Allogeneic Cell Therapy Research Articles

A first-in-human phase 1, multicenter, open-label study of CB-012, a next-generation CRISPR-edited allogeneic anti-CLL-1 CAR-T cell therapy for adults with relapsed/refractory acute myeloid leukemia (AMpLify).

TPS6586 Background: CAR-T cell therapies have shown significant clinical benefit in treating adults with many hematologic malignancies. In acute myeloid leukemia (AML), a challenge in the development of CAR-T cell therapies has been the limitation of suitable target antigens since many are also expressed on hematopoietic stem cells (HSCs). The target antigen C-type lectin-like molecule-1 (CLL-1) has emerged as an attractive therapeutic target due to its expression on AML mature blasts and leukemic stem cells and its absence on HSCs. CB-012 is an allogeneic CAR-T cell therapy that targets CLL-1. CB-012 is derived from healthy donor T cells by using Cas12a CRISPR hybrid RNA-DNA (chRDNA) technology to introduce 5 genome edits: (1) TRAC gene knockout (KO), which eliminates T cell receptor expression to reduce the risk of graft-versus-host disease, (2) site-directed insertion of a fully human anti-CLL-1 CAR into the TRAC locus, (3) KO of PD-1 to enhance antitumor activity by reducing T cell exhaustion, (4) β2-microgobulin ( B 2M) gene KO, which eliminates HLA class I presentation to mitigate host T cell-mediated rejection, and (5) site-directed insertion of a B2M–HLA-E-peptide fusion into the B 2M locus to reduce NK cell-mediated rejection. In murine xenograft models of AML, CB-012 significantly reduced the tumor burden and increased the survival of mice bearing CLL-1+PD-L1+ tumors. Methods: CB-012 is being evaluated in a multicenter, Phase 1 clinical trial in patients with relapsed/refractory (r/r) AML. A 3+3 dose escalation design is being utilized with the primary objectives to determine the safety and tolerability of CB-012 and the recommended Phase 2 dose (RP2D). An expansion phase will follow dose escalation at the recommended dose(s) for expansion. Additional objectives include preliminary antitumor activity and pharmacokinetics. Key inclusion criteria include nonproliferative disease defined as ≤25% blasts in the bone marrow and peripheral blood, ECOG performance status ≤1, and adequate organ function. After receiving lymphodepletion therapy with cyclophosphamide (750 mg/m2/d) and fludarabine (30 mg/m2/d) administered concurrently for 3 days followed by a 2-day break, patients receive a single-dose infusion of CB-012 and are followed for safety and efficacy. The dose escalation portion of the study is actively enrolling patients. The AMpLify trial is registered at clinicaltrials.gov (NCT06128044). Clinical trial information: NCT06128044 .

The interim analysis of a first-in-human phase 1 trial of ET-901, a CRISPR edited allogeneic immune-cloaked anti-CD19 CAR-T cell therapy in patients with r/r B-NHL.

e19010 Background: Allogeneic CAR T-cell therapy faces challenges like limited persistence and host rejection. Current research has improved its viability by modifying genes like B2M, despite new challenges like NK cell targeting have emerged. Through CRISPR screening, we discovered a novel gene, named GeneX, and its role in enhancing T cell persistence against allogeneic attacks and AICD. GeneX influences glycan composition, affecting immune responses and AICD initiation. Engineered GeneXKO/TCRKO/anti-CD19 CAR T cells (ET-901) resisted allogeneic killing and maintained anti-tumor effects without causing GvHD, marking a significant advancement in CAR T-cell therapy. Methods: ET-901 is being tested in a phase 1 trial for r/r B-NHL at a single center, utilizing a 3+3 dose escalation scheme and planning for expansion at the recommended Phase 2 dose. Participants must have an ECOG status of 0–2, without a history of allo-HSCT or CAR-T therapy. The study's main goals are to assess ET-901's safety and establish the optimal Phase 2 dosage. Patients undergo a 3-day lymphodepletion with fludarabine (30-50 mg/m2/d) and cyclophosphamide (500-1000 mg/m2/d), followed by a single-dose infusion of ET-901 at escalating doses (DL1:1*10e6/kg, DL2:3*10e6/kg, and DL3:10*10e6/kg). Pharmacokinetic monitoring occurs during follow-up. Results: From September 2023, a total of six patients were enrolled in the escalation cohort, including 4 patients with LBCL and 2 with FL. In these patients (3 males), the median age was 53 years (range: 46–55 years), and the median number of prior treatment lines was 5. The median SPD was 7,650 mm2 (range: 2,700-43,400 mm2). Notably, two cases in DL2 exhibited unusual lymphoma infiltration sites: patient No.4 in the forearm muscle and patient No.5 in the spleen. Update to February 2024, we have completed the safety evaluation of Dose Level (DL) 1 and DL2. No DLTs were observed. The most common TRAEs of any grade included leukopenia (6/6), granulocytopenia (6/6), anemia (6/6), thrombocytopenia (6/6), CRS (6/6), infection (2/6), ICANS (2/6), and GvH like reaction (1/6). All patients achieved objective responses, with 2 cases of PR and 4 cases of CR (1 in DL1, 3 in DL2). The peak values of CAR+ cells count and VCN in peripheral blood were 36.0/μl (range: 14.0-48.0/μl, median: day 7), and 9.6e4 copies/μg (range: 7.7e4-1.2e5 copies/μg, median: day 7), respectively. In all patients, a second expansion of CAR-T cells was observed alongside B cell recovery. This confirms that GeneX knockout enables allo CAR-T cells to maintain long-term immune privilege while preserving their biological function. Conclusions: The study demonstrated the safety and feasibility of ET-901 in patients with r/r B-NHL. These findings highlight the potential of ET-901 as an effective therapeutic approach for improving outcomes for these patients. Clinical trial information: NCT06014073 .

The promising feeder-free allogenic NK cell therapy: Clinical outcomes of GIC-102 monotherapy (GIC-102101) and synergistic potential with GI-101 (CD80-IgG4 Fc-IL2v) in advanced solid tumors and hematologic malignancies.

e14526 Background: The allogeneic Natural Killer (NK) cell therapy derived from healthy donors may overcome the short lifespan and dysfunctional anti-tumor activity of current autologous approach. This limitation often restricts treatment efficacy and necessitating high dosages and frequent infusions. GIC-102, non-engineered / feeder-free, highly potent allogeneic NK cell derived from healthy donors, is a promising alternative. Here, we present the clinical outcomes from the Phase 1 study of GIC-102, along with nonclinical evidence demonstrating outstanding pharmacokinetics (PK) and pharmacodynamics (PD) when used in combination with a novel bi-specific Fc fusion protein, GI-101 (CD80-IgG4 Fc-IL2v/NCT04977453/KEYNOTE-B59). Methods: GIC-102101, a first-in-human study, evaluated GIC-102 monotherapy at doses of 1x109 QW and 3x109 QW in patients with advanced solid tumors or hematologic malignancies. A lympho-conditioning strategy using cyclophosphamide (300 mg/m2) and fludarabine (30 mg/m2) was implemented every two cycles before GIC-102 treatment. The study employed a conventional 3+3 dose escalation scheme. The primary endpoint was to determine the safety and tolerability of GIC-102, with tumor response assessed as secondary endpoints. Additionally, the PK/PD profile of GIC-102 in combination with GI-101 was evaluated in a mouse model. Results: As of December 31, 2023, six patients have been treated with GIC-102 monotherapy including two patients with Non-Hodgkin lymphoma (NHL), and four patients with metastatic colorectal cancer (CRC). The median number of prior treatments for patients with CRC and NHL was 4 and 6, respectively. No dose limiting toxicities (DLTs) were observed and maximum tolerated dose was not reached. Treatment-related adverse events (TRAEs) occurred in 5 patients (83%), with the majority being associated with the lympho-conditioning procedure; hyponatremia, neutropenia, lymphopenia and anemia. The best overall response was complete response (CR) in 1/6 patient (NHL) and stable disease (SD) in 4/6 patients (3 CRC, 1 NHL). Treatment for 1 CR (NHL) and 2 SD (CRC) is ongoing (for NHL, 215+ days/for CRC, 160+ days and 153+ days). The in-vivo study of GIC-102 in combination with GI-101 showed significantly enhanced anti-tumor activity and in-vivo NK cell proliferation lasting up to 4 weeks. Conclusions: The GIC-102, feeder-free allogeneic NK cell, was well tolerated without DLTs and demonstrated early promise in efficacy in patients for advanced solid tumors and hematologic malignancy. Further clinical investigation of GIC-102 in combination with GI-101, bi-specific Fc fusion protein, is currently ongoing. Clinical trial information: NCT05880043 .

Effect of placental circulating T cells expressing CD16 on multiple hematological and solid tumor cancers through combination with various monoclonal antibodies.

2554 Background: PT-CD16VS is an allogeneic cell therapy derived from human postpartum placental circulating T (PT) cells that are genetically modified to express CD16 and endogenous T cell receptor (TCR) knockout. PT-CD16VS cells can be combined with various monoclonal antibodies to engage in anti-tumor antibody-dependent cellular cytotoxicity (ADCC) against diverse cancers with a “universal receptor” approach. Here we report the characterization and preclinical evaluation of PT-CD16VS in combination with monoclonal antibodies against both hematological and solid tumor cancers. Methods: PT cells were activated, transduced with a lentiviral vector containing a construct expressing a high affinity CD16 variant, CD16VS, and transfected to knock out the TCR. In vitro,functional activity of PT-CD16VS cells in combination with monoclonal antibodies was assessed in cytotoxicity, cytokine release, and proliferation assays. Invivo, PT-CD16VS was combined with Rituximab in a Raji xenograft model in NSG mice, and with Trastuzumab in a subcutaneous NCI-N87 xenograft model in NSG mice in which tumor volume was measured and tumor samples were evaluated for PT-CD16VS infiltration. Results: In vitro, PT-CD16VS exhibited potent ADCC and cytokine release when combined with Rituximab against CD20+ Burkitt's lymphoma (Daudi and Raji), with Trastuzumab against HER2+ gastric carcinoma (NCI-N87), with Trastuzumab or Avelumab against HER2+/PDL-1+ non-small cell lung carcinoma (NCI-H1975) and Trastuzumab-resistant metastatic mammary adenocarcinoma (JIMT-1), and with Cetuximab against EGFR+ triple negative metastatic mammary adenocarcinoma (MDA-MB-231). Moreover, examples of PT-CD16VS antigen-specific proliferation were demonstrated against Raji and NCI-N87 when cells were combined with Rituximab and Trastuzumab, respectively. In vivo, in combination with Rituximab in the Raji mouse model, PT-CD16VS exhibited significant survival benefit compared to vehicle and Rituximab alone treated groups. In the subcutaneous NCI-N87 solid tumor model, PT-CD16VS with Trastuzumab demonstrated significant reduction in tumor volume compared to vehicle, Trastuzumab, and Enhertu groups. In addition, PT-CD16VS infiltration into the tumor was shown to be Trastuzumab dependent, with infiltrating cells expressing high levels of CD16 and Ki67. Conclusions: Our results show that PT-CD16VS have potent in vitro and in vivo ADCC activity, and a single drug product has the potential to be combined with various monoclonal antibodies to target multiple cancers across hematological and solid tumor indications. This “universal receptor” with antibody-dependent targeting approach, together with the benefits of an allogeneic cell platform, may democratize accessibility of such therapies for patients.

Payload-delivering engineered γδ T cells display enhanced cytotoxicity, persistence, and efficacy in preclinical models of osteosarcoma.

T cell-based cancer immunotherapy has typically relied on membrane-bound cytotoxicity enhancers such as chimeric antigen receptors expressed in autologous αβ T cells. These approaches are limited by tonic signaling of synthetic constructs and costs associated with manufacturing. γδ T cells are an emerging alternative for cellular therapy, having innate antitumor activity, potent antibody-dependent cellular cytotoxicity, and minimal alloreactivity. We present an immunotherapeutic platform technology built around the innate properties of the Vγ9Vδ2 T cell, harnessing specific characteristics of this cell type and offering an allocompatible cellular therapy that recruits bystander immunity. We engineered γδ T cells to secrete synthetic tumor-targeting opsonins in the form of an scFv-Fc fusion protein and a mitogenic IL-15Rα-IL-15 fusion protein (stIL15). Using GD2 as a model antigen, we show that GD2-specific opsonin-secreting Vγ9Vδ2 T cells (stIL15-OPS-γδ T cells) have enhanced cytotoxicity and promote bystander activity of other lymphoid and myeloid cells. Secretion of stIL-15 abrogated the need for exogenous cytokine supplementation and further mediated activation of bystander natural killer cells. Compared with unmodified γδ T cells, stIL15-OPS-γδ T cells exhibited superior in vivo control of subcutaneous tumors and persistence in the blood. Moreover, stIL15-OPS-γδ T cells were efficacious against patient-derived osteosarcomas in animal models and in vitro, where efficacy could be boosted with the addition of zoledronic acid. Together, the data identify stIL15-OPS-γδ T cells as a candidate allogeneic cell therapy platform combining direct cytolysis with bystander activation to promote tumor control.

Objective response after immune checkpoint inhibitors in a chemotherapy-refractory pMMR/MSS metastatic rectal cancer patient primed with experimental AlloStim® immunotherapy

BackgroundImmune Checkpoint Inhibitor (ICI) immunotherapy is most effective in immune effector cell infiltrated ‘hot’ tumor lesions, such as occurs in deficient mismatch repair, microsatellite instability high (dMMR/MSI-H) colorectal cancer (CRC). However, most all metastatic CRC tumors are mismatch repair proficient/microsatellite stable (pMMR/MSS) ‘cold’ lesions, without significant immune cell infiltration, and are unresponsive to ICI. AlloStim®, is an experimental, allogeneic immunomodulatory cell therapy designed to convert ‘cold’ metastatic tumor lesions to ‘hot’ inflamed lesions. After AlloStim® immunotherapy, this cold to hot inflammatory mechanism can make it difficult to distinguish between pseudoprogression and actual progression on restaging CT scans, as inflamed metastatic lesions can appear larger and occult disease can appear as new small lesions.MethodsTo explore whether radiological progression after AlloStim® immunotherapy is due to immune-flare or disease progression, we administered a short course of a combination ICI therapy to a pMMR/MSS chemotherapy-refractory metastatic colorectal cancer patient enrolled in the StimVax Phase IIb clinical study that presented with radiological progression after AlloStim® immunotherapy. Our rationale was that an accelerated response to ICI should occur if the lesions were inflamed, while if the enlarged lesions were due to disease progression there would not be a response.ResultsHere we report a rapid, significant reduction in tumor burden in response to ICI administration in an AlloStim® primed pMMR/MSS mCRC patient with retroperitoneal and lung metastases.ConclusionThis rare objective response to ICIs in a pMMR/MSS mCRC patient supports further evaluation of the combination of AlloStim® with ICI immunotherapy in MSS mCRC and other cold or ICI refractory tumors.Trial registrationNational Library of Medicine (NLM) at the National Institutes of Health (NIH). Registered 22 June 2020, https://clinicaltrials.gov/study/NCT04444622.

Potent and specific killing of SLE donor B Cells with AlloNK (AB-101), an allogeneic cord blood-derived NK cell therapy, in combination with anti-CD19 or anti-CD20 monoclonal antibodies

Abstract B cells play a crucial role in the pathogenesis of SLE by producing autoantibodies that target self-antigens, leading to tissue damage and inflammation. Here we demonstrate proof of concept for the use of a NK cell therapy to enhance the depletion of SLE donor B cells in the presence of anti-CD19 or anti-CD20 antibodies by an antibody dependent cellular cytotoxicity (ADCC) mechanism. AlloNK™ is a non-engineered, allogeneic, off-the-shelf, cryopreserved NK cell product, currently being evaluated in a clinical trial in combination with rituximab in subjects with lupus nephritis. AlloNK, which has been optimized for ADCC, was tested in combination with anti-CD20 (rituximab, obinutuzumab) or anti-CD19 (tafasitamab) mAbs in a short-term ADCC assay to show specific killing of SLE donor B cells. PBMC were isolated from SLE donors and co-cultured with AlloNK at various effector to target (E:T) ratios and mAbs concentrations. After 4h, the percentage of caspase 3/7+ B and T cells was determined by flow cytometry. At a 1:1 E:T ratio, AlloNK mediated killing of B cells in the presence of obinutuzumab (range 79-95%), rituximab (range 19-62%), and tafasitamab (range 24-77%) in a dose-dependent manner. Killing was specific as no off-target apoptosis of T cells was observed. Taken together, these data suggest that AlloNK has the potential to be effective in combination with mAbs to induce deeper B cell depletion and improved efficacy, over the mAbs alone, in SLE.

Development of KoRV-pseudotyped lentiviral vectors for efficient gene transfer into freshly isolated immune cells

Allogeneic cell therapies, such as those involving macrophages or Natural Killer (NK) cells, are of increasing interest for cancer immunotherapy. However, the current techniques for genetically modifying these cell types using lenti- or gamma-retroviral vectors present challenges, such as required cell pre-activation and inefficiency in transduction, which hinder the assessment of preclinical efficacy and clinical translation. In our study, we describe a novel lentiviral pseudotype based on the Koala Retrovirus (KoRV) envelope protein, which we identified based on homology to existing pseudotypes used in cell therapy. Unlike other pseudotyped viral vectors, this KoRV-based envelope demonstrates remarkable efficiency in transducing freshly isolated primary human NK cells directly from blood, as well as freshly obtained monocytes, which were differentiated to M1 macrophages as well as B cells from multiple donors, achieving up to 80% reporter gene expression within three days post-transduction. Importantly, KoRV-based transduction does not compromise the expression of crucial immune cell receptors, nor does it impair immune cell functionality, including NK cell viability, proliferation, cytotoxicity as well as phagocytosis of differentiated macrophages. Preserving immune cell functionality is pivotal for the success of cell-based therapeutics in treating various malignancies. By achieving high transduction rates of freshly isolated immune cells before expansion, our approach enables a streamlined and cost-effective automated production of off-the-shelf cell therapeutics, requiring fewer viral particles and less manufacturing steps. This breakthrough holds the potential to significantly reduce the time and resources required for producing e.g. NK cell therapeutics, expediting their availability to patients in need.

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.

Innovative therapies for treatment of invasive fungal diseases

Invasive fungal diseases (IFD) are difficult to treat and pose a significant threat to immunocompromised individuals. Current antifungal agents face limitations, including antifungal resistance and adverse effects. This review aims to give a comprehensive overview of emerging treatment strategies.Novel drugs in development are Ibrexafungerp, an orally available triterpenoid inhibiting glucan synthesis, and Rezafungin representing the echinocandins with extended half-life and improved tissue penetration, both recently licensed for certain indications. Fosmanogepix targets glycosylphosphatidylinositol biosynthesis, while Olorofim, an orotomide, inhibits fungal nucleic acid synthesis, both currently assessed in advanced clinical trials.Immunotherapeutic approaches include immune checkpoint inhibitors to enhance immune response in immunosuppressed individuals and fungal-specific allogeneic CAR-T cell therapy. For prophylactic purpose in high-risk populations to develop IFD, monoclonal antibodies against different virulence factors of Candida spp. have been discovered but are not yet seen in clinical trials. Vaccines against distinct fungal antigens as well as pan fungal vaccines to prevent IFD are under development in preclinical stages, notably for Candida spp., Cryptococcus spp., and Aspergillus spp., however, their clinical value is still discussed.In summary, major advances to treat IFD have been observed, but challenges for their establishment in the clinical routine persist.

Use of Darvadstrocel (Allogenic Stem Cell Therapy) for Crohn's Fistulas in Real Clinical Practice: The National Project to Implement Mesenchymal Stem Cell for the Treatment of Perianal Crohn's Fistula (the PRIME Study).

Perianal fistulas may affect 15% to 50% of patients with Crohn's disease. Treatment is complex, requiring a multidisciplinary approach. Darvadstrocel (allogenic mesenchymal cells obtained from lipoaspirates) was approved in 2018 by the European and Spanish Agencies of Medicines and Medical Products as a treatment for fistulas in Crohn's disease. Recent guidelines from the European Crohn's and Colitis Organisation and Spanish Working Group on Crohn's Disease and Ulcerative Colitis state that darvadstrocel is effective with a favorable safety profile and a strong level of evidence (n = 2). Presenting real-world effectiveness data for darvadstrocel in a Spanish population. Observational retrospective cohort study with prospective data gathering. The study was conducted at 14 institutions in Spain. From November 2019 to April 2022, all patients (n = 73) treated with darvadstrocel in these institutions were included, fulfilling the following criteria: 1) complex fistula/s in a patient with Crohn's disease; 2) failure of conventional and antitumor necrosis factor treatment; and 3) the absence of collections of >2 cm confirmed by pelvic MRI at the time of surgery. Darvadstrocel treatment. Clinical response (closure of 50% or more of external openings), complete clinical closure (100% of external openings), and radiological closure (no fluid collection >2 cm, edema, or inflammation) evaluated 6 months after treatment. Clinical response was observed in 63 patients (86.3%), complete clinical closure in 50 patients (68.5%), and radiological closure in 45 patients (69.2%). Combined clinical and radiological response was observed in 41 patients (63.1%). Not all clinically healed patients had radiological closure, and vice versa. No serious adverse events were reported. Retrospective nature of the study. Study results were consistent with those reported in previous clinical trials, real-world efficacy findings from the INSPIRE study (assessing darvadstrocel effectiveness in Europe, Israel, Switzerland, United Kingdom, and Japan), and previously published literature. Darvadstrocel was effective and demonstrated a favorable safety profile when used in normal clinical practice for the treatment of fistulas in Crohn's disease. See Video Abstract . ANTECEDENTES:Las fístulas perianales pueden afectar entre el 15 y el 50% de los pacientes con enfermedad de Crohn. El tratamiento es complejo y requiere un enfoque multidisciplinario. El darvadstrocel (células mesenquimales alogénicas obtenidas a partir de lipoaspirados) fue aprobado en 2018 por las Agencias Europea y Española de Medicamentos y Productos Sanitarios como tratamiento de las fístulas en la EC. Las recientes directrices de la Organización Europea de Crohn y Colitis y del Grupo de Trabajo Español sobre la Enfermedad de Crohn y Colitis Ulcerosa afirman que darvadstrocel es eficaz con un perfil de seguridad favorable y un sólido nivel de evidencia (2).OBJETIVO:Presentar datos de eficacia real de darvadstrocel en población española.DISEÑO:Estudio de cohorte retrospectivo observacional con recopilación prospectiva de datos.ESCENARIO:14 instituciones.PACIENTES:Desde noviembre de 2019 hasta abril de 2022, se incluyeron todos los pacientes (73) tratados con darvadstrocel en estas instituciones, que cumplieron los siguientes criterios: 1) fístula/s compleja/s en un paciente con enfermedad de Crohn; 2) fracaso del tratamiento convencional y anti factor de necrosis tumoral; 3) ausencia de colecciones > 2 cm confirmada por resonancia magnética pélvica en el momento de la cirugía.INTERVENCIONES:Tratamiento con Darvadstrocel.PRINCIPALES MEDIDAS DE RESULTADO:Respuesta clínica (cierre de ≥50% de las aberturas externas), cierre clínico completo (100% de las aberturas externas) y cierre radiológico (sin acumulación de líquido >2 cm, sin edema ni inflamación) evaluados 6 meses después del tratamiento.RESULTADOS:Se observó respuesta clínica en 63 pacientes (86.3%), cierre clínico completo en 50 pacientes (68.5%) y cierre radiológico en 45 pacientes (69.2%). Se observó respuesta clínica y radiológica combinada en 41 pacientes (63.1%). No todos los pacientes clínicamente curados tuvieron cierre radiológico y viceversa. No hubo eventos adversos graves reportados.LIMITACIONES:Estudio retrospectivoCONCLUSIONES:Los resultados del estudio fueron consistentes con los informados en ensayos clínicos anteriores, los hallazgos de eficacia en el mundo real del estudio INSPIRE (que evalúa la efectividad de darvadstrocel en Europa, Israel, Suiza, el Reino Unido y Japón) y la literatura publicada anteriormente. Darvadstrocel fue eficaz y demostró un perfil de seguridad favorable cuando se utiliza en la práctica clínica habitual para el tratamiento de fístulas en la enfermedad de Crohn. (Traducción-Dr. Jorge Silva Velazco ).

Innovations in bio-engineering and cell-based approaches to address immunological challenges in islet transplantation.

Human allogeneic pancreatic islet transplantation is a life-changing treatment for patients with severe Type 1 Diabetes (T1D) who suffer from hypoglycemia unawareness and high risk of severe hypoglycemia. However, intensive immunosuppression is required to prevent immune rejection of the graft, that may in turn lead to undesirable side effects such as toxicity to the islet cells, kidney toxicity, occurrence of opportunistic infections, and malignancies. The shortage of cadaveric human islet donors further limits islet transplantation as a treatment option for widespread adoption. Alternatively, porcine islets have been considered as another source of insulin-secreting cells for transplantation in T1D patients, though xeno-transplants raise concerns over the risk of endogenous retrovirus transmission and immunological incompatibility. As a result, technological advancements have been made to protect transplanted islets from immune rejection and inflammation, ideally in the absence of chronic immunosuppression, to improve the outcomes and accessibility of allogeneic islet cell replacement therapies. These include the use of microencapsulation or macroencapsulation devices designed to provide an immunoprotective environment using a cell-impermeable layer, preventing immune cell attack of the transplanted cells. Other up and coming advancements are based on the use of stem cells as the starting source material for generating islet cells 'on-demand'. These starting stem cell sources include human induced pluripotent stem cells (hiPSCs) that have been genetically engineered to avoid the host immune response, curated HLA-selected donor hiPSCs that can be matched with recipients within a given population, and multipotent stem cells with natural immune privilege properties. These strategies are developed to provide an immune-evasive cell resource for allogeneic cell therapy. This review will summarize the immunological challenges facing islet transplantation and highlight recent bio-engineering and cell-based approaches aimed at avoiding immune rejection, to improve the accessibility of islet cell therapy and enhance treatment outcomes. Better understanding of the different approaches and their limitations can guide future research endeavors towards developing more comprehensive and targeted strategies for creating a more tolerogenic microenvironment, and improve the effectiveness and sustainability of islet transplantation to benefit more patients.

Abstract CT180: Phase I clinical trial of CD19CAR -T cells secreting PD-1-targeting IL-21 in advanced relapsed/refractory acute lymphoblastic leukemia

Abstract Background/Purpose: Chimeric antigen receptor (CAR) T cell therapy has shown remarkable responses in hematologic malignancies. However, suboptimal clinical outcomes have been associated with decreased expansion and persistence of adoptive transferred CAR-T cells, antigen-negative relapses, and impairment by an immunosuppressive tumor microenvironment. We previously developed CD19CAR-T cells secreting PD-1Ab21 fusion protein composed of anti-PD-1 single chain antibody and IL-21(PD-1Ab21-CD19CAR-T). This investigator-initiated clinical trial is designed to assess the safety and efficacy of the novel CAR-T cells in advanced relapsed/refractory acute Lymphoblastic leukemia (ALL). Methods: This study recruited 10 patients with advanced relapsed/refractory B-ALL and half of them relapsed after allogeneic hematopoietic stem cell transplantation (allo-HSCT). All patients received fludarabine and cyclophosphamide before a single infusion of PD-1Ab21-CD19CAR-T cells at dose of 0.3, 1 or 3 x 106 cells/kg of body weight. The patients were monitored for adverse events, clinical response, as well as expansion of CAR-T and lymphocytes. Results: All five non-post-transplant patients achieved complete remission (CR), including two active CNS diseases, and three of them pursued consolidative allo-HSCT. Among the five post-transplant patients, one patient, who had undergone autologous, allogeneic CAR-T cell therapies and allo-HSCT, achieved CR and remained leukemia-free for 5 months, which was longer than the duration of remission (< 4 monthes) after allo-HSCT. The last treated patient achieved CR. Three other post-transplant patients, including two active CNS diseases, eventually died of the infection. One of the patients achieved minimal residual disease negative CR. The other two patients did not undergo laboratory evaluation, but their CNS symptoms disappeared. Once the expansion of CAR-T cells was detected, the proportion of CD8+T cell in CD3+T cells increased dramatically, rapidly reaching 77.8~91.2% and maintaining above 50% for a long time in all treated patients. Except for the three patients who died from infection, other patients experienced no or mild cytokine release syndrome (CRS) (grade ≤2). None of the patients had neurotoxic side effects. Conclusion: This study demonstrates that PD-1Ab21-secreting CAR-T cells are safe and effective therapeutic platform, even in cancer patients with CNS invasion. Our data also suggest that PD-1Ab21-secreting CAR-T therapy can activate endogenous anti-tumor CD8+ T cell responses. Citation Format: Yu Jing, Ying Li, Liping Dou, Shengjuan Zhang, Ran Tian, Guojing Wang, Xiangrui Cheng, Jitao Zhao, Hang Li, Yueyi An, Naibo Yang, Shengdian Wang. Phase I clinical trial of CD19CAR -T cells secreting PD-1-targeting IL-21 in advanced relapsed/refractory acute lymphoblastic leukemia [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT180.

Abstract LB341: Clinical validation and mechanistic insights of ThisCART: A novel allogeneic platform enhancing CAR-T signaling via intracellular TCRαβ/CD3 retention

Abstract Background: Current allogeneic CAR-T cell therapies face challenges with post-infusion expansion and efficacy. In response, we developed ThisCART, a non-genetic editing, allogeneic platform that significantly enhances CAR-T cell expansion and efficacy. This is achieved through a novel approach of intracellular retention of membrane proteins, reducing surface expression of TCRαβ/CD3 complexes and HLA-I molecules. Our lead product, ThisCART19, has demonstrated superior efficacy compared to conventional AutoCART19 in preclinical and early clinical studies for B-ALL. Methods: In the clinical trial NCT04384393, we assessed the safety and efficacy of ThisCART19 in patients with B-cell malignancies. Post-lymphodepletion, participants received infusions of ThisCART19 and AutoCART19, both personalized from the patient's own T cells, in equal proportions. Safety and efficacy were the primary endpoints, evaluated on Day 28 post-infusion and throughout extended follow-up. Mechanistic insights were gained through comprehensive multi-omics studies, including RNAseq, whole-cell proteomics, and phosphoproteomics. Results: ThisCART19 showed enhanced expansion and an improved safety profile in vivo. As of 01 January 2024, Two patients diagnosed as relapse/refractory acute B cell leukemia (R/R B-ALL) were enrolled in the clinical trial. Pt1 is a 55yo male with Ph-positive B-ALL (36% blasts) who relapsed after multiagent chemotherapy and TKIs. Pt2 is a 16yo male with CNS leukemia (78.5% blasts) after multiagent chemotherapy. No DLTs or ICANS were observed. Pt1 experienced Grade 1 CRS that resolved without treatment, and Pt2 experienced Grade 2 CRS that resolved after tocilizumab and corticosteroids. Complete remission with MRD-negative status was achieved by Day 28. Pharmacodynamic analysis indicated a significant expansion of CAR-T cells, predominantly in the CAR+TCR- subset, highlighting autonomous CAR signaling enhancement. Multi-omics analysis identified upregulation in JAK-STAT, PI3K-Akt, and NFKB pathways, suggesting improved cell proliferation, survival, anti-apoptotic activity, and effector function. This molecular profiling provides a mechanistic understanding of ThisCART19A's therapeutic efficacy. Conclusion: The ThisCART platform marks a transformative advancement in allogeneic CAR-T cell therapy. By enhancing CAR signaling autonomously through a unique intracellular retention of TCRαβ/CD3 complexes, ThisCART has shown promising safety and efficacy in early clinical trials. Its potential in reshaping the treatment landscape for hematological and autoimmune disorders positions ThisCART as a crucial development in cellular therapeutics. Citation Format: Jun Li, Lei Xue, Sujun Li, Ling He, Kaichun Liu, Rong Jin, Tao Wang, Yinhang Zhang, Shanshan Chen, Yulian Gao, Dan Liu, Liyun Yang, Xingbing Wang. Clinical validation and mechanistic insights of ThisCART: A novel allogeneic platform enhancing CAR-T signaling via intracellular TCRαβ/CD3 retention [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB341.

Abstract LB074: Preclinical development of API-192: An engineered CAR-NKT allogeneic cell therapy targeting CD19 and CD20 for the treatment of B-cell malignancies

Abstract Autologous chimeric antigen receptor (CAR)-T therapies have elicited high rates of durable complete responses in B cell lymphomas. Unfortunately, disease progression, manufacturing failures, and prohibitive costs highlight the need for an alternative source of cells that would provide a consistent and readily available therapy for patients. The “Appia Cells Utilized for Allogeneic” (ACUA) platform is an innovative process that differentiates cord blood-derived CD34+ hematopoietic stem and progenitor cells into large numbers of natural killer T (NKT) cells to support off-the-shelf treatment. NKT cells express an invariant T cell receptor (iTCR) and are naturally non-alloreactive, making them an ideal cell type for an allogeneic product. The ACUA platform circumvents the challenge of expanding NKT cells from the periphery where the cells comprise less than 1% of T cells. API-192 is an ACUA-derived, NKT cell product engineered to express dual CARs targeting CD19 and CD20 to prevent tumor antigen escape. At research scale, API-192 is a highly pure product (>90% iTCR+ 19CAR+ 20CAR+) that secretes soluble interleukin-15 for improved expansion and persistence. The transgenic iTCR is not expressed above physiologic levels and upon engagement, API-192 proliferates in response to and is cytotoxic against CD1d+ tumor cells in a ligand-dependent manner. In response to Raji and Nalm6 tumor cells, API-192 secretes pro-inflammatory cytokines, proliferates, and is cytotoxic in a dose- and CAR-dependent manner. API-192 can also control multiple rounds of tumor cell rechallenge in vitro. Using human tumor xenograft mouse models, we show that API-192 expands, controls tumor growth, and prolongs survival. Furthermore, API-192 persists in the periphery, enabling control of a tumor rechallenge at 70 days after initial dosing of effector cells. Indicative of a favorable immunogenic profile, API-192 expresses lower levels of MHC I and MHC II molecules relative to conventional CAR-T cells and elicits less interferon (IFN)-γ release by NK and T cells in a mixed lymphocyte reaction (MLR) assay. To address a theoretical concern that endogenous TCRαβ rearrangement could occur during the ACUA process, we performed genomic DNA based TCR sequencing to quantify the level of TCRα or TCRβ rearrangement and preliminary data suggested negligible levels (<0.2%). Using a MLR assay, we demonstrate that compared to conventional CAR-T cells, API-192 secretes minimal levels of IFN-γ in response to co-culture with healthy donor peripheral blood mononuclear cells, consistent with a low graft vs host risk. In an autonomous growth assay, API-192 expands at a low level and subsequently contracts, suggesting a lack of dysregulated growth. Collectively, these results demonstrate the favorable manufacturability, potency, and safety of API-192 and its potential as a novel allogeneic therapy. Citation Format: Lanny Gov, Jiaji Yu, Maha Qubain, Saige L. Pompura, Sean D. Allen, Michael A. Christopher, Jeff Wiezorek. Preclinical development of API-192: An engineered CAR-NKT allogeneic cell therapy targeting CD19 and CD20 for the treatment of B-cell malignancies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB074.

Abstract CT070: Solid tumor patients require higher cyclophosphamide (cy) dose than multiple myeloma (MM) patients to achieve adequate lymphodepletion (LD) necessary to enable allogeneic CAR-T expansion

Abstract Introduction: Poseida is developing innovative allogeneic T stem cell memory rich CAR-T both for hematologic malignancies (HM) and solid tumors (ST) including P-BCMA-ALLO1 which targets BCMA for MM, and P-MUC1C-ALLO1 targeting MUC1-C for epithelial-derived ST. Optimal LD for allogeneic cell therapies remains to be established. Most research has focused on HM, where patients (pts) have likely undergone HSCT and are, therefore, LD experienced in contrast to ST pts. Consequently, ST pts may require higher doses of LD chemotherapy to achieve LD depth comparable to HM pts. This study sought to compare LD with higher doses of cy across our early phase 1 trials (NCT04960579/NCT05239143) which are enrolling ST and MM pts, respectively. Methods: P-BCMA-ALLO1 and P-MUC1C-ALLO1 are 3+3 phase 1 dose escalation studies enrolling heavily pre-treated pts. LD arm S used cy 300 mg/m2 + fludarabine (flu) 30 mg/m2 × 3 days, followed by CAR-T. Alternative arms tested higher cy doses: P1 (500 mg/m2) and P2 (1,000 mg/m2), both with flu. We assessed LD depth and cellular kinetics (CK) by measuring WBC, serum IL-15, and CAR-T transcripts (qPCR). Results: By Jan 4, 2024, 42 pts received P-BCMA-ALLO1 (22 in S, 13 in P1, 7 in P2), and 30 pts received P-MUC1C-ALLO1 (19 in S, 9 in P1, 2 in P2). ST pts presented with higher baseline WBC compared to MM pts with median counts of 5.7×103 vs. 4.4×103/µL. LD was less pronounced in ST pts with a median WBC nadir of 1.1×103/µL for both S and P1. In MM pts median WBC nadir was 0.6×103 for S vs. 0.2×103 for P1. For P-BCMA-ALLO1, CK at 2×106 cells/kg dose showed a mean Cmax of 130,811 copies (cp)/µg in P2 and 6,191 in P1 compared to 170 in S. Median WBC nadir was significantly (p=0.0002) lower for P2 (0.1×103/µL) compared to S (0.6×103), with corresponding AUC0-13d values of 3.5×103/µL for P2 vs. 10×103 for S (p=0.0013). Peak serum IL-15 in P2 was 66.1 pg/mL, significantly higher than 29.7 in S (p=0.0110). In P1, there was a trend towards improved LD with median WBC nadir for P1 of 0.3×103/µL and AUC0-13d of 6.4×103/µL.P1 LD for P-MUC1C-ALLO1 did not improve CK, with WBC nadir and AUC 0-13d values comparable to S. P-MUC1C-ALLO1 CK at 2×106 cells/kg showed a mean Cmax of 692 cp/µg DNA in S, 23 in P1, and 4,200 in P2. P-MUC1C-ALLO1 pts receiving P2 achieved the deepest LD (WBC nadir: 0.1×103/µL). Peak IL-15 in ST pts was increased and delayed to day 8 in P2, compared to day 0 - 1 in S or P1. Conclusion: Increasing cy dose to 500 or 1,000 mg/m2 improves CK for P-BCMA-ALLO1 pts due to enhanced LD depth. For P-MUC1C-ALLO1 pts, increasing cy to 500 does not improve LD depth or CK compared to 300. This difference suggests the need for higher LD doses in ST pts than MM pts to achieve optimal CK. This differential need for LD chemo for these two studies is unlikely due to cellular characteristics because of similar manufacturing technology with the only difference being the binder. Citation Format: Sabrina Haag, Jeff D. Eskew, Katherine McArthur, Joanne McCaigue, Sepideh Vaziri, Samuel DePrimo, Christopher E. Martin, Catherine Gregovics, Ann Murphy, Hamid Namini, Ellen Christie, Marcela Marinez-Prieto, Rajesh Belani, Stacey Cranert, Julia Coronella, Devon Shedlock. Solid tumor patients require higher cyclophosphamide (cy) dose than multiple myeloma (MM) patients to achieve adequate lymphodepletion (LD) necessary to enable allogeneic CAR-T expansion [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT070.

Abstract LB120: Stem cell-derived ACUA CAR-NKT allogeneic cell therapies harness orthogonal mechanisms of action for the treatment of solid tumors

Abstract Despite the remarkable success of chimeric antigen receptor T cell (CAR-T) therapies in treating hematological malignancies, their use in solid tumor indications has been met with distinct challenges. The immunosuppressive tumor microenvironment (TME) and tumor antigen heterogeneity are two significant factors that may adversely impact the efficacy of these ground-breaking therapies. Engineered natural killer T (NKT) cells harbor biological features distinct from CAR-T cell or CAR-NK cell therapies and thus represent a novel therapeutic approach to deploy “off the shelf” to patients. Appia Bio’s ACUA platform is capable of generating large quantities of highly pure CAR-NKT cells from cord blood CD34+ hematopoietic stem and progenitor cells (HSPCs) for clinical use. We have demonstrated that multiple distinct mechanisms of anti-tumor activity are operative in CAR-NKT cells, including CAR-mediated killing, NK receptor-mediated killing, adjuvant effects on antigen-specific T cells and immature dendritic cells, as well as the ability to deplete of pro-tumorigenic macrophages.When transduced with a CAR, ACUA-derived CAR-NKT cells show potent CAR-mediated tumor cell killing, similar to CAR-T cells. In contrast to conventional T cells, CAR-NKT cells also demonstrate potent CAR antigen-independent tumor cell killing, mediated partially through NKG2D and DNAM-1 activating NK receptors. CAR-NKT cells, but not conventional CAR-T cells, enhanced the function of NY-ESO specific T cells in controlling multiple rounds of tumor rechallenge, through the secretion of soluble components. In regard to other adjuvant effects which may provide additional benefit in vivo, ACUA-derived NKT cells enhanced the activation of peripheral blood monocyte-derived dendritic cells, which can regulate beneficial Th1 type immune responses. To explore how ACUA-derived NKT cells could reshape the TME, we generated immunosuppressive M2-polarized macrophages and observed that ACUA-derived NKT cells can either kill or reprogram these cells to a pro-inflammatory phenotype following co-culture. Notably, these immune cell adjuvant mechanisms are specific to ACUA-derived NKT cells and are not observed with conventional CAR-T cells. In summary, these mechanistic studies underscore the advantages of ACUA-derived NKT cells over conventional CAR-T cells and highlight their potential as a promising differentiated allogeneic therapy for the treatment of solid tumors. Citation Format: Xi Wang, Andrew J. Hou, Michael A. Christopher, Yannick Bulliard, Jason S. Damiano. Stem cell-derived ACUA CAR-NKT allogeneic cell therapies harness orthogonal mechanisms of action for the treatment of solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB120.

Scaling Insulin-Producing Cells by Multiple Strategies.

In the quest to combat insulin-dependent diabetes mellitus (IDDM), allogenic pancreatic islet cell therapy sourced from deceased donors represents a significant therapeutic advance. However, the applicability of this approach is hampered by donor scarcity and the demand for sustained immunosuppression. Human induced pluripotent stem cells are a game-changing resource for generating synthetic functional insulin-producing β cells. In addition, novel methodologies allow the direct expansion of pancreatic progenitors and mature β cells, thereby circumventing prolonged differentiation. Nevertheless, achieving practical reproducibility and scalability presents a substantial challenge for this technology. As these innovative approaches become more prominent, it is crucial to thoroughly evaluate existing expansion techniques with an emphasis on their optimization and scalability. This manuscript delineates these cutting-edge advancements, offers a critical analysis of the prevailing strategies, and underscores pivotal challenges, including cost-efficiency and logistical issues. Our insights provide a roadmap, elucidating both the promises and the imperatives in harnessing the potential of these cellular therapies for IDDM.

Combining CRISPR-Cas9 and TCR exchange to generate a safe and efficient cord blood-derived T cell product for pediatric relapsed AML

BackgroundHematopoietic cell transplantation (HCT) is an effective treatment for pediatric patients with high-risk, refractory, or relapsed acute myeloid leukemia (AML). However, a large proportion of transplanted patients eventually die due...

Abstract 1333: Preclinical data supporting the Phase 1 trial design of SENTI-202, a next generation allogeneic logic-gated selective CAR NK cell therapy, engineered to overcome key limitations of first generation cell therapies in AML

Abstract First generation natural killer (NK) and chimeric antigen receptor (CAR) NK cell products are well-tolerated and have clinical activity (~20-60% CR) in patients with AML. CRs generally increase with the inclusion of CARs or cytokines, increased cell doses, and when Flu/Ara-C lymphodepletion (LD) is used for conditioning. Key clinical limitations have been low PK of the infused NK cells, short durability of the observed responses potentially due to immune evasion of leukemic stem cells (LSCs), and manufacturing challenges precluding higher or multiple doses. SENTI-202 is a next generation allogeneic logic-gated selective CAR NK cell therapy specifically designed to address these limitations and to augment endogenous NK anti-AML activity. SENTI-202 expresses a bivalent activating CAR (aCAR) that targets CD33 and FLT3 on bulk AML blasts and LSCs. As FLT3 is also expressed on healthy hematopoietic stem cells (HSCs), SENTI-202 is further engineered to express an inhibitory CAR that recognizes endomucin expressed on HSCs, thereby conferring protection from aCAR-mediated cytotoxicity even in the presence of FLT3/CD33. SENTI-202 expresses a calibrated-release IL15 that provides both auto- and paracrine cytokine support, mediating expansion, activation, and persistence of SENTI-202 and host immune cells. SENTI-202 demonstrated robust and specific killing of primary AML blasts, LSCs, and AML cell lines in vitro. SENTI-202 protected HSCs from CAR-mediated cytotoxicity while preserving their function. In vivo, SENTI-202 revealed robust efficacy that increased with higher E:T ratio and with 3 weekly vs 1 dose. Preclinically, 3 doses of SENTI-202 that were > 60-fold the planned starting clinical trial dose were well tolerated in acute and chronic toxicology studies with no CAR NK-related body weight, laboratory, or histopathology findings. SENTI-202 non-clinical PK revealed greater than dose proportional exposure, which was ~2-fold greater compared to non-engineered NK cells. Pretreatment of CD33/FLT3 negative AML cell lines with Ara-C resulted in upregulation of CD33 and FLT3 expression, sensitizing cells to robust SENTI-202-mediated killing, providing additional rationale for the use of Ara-C-based LD. In the presence of exogenous IL2, persistence, cytotoxicity, and serial killing activity of SENTI-202 were increased, supporting the use of low dose IL2 to further augment SENTI-202 clinical activity. Taken together, these results support the Phase 1 trial design of SENTI-202-101 in patients with R/R CD33 and/or FLT3 positive malignancies including AML, which uses Flu/Ara-C as LD followed by 3 weekly doses of SENTI-202 and includes the option of enrolling patients into cohorts that additionally receive low dose IL2 following SENTI-202 administration. Citation Format: Deepika Kaveri, Pearley Chinta, Elizabeth Leitner, Lawrence Naitmazi, Gozde Yucel, Mengxi Tian, Niran Almudhfar, Han Deng, Yongshuai Li, Alice Lam, Chen-Ting Lee, Enping Hong, Rochelle Emery, Brian Garrison, Aaron N. Nguyen, Kanya Rajangam. Preclinical data supporting the Phase 1 trial design of SENTI-202, a next generation allogeneic logic-gated selective CAR NK cell therapy, engineered to overcome key limitations of first generation cell therapies in AML [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 1333.