Development of Host- Oriented Therapeutics Targeting Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2),

这一阶段应用的最终目标是发现和开发面向宿主的小分子化合物 针对严重急性呼吸系统综合症冠状病毒2(SARS-CoV-2)感染。SARS-CoV-2是一种新的 导致目前人类严重呼吸综合征全球大流行的冠状病毒。抗病毒治疗药物 迫切需要应对SARS-CoV-2和不断涌现的新变种的感染。我们 已经发现了几个针对特定宿主蛋白之间的模块化相互作用的化学系列 含有WW结构域(如Nedd4)和含有PPxY基序的病毒蛋白(如埃博拉VP40)。值得注意的是， 新出现的RNA病毒病原体，如埃博拉、马尔堡、拉萨和狂犬病病毒，都编码PPxY基序， 招募宿主包含WW结构域的蛋白质，以促进病毒有效地扩散、传播和传播。 有趣的是，SARS-CoV-2表面暴露的S蛋白(S)也有一个推测的WW结构域 SARS-CoV-1或更多减毒冠状病毒S蛋白中不存在的结合基序(25PPAY28) 菌株。SARS-CoV-2病毒粒子主要表面蛋白中这个PPAY基序的获得提高了 耐人寻味的可能性是，它可能有助于SARS-CoV-2的独特致病性和/或通过 与特定宿主WW结构域承载蛋白的相互作用。在我们对丝状病毒和丝状病毒的持续研究中 ArenaVirus，我们已经使用广泛的SAR来鉴定一系列能够阻断出口和 活的EBOV、MARV和LAFV在细胞培养中的传播，以及在活的体内阻止疾病的进展 MARV挑战赛模型。在这里，我们假设对我们现有的PPxY/WW-域的“知情的”SAR分析 抑制剂(例如，主要候选FC-10696)将导致发现能够阻断出口和 SARS-CoV-2的疾病进展，以及未来可能出现的相关含PPxY的变种。 为了支持我们的假设，我们提供了强有力的初步数据，表明S蛋白中的PPxY基序 SARS-CoV-2病毒的一部分可以与宿主的WW结构域相互作用，这些蛋白含有促进出口的已知蛋白质 以及EBOV、MARV和LAFV的传播。此外，我们目前领先的候选PPxY发芽抑制剂显示 阻断SARS-CoV-2病毒活体感染人肺上皮细胞出口的活性。在此阶段I 建议，我们将确定和评估以宿主为导向的抑制剂作为治疗SARS-CoV-2和 相关冠状病毒通过结合科学家在药物和药物化学方面的专业知识 福克斯·蔡斯化学多样性中心(FCCDC)拥有哈蒂实验室的专业知识和经验，网址为 宾夕法尼亚大学在病毒-宿主相互作用和抗病毒治疗的实验方面，以及 德克萨斯生物医学研究所Olena Shtanko的实验室评估化合物抗活病毒 在BSL-3条件下。这三个目标是(1)寻找和优化药物化学，包括 ADME图谱，(2)特异性抑制SARS-CoV-2 VLP和PPxY- S介导的宿主蛋白相互作用，以及(3)体外和体内抗SARS-CoV-2病毒的分析。

The ultimate goal of this Phase I application is to discover and develop host-oriented small molecule compounds targeting Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection. SARS-CoV-2 is a novel coronavirus driving the current global pandemic of severe respiratory syndrome in humans. Antiviral therapeutics are urgently needed to combat infection by SARS-CoV-2 and new variants that are continuing to emerge. We have discovered several chemical series that target modular interactions between specific host proteins containing WW-domains (e.g. Nedd4) and viral proteins containing PPxY motifs (e.g. Ebola VP40). Notably, emerging RNA virus pathogens such as Ebola, Marburg, Lassa, and rabies viruses all encode PPxY motifs that recruit host WW-domain containing proteins to facilitate efficient virus egress, spread, and transmission. Interestingly, the surface-exposed Spike glycoprotein (S) of SARS-CoV-2 also has a putative WW-domain binding motif (25PPAY28), that is not present in the S protein of SARS-CoV-1 or more attenuated coronavirus strains. The acquisition of this PPAY motif in the major surface protein of SARS-CoV-2 virions raises the intriguing possibility that it may contribute to the unique pathogenicity and/or transmission of SARS-CoV-2 via interactions with specific host WW-domain bearing proteins. In our ongoing studies on filoviruses and arenaviruses, we have used extensive SAR to identify a lead compound series capable of blocking egress and spread of live EBOV, MARV, and LAFV in cell culture, as well as blocking disease progression in vivo in a live MARV challenge model. Here, we hypothesize that “informed” SAR analyses of our in-hand PPxY/WW-domain inhibitors (e.g. lead candidate FC-10696) will lead to the discovery of analogs capable of blocking egress and disease progression of SARS-CoV-2, as well as related PPxY-containing variants that may emerge in the future. In support of our hypothesis, we present strong preliminary data showing that the PPxY motif within the S protein of SARS-CoV-2 virus can interact with host WW-domain containing proteins that are known to promote egress and spread of EBOV, MARV, and LAFV. Moreover, our current lead candidate PPxY budding inhibitors show activity in blocking egress of live SARS-CoV-2 virus infection in human lung epithelial cells. In this Phase I proposal, we will identify and evaluate host-oriented inhibitors as potential therapeutics for SARS-CoV-2 and related coronaviruses 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 of the Harty Lab at the University of Pennsylvania in the experimental aspects of virus-host interactions and antiviral therapy, and the lab of Olena Shtanko at Texas Biomedical Research Institute for evaluating compounds against live viruses under BSL-3 conditions. The three aims are (1) lead finding and optimization medicinal chemistry including ADME profiling, (2) evaluation for the ability to specifically inhibit egress of SARS-CoV-2 VLPs and PPxY- mediated S-host protein interactions, and (3) in vitro and in vivo analyses against authentic SARS-CoV-2 virus.