Broad-spectrum antiviral GS-5734 to treat MERS-CoV and related emerging CoV

项目摘要 人畜共患病病毒，如丝状病毒和冠状病毒(CoV)，对全球 公共卫生，因为它们不可预测地出现，导致毁灭性的大流行性疾病爆发。在 21世纪严重急性呼吸综合征冠状病毒与中东呼吸 综合征冠状病毒(MERS-CoV)从人畜共患病的病毒池中出现，在 人类。MERS冠状病毒在中东的骆驼中流行，人类不断有新的感染。 尽管SARS-CoV目前不构成威胁，但已从 在人类细胞中高效复制并对现有疗法具有抵抗力的蝙蝠。与变幻莫测的 人类和野生动物生态的重叠，新型冠状病毒出现在人类身上的可能性很高 很有可能。目前，还没有批准的抗病毒疗法来治疗任何人类冠状病毒感染。广谱 控制已知的人和人畜共患冠状病毒感染的冠状病毒疗法将解决立即未满足的 医疗需要，并可能应对未来的大流行。在与Gilead Sciences的合作中，我们有 证明核苷前药GS-5734在抑制多发性人类和多发性硬化方面非常有效。 人畜共患冠状病毒体外和体内SARS冠状病毒。我们计划的主要目标是加速临床前 开发GS-5734并促进MERS-CoV指示的IND许可。要彻底评估 抗病毒活性的广度和对未来新出现的冠状病毒的疗效预测，我们还将评估疗效 针对代表家庭范围遗传多样性的冠状病毒小组，包括流行前的人畜共患病毒株 蓄势待发。专注于高致病性的MERS冠状病毒，我们独特的合作伙伴关系包括：i) 元基因组学与重组病毒合成基因组回收，II)原代人肺细胞模型，III) 尖端病毒学和生物化学，iv)健壮的小鼠和灵长类动物人类疾病模型和v)状态 ART代谢和药代动力学分析。在目标1中，我们提炼了药物动力学、药效学 通过对GS-5734在各种原代人体细胞中的功效和代谢研究，获得了不同的 人和人畜共患冠状病毒阵列及对小鼠和非人的体内疗效评价 MERS和SARS冠状病毒的灵长类动物模型。在目标2中，我们选择对SARS冠状病毒和MERS的抵抗力- CoV，并确定耐药性对病毒复制、适应性和治疗敏感性的影响。在AIM 3，我们确定GS-5734的作用机制是否是直接影响病毒RNA复制的结果 通过深度测序和单分子RNA原位荧光检测抗病毒免疫的变化 载体或药物处理过的感染细胞和小鼠的杂交。我们制定了广泛的发展战略- 光谱疗法可以扩展到威胁全球的多种新兴病毒病原体 公共卫生。

Project Summary Zoonotic viruses, like filoviruses and coronaviruses (CoV), represent a continuous and growing threat to global public health because they unpredictably emerge causing devastating outbreaks of pandemic disease. In the 21st century, severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV) emerged from zoonotic pools of viruses, causing severe disease in humans. MERS-CoV is endemic in camels in the Middle East with continuous new infections in humans. Although SARS-CoV is not currently a threat, several “prepandemic” SARS-like CoVs have been isolated from bats that replicate efficiently in human cells and are resistant to existing therapies. With the unpredictable overlap of human and wild animal ecologies, the potential for novel CoV emergence into humans is highly probable. Currently, there are no approved antiviral therapies for any human CoV infection. Broad-spectrum CoV therapies that control known human and zoonotic CoV infections would address an immediate unmet medical need and could counter future pandemic episodes. In partnership with Gilead Sciences, we have demonstrated that the nucleoside prodrug, GS-5734, is highly efficacious in inhibiting multiple human and zoonotic CoV in vitro and SARS-CoV in vivo. The primary goal of our program is to accelerate the preclinical development of GS-5734 and promote IND licensure for the MERS-CoV indication. To thoroughly evaluate the breadth of antiviral activity and predict efficacy against future emerging CoV, we will also assess efficacy against a panel of CoV representative of family-wide genetic diversity, including prepandemic zoonotic strains poised for emergence. Focusing on the highly pathogenic MERS-CoV, our unique partnership integrates: i) metagenomics and recombinant virus synthetic genome recovery, ii) primary human lung cell models, iii) cutting edge virology and biochemistry, iv) robust murine and primate models of human disease and v) state of the art metabolic and pharmacokinetic analysis. In Aim 1, we refine the pharmacokinetics, pharmacodynamics and breadth of GS-5734 through efficacy and metabolism studies in various primary human cells with a diverse array of human and zoonotic CoV and through the evaluation of in vivo efficacy in murine and non-human primate models of MERS- and SARS-CoV. In Aim 2, we select for resistance against SARS-CoV and MERS- CoV, and determine the effect of resistance on virus replication, fitness and susceptibility to treatment. In Aim 3, we determine if the mechanism of action of GS-5734 is a result of direct effects on viral RNA replication and/or alteration of antiviral immunity via deep sequencing and single molecule RNA fluorescence in situ hybridization of vehicle or drug treated infected cells and mice. We articulate a development strategy for broad- spectrum therapeutics that could be extended to a multitude of emerging viral pathogens threatening global public health.