Small-molecule inhibitors of gp41-mediated fusion as HIV-1 topical microbicides

gp41 介导融合的小分子抑制剂作为 HIV-1 局部杀菌剂

• 批准号: 8743614
• 负责人: Min Lu
• 金额: $ 44.84万
• 依托单位: RBHS-NEW JERSEY MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-01-06 至 2016-01-05
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8743614
• 关键词: Small; molecule; inhibitors; gp41; mediated

DESCRIPTION (provided by applicant): In the continuing absence of an effective vaccine, topical microbicides offer a credible alternative preventive strategy to reduce sexual transmission of HIV-1. Several viral fusion and entry inhibitors have been shown to prevent SHIV infection of rhesus macaques by the vaginal and/or rectal routes and are in preclinical and early clinical development as microbicide candidates. HIV-1 membrane fusion is mediated by a series of large-scale structural transitions in the gp41 envelope glycoprotein. Evidence indicates that a transient gp41 species known as the prehairpin intermediate is a potential target for drugs that inhibit HIV-1 entry. The long-term goal of this research plan is to use modern molecular and structural methods to identify and develop a novel small-molecule gp41 fusion inhibitor for inclusion in a topical HIV-1 microbicide. To achieve this, we will capitalize on specific surface features revealed by our recent structure determination of an autonomously folded, trimeric coiled-coil subdomain of gp41 that provides an atomic model for the putative prehairpin conformation, as well as small-molecule lead compounds developed by means of an innovative structure-based drug design technology. We propose the following specific aim for the R21 component of this project: 1) To identify and optimize two series of novel small-molecule compounds that inhibit HIV-1 membrane fusion by targeting the gp41 prehairpin intermediate. We will design and synthesize two sets of analogs of active triazinone and biphenyl compounds, characterize the equilibrium properties of interactions with the N-trimer coiled coil, and evaluate their anti-HIV-1 activity and mechanism of action. Bound inhibitors will be visualized by x-ray crystallography in order to allow refinement of binding affinity. The specific aims of the R33 phase of the project are: 2) To characterize the specificity, potency and toxicity of improved small-molecule compounds with enhanced gp41 inhibitory activity. We will conduct in vitro studies in primary cells and human cervicovaginal tissue explants to determine the virucidal activity of select small-molecule gp41 inhibitory compounds against diverse primary HIV-1 isolates, and their potentially toxic or inflammatory effects. We will also use the rabbit vaginal irritation model to evaluate the irritation potential of the fusion inhibitors. 3) To assess the in vivo potency and breadth of activity of optimized small-molecule fusion inhibitors alone and in combination with entry inhibitors targeting HIV-1 gp120 (BMS-378806) and CCR5 (CMPD167) using the NOD/SCID-hu BLT mouse vaginal transmission model. We will evaluate the protection of humanized BLT mice from vaginal challenge with multiple HIV-1 variants by small-molecule fusion inhibitors alone and in synergistic combination with BMS-378806 and CMPD167. Our emphasis is to identify a new class of potent HIV-1 fusion inhibitors suitable for development as a component of a microbicide formulation.

描述（由申请人提供）：在继续没有有效的疫苗的情况下，局部菌皮提供了一种可靠的替代预防策略来减少HIV-1的性传播。已经证明了几种病毒融合和进入抑制剂可防止阴道和/或直肠路线对恒河猴的湿颈猕猴感染，并且在临床前和早期临床发育中作为候选者。 HIV-1膜融合是由GP41包膜糖蛋白中的一系列大规模结构过渡介导​​的。证据表明，称为hairpin前中间体的瞬时GP41物种是抑制HIV-1进入的药物的潜在靶标。该研究计划的长期目标是使用现代分子和结构方法来识别和开发一种新型的小分子GP41融合抑制剂，将其纳入局部HIV-1菌心中。为了实现这一目标，我们将利用我们最近对GP41的自主折叠，三聚盘盘线圈子域的结构来揭示的特定表面特征，该结构为推定的预兆蛋白构象提供了原子模型，以及通过基于创新的基于创新的基于基于创新的药物设计技术而开发的小分子铅化合物。我们提出了该项目的R21组件的以下特定目的：1）识别和优化两种新型的小分子化合物，这些化合物通过靶向GP41 Prehairpin中间体来抑制HIV-1膜融合。我们将设计和合成活性三唑酮和双苯基化合物的两组类似物，表征与N-Trimer盘绕线圈相互作用的平衡性能，并评估其抗HIV-1活性和作用机理。结合抑制剂将通过X射线晶体学可视化，以允许结合亲和力的细化。该项目的R33阶段的具体目的是：2）表征具有增强的GP41抑制活性的改进小分子化合物的特异性，效力和毒性。我们将在原代细胞和人宫颈阴道组织外植体进行体外研究，以确定针对多种原代HIV-1分离株的精选小分子GP41抑制性化合物的病毒活性，以及​​其潜在的毒性或炎症作用。我们还将使用兔阴道刺激模型来评估融合抑制剂的刺激潜力。 3）评估优化小分子融合抑制剂的体内效能和活动的广度，并结合针对HIV-1 GP120（BMS-378806）和CCR5（CMPD167）的入口抑制剂（使用NOD/Scid-Hu BLT BLT BLT小鼠阴道传播模型）。我们将通过单独的小分子融合抑制剂以及与BMS-378806和CMPD167的协同组合评估对人性化BLT小鼠免受阴道挑战的保护。我们的重点是确定适合开发的新型有效的HIV-1融合抑制剂，作为菌心配方的组成部分。