Small molecule inhibitory leads against influenza RdRp

描述（由申请人提供）：该项目的总体目标是开发一种安全有效的新型流感病毒感染治疗剂，通过阻断流感聚合酶起作用，流感聚合酶是一种独特的流感蛋白，对病毒复制和感染至关重要。该项目建立在发现新的活性分子的基础上，这些分子是通过使用创新的流感聚合酶测定方法筛选目标文库而发现的。最初发现的活性分子被进一步开发成新的类似药物的分子，在抑制流感聚合酶方面的效力大约是原来的100倍。研究计划建议通过额外的文库合成周期和定向药物化学进一步将这些化合物开发成优化的药物先导物。然后，这些先导化合物可以转移给葛兰素史克公司（GSK），后者是“生物防御伙伴关系”的产品开发合作伙伴。葛兰素史克将负责这种新型一流流感药物的开发、临床试验和分销。与这项工作相关的一些主要创新是；1)我们最初观察到HIV整合酶（临床验证的靶点）的双金属结合位点与流感内切酶之间的机制相似性，这导致了我们的新假设，即这两个机制相似的位点的药效团应该具有有用的共同特征，可用于靶向文库设计。2)新的特定设计和高通量化学的相关开发，允许合成5,992个针对双金属结合位点药效团的新化合物库。3)我们扩展了内部开发的IRdRp迷你基因组（复制子）测定，允许靶向筛选100万种化合物。4)设计和开发一种全新的体外荧光极化（FP）结合实验，以已知的荧光标记内切酶抑制剂和重组PAn内切酶亚基为关键试剂。5)我们发现的新型药物样化合物在IRdRp复制子实验中表现出良好的基于细胞的抑制作用，并在FP内切酶实验中表现出良好的结合。6)我们在上述FP测定中的结合与已发表的一组已知的天然流感内切酶抑制剂的酶抑制相关。7)开发了一种新的重组PAn结构，首次获得了PAn抑制剂的共晶结构。该项目的具体目标是：目标1。新型核酸内切酶、聚合酶和双重抑制剂的先导物优化，使用迭代文库合成和定向药物化学选择两个或多个优化先导物进行开发。目标2。体外和体内铅化合物的保护和治疗效果评价。目标3。通过非glp毒性和药代动力学研究，对符合既定标准的最有希望的口服活性优化先导候选物进行先导优化。

DESCRIPTION (provided by applicant): The overall goal of this project is to develop a safe and effective new therapeutic agent for influenza virus infections that works by blocking influenza polymerase, which is a unique influenza protein that is critical for virus replication an infection. This project builds on the discovery of new active molecules found by the screening of targeted libraries with innovative influenza polymerase assays. The active molecules that were initially discovered were further developed into new drug-like molecules that are about 100 times more potent in the inhibition of influenza polymerase. The research plan proposes to further develop these compounds into optimized drug leads through additional cycles of library synthesis and directed medicinal chemistry. These lead compounds can then be transferred to GlaxoSmithKline (GSK), who is the product development partner as part of a "Partnership for Biodefense". GSK will be responsible for development, clinical trials and distribution of the new first-in-class influenza drug. Some of the major innovations that are associated with this work are; 1) Our original observation regarding the mechanistic similarity between the two-metal binding site of HIV integrase (which is a clinically validated target) and influenza endonuclease, this led to our novel hypothesis that the pharmacophore of these two mechanistically similar sites should share useful common features for targeted library design. 2) The novel specific design and associated development of the high throughput chemistry that allowed for the synthesis of a library of 5,992 new compounds that target the two-metal binding site pharmacophore. 3) Our extension of the internally developed IRdRp mini-genome (replicon) assay that allows for the targeted screening of >10,000 compounds. 4) The design and development of a completely novel in vitro fluorescent polarization (FP) binding assay using a fluorescently labeled known inhibitor of endonuclease and a recombinant PAn endonuclease subunit as the key reagents. 5) Our discovery of novel drug-like compounds that show good cell-based inhibition in the IRdRp replicon assay and also binding in the FP endonuclease assay. 6) Our demonstration that binding in the above FP assay correlates with the published enzyme inhibition for a set of known inhibitors of native influenza endonuclease. 7) The development of a new recombinant PAn construct that has given the first co-crystal structure of an inhibitor with PAn. The Specific Aims of this project are: Aim 1. Lead optimization of novel endonuclease, polymerase and dual inhibitors, using iterative library synthesis and directed medicinal chemistry to select two or more optimized leads for development. Aim 2. Evaluation of the protective and therapeutic efficacy of lead compounds in vitro and in vivo. Aim 3. Conduct lead optimization through non-GLP toxicity and pharmacokinetic studies for the most promising orally-active optimized lead candidates that meet the established criteria. PUBLIC HEALTH RELEVANCE: The overall goal of this project is to develop a safe and effective new therapeutic agent for influenza virus infections that works by blocking influenza polymerase, which is a unique influenza protein that is critical for virus replication and infectio. This project builds on the discovery of new active molecules found by the screening of targeted libraries with innovative influenza polymerase assays. The targeted libraries were designed using insights into the molecular mechanism of this viral polymerase and another viral enzyme called HIV integrase.