Project 2: Anti-PR1 Immune Therapy for Myeloid Leukemia

项目2：髓系白血病的抗PR1免疫治疗

• 批准号: 10247505
• 负责人: JEFFREY J MOLLDREM
• 金额: $ 27.24万
• 依托单位: UNIVERSITY OF TX MD ANDERSON CAN CTR
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-08-05 至 2023-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10247505
• 关键词: Action Potentials; Acute Myelocytic Leukemia; Address; Adoptive Cell Transfers; Affinity; Agreement; Allogenic; Animal Model; Antibodies; Antibody Therapy; Antigen Targeting; Antigen-Presenting Cells; Antigens; Apoptosis; Avidity; B-Lymphocytes; Biological Assay; Bispecific Antibodies; Blood; Bone Marrow Cells; Cancer Center; Caring; Cells; Clinic; Clinical; Clinical Research; Clinical Trials; Companions; Complex; Cross Presentation; Cytotoxic T-Lymphocytes; Dendritic Cells; Development; Disease remission; Disease-Free Survival; Doctor of Medicine; Dose; Dose-Limiting; Down-Regulation; Drug Kinetics; Drug resistance; Enrollment; Frequencies; Goals; Grant; HLA-A2 Antigen; Hematopoietic; Hematopoietic stem cells; Human; IgG1; Immune Tolerance; Immune response; Immunoglobulin Idiotypes; Immunotherapeutic agent; Immunotherapy; In Vitro; Industry; Knowledge; Leukocyte Elastase; Maximum Tolerated Dose; Measures; Mediating; Methodology; Modality; Modification; Molecular; Monkeys; Monoclonal Antibodies; Morbidity - disease rate; Myeloid Leukemia; Patients; Peptide Hydrolases; Peptides; Pharmaceutical Preparations; Phase; Phase 1/1b Clinical Trial; Pre-Clinical Model; Predisposition; Proteinase 3; Refractory; Relapse; Resistance; Safety; Source; Specificity; Stem cell transplant; Surface Antigens; T-Cell Receptor; T-Lymphocyte; Testing; Texas; Therapeutic; Time; Toxic effect; Translating; Umbilical Cord Blood; Universities; Vaccination; Vaccines; Work; alpha-beta T-Cell Receptor; alternative treatment; antibody test; base; bi-specific T cell engager; chemotherapy; chimeric antigen receptor T cells; effective therapy; first-in-human; improved; in vivo; incomplete Freund' s adjuvant; leukemia; leukemia relapse; leukemic stem cell; multicatalytic endopeptidase complex; novel; novel strategies; novel therapeutic intervention; overexpression; patient derived xenograft model; phase I trial; pre-clinical; resistance mechanism; response; safety study; targeted treatment; therapy resistant; treatment strategy; tumor; vaccine trial; validation studies

Project Summary Our long-term goal is to develop immune therapies that target aberrantly expressed proteases in blasts and leukemia stem cells. PR1 peptide (VLQELNVTV) is a peptide derived from the leukemia-associated antigens proteinase 3 (P3) and neutrophil elastase (NE), which is presented on HLA-A2 to PR1-specific cytotoxic T lymphocytes (PR1-CTL). During the last grant period, we showed that PR1 is cross-presented by dendritic cells (DCs) and B cells, and we showed the mechanism required proteasome cleavage exogenous P3 and NE taken up by antigen-presenting cells. In previous years of the SPORE grant, we conducted a Phase I-II PR1 vaccine trial in 66 patients with AML, CML, and MDS, and observed immune responses to PR1 vaccine in 58%. However, objective clinical responses were observed in only 11 (16%) patients, and these were limited to patients with low leukemia burden (<10% blasts). We showed that, although highly cytolytic PR1-CTL that expressed high avidity T cell receptors (TCR-αβ) for PR1/HLA-A2 increased after PR1 vaccination in some patients, they underwent apoptosis by leukemia that expressed high PR1/HLA-A2 surface antigen, resulting in immune tolerance by deletion of high avidity PR1-CTL. Furthermore, although high avidity PR1-CTL could be isolated from umbilical cord blood (CB) units, they are difficult to expand in sufficient quantity ex vivo to be useful as an adoptive cell therapy, thus limiting their therapeutic potential. Therefore, in a novel alternative treatment approach to target PR1, we produced a TCR-like monoclonal antibody (8F4) against PR1/HLA-A2. We have produced a humanized 8F4 (h8F4) with high affinity (KD=7.8 nM) to PR1/HLA-A2 and we showed that h8F4 eliminated AML and leukemia stem cells but not normal human hematopoietic stem cells in preclinical models. With an agreement from industry that supported manufacturing of h8F4, we have produced sufficient clinical grade h8F4, showed it mediated ADCC and apoptosis of AML and LSC in vitro and in vivo, and developed companion assays for PK, anti-idiotype and anti-drug antibody testing. Moreover, we have established PDX models of AML for parallel studies to support a clinical trial. Thus, the goals of this proposal are to (1) translate the discovery of this novel h8F4 monoclonal antibody to the clinic in a first-in-human phase I trial in AML; (2) to determine pharmacokinetics, toxicity, and mode of action; and to characterize the mechanism of action, potential resistance mechanisms and to test novel strategies with an h8F4-based bispecific antibody and an h8F4 chimeric antigen receptor (CAR) T cells to increase the potency of 8F4 to overcome potential treatment resistance.

项目摘要 我们的长期目标是开发针对原始细胞中异常表达的蛋白酶的免疫疗法， 白血病干细胞PR 1肽（VLQELNVTV）是来源于白血病相关抗原的肽 蛋白酶3（P3）和中性粒细胞弹性蛋白酶（NE），其存在于HLA-A2上，以PR 1特异性细胞毒性T细胞 淋巴细胞（PR 1-CTL）。在上一个研究期间，我们发现PR 1是由树突状细胞交叉呈递的。 (DCs)和B细胞，我们表明，该机制需要蛋白酶体切割外源性P3和NE采取 由抗原呈递细胞分泌在过去几年的SPORE赠款中，我们进行了第一阶段-第二阶段PR 1疫苗 在66名AML、CML和MDS患者中进行的试验中，观察到58%的患者对PR 1疫苗产生了免疫应答。然而，在这方面， 仅在11例（16%）患者中观察到客观临床反应，这些患者仅限于低血糖患者。 白血病负荷（<10%原始细胞）。我们发现，尽管表达高亲合力的PR 1-CTL具有高度的细胞溶解性， 在一些患者中，PR 1/HLA-A2的T细胞受体（TCR-αβ）在PR 1疫苗接种后增加，他们接受了 表达高PR 1/HLA-A2表面抗原的白血病细胞凋亡，导致免疫耐受， 高亲合力PR 1-CTL的缺失。此外，虽然高亲和力的PR 1-CTL可以从脐带血中分离， 脐带血（CB）单位，它们难以离体扩增足够的量以用作过继细胞 治疗，从而限制其治疗潜力。因此，在一种新的替代治疗方法中， 针对PR 1，我们制备了抗PR 1/HLA-A2的TCR样单克隆抗体（8 F4）。我们创造了一个人性化的 8 F4（h8 F4）对PR 1/HLA-A2具有高亲和力（KD=7.8 nM），我们表明h8 F4消除AML， 白血病干细胞，而不是正常的人造血干细胞的临床前模型。的协议 从支持h8 F4生产的行业来看，我们已经生产了足够的临床级h8 F4， 介导的ADCC和AML和LSC的细胞凋亡，并开发了PK的伴随测定， 抗独特型和抗药抗体检测。此外，我们还建立了AML的PDX模型， 支持临床试验的研究。因此，本提案的目标是（1）翻译这部小说的发现 h8 F4单克隆抗体在AML的首次人体I期试验中用于临床;（2）为了确定药代动力学， 毒性和作用方式;并描述作用机制、潜在耐药机制和 为了测试使用基于h8 F4的双特异性抗体和h8 F4嵌合抗原受体（CAR）T的新策略， 细胞以增加8 F4克服潜在治疗抗性的效力。