Microbicide properties of RT inhibitor combinations

RT 抑制剂组合的杀菌特性

基本信息

批准号：
8135250
负责人：
MICHAEL A PARNIAK
金额：
$ 45.02万
依托单位：
UNIVERSITY OF PITTSBURGH AT PITTSBURGH
依托单位国家：
美国
项目类别：
财政年份：
2008
资助国家：
美国
起止时间：
2008-09-10 至 2013-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8135250
关键词：
Antiviral Agents Back CD4 Positive T Lymphocytes Cells Cervical Clinical Trials Clinical assessments Deoxyadenosines Development Disease Drug Formulations Drug resistance Drug-sensitive Economics Educational process of instructing Enzymes Equilibrium Evaluation Film Gel Gender Generations HIV HIV Infections HIV drug resistance HIV vaccine HIV-1 Half-Life Heterosexuals In Vitro Inequality Infection Kinetics Lead Local Microbicides Mediating Memory Metabolism Nucleosides Nucleotides Pharmaceutical Preparations Phase Poliomyelitis Property Risk Sexual Transmission Smallpox System Systemic Therapy Tenofovir Tissue Model UC 781 Vaccines Vagina Variant Virion Virus Woman analog anti-HIV microbicide base chemical property cost effective design inhibitor/antagonist innovation macrophage microbicide non-nucleoside reverse transcriptase inhibitors novel preclinical efficacy preclinical safety prevent research clinical testing resistant strain success topical antiviral transmission process tripolyphosphate uptake

项目摘要

DESCRIPTION (provided by applicant): Topical microbicides are an important strategy to minimize heterosexual transmission of HIV. Several single agent microbicides are in clinical trials, including one based on the nonnucleoside reverse transcriptase inhibitor (NNRTI) UC781 that we discovered as a potential microbicidal agent. However, combination microbicides may be preferable, yet only a single combination microbicide is currently under evaluation. There is also an urgent need to identify new pipeline microbicidal agents. We have found that the nucleoside RT inhibitor (NRTI) 4'-ethynyl-2-fluoro-deoxyadenosine (4'E-2FdA) provides a potent and prolonged barrier to HIV- 1 infection of cells in the subsequent absence of exogenous drug, a property previously only noted for NNRTI such as UC781. The "memory effect" barrier is imparted by 4'E-2FdA at drug levels orders of magnitude less than those needed for protection by the nucleotide tenofovir, currently in clinical assessment for microbicide use. We hypothesize that microbicides comprising combinations of different classes of highly potent RT inhibitors, namely the NNRTI UC781 and an NRTI such as 4'E-2FdA, will provide an optimal barrier to HIV-1 transmission. We therefore propose these Specific Aims for this R21/R33 phased innovation application: R21 Aim 1. To evaluate the in vitro (cell-based) microbicidal properties of NRTI and UC781 alone and in combination. These studies include assessment of antiviral activity and "memory effect" protection imparted by NRTIs and UC781 alone and in combination using primary cells (PBMCs, CD4+ T-cells, macrophages) and different HIV drug-sensitive and drug-resistant strains, isolates and clades. R21 Aim 2. To elucidate the mechanism of 4'E-2FdA (and analogs) induced protective barrier or "memory effect" in HIV susceptible cells. These studies include characterization of uptake, conversion to triphosphate and intracellular stability of the NRTI-TPs, as well as detailed kinetic evaluations of the NRTI substrate activity with enzymes involved in metabolism of the NRTIs. R21 Deliverables: Identification of a lead NRTI and two back-ups for use with UC781 for development as a combination microbicide. R33 Aim 1. To formulate the NRTI/NNRTI combinations selected in the R21 phase into an appropriate delivery system for vaginal topical use. NRTIs and NNRTIs have different chemical properties, thus appropriate delivery systems must be identified to enable incorporation and release of the active agents. We will prepare and evaluate both gel and rapidly dissolving film formulations for the combination microbicide. R33 Aim 2. To evaluate the anti-HIV microbicidal activity of formulated NRTI/NNRTI combinations in an ex vivo cervical explant tissue model. These studies will use a newly developed physiologically relevant polarized cervical tissue model to assess the impact of formulated microbicides alone and in combination on HIV transmission and infectivity. R33 Deliverables: Identification of an appropriate delivery formulation for the selected NRTI/NNRTI combination for entry into subsequent preclinical safety and efficacy studies.

描述（由申请人提供）：局部杀菌剂是减少 HIV 异性传播的重要策略。几种单剂杀菌剂正在进行临床试验，其中包括一种基于非核苷逆转录酶抑制剂 (NNRTI) UC781 的单剂杀菌剂，我们发现它是一种潜在的杀菌剂。然而，组合杀微生物剂可能是优选的，但目前仅评估单一组合杀微生物剂。还迫切需要确定新的管道杀菌剂。我们发现，核苷 RT 抑制剂 (NRTI) 4'-乙炔基-2-氟-脱氧腺苷 (4'E-2FdA) 在随后缺乏外源性药物的情况下，为细胞的 HIV-1 感染提供了有效且持久的屏障，以前仅针对 NNRTI（例如 UC781）注明了该特性。 “记忆效应”屏障是由 4'E-2FdA 产生的，其药物水平比核苷酸替诺福韦保护所需的水平低几个数量级，目前正在对杀微生物剂的使用进行临床评估。我们假设包含不同类别高效 RT 抑制剂（即 NNRTI UC781 和 NRTI 如 4'E-2FdA）组合的杀微生物剂将为 HIV-1 传播提供最佳屏障。因此，我们为 R21/R33 阶段性创新应用提出以下具体目标： R21 目标 1. 评估 NRTI 和 UC781 单独和组合的体外（基于细胞）杀菌特性。这些研究包括评估 NRTI 和 UC781 单独使用以及联合使用原代细胞（PBMC、CD4+ T 细胞、巨噬细胞）以及不同的 HIV 药物敏感和耐药菌株、分离株和进化枝所提供的抗病毒活性和“记忆效应”保护。 R21 目标 2. 阐明 4'E-2FdA（及其类似物）在 HIV 易感细胞中诱导保护屏障或“记忆效应”的机制。这些研究包括 NRTI-TP 的摄取、三磷酸盐转化和细胞内稳定性的表征，以及 NRTI 底物活性与参与 NRTI 代谢的酶的详细动力学评估。 R21 可交付成果：鉴定出一种主要 NRTI 和两种备用药物，可与 UC781 一起开发为组合杀菌剂。 R33 目标 1. 将 R21 阶段选择的 NRTI/NNRTI 组合配制成适合阴道局部使用的递送系统。 NRTI 和 NNRTI 具有不同的化学性质，因此必须确定适当的递送系统以实现活性剂的掺入和释放。我们将制备并评估组合杀菌剂的凝胶和快速溶解薄膜制剂。 R33 目标 2. 在离体宫颈外植体组织模型中评估配制的 NRTI/NNRTI 组合的抗 HIV 杀菌活性。这些研究将使用新开发的生理相关极化宫颈组织模型来评估单独配制的杀菌剂和组合使用的杀菌剂对艾滋病毒传播和感染性的影响。 R33 可交付成果：为选定的 NRTI/NNRTI 组合确定适当的交付配方，以进入后续的临床前安全性和有效性研究。