HEPATITIS C VIRUS NS5B POLYMERASE INHIBITORS

慢性丙型肝炎是一个尚未解决的重大公共卫生问题，在美国每年困扰400万人，导致1万人死亡。尽管超过50%的患者最终死于肝功能衰竭和/或肝细胞癌，但这通常需要20-30年的时间才能发展起来。这为治疗和预防这种慢性感染的长期后遗症提供了一个很大的窗口。不幸的是，目前对慢性丙型肝炎的治疗仍然相对无效，而且经常有副作用。丙型肝炎病毒NS5B聚合酶(RDRP)一直是丙型肝炎新疗法开发中研究不足的靶点。这项工作的主要目标是进一步鉴定一个新的基于细胞的丙型肝炎病毒NS5B聚合酶系统，并利用它来鉴定可能导致新的丙型肝炎治疗药物的NS5B聚合酶小分子抑制剂。假设：这一新的基于哺乳动物细胞的系统将提供识别和研究选择性抑制丙型肝炎病毒NS5B聚合酶的小分子的手段，并可以为慢性丙型肝炎提供新的治疗选择。进一步发展以哺乳动物细胞为基础的测试，使其有能力在哺乳动物细胞中识别更广泛类别的NS5B聚合酶抑制剂。通过哺乳动物DNA和RNA聚合酶的体外检测以及哺乳动物细胞毒性检测来确定NS5B聚合酶抑制剂的特异性和毒性。提议的商业应用慢性丙型肝炎的有效疗法的市场是巨大的。美国约有400万人患有慢性丙型肝炎，全球慢性丙型肝炎的发病率估计为1.5-2.5%。哺乳动物细胞NS5B-模板/报告系统的专利已经由埃默里大学医学院申请，并授权给三角制药公司。

Chronic hepatitis C is a major unsolved public health problem that afflicts 4 million people and results in 10,000 deaths per year in the USA. Although more than 50 percent of patients eventually succumb to liver failure and/or hepatocellular carcinoma, this frequently takes 20-30 years to develop. This provides a large window for the treatment and prevention of the long-term sequelae of this chronic infection. Unfortunately, current treatments for chronic HCV remain relatively ineffective and frequently have side effects. The hepatitis C virus NS5B polymerase (or RDRP) has been an understudied target for the development of new hepatitis C therapeutics. The primary goal of this work is to further characterize a novel cell-based HCV NS5B polymerase system and use it to identify small molecule inhibitors of NS5B polymerase that may lead to new hepatitis C therapeutics. Hypothesis: This novel mammalian cell-based system will provide the means for identifying and studying small molecules that selectively inhibit the HCV NS5B polymerase and can provide new treatment options for chronic hepatitis C. Specific Objectives: To identify small molecules that inhibit NS5B polymerase, particularly those requiring metabolic activation, using a mammalian cell-based system. To further develop the mammalian cell-based assay so that it has the ability to identify an even broader category of NS5B polymerase inhibitors within mammalian cells. Determine the specificity and toxicity of inhibitors of NS5B polymerase using in vitro assays of mammalian DNA and RNA polymerases, and mammalian cell toxicity assays. PROPOSED COMMERCIAL APPLICATION The market for an effective therapy for chronic hepatitis C is enormous. Approximately 4 million people in the USA have chronic hepatitis C and the world-wide incidence of chronic HCV is estimated at 1.5-2.5 percent. A patent on the mammalian cell NS5B-template/reporter system has been filed by Emory University School of Medicine and licensed to Triangle Pharmaceuticals.