Fatty Acid Synthase Inhibitors As Broad Spectrum Anti-Flaviviral Therapeutics

描述(申请人提供)：登革病毒(DENV)是临床上最重要的虫媒病毒，也是A类生物恐怖分子。与其他正链RNA病毒一样，DENV重排细胞膜以建立独特的胞浆结构，这些结构是复制复合体形成的位置。我们发现DENV利用细胞脂肪酸的生物合成来建立其复制位置。病毒的NS3蛋白与脂肪酸合成酶(FASN)结合，将其招募到病毒复制的位置，并刺激其活性。以下项所需的NS3域 已定义FASN绑定。FASN相互作用结构域的突变证实了NS3-FASN相互作用对于复制是绝对必要的。重要的是，FASN抑制剂可以阻止DENV和包括西尼罗河病毒和黄热病病毒在内的其他黄病毒的复制。此外，FASN途径还与许多其他病毒的复制有关，包括艾滋病毒、丙型肝炎病毒、流感和巨细胞病毒。这表明，如果耐受，FASN抑制剂可能是一种广谱抗病毒治疗药物。我们已经确定了一种符合这一标准的FASN抑制剂先导化合物IPI-9119。它在细胞培养和冰的肝脏和肺中抑制FASN。该化合物具有口服生物利用度，并且不可逆地抑制FASN的硫酯酶结构域。体外和小鼠的毒性研究表明，该抑制剂耐受性良好，最低限度 毒性问题。这个项目是三个小组之间的合作。兰德尔实验室已经表征了DENV-FASN的相互作用，并在体外评估了FASN抑制剂的抗病毒活性。戴蒙德实验室在黄病毒研究方面处于领先地位，在DENV和西尼罗河病毒动物模型和抑制剂测试方面经验丰富。Infinity小组开发了FASN抑制剂类别，并在体内鉴定了其有效性和(无)毒性。他们在药物化学、动物毒性测试和支持IND的研究分析方面拥有专业知识。我们建议在体外和小鼠模型中测试该化合物对DENV和WNV感染的有效性，然后向IND提交申请。我们将在体外和体内验证FASN抑制剂对DENV感染的疗效。将在细胞培养和小鼠模型中表征抗DENV的活性，同时评估耐药机制。将进行进一步的药物评估，评估药代动力学、药效学和各种毒性测试，以推动这些化合物进入IND备案。该项目将把一种可能的广谱抗病毒药物转移到IND申请进行临床试验，该药物针对的是登革热病毒复制抑制剂中具有良好特征的病毒-宿主相互作用。重要的是，尽管该抑制剂针对的是一种重要的细胞酶，但它对小鼠是无毒的。

DESCRIPTION (provided by applicant): Dengue virus (DENV) is the most clinically important arbovirus and a Category A bioterrorism agent. As with other positive stranded RNA viruses, DENV rearranges cellular membranes to establish unique cytosolic structures that are the sites of replication complex formation. We found that DENV co-opts cellular fatty acid biosynthesis to establish its sites of replication. The viral NS3 protein binds to fatty acid synthase (FASN), recruits it to sites of viral replication, and stimulates its activity. The NS3 domain required for FASN binding has been defined. Mutation of the FASN interaction domains established that the NS3-FASN interaction is absolutely essential for replication. Importantly, FASN inhibitors block the replication of DENV and other flaviviruses including West Nile virus and yellow fever virus. Additionally the FASN pathway has been implicated in the replication of many other viruses, including HIV, HCV, influenza, and HCMV. This suggests that FASN inhibitors may be a broad spectrum antiviral therapeutic if tolerated. We have identified a FASN inhibitor lead compound, IPI- 9119, that fits this criteria. It inhibits FASN in cell culture and in the liver and lungs of ice. The compound is orally bioavailable and irreversibly inhibits the thioesterase domain of FASN. Toxicity studies in vitro and in mice demonstrate that the inhibitor is well tolerated with minimal toxicity issues. This project is a collaboration between three groups. The Randall lab has characterized the DENV- FASN interaction and has assessed antiviral activity of FASN inhibitors in vitro. The Diamond lab are leaders in flavivirus research and are highly experienced with DENV and West Nile Virus animal models and inhibitor testing. The Infinity group developed the FASN inhibitor class and characterized its efficacy and (lack of) toxicity in vivo. They have expertise in medicinal chemistry, animal toxicity testing, and analysis of IND-enabling studies. We propose to test the efficacy of this compound against DENV and WNV infection in vitro and in mouse models and then build toward an IND filing. We will validate the efficacy of FASN inhibitors against DENV infection in vitro and in vivo. Anti-DENV activity will be characterized in cell culture and mouse models, while mechanisms of resistance are evaluated. Further drug evaluation assessing pharmacokinetics, pharmacodynamics, and various toxicity assays will be performed to advance these compounds toward IND filing. This project will move a likely broad-spectrum antiviral that targets a well-characterized virus-host interaction in dengue virus replication inhibitor into IND filing for clinical trials. Importantly, although the inhibitor targets an important cellular enzyme, it is non-toxic in mice.