Autologous Chimeric Antigen Receptor Research Articles

Prognostic impact of corticosteroid and tocilizumab use following chimeric antigen receptor T-cell therapy for multiple myeloma.

Despite being the mainstay of management for cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS), there is limited data regarding the impact of tocilizumab (TCZ) and corticosteroids (CCS) on chimeric antigen receptor (CAR) T-cell efficacy in multiple myeloma (MM). The present study aims to evaluate the prognostic impact of these immunosuppressants in recipients of BCMA- or GPRC5D-directed CAR T cells for relapsed/refractory MM. Our retrospective cohort involved patients treated with commercial or investigational autologous CAR T-cell products at a single institution from March 2017-March 2023. The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall response rate (ORR), complete response rate (CRR), and overall survival (OS). In total, 101 patients (91% treated with anti-BCMA CAR T cells and 9% treated with anti-GPRC5D CAR T cells) were analyzed. Within 30 days post-infusion, 34% received CCS and 49% received TCZ for CRS/ICANS management. At a median follow-up of 27.4 months, no significant difference in PFS was observed between CCS and non-CCS groups (log-rank p = 0.35) or between TCZ and non-TCZ groups (log-rank p = 0.69). ORR, CRR, and OS were also comparable between evaluated groups. In our multivariable model, administering CCS with/without TCZ for CRS/ICANS management did not independently influence PFS (HR, 0.74; 95% CI, 0.36-1.51). These findings suggest that, among patients with relapsed/refractory MM, the timely and appropriate use of CCS or TCZ for mitigating immune-mediated toxicities does not appear to impact the antitumor activity and long-term outcomes of CAR T-cell therapy.

BCMA/CD47-directed universal CAR-T cells exhibit excellent antitumor activity in multiple myeloma

BackgroundBCMA-directed autologous chimeric antigen receptor T (CAR-T) cells have shown excellent clinical efficacy in relapsed or refractory multiple myeloma (RRMM), however, the current preparation process for autologous CAR-T cells is complicated and costly. Moreover, the upregulation of CD47 expression has been observed in multiple myeloma, and anti-CD47 antibodies have shown remarkable results in clinical trials. Therefore, we focus on the development of BCMA/CD47-directed universal CAR-T (UCAR-T) cells to improve these limitations.MethodsIn this study, we employed phage display technology to screen nanobodies against BCMA and CD47 protein, and determined the characterization of nanobodies. Furthermore, we simultaneously disrupted the endogenous TRAC and B2M genes of T cells using CRISPR/Cas9 system to generate TCR and HLA double knock-out T cells, and developed BCMA/CD47-directed UCAR-T cells and detected the antitumor activity in vitro and in vivo.ResultsWe obtained fourteen and one specific nanobodies against BCMA and CD47 protein from the immunized VHH library, respectively. BCMA/CD47-directed UCAR-T cells exhibited superior CAR expression (89.13-98.03%), and effectively killing primary human MM cells and MM cell lines. BCMA/CD47-directed UCAR-T cells demonstrated excellent antitumor activity against MM and prolonged the survival of tumor-engrafted NCG mice in vivo.ConclusionsThis work demonstrated that BCMA/CD47-directed UCAR-T cells exhibited potent antitumor activity against MM in vitro and in vivo, which provides a potential strategy for the development of a novel “off-the-shelf” cellular immunotherapies for the treatment of multiple myeloma.Graphic

Generation of allogeneic CAR-NKT cells from hematopoietic stem and progenitor cells using a clinically guided culture method.

Cancer immunotherapy with autologous chimeric antigen receptor (CAR) T cells faces challenges in manufacturing and patient selection that could be avoided by using 'off-the-shelf' products, such as allogeneic CAR natural killer T (AlloCAR-NKT) cells. Previously, we reported a system for differentiating human hematopoietic stem and progenitor cells into AlloCAR-NKT cells, but the use of three-dimensional culture and xenogeneic feeders precluded its clinical application. Here we describe a clinically guided method to differentiate and expand IL-15-enhanced AlloCAR-NKT cells with high yield and purity. We generated AlloCAR-NKT cells targeting seven cancers and, in a multiple myeloma model, demonstrated their antitumor efficacy, expansion and persistence. The cells also selectively depleted immunosuppressive cells in the tumor microenviroment and antagonized tumor immune evasion via triple targeting of CAR, TCR and NK receptors. They exhibited a stable hypoimmunogenic phenotype associated with epigenetic and signaling regulation and did not induce detectable graft versus host disease or cytokine release syndrome. These properties of AlloCAR-NKT cells support their potential for clinical translation.

Challenges and Lessons Learned in Autologous Chimeric Antigen Receptor T-Cell Therapy Development from a Statistical Perspective.

Chimeric antigen receptor (CAR) T-cell therapy is a human gene therapy product where T cells from a patient are genetically modified to enable them to recognize desired target antigen(s) more effectively. In recent years, promising antitumor activity has been seen with autologous CAR T cells. Since 2017, six CAR T-cell therapies for the treatment of hematological malignancies have been approved by the Food and Drug Administration (FDA). Despite the rapid progress of CAR T-cell therapies, considerable statistical challenges still exist for this category of products across all phases of clinical development that need to be addressed. These include (but not limited to) dose finding strategy, implementation of the estimand framework, use of real-world data in contextualizing single-arm CAR T trials, analysis of safety data and long-term follow-up studies. This paper is the first step in summarizing and addressing these statistical hurdles based on the development of the six approved CAR T-cell products.

Advancing Autologous CAR T-cell Therapy through Real-Time Patient Health Data Integration: A Simulation-Based Approach

Autologous chimeric antigen receptor (CAR) T-cell therapy presents promising treatment outcomes for various cancers. However, its potential is restrained by unique supply chain challenges, including dynamic patient health conditions and extended turnaround time. These challenges often lead to missed optimal treatment windows, impeding the effective delivery of life-saving treatments. This paper presents SimPAC (Simulation-based decision support for Patient-centric manufacturing of Autologous Cell therapies). SimPAC is designed to model and incorporate real-time patient health conditions into the supply chain decisions of autologous CAR T-cell therapy. SimPAC integrates system dynamics and agent-based simulation techniques, facilitating the adaptation of manufacturing processes and production schedules based on real-time patient health conditions. SimPAC can model various patient disease progressions using parametric functions, non-parametric functions, or tabular data. Additionally, SimPAC offers easy configuration options to model various cell therapy supply chains. We provide two case studies to demonstrate the capabilities of SimPAC and highlight the benefits of patient-centric manufacturing, including improved survival rates and potential economic advantages. However, while the benefits are significant, our study also emphasizes the importance of balancing improved patient outcomes, economic viability, and ethical considerations in the context of personalized medicine. SimPAC can be used to explore applications of this approach to diverse therapeutic contexts and supply chain configurations.

Stealth transgenes enable CAR-T cells to evade host immune responses

BackgroundAdoptive cell therapy, such as chimeric antigen receptor (CAR)-T cell therapy, has improved patient outcomes for hematological malignancies. Currently, four of the six FDA-approved CAR-T cell products use the FMC63-based...

Engineering immune-evasive allogeneic cellular immunotherapies.

Allogeneic cellular immunotherapies hold a great promise for cancer treatment owing to their potential cost-effectiveness, scalability and on-demand availability. However, immune rejection of adoptively transferred allogeneic T and natural killer (NK) cells is a substantial obstacle to achieving clinical responses that are comparable to responses obtained with current autologous chimeric antigen receptor T cell therapies. In this Perspective, we discuss strategies to confer cell-intrinsic, immune-evasive properties to allogeneic T cellsand NK cells in order to prevent or delay their immune rejection, thereby widening the therapeutic window. We discuss how common viral and cancer immune escape mechanisms can serve as a blueprint for improving the persistence of off-the-shelf allogeneic cell therapies. The prospects of harnessing genome editing and synthetic biology to design cell-based precision immunotherapies extend beyond programming target specificities and require careful consideration of innate and adaptive responses in the recipient that may curtail the biodistribution, in vivo expansion and persistence of cellular therapeutics.

Sequencing of Therapy Matters in the Era of Autologous Chimeric Antigen Receptor T-cell Therapy

Sequencing of Therapy Matters in the Era of Autologous Chimeric Antigen Receptor T-cell Therapy

Abstract P66: Off-The-Shelf Epstein Barr Virus Specific T Cells Armored with B7-H3-Targeting Chimeric Antigen Receptors Is an Effective and Safe Tumor- Agnostic Therapy For B7-H3 Positive Solid Malignancies

Abstract In contrast to its limited expression in normal tissues, the B7 homolog 3 protein (B7-H3) is over-expressed in many human tumors, making it an attractive target for chimeric antigen receptor (CAR) T cell therapy. To address the technical challenges limiting broader patient access to autologous CAR T cell therapy, we armoured Epstein-Barr Virus Specific T Cells (EBVSTs) with CARs as an off-the-shelf therapy against solid tumors. We identified and utilised a nanobody as the domain specifically targeting B7-H3 in our CAR construct to reduce the stability issues associated with scFv-based domains. Our B7H3.CAR armored EBVSTs demonstrated potent in-vitro and in-vivo activity against multiple B7-H3 positive tumor and patient-derived xenografts models. Analysis of human healthy tissues and tumors microarrays indicated that B7-H3 expression, while elevated in patient tumors, was differentially low in healthy tissues. Consistent with this, mouse T cells expressing a murine equivalent of our B7H3.CAR displayed good on-target off-tumor safety in immunocompetent mice bearing syngeneic tumors. Further in-vitro evaluation revealed that while human T, B and NK cells were unaffected by B7H3.CAR EBVSTs targeting, monocytes were readily targeted due to the upregulation of B7-H3. Consequent to this targeting and depletion of B7-H3 positive human myeloid cells which are key mediators of CRS, a low incidence of cytokine release syndrome was observed in humanized mice after B7H3.CAR EBVST treatment. Lastly, we showed that B7H3.CAR EBVSTs can target myeloid-derived suppressor cells (MDSCs) that express B7-H3 and in doing so, alleviate MDSC-driven immune suppression. Our findings demonstrate that our nanobody-based B7H3.CAR EBVSTs present not only an effective and safe off-the-shelf approach for targeting any B7-H3-positive solid tumor while also addressing challenges that hindered the clinical development of CAR T cells in such indications. Citation Format: Siok Ping Yeo, Lindsay Kua, Jin Wei Tan, Joanna Kristyn Lim, Fiona Wong, May Delos Santos, Chek Meng Poh, Angeline Goh XH, Xin Yu Koh, Xiao Hua Zhou, Rajarethinam R, Qing Feng Chen, Zhisheng Her, Ivan D Horak, Lionel Low, Kar Wai Tan. Off-The-Shelf Epstein Barr Virus Specific T Cells Armored with B7-H3-Targeting Chimeric Antigen Receptors Is an Effective and Safe Tumor- Agnostic Therapy For B7-H3 Positive Solid Malignancies [abstract]. In: Proceedings of Frontiers in Cancer Science; 2023 Nov 6-8; Singapore. Philadelphia (PA): AACR; Cancer Res 2024;84(8_Suppl):Abstract nr P66.

Human anti-PSCA CAR macrophages possess potent antitumor activity against pancreatic cancer.

Due to the limitations of autologous chimeric antigen receptor (CAR)-T cells, alternative sources of cellular immunotherapy, including CAR macrophages, are emerging for solid tumors. Human induced pluripotent stem cells (iPSCs) offer an unlimited source for immune cell generation. Here, we develop human iPSC-derived CAR macrophages targeting prostate stem cell antigen (PSCA) (CAR-iMacs), which express membrane-bound interleukin (IL)-15 and truncated epidermal growth factor receptor(EGFR) for immune cell activation and a suicide switch, respectively. These allogeneic CAR-iMacs exhibit strong antitumor activity against human pancreatic solid tumors invitro and invivo, leading to reduced tumor burden and improved survival in a pancreatic cancer mouse model. CAR-iMacs appear safe and do not exhibit signs of cytokine release syndrome or other invivo toxicities. We optimized the cryopreservation of CAR-iMac progenitors that remain functional upon thawing, providing an off-the-shelf, allogeneic cell product that can be developed into CAR-iMacs. Overall, our preclinical data strongly support the potential clinical translation of this human iPSC-derived platform for solid tumors, including pancreatic cancer.

Abstract 5254: The “off-the-shelf ”CD19-CAR-Vδ1T cells demonstrated an enhanced therapeutic effect on B-cell malignancy models

Abstract Background: The commercialization of autologous chimeric antigen receptor T cell (CAR-T) is hindered by the expensive and time-consuming manufacturing process, presenting major challenges. The development of allogeneic products is proposed as an alternative strategy to overcome these obstacles. Vδ1T cells, possessing active homing capability, are known to infiltrate tumor tissues and have been linked with favorable patient prognosis due to their direct killing effect via innate immunity and their sensitive T cell receptors that can broadly recognize tumor antigens. Unlike conventional αβ T cells, Vδ1 TCRs are not restricted by major histocompatibility complexes (MHCs), thus preventing the development of graft-versus-host disease (GVHD). Therefore, Vδ1T cells were hypothesized to be a superior candidate for universal CAR-T cells. Nevertheless, the small portion of Vδ1T cells (less than 1%) in peripheral blood posts a significant challenge for CMC and production. Here we present the successful development of CD19-CAR-Vδ1T cells, which demonstrate enhanced therapeutic efficacy on B-cell malignancy models. Methods: High-purity CD19-CAR-Vδ1T cells were prepared using PersonGen's proprietary platform technology. Multiple CAR structures were tested for cytotoxicity, and the fourth-generation CAR-transduced Vδ1 cells designated as UTAA09 exhibited sustained killing of CD19+ target cells. UTAA09 underwent in-depth research regarding its anti-tumor efficacy and safety. Results: The Vδ1T cell purity exceeded 95%, while the residual TCRαβ count remained under 1%. The CAR transduction efficiency remained stable across batches, with medium CAR+~30%, and up to 2×1011 UTAA09 cells were harvested in compliance with GMP standards. The presence of secreted IL-2 significantly increased the persistence of UTAA09 in vitro, and UTAA09 showed comparable anti-tumor activity and expansion rates to CD19-CAR-αβT cells. Notably, no exhaustion phenotype was detected for UTAA09 after multiple antigen stimulation processes. Moreover, UTAA09 lacked detectable IL-17A, indicating a non-promoting characteristic in tumor growth. In the xenograft model, significant inhibition of tumor growth was observed in all mice, of which 40% achieved long-term disease-free survival (p<0.01) . On days 5, 12, and 19 after the administration of UTAA09, Vδ1T cells underwent significant expansion in all 5 mice tested. Subsequent analysis confirmed that the majority of these expanded Vδ1T cells were CAR+ cells, indicating the specific and long-lasting expansion of CD19-CAR+ Vδ1T cells in vivo. Importantly, none of the mice experienced significant weight loss, demonstrating the safety and outstanding in vivo effectiveness of UTAA09. Conclusion: UTAA09 shows potential as an off-the-shelf allogeneic cellular therapy for the treatment of B-cell malignancies and autoimmune diseases derived from B cells. Citation Format: Dan Chen, Fengtao You, Cheng Chen, Shufen Xiang, Ping Zhang, Hai Wu, Zhong Zheng, Min Wang, Xingbing Wang, Huimin Meng, Nan Yang, Bozhen Zhang, Lin Yang. The “off-the-shelf ”CD19-CAR-Vδ1T cells demonstrated an enhanced therapeutic effect on B-cell malignancy models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5254.

Abstract 39: Preclinical in vitro and in vivo evaluation of CD8αβ+ CD19 CAR iPSCs T cells generated in a TCR signal-independent manner using DLL4/VCAM-coupled microbeads

Abstract The use of clonally-derived, induced pluripotent stem cells (iPSCs) as starting material for therapeutic T cell manufacturing would overcome many limitations of autologous Chimeric Antigen Receptor T cell (CAR-T) therapies. Complex, multi-stage genome engineering, large batch production and rigorous lot testing could provide a consistent source of off-the-shelf, functionally enhanced T cell products. However, this vision cannot be realized using existing T cell differentiation platforms, which fail to present Notch ligands with the precision and intensity required to control T cell differentiation in scalable, suspension culture. We have previously shown that VCAM1 synergizes with DLL4 to enhance Notch signaling and progenitor T cell differentiation. We have extended the utility of this discovery through the creation of DLL4/VCAM1-coated magnetic microbeads, enabling precise and temporal control of Notch signaling in suspension culture. iPSC-derived CD34+ cells cultured with DLL4/VCAM1 beads demonstrate dose-responsive activation of Notch gene expression (e.g., Notch1, DTX1, TCF7), resultant T lineage commitment (e.g. CD5, CD7 expression) and maturation to CD4-CD8+ (single positive) cells in a TCR signal-independent manner. Removal of the endogenous TCR is necessary to prevent graft-versus-host-disease. Therefore, differentiation and maturation in a TCR-independent process presents substantial advantage in the development of safe, off the shelf iPSC T cell products. Using a clonal iPSC line with a CD19 CAR knocked in at the TRAC locus, we apply this approach to generate CAR-expressing, CD8αβ+ functional T cells, capable of multiple rounds of in vitro tumor cell lysis and sustained tumor growth inhibition in vivo comparable to primary T cells. This advancement demonstrates proof-of-concept for generation of highly efficacious, off-the-shelf CAR-T cells using novel, small-footprint manufacturing in order to broaden the applicability and accessibility of T cell therapies for cancer patients. Citation Format: Muluken S. Belew, Richard Carpenedo, Alessia Pallaoro, Hiofan Hoi, Avisek Deyati, Daniel C. Kirouac, Siddarth Chandrasekaran, Valerie Wall, Libin Abraham, Sommer Apelu, Michael H. Cadell, Amanda AuYeung, Omar Subedar, Elisa Martinez, Shri Joshi, Elizabeth Csaszar, Steven Woodside, Emily Titus, Christopher Bond. Preclinical in vitro and in vivo evaluation of CD8αβ+ CD19 CAR iPSCs T cells generated in a TCR signal-independent manner using DLL4/VCAM-coupled microbeads [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 39.

Clinical Pharmacology Considerations for the "Off-the-Shelf" Allogeneic Cell Therapies.

Autologous chimeric antigen receptor T-cell (CAR-T) therapies have garnered unprecedented clinical success with multiple regulatory approvals for the treatment of various hematological malignancies. However, there are still several clinical challenges that limit their broad utilization for aggressive disease conditions. To address some of these challenges, allogeneic cell therapies are evaluated as an alternative approach. As compared with autologous products, they offer several advantages, such as a more standardized "off the shelf" product, reduced manufacturing complexity, and no requirement of bridging therapy. As with autologous CAR-T therapies, allogeneic cell therapies also present clinical pharmacology challenges due to their invivo living nature, unique pharmacokinetics or cellular kinetics (CKs), and complex dose-exposure-response relationships that are impacted by various patient- and product-related factors. On top of that, allogeneic cell therapies present additional unique challenges, including attenuated invivo persistence and graft-vs.-host disease risk as compared with autologous counterparts. This review draws comparison between autologous and allogeneic cell therapies, summarizing key engineering aspects unique to allogeneic cell therapy. Clinical pharmacology learnings from emerging clinical data of allogeneic cell therapy programs are also highlighted, with particular emphasis on CK, dose-exposure-response relationship, lymphodepletion regimen, repeat dosing, and patient- and product-related factors that can impact CK and patient outcomes. There are specific unique challenges and opportunities arising from the development of allogeneic cell therapies, especially in optimizing lymphodepletion and establishing a regimen for repeat dosing. This review highlights how clinical pharmacologists are well positioned to help address these challenges by leveraging novel clinical pharmacology and modeling and simulation approaches.

Cryopreserved leukapheresis material can be transferred from controlled rate freezers to ultracold storage at warmer temperatures without affecting downstream CAR-T cell culture performance and in-vitro functionality

Chimeric antigen receptor (CAR) T-cell therapies are increasingly adopted as a commercially available treatment for hematologic and solid tumor cancers. As CAR-T therapies reach more patients globally, the cryopreservation and banking of patients’ leukapheresis materials is becoming imperative to accommodate intra/inter-national shipping logistical delays and provide greater manufacturing flexibility. This study aims to determine the optimal temperature range for transferring cryopreserved leukapheresis materials from two distinct types of controlled rate freezing systems, Liquid Nitrogen (LN2)-based and LN2-free Conduction Cooling-based, to the ultracold LN2 storage freezer (≤−135 °C), and its impact on CAR T-cell production and functionality. Presented findings demonstrate that there is no significant influence on CAR T-cell expansion, differentiation, or downstream in-vitro function when employing a transfer temperature range spanning from −30 °C to −80 °C for the LN2-based controlled rate freezers as well as for conduction cooling controlled rate freezers. Notably, CAR T-cells generated from cryopreserved leukapheresis materials using the conduction cooling controlled rate freezer exhibited suboptimal performance in certain donors at transfer temperatures lower than −60 °C, possibly due to the reduced cooling rate of lower than 1 °C/min and extended dwelling time needed to reach the final temperatures within these systems. This cohort of data suggests that there is a low risk to transfer cryopreserved leukapheresis materials at higher temperatures (between −30 °C and −60 °C) with good functional recovery using either controlled cooling system, and the cryopreserved materials are suitable to use as the starting material for autologous CAR T-cell therapies.

Genome editing approaches for universal chimeric antigen receptor T cells

Autologous chimeric antigen receptor (CAR) T cell therapy has revolutionised the management of certain B-cell malignancies. However, as bespoke therapies, challenges include complex manufacturing logistics and risks ranging from suboptimal harvests to inadvertent transduction and masking of blast populations. Premanufactured, ready -to -use allogeneic CAR T cells could mitigate some of these hurdles if barriers created by HLA (Human leukocyte antigen) mismatching can be addressed. Genome editing to disrupt TCRαβ (T-cell receptor αβ) expression has been shown to be effective in addressing alloreactivity and avoiding graft versus host disease (GVHD). Platforms including transcription activator-like effector nucleases (TALENs), homing endonucleases and clustered regularly interspersed short palindromic repeats (CRISPR) / Cas9 have allowed multiplex editing of TCR genes in combination with CD52, the target antigen of alemtuzumab, as a strategy to evade lymphodepletion used to prevent host v graft rejection effects. Alternative approaches have targeted pathways to prevent HLA expression on donor T cells, and have also allowed targeted insertion of CAR genes, including placing transgene expression under the control of endogenous transcriptional machinery. These tools have rapidly progressed to clinical trials, and applications have extended beyond B-cell malignancies, showing promising early results in other settings, including relapsed/refractory(r/r) T-cell leukaemia. Short term immunological effects and toxicities have been generally manageable, and long-term monitoring is ongoing to help build confidence in safety over time.

High-Specificity CRISPR-Mediated Genome Engineering in Anti-BCMA Allogeneic CAR T Cells Suppresses Allograft Rejection in Preclinical Models.

Allogeneic chimeric antigen receptor (CAR) T cell therapies hold the potential to overcome many of the challenges associated with patient-derived (autologous) CAR T cells. Key considerations in the development of allogeneic CAR T cell therapies include prevention of graft-vs-host disease (GvHD) and suppression of allograft rejection. Here, we describe preclinical data supporting the ongoing first-in-human clinical study, the CaMMouflage trial (NCT05722418), evaluating CB-011 in patients with relapsed/refractory multiple myeloma. CB-011 is a hypoimmunogenic, allogeneic anti-B-cell maturation antigen (BCMA) CAR T cell therapy candidate. CB-011 cells feature 4 genomic alterations and were engineered from healthy donor-derived T cells using a Cas12a CRISPR hybrid RNA-DNA (chRDNA) genome-editing technology platform. To address allograft rejection, CAR T cells were engineered to prevent endogenous HLA class I complex expression and overexpress a single-chain polyprotein complex composed of beta-2 microglobulin (B2M) tethered to HLA-E. In addition, T-cell receptor (TCR) expression was disrupted at the TCR alpha constant locus in combination with the site-specific insertion of a humanized BCMA-specific CAR. CB-011 cells exhibited robust plasmablast cytotoxicity in vitro in a mixed lymphocyte reaction in cell cocultures derived from patients with multiple myeloma. In addition, CB-011 cells demonstrated suppressed recognition by and cytotoxicity from HLA-mismatched T cells. CB-011 cells were protected from natural killer cell-mediated cytotoxicity in vitro and in vivo due to endogenous promoter-driven expression of B2M-HLA-E. Potent antitumor efficacy, when combined with an immune-cloaking armoring strategy to dampen allograft rejection, offers optimized therapeutic potential in multiple myeloma. See related Spotlight by Caimi and Melenhorst, p. 385.

Optimisation of a primary human CAR-NK cell manufacturing pipeline.

Autologous chimeric antigen receptor (CAR) T-cell therapy of B-cell malignancies achieves long-term disease remission in a high fraction of patients and has triggered intense research into translating this successful approach into additional cancer types. However, the complex logistics involved in autologous CAR-T manufacturing, the compromised fitness of patient-derived Tcells, the high rates of serious toxicities and the overall cost involved with product manufacturing and hospitalisation have driven innovation to overcome such hurdles. One alternative approach is the use of allogeneic natural killer (NK) cells as a source for CAR-NK cell therapy. However, this source has traditionally faced numerous manufacturing challenges. To address this, we have developed an optimised expansion and transduction protocol for primary human NK cells primed for manufacturing scaling and clinical evaluation. We have performed an in-depth comparison of primary human NK cell sources as a starting material by characterising their phenotype, functionality, expansion potential and transduction efficiency at crucial timepoints of our CAR-NK manufacturing pipeline. We identified adult peripheral blood-derived NK cells to be the superior source for generating a CAR-NK cell product because of a higher maximum yield of CAR-expressing NK cells combined with potent natural, as well as CAR-mediated anti-tumor effector functions. Our optimised manufacturing pipeline dramatically improves lentiviral transduction efficiency of primary human NK cells. We conclude that the exponential expansion pre- and post-transduction and high on-target cytotoxicity make peripheral blood-derived NK cells a feasible and attractive CAR-NK cell product for clinical utility.

Allogeneic CAR T Cell Therapy for Cancer

Autologous chimeric antigen receptor (CAR) T cell therapy, produced from the patient's own T cells, has changed the treatment landscape for hematologic malignancies but has some drawbacks that prevent large-scale clinical application, including logistical complexities in supply, patient T cell health, treatment delays, and limited manufacturing slots. Allogeneic, or off-the-shelf, CAR T cell therapies have the potential to overcome many of the limitations of autologous therapies, with the aim of bringing benefit to all patients eligible for treatment. This review highlights the progress and challenges of allogeneic cell therapies for cancer and the various approaches that are being evaluated preclinically and in clinical trials to enhance the persistence and antitumor efficacy of allogeneic CAR T cells, including new strategies to avoid immune rejection. Expected final online publication date for the Annual Review of Cancer Biology, Volume 8 is April 2024. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

FDA Investigating CAR-Related T-cell Malignancies.

The FDA is investigating reports that BCMA- and CD19-directed autologous chimeric antigen receptor T-cell immunotherapies, which are used to treat a variety of blood cancers, may be causing secondary malignancies. However, the agency and hematologists say the potential benefits of the agents, which have saved thousands of lives, outweigh this risk.

Bridging treatment prior to chimeric antigen receptor T-cell therapy in multiple myeloma.

Autologous patient-derived adoptive T-cell therapies have revolutionized the management of relapsed multiple myeloma (MM). However, the current manufacturing and quality control processes result in lengthy vein-to-vein time, making bridging therapy necessary for most patients. Yet the decision and choice of optimal bridging therapy are complex in the heavily pretreated relapsed MM patient. In this perspective piece, the authors provide their approach and considerations while selecting an optimal bridging regimen before autologous chimeric antigen receptor T-cell therapy.