scholarly journals Lirilumab Enhances Anti-Tumor Efficacy of Elotuzumab

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 4711-4711 ◽  
Author(s):  
Caroline Sola ◽  
Mathieu Blery ◽  
Cécile Bonnafous ◽  
Elodie Bonnet ◽  
Nicolas Fuseri ◽  
...  

Abstract Tumor cells that express reduced levels of Major Histocompatibility Complex (MHC) class I molecules may be recognized and killed by Natural Killer cells (NK cells), through a process known as “missing self” recognition. In humans, this is controlled by inhibitory receptors such as Killer Immunoglobulin-like Receptors (KIR) that recognize Human Leukocyte Antigen (HLA)-A, -B or –C. Engagement of KIR by HLA molecules results in inhibitory signaling that reduces NK cell-mediated natural killing and antibody-dependent cellular cytotoxicity (ADCC). Hence, antibodies that block interactions between inhibitory KIR and their HLA ligands are being evaluated as an anti-cancer therapeutic strategy. The anti-KIR2DL1/2/3-specific monoclonal antibody, lirilumab (BMS-986015 / IPH2102), is a fully human IgG4 that blocks binding of KIR to HLA-C, and is being developed for treating hematologic malignancies and solid tumors. Elotuzumab (BMS901608 / HuLuc63) is a humanized IgG1 anti-SLAMF7 (signaling lymphocyte activation molecule family member 7, CS-1) being developed for the treatment of Multiple Myeloma (MM). SLAMF7 is a cell surface glycoprotein highly expressed in myelomatous cells and only at low levels on normal cells. NK cell-mediated ADCC is one of the main mechanisms of action of elotuzumab, but ADCC is negatively regulated by KIR checkpoint receptors. Thus a combination of lirilumab and elotuzumab has strong scientific rationale. The aim of the present study was to assess whether lirilumab would enhance elotuzumab anti-MM activity in vitro with human peripheral blood NK cells and MM cell lines, and in vivo in a newly developed xenogenic mouse model. Two MM cell lines (OPM-2 and U266B1) were identified that express both HLA-C and SLAMF7. These MM cells were capable of activating peripheral blood NK cells from healthy donors in vitro, as assessed by three different endpoints (CD107 mobilization on NK cells surface and intracellular production of the cytokines IFN-g and TNF- a); each of these responses were significantly enhanced, in a dose-dependent manner, by both lirilumab and elotuzumab independently. Moreover, the elotuzumab-mediated functional activation of KIR2D+ NK cells could be further enhanced by the addition of increasing doses of lirilumab. The best combinatorial effect was observed in response to MM cells expressing low densities of SLAMF7. These data suggest that lirilumab treatment may increase the therapeutic efficacy of elotuzumab, particularly in MM patients with low SLAMF7 expression. In these experiments, it was not possible to clearly identify the impact of Fc receptor genotype or HLA-C genotype on the NK cell responses. To assess the therapeutic efficacy of lirilumab and elotuzumab in vivo, we generated a novel strain of double-transgenic mice expressing human KIR2DL3 as well as its ligand, HLA-cw3, on a Rag1-/- background (KIR-cw3-tgRAG mice), to allow engraftment of human MM tumor cells expressing SLAMF7. The OPM-2 MM cell line was subcutaneously engrafted in these mice and when high tumor volumes were reached, mice were treated with lirilumab, elotuzumab or a combination of both. As monotherapy, each of monoclonal antibody had some therapeutic effect while the combination of both resulted in a significantly stronger anti-tumor effect and increased survival of the mice. Median survival of mice treated with huIgG control was 38 days, 41 days with lirilumab, 42 days with elotuzumab and 51 days with both mAbs in combination (10 mice per group). In conclusion, we demonstrate that blockade of KIR checkpoint receptors with lirilumab was able to augment elotuzumab mediated ADCC in vitro and synergized with elotuzumab to mediate potent anti-MM activity in vivo. Taken together, these data provide a rationale for clinical trials to test combination treatment of lirilumab and elotuzumab in MM patients. Disclosures Sola: InnatePharma: Employment, Equity Ownership. Blery:Innate Pharma: Employment, Equity Ownership. Bonnafous:Innate Pharma: Employment, Equity Ownership. Bonnet:Innate Pharma: Employment, Equity Ownership. Fuseri:Innate Pharma: Employment, Equity Ownership. Graziano:Bristol-Myers Squibb: Employment; Bristol-Myers Squibb: Equity Ownership. Morel:Innate Pharma: Employment, Equity Ownership. André:Innate Pharma: Employment, Equity Ownership.

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 580-580
Author(s):  
Mark Wunderlich ◽  
Mahesh Shrestha ◽  
Lin Kang ◽  
Eric Law ◽  
Vladimir Jankovic ◽  
...  

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.


2020 ◽  
Vol 8 (1) ◽  
pp. e000131 ◽  
Author(s):  
Feng Li ◽  
Yuqiao Sheng ◽  
Weizhou Hou ◽  
Padma Sampath ◽  
Daniel Byrd ◽  
...  

BackgroundNatural killer (NK) cells have potent antitumor activities. Nevertheless, adoptive transfer therapy of NK cells has gained very limited success in patients with solid tumors as most infused NK cells remain circulating in the peripheral blood instead of entering tumor sites. Chemokines and their receptors play important roles in NK cell distribution. Enhancing chemokine receptors on immune cells to match and be driven to tumor-specific chemokines may improve the therapeutic efficacy of NK cells.MethodsThe CCR5-CCL5 axis is critical in NK cell homing to tumor sites. Thus, we analyzed CCR5 expression on NK cells from patients with cancer and healthy donors. We then upregulated CCR5 and CCL5 with lentiviruses and oncolytic viruses in NK and tumor cells, respectively. Animal experiments were also carried out to test the efficacy of the combination of oncolytic virus with NK cells.ResultsIn NK cells from patients with various solid tumors or healthy subjects, CCR5 was expressed at low levels before and after expansion in vitro. CCR5-engineered NK cells showed enhanced tumor infiltration and antitumor effects, but no complete regressions were noted in the in vivo tumor models. To further improve therapeutic efficacy, we constructed CCL5-expressing oncolytic vaccinia virus. In vitro data demonstrated that vaccinia virus can produce CCL5 in tumor cells while infectivity remained unaffected. Supernatants from tumor cells infected by CCL5-modified vaccinia virus enhanced the directional movement of CCR5-overexpressed NK cells but not green fluorescent protein (GFP)-expressing cells. More importantly, NK cells were resistant to the vaccinia virus and their functions were not affected after being in contact. In vivo assays demonstrated that CCL5-expressing vaccinia virus induced a greater accumulation of NK cells within tumor lesions compared with that of the prototype virus.ConclusionEnhancement of matched chemokines and chemokine receptors is a promising method of increasing NK cell homing and therapeutic effects. Oncolytic vaccinia viruses that express specific chemokines can synergistically augment the efficacies of NK cell-based therapy.


Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 4717-4717 ◽  
Author(s):  
Michael Robbins ◽  
Maria Jure-Kunkel ◽  
Gennaro Dito ◽  
Pascale Andre ◽  
Hui-fen Zhang ◽  
...  

Abstract Elotuzumab is a humanized monoclonal antibody (mAb) that binds specifically to Signaling Lymphocytic Activation Molecule F7 (SLAMF7, also known as CS1), a glycoprotein expressed on the surface of multiple myeloma (MM) tumor cells. SLAMF7 has not been detected on hematopoietic stem cells or on other normal tissues, but is expressed on some normal leukocytes, including natural killer (NK) cells. Elotuzumab enhances NK cell activation directly via SLAMF7 and also enhances NK cell-mediated antibody-dependent cell-mediated cytotoxicity (ADCC) of SLAMF7-expressing MM cells. NK cell-mediated ADCC can be enhanced by stimulating activating NK receptors as well as by blocking inhibitory NK receptors. IL-21 is a pleiotropic cytokine that has been shown to augment the ability of NK cells to mediate ADCC. CD137 (4-1BB) agonism has been shown to enhance both NK cell ADCC in vitro and the efficacy of a tumor-specific monoclonal antibody in a syngeneic mouse tumor model. NK cell-mediated ADCC can be reduced by inhibitory signaling via killer immunoglobulin-like receptors (KIRs) on NK cells, which recognize MHC class I molecules as ligands. Lirilumab is a human IgG4 mAb that binds inhibitory KIR2DL1/2/3, blocking interaction with HLA-C ligands and promoting NK cell activity. We investigated the ability of IL-21, agonistic CD137 mAb, and lirilumab to augment elotuzumab activity in vitro and in mouse models to support and guide clinical evaluation. Standard cytotoxicity assays were used to assess in vitro ADCC with human peripheral blood mononuclear cells or purified NK cells as effectors and SLAMF7-expressing tumor cells as targets. Flow cytometry was used to evaluate CD107a expression on NK cells. Efficacy was assessed in immunodeficient mice using a SLAMF7-expressing OPM2 human MM subcutaneous xenograft model. IL-21 was able to increase elotuzumab-mediated ADCC in vitro, but showed little or no enhancement of elotuzumab activity in the OPM2 tumor model. CD137 agonism showed minimal enhancement of elotuzumab ADCC in vitro, but was able to synergize with elotuzumab in vivo to mediate potent anti-tumor activity in the OPM2 xenograft tumor model. Tumors progressed in all eight of the mice treated with either buffer control or with anti-CD137 mAb alone. Of the eight mice treated with elotuzumab alone, one achieved a complete regression by the end of the study. In contrast, seven of eight mice in the group treated with both elotuzumab and anti-CD137 mAb achieved complete regression. Blocking the inhibitory KIR pathway with lirilumab augmented elotuzumab-mediated ADCC in vitro and synergized with elotuzumab to mediate potent anti-tumor activity using a mouse model expressing a KIR2DL3 transgene on a RAG-deficient background. Tumors progressed in all ten mice treated with either isotype control antibody or with lirilumab alone. Of the ten mice treated with elotuzumab alone, two achieved partial regressions and another mouse achieved a complete regression by the end of the study. Six of the ten mice in the group treated with both elotuzumab and lirilumab achieved complete regression and one mouse achieved a partial regression. Together, these approaches demonstrate that targeting activating and inhibitory receptors on NK cells can enhance or synergize with elotuzumab to increase NK cell ADCC towards myeloma cells. This study is being funded by Bristol-Myers Squibb. Editorial assistance was provided by Caudex Medical and was funded by Bristol-Myers Squibb. Disclosures Robbins: Bristol-Myers Squibb: Employment; Bristol-Myers Squibb: Equity Ownership. Jure-Kunkel:Bristol-Myers Squibb: Employment; Bristol-Myers Squibb: Equity Ownership. Dito:Bristol-Myers Squibb: Employment. Andre:Innate Pharma: Employment. Zhang:Bristol-Myers Squibb: Employment. Bezman:Bristol-Myers Squibb: Employment. Graziano:Bristol-Myers Squibb: Employment; Bristol-Myers Squibb: Equity Ownership.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 1844-1844
Author(s):  
John Richards ◽  
Myriam N Bouchlaka ◽  
Robyn J Puro ◽  
Ben J Capoccia ◽  
Ronald R Hiebsch ◽  
...  

AO-176 is a highly differentiated, humanized anti-CD47 IgG2 antibody that is unique among agents in this class of checkpoint inhibitors. AO-176 works by blocking the "don't eat me" signal, the standard mechanism of anti-CD47 antibodies, but also by directly killing tumor cells. Importantly, AO-176 binds preferentially to tumor cells, compared to normal cells, and binds even more potently to tumors in their acidic microenvironment (low pH). Hematological neoplasms are the fourth most frequently diagnosed cancers in both men and women and account for approximately 10% of all cancers. Here we describe AO-176, a highly differentiated anti-CD47 antibody that potently targets hematologic cancers in vitro and in vivo. As a single agent, AO-176 not only promotes phagocytosis (15-45%, EC50 = 0.33-4.1 µg/ml) of hematologic tumor cell lines (acute myeloid leukemia, non-Hodgkin's lymphoma, multiple myeloma, and T cell leukemia) but also directly targets and kills tumor cells (18-46% Annexin V positivity, EC50 = 0.63-10 µg/ml) in a non-ADCC manner. In combination with agents targeting CD20 (rituximab) or CD38 (daratumumab), AO-176 mediates enhanced phagocytosis of lymphoma and multiple myeloma cell lines, respectively. In vivo, AO-176 mediates potent monotherapy tumor growth inhibition of hematologic tumors including Raji B cell lymphoma and RPMI-8226 multiple myeloma xenograft models in a dose-dependent manner. Concomitant with tumor growth inhibition, immune cell infiltrates were observed with elevated numbers of macrophage and dendritic cells, along with increased pro-inflammatory cytokine levels in AO-176 treated animals. When combined with bortezomib, AO-176 was able to elicit complete tumor regression (100% CR in 10/10 animals treated with either 10 or 25 mg/kg AO-176 + 1 mg/kg bortezomib) with no detectable tumor out to 100 days at study termination. Overall survival was also greatly improved following combination therapy compared to animals treated with bortezomib or AO-176 alone. These data show that AO-176 exhibits promising monotherapy and combination therapy activity, both in vitro and in vivo, against hematologic cancers. These findings also add to the previously reported anti-tumor efficacy exhibited by AO-176 in solid tumor xenografts representing ovarian, gastric and breast cancer. With AO-176's highly differentiated MOA and binding characteristics, it may have the potential to improve upon the safety and efficacy profiles relative to other agents in this class. AO-176 is currently being evaluated in a Phase 1 clinical trial (NCT03834948) for the treatment of patients with select solid tumors. Disclosures Richards: Arch Oncology Inc.: Employment, Equity Ownership, Other: Salary. Bouchlaka:Arch Oncology Inc.: Consultancy, Equity Ownership. Puro:Arch Oncology Inc.: Employment, Equity Ownership. Capoccia:Arch Oncology Inc.: Employment, Equity Ownership. Hiebsch:Arch Oncology Inc.: Employment, Equity Ownership. Donio:Arch Oncology Inc.: Employment, Equity Ownership. Wilson:Arch Oncology Inc.: Employment, Equity Ownership. Chakraborty:Arch Oncology Inc.: Employment, Equity Ownership. Sung:Arch Oncology Inc.: Employment, Equity Ownership. Pereira:Arch Oncology Inc.: Employment, Equity Ownership.


Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 925-925 ◽  
Author(s):  
Andreas Lundqvist ◽  
Kristy Greeneltch ◽  
Maria Berg ◽  
Shivani Srivastava ◽  
Nanae Harashima ◽  
...  

Abstract Killer IgG like receptor (KIR) inactivation of NK cells by self HLA molecules has been proposed as a mechanism through which malignant cells evade host NK cell-mediated immunity. To overcome this limitation, we sought to develop a method to sensitize the patient’s tumor to autologous NK cell cytotoxicity. The proteasome inhibitor bortezomib has recently been shown to enhance the activity of tumor death receptors. We found that exposure of a variety of different leukemia, lymphoma and solid tumor cancer cell lines to sub-apoptotic doses of bortezomib sensitized tumor cells in vitro to lysis by allogeneic NK cells. Importantly, this sensitizing effect also occurs with autologous NK cells normally rendered inactive via tumor KIR ligands; NK cells expanded from patients with metastatic renal cell carcinoma were significantly more cytotoxic against the patient’s own autologous tumor cells when pretreated with bortezomib compared to untreated tumors. This sensitization to autologous NK cell killing was also observed in vivo in two different murine tumor models. A significant delay in tumor growth in C57BL/6 mice bearing LLC1 tumors (figure) and a delay in tumor growth and a significant prolongation (p<0.01) in survival were observed in RENCA tumor bearing Balb/c mice treated with bortezomib and syngeneic NK cell infusions compared to untreated mice or animals treated with bortezomib alone or NK cells alone. An investigation into the mechanism through which NK cell cytotoxicity was potentiated revealed bortezomib enhanced the activity of tumor death receptor-dependent and -independent apoptotic pathways. More specifically, bortezomib sensitized human and murine tumor cells to TRAIL and perforin/granzyme mediated NK cell cytotoxicity respectively. These observations suggest that pretreatment of malignant cells with bortezomib could be used as a strategy to override NK cell inhibition via tumor KIR ligands, thus potentiating the activity of adoptively infused autologous NK cells. A clinical trial evaluating the safety and anti-tumor efficacy of adoptively infused autologous NK cells in patients with advanced malignancies with and without tumor sensitization using bortezomib is currently being explored. Figure: Tumor growth in LLC1 bearing C57BL/6 mice. Fourteen days following s.c. injection of 3x105 LLC1 tumor cells, mice received 15μg (i.p) bortezomib and/or an adoptive infusion of 1x106 NK cells from C57BL/6 mice (i.v) given on day 15. Each dot represents the tumor volume of individual mice measured on day 28 post tumor injection. Tumors were significantly smaller in mice treated with bortezomib followed by NK cells compared to controls or mice that received either NK cells alone or bortezomib alone (p<0.04 for all groups). Figure:. Tumor growth in LLC1 bearing C57BL/6 mice. . / Fourteen days following s.c. injection of 3x105 LLC1 tumor cells, mice received 15μg (i.p) bortezomib and/or an adoptive infusion of 1x106 NK cells from C57BL/6 mice (i.v) given on day 15. Each dot represents the tumor volume of individual mice measured on day 28 post tumor injection. Tumors were significantly smaller in mice treated with bortezomib followed by NK cells compared to controls or mice that received either NK cells alone or bortezomib alone (p<0.04 for all groups).


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 3245-3245
Author(s):  
Ada H.V. Repetto-Llamazares ◽  
Roy Hartvig Larsen ◽  
Landsverk Kirsti ◽  
Trond Stokke ◽  
Bergthora Eiriksdottir ◽  
...  

Abstract Immunotherapy (IT) with the anti-CD20 monoclonal antibody rituximab in combination with chemotherapy has resulted in significantly improved response rate and survival in patients with various types of CD20 positive B-cell lymphoproliferative disorders. To be effective, rituximab depends on selective expression of a sufficient number of CD20 antigens per cell. Treatment with rituximab alone or in combination with chemotherapy can, however, result in disappearance of the CD20 expression, which may result in reduced clinical effect of subsequent CD20 targeted treatments. We have discovered that treatment of NHL in vitro and in vivo with the anti-CD37 antibody radionuclide conjugate (ARC) 177Lu-DOTA-HH1 (177Lu-HH1 or Betalutin™) results in an upregulation of the CD20 antigen expression, and therefore represents a rationale for a combination treatment with both agents. The in vitro expression of CD20 in Burkitt's Lymphoma, Daudi, cells 1-7 days after treatment with 177Lu-HH1 increased up to 120 % when compared with cells treated with unlabeled mAb, while Ramos (Burkitt's Lymphoma) and Rec-1 (Mantle Cell Lymphoma) cells showed 10 to 30 % increase, indicating a variation of the antigen upregulation in vitro with different cell lines. An upregulation of CD20 at the same order of magnitude was observed when cells where treated with similar absorbed radiation doses of external beam radiation. Treatment of nude mice with Ramos xenografts with 177Lu-HH1 resulted in a 3 times higher uptake of radiolabeled rituximab in tumor xenografts 5 days after start of treatment than in mice treated with unlabeled HH1 (p < 0.05) while uptake in normal organs was similar in both treatment groups (p > 0.05). SCID mice with intravenously injected Rec-1 cells were treated with NaCl, 100 mg rituximab, 40 MBq/kg 177Lu-HH1 or with the combination of 40 MBq/kg 177Lu-HH1 followed with 100 mg rituximab 5 days later. The combination of 177Lu-HH1 and rituximab resulted in significantly improved survival as compared with NaCl or rituximab alone, and a strong therapeutic gain as compared with 177Lu-HH1 alone (Table 1). In conclusion, 177Lu-HH1 treatment seems to improve uptake of rituximab and increase tumor suppression when used prior to anti-CD20 monoclonal antibody targeting in preclinical models. The reason for the upregulation of CD20 is probably related to the oxidative stress induced by the ARC-treatment, which will be evaluated in further studies. If the upregultation of CD20 is confirmed in clinical studies this effect could affect the way ARC and CD20 immunotherapy would be used in the future. Table 1. Therapy experiment groups and result Group Median ± SD Surviving fraction at the end of the study % Increase in symptom free survival compared to control NaCl + NaCl 64 ± 2 0.1 ---- NaCl + Rituximab 75 ± 10 0.3 15.4 177 Lu-HH1 + NaCl 92 ± 14 * 0.3 43.8 177 Lu-HH1 + Rituximab > 132 * 0.7 > 106.3 *Significantly different from NaCl + NaCl group (p < 0.01) Disclosures Repetto-Llamazares: Nordic Nanovector ASA: Employment, Equity Ownership. Larsen:Nordic Nanovector ASA: Equity Ownership, Membership on an entity's Board of Directors or advisory committees. Stokke:Nordic nanovector ASA: Equity Ownership. Generalov:Nordic Nanovector ASA: Employment. Dahle:Nordic Nanovector ASA: Employment, Equity Ownership.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 590-590 ◽  
Author(s):  
Alejandra Leivas ◽  
Paula Rio ◽  
Rebeca Mateos ◽  
Mari Liz Paciello ◽  
Almudena Garcia-Ortiz ◽  
...  

Abstract Introduction Immunotherapy represents a new weapon in the fight against multiple myeloma. Current clinical outcomes using CAR-T cell therapy against multiple myeloma show promise in the eradication of the disease. However, these CARs observe relapse as a common phenomenon after treatment due to the reemergence of neoantigens or negative cells. CARs can also be targeted using non-antibody approaches, including the use of receptors, as NKG2D with a wider range of ligands, and ligands to provide target specificity. Different cell types have been used to improve CAR cell therapy. CAR-T cells are the most commonly used. However, despite its effectiveness, there are still problems to face. The toxicity of the cytokine release syndrome is well known, that is why memory CD45RA- T cells are used to avoid collateral effects, although having lower efficacy. However, CAR-NK cells may have less toxicity and provide a method to redirect these cells specifically to refractory cancer. The objective of this work was to compare the anti-tumor activity of CAR-T, NKAEs and CAR-NK cells from multiple myeloma patients. Methods The activated and expanded NK cells (NKAE) were generated by coculture of peripheral blood mononuclear cells with the previously irradiated CSTX002 cell line. The CD45RA- T cells were obtained by depletion with CD45RA magnetic beads and subsequent culture. The NKAE and T were transduced with an NKG2D-CAR with signaling domains of 4-1BB and CD3z. The expansion of NKAE and the expression of NKG2D-CAR were evaluated by flow cytometry based on the percentage of NK cell population and transduction efficiency by the expression of NKG2D. Europium-TDA release assays (2-4 hours) were performed to evaluate in vitro cytotoxic activity. The antitumor activity of the NKAE (n=4) and CD45RA- (n=4) cells against MM U-266 cells was studied. Methylcellulose cultures were performed to assess the activity against the clonogenic tumor cell. In vivo studies were carried out in NSG mice receiving 5.106 of U266-luc MM cells i.v. injected at day 1. At day 4, mice received 15.106 i.v. injected of either CAR-NKAE or untransduced NKAE cells. Results In vitro. The killing activity of primary NKAE cells (n=4) was 86.6% (± 13.9%), considerably higher than that of CD45RA- lymphocytes (16.7% ± 13.6%) from the same patient (n=4). Even CD45RA- T cells from healthy donors (n=4) exhibit lower anti tumoral capacity (28.2% ± 9.7%) than NKAE cells. The transduction with an NKG2D CAR (MOI=5) improved the activity of autologous NKAE cells by 10% (96.4% ± 19%) leading to a nearly complete destruction of U-266 MM cells, and that of CD45RA- allogenic healthy cells in 19% (47.4% ± 12.6%). Nevertheless, CD45RA- autologous T cells transduced with NKG2D-CAR minimally improved their activity by 5.8% (22.5% ± 10.6%). Additionally, the CAR-NKAE cells were able to destroy the clonogenic tumor cell responsible for the progression of the MM from RPMI-8226 cell line. At an 8:1 ratio the CAR-NKAE cells were able to destroy 71.2% ± 2.5% of the clonogenic tumor cells, while the NKAE reached 56.5% ± 2.6% at a maximum ratio of 32: 1. The toxicity of the CAR-NKAE cells on healthy tissue from the same patient was assessed, and no activity against autologous PBMCs was observed, 1,8% at a maximun ratio of 32:1 (effector:target). In vivo. NKAE cells and CAR-NKAE cells were efficient in abrogating MM growth. However, CAR-NKAE cells treatment showed higher efficiency 14 days after tumor cells injection. Forty-two days after tumor cells injection, only animals receiving CAR-NKAE cells treatment remain free of disease (Figure 1). Conclusions It is feasible to modify primary NKAE cells and CD45RA- T cells from primary MM cells to safely express an NKG2D-CAR. Our data show that CD45RA- T cells from patients are not effective in vitro against MM even once transduced with our CAR. The resulting CAR-NKG2D NKAE cells are the most appropriate strategy for the destruction of MM in vitro and in vivo in our model. These results form the basis for the development of an NKG2D-CAR NK cell therapy in MM. Disclosures Rio: Rocket Pharmaceuticals Inc: Equity Ownership, Patents & Royalties, Research Funding. Lee:Merck, Sharp, and Dohme: Consultancy; Courier Therapeutics: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; CytoSen Therapeutics: Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Research Funding. Martinez-Lopez:Janssen: Honoraria, Research Funding; Celgene: Honoraria, Research Funding; Vivia: Honoraria; Pfizer: Research Funding; BMS: Research Funding; Novartis: Research Funding.


Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 991-991
Author(s):  
Pamela T. Manning ◽  
Benjamin J. Capoccia ◽  
Michael P. Rettig ◽  
Ronald R. Hiebsch ◽  
Robert W. Karr ◽  
...  

Abstract Recent success in immunomodulation of cancer has targeted immune checkpoints such as CTLA-4, PD-1 and PDL-1 to enhance adaptive immunity by stimulating production of tumor-selective, cytotoxic T cells. Anti-CD47mAbs enhance innate immunity by increasing the phagocytosis of tumor cells by macrophages leading to processing and presentation of tumor antigens to prime the adaptive T cell response. Many cancers, including hematologic cancers, up-regulate the expression of CD47 presumably to avoid immune destruction. Increased CD47 expression protects cancer cells from phagocytosis by sending a “don't eat me” signal to macrophages via SIRPalpha, an inhibitory receptor that prevents phagocytosis of CD47-bearing cells. CD47mAbs that block the CD47/SIRPalpha interaction (“blocking-only” mAbs) enhance phagocytosis of cancer cells in vitro. We have identified two CD47mAbs, Vx-1000 and Vx-1004, both of which block the CD47/SIRPalpha interaction and promote phagocytosis of tumor cells by macrophages equally well. However, Vx-1004 also has the unique property of killing cancer cells, but not normal blood cells, via a direct, cell-autonomous, cytotoxic mechanism. Therefore, Vx-1004 is a dual-function antibody. Vx-1004 selectively kills a variety of hematologic cancer cells in vitro, while Vx-1000, the blocking-only mAb, does not as assessed by annexin V staining and flow cytometry (Figure 1). In dose-response studies, cell death in leukemia cells was induced in 2 hrs by <1 ug="" vx-1004="" whereas="" normal="" peripheral="" blood="" mononuclear="" cells="" are="" resistant="" to="" the="" induction="" of="" cell="" death="" by="" following="" incubation="" with="" 10="" for="" 24="" hrs="" both="" these="" cd47mabs="" bind="" many="" species="" cd47="" including="" mouse="" and="" human="" p=""> To determine if the tumor-toxic activity of Vx-1004 confers enhanced efficacy in vivo compared to Vx-1000, we compared them in two mouse hematologic cancer models: murine acute promyelocytic leukemia (APL) and B cell lymphoma (BCL). Briefly, 1x106 GFP-labeled C57BL/6 APL cells were injected IV into wild-type C57BL/6 mice that were then treated IP with 0.4 mg/kg of either Vx-1000 or Vx-1004 on the day of tumor injection and on days 3 and 6 following tumor injection, a very low dose and limited dosing regimen. On day 25, the blood of these mice was analyzed for the number of circulating APL cells. As shown in Figure 2, Vx-1000 did not significantly reduce tumor burden compared to the control group. In contrast, Vx-1004 significantly reduced tumor burden compared to controls, demonstrating greater efficacy of the dual-function CD47mAb. In addition, enhanced efficacy of Vx-1004 compared to Vx-1000 was demonstrated in BCL (Figure 3). In this model, NSG mice were injected with 1x106 murine A20 lymphoma cells subcutaneously and then treated with 0.4mg/kg/day of the CD47mAbs IP for the first five days following tumor injection. In this model, Vx-1000 also failed to inhibit tumor growth compared to controls while Vx-1004 significantly reduced tumor burden at 35 days compared to both the control and Vx-1000 groups, nearly four weeks after treatment was stopped. These data demonstrate increased anti-cancer efficacy with a dual-function CD47mAb that not only blocks the CD47/SIRPalpha interaction to increase phagocytosis of cancer cells, but also selectively kills cancer cells. These studies indicate that dual-function CD47mAbs may have better anti-tumor activity in vivo and support their use in human clinical trials. Figure 1 Figure 1. Disclosures Manning: Corvus Pharmaceutical: Employment, Equity Ownership. Capoccia:Corvus Pharmaceutical: Employment, Equity Ownership. Hiebsch:Corvus Pharmaceutical: Employment, Equity Ownership. Karr:Corvus Pharmaceutical: Employment, Equity Ownership. Frazier:Corvus Pharmaceutical: Consultancy, Equity Ownership.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 4070-4070
Author(s):  
Harbani Malik ◽  
Ben Buelow ◽  
Udaya Rangaswamy ◽  
Aarti Balasubramani ◽  
Andrew Boudreau ◽  
...  

Introduction The restricted expression of CD19 in the B-cell lineage makes it an attractive target for the therapeutic treatment of B-cell malignancies. Many monoclonal antibodies and antibody drug conjugates targeting CD19 have been developed, including bispecific T-cell redirecting antibodies (T-BsAbs). In addition, anti-CD19 chimeric antigen receptor T-cells (CAR-T) have been approved to treat leukemia and lymphoma. However, despite the impressive depth of responses achieved by T-cell redirecting approaches such as T-BsAbs and CAR-T cells, toxicity from over-activation of T-cells remains a substantial limitation for this type of therapy, in particular neurotoxicity. In designing TNB-486, a novel CD19 x CD3 T-BsAb, we endeavored to retain activity against CD19-positive tumor cells while limiting the cytokine secretion thought to underlie toxicity from T-cell redirecting therapies. Utilizing TeneoSeek, a next generation sequencing (NGS)-based discovery pipeline that leverages in silico analysis of heavy chain only/fixed light chain antibody (HCA/Flic, respectively) sequences to enrich for antigen specific antibodies, we made a high affinity αCD19 HCA and a library of αCD3 Flic antibodies that showed a >2 log range of EC50s for T cell activation in vitro. Of note, the library contained a low-activating αCD3 that induced minimal cytokine secretion even at concentrations that mediated saturating T-cell dependent lysis of lymphoma cells (when paired with an αCD19 HCA). We characterized the relative efficacy and potential therapeutic window of this unique molecule, TNB-486, in vitro and in vivo and compared it to two strongly activating bispecific CD19 x CD3 antibodies similar to those currently available and in clinical development. Methods Affinity measurements of the αCD19 moiety were made via Biacore (protein) and flow cytometry (cell surface). Stability measurements were made by subjecting the molecule to thermal stress and the %aggregation was measured by Size Exclusion Chromatography. T-cell activation was measured via flow cytometry (CD69 and CD25 expression) and cytokine was measured by ELISA (IL-2, IL-6, IL-10, INF-ɣ, and TNFα) in vitro. Lysis of B-cell tumor cell lines (Raji, RI-1, and Nalm6) was measured via flow cytometry in vitro. In vivo, NOG mice were engrafted subcutaneously with NALM-6 or SUDHL-10 cells and intravenously with human peripheral blood mononuclear cells (huPBMC), and the mice treated with multiple doses of TNB-486 or negative or positive control antibody. Tumor burden was evaluated via caliper measurement. Pharmacodynamic/Pharmacokinetic (PK/PD) studies were performed in NOG mice. A pharmacokinetic (PK) study was performed in BALB/c mice, and a tolerability and PK study are ongoing in cynomolgus monkeys. Results TNB-486 bound to cell surface CD19 with single digit nanomolar affinity (~3nM). EC50s for cytotoxicity were in the single-digit nanomolar range for TNB-486, and sub-nanomolar for the strongly activating controls; TNB-486 maximum achievable lysis was identical to the positive controls. TNB-486 induced significantly less cytokine release for all cytokines tested compared to the positive controls even at doses saturating for tumor lysis. No off-target activation was observed in the absence of CD19 expressing target cells. In vivo, TNB-486 eradicated all CD19-positive tumors tested (NALM-6 and SUDHL10) at doses as little as 1µg administered every four days after tumors had reached ~200mm3. TNB-486 showed a PK profile consistent with other IgG molecules in mice (T1/2 ~6 days in mice). Conclusions TNB-486 induced comparable lysis of CD19-positive tumor cells as the strongly activating control bispecific antibodies while inducing significantly reduced cytokine secretion, even at doses saturating for tumor lysis in vitro. In vivo TNB-486 eradicated all tested CD19 positive tumor cell lines in established tumor models. No off-target binding was observed. In summary, TNB-486 shows promise as a lymphoma therapeutic differentiated from T-cell targeted therapies currently in the clinic and in clinical trials. Disclosures Malik: Teneobio, Inc.: Employment, Equity Ownership. Buelow:Teneobio, Inc.: Employment, Equity Ownership. Rangaswamy:Teneobio, Inc.: Employment, Equity Ownership. Balasubramani:Teneobio, Inc.: Employment, Equity Ownership. Boudreau:Teneobio, Inc.: Employment, Equity Ownership. Dang:Teneobio, Inc.: Employment, Equity Ownership. Davison:Teneobio, Inc.: Employment, Equity Ownership. Force Aldred:Teneobio, Inc.: Equity Ownership. Iyer:Teneobio, Inc.: Employment, Equity Ownership. Jorgensen:Teneobio, Inc.: Employment, Equity Ownership. Pham:Teneobio, Inc.: Employment, Equity Ownership. Prabhakar:Teneobio, Inc.: Employment, Equity Ownership. Schellenberger:Teneobio, Inc.: Employment, Equity Ownership. Ugamraj:Teneobio, Inc.: Employment, Equity Ownership. Trinklein:Teneobio, Inc.: Employment, Equity Ownership. Van Schooten:Teneobio, Inc.: Employment, Equity Ownership.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 210-210 ◽  
Author(s):  
Chen Xilin ◽  
Jianfeng Han ◽  
Chu Jianhong ◽  
Walter Meisen ◽  
Zhang Jianying ◽  
...  

Abstract Natural killer (NK) cells are innate lymphocytes that can rapidly eradicate tumor cells, especially those lacking MHC Class I molecules. NK cells can also rapidly eradicate herpes virus-infected cells. We designed an oncolytic herpes virus (oHSV) to selectively infect, replicate within, and lyse glioblastoma (GBM), a devastating brain tumor with a median survival of only 15 months following diagnosis. We have shown that the rapid influx of NK cells limits oHSV efficacy in GBM as they impede oHSV replication and spread [Alvarez-Breckenridge et al., Nat Med, 2012, 18(12):1827-34]. In the current study, we developed NK cell-based novel GBM therapies by decreasing the brain influx of NK cells to enhance the efficacy of oHSV, while arming NK cells in the brain with a chimeric antigen receptor (CAR) that targets both the wild-type EGFR and its mutant form EGFRvIII, two GBM tumor-associated antigens. We then investigated the synergistic effects between EGFR-CAR NK cells and oHSV. Transforming growth factor (TGF)-β is a potent immunosuppressive cytokine of NK cells [Yu et al, Immunity, 2006, 24(5):575-90]. We first determined if oHSV efficacy for treatment of GBM would be augmented by inhibiting anti-oHSV activity of NK cells with TGF-β pre-treatment. In vitro, NK cells pre-treated with TGF-β displayed less cytolytic capacity against oHSV-infected GBM cell lines and patient-derived GBM stem-like cells. In viral replication assays, co-culturing oHSV-infected GBM cells with NK cells pre-treated with TGF-β significantly increased virus titers. In an immunocompetent syngeneic GBM mouse model,administration of TGF-β to GBM-bearing mice prior to oHSV injection significantly inhibited intracranial infiltration and activation of NK cells (P < 0.05). In orthotopic human GBM xenograft mouse models and in syngeneic GBM mouse models, TGF-β treatment in vivo prior to oHSV therapy resulted in inhibition of NK cell infiltration, suppression of tumor growth and significantly prolonged survival of GBM-bearing mice (P < 0.05). Furthermore, depletion of NK cells incompletely blocked the positive effects of in vivo treatment of GBM with TGF-β on survival, suggesting that TGF-β may also directly act on other innate immune cells such as macrophages/microglia. These data demonstrate a single dose of TGF-β prior to oHSV administration enhances anti-tumor efficacy for GBM at least in part through the transient inhibition of the innate immune responses to oHSV infection. We next investigated whether NK cell activity could be enhanced to more directly target brain tumors while sparing eradication of oHSV. We therefore infected both human NK-92 cells and primary human NK cells to express the second generation CAR targeting both EGFR and EGFRvIII that we designed. Further, we asked if the treatment with EGFR-CAR NK cells plus oHSV could create a therapeutic synergy for the treatment to brain tumors. In vitro, compared with mock-transduced CAR-NK-cells, EGFR-CAR NK cells exhibited significantly higher cytotoxicity and IFN-γ production when co-cultured with tumor cells, for both NK-92 and primary NK cells (P < 0.01). Further, significantly higher cytolytic activity against tumor cells was obtained when CAR NK cells were combined with oHSV-1 infection of tumor cells, compared to either of the monotherapies alone (P < 0.05). In mice, to avoid oHSV clearance by the EGFR-CAR NK cells following the inoculation of the mouse with tumor cells, we administered these two agents sequentially; administering EGFR-CAR NK cells directly into the tumor first as a single injection of 2 × 106 cells, followed by intracranial infection with 2 × 105 plaque-forming units oHSV five days later, presumably after EGFR-CAR NK survival has diminished. Compared to vehicle controls, intracranial administration of either EGFR-CAR NK cells or oHSV blunted tumor growth. However, the combination of EGFR-CAR NK cells followed by oHSV infection resulted in significantly more efficient killing of tumor cells (P < 0.05) and significantly longer survival for tumor-bearing mice when compared to either monotherapy alone. Collectively, our studies demonstrate that in animal tumor models, we can combine novel NK cell and oHSV therapies to significantly improve survival. Disclosures No relevant conflicts of interest to declare.


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