scholarly journals T-Cell Suppression By Src/ABL Kinase Inhibitors When Combined with Blinatumomab in Ph+ Acute Lymphoblastic Leukemia

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 2694-2694 ◽  
Author(s):  
Jessica Leonard ◽  
Yoko Kosaka ◽  
Pavani Malla ◽  
Brandon Hayes-Lattin ◽  
Adam J. Lamble ◽  
...  
Keyword(s):  
T Cell ◽  
Board Of Directors ◽  
Research Funding ◽  
Kinase Inhibitors ◽  
Cell Function ◽  
Lymphoblastic Leukemia ◽  
Advisory Committees ◽  
Abl Kinase ◽  
Equity Ownership ◽  
Abl Kinase Inhibitors

Abstract Introduction: Targeted ABL kinase inhibitors (TKIs) have shown great activity in Ph+ Acute Lymphoblastic Leukemia (Ph+ ALL), however relapsed disease remains an unmet need. The bispecific antibody blinatumomab was recently approved as a single agent for use in patients with Ph+ ALL and there is much interest in combining this with targeted therapies. Second generation ABL kinase inhibitors inhibit both Src and LYN in addition to ABL. This is of particular interest in Ph+ ALL as LYN is important for leukemogenesis. T cell receptor (TCR) signaling is also dependent upon Src family kinase activity, and Src inhibitors may impact the efficacy of immunotherapies reliant on native T cell function. We sought to investigate the in vitro effects of ABL specific vs dual Src/ABL kinases on blinatumomab efficacy in both healthy donor as well as primary patient samples. Methods: We isolated peripheral blood mononuclear cells (PBMC) via Ficoll-Hypaque gradient from five healthy donors as well as from two patients with de novo and one patient with relapsed Ph+ ALL who harbored a T315I mutation. PBMC were labeled with CellTrace Violet and cultured for 5 days with no stimulation, blinatumomab, or blinatumomab in combination with imatinib, dasatinib, ponatinib or nilotinib at varying concentrations. Immunophenotyping was performed using multi-parameter flow cytometry for the following cell surface markers: CD45, CD3, CD4, CD8, CD56, and CD19. Blinatumomab efficacy was assessed by comparing the numbers of CD19+ / CD3- cells in untreated samples to those that had been treated with blinatumomab in the presence or absence of TKIs. Cell division of T cells was measured by CellTrace Violet dilution. Cytokine production was assessed via LEGENDplex Human Th Cytokine Panel. Levels of total Src, phospho-Src, total LCK and phospho-LCK were assessed via immunoblot. Results: After 5 days of exposure, blinatumomab led to T-cell proliferation in both healthy donor and patient PBMCs. Proliferation was observed in both CD8+ and CD4+ T cell subsets, although the effect was more pronounced in CD8+ cells. T cell proliferation, however, was completely suppressed by either dasatinib or ponatinib at nanomolar concentrations. This effect was far less pronounced with the ABL kinase inhibitors imatinib and nilotinib. Treatment of PBMCs with blinatumomab led to increased production of the cytokines IFN-g, IL-17-a and IL-22 in patient samples and healthy donors, while levels of IL-6 were increased in the patient samples only and levels of IL-10 in healthy subjects only. Cytokine production was absent in samples treated with blinatumomab and either dasatinib or ponatinib, while levels of IFN-g, IL-17a and IL-22 were minimally affected when blinatumomab was combined with imatinib. Immunoblots confirmed that dasatinib and ponatinib but not imatinib nor nilotinib inhibited phosphorylation of total Src as well as of LCK, likely explaining the inhibitory effects of these agents. In patient samples, blinatumomab alone and the TKIs alone greatly reduced the number of CD19+ cells. However, when dasatinib and blinatumomab were combined in the sample with a T315I mutation, there was little reduction in the percentage of CD19+ cells and no amplification of CD3+ cells, suggesting that dasatinib was able to inhibit the cytotoxic effects of blinatumomab with no effect to the leukemic cells. Discussion: Our results suggest that the combination of dual Src/ABL inhibitors with blinatumomab may abrogate the effects of blinatumomab by directly inhibiting T cell function. This is likely via inhibition of LCK, a known member of the TCR signaling pathway. Although small case series have reported responses in patients treated with blinatumomab and TKIs, it is possible that the majority of the response is from the TKI rather than blinatumomab. Only a randomized trial of a TKI +/- blinatumomab would be able to discern whether there is benefit of adding a dual Src/ABL TKI to bispecific antibody therapy. While our data are limited by sample numbers and by the fact that responses in living subjects may differ according to many other complex interactions in the in vivo immune microenvironment, the potential immunomodulatory effects of targeted therapies should be taken into consideration before they are combined with immunotherapies. Disclosures Leonard: Amgen: Research Funding. Druker:McGraw Hill: Patents & Royalties; Fred Hutchinson Cancer Research Center: Research Funding; Amgen: Membership on an entity's Board of Directors or advisory committees; ARIAD: Research Funding; Monojul: Consultancy; Millipore: Patents & Royalties; Novartis Pharmaceuticals: Research Funding; Oregon Health & Science University: Patents & Royalties; Leukemia & Lymphoma Society: Membership on an entity's Board of Directors or advisory committees, Research Funding; Bristol-Meyers Squibb: Research Funding; ALLCRON: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy; Gilead Sciences: Consultancy, Membership on an entity's Board of Directors or advisory committees; Blueprint Medicines: Consultancy, Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Cepheid: Consultancy, Membership on an entity's Board of Directors or advisory committees; Beta Cat: Membership on an entity's Board of Directors or advisory committees; MolecularMD: Consultancy, Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Patient True Talk: Consultancy; Vivid Biosciences: Membership on an entity's Board of Directors or advisory committees; Third Coast Therapeutics: Membership on an entity's Board of Directors or advisory committees; GRAIL: Consultancy, Membership on an entity's Board of Directors or advisory committees; Aileron Therapeutics: Consultancy; Henry Stewart Talks: Patents & Royalties; Aptose Therapeutics: Consultancy, Equity Ownership, Membership on an entity's Board of Directors or advisory committees. Tyner:Constellation: Research Funding; Vivid Biosciences: Membership on an entity's Board of Directors or advisory committees; Janssen: Research Funding; Gilead: Research Funding; Aptose: Research Funding; Incyte: Research Funding; Genentech: Research Funding; Array: Research Funding; Takeda: Research Funding; AstraZeneca: Research Funding. Lind:Celgene: Research Funding; Janssen Pharmaceutical R&D: Research Funding; Amgen: Research Funding; Fluidigm: Honoraria; Monojul: Research Funding.

scholarly journals Therapeutic Targeting of Mertk and BCL-2 in T-Cell and Early T-Precursor Acute Lymphoblastic Leukemia

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 1184-1184
Author(s):  
Ryan J Summers ◽  
Juhi Jain ◽  
Eleana Vasileiadi ◽  
Brittany Smith ◽  
Madison Stout ◽  
...  
Keyword(s):  
T Cell ◽  
Board Of Directors ◽  
Research Funding ◽  
Lymphoblastic Leukemia ◽  
Xenograft Model ◽  
Prolonged Survival ◽  
Cell Phenotype ◽  
Advisory Committees ◽  
Equity Ownership

Abstract Introduction T-cell acute lymphoblastic leukemia (T-ALL) accounts for 15% of childhood ALL and is associated with inferior outcomes relative to B-cell ALL. Early T-precursor ALL (ETP-ALL) is a subset of T-ALL characterized by an immature T cell phenotype, resistance to therapy, and high rates of induction failure. MERTK receptor tyrosine kinase is ectopically expressed in 40-50% of T-ALLs, particularly those with an immature T cell phenotype, suggesting a role in ETP-ALL. Inhibition of MERTK using shRNA delayed leukemia progression and prolonged survival in a T-ALL xenograft model, implicating MERTK as a therapeutic target. MRX-2843 is an orally available dual MERTK/FLT3 inhibitor currently in phase I clinical trials. The anti-apoptotic protein B-cell lymphoma-2 (BCL-2) is specifically expressed in immature T cell precursors, is preferentially expressed in ETP-ALL compared to other T-ALLs, is essential for ETP-ALL cell survival, and is regulated downstream of MERTK in acute leukemia cells. Thus, combination therapies targeting these two proteins may be particularly effective to treat ETP-ALL. Methods Loucy and PEER ETP-ALL cell lines were cultured with vehicle or MRX-2843. Phosphorylated and total MERTK were assessed by immunoblot. Relative cell numbers were measured using Presto Blue reagent. Cells were stained with PoPro-1-iodide and propidium iodide and apoptotic and dead cells were quantitated by flow cytometry. T-ALL patient samples were cultured with UNC2025, a close analogue of MRX-2843, and relative cell numbers were assessed using MTS reagent. Orthotopic xenografts were established in NSG or NSGS mice using luciferase-expressing Jurkat cells (T-ALL), luciferase-expressing Loucy cells (ETP-ALL) or an ETP-ALL patient sample and leukemia burden was monitored by bioluminescence imaging or flow cytometry. MRX-2843 (65 mg/kg or 75 mg/kg) or saline vehicle were administered orally once daily. Differences in disease burden were assessed with the Mann-Whitney-U test or one-way ANOVA. Survival was determined by Kaplan-Meier analysis. Loucy and PEER cells were plated and screened in quadruplicate against >150 pairwise combinations of MRX-2843 and the BCL-2 inhibitor venetoclax in a high-throughput format. Synergy was calculated using the response additivity model. Results Treatment with MRX-2843 mediated a dose-dependent decrease in phosphorylated MERTK, inhibited expansion of ETP-ALL cells, and induced cell death in vitro. Fifty-four percent (21/39) of primary T-ALL patient samples were sensitive to UNC2025 with an IC 50≤550 nM, including 2/5 (40%) pediatric samples and 10/19 (53%) adolescent/young adult samples. Treatment with MRX-2843 significantly reduced leukemia burden in cell line-derived T-ALL and ETP-ALL xenograft models and prolonged survival by 50% and 13% in the T-ALL (n=10, p<0.0001) and ETP-ALL (n=10, p=0.0136) models, respectively. Similarly, in a patient-derived ETP-ALL xenograft model, treatment with MRX-2843 reduced peripheral blood disease burden by 83% and spleen weight by 64% compared to vehicle-treated mice (n=8, p<0.001) and prolonged survival by 41% (n=8, p=0.0016). MRX-2843 mediated anti-leukemia activity in combination with venetoclax and a dose ratio of 1:20 MRX-2843:venetoclax provided optimal synergy in Loucy and PEER ETP-ALL cells in vitro (Figure 1). Conclusions MRX-2843 has therapeutic activity in ETP-ALL cell culture and xenograft models and over half of T-ALL patient samples were sensitive to MERTK/FLT3 inhibition. MRX-2843 also mediated synergistic anti-leukemia activity against ETP-ALL cells in combination with venetoclax, with an optimal molar ratio of 1:20. These data demonstrate the therapeutic potential of MRX-2843 in patients with T-ALL, suggest that MRX-2843 may be particularly active alone and in combination with venetoclax in the ETP-ALL subset, and provide rationale for clinical testing of MRX-2843, with the ultimate goal to progress to trials evaluating MRX-2843 in combination with other agents. Toward this end, MRX-2843 monotherapy will be tested in patients with relapsed leukemia in an upcoming clinical trial (NCT04872478). Figure 1 Figure 1. Disclosures Wang: Meryx: Other: Equity ownership; University of North Carolina: Patents & Royalties. Frye: University of North Carolina: Patents & Royalties; Meryx: Membership on an entity's Board of Directors or advisory committees, Other: Equity ownership. Earp: Meryx: Membership on an entity's Board of Directors or advisory committees, Other: Equity ownership. Tyner: Petra: Research Funding; Incyte: Research Funding; Takeda: Research Funding; Janssen: Research Funding; Astrazeneca: Research Funding; Array: Research Funding; Constellation: Research Funding; Seattle Genetics: Research Funding; Schrodinger: Research Funding; Genentech: Research Funding; Gilead: Research Funding; Agios: Research Funding. DeRyckere: Meryx: Other: Equity ownership. Graham: Meryx: Membership on an entity's Board of Directors or advisory committees, Other: Equity ownership.

scholarly journals Biology of LAG3 Checkpoint Blockade

Blood ◽  
2017 ◽  
Vol 130 (Suppl_1) ◽  
pp. SCI-36-SCI-36
Author(s):  
Dario A.A. Vignali
Keyword(s):  
T Cell ◽  
Board Of Directors ◽  
Immune Regulation ◽  
Research Funding ◽  
Cell Function ◽  
Inhibitory Receptor ◽  
Advisory Committees ◽  
Equity Ownership ◽  
Mouse Models Of Cancer ◽  
The Impact

Abstract Dr. Vignali will discuss the biology of the inhibitory receptor LAG3, and its contribution to T cell exhaustion and immune regulation on CD8+ and CD4+ intratumoral T cells in mouse models of cancer and autoimmunity, and in a variety of human malignancies. He will also discuss the impact of LAG3 on regulatory T cell function. Given the considerable interest in inhibitory receptors in general, and LAG3 recently, as immunotherapeutic targets, he will also discuss how differential LAG3 expression could impact responsiveness to immunotherapy. Disclosures Vignali: Potenza Therapeutics: Consultancy, Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties: Licensed IP, Research Funding; Tizona Therapeutics: Consultancy, Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding; Oncorus: Consultancy, Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Pieris: Membership on an entity's Board of Directors or advisory committees; FStar: Membership on an entity's Board of Directors or advisory committees; BMS: Equity Ownership; Merck: Equity Ownership; Crescendo: Consultancy; Intellia: Consultancy; MPM: Consultancy; Onkaido/Moderna: Consultancy; Servier: Consultancy.

scholarly journals Increased Early Mortality after Fludarabine and Melphalan Conditioning with Peripheral Blood Grafts in Haploidentical SCT with Post-Transplant Cyclophosphamide

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 4496-4496 ◽  
Author(s):  
Luke Eastburg ◽  
David A. Russler-Germain ◽  
Ramzi Abboud ◽  
Peter Westervelt ◽  
John F. DiPersio ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Stem Cell ◽  
T Cell ◽  
Board Of Directors ◽  
Research Funding ◽  
Early Mortality ◽  
Cell Transplant ◽  
Advisory Committees ◽  
Post Transplant ◽  
Equity Ownership

The use of post-transplant cyclophosphamide (PTCy) in the context of haploidentical stem cell transplant (haplo-SCT) has led to drastically reduced rates of Graft-vs-Host (GvH) disease through selective depletion of highly allo-reactive donor T-cells. Early trials utilized a reduced-intensity Flu/Cy/TBI preparative regimen and bone marrow grafts; however, relapse rates remained relatively high (Luznik et al. BBMT. 2008). This led to the increased use of myeloablative (MA) regimens for haplo-SCT, which have been associated with decreased relapse rates (Bashey et al. J Clin Oncol. 2013). Most studies have used a MA total body irradiation (TBI) based regimen for haplo-SCT. Preparative regimens using fludarabine and melphalan (FluMel), with or without thiotepa, ATG, and/or low dose TBI have also been reported using bone marrow grafts. Reports on the safety and toxicity of FluMel in the haplo-SCT setting with PTCy and peripheral blood stem cell (PBSC) grafts are lacking. In this two-center retrospective analysis, the safety/toxicity of FluMel as conditioning for haplo-SCT was evaluated. We report increased early mortality and toxicity using standard FluMel conditioning and PBSC grafts for patients undergoing haplo-SCT with PTCy. 38 patients at the University of Rochester Medical Center and the Washington University School of Medicine underwent haplo-SCT with FluMel conditioning and PBSC grafts between 2015-2019. Outcomes were measured by retrospective chart review through July 2019. 34 patients (89.5%) received FluMel(140 mg/m2). Two patients received FluMel(100 mg/m2) and two patients received FluMel(140 mg/m2) + ATG. The median age at time of haplo-SCT was 60 years (range 21-73). 20 patients were transplanted for AML, eight for MDS, two for PMF, two for NHL, and five for other malignancies. The median Hematopoietic Cell Transplantation-specific Comorbidity Index (HCT-CI) score was 4 (≥3 indicates high risk). 11 patients had a history of prior stem cell transplant, and 16 patients had active disease prior to their haplo-SCT. Seven patients had sex mismatch with their stem cell donor. Median donor age was 42 (range 21-71). 20 patient deaths occurred by July 2019 with a median follow up of 244 days for surviving patients. Nine patients died before day +100 (D100, "early mortality"), with a D100 non-relapse mortality (NRM) rate of 24%. Median overall and relapse free survival (OS and RFS, respectively) were 197 days (95% CI 142-not reached) and 180 days (95% CI 141-not reached), respectively, for the entire cohort. The 1 year OS and NRM were 29% and 50%. The incidence of grades 2-4cytokine release syndrome (CRS) was 66%, and 52% of these patients were treated with tocilizumab. CRS was strongly associated with early mortality, with D100 NRM of 36% in patients with grade 2-4 CRS compared to 0% in those with grade 0-1. The incidence of acute kidney injury (AKI) was 64% in patients with grade 2-4 CRS, and 8% in those without (p < 0.001). 28% of patients with AKI required dialysis. Grade 2-4 CRS was seen in 54% of patients in remission prior to haplo-SCT and in 92% of those with active disease (p = 0.02). Of the 9 patients with early mortality, 89% had AKI, 44% needed dialysis, and 100% had grade 2-4 CRS, compared to 31%, 10%, and 55% in those without early mortality (p = 0.002, p = 0.02, p = 0.01). Early mortality was not significantly associated with age, HCT-CI score, second transplant, disease status at transplant, total dose of melphalan, volume overload/diuretic use, or post-transplant infection. In conclusion, we observed a very high rate of NRM with FluMel conditioning and PBSC grafts for haplo-SCT with PTCy. The pattern of toxicity was strongly associated with grade 2-4 CRS, AKI, and need for dialysis. These complications may be mediated by excessive inflammation in the context of allo-reactive donor T-cell over-activation. Consistent with this, multiple groups have shown that FluMel conditioning in haplo-SCT is safe when using bone marrow or T-cell depleted grafts. Based on our institutional experiences, we would discourage the use of FluMel as conditioning for haplo-SCT with PTCy with T-cell replete PBSC grafts. Alternative regimens or variations on melphalan-based regimens, such as fractionated melphalan dosing or inclusion of TBI may improve outcomes but further study and randomized controlled trials are needed. This study is limited in its retrospective design and sample size. Figure Disclosures DiPersio: WUGEN: Equity Ownership, Patents & Royalties, Research Funding; Karyopharm Therapeutics: Consultancy; Magenta Therapeutics: Equity Ownership; Celgene: Consultancy; Cellworks Group, Inc.: Membership on an entity's Board of Directors or advisory committees; NeoImmune Tech: Research Funding; Amphivena Therapeutics: Consultancy, Research Funding; Bioline Rx: Research Funding, Speakers Bureau; Macrogenics: Research Funding, Speakers Bureau; Incyte: Consultancy, Research Funding; RiverVest Venture Partners Arch Oncology: Consultancy, Membership on an entity's Board of Directors or advisory committees. Liesveld:Onconova: Other: Data safety monitoring board; Abbvie: Membership on an entity's Board of Directors or advisory committees.

Inhibition of USP10 Induces Degradation of Oncogenic FLT3: A Novel Approach to Therapy of Leukemia

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 524-524
Author(s):  
Sara Buhrlage ◽  
Ellen Weisberg ◽  
Nathan Schauer ◽  
Jing Yang ◽  
Ilaria Lamberto ◽  
...  
Keyword(s):  
Board Of Directors ◽  
Research Funding ◽  
Kinase Inhibitors ◽  
Kinase Inhibitor ◽  
Leukemia Cell ◽  
Initial Assessment ◽  
Large Trial ◽  
Newly Diagnosed ◽  
Advisory Committees ◽  
Equity Ownership

Abstract Acute myeloid leukemia (AML) is the most common type of acute leukemia in adults. Overall, the survival with current chemotherapy is only 20-40%, declining steadily with advancing age. Approximately 30% of AML patients have mutations that constitutively activate the FLT3 gene. The most common FLT3 mutation results in tandem duplications within the juxtamembrane domain, observed in 20-25% of AML patients (internal tandem duplication, ITD), associated with markedly decreased survival. FLT3 kinase domain inhibitors, including SU11248, SU5416, CEP-701 and PKC412 (midostaurin), have been shown to induce partial, and usually brief, remissions in clinical trials of relapsed AML patients when administered as single agents. In a large trial in newly diagnosed patients, however, midostaurin was shown to increase survival when combined with standard chemotherapy.[1] This study supports the notion that inhibition of FLT3 may be important, at least in patients with mutations in the FLT3 gene. Since drug resistance develops in some patients with newly diagnosed AML and virtually all patients with advanced disease, additional strategies to target FLT3 would be of value. We discovered that the deubiquitinating enzyme (DUB) ubiquitin specific protease 10 (USP10) removes a degradative ubiquitin tag from mutant FLT3 thereby contributing to high levels of the oncogenic protein in AML (Fig 1a). Screening of our preclinical DUB inhibitor library for ability to selectively kill growth factor-independent FLT3-ITD-positive Ba/F3 cells over IL-3-dependent parental Ba/F3 cells identified HBX19818, a reported USP7 inhibitor, as the top hit. The effects are not unique to the Ba/F3 system: when profiled against a panel of 7 leukemia cell lines, HBX19818 conferred a substantial growth suppressive effect only to those expressing the FLT3-ITD oncoprotein (Fig 1b). As an initial assessment of the mechanism of HBX19818 we confirmed that it does promote ubiquitin-mediated degradation of FLT3-ITD (Fig 1c) and that the effect is selective as HBX19818 does not impact protein levels of wt FLT3. HBX19818 is published as an irreversible USP7 inhibitor,[2] however DUBome selectivity profiling data we generated identifies USP10 as the most potently inhibited DUB of the compound (USP10 IC50 = 14 µM). We went on to validate USP10 as the DUB that stabilizes FLT3-ITD using a combination of small molecule and genetic experiments. Notably, HBX19818 binds and inhibits USP10 in cells (data not shown), small hairpin knockdown of USP10 phenocopies the antiproliferative and FLT3 degradation effects of HBX19818 (Figure 1d and data not shown), and a direct interaction between USP10 and FLT3-ITD is observed in co-immunoprecipitation experiments (Fig 1e). Additionally, SAR studies reveal correlation among USP10 IC50, FLT3-ITD degradation and anti-proliferative effects for the HBX19818 chemical series, and we identified a second chemotype that phenocopies its effects. In support of the translational potential of USP10 inhibition for FLT3 mutant AML, we observed that both USP10 inhibitor series synergize with FLT3 kinase inhibitors, suppress growth of mutant FLT3-expressing primary AML cells and primagraft AML cells and, importantly, display the ability to overcome the FLT3 inhibitor-resistant mutant FLT3-ITD-F691L among other FLT3 kinase inhibitor-resistant mutants (Fig. 1f and data not shown). Overall, our data strongly support degradation of mutant FLT3 as an alternative approach to therapeutically target FLT3. This approach, which focuses on targeting USP10, could prove more efficacious than kinase inhibitors by simultaneously blocking both enzymatic and scaffolding functions of FLT3, and blocking compensatory increases in FLT3 protein or resistant point mutations associated with some kinase inhibitors. Importantly, this is the first demonstration of stabilization of an AML mutant driver protein by a DUB enzyme and introduces a novel therapy for FLT3 mutant-positive AML. References: 1. Stone, R.M., ASH, 2015. 2. Reverdy, C., et al., Chem Biol, 2012. 19, 467-77. Figure 1. Figure 1. Disclosures Weisberg: novartis: Research Funding. Weinstock:Novartis: Consultancy, Research Funding. Stone:Celator: Consultancy; Pfizer: Consultancy; Xenetic Biosciences: Consultancy; Novartis: Consultancy; Seattle Genetics: Consultancy; Roche: Consultancy; Amgen: Consultancy; ONO: Consultancy; Xenetic Biosciences: Consultancy; Sunesis Pharmaceuticals: Consultancy; Juno Therapeutics: Consultancy; Sunesis Pharmaceuticals: Consultancy; Karyopharm: Consultancy; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees; Merck: Consultancy; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees; Seattle Genetics: Consultancy; Agios: Consultancy; Jansen: Consultancy. Gray:Gatekeeper: Equity Ownership; Petra: Consultancy, Equity Ownership; C4: Consultancy, Equity Ownership; Syros: Consultancy, Equity Ownership. Griffin:Janssen: Research Funding; Novartis: Consultancy, Research Funding.

scholarly journals Development and Evaluation of a Human Single Chain Variable Fragment (scFv) Derived Bcma Targeted CAR T Cell Vector Leads to a High Objective Response Rate in Patients with Advanced MM

Blood ◽  
2017 ◽  
Vol 130 (Suppl_1) ◽  
pp. 742-742 ◽  
Author(s):  
Eric L Smith ◽  
Sham Mailankody ◽  
Arnab Ghosh ◽  
Reed Masakayan ◽  
Mette Staehr ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Board Of Directors ◽  
Research Funding ◽  
Employment Equity ◽  
Advisory Committees ◽  
Car T Cells ◽  
Car T Cell ◽  
Car T ◽  
Equity Ownership

Abstract Patients with relapsed/refractory MM (RRMM) rarely obtain durable remissions with available therapies. Clinical use of BCMA targeted CAR T cell therapy was first reported in 12/2015 for RRMM, and based on small numbers, preliminary results appear promising. Given that host immune anti-murine CAR responses have limited the efficacy of repeat dosing (Turtle C. Sci Trans Med 2016), our goal was to develop a human BCMA targeted CAR T cell vector for clinical translation. We screened a human B cell derived scFv phage display library containing 6x1010 scFvs with BCMA expressing NIH 3T3 cells, and validated results on human MM cell lines. 57 unique and diverse BCMA specific scFvs were identified containing light and heavy chain CDR's each covering 6 subfamilies, with HCDR3 length ranges from 5-18 amino acids. 17 scFvs met stringent specificity criteria, and a diverse set was cloned into CAR vectors with either a CD28 or a 4-1BB co-stimulatory domain. Donor T cells transduced with BCMA targeted CAR vectors that conveyed particularly desirable properties over multiple in vitro assays, including: cytotoxicity on human MM cell lines at low E:T ratios (&gt;90% lysis, 1:1, 16h), robust proliferation after repeat antigen stimulation (up to 700 fold, stimulation q3-4d for 14d), and active cytokine profiling, were selected for in vivo studies using a marrow predominant human MM cell line model in NSG mice. A single IV injection of CAR T cells, either early (4d) or late (21d) after MM engraftment was evaluated. In both cases survival was increased when treated with BCMA targeted CAR T cells vs CD19 targeted CAR T cells (median OS at 60d NR vs 35d p&lt;0.05). Tumor and CAR T cells were imaged in vivo by taking advantage of luciferase constructs with different substrates. Results show rapid tumor clearance, peak (&gt;10,000 fold) CAR T expansion at day 6, followed by contraction of CAR T cells after MM clearance, confirming the efficacy of the anti-BCMA scFv/4-1BB containing construct. Co-culture with primary cells from a range of normal tissues did not activate CAR T cells as noted by a lack of IFN release. Co-culture of 293 cells expressing this scFv with those expressing a library of other TNFRSF or Ig receptor members demonstrated specific binding to BCMA. GLP toxicity studies in mice showed no unexpected adverse events. We generated a retroviral construct for clinical use including a truncated epithelial growth factor receptor (EGFRt) elimination gene: EGFRt/hBCMA-41BBz. Clinical investigation of this construct is underway in a dose escalation, single institution trial. Enrollment is completed on 2/4 planned dose levels (DL). On DL1 pts received cyclophosphamide conditioning (3g/m2 x1) and 72x106 mean CAR+ T cells. On DL2 pts received lower dose cyclophosphamide/fludarabine (300/30 mg/m2 x3) and 137x106 mean CAR+ T cells. All pts screened for BCMA expression by IHC were eligible. High risk cytogenetics were present in 4/6 pts. Median prior lines of therapy was 7; all pts had IMiD, PI, high dose melphalan, and CD38 directed therapies. With a data cut off of 7/20/17, 6 pts are evaluable for safety. There were no DLT's. At DL1, grade 1 CRS, not requiring intervention, occurred in 1/3 pts. At DL2, grade 1/2 CRS occurred in 2/3 pts; both received IL6R directed Tocilizumab (Toci) with near immediate resolution. In these 2 pts time to onset of fever was a mean 2d, Tmax was 39.4-41.1 C, peak CRP was 25-27mg/dl, peak IL6 level pre and post Toci were 558-632 and 3375-9071 pg/ml, respectively. Additional serum cytokines increased &gt;10 fold from baseline in both pts include: IFNg, GM CSF, Fractalkine, IL5, IL8, and IP10. Increases in ferritin were limited, and there were no cases of hypofibrinogenemia. There were no grade 3-5 CRS and no neurotoxicities or cerebral edema. No pts received steroids or Cetuximab. Median time to count recovery after neutropenia was 10d (range 6-15d). Objective responses by IMWG criteria after a single dose of CAR T cells were observed across both DLs. At DL1, of 3 pts, responses were 1 VGPR, 1 SD, and 1 pt treated with baseline Mspike 0.46, thus not evaluable by IMWG criteria, had &gt;50% reduction in Mspike, and normalization of K/L ratio. At DL2, 2/2 pts had objective responses with 1 PR and 1 VGPR (baseline 95% marrow involvement); 1 pt is too early to evaluate. As we are employing a human CAR, the study was designed to allow for an optional second dose in pts that do not reach CR. We have treated 2 pts with a second dose, and longer follow up data is pending. Figure 1 Figure 1. Disclosures Smith: Juno Therapeutics: Membership on an entity's Board of Directors or advisory committees, Patents & Royalties: BCMA targeted CAR T cells, Research Funding. Almo: Cue Biopharma: Other: Founder, head of SABequity holder; Institute for Protein Innovation: Consultancy; AKIN GUMP STRAUSS HAUER & FELD LLP: Consultancy. Wang: Eureka Therapeutics Inc.: Employment, Equity Ownership. Xu: Eureka Therapeutics, Inc: Employment, Equity Ownership. Park: Amgen: Consultancy. Curran: Juno Therapeutics: Research Funding; Novartis: Consultancy. Dogan: Celgene: Consultancy; Peer Review Institute: Consultancy; Roche Pharmaceuticals: Consultancy; Novartis: 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. Liu: Eureka Therpeutics Inc.: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties. Brentjens: Juno Therapeutics: Consultancy, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties, Research Funding.

scholarly journals Adoptive T-Cell Therapy for Acute Lymphoblastic Leukemia Targeting Multiple Tumor Associated Antigens

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 2693-2693
Author(s):  
Swati Naik ◽  
Premal Lulla ◽  
Ifigeneia Tzannou ◽  
Robert A. Krance ◽  
George Carrum ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Board Of Directors ◽  
Research Funding ◽  
Disease Relapse ◽  
Advisory Committees ◽  
Leukemic Relapse ◽  
Post Infusion ◽  
Equity Ownership ◽  
T Cell Lines

Abstract Background: Leukemic relapse remains the major cause of treatment failure in hematopoietic stem cell transplant (HSCT) recipients. While the infusion of donor lymphocytes to prevent and treat relapse has been clinically implemented this strategy does not provide durable remissions and carries the risk of life-threatening graft-versus-host disease (GVHD). More recently the adoptive transfer of T cells that have been engineered to express CD19-targeted chimeric antigen receptors (CARs), has shown potent anti-leukemic activity in HSCT recipients with recurrent disease. However, disease relapse with the emergence of CD19 negative tumors is an emerging clinical issue post-administration of these mono-targeted T cells. To overcome these limitations, we developed a protocol for the generation of donor-derived T cell lines that simultaneously targeted a range of tumor associated antigens (multiTAAs) that are frequently expressed by B- and T-cell ALL including PRAME, WT1 and Survivin for adoptive transfer to high risk recipients transplanted for ALL. Methods/Results: We were consistently able to generate donor-derived multiTAA-specific T cells by culturing PBMCs in the presence of a Th1-polarizing/pro-proliferative cytokine cocktail, using autologous DCs as APCs and loading them with pepmixes (15 mer peptides overlapping by 11 amino acids) spanning all 3 target antigens. The use of whole antigen increases the range of patient HLA polymorphisms that can be exploited beyond those matched to single peptides, while targeting multiple antigens simultaneously reduces the risk of tumor immune evasion. To date, we have generated 14 clinical grade multiTAA-specific T cell lines comprising CD3+ T cells (mean 94±9%) with a mixture of CD4+ (mean 21±28%) and CD8+ (mean 52±24 %) cells, which expressed central [CD45RO+/CD62L+: 14±9%] and effector memory markers [CD45RO+/CD62L-: 80±11%] associated with long term in vivo persistence. The expanded lines recognized the targeted antigens WT1, PRAME and Survivin by IFNg ELIspot with activity against >1 targeted antigens in all cases. None of the lines reacted against non-malignant patient-derived cells (4±3% specific lysis; E: T 20:1) - a study release criterion. Thus far we have treated 8 high risk ALL patients with donor derived TAA T cells post-transplant to prevent disease relapse (Table 1). Infusions were well tolerated with no dose-limiting toxicity, GVHD, CRS or other adverse events. Two patients were not evaluable per study criteria as they received >0.5mg/kg of steroids within 4 weeks of infusion and were replaced. Five of the 6 remaining patients infused remain in CR a median of 11.2 months post-infusion (range 9-22 months). We detected the expansion of tumor-reactive T cells in patient peripheral blood post-infusion against both targeted (WT1, Survivin, PRAME) and non-targeted antigens (SSX2, MAGE-A4, -A1, -A2B, -C1, MART1, AFP and NYESO1) reflecting epitope and antigen spreading. The single patient who relapsed showed no evidence of tumor-directed T cell expansion despite receiving 3 additional infusions at 4 week intervals. Conclusion: In summary, infusion of donor multi-TAA-specific T cells to patients with ALL post allogeneic HSCT is feasible, safe and as evidenced by expansion and antigen spreading in patients, may contribute to disease control. This strategy may present a promising addition to current immunotherapeutic approaches for prophylaxis for leukemic relapse in HSCT recipients. Table 1. Table 1. Disclosures Vera: Marker: Equity Ownership. Heslop:Marker: Equity Ownership; Cytosen: Membership on an entity's Board of Directors or advisory committees; Cell Medica: Research Funding; Gilead Biosciences: Membership on an entity's Board of Directors or advisory committees; Tessa Therapeutics: Research Funding; Viracyte: Equity Ownership. Leen:Marker: Equity Ownership.

scholarly journals First-in-Human, Phase 1/2 Trial to Assess the Safety and Clinical Activity of Subcutaneous GEN3013 (DuoBody®-CD3×CD20) in B-Cell Non-Hodgkin Lymphomas

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 758-758 ◽  
Author(s):  
Pieternella Lugtenburg ◽  
Rogier Mous ◽  
Michael Roost Clausen ◽  
Martine E.D. Chamuleau ◽  
Peter Johnson ◽  
...  
Keyword(s):  
T Cell ◽  
B Cells ◽  
B Cell ◽  
Board Of Directors ◽  
Dose Escalation ◽  
Research Funding ◽  
Clinical Activity ◽  
Employment Equity ◽  
Advisory Committees ◽  
Equity Ownership

Introduction: CD20-specific monoclonal antibodies (mAbs) have demonstrated efficacy in the treatment of B-cell non-Hodgkin lymphomas (B-NHL); however, a significant proportion of patients (pts) present with refractory disease or will experience relapse. GEN3013 (DuoBody®-CD3×CD20) is the first subcutaneously administered IgG1 bispecific antibody (bsAb) that targets the T-cell surface antigen CD3 and the B-cell surface antigen CD20, triggering T-cell-mediated killing of B cells. In vitro, GEN3013 efficiently activates and induces cytotoxic activity of CD4+ and CD8+ T cells in the presence of B cells (Hiemstra et al. Blood 2018), and results in long-lasting depletion of B cells in cynomolgus monkeys. Subcutaneous (SC) GEN3013 in cynomolgus monkeys resulted in lower plasma cytokine levels, and similar bioavailability and B-cell depletion, compared with intravenous administration. GEN3013 has higher potency in vitro than most other CD3×CD20 bsAbs in clinical development (Hiemstra et al. HemaSphere 2019). SC GEN3013 in pts with B-NHL is being evaluated in a first-in-human, Phase 1/2 trial (NCT03625037), which comprises a dose-escalation part and a dose-expansion part. Here we report preliminary dose-escalation data. Methods: Pts with CD20+ B-NHL with relapsed, progressive, or refractory disease following anti-CD20 mAb treatment, and ECOG PS 0-2 were included. During dose escalation, pts received SC GEN3013 flat dose in 28-day cycles (q1w: cycle 1-2; q2w: cycle 3-6; q4w thereafter) until disease progression or unacceptable toxicity. Risk of cytokine release syndrome (CRS) was mitigated with the use of a priming dose and premedication with corticosteroids, antihistamines, and antipyretics. Primary endpoints were adverse events (AEs) and dose-limiting toxicities (DLTs). Secondary endpoints included pharmacokinetics (PK), immunogenicity (anti-drug antibodies [ADA]), pharmacodynamics (PD) (cytokine measures; laboratory parameters), and anti-tumor activity (tumor size reduction; objective and best response). Results: At data cut-off (June 28, 2019), 18 pts were enrolled into the dose-escalation part of the trial, with safety data available for pts receiving doses starting at 4 µg. Most pts had diffuse large B-cell lymphoma (DLBCL; n=14) and were heavily pre-treated; 10 pts had received ≥3 prior lines of therapy (overall median [range]: 3 [1-11]). The median age was 58.5 years (range: 21-80), and 13 pts were male. At a median follow-up of 1.9 months, pts received a median of 5 doses (range: 1-14); treatment is ongoing in 6 pts. Twelve pts discontinued treatment due to progressive disease. Six pts died (2 during treatment, 4 during survival follow-up), all due to disease progression and unrelated to treatment. The most common (n≥5) treatment-emergent AEs were pyrexia (n=8), local injection-site reactions (n=7), diarrhea (n=5), fatigue (n=5), and increased aspartate aminotransferase (n=5). The most common Grade (G) 3/4 AEs were anemia (n=3) and neutropenia (n=3). Despite increasing GEN3013 doses, all CRS events were non-severe (initial observation: 3/8 pts, G1: n=1, G2: n=2; following modification of premedication plan [corticosteroids for 3 days]: 6/10 pts, G1: n=4, G2: n=2). Increases in peripheral cytokine (IL6, IL8, IL10, IFNγ, TNFα) concentrations after GEN3013 dosing correlated with clinical symptoms of CRS in most pts. No pts had tumor lysis syndrome or neurological symptoms. No DLTs were observed. GEN3013 PK profiles reflect SC dosing; Cmax occurred 2-4 days after dosing. No ADAs were detected. PD effects following GEN3013 dosing were observed at dose levels as low as 40 µg and included rapid, complete depletion of circulating B cells (if present after prior anti-CD20 therapy) and peripheral T-cell activation and expansion. The first evidence of clinical activity was observed at a dose level of 120 µg, with complete metabolic response observed in a pt with DLBCL. Conclusions: Subcutaneously administered GEN3013, a potent CD3×CD20 bsAb, shows good tolerability and early evidence of clinical activity at low dose levels in heavily pretreated pts with relapsed or refractory B-NHL. All CRS events were non-severe and did not lead to discontinuation. No DLTs were observed. Dose escalation is ongoing; updated data will be presented. Dose expansion will begin upon determining the recommended Phase 2 dose (RP2D) (NCT03625037). Disclosures Lugtenburg: Janssen Cilag: Honoraria; Roche: Consultancy, Honoraria, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria; Servier: Consultancy, Honoraria, Research Funding; Genmab: Consultancy, Honoraria; BMS: Consultancy; Takeda: Consultancy, Honoraria, Research Funding. Mous:Bristol-Myers Squibb: Honoraria; Celgene: Honoraria; Sandoz: Honoraria; Roche: Honoraria; Abbvie: Honoraria; Takeda: Honoraria, Research Funding; Janssen Cilag: Consultancy, Honoraria; MSD: Honoraria; Gilead: Consultancy, Honoraria, Research Funding. Clausen:Abbvie: Other: Travel grant to attend ASH 2019. Johnson:Boehringer Ingelheim: Honoraria; Janssen: Consultancy, Honoraria, Research Funding; Celgene: Honoraria; Epizyme: Honoraria, Research Funding; Incyte: Honoraria; Takeda: Honoraria; Genmab: Honoraria; Bristol-Myers Squibb: Honoraria; Kite: Honoraria; Novartis: Honoraria. Rule:Janssen: Consultancy, Honoraria, Research Funding; Roche: Consultancy, Honoraria, Research Funding; Astra-Zeneca: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; Pharmacyclics: Consultancy, Honoraria; Gilead: Consultancy, Honoraria; Sunesis: Consultancy, Honoraria; TG Therapeutics: Consultancy, Honoraria; Napp: Consultancy; Kite: Consultancy. Oliveri:Genmab: Employment, Equity Ownership. DeMarco:Genmab: Employment, Equity Ownership. Hiemstra:Genmab: Employment, Equity Ownership, Other: Warrants. Chen:Genmab: Employment. Azaryan:Genmab: Employment. Gupta:Genmab: Employment, Equity Ownership. Ahmadi:Genmab Inc: Employment, Other: stock and/or warrants. Hutchings:Incyte: Research Funding; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Research Funding; Genmab: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Research Funding; Janssen: Research Funding; Pfizer: Research Funding.

scholarly journals Development of Novel Second Generation DC/Tumor Fusion Vaccine in Lymphoma

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 392-392 ◽  
Author(s):  
Shira Orr ◽  
Marzia Capelletti ◽  
Haider Ghiasuddin ◽  
Dina Stroopinsky ◽  
Jessica Liegel ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Board Of Directors ◽  
Tumor Cells ◽  
Research Funding ◽  
Second Generation ◽  
Advisory Board ◽  
Advisory Committees ◽  
Equity Ownership ◽  
Cells Cultured

Introduction: We have pioneered a personalized cancer vaccine in which patient derived tumor cells are fused with autologous dendritic cells (DCs) such that a broad array of shared and neo-tumor antigens is presented in the context of DC mediated co-stimulation, limiting the risk of antigen escape. In clinical trials of patients with hematologic malignancies, vaccination with DC/tumor fusions induced an expansion of tumor-specific T cells, and resulted in prolonged remissions in a subset of patients. In the current study, we have developed a novel second generation vaccine, whereby a DC/lymphoma fusion vaccine is presented in the context of a unique biomatrix that expresses high levels of the 41BB costimulatory molecule, to further accentuate T cell activation and prevent the establishment of tumor tolerance. In this study, we demonstrate efficacy of DC/lymphoma fusion cell vaccination in a preclinical lymphoma model, and show enhanced potency of the second-generation vaccine. Methods/Results: We first demonstrated the potency of the DC/tumor fusion vaccine in generating anti-tumor immunity in the A20 lymphoma model. Murine DC/A20 fusions were generated from bone marrow derived mononuclear cells cultured with GM-CSF and IL-4 then fused to syngeneic A20 lymphoma cells. DC/A20 fusion cells effectively induced tumor specific immunity as manifested by potent lysis of A20 T cells in vitro as compared to unstimulated T cells in a standard CTL assay. Consistent with this observation, vaccination with DC/A20 fusions effectively induced lymphoma specific immunity in an immunocompetent murine model. Balb/C mice (30 animals) underwent IV inoculation with 750,000 syngeneic, luciferase and mCherry transduced, A20 cells. 24 hours after tumor cells challenge, 15 mice were treated subcutaneously with 105 DC/A20 fusions. Tumor burden was detected using BLI imaging. 10 days post inoculation, within the untreated cohort all 15/15 mice had detectable tumor whereas within the treated group, 5 mice did not demonstrate any evidence of disease and 5 mice demonstrated minimal disease. We subsequently demonstrated that patient derived autologous DC/lymphoma fusions stimulated T cell mediated lysis of primary lymphoma cells. DC were generated from patient derived peripheral blood mononuclear cells cultured with GM-CSF and IL-4 and matured with TNFa. Primary lymphoma cells were isolated from resected tumor and fused with DC at a ratio of 10:1. Fusion stimulated T cells potently lysed autologous tumor cells as compared to unstimulated T cells (25.7% as compared to 12.66%) in a standard CTL assay. To further enhance vaccine potency, we developed a biomatrix substrate expressing the costimulatory molecule 41BB. Using carbodiimide chemistry we covalently bonded RGD peptide and 41BBL protein to an alginate (Alg)-based scaffold. The Alg/RGD/41BBL scaffold can serve as a supporting microenvironment for the co-culture of T cells and fusion vaccine. We cultured syngeneic T cells with DC/A20 fusion vaccine within a scaffold with or without bound 41BBL and examined the T cells cytotoxicity by a CTL assay as described above. Vaccine mediated stimulation of T cells in the context of the Alg/RGD/41BBL scaffold demonstrated higher levels of tumor lysis as compared to the percent T cells cultured within an Alg/RGD scaffold (22.95% and 13.95% respectively). Conclusion: In the current study we assessed the efficacy of the DC/Lymphoma fusion vaccine to elicit a tumor specific immune response. We succeeded in demonstrating the capacity of DC/Lymphoma fusion vaccine to generate tumor specific T cell cytotoxicity in vitro as well as in vivo in an immunocompetent murine model. Accordingly, we presented patient derived primary tumor results supporting the applicable nature of the DC/Lymphoma vaccine in lymphoma patients. In addition, we developed a second-generation fusion vaccine comprised of the original DC/Tumor vaccine presented to the T cells in an Alg/RGD/41BBL scaffold acting as a nurturing microenvironment for T cell immune specific response against the tumor cells. Our initial results exhibit promising potential and an in vivo experiment with the second-generation fusion vaccine is ongoing. Disclosures Arnason: Celgene/Juno: Consultancy; Regeneron Pharmaceuticals, Inc.: Consultancy. Kufe:Nanogen Therapeutics: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Genus Oncology: Equity Ownership; Reata Pharmaceuticals: Consultancy, Equity Ownership, Honoraria; Hillstream BioPharma: Equity Ownership; Victa BioTherapeutics: Consultancy, Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees; Canbas: Consultancy, Honoraria. Rosenblatt:Dava Oncology: Other: Education; BMS: Research Funding; Partner Tx: Other: Advisory Board; Merck: Other: Advisory Board; Parexel: Consultancy; Imaging Endpoint: Consultancy; Celgene: Research Funding; BMS: Other: Advisory Board ; Amgen: Other: Advisory Board. Avigan:Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Pharmacyclics: Research Funding; Juno: Membership on an entity's Board of Directors or advisory committees; Partners Tx: Membership on an entity's Board of Directors or advisory committees; Partner Tx: Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Bristol-Myers Squibb: Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy; Parexel: Consultancy; Takeda: Consultancy.

scholarly journals Comparative Efficacy Among 3rd Line Post-Imatinib Chronic Phase-Chronic Myeloid Leukemia (CP-CML) Patients after Failure of Dasatinib or Nilotinib Tyrosine Kinase Inhibitors

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 4551-4551 ◽  
Author(s):  
Jeffrey H. Lipton ◽  
Dhvani Shah ◽  
Vanita Tongbram ◽  
Manpreet K Sidhu ◽  
Hui Huang ◽  
...  
Keyword(s):  
Chronic Myeloid Leukemia ◽  
Board Of Directors ◽  
Myeloid Leukemia ◽  
Research Funding ◽  
Kinase Inhibitors ◽  
Cytogenetic Response ◽  
Comparative Efficacy ◽  
Employment Equity ◽  
Advisory Committees ◽  
Equity Ownership

Abstract INTRODUCTION Patients with chronic myeloid leukemia (CP-CML) failing 1st line imatinib are most commonly treated with the second-generation (2G) tyrosine kinase inhibitors (TKIs) dasatinib and nilotinib. However, for patients who experience resistance or intolerance (R/I) to 2G-TKIs in 2nd line, there currently is no consensus on the optimal therapy sequence for 3rd line treatment. The comparative efficacy of using ponatinib in the 3rd line after 2G TKI failure was examined in a previous study (Lipton et al., ASH 2013). This study assesses the comparative efficacy of ponatinib versus sequential treatment of alternate 2G TKIs in 3rdline setting in two separate patient populations, post-imatinib and dasatinib patients and post-imatinib and nilotinib patients. METHODS A systematic review was conducted in MEDLINE, EMBASE and the Cochrane Libraries (2002-2014), as well as 3 conferences (ASH (2008-2014), ASCO (2008-2014), and EHA (2008-2013)). Studies evaluating any TKI were included if they enrolled 10 or more post-imatinib adult patients with CP-CML who were also R/I to dasatinib or nilotinib. All study designs were considered and no restriction was applied with respect to therapy dose, due to incomplete reporting of doses in the available studies. Analyses was run on two groups of patients, those failing imatinib and dasatinib (Group Ima/Das) and those failing imatinib and nilotinib (Group Ima/Nil). Bayesian methods were used to synthesize major cytogenetic response (MCyR) and complete cytogenetic response (CCyR) from individual studies and estimate the overall response probability with 95% credible interval (CrI) for each treatment. Bayesian analysis also was used to estimate the likelihood that each treatment offers the highest probability of CCyR/MCyR based on available evidence. RESULTS Six studies evaluating bosutinib, nilotinib and ponatinib for Group Ima/Das (n= 419) and five studies evaluating bosutinib, dasatinib and ponatinib for Group Ima/Nil (n=83) were included in the analysis. All studies reported CCyR in both groups. Five studies evaluating bosutinib, nilotinib and ponatinib reported MCyR in Group Ima/Das and three studies evaluating bosutinib and ponatinib reported MCyR in Group Ima/Nil. Synthesized treatment-specific probabilities and 95% CrI for CCyR are presented in Figure 1. Synthesized treatment-specific probabilities of CCyR for Group Ima/Das were 27% for nilotinib, 20% for bosutinib and 54% (95% CrI 43%% to 66%) for ponatinib. Treatment-specific probabilities of MCyR for Group Ima/Das were 41% for nilotinib, 28% for bosutinib and 66% (95% CrI 55%% to 77%) for ponatinib. The probability of ponatinib providing superior response to all other included treatments for group Ima/Das was estimated to be >99% for both CCyR and MCyR. Synthesized treatment-specific probabilities of CCyR for Group Ima/Nil were 25% for dasatinib, 26% for bosutinib and 67% (95% CrI 51%% to 81%) for ponatinib. Treatment-specific probabilities of MCyR for Group Ima/Nil were 33% for bosutinib and 75% (95% CrI 60%% to 87%) for ponatinib. The probability of ponatinib providing superior response to all other included treatments for group Ima/Nil was estimated to be >99% for both CCyR and MCyR. CONCLUSIONS The post imatinib and dasatinib group included more studies with larger sample sizes compared with the post imatinib and nilotinib group. Overall, response rates appear higher for TKIs in the post imatinib and nilotinib group compared with the post imatinib and dasatinib group. For both groups, patients on ponatinib had higher CCyR and MCyR rates compared with the sequential 2G TKIs included in this analysis. Based on available data, ponatinib appears to provide a higher probability of treatment response for patients failing imatinib and dasatinib/ nilotinib compared with sequential 2G TKI therapy commonly used in this indication. Figure 1 Figure 1. Disclosures Lipton: Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Bristol Myers: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Ariad: Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Shah:Ariad Pharmaceuticals: Research Funding. Tongbram:Ariad Pharmaceuticals: Research Funding. Sidhu:Ariad Pharmaceuticals Inc.: Research Funding. Huang:ARIAD Pharmaceuticals, Inc.: Employment, Equity Ownership. McGarry:ARIAD Pharmaceutical, Inc.: Employment, Equity Ownership. Lustgarten:ARIAD Pharmaceuticals Inc: Employment, Equity Ownership. Hawkins:Ariad Pharmaceuticals Inc.: Research Funding.

scholarly journals Identification of Small Molecule Kinase Inhibitors That Potently and Reversibly Block Chimeric Antigen Receptor T Cell Proliferation and Cytotoxicity

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 2068-2068
Author(s):  
Parmeshwar Amatya ◽  
Matthew L. Cooper ◽  
Alun J Carter ◽  
John F. DiPersio
Keyword(s):  
T Cell ◽  
Research Funding ◽  
Kinase Inhibitors ◽  
Kinase Inhibitor ◽  
Advisory Committees ◽  
Car T Cell ◽  
Car T ◽  
Life Threatening ◽  
Equity Ownership

Introduction: Despite remarkable clinical efficacy, CAR-T therapy has been limited by life threatening toxicities in over 30% of patients.1, 2 Toxicities primarily manifest as cytokine release syndrome (CRS) characterized by an early phase with fever, hypotension and elevations of cytokines including IFNγ, GM-CSF, TNF, IL-10, and IL-6 and a later phase associated with life-threatening or life-ending neurologic events. We hypothesized that reversible inhibition of CAR mediated signaling will enable controllable regulation of CAR-T cell activity in vivo and mitigate CAR-T mediated toxicities. There are specific protein kinases such as the SRC kinases, LCK, and ZAP-70 that are known to be involved in various cellular signaling pathways, especially T cell receptor mediated signaling and may also be appropriate targets for modulating (both enhancing and inhibiting) CAR-T function in a rapid and reversible fashion in vivo. Our hypothesis is that small molecule inhibitors of TCR signaling and downstream pathways could be identified using specific high throughput screens. Methods: To identify novel inhibitors of CAR-T cell proliferation, we developed a high throughput kinase inhibitor screen to identify compounds that reversibly inhibit CAR-T function. T cells containing a third generation CAR targeting CD19 cells (CAR19) and CD19+ tumor cells (Ramos cells expressing both GFP and luciferase) were incubated at an effector to target ratio of 1:1 in 96 well plates in the presence of 1µM of each inhibitor. After 24 hours, tumor cell death induced by CAR-T was measured using bioluminescence (BLI) imaging. Small molecules that inhibited CAR-T proliferation and cytotoxicity were determined by assessing the BLI signal in each well. Results: A protein kinase inhibitor library (Selleckchem, Texas) containing 644 independent compounds was tested (Figure 1). Of the 644 kinase inhibitors tested, 32 were found to be potent inhibitors of CART19 cell activation and cytotoxic killing of CD19+ target tumor cells, reducing anti-tumor viability in 24 hours by >50% compared to vehicle control. Compounds such as Nintedanib (C3), Dasatinib (C9), and Saracatinib (C12), all SRC kinase inhibitors, were able to inhibit cell killing by 99%, 84%, and 76% respectively. Next we assessed the reversibility of CAR-T cell mediated killing upon removal of inhibitors from the cultures. Reinitiation of potent, anti-tumor activity was observed within 24 hours after inhibitor removal, confirming reversible nature of CAR-T cell inhibition by the three most potent compounds. Conclusions: Recent publications (Weber et al Blood Adv, 2018, Westermann et al. Sci Transl Med, 2019) have also shown that dasatinib can reversibly suppresses CAR-T cell cytotoxicity, cytokine secretion, and proliferation in vitro and in vivo. 3, 4 Here we confirm the reports of others regarding dasatinib and that show for the first time that reversible inhibition of CAR-T activity by kinase inhibitors is not limited solely to dasatanib, but is observed with other small molecules targeting many different kinases. This work further demonstrates the potential applications of tyrosine kinase inhibitors as a safety switch to modulate CAR-T cell toxicity. 1. Maude, NEJM 2014 2. Davila, SciTransMed 2014 3. Mestermann SciTransMed 2019 4. Weber. Blood Adv 2019 Disclosures Cooper: Wugen: Consultancy, Equity Ownership, Patents & Royalties. DiPersio:WUGEN: Equity Ownership, Patents & Royalties, Research Funding; Magenta Therapeutics: Equity Ownership; Celgene: Consultancy; Karyopharm Therapeutics: Consultancy; RiverVest Venture Partners Arch Oncology: Consultancy, Membership on an entity's Board of Directors or advisory committees; Cellworks Group, Inc.: Membership on an entity's Board of Directors or advisory committees; NeoImmune Tech: Research Funding; Bioline Rx: Research Funding, Speakers Bureau; Macrogenics: Research Funding, Speakers Bureau; Incyte: Consultancy, Research Funding; Amphivena Therapeutics: Consultancy, Research Funding.

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