scholarly journals Nicotinamide (NAM) Modulates Transcriptional Signature of Ex Vivo Cultured UCB CD34+ Cells (Omidubicel) and Preserves Their Stemness and Engraftment Potential

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 3718-3718
Author(s):  
Tracey Lodie ◽  
Julian Adams ◽  
Dima Yackoubov ◽  
Yair Steinhardt ◽  
Dorit Ashengrau ◽  
...  
Keyword(s):  
Stem Cells ◽  
Ex Vivo ◽  
Phase 1 ◽  
Hematologic Malignancies ◽  
Employment Equity ◽  
Cd34 Cells ◽  
Proliferation And Differentiation ◽  
Equity Ownership ◽  
Upregulated Genes

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.

Vitamin D3 Analog Inecalcitol Synergizes Vith Imatinib To Inhibit Selectively The Growth Of Chronic Myeloid Leukemia (CML) Progenitors and Stem Cells

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 3981-3981
Author(s):  
Ali G Turhan ◽  
Marie Laure Bonnet ◽  
Bouneau Clementine ◽  
Remi Delansorne ◽  
Jean-François Dufour-Lamartinie ◽  
...  
Keyword(s):  
Stem Cells ◽  
Synergistic Effect ◽  
Board Of Directors ◽  
Vitamin D3 ◽  
Myeloid Leukemia ◽  
Employment Equity ◽  
Advisory Committees ◽  
Cd34 Cells ◽  
Equity Ownership

Abstract Tyrosine kinase inhibitor (TKI) therapies which are the first line drugs in chronic myeloid leukemia (CML) have profoundly changed the prognosis of the disease and prolonged survival. However, it is clear that TKI are not able to eradicate efficiently the most primitive leukemic cells, due to their quiescence or oncogene-independence. It would therefore be of major interest to determine if compounds targeting CML progenitors / stem cells can be used in combination with TKI. Inecalcitol (19, nor 14 epi 23-yne-1,25 (OH)2D3) (ICC) is a vitamin D3 analog which has been shown to exert antiproliferative effects in several types of experimental tumors. As compared to calcitriol, the active for of natural vitamin D3, ICC has been shown to induce less hypercalcemia in vivo in mice and a higher differentiation inducing effect. The effects of ICC in primary CML progenitors and stem cells has not been tested so far. We first studied the effects of ICC on the U937 cell line as this cell line is a model responsive to the differentiation-inducing effects of vitamin D3. We have previously generated U937 cell lines expressing BCR–ABL (Ahmed et al, Leukemia Lymphoma, 2001). The effects of ICC were tested in these cells at day +2, +4 and +7 of culture using ICC at the dose of 5 nM and by the assessment of differentiation based on the morphology and the appearance CD11b and CD14 markers in flow cytometry. In dose-response experiments, we have cultured U937 cells in the presence of 1, 2 and 5 nM of ICC and we have established that the concentration of 5 nM was the most efficient in terms of differentiation induction. In cell kinetics experiments, culture of U937Neo cells as compared to U937-BCR-ABL cells, ICC alone ( 5nM) induced a similar differentiation effect with 45% of control cells and 30% of BCR-ABL cells expression CD11b at day 2, respectively and 30 % of both expressing CD11b at day 5. ICC induced the expression of CD14 at day 2 and day 4 with similar efficiencies, suggesting that BCR-ABL did not interfere with the differentiation inducing effect of ICC. In parallel with the differentiation effect, the cell mortality increased as compared to non-treated cells by 15% at day 5. To determine the effects of ICC in CML progenitors, we have used ICC alone at 1 nM and 5 nM final concentrations and established that the latter had the most inhibitory effect on CD34+ derived colony-forming-cell (CFC) growth (25% and 50% reduction as compared to untreated control n= 2 exp). In further experiments, CD34+ cells isolated from CML patients at diagnosis (n= 5) were tested in clonogenic assays (500 CD34+ cells / dish in triplicates) using a combination of ICC (5 nM) and Imatinib Mesylate (IM) which was used either at a concentration of 0.2 or 0.5 mM. In all CML samples (n= 5) there was a synergistic effect of the combination of IM and ICC, either at IM 0.2 mM and ICC 5nM ( 17% CFC survival n= 2) or IM 0.5 mM and ICC 5nM concentrations (10% CFC survival, n=3). On the other hand, this combination did not inhibit clonogenic cell growth from normal control CD34+ cells tested in the same conditions either with ICC alone at 5 nM ( 111% mean CFC survival as compared to untreated controls n= 3) or in combination of ICC 5 nM and IM 0.5 mM ( 100 % CFC survival n= 3). We have then used CD34+ cells from CML (n=2) and control ( n= 2) CD34+ cells to test the effects of ICC and IM in long-term culture initiating cell (LTC-IC) assays. Long-term cultures were started using 4.104 cells on MS5 cell stroma in three conditions by adding IM 0.5 mM, ICC 5nM or the combination of both in cultures, with weekly half-medium changes during which drugs were added to cultures in replaced medium. At week+5 cultures were terminated and LTC-IC progeny was evaluated. The numbers of non-adherent cells collected from long-term cultures were reduced significantly in the presence of IM and ICC in CML samples. A similar pattern of inhibition was also observed in control CD34+ cultures but in terms of clonogenic activity at week 5, there was a slightly higher inhibition of LTC-IC-derived CFC numbers (n=2) in CML. Thus, these results establish that ICC, a clinically used derivative of vitamin D3 has a clear activity in CML progenitors by itself and a major synergistic effect with Imatinib. The combination is not toxic to normal progenitors. This would suggest that ICC could be used in clinical setting, especially if in future experiments, a synergistic effect could be observed with more potent second generation TKI such as Nilotinib and Dasatinib. Disclosures: Turhan: Bristol Myers Squibb, Novartis: Consultancy, Honoraria. Delansorne:Hybrigenics: Employment, Equity Ownership. Dufour-Lamartinie:Hybrigenics: Employment, Equity Ownership. Guerci-Bresler:Novartis : Honoraria, Membership on an entity’s Board of Directors or advisory committees; Bristol Myers Squibb: Honoraria, Membership on an entity’s Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity’s Board of Directors or advisory committees; AMGEN: Honoraria.

scholarly journals Ex Vivo Activity of Immunotherapeutic Approaches Targeting CD38 Against Daratumumab-Resistant Multiple Myeloma Patient Samples

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 1848-1848
Author(s):  
Maria Karvouni ◽  
Heyue Zhou ◽  
Arnika Kathleen Wagner ◽  
Qiangzhong Ma ◽  
Alamdar H. Baloch ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Nk Cells ◽  
Therapeutic Potential ◽  
Ex Vivo ◽  
Phase 1 ◽  
Employment Equity ◽  
Multiple Myeloma Patient ◽  
Myeloma Cells ◽  
Car T ◽  
Equity Ownership

Background: Multiple myeloma (MM) is a plasma cell malignancy that remains incurable. The identification of CD38, a transmembrane glycoprotein overexpressed on MM cells, led to the development of target-specific therapeutics such as the FDA approved monoclonal antibody (mAb) Daratumumab (DARA). Although a valuable treatment option for refractory/relapsed (R/R) MM patients, DARA has a limited response rate of below 50%, which highlights the clinical need for novel therapeutics. Aims: Aiming to further exploit the therapeutic potential of CD38 in the MM setting, immunotherapies based on the novel anti-CD38 mAb CD38A2 were tested. Methods: For the first approach, the CD38A2 mAb -that binds to a unique, distinct from DARA's, CD38 epitope- was conjugated with either the alkylating agent Duomycin (ADC-136) or the microtubulin binder Duostatin (ADC-129). The ADCs were compared to DARA, in cultures of primary MM cells from patients refractory to DARA treatment. In a second approach, a chimeric antigen receptor (CAR) consisting of the CD38A2 scFv and the intracellular domains of CD28 and CD3ζ was used to transduce primary T and NK cells from R/R MM patients. The functionality of the CAR-T and CAR-NK cells was assessed in cytotoxicity assays against autologous myeloma cells. Results: ADC-136 demonstrated the most potent cytotoxicity against the MM cells with an IC50 of 6pM at day 6 following a single dose treatment. ADC-129 showed cell killing with an IC50 of 30pM, while DARA did not exhibit appreciable cytotoxicity. Regarding the cell therapy approach, patients' T and NK cells were effectively transduced, showing a CD38A2-CAR expression ranging between 11-68%. In functional assays, CAR-T and CAR-NK cells were assayed against autologous myeloma cells, where they exhibited an increase in target cell cytotoxicity, compared to the untransduced cells. Summary/Conclusion: Altogether, our preliminary findings demonstrate that CD38 targeting using CD38A2-based immunotherapies could be a viable therapeutic approach in R/R MM patients previously exposed to DARA. Currently, an anti-CD38 CAR-T therapy based on CD38A2 is being evaluated in Phase 1 studies in R/R MM patients by Sorrento Therapeutics, Inc. Disclosures Zhou: Sorrento Therapeutics Inc: Employment, Equity Ownership. Ma:Sorrento Therapeutics Inc: Employment, Equity Ownership. Zhu:Sorrento Therapeutics Inc: Employment, Equity Ownership. Zhang:Sorrento Therapeutics Inc: Employment, Equity Ownership. Kaufmann:Sorrento Therapeutics, Inc.: Employment, Equity Ownership, Patents & Royalties.

scholarly journals Engraftment and Retroviral Marking of CD34+ and CD34+CD38− Human Hematopoietic Progenitors Assessed in Immune-Deficient Mice

Blood ◽  
1998 ◽  
Vol 91 (4) ◽  
pp. 1243-1255 ◽  
Author(s):  
Mo A. Dao ◽  
Ami J. Shah ◽  
Gay M. Crooks ◽  
Jan A. Nolta
Keyword(s):  
Stem Cells ◽  
Ex Vivo ◽  
Human Stem Cells ◽  
Hematopoietic Stem ◽  
Human Cd34 ◽  
Cd34 Cells ◽  
Low Levels ◽  
Ex Vivo Culture ◽  
Daunting Challenge

Abstract Retroviral-mediated transduction of human hematopoietic stem cells to provide a lifelong supply of corrected progeny remains the most daunting challenge to the success of human gene therapy. The paucity of assays to examine transduction of pluripotent human stem cells hampers progress toward this goal. By using the beige/nude/xid (bnx)/hu immune-deficient mouse xenograft system, we compared the transduction and engraftment of human CD34+progenitors with that of a more primitive and quiescent subpopulation, the CD34+CD38− cells. Comparable extents of human engraftment and lineage development were obtained from 5 × 105 CD34+ cells and 2,000 CD34+CD38− cells. Retroviral marking of long-lived progenitors from the CD34+ populations was readily accomplished, but CD34+CD38− cells capable of reconstituting bnx mice were resistant to transduction. Extending the duration of transduction from 3 to 7 days resulted in low levels of transduction of CD34+CD38− cells. Flt3 ligand was required during the 7-day ex vivo culture to maintain the ability of the cells to sustain long-term engraftment and hematopoiesis in the mice.

Use of Genome-Wide Expression Analysis to Optimize An Ex Vivo clinical Protocol for 16,16-Dimethyl Prostaglandin E2 Enhancement of Umbilical Cord Blood In Hematopoietic Stem Cell Transplantation.

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 1451-1451
Author(s):  
Caroline Desponts ◽  
David Robbins ◽  
Thuy Le ◽  
Annie Chi ◽  
Scott Thies ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Treatment Protocol ◽  
Employment Equity ◽  
Advisory Committees ◽  
Hematopoietic Stem ◽  
Biologic Activity ◽  
Genome Wide ◽  
Cd34 Cells ◽  
Equity Ownership ◽  
Genome Wide Expression

Abstract Abstract 1451 A systematic investigation was performed to optimize the treatment protocol for ex vivo incubation of human hematopoietic stem cells (HSCs) with 16,16-dimethyl prostaglandin E2 (FT1050) prior to transplantation. This protocol is part of an ongoing Phase Ib clinical trial of FT1050-enhanced double cord blood (CB) transplantation after reduced intensity conditioning. FT1050 has been previously shown in vertebrate models to improve the engraftment potential of HSCs from bone marrow (BM) and CB after a brief ex vivo treatment. In these models, treatment of BM or CB with FT1050 was performed for 1 to 2 hours at 4 °C, followed by a wash and subsequent cell infusion into the recipient (North et al. Nature 2007, Hoggatt et al. Blood 2009). Several groups have demonstrated that under these conditions, FT1050-treated cells have an engraftment advantage over vehicle treated cells. The objective of the current investigation was to identify a set of conditions that maximizes the biologic activity of FT1050. Genome-wide expression analysis and cAMP assays were used to optimize the ex vivo FT1050 treatment protocol with respect to concentration, time and temperature. Using this approach, hundreds of up- and down-regulated genes were identified in FT1050-treated CD34+ cells. These signature genes include upregulation of CXCR4, a known mediator of HSC homing via SDF-1a, and CREB, a key gene involved in cAMP signaling. Results from these experiments demonstrated that FT1050 concentrations above 10 μM did not result in increased levels of biologic activity. In terms of duration of incubation, cAMP activity reached maximal levels within 30 minutes of exposure while a 2 hour treatment period was necessary to maximize the changes in gene expression. Finally, the biologic activity of FT1050 was highly sensitive to temperature, with treatment of cells at 37 °C yielding larger changes in cAMP production and gene expression as compared to incubation of cells at 25 °C and 4 °C. The biological effects of FT1050 on subsets of CD34+ cells isolated from CB were also determined. Interestingly, the stem/progenitor subsets of CD34+ cells (Lin-CD34+CD38-CD90+CD45RA-, Lin-CD34+CD38-CD90-CD45RA- and Lin-CD34+) had a greater response to FT1050 relative to the lineage positive cells. The different conditions were also evaluated using CFU-C and 7-AAD assays. No evidence of adverse effects were observed. Based upon these findings, the ongoing clinical trial incorporates the optimized FT1050 ex vivo treatment protocol (10 μM for 120 minutes at 37 °C). Disclosures: Desponts: Fate Therapeutics, Inc.: Employment, Equity Ownership. Robbins:Fate Therapeutics, Inc.: Employment, Equity Ownership. Le:Fate Therapeutics, Inc.: Employment, Equity Ownership. Thies:Fate Therapeutics, Inc.: Employment, Equity Ownership. Mendlein:Fate Therapeutics, Inc.: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees. Grayson:Fate Therapeutics Inc.: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees. Multani:Fate Therapeutics, Inc.: Employment, Equity Ownership. Shoemaker:Fate Therapeutics: Employment, Equity Ownership.

Subset Analysis of Response to Treatment of Chronic Phase CML in a Phase 1 Study of Ponatinib in Refractory Hematologic Malignancies

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 602-602 ◽  
Author(s):  
Jorge E. Cortes ◽  
Hagop M. Kantarjian ◽  
Neil Shah ◽  
Dale Bixby ◽  
Michael J. Mauro ◽  
...  
Keyword(s):  
Board Of Directors ◽  
Median Time ◽  
Research Funding ◽  
Phase 1 ◽  
Chronic Phase ◽  
Hematologic Malignancies ◽  
Employment Equity ◽  
Advisory Committees ◽  
Mutation Status ◽  
Equity Ownership

Abstract Abstract 602 Background: Ponatinib is a potent, oral, pan-BCR-ABL inhibitor active against the native enzyme and all tested resistant mutants, including the uniformly resistant T315I mutation. Initial findings of a phase 1 trial in patients (pts) with refractory hematologic malignancies have been reported. The effect of duration of treatment, prior treatment, and mutation status on response to treatment was examined in CML chronic phase (CP) pts who responded to ponatinib. Methods: An open-label, dose escalation, phase 1 trial of ponatinib in pts with hematologic malignancies is ongoing. The primary aim is to assess the safety; anti-leukemic activity is also being investigated. Pts resistant to prior treatments or who had no standard treatment available were enrolled to receive a single daily oral dose of ponatinib (2 mg to 60 mg). Subset analyses of factors impacting cytogenetic and molecular response endpoints (MCyR and MMR) were performed for pts with CP-CML. Data are presented through April 15, 2011. Results: In total, 81 pts (54% male) received ponatinib. Overall, 43 pts had CP with 34 ongoing at analysis. MCyR was observed as best response in 31/43 (72%), 27 (63%) CCyR. The median time to MCyR was 12 (3 to 104) wks. Response rates were assessed by duration of treatment (1 pt in CCyR at entry was excluded; 6 pts in PCyR had to achieve CCyR). At the 3 month assessment, 22/42 (52%) CP pts achieved MCyR; at 6 months, 24/42 (57%); at 12 months, 29/42 (69%) had MCyR. The impact of prior treatment on response and time to response was assessed. 42 pts (98%) had >2 prior TKIs and 28 (65%) ≥3 prior TKIs, including investigational agents. Of approved TKIs, all pts were previously treated with imatinib, 19 dasatinib or nilotinib after imatinib, and 21 both dasatinib and nilotinib after imatinib. MCyR rate decreased with number of prior TKIs (2 prior TKIs 13/14 [93%], ≥3 prior TKIs 17/28 [61%]) and number of approved TKIs (imatinib followed by dasatinib or nilotinib 17/19 [90%], or by both dasatinib and nilotinib 12/21 [57%]). Time to response was prolonged in pts more heavily treated with prior TKIs. Median time to MCyR increased with the number of prior TKIs and approved TKIs (2 TKIs 12 wks, ≥3 TKIs 32 wks). The effect of mutation status on response and time to response was also evaluated. At entry, 12 pts had the T315I mutation, 15 had other BCR-ABL kinase domain mutations, 12 had no mutations detected, 4 did not allow sequencing. MCyR response rate for CP pts with T315I was 11/12 (92%); for other mutations, 10/15 (67%); and no mutation, 7/12 (58%). Similarly, mutation status had an impact on time to response: median time to MCyR was 12 wks for those with T315I or other mutations and 32 wks in resistant pts with no mutation. All CP patients were evaluable for MMR. At analysis, MMR was 17/43 (40%). MMR rate was inversely related to number of prior TKIs (2 TKIs 10/14 [71%], ≥3 TKIs 6/28 [21%]), approved TKIs (imatinib followed by dasatinib or nilotinib 12/19 [63%], or by both dasatinib and nilotinib 4/21 [19%]), and was higher for T315I pts (7/12, 58%) and those with other mutations (7/15, 47%) compared with no mutation (2/12, 17%). Median time to MMR for CP pts was 97 wks; median time to MMR was shorter for pts who were less heavily treated (2 prior TKIs 24 wks) and those with T315I or other mutations (63 wks). Conclusion: In this subset analysis of the phase 1 data, ponatinib had substantial activity in all subgroups analyzed. Time on treatment, less prior therapy and kinase domain mutations were associated with higher response rates and early responses in CP pts. Cytogenetic responses improved over the first 12 months of treatment and were higher in less heavily treated pts. Disclosures: Cortes: Novartis: Consultancy, Research Funding; BMS: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; Ariad: Consultancy, Research Funding. Kantarjian:Novartis: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; BMS: Consultancy, Research Funding; ARIAD: Research Funding. Shah:Ariad: Consultancy, Research Funding. Bixby:Novartis: Speakers Bureau; BMS: Speakers Bureau; GSK: Speakers Bureau. Mauro:ARIAD: Research Funding. Flinn:ARIAD: Research Funding. Hu:ARIAD: Employment. Clackson:ARIAD: Employment, Equity Ownership. Rivera:ARIAD: Employment, Equity Ownership. Turner:ARIAD: Employment, Equity Ownership. Haluska:ARIAD: Employment, Equity Ownership. Druker:MolecularMD: OHSU and Dr. Druker have a financial interest in MolecularMD. Technology used in this research has been licensed to MolecularMD. This potential conflict of interest has been reviewed and managed by the OHSU Conflict of Interest in Research Committee and t. Deininger:BMS: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Ariad: Consultancy, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene: Research Funding; Genzyme: Research Funding. Talpaz:ARIAD: Research Funding.

A Phase I Study Of KB004, a Novel Non-Fucosylated humaneered® Antibody, Targeted Against The Receptor Tyrosine Kinase EphA3, In Advanced Hematologic Malignancies

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 3838-3838 ◽  
Author(s):  
Jeffrey E Lancet ◽  
Andrew H Wei ◽  
Simon TS Durrant ◽  
Mark S. Hertzberg ◽  
Ronan T. Swords ◽  
...  
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Phase 1 ◽  
Hematologic Malignancies ◽  
Clinical Activity ◽  
Sustained Remission ◽  
Eligibility Criteria ◽  
Bone Marrow Biopsies ◽  
Equity Ownership ◽  
Dose Levels

Abstract Background EphA3 is involved in cell positioning in fetal development. In the adult it is an oncofetal antigen re-expressed in hematologic malignancies (blood and bone marrow, leukemic stem cells) and solid tumors (tumor stem cells, neovasculature and stroma) and may be prognostic. KB004 is a humaneered® high affinity antibody targeted against EphA3 with 3 putative mechanisms of action: direct induction of apoptosis in tumor cells, activation of ADCC and disruption of tumor vasculature by induction of endothelial cell rounding and subsequent blood vessel infarction. Herein, we describe results of an ongoing, phase 1 dose-escalation study of KB004 in adult patients with advanced hematologic cancers. Objectives 1) primary: to determine safety and MTD for KB004 in patients with hematologic malignancies refractory to or unfit for chemotherapy; 2) secondary: to examine PK profile, immunogenicity, and clinical activity of KB004. Exploratory objectives include evaluation of EphA3 expression on tumor, stromal, and endothelial cells. Methods This is a multicenter phase 1 study. Key eligibility criteria include: 1) relapsed or refractory hematologic malignancy 2) ECOG PS 0-1; 3) adequate end-organ function. Additional eligibility criteria amended later to protect against hemorrhagic events, included platelets ≥ 10,000/uL (untransfused) and normal coagulation times. A standard 3 + 3 escalation study design (amended to allow up to 6 pts. per cohort in the absence of a DLT) was utilized. KB004 was administered as a 1 or 2 hr infusion on days 1, 8, and 15 of each 21-day cycle, at incremental doses of 20, 40, 70, 100, 140, 190, 250 mg and thereafter 33% increments up to a planned maximum of 700 mg. At 70 mg and above infusion reaction (IR) prophylaxis included an H1 blocker, H2 blocker, acetaminophen and IV steroids. Peripheral blood and bone marrow biopsy specimens for PK analysis and EphA3 expression, respectively, were collected during cycle 1. Results To date, 37 patients (AML 32, MDS 2, lymphoma 1, myelofibrosis 2) received KB004; 20 mg: 9 pts, 40 mg: 3pts, 70 mg: 8 pts, 100 mg: 7pts, 140 mg: 5pts, 190 mg 5pts. At 70 mg, two patients had intracranial hemorrhages 5 and 18 days after last KB004 dose in the context of thrombocytopenia and hyperleukocytosis. A causal relationship to KB004 could not be excluded. One occurred in course 1 and was considered a DLT. KB004 blood levels were near the limit of quantitation at 48 and 96 hours. Following the change to entry criteria no further episodes of serious bleeding or other DLTs or significant changes in soluble clotting factors have been observed. Overall KB004 is well tolerated. The most common toxicity was mild to moderate transient IRs in 28 (76%) patients characterized by chills, elevated temperature, fever, rigors, back pain, nausea, vomiting, hypotension, hypertension, transient hypoxia (in 2 cases). Fourteen % of infusions were slowed due to an adverse event, two (1.2%) were prematurely discontinued but no patient discontinued KB004 secondary to an IR. No other significant KB004-related toxicity has been observed. KB004 Cmax at all dose levels was above the predicted effective concentration (1 ug/ml) and was approximately dose proportional. However at dose levels below 190 mg sustained exposure to cover the entire interval between doses was not achieved. One CRp was observed at the 20mg dose level in a 78 yr-old patient with relapsed AML, who remains on study and in sustained remission for over a year. Serial bone marrow biopsies with KB004 treatment show decreased reticulin and collagen fibrosis. A > 50% reduction in marrow blast percentage was seen in 14% of AML patients, and 59% had overall stable disease beyond 1 cycle. Bone marrow biopsies positive for EphA3 expression with a cut-off of 10% of nucleated cells were obtained in 75% of AML patients. EphA3 was expressed in at least 30% of nucleated cells in the baseline sample of the patient with an ongoing CRp. Conclusion KB004 is a novel agent targeted against EphA3 that is well tolerated with evidence of clinical activity. It is anticipated that 190 mg given over 2 hours will provide sufficient plasma exposure to achieve sustained efficacy over the interval between doses. The study is ongoing. Additional PK, PD, and clinical data will be presented. Disclosures: Durrant: KaloBios: Research Funding. Yarranton:KaloBios: Employment, Equity Ownership; Glaxo: Equity Ownership; EnGen: Equity Ownership, Science Advisor, Science Advisor Other; StemLine Therapeutics: Equity Ownership. Walling:KaloBios: Consultancy; Corcept Therapeutics: Consultancy; Prothena: Consultancy; New Gen Therapeutics: Consultancy; Valent Technologies: Consultancy; LBC Pharmaceuticals: Consultancy; Amgen: Equity Ownership; BioMarin: Equity Ownership; Crown BioScience: Membership on an entity’s Board of Directors or advisory committees.

Ex Vivo Pharmacologic Modulation in a Nutrient-Rich Medium to Accelerate Engraftment of Human Umbilical Cord Blood

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 3807-3807
Author(s):  
Corey S Cutler ◽  
Daniel Shoemaker ◽  
Peter Westervelt ◽  
Daniel R. Couriel ◽  
Sumithra Vasu ◽  
...  
Keyword(s):  
Gene Expression ◽  
Umbilical Cord Blood ◽  
Ex Vivo ◽  
Phase 1 ◽  
Fold Increase ◽  
Phase 2 ◽  
Employment Equity ◽  
Phase 2 Trial ◽  
Equity Ownership ◽  
Neutrophil Engraftment

Abstract Umbilical cord blood (UCB) offers many potential advantages as a source of hematopoietic stem cells (HSCs) for allogeneic transplantation, including ease of collection, rapid availability, flexibility of HLA-matching, lower rates of GvHD and potentially lower relapse rates. However, the low HSC content of UCB compared to other graft sources results in a prolonged time to engraftment, and higher rates of graft failure and early mortality. Pulse ex vivo exposure of HSCs to 16,16-dimethyl PGE2 (FT1050) has been demonstrated to enhance HSC engraftment potential, which could benefit clinical UCB transplant. FT1050 modulation promotes multiple mechanisms, including increased proliferation, reduced apoptosis, and improved migration and homing [North 2007&2009; Hoggatt 2009]. Improved HSC homing is mediated by induction of CXCR4 gene expression leading to increased cell surface CXCR4. Further optimization of the UCB modulation process demonstrated that incubation with 10µM FT1050 for 2 hrs at 37C resulted in a maximal biological response of the FT1050-UCB (ProHema®). A Phase 1 trial was performed to evaluate the safety of FT1050-UCB paired with an unmanipulated UCB unit in reduced-intensity double UCBT (dUCBT) [Cutler 2013]. We observed durable, multi-lineage engraftment of FT1050-UCB with acceptable safety. Earlier neutrophil engraftment was observed relative to historical controls (median 17.5 vs. 21 days (historical control), p=0.045), coupled with preferential engraftment of the FT1050-UCB unit in 10 of 12 subjects. A Phase 2 multi-center clinical trial of FT1050-UCB in adult patients undergoing dUCBT for hematologic malignancies was then initiated. Subjects are randomized 2:1 to FT1050-UCB-containing vs. standard dUCBT after high-dose conditioning. The primary endpoint is a categorical analysis of neutrophil engraftment using a pre-specified control median. Data on the initial 11 subjects, of which 8 were randomized to receive FT1050-UCB, continue to demonstrate acceptable safety with adverse events attributed to FT1050-UCB limited primarily to common infusion-related side effects. Of the 8 FT1050-UCB subjects, 1 died prior to neutrophil engraftment, with the remaining 7 subjects engrafting at a median of 28 days vs. 31 days for the 3 control subjects. With median overall follow-up of 16.1 months, 4 of 8 subjects on the FT1050-UCB arm are alive with a median survival not reached (> 11.0 months). 1 of 3 control subjects is alive with median survival of 6.0 months. During the clinical translation process, the media used during FT1050 modulation of UCB was identified as a key variable. Standard UCB washing media, consisting of a nutrient-free saline solution of low molecular weight dextran and human serum albumin (LMD/HSA), is used clinically to stabilize fragile cells post-thaw by reducing lysis. This media was used in the Phase 1 trial and to initiate Phase 2. Early during the Phase 2 trial, we identified a novel cell-stabilizing nutrient-rich formulation (NRM), containing glucose, amino acids and other HSC-supporting nutrients that promoted full FT1050 modulation of UCB and increased cell viability. The expression of key FT1050-pathway genes was significantly higher with NRM compared to intermediate levels observed with LMD/HSA. Modulation of human CD34+ (hCD34+) cells with FT1050 in NRM led to an 8-fold increase over LMD/HSA in induced CXCR4 gene expression (20-fold total), which translated to significantly increased surface CXCR4 protein. In vivo homing models demonstrated that UCB CD34+ cells modulated with FT1050 in NRM resulted in a 2.2-fold homing increase relative to vehicle (p < 0.001) compared to a 1.6-fold increase with LMD/HSA (p = 0.002), with a significant difference between the two media conditions (p = 0.04). A xenotransplantation study in NSG mice with hCD34+ cells modulated with FT1050 in either NRM or LMD/HSA demonstrated a 2-fold increase in circulating hCD45+ cells 12-weeks post-transplant with NRM (p = 0.007; unpaired t-test). These findings supported the incorporation of NRM into the FT1050-UCB manufacturing process in order to further improve its clinical engraftment potential. Enrollment of a 60-patient Phase 2 trial has been initiated that incorporates this manufacturing change. Disclosures Shoemaker: Fate Therapeutics: Employment, Equity Ownership. Rezner:Fate Therapeutics: Employment. Guerrettaz:Fate Therapeutics: Employment. Robbins:Fate Therapeutics: Employment. Medcalf:Fate Therapeutics: Employment. Wolchko:Fate Therapeutics: Employment, Equity Ownership. Ferraro:Fate Therapeutics: Employment. Multani:Fate Therapeutics: Employment.

scholarly journals Ponatinib Efficacy and Safety in Patients with the T315I Mutation: Long-Term Follow-up of Phase 1 and Phase 2 (PACE) Trials

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 4552-4552 ◽  
Author(s):  
Michael J. Mauro ◽  
Jorge E. Cortes ◽  
Andreas Hochhaus ◽  
Michele Baccarani ◽  
Timothy P. Hughes ◽  
...  
Keyword(s):  
Research Funding ◽  
Progressive Disease ◽  
Phase 1 ◽  
Efficacy And Safety ◽  
Employment Equity ◽  
Long Term Follow Up ◽  
T315i Mutation ◽  
Equity Ownership

Abstract Background: Resistance to tyrosine kinase inhibitors (TKIs) in patients (pts) with chronic myeloid leukemia (CML) and Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL) is frequently caused by mutations in the BCR-ABL kinase domain. Ponatinib is the only approved oral TKI that inhibits the T315I mutant, which is uniformly resistant to other TKIs. Here we report long-term follow-up of the efficacy and safety of ponatinib in pts with the T315I mutation at baseline from the Phase 1 (Ph1) and PACE trials. Methods: The Ph1 trial (NCT01207440) evaluated safety and anti-leukemic activity of ponatinib (2-60 mg qd) in pts with CML or Ph+ ALL (N=81); the PACE trial (NCT00660920) evaluated efficacy and safety of ponatinib (45 mg qd) in CML and Ph+ ALL pts (N=449) resistant/intolerant to dasatinib or nilotinib or with the T315I mutation. Data reported are for pts with the T315I mutation at baseline, detected by Sanger sequencing at a central lab. Results: The Ph1 and PACE trials included 19 (29%) and 128 (29%) pts with the T315I mutation, respectively. Median age and median time since diagnosis were 47 and 2.7 years for Ph1, and 53 and 3.6 years for PACE.Pts were heavily pretreated: 89% in Ph1 and 84% in PACE had received ≥2 prior TKIs. As of Jan 6, 2014, median follow-up was 42 (1-59) months in Ph1, and 20 (0.1-40) months in PACE; 58% Ph1 (92% CP-CML) and 33% PACE (52% CP-CML) pts remained on study. Most-common reasons for discontinuation: administrative decision (16%) and progressive disease (16%) for Ph1, and progressive disease (31%) and adverse events (AEs; 13%) for PACE. Of the pooled chronic phase (CP)-CML pts, 75%, 72%, and 61% achieved MCyR, CCyR, and MMR, respectively, with deeper responses (MR4, MR4.5) observed in over a third of the pts (Table). MaHR was achieved in 58%, 27% and 38% of pooled AP-CML, BP-CML and Ph+ ALL pts, respectively. For Ph 1 CP-CML pts, 3-year CCyR duration estimates were 80%. For PACE CP-CML pts, 2-year MCyR/CCyR duration, PFS and OS estimates were 93%/79%, 72% and 82%, respectively. Only 1 CP-CML pt in PACE lost MCyR and 1 transformed to AP-CML. For AP-CML, BP-CML, and Ph+ ALL, estimated OS/PFS at 2 years was 69%/54%, 14%/10%, and 10%/N/A, respectively. The most frequent treatment-emergent AEs (TEAEs) observed in Ph1 CP-CML pts were dry skin (83%), rash (83%), arthralgia (75%), fatigue (75%), headache (67%), abdominal pain (58%), hypertension (58%), hypertriglyceridemia (58%), myalgia (58%), and nausea (58%). None of the 19 serious TEAEs that occurred in Ph1 CP-CML pts occurred in >1 pt. The most common (≥25%) TEAEs in PACE CP-CML pts were rash (48%), dry skin (42%), headache (41%), abdominal pain (39%), nausea (36%), constipation (33%), fatigue (33%), thrombocytopenia (28%), myalgia (28%), hypertension (27%), arthralgia (25%), and upper respiratory tract infection (25%). Most common (≥5 %) serious TEAEs in PACE CP-CML pts were acute myocardial infarction (8%), pancreatitis (8%), atrial fibrillation (6%), coronary artery disease (6%), congestive cardiac failure (5%), pneumonia (5%), cerebral infarction (5%), pyrexia (5%), increased lipase (5%), and dyspnea (5%). Arterial thrombotic events occurred in 1 (8%) Ph1, and 20 (31%) PACE pts. Venous thromboembolic events occurred in 1 (8%) Ph1, and 3 (5%) PACE pts. Despite the higher median dose intensity for T315I CP-CML pts (38 vs 30.8 mg/day overall CP-CML) in PACE, the safety profiles were similar. For CP-CML pts in PACE, responses achieved by 12 months were generally maintained after dose reduction primarily to manage AEs: 100% maintained MCyR; 100% maintained CCyR, and 79% maintained MMR. Conclusions: In Ph+ leukemia pts with the T315I mutation, where effective treatment options are limited, ponatinib continued to exhibit deep and durable responses with up to 6 years follow-up. Dose reductions to manage AEs did not impact maintenance of cytogenetic responses. The response rates and safety profile of T315I pts were comparable to, if not better than, those observed in the overall population of refractory CML and Ph+ ALL pts in ponatinib clinical trials. Table. Responses at Any Time in Ponatinib Treated Pts with T315I Mutation Phase 1 PACE Phase 1 and PACE Pooled n (%) n (%) n (%) CP-CML N=12 N=64 N=76 MCyR 11 (92) 46 (72) 57 (75) CCyR 10 (83) 45 (70) 55 (72) MMR 9 (75) 37 (58) 46 (61) MR4 7 (58) 25 (39) 32 (42) MR4.5 4 (33) 21 (33) 25 (33) AP-CML N=1 N=18 N=19 MaHR 0 11 (61) 11 (58) BP-CML N=2 N=24 N=26 MaHR 0 7 (29) 7 (27) Ph+ ALL N=4 N=22 N=26 MaHR 2 (50) 8 (36) 10 (38) Disclosures Mauro: ARIAD Pharmaceuticals, Inc.: Consultancy. Cortes:ARIAD, BMS, Novartis, Pfizer, Teva: Consultancy, Research Funding. Hochhaus:ARIAD Pharmaceuticals, Inc.: Research Funding. Baccarani:ARIAD, Novartis, BMS: Consultancy; ARIAD, Novartis, BMS, Pfizer, Teva: Honoraria; ARIAD, Novartis, BMS, Pfizer, Teva: Speakers Bureau. Hughes:Novartis, BMS, ARIAD: Honoraria, Research Funding. Guilhot:ARIAD Pharmaceuticals, Inc.: Honoraria. Deininger:BMS, Novartis, Celgene, Genzyme, Gilead: Research Funding; BMS, ARIAD, Novartis, Incyte, Pfizer: Advisory Board, Advisory Board Other; BMS, ARIAD, Novartis, Incyte, Pfizer: Consultancy. Kantarjian:ARIAD Pharmaceuticals, Inc., Pfizer, Amgen: Research Funding. Shah:ARIAD Pharmaceuticals, Inc., BMS: Research Funding. Flinn:ARIAD Pharmaceuticals, Inc.: Research Funding. Lustgarten:ARIAD Pharmaceuticals, Inc.: Employment, Equity Ownership. Rivera:ARIAD Pharmaceuticals, Inc.: Employment, Equity Ownership. Haluska:ARIAD Pharmaceuticals, Inc.: Employment, Equity Ownership. Clackson:ARIAD Pharmaceuticals, Inc.: Employment, Equity Ownership. Talpaz:ARIAD Pharmaceuticals, Inc., BMS, Sanofi, Incyte, Pfizer: Research Funding.

scholarly journals Resolution of Sickle Cell Disease Manifestations in Patients Treated with Lentiglobin Gene Therapy: Updated Results from the Phase 1/2 Hgb-206 Group C Study

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 990-990 ◽  
Author(s):  
Julie Kanter ◽  
John F. Tisdale ◽  
Markus Y. Mapara ◽  
Janet L. Kwiatkowski ◽  
Lakshmanan Krishnamurti ◽  
...  
Keyword(s):  
Gene Therapy ◽  
Research Funding ◽  
Phase 1 ◽  
Globin Gene ◽  
Post Treatment ◽  
Employment Equity ◽  
Advisory Committees ◽  
Cd34 Cells ◽  
Equity Ownership

Background β-globin gene transfer into hematopoietic stem cells (HSCs) could reduce or eliminate sickle cell disease (SCD)-related manifestations. LentiGlobin for SCD gene therapy contains autologous CD34+ cells transduced with the BB305 lentiviral vector (LVV), encoding a human β-globin gene with the anti-sickling T87Q mutation (βA-T87Q). The safety and efficacy of LentiGlobin for SCD is being evaluated in the ongoing Phase 1/2 HGB-206 Study (NCT02140554). The initial 7 patients (Group A) were treated with LentiGlobin made from bone marrow harvested HSCs. The protocol was modified to improve HbAT87Q production by including pre-harvest red blood cell (RBC) transfusions, increasing the total busulfan exposure, and using a refined LentiGlobin manufacturing process (Group B, n=2). An additional modification was made for Group C patients where HSC collection by plerixafor mobilization followed by apheresis was instituted. Data from these Group C patients are discussed here. Results from patients in Groups A and B are reported separately. Methods Patients (≥ 18 years) with severe SCD (including those with recurrent vaso-occlusive crisis [VOC] and acute chest syndrome [ACS]) were screened for eligibility. Patients received 240 µg/kg of plerixafor 4-6 hours prior to HSC collection via apheresis. CD34+ cells were transduced with BB305 LVV. Patients underwent myeloablative busulfan conditioning and subsequent LentiGlobin drug product (DP) infusion. Patients were monitored for adverse events (AEs), engraftment, vector copy number (VCN), total hemoglobin (Hb) and HbAT87Q expression, hemolysis markers, and SCD clinical manifestations. Data are presented as median (min-max). Results: As of 7 March 2019, 19 Group C patients, aged 26 (18-36) years, had initiated mobilization/apheresis and 13 patients were treated with LentiGlobin for SCD gene therapy. Median DP VCN, % transduced cells, and CD34+ cell dose in the 13 treated patients were: 3.8 (2.8-5.6) copies/diploid genome (c/dg), 80 (71-88) %, and 4.5 (3.0-8.0) x 106 CD34+ cells/kg, respectively. The median follow-up was 9.0 (1.0-15.2) months. Twelve patients achieved neutrophil and platelet engraftments at a median of 19 (15-24) days and 28 (19-136) days, respectively. As of the data cut-off, engraftment was not yet evaluable in 1 patient at 1-month post-infusion. All patients stopped red blood cell (RBC) transfusions within about 3 months post-LentiGlobin gene therapy. Median total hemoglobin (Hb) and Hb fractions in patients at various time points are shown in Figure 1. Median HbS levels were at or below 50% in all patients with at least 6 months follow-up. The median total Hb at last visit in 8 patients with at least 6 months of follow-up, was 11.5 (10.2-15.0) g/dL, with a corresponding HbAT87Q median contribution of 5.3 (4.5-8.8) g/dL and a median HbS 5.7 (4.8-8.0) g/dL. Of these 8 patients, 6 had a history of VOCs or ACS. The median annualized VOC+ACS rate in these patients was 5.3 (3-14) pre-treatment and decreased to 0 (0-2) post-treatment. One Grade 2 VOC was observed 3.5 months post-treatment. No ACS or serious VOCs were observed in Group C patients' post- treatment. Lactate dehydrogenase, reticulocyte count, and total bilirubin at last visit post-LentiGlobin infusion were 225.0 (130.0-337.0) U/L, 150.0 (42.1-283.0) 109/L, 22.2 (3.42-39.3) µmol/L, respectively, trending towards normalization. The most common non-hematologic Grade ≥ 3 AEs were febrile neutropenia (n=10) and stomatitis (n=7) post-DP infusion. Serious AEs were reported in 6 patients post-LentiGlobin treatment, most common being nausea and vomiting. To date, there have been no DP-related AEs or graft failure, vector-mediated replication competent lentivirus detected, or clonal dominance reported. Longer follow-up and additional patient data will be presented. Summary The safety profile of LentiGlobin gene therapy for SCD remains consistent with single-agent busulfan conditioning and underlying disease. Patients in HGB-206 Group C experienced high-level, sustained expression of gene-therapy derived hemoglobin, with median HbS levels reduced to ~50% and median total Hb levels of 11.5 g/dL at 6 months. The cessation of clinical complications (no ACS or serious VOCs) and decreased hemolysis suggest a strong therapeutic effect after LentiGlobin gene therapy in patients with SCD. Disclosures Kanter: Peerview: Honoraria; NHLBI: Membership on an entity's Board of Directors or advisory committees; Rockpointe: Honoraria; SCDAA: Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Honoraria; Imara: Consultancy; Jeffries: Consultancy; Modus: Consultancy; Guidepoint Global: Consultancy; GLG: Consultancy; Cowen: Consultancy; bluebird bio, Inc: Consultancy; Medscape: Honoraria; Sangamo: Consultancy. Kwiatkowski:Terumo: Research Funding; Novartis: Research Funding; Apopharma: Research Funding; Imara: Consultancy; Celgene: Consultancy; bluebird bio, Inc.: Consultancy, Research Funding; Agios: Consultancy. Schmidt:German Cancer Research Center, Heidelberg, Germany: Employment; GeneWerk GmbH, Heidelberg, Gemrany: Equity Ownership. Miller:bluebird bio, Inc.: Employment, Equity Ownership. Pierciey:bluebird bio, Inc.: Employment, Equity Ownership. Huang:bluebird bio, Inc.: Employment, Equity Ownership. Ribeil:bluebird bio, Inc.: Employment, Equity Ownership. Thompson:Baxalta: Research Funding; Novartis: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; bluebird bio, Inc.: Consultancy, Research Funding. Walters:AllCells, Inc: Consultancy; TruCode: Consultancy; Editas Medicine: Consultancy.

scholarly journals Mgta-456 Contains Large Numbers of Expanded Cord Blood (CB) CD34+CD90+ Hematopoietic Stem Cells (HSC) Which Confer All Engraftment Activity and Correlate with Accelerated Neutrophil Recovery after Myeloablative Conditioning in Patients with Hematologic Malignancy

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 2083-2083
Author(s):  
Anthony E. Boitano ◽  
Michael P. Cooke ◽  
Kevin A. Goncalves ◽  
Darin Sumstad ◽  
John E. Wagner
Keyword(s):  
Stem Cells ◽  
Research Funding ◽  
Cell Fraction ◽  
Cell Subpopulation ◽  
Employment Equity ◽  
Hematopoietic Stem ◽  
Neutrophil Recovery ◽  
Nsg Mice ◽  
Cd34 Cells ◽  
Equity Ownership

Abstract Background: Patient access to well-matched CB containing high doses of stem cells remains a challenge for successful transplants. Low numbers of CD34+ cells in CB has resulted in delayed neutrophil recovery and a risk of graft failure relative to other hematopoietic stem cell (HSC) sources. MGTA-456 is a cell therapy that consists of CD34+ cells expanded in a 15-day culture in the presence of an aryl hydrocarbon receptor antagonist (AHRa) and the CD34 depleted fraction obtained from the same CB unit. Thus far, 40 patients with hematological malignancy (n=36) and non-malignant diseases (n=4) have received MGTA-456 with a median follow-up of 2.5 years (range 0.1 to 5 years) and 75 days (20 to 143 days) respectively. All patients engrafted at a significantly faster rate as compared to similarly treated historical controls (p<0.01). The aim of the current study was to fully characterize the expanded CD34+ cell fraction of MGTA-456 phenotypically and functionally and identify the cell population that correlates with time to neutrophil recovery. We found that the expanded CD34+CD90+ population of MGTA-456 were the cells responsible for engraftment in NOD-scid IL2Rgammanull (NSG) mice. We hypothesized that the dose of CD34+CD90+ cells/kg would have the strongest correlation with time to neutrophil recovery. Methods: The expansion culture consisted of StemSpan SFEM supplemented with SCF, FLT- 3L, TPO and IL-6 (all at 50 ng/mL) and the AHRa without the addition of antibiotics. After a 10 or 15 day culture, the CD34 expanded product was characterized by cell surface markers (CD34, CD90, CD133, CD41, CD71, CD235a, CD3, CD4, CD8, CD14, CD15, CD16, CD11b, CD33, CD19, CD56, and CD10), as well as colony-forming unit (CFU) capacity and engraftment potential in NOD-scid IL2Rgammanull (NSG) mice in a subset of products. Results: The expanded CD34+ cell fraction of MGTA-456 consisted of CD34+CD133-CD90- cells (late progenitors), CD34+CD133+CD90- cells (early progenitors) and CD34+CD133+CD90+ (progenitors and stem cells) as shown in Figure 1. The CD34- cells within the expanded fraction contained erythroid (CD71+) and megakaryocyte progenitors (CD41+), CD33+, CD14+, CD15+, and CD11b+ myeloid cells and CD56+ cells. CD3+, CD8+, CD4+, CD16+, CD19+ as well as CD10+ cells were not present (<1%) in the CD34 expanded fraction of MGTA-456. To identify which of these cell populations contain the NSG engraftment activity, we sorted CD34-, CD34+CD90- and CD34+CD90+ cells from MGTA-456 and transplanted the cell fractions into NSG mice. These studies clearly demonstrated that all NSG engraftment activity resided in the CD34+CD90+ cell subpopulation (Figure 2). Based on this result, we correlated the dose of CD34-, CD34+CD90-, CD34+CD90+ cells, and CFU cells/kg infused with time to neutrophil recovery of patients treated with MGTA-456. The dose of TNC (r2=0.49, P<0.05), CD34+CD90- (r2=0.45, p<0.05), and CD34+CD90+ (r2=0.52, p<0.05) cells/kg all significantly correlated with time to neutrophil recovery. The dose of CD34+CD90+ cells/kg had the strongest correlation with time to neutrophil recovery consistent with the NSG engraftment result. Conclusion: In these studies, we demonstrate that the expanded CD34+ cell fraction of MGTA-456 contains large doses of CD34+CD90+ HSC and progenitors, which are critical for long term engraftment in NSG mice and correlated with rapid neutrophil recovery clinically. Disclosures Boitano: Magenta Therapeutics: Employment, Equity Ownership, Patents & Royalties. Cooke:Magenta Therapeutics: Employment, Equity Ownership, Patents & Royalties. Goncalves:Magenta Therapeutics: Employment, Equity Ownership, Patents & Royalties. Wagner:Magenta Therapeutics: Consultancy, Research Funding; Novartis: Research Funding.

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