Enhanced In Vivo Persistence and Proliferation of NK Cells Expanded in Culture with the Small Molecule Nicotinamide: Development of a Clinical-Applicable Method for NK Expansion

Abstract Adoptive transfer of cytolitic Natural Killer (NK) cells is a promising immunotherapeutic modality for hematologic and other malignancies. However, limited NK cell in vivo persistence and proliferation have been challenging clinical success of this therapeutic modality. Here we present a reliable, scalable and GMP-compliant culture method for the expansion of highly functional donor NK cells for clinical use. Nicotinamide (NAM), a form of vitamin B-3, serves as a precursor of nicotinamide adenine dinucleotide (NAD) and is a potent inhibitor of enzymes that require NAD including ADP ribosyltransferases and cyclic ADP ribose/NADase. As such, NAM is implicated in the regulation of cell adhesion, polarity, migration, proliferation, and differentiation. We have previously reported that NAM augments tumor cytotoxicity and cytokine (TNFα and IFN-γ) secretion of NK cells expanded in feeder-free culture conditions stimulated with IL-2 or IL-15. Immunophenotype studies demonstrated NK cells expanded with NAM underwent typical changes observed with cytokine only-induced NK cell activation with no significant differences in the expression of activating and inhibitory receptors. CD200R and PD-1 receptors were expressed at low levels in resting NK cells, but their expression was up-regulated following activation in typical cytokine expansion cultures. Interestingly, the increase in CD200R and PD-1 was reduced by NAM, suggesting these NK cells to be less susceptible to cancer immunoevasion mechanisms (Fig 1). In vivo retention and proliferation is a pre-requisite for the success of NK therapy. We have reported that NK expanded with NAM displayed substantially better retention in the bone marrow, spleen and peripheral blood of irradiated NSG mice. Using a carboxyfluorescein succinimidyl ester (CFSE) dilution assay, we demonstrated increased in vivo proliferation of NAM-cultured NK cells compared with cells cultured without NAM. These results were recently confirmed using a BrdU incorporation assay in irradiated NSG mice (Fig.2). These findings were mechanistically supported by a substantial increase in CD62L (L-selectin) expression in cultures treated with NAM. CD62L is pivotal for NK cell trafficking and homeostatic proliferation and its expression is down regulated in IL-2 or IL-15 stimulated cultures (Fig. 3). These data provided the foundation for the development of a feeder cell-free scalable culture method for clinical therapy using apheresis units obtained from healthy volunteers. CD3+ cells were depleted using a CliniMACS T cell depletion set. Following depletion, the CD3- fraction was analyzed for phenotypic markers and cultured in closed-system flasks (G-Rex100 MCS, Wilson Wolf) supplemented with 20ng/ml IL-15 or 50ng/ml IL-2 GMP, 10% human serum, minimum essential medium-α and NAM USP for two weeks. While at seeding, NK cells comprised 5-20% of total culture seeded cells, at harvest, NK cells comprised more than 97% of the culture. Although overall contamination of the NK cultures was low with either IL-15 or IL-2, a lower fraction of CD3+ and CD19+ cells was observed with IL-15 vs IL-2 (0.2±0.1% vs. 0.4±0.2% and 1.3±0.4% vs. 2.4±0.6%, respectively). Consequently, we decided to use IL-15 for clinical manufacturing. Optimization of NAM concentration studies showed similar expansion with 2.5 and 5 mM and a decrease in expansion with 7.5 mM NAM. Since NAM at 5 mM had a stronger impact on CD62L expression and on the release of IFNγ and TNFα than NAM at 2.5 mM, we selected 5mM NAM for clinical manufacturing. Overall median NK expansion after two weeks in closed G-Rex flasks supplemented with IL-15 and 5mM NAM was 50-fold (range 37-87). An additional and significant increase in expansion was obtained after doubling the culture medium one week post seeding. While there was a marked advantage for single culture feeding, more feedings had less impact on NK expansion and had a negative effect on the in vivo retention potential. Our optimized expansion protocol therefore involved one feeding during the two weeks expansion duration resulting in 162±30.7-fold expansion of NK cells relative to their input number in culture. Based on these data, we have initiated a clinical trial at University of Minnesota, to test the safety and efficacy of escalating doses (2 x 107/kg - 2 x 108/kg) of our novel NAM NK cell product in patients with refractory non-Hodgkins lymphoma and multiple myeloma (NCT03019666). Disclosures Peled: Gamida Cell: Employment, Equity Ownership. Brachya: Gamida Cell: Employment. Persi: Gamida Cell: Employment. Lador: gamida Cell: Employment, Equity Ownership. Olesinski: gamida cell: Employment. Landau: gamida cell: Employment, Equity Ownership. Galamidi: gamida cell: Employment. Peled: Biokine: Consultancy; Biosight: Consultancy. Miller: Celegene: Consultancy; Oxis Biotech: Consultancy; Fate Therapeutics: Consultancy, Research Funding. Bachanova: Oxis: Membership on an entity's Board of Directors or advisory committees, Research Funding; Zymogen: Consultancy, Membership on an entity's Board of Directors or advisory committees; Seattle-Genetics: Consultancy, Membership on an entity's Board of Directors or advisory committees; Novartis Pharmaceuticals Corporation: Membership on an entity's Board of Directors or advisory committees, Research Funding; Juno: Membership on an entity's Board of Directors or advisory committees.

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Preliminary Clinical Data from a Phase 1 Trial with CPI-818, a Selective ITK Inhibitor That Preferentially Blocks the Growth of T Lymphoma Cells

Blood ◽

10.1182/blood-2019-127338 ◽

2019 ◽

Vol 134 (Supplement_1) ◽

pp. 1571-1571

Author(s):

Patrick P. Ng ◽

Mehrdad Mobasher ◽

Kitman S. Yeung ◽

Andrew N. Hotson ◽

Craig M. Hill ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Nk Cells ◽

Board Of Directors ◽

Research Funding ◽

Nk Cell ◽

Phase 1 ◽

Employment Equity ◽

Advisory Committees ◽

Equity Ownership

Introduction ITK is a tyrosine kinase critical to T cell receptor (TCR) signaling. Overexpression of this gene has been reported in cutaneous T-cell lymphoma (CTCL) and peripheral T-cell lymphoma (PTCL). Genomic analyses have demonstrated the contribution of aberrant TCR signaling in the pathogenesis of T-cell lymphomas (TCL). RLK, a closely related kinase, is co-expressed with ITK in T and NK cells, and is partially functionally redundant with ITK signaling. In NK cells, ITK has been shown to be involved in FcγRIII signaling and antibody-dependent cellular cytotoxicity (ADCC). However, the relative contribution of ITK vs RLK in ADCC is not well understood. Thus, selective inhibition of ITK, but not other signal transduction components such as RLK, may be an effective strategy to treat TCL while preserving normal T and NK cell functions. CPI-818 is an orally bioavailable, covalent inhibitor of ITK with >100-fold selectivity over RLK and BTK. It was well tolerated and exhibited anti-tumor activity in companion dogs with spontaneous TCL (2019 AACR Annual Meeting Abstract #1313). A phase 1/1b trial with CPI-818 in human TCL has been initiated (NCT03952078). Here we present preclinical evidence that CPI-818 inhibits the proliferation of human malignant T cells with relative sparing of normal lymphocytes and report early results from the clinical trial. Methods Eligible patients for the dose-escalation/expansion trial of CPI-818 have relapsed/refractory TCL (PTCL, CTCL and others). Starting dose of CPI-818 is 100 mg BID continuously. The objectives of the study are to evaluate the safety and tolerability of CPI-818 in ascending dose levels; evaluate pharmacokinetics/pharmacodynamics and potential biomarkers. In in vitro studies, T cells from the blood of Sézary syndrome patients were stimulated for 6 days with αCD3/CD28. Sézary cells were identified by antibodies to specific TCR Vβ. For assays of ADCC, αCD20-coated lymphoma B cells were cultured with NK cells from multiple healthy donors for 18 h with inhibitors. In animal studies, mice received control or CPI-818-formulated diet (300 mg/kg/day). C57BL/6 mice were vaccinated with keyhole limpet hemocyanin (KLH) or subcutaneously implanted with the TCL line EL4. MRL/lpr mice began treatment at 9 weeks old. Lymph nodes were calipered weekly. Spleens and lungs were harvested at 22 weeks. Results Mouse models were studied to assess the impact of CPI-818 on normal, autoreactive and malignant T cells in vivo. No changes in total blood cell counts or T, B, NK cell subsets in lymphoid organs were seen in normal mice receiving daily doses of CPI-818 sufficient to continuously inhibit ITK for 28 days. Immune responses to antigen re-challenge were not affected in these mice, as determined by levels of antibody or CD4 T cell response to vaccination with KLH. In mice with established EL4 lymphoma, administration of CPI-818 reduced the growth of tumors at the primary site and in the draining lymph nodes (P values <0.033). CPI-818 also reduced lymphadenopathy and expansion of autoreactive T cells in the spleens of MRL/lpr mice (P values <0.0001), without affecting CD4 or CD8 cells. Sézary cells from 3 of 3 patients tested in vitro were more sensitive to growth inhibition with CPI-818 than autologous normal CD4 or CD8 cells, or T cells from a healthy donor (Figure 1). CPI-818 showed minimal inhibition of NK-mediated ADCC (5%), whereas CP-2193, an ITK/RLK dual inhibitor with an IC50 for ITK comparable to CPI-818, reduced ADCC by 50%. CPI-818 has been administered to two patients at the first dose level cohort (100 mg BID) with no DLTs, and with no changes to B, T, and NK cell counts in blood during the first dosing cycle (21 days). Pharmacokinetic and occupancy studies have revealed 80% and 50% occupancy of ITK at peak and trough drug levels, respectively in peripheral blood T cells. Conclusions CPI-818 is a selective covalent ITK inhibitor that has greater antiproliferative effects on malignant and autoreactive T cells compared to normal T cells. The drug has a minimal impact on NK mediated ADCC compared with a less selective inhibitor that also blocks RLK. Preliminary data from a phase 1/1b study shows CPI-818 at 100 mg BID was tolerable with acceptable bioavailability and ITK occupancy. Further dose escalation is ongoing. Disclosures Ng: Corvus Pharmaceuticals, Inc.: Employment, Equity Ownership. Mobasher:Corvus Pharmaceuticals: Employment, Equity Ownership. Yeung:Corvus Pharmaceuticals: Employment, Equity Ownership. Hotson:Corvus Pharmaceuticals: Employment, Equity Ownership. Hill:Corvus Pharmaceuticals: Employment, Equity Ownership. Madriaga:Corvus Pharmaceuticals: Employment, Equity Ownership. Dao-Pick:Corvus Pharmaceuticals: Employment, Equity Ownership. Verner:Corvus Pharmaceuticals: Employment, Equity Ownership. Radeski:Corvus Pharmaceuticals: Research Funding. Khodadoust:Corvus Pharmaceuticals: Research Funding. Kim:Innate Pharma: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Eisai: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Kyowa Hakko Kirin: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Merck: Research Funding; Horizon: Research Funding; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Seattle Genetics: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Galderma: Research Funding; Elorac: Research Funding; Soligenix: Research Funding; Medivir: Honoraria, Membership on an entity's Board of Directors or advisory committees; miRagen: Research Funding; Forty Seven Inc: Research Funding; Neumedicine: Research Funding; Portola Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Corvus: Honoraria, Membership on an entity's Board of Directors or advisory committees; Trillium: Research Funding. Miller:Corvus Pharmaceuticals: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees. Buggy:Corvus Pharmaceuticals: Employment, Equity Ownership. Janc:Corvus Pharmaceuticals: Employment, Equity Ownership.

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Stroma-Free Ex Vivo Expanded, CD34+ Cord Blood-Derived NK Cells Retain Lytic Activity After Long-Term Engraftment in NSGS Mice

Blood ◽

10.1182/blood.v120.21.580.580 ◽

2012 ◽

Vol 120 (21) ◽

pp. 580-580

Author(s):

Mark Wunderlich ◽

Mahesh Shrestha ◽

Lin Kang ◽

Eric Law ◽

Vladimir Jankovic ◽

...

Keyword(s):

Nk Cells ◽

Research Funding ◽

Nk Cell ◽

Ex Vivo ◽

Employment Equity ◽

Cell Product ◽

Equity Ownership ◽

Cellular Therapeutics

Abstract Abstract 580 Generating a large number of pure, functional immune cells that can be used in human patients has been a major challenge for NK cell-based immunotherapy. We have successfully established a cultivation method to generate human NK cells from CD34+ cells isolated from donor-matched cord blood and human placental derived stem cells, which were obtained from full-term human placenta. This cultivation method is feeder-free, based on progenitor expansion followed by NK differentiation supported by cytokines including thrombopoietin, stem cell factor, Flt3 ligand, IL-7, IL-15 and IL-2. A graded progression from CD34+ hematopoietic progenitor cells (HSC) to committed NK progenitor cells ultimately results in ∼90% CD3-CD56+ phenotype and is associated with an average 10,000-fold expansion achieved over 35 days. The resulting cells are CD16- and express low level of KIRs, indicating an immature NK cell phenotype, but show active in vitro cytotoxicity against a broad range of tumor cell line targets. The in vivo persistence, maturation and functional activity of HSC-derived NK cells was assessed in NSG mice engineered to express the human cytokines SCF, GM-CSF and IL-3 (NSGS mice). Human IL-2 or IL-15 was injected intraperitoneally three times per week to test the effect of cytokine supplementation on the in vivo transferred NK cells. The presence and detailed immunophenotype of NK cells was assessed in peripheral blood (PB), bone marrow (BM), spleen and liver samples at 7-day intervals up to 28 days post-transfer. Without cytokine supplementation, very few NK cells were detectable at any time-point. Administration of IL-2 resulted in a detectable but modest enhancement of human NK cell persistence. The effect of IL-15 supplementation was significantly greater, leading to the robust persistence of transferred NK cells in circulation, and likely specific homing and expansion in the liver of recipient mice. The discrete response to IL-15 versus IL-2, as well as the preferential accumulation in the liver have not been previously described following adoptive transfer of mature NK cells, and may be unique for the HSC-derived immature NK cell product. Following the in vivo transfer, a significant fraction of human CD56+ cells expressed CD16 and KIRs indicating full physiologic NK differentiation, which appears to be a unique potential of HSC-derived cells. Consistent with this, human CD56+ cells isolated ex vivo efficiently killed K562 targets in in vitro cytotoxicity assays. In contrast to PB, spleen and liver, BM contained a substantial portion of human cells that were CD56/CD16 double negative (DN) but positive for CD244 and CD117, indicating a residual progenitor function in the CD56- fraction of the CD34+ derived cell product. The BM engrafting population was higher in NK cultures at earlier stages of expansion, but was preserved in the day 35- cultured product. The frequency of these cells in the BM increased over time, and showed continued cycling based on in vivo BrdU labeling 28 days post-transfer, suggesting a significant progenitor potential in vivo. Interestingly, DN cells isolated from BM could be efficiently differentiated ex vivo to mature CD56+CD16+ NK cells with in vitro cytotoxic activity against K562. We speculate that under the optimal in vivo conditions these BM engrafting cells may provide a progenitor population to produce a mature NK cell pool in humans, and therefore could contribute to the therapeutic potential of the HSC-derived NK cell product. The in vivo activity of HSC-derived NK cells was further explored using a genetically engineered human AML xenograft model of minimal residual disease (MRD) and initial data indicates significant suppression of AML relapse in animals receiving NK cells following chemotherapy. Collectively, our data demonstrate the utility of humanized mice and in vivo xenograft models in characterizing the biodistribution, persistence, differentiation and functional assessment of human HSC-derived cell therapy products, and characterize the potential of HSC-derived NK cells to be developed as an effective off-the-shelf product for use in adoptive cell therapy approaches in AML. Disclosures: Wunderlich: Celgene Cellular Therapeutics: Research Funding. Shrestha:C: Research Funding. Kang:Celgene Cellular Therapeutics: Employment, Equity Ownership, Patents & Royalties. Law:Celgene Cellular Therapeutics: Employment, Equity Ownership, Patents & Royalties. Jankovic:Celgene Cellular Therapeutics: Employment, Equity Ownership, Patents & Royalties. Zhang:Celgene Cellular Therapeutics: Employment, Equity Ownership, Patents & Royalties. Herzberg:Celgene Cellular Therapeutics: Employment, Equity Ownership, Patents & Royalties. Abbot:Celgene Cellular Therapeutics: Employment, Equity Ownership, Patents & Royalties. Hariri:Celgene Cellular Therapeutics: Employment, Equity Ownership, Patents & Royalties. Mulloy:Celgene Cellular Therapeutics: Research Funding.

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Off-the-Shelf, Multiplexed-Engineered iPSC-Derived NK Cells Mediate Potent Multi-Antigen Targeting of B-Cell Malignancies with Reduced Cytotoxicity Against Healthy B Cells

Blood ◽

10.1182/blood-2021-148654 ◽

2021 ◽

Vol 138 (Supplement 1) ◽

pp. 407-407

Author(s):

Frank Cichocki ◽

Jode P Goodridge ◽

Ryan Bjordahl ◽

Svetlana Gaidarova ◽

Sajid Mahmood ◽

...

Keyword(s):

T Cells ◽

B Cells ◽

Nk Cells ◽

Board Of Directors ◽

Research Funding ◽

Nk Cell ◽

Advisory Committees ◽

Car T Cells ◽

Car T

Abstract Treatments for B-cell malignancies have improved over the past several decades with clinical application of the CD20-specific antibody rituximab and chimeric antigen receptor (CAR) T cells targeting CD19. Despite the success of these therapies, loss of CD20 after rituximab treatment has been reported in leukemia and lymphoma patients. Additionally, up to 50% of all patients receiving anti-CD19 CAR T-cell therapy relapse within the first year with many of those patients exhibiting CD19 loss. Thus, new therapeutic approaches are needed to address tumor antigen escape. Accordingly, we generated triple gene-modified iPSC-derived NK (iNK) cells, termed "iDuo" NK cells, tailored to facilitate multi-antigen targeting. The iPSC line was clonally engineered to express high-affinity, non-cleavable CD16a (hnCD16), an anti-CD19 CAR optimized for NK cell signaling, and a membrane-bound IL-15/IL-15R fusion (IL-15RF) molecule to enhance NK cell persistence (Fig. 1A). To model antigen escape, we generated CD19 knockout AHR77 lymphoma cells alongside wild type AHR77 cells (both CD20 +) as targets in cytotoxicity assays. Activated peripheral blood NK (PBNK) cells, non-transduced iNK cells, and iDuo NK cells were tested as effectors. Unlike PBNK cells or non-transduced iNK cells, iDuo NK cells efficiently eliminated wild type AHR77 cells with or without the addition of rituximab at all tested E:T ratios. Similarly, iDuo NK cells in combination with rituximab were uniquely able to efficiently eliminate CD19 KO AHR77 cells due to enhanced antibody-dependent cellular cytotoxicity (ADCC) driven by hnCD16 (Fig. 1B-E). Cytotoxicity mediated by iDuo NK cells was also evaluated using primary chronic lymphocytic leukemia (CLL) cells. Compared to expanded PBNK cells and non-transduced iNK cells, only iDuo NK cells (in the absence of rituximab) were able to kill primary CLL cells (Fig. 1F). Expression of IL-15RF by iDuo NK cells uniquely supports in vitro expansion without the need for cytokine supplementation. To determine whether IL-15RF supports in vivo persistence of iDuo NK cells, CD19 CAR iNK cells (lacking IL-15RF) and iDuo NK cells were injected into NSG mice without the addition of cytokines or CD19 antigen availability. iDuo NK cell numbers peaked within a week after injection and persisted at measurable levels for ~5 weeks, in marked contrast to CD19 CAR iNK cell numbers that were undetectable throughout (Fig. 1G). To evaluate the in vivo function of iDuo NK cells, NALM6 leukemia cells were engrafted into NSG mice. Groups of mice received tumor alone or were treated with 3 doses of thawed iDuo NK cells. iDuo NK cells alone were highly effective in this model as evidenced by complete survival of mice in the treatment group (Fig. 1H). To assess iDuo NK cells in a more aggressive model, Raji lymphoma cells were engrafted, and groups of mice received rituximab alone, iDuo NK cells alone, or iDuo NK cells plus rituximab. Mice given the combination of iDuo NK cells and rituximab provided extended survival compared to all other arms in the aggressive disseminated Raji lymphoma xenograft model (Fig. 1I). One disadvantage of anti-CD19 CAR T cells is their inability to discriminate between healthy and malignant B cells. Because NK cells express inhibitory receptors that enable "self" versus "non-self" discrimination, we reasoned that iDuo NK cells could have higher cytotoxicity against tumor cells relative to healthy B cells. To address this, we labeled Raji cells, CD19 + B cells from healthy donor peripheral blood mononuclear cells (PBMCs) and CD19 - PBMCs. Labeled populations of cells were co-cultured with iDuo NK cells, and specific killing was analyzed. As expected, iDuo NK cells did not target CD19 - PBMCs. Intriguingly, iDuo NK cells had much higher cytotoxic activity against Raji cells compared to primary CD19 + B cells, suggesting a preferential targeting of malignant B cells compared to healthy B cells. Together, these results demonstrate the potent multi-antigen targeting capability and in vivo antitumor function of iDuo NK cells. Further, these data suggest that iDuo NK cells may have an additional advantage over anti-CD19 CAR T cells by discriminating between healthy and malignant B cells. The first iDuo NK cell, FT596, is currently being tested in a Phase I clinical trial (NCT04245722) for the treatment of B-cell lymphoma. Figure 1 Figure 1. Disclosures Cichocki: Gamida Cell: Research Funding; Fate Therapeutics, Inc: Patents & Royalties, Research Funding. Bjordahl: Fate Therapeutics: Current Employment. Gaidarova: Fate Therapeutics, Inc: Current Employment. Abujarour: Fate Therapeutics, Inc.: Current Employment. Rogers: Fate Therapeutics, Inc: Current Employment. Huffman: Fate Therapeutics, Inc: Current Employment. Lee: Fate Therapeutics, Inc: Current Employment. Szabo: Fate Therapeutics, Inc: Current Employment. Wong: BMS: Current equity holder in publicly-traded company; Fate Therapeutics, Inc: Current Employment. Cooley: Fate Therapeutics, Inc: Current Employment. Valamehr: Fate Therapeutics, Inc.: Current Employment. Miller: Magenta: Membership on an entity's Board of Directors or advisory committees; ONK Therapeutics: Honoraria, Membership on an entity's Board of Directors or advisory committees; Vycellix: Consultancy; GT Biopharma: Consultancy, Patents & Royalties, Research Funding; Fate Therapeutics, Inc: Consultancy, Patents & Royalties, Research Funding; Sanofi: Membership on an entity's Board of Directors or advisory committees; Wugen: Membership on an entity's Board of Directors or advisory committees.

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Results of a Phase 1 Trial of Gda-201, Nicotinamide-Expanded Allogeneic Natural Killer (NK) Cells in Patients with Refractory Non-Hodgkin Lymphoma (NHL) and Multiple Myeloma

Blood ◽

10.1182/blood-2020-142419 ◽

2020 ◽

Vol 136 (Supplement 1) ◽

pp. 6-6 ◽

Cited By ~ 1

Author(s):

Veronika Bachanova ◽

Joseph Maakaron ◽

David H. McKenna ◽

Qing Cao ◽

Todd E. DeFor ◽

...

Keyword(s):

Nk Cells ◽

Board Of Directors ◽

Research Funding ◽

Nk Cell ◽

Phase 1 ◽

Advisory Committees ◽

Non Hodgkin Lymphoma ◽

Cell Manufacturing ◽

Cell Current

Background: The innate capacity of natural killer (NK) cells to kill tumor targets has been translated into cancer immunotherapy. GDA-201 is a novel allogeneic NK cell product derived from NK cells from healthy donors, expanded ex-vivo with nicotinamide (NAM) and IL-15. We previously reported improved killing function, in vivo proliferation, organ trafficking, and augmented resistance against exhaustion in pre-clinical models. We conducted a phase 1 study of GDA-201 in combination with monoclonal antibodies to enhance NK cell targeting through antibody-dependent cellular cytotoxicity (ADCC). We now report safety data in patients (pts) with relapsed or refractory (R/R) non-Hodgkin lymphoma (NHL) and multiple myeloma (MM), and report efficacy outcomes in pts with NHL. Methods: Following donor apheresis, CD3-depleted mononuclear cells were cultured for 14-16 days with NAM (5mM) and IL-15 (20ng/ml), resulting in a 40-fold increase in NK cells and increased expression of CD62L from 2.9% to 21%. GDA-201 contained ~98% NK cells, and CD3 content was maintained at <0.5% (<5x105/kg/dose). Pts with R/R B-cell NHL or MM received lymphodepleting (LD) therapy with cyclophosphamide (400mg/m2 IV x 3d) and fludarabine (30 mg/m2 /d IV x 3d), followed by GDA-201 (days 0 and 2) and low-dose IL-2 (6 million units sc x 3 doses). Pts with NHL or MM received rituximab (375 mg/m2) or elotuzumab (10 mg/kg), respectively, x 3 weekly infusions. Results: 30 pts were enrolled:15 with NHL and 15 with MM, in 3 cohorts of escalating GDA-201 dose; 15 pts received the maximum target dose (median dose 12.4 [range 2.0-26.0] x 107 cells/kg). There were no dose limiting toxicities. The most common grade 3/4 adverse events were thrombocytopenia (n=9), hypertension (n=5), neutropenia (n=4), febrile neutropenia (n=4), and anemia (n=3). There were no neurotoxic events, confirmed cytokine release syndrome, graft versus host disease, or marrow aplasia. One patient died of E-coli sepsis. In pts with NHL, histologies included diffuse large B cell lymphoma (DLBCL) (de novo n=5, transformed n=3), follicular lymphoma (FL) (n=6), and mantle cell lymphoma (n=1). Median age was 64 (range 48-83 years). Pts had a median of 3 lines of prior therapy (range 1-8); most were multiply relapsed or refractory (n=2), and 87% had advanced stage. Median follow-up was 10.8 months (range 4.3-27.5 months). Ten pts had complete response (CR): 6/6 pts with FL and 4/8 with DLBCL; 1 pt had partial response (PR), and overall response rate in pts with NHL was 73.3%. Median duration of response was 8.7 months (range 4.3-25 months). Flow cytometry confirmed the persistence of GDA-201 in peripheral blood for 7-10 days (range 2-92% donor NK cells on day 7), as well as enhanced in vivo proliferation (median Ki 67 99%). Flow cytometry of biopsied tissues at day 4 demonstrated trafficking to bone marrow and lymph nodes. Four pts underwent re-treatment with GDA-201 without LD chemotherapy; GDA-201 cells were detectable in blood after the re-treatment and likely contributed to deepening of response in 2 patients. Post-GDA-201 therapy included allogeneic (n=2) and autologous (n=1) hematopoietic stem cell transplantation. One-year estimates of progression-free survival and overall survival were 66% (95% CI 36-84%) and 82% (95% CI 42-95%), respectively. Conclusions: Cellular therapy using GDA-201 with monoclonal antibodies to enhance ADCC was well-tolerated, and demonstrated significant clinical activity in heavily pretreated pts with advanced NHL. Data support the future testing of multiple infusions to potentially enhance anti-tumor effect. The omission of lymphodepleting chemotherapy is feasible and contributes to safety of this approach. Phase II studies in aggressive and indolent NHL cohorts are planned. Disclosures Bachanova: Incyte: Research Funding; FATE: Research Funding; Kite: Membership on an entity's Board of Directors or advisory committees; Karyopharma: Membership on an entity's Board of Directors or advisory committees; BMS: Research Funding; Gamida Cell: Membership on an entity's Board of Directors or advisory committees, Research Funding. McKenna:Gamida: Other: Cell Manufacturing; Fate Therapeutics: Other: Cell Manufacturing; Intima: Other: Cell Manufacturing; Magenta: Other: Cell Manufacturing. Janakiram:Takeda, Fate, Nektar: Research Funding. Simantov:Gamida Cell: Current Employment. Lodie:Gamida Cell: Current Employment. Miller:Vycellix: Consultancy; Nektar: Honoraria, Membership on an entity's Board of Directors or advisory committees; Onkimmune: Honoraria, Membership on an entity's Board of Directors or advisory committees; GT Biopharma: Consultancy, Patents & Royalties, Research Funding; Fate Therapeutics, Inc: Consultancy, Patents & Royalties, Research Funding.

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Antibody-Interferon-Alpha Fusion Protein Therapy for the Treatment of B-Cell Non-Hodgkin Lymphoma: Enhanced ADCC, Inhibition of Proliferation, and In Vivo Eradication of CD20+ Human Lymphomas

Blood ◽

10.1182/blood.v126.23.2762.2762 ◽

2015 ◽

Vol 126 (23) ◽

pp. 2762-2762 ◽

Cited By ~ 1

Author(s):

John M. Timmerman ◽

Kristopher K Steward ◽

Reiko E Yamada ◽

Patricia A Young ◽

Dena M. Minning ◽

...

Keyword(s):

Fusion Protein ◽

B Cell ◽

Board Of Directors ◽

Research Funding ◽

Employment Equity ◽

Advisory Committees ◽

Term Survival ◽

Equity Ownership

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.

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Immune Profiling of Relapsed or Refractory Multiple Myeloma Patients Treated with Pomalidomide and Low-Dose Dexamethasone in Combination with Daratumumab

Blood ◽

10.1182/blood-2018-99-111554 ◽

2018 ◽

Vol 132 (Supplement 1) ◽

pp. 2012-2012 ◽

Cited By ~ 2

Author(s):

William E. Pierceall ◽

Nizar Bahlis ◽

David S Siegel ◽

Gary J. Schiller ◽

Christy J. Samaras ◽

...

Keyword(s):

Multiple Myeloma ◽

T Cells ◽

T Cell ◽

Nk Cells ◽

Board Of Directors ◽

Research Funding ◽

Employment Equity ◽

Advisory Committees ◽

Ki 67 ◽

Equity Ownership

Abstract Background: Multiple myeloma clinical trial CC-4047-MM-014 (NCT01946477) is a Phase II study designed to test the safety and efficacy of pomalidomide and low-dose dexamethasone alone (arm A) or in combination with daratumumab, an anti-CD38 antibody, (arm B) subjects with relapsed or refractory multiple myeloma who have received a first or second line treatment of lenalidomide-based therapy. Immunomodulatory agents (IMiD® compounds) continue to be the backbone of multiple myeloma therapy especially when combined with monoclonal antibodies, more specifically pomalidomide had been shown previously to enhance T cell- and NK cell-mediated immunity. We sought to characterize on-treatment pharmacodynamic changes of immune biomarkers associated with POM + LoDEX + DARA administration (arm B) using multicolor flow cytometry panels designed to characterize T-cell subsets and CD38+ expressing cells. IMiD agents are the backbone of combination regimens in the treatment of patients with newly diagnosed or relapsed and/or refractory multiple myeloma. The anti-myeloma properties of these agents derive from a dual mechanism of pro-apoptotic effects on tumor cells as well as enhanced immune stimulation. An understanding of how IMiD agents interact with new monoclonal antibodies to modify patient immune profiles offers key insights into the role of such in innate and adaptive immunity in determining patient outcomes. Methods and Results: Peripheral blood samples were collected at screening, Cycle1 Days 1, 8, and 15, and Cycle 2 Days 1 and 15 to monitor pharmacodynamic changes in populations of T cells, NK cells, monocytes and MDSCs by flow cytometry. From 112 patients enrolled in Arm B, 98 patients had baseline and post-treatment specimens available for these analyses. As expected, combination treatment with POM + LoDEX + DARA led to decreased peripheral counts of CD56+CD16+ NK cells as well as CD4+CD38+ and CD8+CD38+ T cell subpopulations. Decreased counts were also noted in CD3-CD19+ B cells. In contrast, total counts of CD14+ monocytes and CD3+CD4+ or CD3+CD8+ T cells were stably maintained and pronounced increases were observed in proliferating CD4+Ki-67+ and CD8+Ki-67+ T cells. Further, when examined as a percent of total counts, increases were observed in CD14+ monocytes, CD3+CD4+ and CD3+CD8+ T-cells, with decreases in CD3-CD19+ B-cells and CD3-CD56+CD16+ NK cells. Correlation of these pharmacodynamic changes with clinical outcomes will be presented. In addition, baseline immune profiling of specific cell population subsets and associations with best overall response and progression-free survival is currently being analyzed. Conclusions: The triplet regimen POM + LoDEX + DARA has shown notable clinical activity with deep and durable responses in relapsed multiple myeloma patients progressed and are or refractory to lenalidomide. Immune characterization here is consistent with a model for clinical activity in which the loss of CD56+CD16+ NK cells along with a concomitant immune suppression by loss of CD38+CD4+ and CD38+CD8+ T- cells is offset by an increase in proliferating cytotoxic CD4+Ki-67+ and CD8+Ki-67+ T-cell populations. Our results demonstrate that patients treated with the POM + LoDEX + DARA combination do not demonstrate impairment in the innate and adaptive immune compartments and, in contrast, show significant proliferative activity in the subsets of CD4, CD8 and NK cells following treatment. Pomalidomide had been shown previously to enhance T cell- and NK cell-mediated immunity; these data are consistent with a mechanism of action in which pomalidomide administration facilitates the ability to overcome immunosuppressive effects of Dara and LoDex. Potential associations of immune biomarkers with patient outcomes is ongoing and will be updated. Disclosures Pierceall: Celgene Corporation: Employment, Equity Ownership. Bahlis:Janssen: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Amgen: Consultancy, Honoraria, Research Funding. Siegel:Merck: Consultancy, Honoraria, Speakers Bureau; Celgene: Consultancy, Honoraria, Research Funding, Speakers Bureau; Karyopharm: Consultancy, Honoraria; Amgen: Consultancy, Honoraria, Speakers Bureau; BMS: Consultancy, Honoraria, Speakers Bureau; Novartis: Honoraria, Speakers Bureau; Janssen: Consultancy, Honoraria, Speakers Bureau; Takeda: Consultancy, Honoraria, Speakers Bureau. Schiller:Astellas Pharma: Membership on an entity's Board of Directors or advisory committees, Research Funding; bluebird bio: Research Funding. Sebag:Amgen Canada: Membership on an entity's Board of Directors or advisory committees; Takeda Canada: Membership on an entity's Board of Directors or advisory committees; Janssen Inc.: Membership on an entity's Board of Directors or advisory committees; Celgene Canada: Membership on an entity's Board of Directors or advisory committees. Berdeja:Takeda: Research Funding; Genentech: Research Funding; Sanofi: Research Funding; Bristol-Myers Squibb: Research Funding; Celgene: Research Funding; Janssen: Research Funding; Glenmark: Research Funding; Amgen: Research Funding; Novartis: Research Funding; Poseida Therapeutics, Inc.: Research Funding; Bluebird: Research Funding; Teva: Research Funding. Ganguly:Amgen: Consultancy; Daiichi Sankyo: Research Funding; Janssen: Consultancy; Seattle Genetics: Speakers Bureau. Matous:Celgene: Consultancy, Honoraria, Speakers Bureau. Srinivas:VAHCSNJ: Employment. Bar:Celgene: Consultancy. Quick:CTI BioPharma: Research Funding. Fonseca:Celgene: Speakers Bureau. Reece:Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Honoraria, Research Funding; Takeda: Consultancy, Honoraria, Research Funding; Merck: Honoraria, Research Funding; Otsuka: Research Funding. Serbina:Celgene: Employment. Zafar:Celgene: Employment. Agarwal:Celgene Corporation: Employment, Equity Ownership. Thakurta:Celgene Corporation: Employment, Equity Ownership.

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Transient Inhibition of Transforming Growth Factor-β1 in Human Blood-Derived CD34+ Cells Enhances Survival and Proliferation in Vitro and Vascular Reparative functions In Vivo.

Blood ◽

10.1182/blood.v114.22.3546.3546 ◽

2009 ◽

Vol 114 (22) ◽

pp. 3546-3546

Author(s):

Stephen Bartelmez ◽

Ashay Bhatwadekar ◽

Patrick Iversen ◽

Francis W Ruscetti ◽

Maria Grant

Keyword(s):

Board Of Directors ◽

Research Funding ◽

Ex Vivo ◽

Cxcr4 Expression ◽

Employment Equity ◽

Advisory Committees ◽

Cd34 Cells ◽

Equity Ownership ◽

Tgf Β1

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.

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ACY-241, a Novel, HDAC6 Selective Inhibitor: Synergy with Immunomodulatory (IMiD®) Drugs in Multiple Myeloma (MM) Cells and Early Clinical Results (ACE-MM-200 Study)

Blood ◽

10.1182/blood.v126.23.3040.3040 ◽

2015 ◽

Vol 126 (23) ◽

pp. 3040-3040 ◽

Cited By ~ 8

Author(s):

Ruben Niesvizky ◽

Paul G. Richardson ◽

Nashat Y. Gabrail ◽

Sumit Madan ◽

Andrew J. Yee ◽

...

Keyword(s):

Clinical Trial ◽

Combination Therapy ◽

Board Of Directors ◽

Research Funding ◽

Selective Inhibitor ◽

Employment Equity ◽

Advisory Committees ◽

Equity Ownership

Abstract Histone deacetylase (HDAC) enzymes are attractive therapeutic targets in oncology, but non-selective HDAC inhibitors have led to dose-limiting toxicities in patients, particularly in combination with other therapeutic agents. Ricolinostat (ACY-1215), a first-in-class orally available HDAC inhibitor that is 11-fold selective for HDAC6, synergizes in vitro and in vivo in models of MM and lymphoma with bortezomib (Santo, Blood, 2012; Amengual, Clin Cancer Res, 2015) or carfilzomib (Mishima, Br J Haematol, 2015; Dasmahapatra, Mol Cancer Ther, 2014). Furthermore, ricolinostat has demonstrated an excellent safety and tolerability profile in phase I trials as an oral liquid formulation (Raje, Haematologica, 2014, Suppl 1). We have now identified ACY-241 as a structurally related and orally available selective inhibitor of HDAC6 that is undergoing clinical evaluation in tablet form. In combination with ricolinostat, the immunomodulatory (IMiD®) class of drugs, including lenalidomide (Len) and pomalidomide (Pom), exhibit striking anti-myeloma properties in a variety of MM models (Quayle, AACR, 2014) and have demonstrated clinical activity in MM patients (Yee, ASH, 2014). In support of our ongoing development of ACY-241, we show here that combination with either Len or Pom leads to synergistic decrease in MM cell viability in vitro. Time course studies demonstrated cell cycle arrest followed by progressive induction of apoptosis after prolonged exposure to Len or Pom. Notably, the addition of ACY-241 to either Len or Pom resulted in synergistic increases in apoptosis of MM cells. At the molecular level, treatment with IMiDs reduced expression of the critical transcription factors MYC and IRF4, which was further reduced by combination treatment with ACY-241. Current studies are exploring the molecular mechanism underlying this effect, which may be a consequence of low level inhibition of HDAC1, 2, and 3 by ACY-241. Prolonged treatment with ACY-241 plus Pom was well tolerated in vivo with no evidence of toxicity, and the combination resulted in a significant extension of survival in a xenograft model of MM. Given the comparable tolerability profiles of ricolinostat and ACY-241 and the similar preclinical activity in combination with IMiDs, a clinical trial (NCT02400242) is currently evaluating ACY-241 in combination with Pom and low-dose dexamethasone in MM patients. Predicated upon the clinical experience with ricolinostat and the non-clinical pharmacokinetics of ACY-241, we designed an expedited first-in-human phase 1a/1b clinical trial of a single cycle of ACY-241 monotherapy followed by ACY-241 in combination with Pom and dexamethasone in MM patients. A merged monotherapy/combination trial design was chosen to grant patients access to combination therapy with an established regimen while enabling insight into the safety, pharmacokinetics, and pharmacodynamics of ACY-241 monotherapy. Patients with relapsed or relapsed-and-refractory MM previously treated with at least two cycles of Len and a proteasome inhibitor were eligible for this trial. The first patient was enrolled in June 2015. This patient tolerated monotherapy well and pharmacokinetics showed maximal plasma levels of ACY-241 in the micromolar range, consistent with predictions. An update on enrollment, pharmacokinetic and pharmacodynamic profiles as well as safety of monotherapy and combination therapy will be provided. Disclosures Niesvizky: Celgene: Consultancy, Speakers Bureau. Richardson:Jazz Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees; Millennium Takeda: Membership on an entity's Board of Directors or advisory committees; Gentium S.p.A.: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene Corporation: Membership on an entity's Board of Directors or advisory committees. Gabrail:Onyx: Honoraria, Speakers Bureau; BI: Honoraria, Speakers Bureau; Janssen: Speakers Bureau; Sanofi: Honoraria, Speakers Bureau. Madan:Onyx: Speakers Bureau; Celgene: Speakers Bureau. Quayle:Acetylon Pharmaceuticals, Inc.: Employment, Equity Ownership. Almeciga-Pinto:Acetylon Pharmaceuticals, Inc: Employment. Jones:Acetylon Pharmaceuticals, Inc.: Employment, Equity Ownership. Houston:Acetylon Pharmaceuticals, Inc: Employment. Hayes:Acetylon Pharmaceuticals, Inc: Employment. Van Duzer:Acetylon Pharmaceuticals, Inc: Employment. Wheeler:Acetylon Pharmaceuticals, INC: Employment. Trede:Acetylon Pharmaceuticals, Inc: Employment. Raje:Acetylon: Research Funding; Celgene Corporation: Consultancy; BMS: Consultancy; Amgen: Consultancy; Millenium: Consultancy; AstraZeneca: Research Funding; Novartis: Consultancy; Onyx: Consultancy; Eli Lilly: Research Funding; Takeda: Consultancy.

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Targeting Autophagy Kinase ULK1 Can Reverse Bcl2 Inhibitor (ABT-199) Induced Autophagy to Overcome Acquired Resistance in Acute Myeloid Leukemia

Blood ◽

10.1182/blood-2018-99-114817 ◽

2018 ◽

Vol 132 (Supplement 1) ◽

pp. 3934-3934

Author(s):

Seemana Bhattacharya ◽

Sujan Piya ◽

Qi Zhang ◽

Natalia Baran ◽

Teresa McQueen ◽

...

Keyword(s):

Board Of Directors ◽

Myeloid Leukemia ◽

Research Funding ◽

Acquired Resistance ◽

Advisory Committees ◽

Qrt Pcr ◽

Nsg Mice ◽

Equity Ownership ◽

Acute Myeloid

Abstract Introduction Anti-apoptotic Bcl2 family members mediate resistance to therapies in acute myeloid leukemia (AML)1. The small molecule Bcl2 inhibitor ABT-199 (venetoclax) promotes mitochondria driven intrinsic apoptosis, and in combination with hypomethylating agents or chemotherapy, has been highly promising in the clinic as treatment of AML2-4. The response rate to ABT-199 is very impressive, but acquired resistance is a major problem. Compensatory upregulation of Mcl1 is an important mechanism of such acquired resistance to mitochondrial apoptosis5. Autophagy is vital for mitochondrial health, mediates resistance to apoptosis and is induced by Bcl2 inhibition6. We performed mechanistic studies to address our hypothesis that disabling autophagy by targeting the apical autophagy kinase ULK1 can reverse resistance to ABT-199. Methods ULK1 was genetically modified in OCIAML3 (human AML cell line), by shRNA knockdown (KD) or CRISPR-Cas9 knockout (KO). In addition, AML cell lines (including ABT-199 resistant) and patient samples were treated with ABT-199 and ULK1 inhibitor SBI-02069657. Combination index (CI) for drug synergy was calculated based on Chou-Talalay method8. Drug-treated or genetically manipulated cells were profiled by reverse phase protein array (RPPA), mass cytometry (CyTOF) and gene expression profiling (GEP). Autophagy was detected by LC3 quantification by western blot (WB) and flow cytometry, and monodansylcadaverine assay. Mitochondrial functions were analyzed by Seahorse Cell Mito Stress test, and MTG, TMRE and ROS assays (flow cytometry). For in vivo studies ULK1 KO and corresponding control cells were injected in NSG mice and monitored by bioluminescent imaging (BLI) and quantification of human CD45 cells. Results ABT-199 induced autophagy in OCIAML3 (increase by 175±27%, p=0.01 - LC3 flow; 4X increase in LC3 II/I ratio - WB). Apoptosis induction by ABT-199 was enhanced by ULK1 KD (36±1.9% over control, p<0.01) or KO (77±1.3%, p<0.01). ULK1 inhibitor SBI-0206965 demonstrated high synergy with ABT-199 at inducing apoptosis in OCIAML3 (CI = 0.51, p<0.001) and MOLM13 (CI = 0.24, p<0.001). The combination was also effective in eliminating bulk and CD34+ stem/progenitor cells in primary AML samples (CI - Bulk: 0.69; CD34: 0.74; p<0.05) (Fig 1). Mcl1 was significantly downregulated by ULK1 inhibitor alone and in combination with ABT-199. ULK1 inhibition lowered Mcl1 transcription, as measured by qRT-PCR: 43±0.03% with SBI-0206965 and 63±0.3% in KO cells (both p<0.01). SBI-0206965 inhibited Mcl1 transcription regulators Stat3 and Erk1/2 and enhanced DNA damage in combination with ABT-199 (WB) (Fig 2). Since ABT-199 modulates mitochondrial function, we examined the effect of inhibiting ULK1 in this context. By Seahorse assay, the combination decreased basal OCR and ATP production by 62 and 58% respectively, p<0.01. This was accompanied by an increase in membrane depolarization (TMRE change - OCIAML3: 62%, MOLM13: 82%; p<0.01) and mitochondrial ROS generation (62% increase, p=0.01) compared to control cells (Fig 3). Interestingly, ULK1 inhibition increased mitochondrial mass (30%, p=0.012) by MTG assay, which may be due to impaired mitophagy. Thus, the combination impairs mitochondrial metabolism and function, which results in the observed increase in ROS that may account for the observed DNA damage and apoptosis. CD44/44v is critical for mitigating ROS through reduced glutathione (GSH)9, and ULK1 inhibition lowered CD44/44v transcription (qRT-PCR) and intracellular GSH in AML cells. Corroborating our earlier data, the ABT-199 resistant cells (OCIAML2R & MOLM13R) show enhanced autophagy as compared to parental cells (OCIAML2: 83%, MOLM13: 35% increase; p=0.001 & 0.009). SBI-0206965 reversed ABT-199 induced autophagy and restored ABT-199 sensitivity in these cells (Fig 4). In a pilot in vivo experiment control and ULK1 KO cells were injected in NSG mice and leukemia engraftment was markedly delayed in the ULK1 KO group (Fig 5). The therapeutic combination study is ongoing. Conclusion Results indicate concomitant targeting of autophagy by ULK1 inhibition and Bcl2 inhibition by ABT-199 can overcome acquired resistance to ABT-199. Hence, with the emergence of Bcl2 inhibitors in frontline therapy for AML and efforts at developing ULK1 inhibitors, this study informs the development of novel apoptosis/autophagy targeting approaches to improve AML therapy. Disclosures Konopleva: Stemline Therapeutics: Research Funding; abbvie: Research Funding; Immunogen: Research Funding; cellectis: Research Funding. Andreeff:Daiichi-Sankyo: Consultancy, Patents & Royalties: MDM2 inhibitor activity patent, Research Funding; United Therapeutics: Patents & Royalties: GD2 inhibition in breast cancer ; Aptose: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy, Research Funding; Jazz Pharma: Consultancy; SentiBio: Equity Ownership; Oncolyze: Equity Ownership; Celgene: Consultancy; Reata: Equity Ownership; Oncoceutics: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Eutropics: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Astra Zeneca: Research Funding.

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Efficient Scale-up and Pre-Clinical Evaluation of NKG2C+ Adaptive NK Cell Expansion for Therapy Against High-Risk AML/MDS

Blood ◽

10.1182/blood-2018-195 ◽

2018 ◽

Vol 132 (Supplement 1) ◽

pp. 195-195

Author(s):

Ebba Sohlberg ◽

Alvaro Haroun-Izquierdo ◽

Andreas T Björklund ◽

Sarah Cooley ◽

Merete Thune Wiiger ◽

...

Keyword(s):

High Risk ◽

Nk Cells ◽

Board Of Directors ◽

Research Funding ◽

Nk Cell ◽

Scale Up ◽

Advisory Committees ◽

Equity Ownership ◽

Serial Killing ◽

Missing Self

Abstract Natural killer (NK) cells hold great promise as a source for allogeneic cell therapy against hematological malignancies, including acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). NK cell recognition of allogeneic tumors is strictly regulated by inhibitory killer cell immunoglobulin-like receptors (KIR) that bind to groups of HLA class I alleles. However, KIR expression on NK cells is highly diverse due to variation in gene content, polymorphism and copy number in combination with stochastic expression of the protein in individual cells. As a consequence, the number of efficacious allogeneic NK cells within a product isolated and expanded from random donors can vary a great deal and potentially be negligible. Our group has defined a repertoire of NK cells that is uniquely found in individuals with prior exposure to cytomegalovirus (CMV). Interestingly, these cells were shown to share many attributes usually reserved for adaptive immune cells including increased longevity, memory, and serial killing. We have previously described a 14-day protocol to enrich for adaptive NKG2C+CD57+ NK cells from CMV sero-positive donors with a homogenous expression of one single self-HLA specific KIR (self KIR). Here, we present new data on the GMP-transfer and clinical scale-up of this protocol, providing a route to off-the-shelf adaptive NK cell therapy for refractory high-risk AML/MDS. By screening >250 healthy donors, we first established the prerequisites for robust expansion of adaptive NK cells from peripheral blood of CMV+ donors and found that donors with >15% pre-existing adaptive NK cells showed efficient expansion of adaptive NK cells (Figure 1A-B). Apheresis products from a pool of pre-screened third-party donors are currently being collected for GMP freezing and use in an off-the-shelf setting intended for HLA mismatched patients to maximize alloreactivity by "missing" self. The GMP compatible protocol led to a robust expansion of clinical doses of self-KIR+ adaptive NK cells, with an average frequency of 60% self-specific KIR+ cells in the end product (Figure 1C-D). Based on the expression of self-KIR the expanded cells were educated, showing large dense-core granules and high levels of granzyme B. Further characterization in CyTOF using 36 phenotypic and functional markers revealed a highly activated state with high expression of DNAM-1 and CD2, which are critical for NK cell adhesion and function (Figure 1E). Notably, the expanded adaptive NK cells were negative for the HLA-E binding inhibitory receptor NKG2A, which is a major check point for T- and NK-cell based therapies. A microchip single-cell imaging platform revealed high serial killing capacity of the expanded adaptive NK cells. In flow cytometry-based killing assays and long-term killing assays this enhanced capacity for serial killing correlated with highly efficient targeting of mismatched PHA blasts (Figure 1F), tumor cell lines (Figure 1G), and MDS blasts. These pre-clinical data demonstrate the feasibility of off-the-shelf therapy with a non-engineered and yet highly specific NK cell population, representing the first route to clinical testing of missing self-recognition as it was originally defined over thirty years ago. Disclosures Valamehr: Fate Therapeutics Inc.: Employment. Alici:Vycellix: Consultancy, Equity Ownership, Patents & Royalties, Research Funding; Intellia: Membership on an entity's Board of Directors or advisory committees. Ljunggren:Fate Therapeutics: Patents & Royalties; Vycellix: Equity Ownership, Membership on an entity's Board of Directors or advisory committees. Malmberg:Fate Therapeutics Inc.: Consultancy, Research Funding.

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