Rational design of AAV vectors with human hepatocyte tropism and neutralizing antibody evasion

具有人肝细胞趋向性和中和抗体逃避性的AAV载体的合理设计

基本信息

批准号：
10546241
负责人：
Chengwen Li
金额：
$ 26.11万
依托单位：
BEDROCK THERAPEUTICS, INC.
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-09-01 至 2024-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10546241
关键词：
Affect Albumins American Anatomy Animal Model Animals Binding Biology Blindness Blood Component Removal Canis familiaris Capsid Cells Clinic Clinical Clinical Research Clinical Trials Data Dependovirus Directed Molecular Evolution Disease Dose Engineering FDA approved Flow Cytometry Gene Delivery Gene Transduction Agent Gene Transfer Genetic Diseases Goals Hepatocyte High Prevalence Human Immunize Immunohistochemistry In Vitro Industry Infection Intravenous Immunoglobulins Investigation Libraries Liver Liver diseases Masks Mediating Mendelian disorder Mental Depression Methods Mus Muscular Atrophy Mutation Organ Pathway interactions Patients Pharmaceutical Preparations Pharmacologic Substance Phase Plasma Play Population Preparation Prevalence Price Primates Production Property Quality of life Rare Diseases Research Personnel Role Safety Serotyping Serum Spinal Surface System Technology Therapeutic Time Tissues Traction Tropism Variant Virion Xenograft Model Xenograft procedure adeno-associated viral vector base clinical development cost cross reactivity delivery vehicle efficacy testing experimental study gene therapy humanized mouse mortality mutant neutralizing antibody novel phase 2 study rational design success therapeutic transgene vector virtual

项目摘要

Adeno-associated virus (AAV) vectors have been successfully applied in clinical trials in patients with diverse disorders. Two AAV based gene therapy drugs have been recently approved by the FDA. Luxturna has been valued at $850,000 for a one-time treatment for a rare form of blindness and Zolgensma priced at $2,100,000 for spinal muscle atrophy. As such, AAV vector based gene therapy is an increasingly attractive market. Although successful in clinical studies, two concerns restrict broader AAV vector applications for patients requiring liver targeted AAV gene therapy following systemic administration: low human hepatocyte transduction and neutralizing antibody (Nab)-mediated inhibition of AAV transduction. Several approaches have been explored for AAV transduction enhancement or capsid Nab evasion. Engineering of the AAV capsid presents a very powerful and popular technology that has been extensively studied to develop novel AAV vectors for enhanced transduction in animal models or Nab escape in vitro. However, it has been demonstrated that the results from mouse experiments do not recapitulate those of large animals such as primates and dogs. Thus, the data for AAV variants generated in animal cells and organs may not translate into successful human applications. Recently, a mouse xenograft model with human hepatocytes has been used to develop human liver targeted AAV vectors for gene therapy. In our previous studies, we have successfully isolated several AAV mutants from the liver of chimeric mice with human hepatocyte xenografts in the presence of human Nabs (IVIG) using the AAV shuffled capsid library approach. Specifically, BDRK001 (AAV mutant LP2-10) demonstrated a much higher ability to evade Nabs than any other AAV serotypes or mutants. However, BDRK001 was not enhanced for transduction in human hepatocytes when compared to the best natural serotype. In this application, we will use rational design strategy to generate novel AAV capsids by variable region I (VRI) domain swapping of BDRK001 using natural serotypes or mutants with high human liver tropism. This panel will then be evaluated in chimeric mice for human hepatocyte transduction (Aim 1) and Nab evasion (Aim 2). Bedrock's long-term goal of this approach is low dose AAV gene therapy for the successful treatment of a variety of liver diseases, independent of the patient's Nab prevalence.

腺相关病毒（AAV）载体已成功应用于多种疾病患者的临床试验失调。两种基于 AAV 的基因治疗药物最近已获得 FDA 批准。卢克斯图纳已经用于治疗一种罕见失明的一次性治疗的价值为 850,000 美元，Zolgensma 的价值为 2,100,000 美元用于脊肌萎缩。因此，基于 AAV 载体的基因治疗是一个越来越有吸引力的市场。尽管在临床研究中取得了成功，但有两个问题限制了 AAV 载体在患者中更广泛的应用全身给药后需要肝脏靶向 AAV 基因治疗：人肝细胞水平低转导和中和抗体 (Nab) 介导的 AAV 转导抑制。几种方法已探索 AAV 转导增强或衣壳 Nab 逃避。 AAV 的工程设计衣壳提供了一种非常强大且流行的技术，已被广泛研究以开发新颖的用于增强动物模型转导或体外 Nab 逃逸的 AAV 载体。然而，已经证明小鼠实验的结果并不能概括大型动物的结果，例如灵长类动物和狗。因此，动物细胞和器官中产生的 AAV 变体的数据可能无法转化转化为成功的人类应用。最近，人类肝细胞的小鼠异种移植模型已被建立。用于开发用于基因治疗的人类肝脏靶向 AAV 载体。在我们之前的研究中，我们有成功地从具有人肝细胞异种移植物的嵌合小鼠的肝脏中分离出几种 AAV 突变体使用 AAV 改组衣壳库方法检测人 Nabs (IVIG) 的存在。具体来说，BDRK001 （AAV 突变体 LP2-10）比任何其他 AAV 血清型表现出更高的逃避 Nabs 的能力或突变体。然而，与人肝细胞中的转导相比，BDRK001 并未得到增强。最好的天然血清型。在此应用中，我们将使用合理的设计策略通过以下方式生成新型 AAV 衣壳：使用天然血清型或具有高人类肝脏的突变体对 BDRK001 进行可变区 I (VRI) 结构域交换向性。然后将在嵌合小鼠中评估该组的人肝细胞转导（目标 1）和逃跑（目标 2）。 Bedrock 这种方法的长期目标是低剂量 AAV 基因治疗成功治疗多种肝脏疾病，与患者的 Nab 患病率无关。