Chemical approaches for generating blood-brain barrier-permeable antibody conjugates

生成血脑屏障渗透性抗体缀合物的化学方法

基本信息

批准号：
10455543
负责人：
Kyoji Tsuchikama
金额：
$ 39万
依托单位：
UNIVERSITY OF TEXAS HLTH SCI CTR HOUSTON
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-09-05 至 2025-07-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10455543
关键词：
Antibodies Antibody-drug conjugates Area Attenuated Biodistribution Blood - brain barrier anatomy Blood Circulation Brain Brain Diseases Brain Neoplasms Cell Line Cells Central Nervous System Diseases Chemicals Clinical Clinical Research Disease Drug Delivery Systems Drug Kinetics Drug usage Extravasation Foundations Glioblastoma In Vitro Kinetics Lead Malignant neoplasm of brain Measurable Mediating Modality Molecular Monoclonal Antibodies Mus Newly Diagnosed Patients Peptides Pharmaceutical Preparations Plasma Property Safety Site Specificity Structure Systemic Therapy Technology Therapeutic Therapeutic Monoclonal Antibodies Treatment Efficacy Variant Xenograft procedure antibody conjugate base blood-brain barrier penetration blood-brain barrier permeabilization brain parenchyma chemotherapeutic agent design drug development effective therapy epidermal growth factor receptor VIII immunogenicity improved in vivo intravital fluorescence microscopy mouse model novel novel therapeutics patient derived xenograft model peptide structure phase 3 study receptor stoichiometry transcytosis tumor

项目摘要

1. ABSTRACT The blood-brain barrier (BBB) restricts the influx of biomolecules from the vasculature to the brain parenchyma. This attenuates exposure levels of the brain to systemically administered drugs, especially large- size molecules such as antibodies. This issue also makes systemic treatment of glioblastoma (GBM), the most devastating brain cancer, ineffective in most cases. Recent clinical studies have demonstrated that a measurable number of GBM cells, in particular cells near the growing edge of the infiltrative tumor area, exist behind an intact BBB. Collectively, the features of the BBB create a special challenge for effective treatment of central nervous system (CNS) diseases, including brain cancer, using drugs that have proven efficacy in other diseases. Antibody-drug conjugates (ADCs) are an emerging drug class with prominent target specificity, durable therapeutic efficacy, and high translatability in drug development. While promising, clinical benefits of ADCs in the treatment of brain diseases, in particular GBM, remain unconfirmed. Unfortunately, recent interim analysis in a Phase 3 study using the anti-EGFRvIII ADC Depatux-M (formerly called ABT-414) revealed no survival benefit for patients with newly diagnosed GBM receiving this ADC. Thus, improvement in BBB penetrability for ADCs is critically needed to advance this promising molecular format toward truly effective and safe systemic therapy for CNS diseases. We have developed novel ADC linker technologies, including: 1) branched linkers for site-specific and simultaneous installation of two distinct molecules onto a single antibody and 2) enzymatically cleavable linkers with exceptional circulation stability. Using these technologies, we have successfully constructed homogeneous conjugates appended with peptides that facilitate traversing the BBB through receptor-mediated transcytosis. One of the homogeneous peptide conjugates, as compared to a conventional heterogeneous variant, showed greater accumulation into the brain parenchyma in healthy mice (2.7-fold) and orthotopic GBM tumors in a xenograft mouse model (3.6-fold). Based on these findings, we hypothesize that homogeneous conjugation of properly designed BBB-penetrating peptides with ADCs will be a promising approach for systemic drug delivery to the brain. In this project, we will prepare a variety of BBB-penetrating peptides and construct antibody conjugates with various conjugation modalities (linker attachment site, linker structure, and stoichiometry of the peptides and payloads). All conjugates will be evaluated in vitro and in vivo for plasma stability, receptor-mediated transcytosis efficiency, pharmacokinetics, biodistribution, tolerability, and immunogenicity profiles. We will then evaluate a panel of BBB-permeable ADCs for tumor targeting efficiency as well as therapeutic efficacy in cell line-based and patient-derived xenograft mouse models of orthotopic GBM. We will also perform intravital fluorescence microscopy to evaluate kinetics and dynamics of extravasation in both healthy and tumor-bearing mouse models. Successful completion of this project will clarify the effect of the peptide structure and conjugation modality on BBB penetrability of antibody conjugates as well as other drug properties. We also expect to identify rational molecular design to unleash the full therapeutic potential of monoclonal antibodies and ADCs for brain targeting, which may ultimately lead to novel drug development strategies toward a cure for difficult-to-treat CNS diseases, such as GBM.

1. 摘要血脑屏障 (BBB) 限制生物分子从脉管系统流入大脑薄壁组织。这减弱了大脑对全身给药的药物的暴露水平，尤其是大剂量的药物。大小分子，例如抗体。这个问题也使得胶质母细胞瘤（GBM）的系统治疗成为最重要的治疗方法。毁灭性的脑癌，在大多数情况下无效。最近的临床研究表明，存在可测量数量的 GBM 细胞，特别是浸润性肿瘤区域生长边缘附近的细胞在完整的 BBB 后面。总的来说，BBB 的特征对有效治疗中枢神经系统 (CNS) 疾病，包括脑癌，使用已被证明对其他疾病有效的药物疾病。抗体药物偶联物（ADC）是一类新兴药物，具有显着的靶点特异性、持久性治疗功效和药物开发的高可转化性。尽管 ADC 前景广阔，但其临床益处脑部疾病，特别是 GBM 的治疗尚未得到证实。不幸的是，最近的中期分析在一项使用抗 EGFRvIII ADC Depatux-M（以前称为 ABT-414）的 3 期研究中显示无存活率接受该 ADC 的新诊断 GBM 患者受益。因此，BBB 穿透性的改善迫切需要 ADC 来推动这种有前途的分子形式走向真正有效和安全的系统性治疗中枢神经系统疾病。我们开发了新颖的 ADC 连接器技术，包括：1) 用于位点特异性和将两个不同的分子同时安装到单个抗体和 2) 可酶切的接头上具有卓越的循环稳定性。利用这些技术，我们成功地构建了均质缀合物附加肽，有助于通过受体介导穿过 BBB 转胞吞作用。与传统的异质肽缀合物相比，其中一种同质肽缀合物变异体，在健康小鼠的脑实质中显示出更多的积累（2.7倍）和原位GBM 异种移植小鼠模型中的肿瘤（3.6倍）。基于这些发现，我们假设同质正确设计的 BBB 穿透肽与 ADC 的结合将是一种有前途的方法全身药物输送至大脑。在这个项目中，我们将制备多种BBB穿透肽和构建具有各种缀合方式的抗体缀合物（接头附着位点、接头结构和肽和有效负载的化学计量）。所有缀合物都将在体外和体内进行血浆评估稳定性、受体介导的转胞吞效率、药代动力学、生物分布、耐受性和免疫原性概况。然后，我们将评估一组 BBB 渗透性 ADC 的肿瘤靶向效率以及基于细胞系和患者来源的原位异种移植小鼠模型的治疗效果 GBM。我们还将进行活体荧光显微镜来评估动力学和动力学健康和荷瘤小鼠模型中的外渗。该项目的成功完成将阐明肽结构和缀合方式的影响抗体偶联物的血脑屏障渗透性以及其他药物特性。我们还期望找出理性的分子设计，释放单克隆抗体和 ADC 对大脑的全部治疗潜力靶向，这可能最终导致新的药物开发策略，以治愈难以治疗的疾病中枢神经系统疾病，例如 GBM。