EDIT-301: An Experimental Autologous Cell Therapy Comprising Cas12a-RNP Modified mPB-CD34+ Cells for the Potential Treatment of SCD

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 4636-4636
Author(s):  
Edouard De Dreuzy ◽  
Jack Heath ◽  
John A Zuris ◽  
Patricia Sousa ◽  
Ramya Viswanathan ◽  
...  

Sickle cell disease (SCD) is an inherited blood disorder affecting approximately 100,000 individuals in the United States. Fetal hemoglobin (HbF) is a major modifier of SCD severity. Studies showed that individuals with compound heterozygosity for sickle hemoglobin (HbS) and hereditary persistence of fetal hemoglobin (HPFH) that expressed approximately 30% HbF did not show features of SCD. Therefore, we are developing EDIT-301, an experimental autologous cell therapy comprising CD34+ cells genetically modified using a Cas12a RNP (ribonucleoprotein) to promote HbF expression to treat SCD. Several HPFH mutations have been reported at the HBG locus. In particular, disruption of the distal CCAAT-box region of the HBG1/2 promoters was associated with elevated levels of HbF, suggesting that this region is a relevant genome editing target for the treatment of SCD. Genotype to phenotype analysis at the distal CCAAT-box region of the HBG1/2 promoters identified the mutations leading to elevated HbF expression. Indels disrupting more than 3 nucleotides were generally associated with elevated HbF expression while smaller indels had lower to no impact. We evaluated editing at this site using several RNP configurations, based on either SpCas9 or Cas12a (also known as Cpf1). Cas12a RNP resulted in larger deletions and a higher frequency of productive indels than SpCas9 RNP. Furthermore, productive indels generated with SpCas9 RNP relied predominantly on microhomology mediated end joining (MMEJ) mechanism. As the MMEJ repair mechanism is not frequently used by hematopoietic stem cells (HSC), productive editing may be low in vivo. In contrast, Cas12a RNP generated more productive indels at the HBG1/2 promoters target site irrespective of the DNA repair mechanism. We therefore postulated that editing at the distal CCAAT-box region with Cas12a would better support long-term persistence of productive indels and robust HbF expression. Consistent with this hypothesis, 80-90% editing was observed after electroporation of mobilized peripheral blood CD34+ cells (mPB-CD34+ cells) from healthy donors with a Cas12a RNP targeting the HBG1/2 promoters, resulting in approximately 40% of HbF expression in their erythroid progeny. Infusion of the modified CD34+ cells into NBSGW mice resulted in long-term multi-lineage reconstitution at 16 weeks post-infusion, with no reduction in editing levels compared to those at the time of infusion. A diverse on-target editing profile was observed in all animals, indicative of a polyclonal engraftment. Erythroid cells purified from the bone marrow of animals that received Cas12a-RNP treated cells demonstrated robust HbF expression averaging 40-50% compared to ~5% observed in the vehicle-treated control group. Off-target activity of the Cas12a RNP was also evaluated. A set of candidate off-target sites was first determined using orthogonal methods, including: in-silico prediction, Digenome-Seq and GUIDE-Seq. Each candidate site was then analyzed for editing by targeted PCR-NGS in electroporated CD34+ cells. No off-target editing was verified, demonstrating the specificity of this Cas12a RNP. Taken together, we identified a specific Cas12a RNP that efficiently edited the distal CCAAT-box region at the HBG1/2 promoters in CD34+ cells. These edited CD34+ cells led to long-term polyclonal multilineage engraftment and therapeutically meaningful levels of 40-50% HbF in vivo. Based on these results, IND-enabling activities have been initiated for EDIT-301: an experimental autologous cell therapy comprising Cas12a-RNP modified mPB-CD34+ cells for the potential treatment of SCD. Disclosures De Dreuzy: Editas Medicine Inc.: Employment, Equity Ownership. Heath:Editas Medicine Inc.: Employment, Equity Ownership. Zuris:Editas Medicine Inc.: Employment, Equity Ownership. Sousa:Editas Medicine Inc.: Employment, Research Funding. Viswanathan:Editas Medicine Inc.: Employment, Equity Ownership. Scott:Editas Medicine Inc.: Employment, Equity Ownership. Da Silva:Editas Medicine Inc.: Employment, Equity Ownership. Ta:Editas Medicine Inc.: Employment, Equity Ownership. Capehart:Editas Medicine Inc.: Equity Ownership. Wang:Editas Medicine Inc.: Employment, Equity Ownership. Fernandez:Editas Medicine Inc.: Employment, Equity Ownership. Myer:Editas Medicine Inc.: Employment, Equity Ownership. Albright:Editas Medicine Inc.: Employment, Equity Ownership. Wilson:Editas Medicine Inc.: Employment, Equity Ownership. Teixeira:Editas Medicine Inc.: Employment, Equity Ownership. Chang:Editas Medicine Inc.: Employment, Equity Ownership.

Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 45-46
Author(s):  
Edouard De Dreuzy ◽  
Jack Heath ◽  
Patricia Sousa ◽  
Tusneem Janoudi ◽  
Harry An ◽  
...  

Sickle cell disease (SCD) is an inherited blood disorder affecting approximately 100,000 individuals in the United States. As fetal hemoglobin (HbF) has been shown to be protective against clinical manifestation of SCD, we are developing EDIT-301, an autologous cell therapy comprising CD34+ cells genetically modified using a Cas12a ribonucleoprotein (RNP) to promote HbF expression to treat SCD. Fetal hemoglobin induction for EDIT-301 is achieved by disrupting the HBG1 and HBG2 promoter distal CCAAT-box region where naturally occurring mutations are found to be associated with elevated HbF expression. Cas12a was selected over Cas9 due to the more productive and sustainable (NHEJ derived) indel profile, as well as high specificity. Using Cas12a RNP, on-target editing of ~90% was achieved in mobilized peripheral blood CD34+ cells (mPB-CD34+ cells) from both healthy and SCD donors at research scale with no detectable off targets. Editing of CD34+ cells led to an average of 43% and 54% of HbF expression in the erythroid progeny of normal donor and SCD donor cells respectively in a pancellular fashion (~93% population). The robust HbF induction in SCD red blood cells (RBCs) resulted in significant phenotypic and functional improvement including reduced sickling and increased deformability under hypoxia ex vivo. Using a microfluidic assay that replicated blood flow in microvasculature under varying oxygen conditions, SCD RBCs derived from RNP electroporated CD34+ cells showed improved rheological behavior. The rheology improvement under hypoxia was strongly correlated with the increased levels of HbF in each sample. Infusion of the modified CD34+ cells from normal donors into NBSGW mice resulted in long-term multi lineage and polyclonal reconstitution. Editing levels at 16 weeks post infusion were > 90% in all human lineages tested, demonstrating the efficient editing of SCID-repopulating hematopoietic stem cells (HSCs). Consistent with the high editing levels, human erythroid cells from the bone marrow of mice that received Cas12a-RNP treated cells demonstrated pancellular (~90% F+ RBCs) HbF expression averaging 40-50% of total hemoglobin compared to ~5% HbF observed in the control group. We have developed a consistent large-scale process using functionally closed, semi-automated systems suitable for use in clinical manufacturing. We have shown robust editing of normal donor CD34+ cells and SCID-repopulating HSCs with the clinical scale process. Editing levels of >90% were detected after long term engraftment in mice. In summary, we have demonstrated successful on-target editing of mPB CD34+ cells derived from both normal and SCD donors using a Cas12a RNP, which coincided with robust HbF induction and a phenotypic reduction of sickling in the SCD erythroid progeny, as well as improved rheological behavior. Editing of the HBG1 and HBG2 promoters using this RNP was highly specific with no measurable off-target. In vivo, cells from normal donors readily engrafted and reconstituted all blood cell lineages at levels comparable to unedited cells. Finally, a robust large-scale manufacturing process has been developed to supply material for the clinical setting. Based on these results, we are completing the activities required to assess EDIT-301 in the clinic as treatment for SCD. Disclosures De Dreuzy: Editas Medicine Inc.: Current Employment, Current equity holder in publicly-traded company. Heath:Editas Medicine Inc.: Current Employment, Current equity holder in publicly-traded company. Sousa:Editas Medicine Inc.: Current Employment, Current equity holder in publicly-traded company. Janoudi:Editas Medicine Inc.: Current Employment, Current equity holder in publicly-traded company. An:Editas Medicine Inc.: Current Employment, Current equity holder in publicly-traded company. Albright:Editas Medicine Inc.: Current Employment, Current equity holder in publicly-traded company. Teixeira:Editas Medicine Inc.: Current Employment, Current equity holder in publicly-traded company. Monesmith:Editas Medicine Inc.: Current Employment, Current equity holder in publicly-traded company. Zhang:Editas Medicine Inc.: Current Employment, Current equity holder in publicly-traded company. Chang:Editas Medicine Inc.: Current Employment, Current equity holder in publicly-traded company.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 2637-2637
Author(s):  
Yagna PR Jarajapu ◽  
Sergio Caballero ◽  
Li Liu ◽  
Vinayak Shenoy ◽  
Michael J Katovich ◽  
...  

Abstract Abstract 2637 Purpose: RAS plays a vital role in regulating many physiological processes of the vascular system. Angiotensin II (Ang II), a product of angiotensin converting enzyme (ACE), mediates its effects through activation of either the AT1 receptor – to induce vasoconstriction, proliferation, fibrosis, and inflammation – or the AT2 receptor to promote NO generation. The protective arm of RAS involves ACE2, which produces angiotensin-(1-7) [Ang-(1-7)]. Ang-(1-7) activates the MAS receptor to promote vascular health. Because diabetic endothelial progenitor cells are dysfunctional and this limits their utility in autologous cell therapy, we asked whether angiotensin (Ang)-(1-7) could restore the vasoreparative function of diabetic CD34+cells. Methods: Healthy nondiabetic (ND) and diabetic (D) Lin−CD45midCD34+ cells were obtained from peripheral blood mononuclear cells (PB-MNCs) by FACS. The effect of Ang-(1-7) on migration, proliferation, NO bioavailability, reactive oxygen species (ROS) levels and NADPH oxidase activity were evaluated in ND- and D-CD34+ cells. The effect of Ang-(1-7) on the formation of ECFCs from ND- and D-MNCs was evaluated. Ang-(1-7) production by cells was analyzed and the expression of ACE2 and Mas-receptor were assessed by real-time PCR and flow cytometry. Effects of ACE2 activators XNT and DIZE in CD34+ cells were also evaluated. D-CD34+ cells were genetically modified to overexpress Ang-(1-7) by lentiviral Ang-(1-7)-fusion transgene and their function was evaluated in vitro. The effect of transduction on the surface expression of CD133, CD34 and CD309 was assessed. In vivo homing function was assessed in a mouse model of ischemia-reperfusion (I/R). After one week of I/R insult, when retinal capillary damage was appreciable, CD34 cells were intravitreally injected. Neural retinas were harvested after 48 hours and human cells within the mouse vasculature were localized by immunohistochemistry. Results: Migration to SDF1- and VEGF-were impaired in D-CD34+ cells. In contrast, Ang-(1-7)-induced migration in both D-CD34+ and ND-CD34+cells was dependent on Mas receptor expression and eNOS. ROS levels and NADPH oxidase activity were reduced and proliferation and NO bioavailability were restored in D-CD34+ cells by Ang-(1-7). ECFCs from D-MNCs were appeared only in the presence of Ang-(1-7). Migration, NO release and Ang-(1-7) release by ACE2 activators, XNT and DIZE, were significantly decreased in D-CD34+ cells. Ang-(1-7) release and ACE2 expression were decreased in D-cells while Mas-receptor expression was similar that in ND-cells. Ang-(1-7) gene-modified cells showed reduced ROS levels, increased NO bioavailability, enhanced migration to SDF-1 and proliferation. Lentiviral transduction did not alter surface expression of CD133, CD34 and CD309. Ang-(1-7)-overexpression restored the homing efficiency of D-CD34+ cells similar to that of ND-CD34+ cells in vivo. Conclusions: Ang-(1-7) stimulates the vasoreparative functions in CD34+ cells. Ang-(1-7) bypasses the reduced ACE2 seen in diabetic CD34+ cells and restores the vasoreparative potential of these cells by decreasing oxidative stress and normalizing NO bioavailability. Pharmacological strategies that either increase ACE2 or Ang-(1-7) in diabetic CD34+ cells will improve their therapeutic utility for autologous cell therapy in treatment of diabetic complications. Disclosures: No relevant conflicts of interest to declare


Blood ◽  
2017 ◽  
Vol 130 (Suppl_1) ◽  
pp. 659-659
Author(s):  
Kevin A. Goncalves ◽  
Megan D. Hoban ◽  
Jennifer L. Proctor ◽  
Hillary L. Adams ◽  
Sharon L. Hyzy ◽  
...  

Abstract Background. The ability to expand human hematopoietic stem cells (HSCs) has the potential to improve outcomes in HSC transplantation and increase the dose of gene-modified HSCs. While many approaches have been reported to expand HSCs, a direct comparison of the various methods to expand transplantable HSCs has not been published and clinical outcome data for the various methods is incomplete. In the present study, we compared several small molecule approaches reported to expand human HSCs including HDAC inhibitors, the aryl hydrocarbon antagonist, SR1, and UM171, a small molecule with unknown mechanism, for the ability to expand phenotypic HSC during in vitro culture and to expand cells that engraft NSG mice. Although all strategies increased the number of phenotypic HSC (CD34+CD90+CD45RA-) in vitro, SR1 was the most effective method to increase the number of NOD-SCID engrafting cells. Importantly, we found that HDAC inhibitors and UM171 upregulated phenotypic stem cell markers on downstream progenitors, suggesting that these compounds do not expand true HSCs. Methods. Small-molecules, SR1, HDAC inhibitors (BG45, CAY10398, CAY10433, CAY10603, Entinostat, HC Toxin, LMK235, PCI-34051, Pyroxamide, Romidepsin, SAHA, Scriptaid, TMP269, Trichostatin A, or Valproic Acid) and UM171 were titrated and then evaluated at their optimal concentrations in the presence of cytokines (TPO, SCF, FLT3L, and IL6) for the ability to expand human mobilized peripheral blood (mPB)-derived CD34+ cells ex vivo . Immunophenotype and cell numbers were assessed by flow cytometry following a 7-day expansion assay in 10-point dose-response (10 µM to 0.5 nM). HSC function was evaluated by enumeration of colony forming units in methylcellulose and a subset of the compounds were evaluated by transplanting expanded cells into sub-lethally irradiated NSG mice to assess engraftment potential in vivo . All cells expanded with compounds were compared to uncultured or vehicle-cultured cells. Results. Following 7 days of expansion, SR1 (5-fold), UM171 (4-fold), or HDAC inhibitors (>3-35-fold) resulted in an increase in CD34+CD90+CD45RA- number relative to cells cultured with cytokines alone; however, only SR1 (18-fold) and UM171 (8-fold) demonstrated enhanced engraftment in NSG mice. Interestingly, while HDAC inhibitors and UM171 gave the most robust increase in the number and frequency of CD34+CD90+CD45RA- cells during in vitro culture, these methods were inferior to SR1 at increasing NSG engrafting cells. The increase in CD34+CD90+CD45RA- cells observed during in vitro culture suggested that these compounds may be generating a false phenotype by upregulating CD90 and down-regulating CD45RA on progenitors that were originally CD34+CD90-CD45RA+. We tested this hypothesis by sorting CD34+CD90-CD45RA+ cells and culturing these with the various compounds. These experiments confirmed that both HDAC inhibitors (33-100 fold) and UM171 (28-fold) led to upregulation of CD90 on CD34+CD90-CD45RA+ cells after 4 days in culture. Since approximately 90% of the starting CD34+ cells were CD90-, these data suggest that most of the CD34+CD90+CD45RA- cells in cultures with HDAC inhibitors and UM171 arise from upregulation of CD90 rather than expansion of true CD34+CD90+CD45RA- cells and may explain the disconnect between in vitro HSC phenotype and NSG engraftment in vivo . This was further confirmed by evaluation of colony forming unit frequency of CD34+CD90-CD45RA+ cells after culture with compounds. Conclusions. We have showed that AHR antagonism is optimal for expanding functional human HSCs using the NSG engraftment model. We also demonstrated that UM171 and HDAC inhibitors upregulate phenotypic HSC markers on downstream progenitors. This could explain the discrepancy between impressive in vitro phenotypic expansion and insufficient functional activity in the NSG mouse model. Therefore, these data suggest caution when interpreting in vitro expansion phenotypes without confirmatory functional transplantation data, especially as these approaches move into clinical trials in patients. Disclosures Goncalves: Magenta Therapeutics: Employment, Equity Ownership. Hoban: Magenta Therapeutics: Employment, Equity Ownership. Proctor: Magenta Therapeutics: Employment, Equity Ownership. Adams: Magenta Therapeutics: Employment, Equity Ownership. Hyzy: Magenta Therapeutics: Employment, Equity Ownership. Boitano: Magenta Therapeutics: Employment, Equity Ownership, Patents & Royalties. Cooke: Magenta Therapeutics: Employment, Equity Ownership, Patents & Royalties.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 806-806
Author(s):  
Olivier Humbert ◽  
Stefan Radtke ◽  
Ray R Carillo ◽  
Anai M Perez ◽  
Sowmya Somashekar Reddy ◽  
...  

Abstract Beta-thalassemia and sickle cell disease are monogenic disorders that are currently treated by allogeneic bone marrow (BM) transplantation although the challenges of finding a suitable matched-donor and the risk of graft vs host disease have limited the adoption of this otherwise curative treatment. A potentially promising approach for hemoglobinopathies aims to reactivate fetal hemoglobin (HbF) as a substitute for defective or absent adult hemoglobin by modifying the patient's own hematopoietic stem and progenitor cells (HSPCs). Here, we evaluated CRISPR/Cas9-induced small deletions in HSPCs that are associated with hereditary persistence of fetal hemoglobin (HPFH) using our nonhuman primate (NHP) stem cell transplantation and gene therapy model. The CRISPR/Cas9 nuclease platform was employed to recapitulate a natural genetic alteration identified in individuals with HPFH, consisting of a 13-nucleotide (nt) deletion in the gamma globin gene promoter. A first cohort of three rhesus macaques received 70-75% HPFH-edited BM-derived CD34+ HSPCs. All animals showed rapid hematopoietic recovery and peripheral blood (PB) editing levels stabilized at 12-30% for at least a year post transplantation (Figure 1). HbF production, determined by circulating F-cells, persisted at frequencies of 8-22% and correlated with in vivo PB editing. Robust engraftment of gene-edited HSPCs in the BM compartment was observed in all animals, with no measurable off-target activity or clonal expansion. We have recently shown, that the CD34+CD90+CD45RA- phenotype is exclusively required for short- and long-term multilineage reconstitution, significantly reduces the target cell number for gene therapy/editing and is conserved between human and NHP hematopoietic cells (Radtke et al., STM, 2017). To explore this cell population further, we transplanted a second cohort of three animals by sort-purifying and solely editing this hematopoietic stem cell (HSC)-enriched CD34+CD90+CD45RA- phenotype, thus reducing the number of target cells by over 10-fold without impacting hematopoietic recovery, engraftment, or HbF reactivation. In vivo levels of gene-edited PB started at less than 5% because of the high number of co-infused unmodified progenitor cells, but rapidly increased to about 50% within 1 week (Figure 1) and stabilized at levels comparable to the CD34 cohort. This data supports our interpretation that CD34+CD90+CD45RA- cells are the main cell population relevant for long-term reconstitution and an excellent target for improved and efficient gene therapy/editing. These results demonstrate robust engraftment and persistence of CD34+ HPSCs as well as HSC-enriched CD34+CD90+CD45RA- cells that have been CRISPR/Cas9-edited at the 13nt-HPFH site, with marked and stable HbF reactivation and no overt adverse effects in a NHP transplantation and gene therapy model. Most importantly, we validated our refined CD90+ target which reduces the need for editing reagents by 90% without compromising the gene modification and engraftment efficiencies. These are the first data in a clinically relevant large animal model to demonstrate the feasibility and clinical applicability of CRISPR/Cas9-mediated fetal hemoglobin reactivation. The successful targeting and engraftment of our HSC-enriched population should also have significant implications for gene therapy and editing of other genetic diseases. Figure 1: Tracking of HPFH editing in transplanted animals. A) Editing efficiency was longitudinally determined by next generation sequencing of the targeted locus in PB white blood cells from 2 cohorts of transplanted rhesus animals. Frequency is represented as the proportion of all sequence reads containing an edited locus. B) Normalized frequency of the desired 13nt-HPFH deletion in the same animals as shown in A). Figure. Figure. Disclosures Negre: Bluebird Bio: Employment, Equity Ownership, Other: Salary. Adair:RX Partners: Honoraria; Miltenyi Biotec: Honoraria; Rocket Pharmaceuticals: Patents & Royalties: PCT/US2017/037967 and PCT/US2018/029983. Scharenberg:Generation Bio: Equity Ownership; Casebia Therapeutics: Employment; Alpine Immune Sciences: Equity Ownership. Kiem:Rocket Pharmaceuticals: Consultancy; Magenta: Consultancy; Homology Medicine: Consultancy.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 3718-3718
Author(s):  
Tracey Lodie ◽  
Julian Adams ◽  
Dima Yackoubov ◽  
Yair Steinhardt ◽  
Dorit Ashengrau ◽  
...  

Historical efforts at expansion of umbilical cord blood (UCB) derived CD34+ hematopoietic stem cells (HSCs) ex vivo with cytokines yielded large numbers of progenitors for transplantation but impaired their long-term engraftment ability. We used nicotinamide (NAM), an allosteric inhibitor of NAD-enzymes, to create omidubicel, an investigational cell therapy designed to improve the expansion of CD34+ HSCs for bone marrow transplant. A Phase 1/2 clinical study of omidubicel in patients with high-risk hematologic malignancies showed rapid neutrophil engraftment and a more favorable immune reconstitution profile in patients compared to historical controls.1 We hypothesized that NAM treatment maintains the stemness and engraftment potential of omidubicel, which is associated with clinical benefit.2 We performed transcriptome, transcription factor (TF), and pathway analysis by next generation sequencing (NGS) to discern the mechanism of action of NAM and to elucidate the pathways leading to the preservation of engraftment after ex vivo expansion of omidubicel compared to CD34+ cells grown in the absence of NAM. Transcriptome analysis revealed that treatment of CD34+ cells with cytokines alone (stem cell factor [SCF], thrombopoietin [TPO], IL-6, and FLT3 ligand) led to an increase in pathways responsible for cell proliferation and differentiation, apoptotic stress, and production of reactive oxygen species (ROS), and matrix metalloproteinases (MMPs), all of which were attenuated by NAM. TF enrichment analysis of NAM-upregulated genes and downregulated genes demonstrated that NAM modulated several TFs critically involved in pathways of HSC cell self-renewal, differentiation, apoptosis and migration. Specifically, NF-kB, C-Jun, LXR/RXR and PPARα/RXRα, and AMPK-mTor signaling were all reduced in NAM-treated CD34+ cells compared to controls. Reduced expression of key genes involved in the production of ROS and reactive nitrogen species (RNS) including NADPH-oxidase-related genes (CYBB, NCF2 and NCF4) and iNOS, suggested that NAM-expanded CD34+ cells were less exposed to oxygen and nitrogen free radical stress than controls. NAM also downregulated the expression of several matrix metalloproteinases (MMP) genes including MMP7, MMP9, MMP12 and MMP19. NAM-induced downregulation of MMPs may explain the increase in engraftment in patients receiving omidubicel. Pathway analysis of differentially expressed (DE) genes was conducted using ingenuity (IPA) software. IPA analysis of DE genes showed significant downregulation of growth factor activating pathways including SCF, TPO, FLT, and GM-CSF and Endothelin-1 and P2Y Purigenic Receptor, which was confirmed by a reduction in cell cycling rates of labeled cells. IPA analysis also pointed to genes in 3 key cellular pathways that were downregulated by NAM: stress induction of apoptosis, production of ROS and RNS, and production of MMPs. NAM treatment also uniquely upregulated genes linked to cellular metabolism including the Sirtuin family genes, TCA cycle genes, and HIF1a. Interestingly, NAM upregulated genes responsible for telomerase expression further validating our hypothesis that NAM preserves cell stemness. In summary, NGS transcriptome analysis revealed that ex vivo expansion of UCB derived CD34+ cells in the presence of NAM attenuated TFs responsible for proliferation and differentiation of stem cells. In addition, NAM treatment downregulated genes regulating the production ROS, RNS, and MMPs and upregulated genes controlling metabolism and senescence, thus allowing for the expansion of CD34+ cells with preserved function and long-term engraftment ability. Our gene expression data leads to a better understanding of the mechanisms by which NAM modulates CD34+ cells in omidubicel to preserve their function. These data provide further scientific rationale for the favorable clinical engraftment and patient outcomes observed in the Phase 1/2 clinical study of omidubicel.1 An international, randomized, multi-center Phase 3 study of omidubicel in patients with high-risk hematologic malignancies is underway.2 [1]Horwitz M.E., et. al., J Clin Oncol. 2019 Feb 10;37(5):367-374. [2] ClinicalTrials.gov identifier NCT02730299. Disclosures Lodie: Gamida Cell: Employment, Equity Ownership. Adams:Gamida Cell: Employment, Equity Ownership. Yackoubov:GAMIDA CELL: Employment, Other: unexecuted shares of the company . Peled:Gamida Cell: Employment, Equity Ownership.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 2762-2762 ◽  
Author(s):  
John M. Timmerman ◽  
Kristopher K Steward ◽  
Reiko E Yamada ◽  
Patricia A Young ◽  
Dena M. Minning ◽  
...  

Abstract Background: Interferon-alpha (IFNα) is a pleiotrophic cytokine with direct anti-tumor and immunostimulatory effects. Currently IFNα is approved for the treatment of multiple hematologic malignancies, including non-Hodgkin lymphoma (NHL). However, its clinical utility has been hindered by dose-limiting toxicitiy due to systemic activation of the interferon receptor. To overcome this limitation, we engineered anti-tumor antibody-IFNα fusion proteins to selectively increase delivery of IFN to the tumor site and reduce systemic toxicity. We previously reported that IGN002, an anti-CD20-IFNα fusion protein, exhibits enhanced complement-dependent cytotoxicity (CDC) compared to rituximab, and inhibits proliferation and induces apoptosis of human B-cell NHL (Yamada et al, ASCO 2013). We now extend these previous findings and show that IGN002 possesses enhanced antibody-dependent cell-mediated cytotoxicity (ADCC) effector function and superior in vivo anti-tumor activity against B-cell NHL, compared to rituximab. Methods: IGN002 was evaluated against a panel of human Burkitt and diffuse large B-cell lymphoma (DLBCL) cell lines. Proliferation was measured by [3 H]-thymidine incorporation, STAT1 activation by flow cytometry, ADCC by lactate dehydrogenase release using human PBMC effectors, and IFN bioactivity by encephalomyocarditis (EMC) viral protection assay. NHL xenografts were grown in SCID mice. Results: IGN002 more potently inhibited the growth of NHL cell lines expressing CD20 than rituximab or unfused IFNα. Intrinsic IFNα activity of IGN002 was reduced in viral protection and anti-proliferation assays using cells lacking CD20 expression. STAT1 activation by IGN002 was enhanced on cells expressing the target antigen, whereas a control antibody-IFNα fusion protein showed reduced STAT activation activity compared to unfused IFNα. Together, these results indicate that fusion of IFNα to the antibody results in reduced IFN effects on cells not bearing the tumor antigen target. IGN002 exhibited enhanced ADCC activity compared to rituximab against Daudi, Ramos, and Raji NHL cells in long-term (overnight incubation) assays, demonstrating both higher potency and higher maximal cytotoxicity. This result is possibly due to activation of the effector cell populations by the fused IFNα moiety, as IFN is known to activate both NK cells and monocytes. The in vivo anti-tumor efficacy of IGN002 was compared to rituximab and a control antibody-IFNα fusion protein against 10-day established Raji NHL xenografts. IGN002 was superior to both rituximab and the control fusion protein, achieving a longer median survival and higher long-term survival rate (p = 0.0015 and < 0.0001 vs. rituximab and control fusion protein, respectively). The in vivo anti-tumor efficacy of IGN002 was also compared to rituximab at three equimolar dose levels (5 mg/kg, 1 mg/kg, and 0.2 mg/kg antibody) against 10-day established Daudi NHL xenografts. IGN002 showed superior efficacy compared to rituximab at all doses (p < 0.001), achieving tumor eradication (100% long-term survival) in all mice treated at all three dose levels, whereas rituximab only delayed tumor progression. Conclusions: IGN002 demonstrated more robust direct anti-proliferative and antibody effector functions than rituximab against human NHL cells in vitro, and also showed the ability to eradicate established NHL xenografts in vivo. Against cells expressing the CD20 target antigen, IGN002 exhibited greater anti-proliferative potency than unfused IFNα. In contrast, the anti-proliferative and anti-viral potency of IGN002 was reduced against cells lacking CD20, compared to unfused IFNα. These findings support the hypothesis that tumor antigen-targeted IFN therapeutics may possess a broader therapeutic index than unfused IFNα, inhibiting tumor growth by multiple mechanisms while reducing systemic toxicity. These results support the further development of IGN002 for the treatment of B-cell NHL, and a first-in-human phase I clinical study will begin later this year in the United States. Disclosures Timmerman: Janssen: Research Funding; Bristol-Myers Squibb: Honoraria, Research Funding; Valor Biotherapeutics: Research Funding. Steward:ImmunGene, Inc.: Employment. Minning:Valor Biotherapeutics, LLC: Consultancy. Sachdev:ImmunGene, Inc.: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees. Gresser:ImmunGene, Inc.: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Valor Biotherapeutics: Membership on an entity's Board of Directors or advisory committees. Khare:Valor Biotherapeutics: Membership on an entity's Board of Directors or advisory committees; ImmunGene, Inc.: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees. Morrison:ImmunGene, Inc.: Membership on an entity's Board of Directors or advisory committees, Research Funding.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 1942-1942 ◽  
Author(s):  
Bei Bei Ding ◽  
John Dixon Gray ◽  
Nan Zhang ◽  
Yanliang Zhang ◽  
Xia Cao ◽  
...  

Background: Multiple myeloma remains an incurable malignancy of plasma cells. Adoptive transfer of chimeric antigen receptor (CAR)-expressing T cells is a promising new therapy for hematologic malignancies. B-cell maturation antigen (BCMA) is a protein that is selectively expressed by B-lineage cells, including Multiple Myeloma (MM) cells, and represents a suitable target for T cell therapy. We have developed an allogeneic T cell therapy approach utilizing genetic engineering of donor-derived T cells to express an anti-BCMA Dimeric Antigen Receptor (DAR) using a proprietary non-viral vector Knock out/knock in (KOKI) technology. Preclinical data demonstrate potent anti-tumor activity both vitro and in vivo against BCMA-expressing MM cell lines. Methods: Anti-BCMA DAR-T cells were generated through genetic engineering of T cells derived from healthy donors by inserting the anti-BCMA DAR construct into the TRAC gene locus, resulting in loss of endogenous TCR expression while expressing the DAR. Distinct DAR constructs were utilized differing only in their intracellular signaling components, namely combinations of 4-1BB, CD28, and CD3zeta. The anti-BCMA DAR-T cells were expanded and purified for subsequent preclinical studies. Using in vitro assays, the different anti-BCMA DAR-T cells were evaluated against multiple myeloma cell lines for specific cytotoxicity as well as stimulus-induced cytokine secretion and cell expansion. The in vivo anti-tumor activity was assessed using luciferase-expressing RPMI8226 cells in NSG mice in a model of disseminated disease. A single dose of anti-BCMA DAR-T cells or relevant control cells was administered, and tumor burden was assessed weekly using bioluminescence imaging. Results: After purification, the anti-BCMA DAR T cells population contained less than 1% TCR-expressing ab T cells. The DAR-positive T cell population was between 20-50%. All anti-BCMA DAR-T cells exhibited BCMA-specific activation, including cytokine production, proliferation, cytotoxicity, and in vivo tumor eradication. The DAR-T cells using a third generation signaling configuration containing components from 4-1BB, CD28 and CD3zeta signaling domains performed best overall. Conclusions: All tested anti-BCMA DAR-T cells exhibited effective anti-tumor activity. Direct comparison of different cytoplasmic signaling compositions of the DAR allowed for selection of the most potent construct, namely the anti-BCMA DAR utilizing a 3rd generation signaling domain configuration. Based on these data, further development of anti-BCMA DAR-T therapy for hematological malignancies is warranted. These allogeneic abTCR-negative anti-BCMA DAR-T cells have been selected for clinical development. Disclosures Ding: Sorrento Therapeutics, Inc.: Employment, Equity Ownership, Patents & Royalties. Gray:Sorrento Therapeutics, Inc.: Employment, Equity Ownership, Patents & Royalties. Zhang:Sorrento Therapeutics, Inc.: Employment, Equity Ownership. Zhang:Sorrento Therapeutics, Inc.: Employment, Equity Ownership, Patents & Royalties. Cao:Sorrento Therapeutics, Inc.: Employment, Equity Ownership, Patents & Royalties. Krapf:Sorrento Therapeutics, Inc.: Employment, Equity Ownership. Deng:Sorrento Therapeutics, Inc.: Employment, Equity Ownership. Wei:Sorrento Therapeutics, Inc.: Employment, Equity Ownership. Zeldis:Sorrento Therapeutics Inc: Employment, Equity Ownership. Knight:Sorrento Therapeutics, Inc.: Employment, Equity Ownership. Kaufmann:Sorrento Therapeutics, Inc.: Employment, Equity Ownership, Patents & Royalties. Ji:Sorrento Therapeutics Inc: Employment, Equity Ownership, Patents & Royalties; Celularity, Inc.: Equity Ownership, Membership on an entity's Board of Directors or advisory committees. Guo:Sorrento Therapeutics, Inc.: Employment, Equity Ownership, Patents & Royalties.


Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 3546-3546
Author(s):  
Stephen Bartelmez ◽  
Ashay Bhatwadekar ◽  
Patrick Iversen ◽  
Francis W Ruscetti ◽  
Maria Grant

Abstract Abstract 3546 Poster Board III-483 CD34+ cells from diabetic patients demonstrate reduced vascular reparative function due to decreased proliferation as well as diminished migration prowess which is largely due to lower levels of bioavailable nitric oxide (NO). We asked whether a transient TGF-β1 blockade in CD34+ cells from diabetics would improve their reparative ability given that TGF-β is a key factor modulating stem cell quiescence. Peripheral blood lin-CD34+ cells or lin-CD34+CD38+/− cells were treated ex vivo with antisense phosphorodiamidate morpholino oligomers (TGF-β1 -PMO), demonstrated to inhibit TGF-β1 protein expression in stem cells. Cells were then analyzed for cell surface TGF-β Receptor 2 (TGF-β R2) and CXCR4 expression, their ability to generate NO, their ability to migrate toward SDF-1, their ability to survive in the absence of added growth factors, and tested in vivo for their vascular reparative ability. After TGF-β1-PMO treatment, healthy and diabetic CD34+CD38+ and - cells downregulated TGF-βR2, upregulated CXCR4 expression, survived in the absence of added growth factors ex vivo and migrated more efficiently to SDF-1 compared to controls. TGF-β1-PMO treated diabetic CD34+ cells restored NO production to non-diabetic levels. In contrast, TGF-β1-PMO did not enhance NO generation in CD34+ cells from healthy subjects. Using an in vivo retinal ischemia reperfusion model, we observed that TGF-β1-PMO treatment increased the ability of both healthy and diabetic CD34+ cells to home to injured capillaries compared to control PMO treated cells. As also observed in our current study, a reduction of TGF-β1 levels in murine hematopoietic stem cells correlates with a reduction in TGF-βR2 expression which may induce proliferation in vivo. We also show that both diabetic and healthy lin-CD34+CD38+ cells express TGF-βR2 by FACS. In contrast, only healthy lin-CD34+CD38- cells expressTGF-βR2 while diabetic lin-CD34+CD38 - cells express essentially no cell surface TGF-βR2 (<5 % of cells are TGF-βR2+). Our results suggest that a transient blockade of TGF-β1 may represent a promising therapeutic strategy in restoring vascular reparative function in diabetic CD34+ cells. Disclosures: Bartelmez: BetaStem Therapeutics: Employment, Equity Ownership, Head, SRB, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding. Iversen:AVI-Biopharma: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding.


Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 4844-4844
Author(s):  
Blake Warbington ◽  
Daniel Weinstein ◽  
David Mallinson ◽  
Daria Olijnyk ◽  
Sarah Paterson ◽  
...  

Abstract Background AMR-001, an autologous CD34+ cell product derived from mini-marrow harvest, is currently undergoing Phase II trials to treat acute myocardial infarction (AMI). AMR-001 is administered to the patient by infusion via the infarct related artery within five to ten days following coronary artery stenting post AMI. At the time of infusion, it is believed that the infarct-region SDF-1 (stromal derived factor) levels are peaked and scar formation has not yet occurred. It was found that, in addition to the quantity of CD34+ cells infused, improvement in cardiac perfusion and infarct size correlated with the mobility potential of CD34+ cells mediated by a SDF-1 gradient (Quyyumi et al, Am Heart J 2011, 161:98–105). We have developed a cell based in vitro mobility assay as a potential potency release assay for AMR-001. However, this assay is not suitable for a Phase III or commercial scale release assay due to the length of the assay, high skill level required to perform, and variability. To develop a more robust assay, we have initiated a study to identify potential microRNAs (miRNAs) that may be used as biomarkers for CD34+ cell SDF-1 driven migration. Our preliminary results suggest CD34+ cells with different mobility potentials may be characterized by miRNA fingerprinting. Methods Cryopreserved purified CD34+ cells derived from bone marrow of healthy donors were purchased from a commercial vendor. Thawed CD34+ cells were washed and the cells were assayed in an in vitro transwell system (Jo et al, J Clin Invest 2000, 105:101-111). The trans-membrane migration of CD34+ cells into the lower chamber in the presence of SDF-1, as well as the non-mobilized CD34+ cells in the upper chamber, were collected after 4 hours incubation at 37°C. Total RNA of the cells was isolated and the miRNA expression profile was analyzed using SurePrint G3 Human v16 microRNA 8x60K microarray slide (Agilent, Santa Clara, CA). A normalization algorithm was used to generate miRNA expression profiles (SistemQC™, Sistemic, Ltd) for the characterization of untreated cells, the mobilized population that migrate towards SDF-1, and non-mobilized population; from two independent donors. Results Two hundred and four (204) miRNAs were reliably detected across the cell samples. The mobilized cells had different miRNA profiles compared with non-mobilized/untreated cells. Hierarchical cluster analysis showed that mobilized cells grouped separately from the non-mobilized/untreated cells. Conclusion Analysis of the miRNA profiles of the CD34+ cells across two independent donors, identified a number of key miRNAs (kmiRs™) that represent possible markers for a mobility phenotype. Additional samples will be analyzed to confirm these preliminary findings. This approach will enable the identification of markers associated with mobility potential of CD34+ cells and the potential development of a molecular biomarker assay for potency. Disclosures: Warbington: Progenitor Cell Therapy, LLC: Employment. Weinstein:Progenitor Cell Therapy, LLC: Employment. Mallinson:Sistemic, Ltd.: Employment, Equity Ownership. Olijnyk:Sistemic, Ltd.: Employment. Paterson:Sistemic, Ltd.: Employment. Ridha:Sistemic, Ltd.: Employment. O'Brien:Sistemic, Ltd.: Employment, Equity Ownership, Membership on an entity’s Board of Directors or advisory committees. Lin:Progenitor Cell Therapy, LLC: Employment. LeBlon:Progenitor Cell Therapy, LLC: Employment. Fong:NeoStem, Inc.: Employment. Chan:Progenitor Cell Therapy, LLC: Employment.


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