DEVELOPMENT OF SMALL MOLECULE THERAPEUTICS AGAINST RNA VIRUSES

 描述（由申请方提供）：本项目的最终目标是生产一种用于治疗丝状病毒（埃博拉和马尔堡）、沙粒病毒（拉沙热）和弹状病毒（狂犬病）引起的病毒感染的广谱药物。我们和其他人已经确定，这些新出现的人类病原体的有效出芽依赖于宿主蛋白质（如Nedd 4）的破坏，并且这些RNA病毒的基质蛋白表达的PPxY晚期（L）出芽结构域对于这种相互作用至关重要。由于破坏病毒出芽可以防止病毒传播，我们将评估小分子抑制剂破坏宿主Nedd 4-病毒PPxY相互作用的能力，从而防止病毒出芽。我们的合作者，博士迈克尔李和马克奥尔森（USAMRIID，英尺。Detrick，MD）使用含有Nedd 4-PPxY相互作用的已知蛋白质结构进行计算机筛选以发现潜在的竞争性阻断剂。这一努力导致了最初的活性小分子命中，随后通过额外的SAR模拟测试进行了改进。该I期STTR资助申请的目标是通过设计和制备额外的类似物来扩展这一新发现，以了解SAR和初始ADME特性，以支持未来的II期药物发现计划。我们将通过结合福克斯大通化学多样性中心的制药和药物化学专业知识来实现这一目标。（www.fc-cdci.com，FCCDC）与宾夕法尼亚大学Harty实验室在抗病毒治疗的临床和实验方面的专业知识和经验。在本SAR开发提案中，我们将设计和制备适用于物质组成知识产权保护的新型类似物，以了解SAR并提高我们试验中的效价（目标1）。我们将使用BiMC和VLP出芽测定来测试类似物在特异性抑制PPxY-Nedd 4相互作用和随后丝状病毒颗粒流出方面的功效（目的2）。为此，我们还将测试类似物阻断PPxY介导的活病毒出芽的能力，所述活病毒包括VSV、狂犬病、埃博拉（基奎特）、马尔堡（Ci 67）和拉沙热。我们将通过获得高级先导化合物的体外吸收、分布、代谢和分布（ADME）数据和小鼠（IV给药）药代动力学（PK）参数来了解潜在的药物性质问题（目标3）。由于含有基质蛋白的L结构域是许多RNA病毒（包括丝状病毒、沙粒病毒、弹状病毒、副粘病毒和亨尼帕病毒）的有效病毒-细胞分离所需的，我们预测靶向该病毒-宿主相互作用结构域将作为开发新的和强大的广谱抗病毒药物的基础。一旦我们实现了该提案的目标，我们将处于理想的位置，以过渡到一个完整的药物发现和开发计划，作为更广泛的STTR II期的一部分，我们将寻求找到一种或多种PPxY抑制剂，以在详细的IND指导的药代动力学，药效学和毒性研究中进行评估。

 DESCRIPTION (provided by applicant): The ultimate goal of this project is to produce a broad-spectrum drug for the treatment of viral infections caused by filoviruses (Ebola and Marburg), arenaviruses (Lassa fever), and rhabdoviruses (rabies). We and others have determined that efficient budding of these emerging human pathogens is dependent on the subversion of host proteins, such as Nedd4, and that PPxY late (L) budding domains expressed by the matrix proteins of these RNA viruses are critical for such interactions. As disruption of virus budding would prevent virus dissemination, we will evaluate the ability of small molecule inhibitors to disrupt host Nedd4-viral PPxY interactions, thereby preventing virus budding. Our collaborators, Drs. Michael Lee and Mark Olson (USAMRIID, Ft. Detrick, MD), have used a known protein structure containing a Nedd4-PPxY interaction to perform an in silico screen to find potential competitive blockers. This effort led to an initial active small molecule hit that ws subsequently improved with additional SAR analog testing. The goal of this Phase I STTR grant application is to expand this novel finding by designing and preparing additional analogs to understand SAR and initial ADME properties to support a future drug discovery program in Phase II. We will accomplish this by combining the pharmaceutical and medicinal chemistry expertise of the Fox Chase Chemical Diversity Center, Inc. (www.fc-cdci.com, FCCDC) with the expertise and experience of the Harty Lab at the University of Pennsylvania in the clinical and experimental aspects of antiviral therapy. In this SAR development proposal, we will design and prepare novel analogs suitable for composition of matter intellectual property protection to understand SAR and increase potency in our assays (Aim 1). We will use BiMC and VLP budding assays to test analogs for their efficacy at specifically inhibiting the PPxY-Nedd4 interaction and subsequent egress of filovirus particles (Aim 2). In this aim we will also test analogs for their ability to block PPxY-mediated budding of live viruses including VSV, rabies, Ebola (Kikwit), Marburg (Ci67), and Lassa fever. We will seek to understand potential drug property issues by obtaining in vitro absorption, distribution, metabolism and distribution (ADME) data and pharmacokinetic (PK) parameters in mice (IV administration) for advanced lead compounds (Aim 3). As L-domain containing matrix proteins are required for efficient virus-cell separation of many RNA viruses, including filoviruses, arenaviruses, rhabdoviruses, paramyxoviruses, and henipaviruses, we predict that targeting this virus-host interaction domain will serve as the basis for the development of new and powerful broad-spectrum antiviral drugs. Once we achieve the aims of this proposal, we will be ideally positioned to transition into a full drug discovery and development program as part of the more extensive STTR Phase II period where we will seek to find one or more PPxY inhibitors to evaluate in detailed IND-directed pharmacokinetic, pharmacodynamic and toxicity studies.