Development of Small Molecule Therapeutics Targeting Hemorrhagic Fever Viruses

摘要：这一第二阶段应用的最终目标是开发新型的小分子、广谱 治疗由丝状病毒、阿雷纳病毒和其他依赖于 PPxY L-感染出口和传播的结构域基序。其中一些病毒，包括埃博拉病毒(EBOV)， 马尔堡(MARV)和拉沙热(LAFV)病毒具有高致病性，被归类为A类生物恐怖 病原体。我们和其他人已经确定，这些新出现的人类病原体的有效萌发取决于 对宿主蛋白的颠覆，如神经前体细胞发育下调表达 蛋白4(Nedd4)，由PPxY L结构域在这些核糖核酸病毒的基质蛋白中表达。身份识别和 干扰这些病毒-宿主相互作用的小分子抑制剂的开发应该能有效地阻止 病毒扩散、疾病发展和传播。在这些努力中，我们发现了几个化学系列 宿主Nedd4/病毒PPxY复合体的小分子抑制剂对病毒出口很重要，导致了一种 类似物在马尔堡病毒挑战的小鼠模型中具有体内活性的概念证明。作为FDA 目前还没有用于治疗这些病毒感染的已批准的治疗药物，我们的 识别可能阻止病毒传播的病毒宿主抑制物将填补一个重大的未得到满足的需求。此外， 这些抑制剂将是广谱的，因此可能对新出现的病毒有效，因为 以及病毒的变种。如下所述，我们将使用严格的多方面方法来识别、开发和 验证在第一阶段中确定为有效的广谱抗病毒药物的PPxY萌芽抑制药。这一阶段的目标 II STTR赠款申请是为了优化我们的VP40 PPxY-Nedd4相互作用的先导抑制剂，以产生完全的- 成熟的开发前药物候选者准备进行IND指导的研究。这将通过以下方式实现 狐狸大通化学多样性研究所科学家的药物和药物化学专业知识 中心，Inc.(FCCDC)在抗病毒治疗的实验方面拥有专业知识和经验 宾夕法尼亚大学哈蒂实验室。我们将通过优化我们现有的一系列抑制剂来实现这一目标， 以体内活性FC-10696为例，用于改善效力和口服药物特性(目标1)，评估新的 基于两个有效系列的化合物，因为它们能够特异性地抑制PPxY-Nedd4相互作用和 随后的VLP和代理病毒出口(目标2)，鉴定具有合适的药物特性的化合物和 使用体外和体内ADMET评价的选择性(目标3)，以及评价化合物的抗病毒作用 体外和体内对抗正宗BSL-4病毒的有效性(目标4)。

Summary: The ultimate goal of this Phase II application is to develop novel small molecule, broad-spectrum therapeutics against viral infections caused by filoviruses, arenaviruses, and other viruses that depend on the PPxY L-domain motif for egress and spread of infection. Some of these viruses, including Ebola (EBOV), Marburg (MARV), and Lassa fever (LAFV) viruses, are highly pathogenic and classified as Category A bioterror pathogens. We and others have determined that efficient budding of these emerging human pathogens depends on the subversion of host proteins, such as neural precursor cell expressed developmentally down-regulated protein 4 (Nedd4), by PPxY L-domains in the matrix proteins of these RNA viruses. The identification and development of small molecule inhibitors that interfere with these virus-host interactions should effectively block virus egress, disease progression, and transmission. In these efforts we have discovered several chemical series of small molecule inhibitors of the host Nedd4/virus PPxY complex important for viral egress which led to one analog possessing proof of concept in vivo activity in a Marburg virus challenged mouse model. As FDA approved therapeutic agents for the treatment of these most of these viral infections are not available, our identification of virus-host inhibitors that may prevent virus spread will fill a significant unmet need. Moreover, these inhibitors will be broad-spectrum, and therefore will likely be effective against newly emerging viruses as well as viral variants. As described below, we will use a rigorous multifaceted approach to identify, develop, and validate PPxY budding inhibitors identified in Phase I as potent, broad-spectrum antivirals. The goal of this Phase II STTR grant application is to optimize our lead inhibitors of VP40 PPxY-Nedd4 interactions to generate full- fledged predevelopment drug candidates ready for IND directed studies. This will be accomplished by combining the pharmaceutical and medicinal chemistry expertise of the scientists at the Fox Chase Chemical Diversity Center, Inc. (FCCDC) with the expertise and experience in the experimental aspects of antiviral therapy of the Harty Lab at the University of Pennsylvania. We will realize this goal by optimizing our existing series of inhibitors, exemplified by in vivo active FC-10696, for improved potency and oral drug properties (Aim 1), evaluating new compounds based on two potent series for their ability to specifically inhibit PPxY-Nedd4 interactions and subsequent VLP and surrogate virus egress (Aim 2), identifying compounds having suitable drug properties and selectivity using in vitro and in vivo ADMET evaluation (Aim 3), and evaluating compounds for their antiviral efficacy against authentic BSL-4 viruses in vitro and in vivo (Aim 4).