptor T (CAR T)-cell therapy. We designed a novel anti-CD19 CAR (ssCART-19) with a small hairpin RNA (shRNA) element to silence the interleukin-6 (IL-6) gene, hypothesizing it could reduce sCRS and ICANS by alleviating monocyte activation and proinflammatory cytokine release. In a post hoc analysis of two clinical trials, we compared ssCART-19 with common CAR T-cells (cCART-19) in relapsed/refractory B-cell acute lymphoblastic leukemia (r/r B-ALL). Among 87 patients, 47 received ssCART-19 and 40 received cCART-19. Grade ≥3 CRS occurred in 14.89% (7/47) of the ssCART-19 group versus 37.5% (15/40) in the cCART-19 group (p = 0.036). ICANS occurred in 4.26% (2/47) of the ssCART-19 group (all grade 1) compared to 15% (2/40) of the cCART-19 group. Patients in the ssCART-19 group showed comparable rates of treatment response (calculated with rates of complete remission and incomplete hematological recovery) were 91.49% (43/47) for ssCART-19 and 85% (34/40) for cCART-19 (p = 0.999). With a median follow-up of 21.9 months, cumulative nonrelapse mortality was 10.4% for ssCART-19 and 13.6% for cCART-19 (p = 0.33). Median overall survival was 37.17 months for ssCART-19 and 32.93 months for cCART-19 (p = 0.40). Median progression-free survival was 24.17 months for ssCART-19 and 9.33 months for cCART-19 (p = 0.23). These data support the safety and efficacy of ssCART-19 for r/r B-ALL, suggesting its potential as a promising therapy.

Clinical Evaluation of Fast-in-Time (FIT) Anti-CD19 CAR T—A Non-Viral, 2-Day Rapid Manufacture CAR T-Cell Therapy for B-Cell Malignancies

Clinical Evaluation of Fast-in-Time (FIT) Anti-CD19 CAR T—A Non-Viral, 2-Day Rapid Manufacture CAR T-Cell Therapy for B-Cell Malignancies

Third-generation anti-CD19 CAR T cells for relapsed/refractory chronic lymphocytic leukemia: a phase 1/2 study

Third-generation chimeric antigen receptor T cells (CARTs) for relapsed or refractory (r/r) chronic lymphocytic leukemia (CLL) may improve efficacy compared to second-generation CARTs due to their enhanced CAR design. We performed the first phase 1/2 investigator-initiated trial evaluating escalating doses of third-generation CARTs (HD-CAR-1) targeting CD19 in patients with r/r CLL and B-cell lymphoma. CLL eligibility criteria were failure to two therapy lines including at least one pathway inhibitor and/or allogeneic hematopoietic cell transplantation. Nine heavily pretreated patients received HD-CAR-1 at dose levels ranging from 1 × 106 to 200 × 106 CART/m2. In-house HD-CAR-1 manufacturing was successful for all patients. While neurotoxicity was absent, one case of grade 3 cytokine release syndrome was observed. By day 90, six patients (67%) attained a CR, five of these (83%) with undetectable MRD. With a median follow-up of 27 months, 2-year PFS and OS were 30% and 69%, respectively. HD-CAR-1 products of responders contained significantly more CD4 + T cells compared to non-responders. In non-responders, a strong enrichment of effector memory-like CD8 + T cells with high expression of CD39 and/or CD197 was observed. HD-CAR-1 demonstrated encouraging efficacy and exceptionally low treatment-specific toxicity, presenting new treatment options for patients with r/r CLL. Trial registration: #NCT03676504.

CT-219 Clinical Evaluation of Fast-in-Time (FIT) Anti-CD19 CAR T—a Non-Viral, 2-Day Rapid Manufacture CAR T-Cell Therapy for B-Cell Malignancies

CT-219 Clinical Evaluation of Fast-in-Time (FIT) Anti-CD19 CAR T—a Non-Viral, 2-Day Rapid Manufacture CAR T-Cell Therapy for B-Cell Malignancies

Safety and Efficacy of 9 Days Vein-to-Vein Decentralized Manufactured Anti-CD19 CAR T-Cell Therapy for Relapsed/Refractory B-cell Leukemia and Lymphoma: Results from the First Phase 1 Indian Trial (VELCART)

Safety and Efficacy of 9 Days Vein-to-Vein Decentralized Manufactured Anti-CD19 CAR T-Cell Therapy for Relapsed/Refractory B-cell Leukemia and Lymphoma: Results from the First Phase 1 Indian Trial (VELCART)

CT-165 Safety and Efficacy of 9 Days Veinto-Vein Decentralized Manufactured Anti-CD19 CAR T-Cell Therapy for Relapsed/Refractory B-cell Leukemia and Lymphoma: Results from the First Phase 1 Indian Trial (VELCART)

CT-165 Safety and Efficacy of 9 Days Veinto-Vein Decentralized Manufactured Anti-CD19 CAR T-Cell Therapy for Relapsed/Refractory B-cell Leukemia and Lymphoma: Results from the First Phase 1 Indian Trial (VELCART)

Understanding the role of B cells in CAR T-cell therapy in leukemia through a mathematical model.

Chimeric antigen receptor T (CAR T) cell therapy has been proven to be successful against a variety of leukemias and lymphomas. This paper undertakes an analytical and numerical study of a mathematical model describing the competition of CAR T, leukemia, tumor, and B cells. Considering its significance in sustaining anti-CD19 CAR T-cell stimulation, a B-cell source term is integrated into the model. Through stability and bifurcation analyses, the potential for tumor eradication, contingent on the continuous influx of B cells, has been revealed, showing a transcritical bifurcation at a critical B-cell input. Additionally, an almost heteroclinic cycle between equilibrium points is identified, providing a theoretical basis for understanding disease relapse. Analyzing the oscillatory behavior of the system, the time-dependent dynamics of CAR T cells and leukemic cells can be approximated, shedding light on the impact of initial tumor burden on therapeutic outcomes. In conclusion, the study provides insights into CAR T-cell therapy dynamics for acute lymphoblastic leukemias, offering a theoretical foundation for clinical observations and suggesting avenues for future immunotherapy modeling research.

Pharmacologic inhibition of dipeptidyl peptidase 1 (cathepsin C) does not block in vitro granzyme-mediated target cell killing by CD8 T or NK cells.

Recently developed small-molecule inhibitors of the lysosomal protease dipeptidyl peptidase 1 (DPP1), also known as cathepsin C (CatC), can suppress suppurative inflammation in vivo by blocking the processing of zymogenic (pro-) forms of neutrophil serine proteases (NSPs), including neutrophil elastase, proteinase 3, and cathepsin G. DPP1 also plays an important role in activating granzyme serine proteases that are expressed by cytotoxic T lymphocytes (CTL) and natural killer (NK) cells. Therefore, it is critical to determine whether DPP1 inhibition can also cause off-target suppression of CTL/NK-cell-mediated killing of virus-infected or malignant cells. Herein, we demonstrate that the processing of human granzymes A and B, transitioning from zymogen to active proteases, is not solely dependent on DPP1. Thus, the killing of target cells by primary human CD8+ T cells, NK cells, and gene-engineered anti-CD19 CAR T cells was not blocked in vitro even after prior exposure to high concentrations of the reversible DPP1 inhibitor brensocatib. Consistent with this observation, the turnover of model granzyme A/B peptide substrates in the human CTL/NK cell lysates was not significantly reduced by brensocatib. In contrast, preincubation with brensocatib almost entirely abolished (>90%) both the cytotoxic activity of mouse CD8+ T cells and granzyme substrate turnover. Overall, our finding that the effects of DPP1 inhibition on human cytotoxic lymphocytes are attenuated in comparison to those of mice indicates that granzyme processing/activation pathways differ between mice and humans. Moreover, the in vitro data suggest that human subjects treated with reversible DPP1 inhibitors, such as brensocatib, are unlikely to experience any appreciable deficits in CTL/NK-cell-mediated immunities.

A Multicenter Real-life Prospective Study of Axicabtagene Ciloleucel versus Tisagenlecleucel Toxicity and Outcomes in Large B-cell Lymphomas.

This real-world prospective observational study across 21 Italian centers (CART-SIE) compares axicabtagene ciloleucel (axi-cel) and tisagenlecleucel (tisa-cel) outcomes in 485 patients with relapsed/refractory large B-cell lymphoma with baseline characteristics matched by stabilized inverse propensity score weighting. Axi-cel versus tisa-cel had higher all-grade cytokine release syndrome (78.6% vs. 89.3%, P = 0.0017) and neurotoxicity (9.9% vs. 32.2%, P < 0.0001) but also superior progression-free survival (PFS) at 1 year (46.5% vs. 34.1%, P = 0.0009). Even among patients who failed bridging therapy, axi-cel PFS was superior to tisa-cel (37.5% vs. 22.7%, P = 0.0059). Differences in overall survival and high-grade immune toxicities were not significant. The CAR-HEMATOTOX score not only predicted hematologic toxicity but also 1-year survival outcomes (51.5% in CAR-HEMATOTOX high vs. 77.2% in CAR-HEMATOTOX low, P < 0.0001). Twenty patients developed second primary malignancies, including two cases of T-cell neoplasms. These findings enable more informed selection of anti-CD19 CAR T-cell therapy, balancing bridging, safety, and efficacy considerations for individual patients. Significance: The findings of this study on 485 patients with relapsed/refractory large B-cell lymphoma treated with commercial axi-cel and tisa-cel indicate axi-cel's superior PFS after propensity score weighting. The predictive utility of CAR-HEMATOTOX in assessing not only toxicity but also outcomes across both CAR T-cell products may guide future risk-stratified management strategies.

Molecular Disease Monitoring in Patients With Relapsed/refractory B-Cell Lymphoma Receiving Anti-CD19 CAR T-Cell Therapy

BackgroundChimeric antigen receptor (CAR) T-cell therapy has improved the historically poor outcomes for relapsed and refractory (R/R) large B-cell non-Hodgkin's lymphoma (LBCL). However, nearly 60% of patients will either fail to respond or relapse after CAR T-cell therapy. Currently, PET/CT scans are used to assess response. Cell-free circulating tumor DNA (ctDNA) is released by tumor cells into the peripheral blood and can be measured for minimal residual disease (MRD) assessment. MethodsIn this retrospective, IRB approved pilot study, archived lymphoma tissue and ctDNA from peripheral blood samples on day 0, 14, 28, 56, 90, 180, and 365 after CAR T-cell infusion from 10 patients with R/R NHL were collected for next-generation sequencing (NGS) of clonal variable-diversity-joining (VDJ) rearrangements (Adaptive biotechnologies [Seattle, WA]). Response was assessed by PET/CT on days 90 and 365 and graded according to the Lugano 2014 criteria. The primary endpoint was to determine the feasibility of detecting ctDNA to monitor disease response after anti-CD19 CAR T-cell therapy. The secondary endpoint was to compare the sensitivity/specificity of MRD assessment from ctDNA to PET/CT imaging. ResultsNine out of 10 patients with a trackable sequence [median age 69 (range: 56-76); 55.6% male; median LDH 224], were included in this study. Each received tisagenlecleucel (tisa-cel) CAR T-cell therapy after median 2 prior treatments (range: 2-4). 7/9 patients had R/R diffuse large B-cell lymphoma (DLBCL), and 2/9 had transformed follicular lymphoma. At a median follow up of 12.7 months (range: 1.5-30 months), 4 patients were alive. By day 90, 3 patients (33.3%) achieved a radiographic complete response (CR) whilst 6 patients (66.6%) had progressive disease (PD). Detectable MRD on day 14 or day 28 had 83% sensitivity and 100% specificity for radiographic progression at any time before 1 year. For patients with PD, the median (interquartile range) MRD at day 0, 14, and 28 were 17.31 (1.01, 96.84), 9.12 (0.30, 18.8), and 23.77 (8.01, 137.53) copies per milliliter (mL), respectively. For patients with detectable MRD at day 28, mOS and mPFS were 6.7 and 1.3 months, respectively. ConclusionMonitoring MRD was a sensitive and specific method to detect poor response to tisa-cel. Additional studies evaluating MRD more frequently and with different products are warranted.

Anti-CD19 chimeric antigen receptor T-cell therapy has less efficacy in Richter transformation than in de novo large B-cell lymphoma and transformed low-grade B-cell lymphoma.

The activity of anti-CD19 CAR T cell therapy in chronic lymphocytic leukemia (CLL) with Richter's transformation (RT) to aggressive large B cell lymphoma (LBCL) is largely unknown. In a multicenter retrospective study, we report the safety and efficacy of CAR T cell therapy in patients with RT (n=30) compared to patients with aggressive B cell lymphoma (n=283) and patients with transformed indolent Non-Hodgkins Lymphoma (iNHL) (n=141) between April 2016 and January 2023. Two-thirds of patients received prior therapy for CLL before RT and 89% of them received B-cell receptor and B-cell lymphoma 2 (BCL-2) inhibitors. Toxicities of CAR T cell therapy in RT were similar to other lymphomas, with no fatalities related to cytokine release syndrome or immune effector-cell associated neurotoxicity synderome. The 100-day overall response rate and complete response rates in patients with RT were 57% and 47%, respectively. With a median follow up of 19 months, the median overall survival (OS) was 9.9 months in patients with RT compared to 18 months in de-novo LBCL and not reached in patients with transformed iNHL. The OS at 12 months was 45% in patients with RT compared with 62% and 75% in patients with de novo LBCL and transformed iNHL, respectively. In a multivariate analysis, worse OS was associated with RT histology, elevated LDH, and more prior lines of therapy. CAR T cell therapy can salvage a proportion of patients with CLL and RT exposed to prior targeted agents; however, efficacy in RT is inferior compared to de novo LBCL and transformed iNHL.

In vivo CAR T-cell generation in nonhuman primates using lentiviral vectors displaying a multidomain fusion ligand

AbstractChimeric antigen receptor (CAR) T-cell therapies have demonstrated transformative efficacy in treating B-cell malignancies. However, high costs and manufacturing complexities hinder their widespread use. To overcome these hurdles, we have developed the VivoVec platform, a lentiviral vector capable of generating CAR T cells in vivo. Here, we describe the incorporation of T-cell activation and costimulatory signals onto the surface of VivoVec particles (VVPs) in the form of a multidomain fusion protein and show enhanced in vivo transduction and improved CAR T-cell antitumor functionality. Furthermore, in the absence of lymphodepleting chemotherapy, administration of VVPs into nonhuman primates resulted in the robust generation of anti-CD20 CAR T cells and the complete depletion of B cells for >10 weeks. These data validate the VivoVec platform in a translationally relevant model and support its transition into human clinical testing, offering a paradigm shift in the field of CAR T-cell therapies.

Late events after anti-CD19 CAR T-cell therapy for relapsed/refractory B-cell non-Hodgkin lymphoma.

The short-term complications from chimeric antigen receptor T-cell therapy (CART) are well characterized, but the long-term complications still need to be further investigated. Therefore, herein, we will review the currently available literature published on the late adverse events following CART. We reviewed published data available from pivotal trials and real-world experiences with anti-CD19 CART (CART19) for adults with lymphoma. We defined late events as occurring or persisting beyond 1 month after CART infusion. We focused our literature review on the following late-event outcomes post-CART19: cytopenia, immune reconstitution, infections, and subsequent malignancies. Grade 3-4 cytopenia beyond 30 days occurs in 30%-40% of patients and beyond 90 days in 3%-22% of patients and is usually managed with growth-factor and transfusion support, along with neutropenic prophylaxis. B-cell aplasia and hypogammaglobulinemia are expected on-target off-tumor effects of CART19, 44%-53% of patients have IgG < 400 mg/dL, and approximately 27%-38% of patients receive intravenous immunoglobulin (IVIG) replacement. Infections beyond the initial month from CART19 are not frequent and rarely severe, but they are more prevalent and severe when patients receive subsequent therapies post-CART19 for their underlying disease. Late neurotoxicity and neurocognitive impairment are uncommon, and other causes should be considered. T-cell lymphoma (TCL) after CART is an extremely rare event and not necessarily related to CAR transgene. Myeloid neoplasm is not rare post-CART, but unclear causality given heavily pretreated patient population is already at risk for therapy-related myeloid neoplasm. CART19 is associated with clinically significant long-term effects such as prolonged cytopenia, hypogammaglobulinemia, and infections that warrant clinical surveillance, but they are mostly manageable with a low risk of non-relapse mortality. The risk of subsequent malignancies post-CART19 seems low, and the relationship with CART19 and/or prior therapies is unclear; but regardless of the possible causality, this should not impact the current benefit-risk ratio of CART19 for relapsed/refractory B-cell non-Hodgkin lymphoma (NHL).

Safety and efficacy of armored huCART19-IL18 in patients with relapsed/refractory lymphomas that progressed after anti-CD19 CAR T cells.

7004 Background: A substantial proportion of patients (pts) with relapsed/refractory (R/R) non-Hodgkin lymphomas (NHL) will not derive a long-term benefit from the existing anti-CD19 chimeric antigen receptor (CAR) T cells. To enhance therapeutic efficacy, we have engineered huCART19-IL18, a 4th generation 4-1BB anti-CD19 construct, armored with the ability to secrete the pro-inflammatory cytokine, IL-18. Methods: This is a first-in-human trial using huCART19-IL18 for CD19+ B-cell malignancies (NCT04684563). Expedited 3-day manufacturing is utilized to limit T-cell exhaustion. To be eligible for the NHL cohort, pts must be R/R to prior anti-CD19 CAR T cells if indicated by FDA label. Dose levels (DL) between 3x106 and 3x108 of huCART19-IL18+ cells are administered as a single IV infusion following lymphodepleting chemotherapy. Bridging therapy is optional. Responses are first assessed at 3 months (mo) using Lugano criteria. Results: As of January 20, 2024, 21 pts with CD19+ NHL were infused with huCART19-IL18. Characteristics include median age 64 yrs (47-74), 76% male, 9 (43%) DLBCL, 6 (29%) FL, 3 (14%) MCL, 2 (10%) tFL, 1 (5%) HGBCL. Median number of prior Rx was 7 (4-14) with 20 (95%) pts R/R to prior anti-CD19 CAR T cells. Manufacturing of DL5 (3x108) was not feasible due to inability to achieve the target dose in 4/6 (67%) pts assigned to DL5. 18 (86%) pts received bridging. 3 pts received DL1 (3x106), 4 pts DL2 (7x106), 1 pt non-defined dose (2.8x107), 6 pts DL3 (3x107), 5 pts DL4 (7x107), 2 pts DL5 (3x108). No study-related deaths occurred in 21 safety-evaluable pts. CRS occurred in 15 (71%) pts: G1 in 8 (38%), G2 in 4 (19%), G3 in 3 (14%). ICANS occurred in 3 (14%) pts: G1 in 2 (10%), G2 in 1 (5%). The most common G3 adverse events at least possibly related to huCART19-IL18 included fatigue (38%), hypotension (29%), and low fibrinogen (23%). 20 pts are efficacy evaluable with median (m) follow-up of 15 mo (3-31). The 3 mo ORR was 80% (90% CI: 60-93%), with CR 50% (90% CI: 30-70%) and PR 30% (90% CI: 14-51%). mDOR was 10 mo (5.5-NR). mPFS was 8.7 mo (90% CI 5-NR), and mOS was NR (90% CI 25 mo-NR). We detected continued persistence of huCART19-IL18 in pts with 24 mo follow-up. No correlation between cell dose and outcome was identified, but response rates and mean expansion (copies/µg gDNA) were higher in pts previously exposed to CD28 CAR than those who had prior 4-1BB CAR (Table). Conclusions: Treatment with huCART19-IL18 has an acceptable safety profile and produced durable remissions in heavily pre-treated pts with R/R NHL despite prior CAR T-cell therapy. The subtype of the preceding CAR product may influence the expansion and effectiveness of huCART19-IL18. Clinical trial information: NCT04684563 . [Table: see text]

Estimating the health care costs associated with receipt of lisocabtagene maraleucel: Insights from adults with mantle cell lymphoma (TRANSCEND NHL 001).

7028 Background: Anti-CD19 CAR T cell therapy is a major advancement for treating R/R B-cell malignancies such as mantle cell lymphoma (MCL). While effective disease management with CAR T cell therapy is expected to reduce patients’ health care resource utilization (HCRU) over the long-term, few studies have examined the short-term impacts of this treatment on HCRU and associated health care costs. Here, we used data from the TRANSCEND NHL 001 (NCT02631044) clinical trial to estimate the HCRU-related costs incurred by patients with R/R MCL over the first 12 months after receipt of lisocabtagene maraleucel (liso-cel). Methods: A retrospective analysis of clinical trial data was conducted to calculate the frequency of HCRU (medications [excluding liso-cel], diagnostics, procedures, ICU and non-ICU hospitalizations) observed over the 12 months immediately after administration of liso-cel. Costs for each HCRU event were derived from public databases and literature, adjusted to 2023 United States (US) dollars, and used to estimate patient-level health care costs. Results: Of the patients treated (N = 88), 76.1% were male, 87.5% were White, and mean ± standard deviation (SD) age was 67.5 ± 9 years. All patients were treated in the US and completed a median (range) of 3 (1–11) prior lines of therapy before receiving liso-cel. Most patients (93.2%) received the recommended dose of 100 × 106 CAR+ T cells. The total mean ± SD per-patient cost (excluding liso-cel) was estimated at $138,413 ± $58,555 over 12 months. Facility use accounted for 77.7% of all costs, primarily owing to non-ICU hospitalizations (98.9%), which had a mean ± SD length of stay of 19.5 ± 16.7 days per eligible patient. Half of all health care costs were incurred within the first month of infusion (53.2%), with each subsequent month contributing a fraction (1.5%–6.3%) of total costs. A total of 13 out of 88 patients received their initial infusion in an outpatient setting and incurred 23% fewer costs compared with those who received their infusion in an inpatient setting ($110,050 vs $143,418), primarily as a function of reduced first-month facility use. Total costs for patients receiving liso-cel in outpatient settings were further reduced to $72,771 upon exclusion of 3 outliers. Conclusions: Non-ICU hospitalizations were the largest driver of liso-cel–related costs in this R/R MCL cohort of clinical trial participants. Most of the cost burden was incurred within 1 month of treatment, with dramatic reductions in HCRU and health care costs observed thereafter. Results suggest that treatment in the outpatient setting, even in part (eg, at initial infusion only), may confer substantial cost savings to the health care system.

A study of a new mechanism: Intracellular retention allo-CART safety and efficacy for extranodal bulky B-NHL.

e19007 Background: Extranodal bulky lesions, a significant adverse prognostic factor in lymphoma, commonly denote a more aggressive disease course, mandating prompt and intensified treatment strategies. In response, we developed ThisCART19A, a non-genetic editing and off-the-shelf anti-CD19 CAR T-cell therapy incorporating intracellular retention of membrane proteins, representing a novel approach that downregulates surface expression of TCRαβ/CD3 complexes. ThisCART19 has exhibited a favorable safety profile and promising efficacy in patients with relapsed/refractory bulky B-cell Non-Hodgkin Lymphoma. Methods: This is an investigator-initiated trial employing an open-label, dose escalation, and expansion design to evaluate the safety and efficacy of ThisCART19A in patients with relapsed or refractory bulky B-cell non-Hodgkin lymphoma (B-NHL). Bulky disease was defined as the longest diameter of the mass &gt;5 cm at baseline. Results: Between June, 2021, and June, 2023, 13 extranodal bulky disease were enrolled in the studies and successfully received ThisCART19A. The median age was 56 (range, 37~67) years. All 13 patients had 3 median prior lines of therapy (range, 2-5). All patients received anti-CD20 and multi- agent chemotherapy. 8 (61.54%) patients had prior auto CART. mSPD was 48 (range, 16~162) cm². mTMTV was 114.9 (range, 14~483) ml. As of February 2024, The most common adverse events were CRS (100%) , infections (30.77%), ICANS (23.08%) and cytopenias(100%); This is no grade 3 or higher CRS occurred;only 1(7.69%)patient experienced grade 4 ICANS and relieved after intravenous dexamethasone treatment. This is no treatment-related deaths occurred. Among the 13 patients, 10 were evaluable, with an ORR and CR of 90% and 80%, respectively, at 28 days post-infusion. mPFS was 62 days (range, 28~227). The patient who achieved a PR received chemotherapy and radiotherapy as consolidation, As of February 5th, 2024, the patient has survived for 263 days and is still under follow-up. Additionally, two patients progressed after CR received sequential chemotherapy and BCL-2 Inhibitor, with an average OS of 326.5 days, still being under follow-up. In 13 evaluable patients, the mean C-max was 1043.13 cells/μL(range, 0.59~10045.4), and the mean AUC0-28d was 1542.23 cells/μL × day(range, 0.91~11724).In this cohort, two patients received low-dose infusions at 1×106 cells/kg and still achieved excellent expansion, the respective C-max were 726.432 cells/μL and 336.67 cells/μL. Conclusions: This CART19A exhibited favorable safety, remarkable expansion potential, and efficacy profiles in the treatment of r/r bulky lymphoma. Notably, it achieved a high ORR of 90%, providing a favorable window of opportunity for subsequent consolidation and intensification treatments. Moreover, this transition from a bulky to a non-bulky disease state reduces the intricacy of follow-up treatments. Clinical trial information: NCT04384393 .

Generating universal anti-CD19 CAR T cells with a defined memory phenotype by CRISPR/Cas9 editing and safety evaluation of the transcriptome.

Chimeric antigen receptor-expressing T cells (CAR T cells) have revolutionized cancer treatment, particularly in B cell malignancies. However, the use of autologous T cells for CAR T therapy presents several limitations, including high costs, variable efficacy, and adverse effects linked to cell phenotype. To overcome these challenges, we developed a strategy to generate universal and safe anti-CD19 CAR T cells with a defined memory phenotype. Our approach utilizes CRISPR/Cas9 technology to target and eliminate the B2M and TRAC genes, reducing graft-versus-host and host-versus-graft responses. Additionally, we selected less differentiated T cells to improve the stability and persistence of the universal CAR T cells. The safety of this method was assessed using our CRISPRroots transcriptome analysis pipeline, which ensures successful gene knockout and the absence of unintended off-target effects on gene expression or transcriptome sequence. In vitro experiments demonstrated the successful generation of functional universal CAR T cells. These cells exhibited potent lytic activity against tumor cells and a reduced cytokine secretion profile. The CRISPRroots analysis confirmed effective gene knockout and no unintended off-target effects, validating it as a pioneering tool for on/off-target and transcriptome analysis in genome editing experiments. Our findings establish a robust pipeline for manufacturing safe, universal CAR T cells with a favorable memory phenotype. This approach has the potential to address the current limitations of autologous CAR T cell therapy, offering a more stable and persistent treatment option with reduced adverse effects. The use of CRISPRroots enhances the reliability and safety of gene editing in the development of CAR T cell therapies. We have developed a potent and reliable method for producing universal CAR T cells with a defined memory phenotype, demonstrating both efficacy and safety in vitro. This innovative approach could significantly improve the therapeutic landscape for patients with B cell malignancies.

Outcomes of patients aged ≥26 years with relapsed or refractory B-cell acute lymphoblastic leukemia in ZUMA-3 and historical trials

Brexucabtagene autoleucel (brexu-cel) is an autologous anti-CD19 CAR T-cell therapy approved in the USA and European Union (EU) for adults with relapsed or refractory B-cell acute lymphoblastic leukemia (R/R B-ALL; aged ≥26 years in EU). Here, outcomes for patients with R/R B-ALL aged ≥26 years in ZUMA-3 treated with brexu-cel were compared with historical standard-of-care (SOC) therapy. After median follow-up of 26.8 months, the overall complete remission (CR) rate among patients treated with brexu-cel in Phase 2 (N = 43) was 72% and median overall survival (OS) was 25.4 months (95% CI, 15.9-NE). Median OS was improved in Phase 2 patients versus matched historical SOC-treated patients. Compared with aggregate historical trial data, Phase 1 and 2 patients had improved OS versus blinatumomab, inotuzumab, and chemotherapy in a matching-adjusted indirect comparison (MAIC) study. These data demonstrate clinical benefit of brexu-cel relative to SOC in patients ≥26 years with R/R B-ALL.

CAR T cells outperform CAR NK cells in CAR-mediated effector functions in head-to-head comparison

BackgroundCAR NK cells as vehicles for engineered “off-the-shelf” cellular cancer immunotherapy have attracted significant interest. Nonetheless, a comprehensive comparative assessment of the anticancer activity of CAR T cells and CAR NK cells carrying approved benchmark anti-CD19 CAR constructs is missing. Here, we report a direct head-to-head comparison of CD19-directed human T and NK cells.MethodsWe generated CAR T and CAR NK cells derived from healthy donor PBMC by retroviral transduction with the same benchmark second-generation anti-CD19 CAR construct, FMC63.28z. We investigated IFN-γ secretion and direct cytotoxicity in vitro against various CD19+ cancer cell lines as well as in autologous versus allogeneic settings. Furthermore, we have assessed anticancer activity of CAR T and CAR NK cells in vivo using a xenograft lymphoma model in an autologous versus allogeneic setting and a leukemia model.ResultsOur main findings are a drastically reduced capacity for CAR-mediated IFN-γ production and lower CAR-mediated cytotoxicity of CAR NK cells relative to CAR T cells in vitro. Consistent with these in vitro findings, we report superior anticancer activity of autologous CAR T cells compared with allogeneic CAR NK cells in vivo.ConclusionsCAR T cells had significantly higher CAR-mediated effector functions than CAR NK cells in vitro against several cancer cell lines and autologous CAR T cells outperformed allogeneic CAR NK cells both in vitro and in vivo. CAR NK cells will likely benefit from further engineering to enhance anticancer activity to ultimately fulfill the promise of an effective off-the-shelf product.