A Phase I Clinical Trial Testing Feasibility of Hematopoietic Stem Cell Gene Therapy Using Platelet Factor VIII to Safely Improve Hemostasis for Severe Hemophilia A with Inhibitory Antibodies

I 期临床试验测试使用血小板因子 VIII 的造血干细胞基因治疗通过抑制性抗体安全改善严重甲型血友病止血的可行性

• 批准号: 9908183
• 负责人: Parameswaran N Hari
• 金额: $ 159.62万
• 依托单位: MEDICAL COLLEGE OF WISCONSIN
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-04-05 至 2024-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9908183
• 关键词: Address; Affect; Alpha Granule; Animal Model; Animals; Antibodies; Autologous; Autologous Transplantation; Biological; Biological Assay; Blood; Blood Coagulation Disorders; Blood Platelets; Blood Vessels; Bone Marrow; Bypass; CD34 gene; Candidate Disease Gene; Canis familiaris; Capsid Proteins; Cell Survival; Cells; Chronic; Clinical; Clinical Trials; Coagulation Factor Deficiency; Continuous Infusion; DNA; Development; Ectopic Expression; Endothelial Cells; Engineering; Engraftment; Ensure; F8 gene; Factor VIII; Gene Transfer; Generations; Genes; Genetic Engineering; Genetic Transcription; Genome; HIV; Harvest; Health; Hematopoietic Stem Cell Transplantation; Hematopoietic stem cells; Hemophilia A; Hemorrhage; Hemostatic function; Hepatitis C; Human; Human Engineering; Immune; Immune response; Immune system; Immunosuppression; In Vitro; Individual; Infusion procedures; Inherited; Intravenous; Intravenous infusion procedures; Isoantibodies; Lead; Lentivirus Vector; Liver; Mediating; Megakaryocytes; Methods; Modeling; Molecular Genetics; Monitor; Morbidity - disease rate; Mus; Mutation; Nature; Odds Ratio; Other Genetics; Patients; Peripheral Blood Stem Cell; Phase I Clinical Trials; Plasma; Plasma Proteins; Prophylactic treatment; Proteins; Protocols documentation; Public Health; Recombinants; Recurrence; Regimen; Reporting; Resources; Reverse Transcriptase Polymerase Chain Reaction; Risk; Safety; Site; Source; Testing; Time; Tissues; Transcriptional Regulation; Transplantation; Transplantation Conditioning; Viral; X Chromosome; adeno-associated viral vector; cellular transduction; clinically significant; conditioning; conventional therapy; cost; enzyme replacement therapy; first-in-human; gene replacement therapy; gene therapy; gene transfer vector; human study; immunogenic; improved; inhibitor/antagonist; intravenous administration; joint injury; liver injury; meetings; mortality; mouse model; neutralizing antibody; novel; novel strategies; patient population; preclinical study; prevent; promoter; prophylactic; release factor; repaired; response; safety and feasibility; safety testing; standard care; success; transduction efficiency; vascular injury; vector; viral transmission

PROJECT SUMMARY/ABSTRACT Patients with severe hemophilia A (PWHA) have a significant deficiency (<1% normal) in coagulation factor VIII (FVIII) that frequently causes recurrent spontaneous bleeding episodes leading to significant morbidity and mortality. Conventional therapy for HA employing the infusion of donor plasma FVIII cryoprecipitate product can be complicated by blood-borne transmission of viral illnesses (including HIV & hepatitis C). Use of recombinant FVIII (rFVIII) products has largely replaced the use of human-derived FVIII (because rFVIII prevents risk of viral transmission); however, plasma FVIII remains a valuable resource for HA throughout the world. Prophylactic therapy with FVIII requires the intravenous administration of FVIII 2-3 times weekly throughout a patient's lifetime. Unfortunately, recurrent intravenous access, low compliance, break-through bleeding, and joint-damage can occur despite FVIII prophylaxis. Additionally, ≈30% of HA develop allo-antibodies to FVIII replacement products that inhibit its ability to restore hemostasis. Thus, treatment of bleeding in these patients involves the administration of a costly “bypass” agent therapy (i.e., FVIII with immune suppression and/or FVIIa). Success has been achieved by inducing immune tolerization to FVIII in ≈60% of HA with inhibitory antibodies by several rigorous infusions of FVIII (often in the setting of prophylaxis with bypassing agents) although treatment for FVIII inhibitors remains a critical issue for HA patients. Due to its monogenic nature, HA is an ideal candidate for gene replacement therapy with the potential for correction of HA. Promising approaches include the targeted expression of human FVIII to the liver by intravenous infusion of naked DNA, the generation of a novel adeno-associated viral (AAV) vector equipped with less immunogenic coat proteins, and vectors incorporating small active forms of FVIII (that conform to the 4.4 kb packaging capacity of AAV). However, these strategies exclude individuals with 1) inhibitory antibodies to FVIII (≈30% PWHA), 2) pre-existing antibodies to the AAV (≈40% humans) and 3) chronic liver damage. To address this problem of considerable clinical significance, we propose a first-in-human phase I clinical trial employing a hematopoietic stem cell (HSC) gene therapy strategy that utilizes a lentiviral gene transfer vector encoding human FVIII under the transcriptional control of the megakaryocyte-specific ITGA2B gene promoter that targets expression of the FVIII gene in megakaryocytes causing ectopic synthesis, storage and regulated-release of factor VIII from α-granules of activated platelets precisely at the site of vascular injury. This proposal is supported by pre-clinical studies that showed platelet FVIII safely and efficiently improved hemostasis in murine and canine models of HA without the development of inhibitory antibodies to FVIII and even in the presence of pre-existing inhibitory antibodies to FVIII in mice. In summary, the proposed trial should reduce the risk of severe bleeding in PWHA with inhibitory antibodies to FVIII for whom current strategies employing factor bypassing agents, tolerizing therapy, and other genetic therapies are inadequate. 1

项目摘要/摘要 严重的血友病A（PWHA）患者的凝血因子显着缺陷（<1％） VIII（FVIII）经常引起复发的赞助商出血发作，导致明显的发病率和 死亡。 HA采用供体等离子体FVIII冷冻沉淀产品的常规疗法 血传播病毒疾病（包括HIV和肝炎）可能会使人复杂化。使用 重组FVIII（RFVIII）产品已在很大程度上取代了人类衍生的FVIII（因为RFVIII 防止病毒传播的风险）；但是，血浆FVIII仍然是HA的宝贵资源 世界。 FVIII的预防性治疗需要静脉注射FVIII每周2-3次 通过患者的一生。不幸的是，经常出现的静脉注射，低依从性，突破性 尽管进行了FVIII预防，也可能发生出血和关节损伤。此外，HA开发的约30％ 对FVIII替代产物的同种抗体抑制其恢复止血的能力。那，处理 这些患者的出血涉及给予昂贵的“旁路”药物治疗（即FVIII 免疫抑制和/或FVIIA）。通过诱导对FVIII的免疫耐受性实现了成功 FVIII严格输注的抑制性抗体的HA占HA的约60％（通常在预防的情况下 通过旁路剂）尽管对HA患者的FVIII抑制剂进行治疗仍然是一个关键问题。 由于其单基质性质，HA是基因替代疗法的理想候选者，具有潜力 校正HA。有希望的方法包括人类FVIII对肝脏的靶向表达 赤裸裸的DNA静脉输注，这是一种新型腺相关病毒（AAV）载体的产生 具有较少的免疫原性外套蛋白，以及编码小型活性FVIII的载体（符合符合 AAV的4.4 kb包装能力）。但是，这些策略排除了1）抑制性抗体的个体 到FVIII（≈30％PWHA），2）对AAV的抗体（≈40％人类）和3）慢性肝损害。 为了解决这个相当大的临床意义的问题，我们提出了第一阶段I期临床试验 采用使用慢病毒基因转移载体的造血干细胞（HSC）基因治疗策略 在巨核细胞特异性ITGA2B基因启动子的转录控制下编码人FVIII 这是针对巨核细胞中FVIII基因的表达，导致生态合成，储存和 从血管损伤部位正好在活化血小板的α颗粒中调节了VIII的释放。 该建议得到了临床前研究的支持，该研究表明血小板FVIII安全有效地改进了 HA的鼠和犬模型中的止血，而没有发展为FVIII和FVIII和的抑制性抗体 即使存在于小鼠FVIII的抑制性抗体。总之，拟议的审判 应降低PWHA严重出血的风险 使用因子绕过药物，容忍治疗和其他基因疗法的策略不足。 1