Discovery of Bunyaviral Endonuclease Inhibitors for Antiviral Therapy

用于抗病毒治疗的布尼亚病毒核酸内切酶抑制剂的发现

• 批准号: 10683329
• 负责人: Gaya K. Amarasinghe
• 金额: $ 27.21万
• 依托单位: MICROBIOTIX, INC
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-12 至 2024-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10683329
• 关键词: Acids; Address; Affinity; African; Americas; Animals; Antiviral Agents; Antiviral Therapy; Binding; Biochemical; Biological Assay; Bunyaviridae; Case Fatality Rates; Category A pathogen; Cell Culture Techniques; Cell Line; Cells; Chemicals; Classification; Collaborations; Country; Culicidae; Derivation procedure; Development; Disease Outbreaks; Drug Kinetics; Epidemic; Europe; Exhibits; FDA approved; Family; Fluorescence Resonance Energy Transfer; Genus Phlebovirus; Goals; Human; In Vitro; Infection; Influenza; Insect Vectors; Isotope Labeling; Knowledge; Life Cycle Stages; Livestock; Mammalian Cell; Measurement; Measures; Medical; Modeling; Mutation; N-terminal; National Institute of Allergy and Infectious Disease; Orthobunyavirus; Pathogenicity; Patients; Pharmaceutical Preparations; Phase; Property; Proteins; Publishing; RNA Polymerase Inhibitor; RNA Viruses; RNA-Directed RNA Polymerase; Rift Valley fever virus; Risk; Running; Sampling; Series; Serum; Specificity; Structure; Structure-Activity Relationship; System; Therapeutic; Therapeutic Agents; Toxic effect; Vaccines; Validation; Vesicular stomatitis Indiana virus; Viral; Viral Genome; Viral Hemorrhagic Fevers; Viral Physiology; Virus; Virus Diseases; Virus Replication; counterscreen; cytotoxicity; drug discovery; economic impact; endonuclease; epizootic; experience; global health; high throughput screening; human disease; in vivo; influenzavirus; inhibitor; innovation; lead series; meter; mosquito-borne; novel; nucleoside analog; pathogenic virus; prophylactic; small molecule; small molecule inhibitor; small molecule libraries; therapeutic vaccine; viral RNA

Abstract Segmented negative-sense, single-stranded RNA viruses (sNSVs), which include bunyaviruses, are causative agents of human diseases. Rift Valley Fever Virus (RVFV), a bunyavirus, causes hemorrhagic fever in humans with a case fatality rate of patients developing hemorrhagic fever reaching approximately 50% and has been classified by the NIAID as a Category A Priority Pathogen. RVFV is mosquito-borne, but is also capable of using a wide range of insect vectors with potential to spread to Europe and the Americas. RVFV has the potential to cause significant global health and economic impact. Unfortunately, there are no FDA-approved drugs or vaccines for the treatment of the RVFV infection. Therefore, there is an urgent medical need for more potent therapeutics tailored for RVFV. The overall goal of this project is to identify and develop small molecule prophylactics and/or therapeutics for RVFV infections and preferably also for infections of other highly related bunyaviruses. The strategy is to address the unmet medical need by identifying small molecule inhibitors targeting the enzymatic activity of the essential RVFV endonuclease, which exhibits significant structural similarity to other sNSV endonucleases. The approach is to leverage the team’s experience with bunyaviral endonucleases and a homogeneous FRET-based biochemical assay to identify small molecules that inhibit the enzymatic activity of bunyaviral endonucleases. In Preliminary Studies, we developed a FRET-endonuclease activity (FRET-EA) assay for RVFV endonuclease and applied the assay in a low/medium-throughput format with Z’-factors ≥0.9. The FRET assay confirmed the inhibition of an FDA approved antiviral to treat Influenza virus (IAV), Baloxavir acid (BXA), against IAV endonuclease. In Phase I, for Aim 1, the FRET-EA assay will be optimized for high-throughput screening. Biochemical and cellular secondary assays, including FRET, thermal shift, and cell-based infectious assays, will be optimized to further evaluate confirmed hits. In Aim 2, the FRET- EA HTS will be applied to diverse chemical libraries of ≥250,000 small molecules for the identification and confirmation of small molecules that inhibit the enzymatic activity of RVFV endonuclease. In Aim 3, hits identified in Aim 2 will be validated in secondary assays for binding to endonuclease, anti-sNSV spectrum, and potency against infectious RVFV. They will also be prioritized based on their drug-likeness and their ADME properties. In Phase II, we will perform structural based mechanism studies and further chemically optimize priority inhibitors for potency, selectivity, in vitro and in vivo pharmacokinetics properties and evaluate them in animal infection models.

抽象的 分段的负态，单链RNA病毒（SNSV），包括Bunyaviruses，是病因 人类疾病的药物。裂谷发烧病毒（RVFV），一种Bunyavirus，引起人类出血热 患有出血热的患者病例死亡率达到约50％，已经 由NIAID分类为优先病原体。 RVFV是蚊子出生的，但也能够使用 具有传播到欧洲和美洲的潜力的广泛的绝缘载体。 RVFV有可能 引起重大的全球健康和经济影响。不幸的是，没有FDA批准的药物或 治疗RVFV感染的疫苗。因此，紧急医疗需要更有效 为RVFV量身定制的治疗剂。该项目的总体目标是识别和发展小分子 预防性和/或治疗RVFV感染，并且优先用于其他高度相关的感染 Bunyaviruses。该策略是通过识别小分子抑制剂来满足未满足的医疗需求 靶向必需RVFV核酸内切酶的酶活性，该核酸酶表现出明显的结构 与其他SNSV核酸内切酶相似。方法是利用团队在Bunyaviral的经验 核酸内切酶和均质的基于FRET的生化测定法，以鉴定抑制抑制的小分子 Bunyaviral核酸内切酶的酶活性。在初步研究中，我们开发了一个fret-核酸酶 RVFV核酸内切酶的活性（FRET-EA）测定 Z-Factors≥0.9。 FRET分析证实了对FDA批准的抗病毒病毒治疗流感的抑制作用 病毒（IAV），巴洛萨维尔酸（BXA），针对IAV核酸内切酶。在第一阶段，对于AIM 1，FRET-EA测定将是 优化用于高通量筛选。生化和细胞次要测定，包括特里，热剂 将优化转移和基于细胞的传染性测定，以进一步评估确认的命中。在AIM 2中，烦恼 - EA HTS将用于≥250,000个小分子的潜水化学文库，以进行识别和 确认抑制RVFV核酸内切酶的酶活性的小分子。在AIM 3中，命名为命中 在AIM 2中，将在辅助测定中验证，以结合内切核酸酶，抗SNSV光谱和效力 反对感染性RVFV。他们还将根据他们的毒品和ADME特性来优先考虑它们。 在第二阶段，我们将进行基于结构的机制研究，并进一步化学优先级抑制剂 为了效力，选择性，体外和体内药代动力学特性，并在动物感染中进行评估 型号。