Development of Broad Spectrum Direct Acting Antivirals Against Emerging Alphaviruses

摘要 甲病毒（披膜病毒科属）几种医学上重要的病毒，包括基孔肯雅病毒（CHIKV）， 委内瑞拉马脑炎病毒（VEEV）和东部马脑炎病毒（EEEV）。这些是- 新出现的病毒由于其流行性而被归类为生物防御类别B和C优先病原体 风险或潜在的生物恐怖威胁。尽管这些病毒构成了威胁， 用于治疗任何甲病毒感染因此，我们经验丰富的互动团队将利用我们的 在甲病毒生物学、结构生物学、高通量筛选、药物化学、 和药物开发，以产生靶向保守病毒酶的小分子抑制剂， 生产新的、广谱的、直接作用的抗甲病毒药物。这一努力的核心前提是， 基于小分子的跨甲病毒家族多个成员的必需病毒蛋白的抑制剂可以 采用一个平台开发，该平台（a）整合了目标识别和验证（目标1），（B）确认 并优化针对给定靶标的细胞抗病毒活性和SAR（目标2a），（c）建立并改善 体外ADME和体内药代动力学（目的2b），并进展为体内疗效和毒性 动物模型（目标3）。与Discovery Core B的合作将在功能上验证结构上保守的 甲病毒酶中的化合物结合口袋（RNA依赖性RNA聚合酶（RDRP; nsP 4）， 解旋酶（nsP 2）和nsP 2蛋白酶）。这些分析将为命中发现的病毒靶点的选择提供信息 使用物理和计算机筛选的组合与核心B协调。击中那些显示 将与药物化学核心（核心C）合作优化稳健的靶点参与， 抑制、稳定性、选择性、溶解性、渗透性、药代动力学和体外抗病毒活性 多种甲病毒（CHIKV、EEEV和VEEV）。由于我们的目标是确定广泛的活性化合物，铅 还将针对其他甲病毒（例如RRV、MAYV、ONNV、WEEV和SINV）对化合物进行检测 以及我们计划中的其他病毒，包括冠状病毒（Proj. 1和2）、黄病毒（Proj. 4）和丝状病毒 （项目1999年）5）。我们还将与Enzymology Core D合作，以确定其抗病毒作用机制。铅 具有最佳体内生物分布和稳定性的化合物将使用我们的方法测试体内抗病毒功效。 建立的甲病毒诱导的关节炎（CHIKV）或脑炎（VEEV或EEEV）模型。的考生 有效的体内抗病毒功效将进一步优化制剂、毒性和高级PK/PD。

ABSTRACT Alphaviruses (Togaviridae genus) several medically important viruses, including chikungunya virus (CHIKV), Venezuelan equine encephalitis virus (VEEV), and Eastern equine encephalitis virus (EEEV). These re- emerging viruses are categorized as Biodefense Category B and C priority pathogens due to their pandemic risk or potential as bioterror threats. Despite the threat posed by these viruses, there are no approved antivirals for treating any alphavirus infection. Therefore, our highly experienced and interactive team will leverage our world class expertise in alphavirus biology, structural biology, high throughput screening, medicinal chemistry, and drug development to generate small molecule inhibitors targeting conserved viral enzymes with the goal of producing new, broad spectrum, direct acting anti-alphaviral drugs. The central premise of this effort is that small molecule-based inhibitors of essential viral proteins across multiple members of the Alphavirus family can be developed employing a platform that (a) integrates target identification and validation (Aim 1), (b) confirms and optimizes cellular antiviral activity and SAR against the given target (Aim 2a), (c) establishes and improves in vitro ADME and in vivo pharmacokinetics (Aim 2b), and progresses leads into in vivo efficacy and toxicity animal models (Aim 3). Collaboration with the Discovery Core B will functionally validate structurally conserved compound binding pockets in alphaviruses enzymes (RNA dependent RNA polymerase (RDRP; nsP4), the RNA helicase (nsP2), and the nsP2 protease). These analyses will inform the selection of viral targets for hit discovery using a combination of physical and in silico screening in coordination with Core B. Hit compounds that show robust target engagement will be optimized in collaboration with the Medicinal Chemistry Core (Core C) for target inhibition, stability, selectivity, solubility, permeability, pharmacokinetics, and antiviral activity in vitro against multiple alphaviruses (CHIKV, EEEV, and VEEV). As our goal is to identify broadly active compounds, lead compounds will also be tested agAainst additional alphaviruses (e.g. RRV, MAYV, ONNV, WEEV, and SINV) and other viruses in our program, including coronaviruses (Proj. 1 and 2), flaviviruses (Proj. 4), and filoviruses (Proj. 5). We will also collaborate with Enzymology Core D to identify their antiviral mechanism of action. Lead compounds with optimal in vivo biodistribution and stability will be tested for in vivo antiviral efficacy using our established models of alphavirus-induced arthritis (CHIKV) or encephalitis (VEEV or EEEV). Candidates with potent in vivo antiviral efficacy will be further optimized for formulation, toxicity, and advanced PK/PD.