Chemical Stabilization of shRNAs and their development as hepatitis C drugs

shRNA 的化学稳定性及其作为丙型肝炎药物的开发

基本信息

批准号：
8435514
负责人：
Brian H. Johnston
金额：
$ 78.36万
依托单位：
SOMAGENICS, INC.
依托单位国家：
美国
项目类别：
财政年份：
2007
资助国家：
美国
起止时间：
2007-05-15 至 2015-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8435514
关键词：
Address Adverse effects Animal Model Animals Biodistribution Blood Cells Chemicals Clinical Clinical Trials Collaborations Combined Modality Therapy Development Dose Drug Formulations Elements Firefly Luciferases Funding Genes Genome Goals Hand Health Hepatitis C Hepatitis C virus Human Image Immune system Indiana Infection Inhibitory Concentration 50 Internal Ribosome Entry Site Lead Length Letters Liver Liver diseases Luciferases Mediating Methods Modeling Modification Monkeys Mus Mutation Pan Genus Paper Pathway interactions Pattern Pharmaceutical Preparations Phase Phase I Clinical Trials Positioning Attribute Preparation Prevention Property Publishing RNA RNA Interference Rattus Replicon Reporter Research Resistance Serum Site Staging System Testing Time Toxic effect Toxicology Treatment Efficacy Universities Vaccines Variant Viral Virus Work anti-hepatitis C base design dosage efficacy testing inhibitor/antagonist mouse model mutant nanoparticle novel strategies novel therapeutic intervention phase 1 study pre-clinical preclinical study programs public health relevance research study screening small hairpin RNA success viral RNA

项目摘要

DESCRIPTION (provided by applicant): Hepatitis C virus (HCV) is a worldwide health problem, and its treatment and prevention remain a major challenge. Existing therapies are only partially effective and have serious side effects. No vaccine is currently available. RNA interference (RNAi) offers a novel therapeutic approach for treating HCV infections. We have identified a class of shRNAs, called sshRNAs, which have smaller length and appear to act via a somewhat different pathway than ordinary shRNAs or siRNAs. We have further identified very potent sshRNA (IC50 < 10 pM) targeting the HCV internal ribosome entry site (IRES), a highly conserved and essential but "undruggable" part of the viral RNA. In Phase I, we tested a large number of chemically modified versions of these inhibitors to find types and patterns of modification that would stabilize them in serum without compromising their activity. We identified rules for effective modification and found that such modifications eliminate any stimulation of the innate immune system that can occur with unmodified sshRNAs, particularly if they are blunt-ended. These studies were recently published in two papers in RNA. In Phase II, we will: 1) synthesize chemically modified versions of our alternative lead shRNA using the rules identified in Phase I, and verify their potency and lack of immunostimulatory properties; 2) find optimal combinations of lead shRNAs to minimize shRNA-mediated HCV viral resistant variants; 3) complete screening of nanoparticle formulations to identify the platform that provides the best sshRNA delivery to liver using a mouse reporter model; 4) investigate the toxicity of lead formulated shRNA; and 5) verify the therapeutic efficacy of lead formulated shRNA in an animal model that supports HCV infection. Upon completion of this work, we will be in a very strong position to attract a partner to fund the remaining IND-enabling preclinical studies, file an IND, and proceed with clinical trials.

描述（由申请人提供）：丙型肝炎病毒（HCV）是一个世界性的健康问题，其治疗和预防仍然是一个重大挑战。现有的疗法仅部分有效并且具有严重的副作用。目前尚无疫苗可用。 RNA 干扰 (RNAi) 为治疗 HCV 感染提供了一种新的治疗方法。我们已经鉴定出一类 shRNA，称为 sshRNA，其长度较小，并且似乎通过与普通 shRNA 或 siRNA 略有不同的途径发挥作用。我们进一步鉴定了针对 HCV 内部核糖体进入位点 (IRES) 的非常有效的 sshRNA (IC50 < 10 pM)，IRES 是病毒 RNA 的一个高度保守且必需但“不可成药”的部分。在第一阶段，我们测试了这些抑制剂的大量化学修饰版本，以找到可以在血清中稳定它们而不损害其活性的修饰类型和模式。我们确定了有效修饰的规则，并发现此类修饰消除了未修饰的 sshRNA 可能发生的对先天免疫系统的任何刺激，特别是如果它们是平端的。这些研究最近发表在《RNA》杂志上的两篇论文中。在第二阶段，我们将：1）使用第一阶段确定的规则合成我们的替代先导 shRNA 的化学修饰版本，并验证其效力和缺乏免疫刺激特性； 2) 找到先导 shRNA 的最佳组合，以尽量减少 shRNA 介导的 HCV 病毒耐药变异； 3) 完整筛选纳米颗粒配方，以确定使用小鼠报告模型向肝脏提供最佳 sshRNA 递送的平台； 4) 研究铅配制的shRNA的毒性； 5) 在支持 HCV 感染的动物模型中验证先导配制的 shRNA 的治疗效果。这项工作完成后，我们将处于非常有利的地位，可以吸引合作伙伴资助剩余的 IND 临床前研究、提交 IND 并继续进行临床试验。