Ultrapotent Inhibitors of Wild-type and Multi-drug Resistant HIV

野生型和多重耐药艾滋病毒的超强抑制剂

• 批准号: 9042221
• 负责人: Stefan G Sarafianos
• 金额: $ 41.32万
• 依托单位: UNIVERSITY OF MISSOURI-COLUMBIA
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-07-01 至 2019-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9042221
• 关键词: 2' -deoxyadenosine; Active Sites; Adherence; Affect; Affinity; Animals; Anti-HIV Agents; Anti-Retroviral Agents; Antiviral Agents; Binding; Biochemical; Chemistry; Chronic; Clinical; Combined Modality Therapy; Complex; DNA; DNA-Directed DNA Polymerase; Deamination; Deoxycytidine Kinase; Development; Drug Combinations; Drug Kinetics; Drug resistance; FDA approved; Funding; Future; Genetic; HIV; HIV Infections; HIV drug resistance; HIV resistance; Highly Active Antiretroviral Therapy; In Vitro; Lead; Macaca; Modality; Multi-Drug Resistance; Mutate; Mutation; Nucleosides; Nucleotides; Patients; Pharmaceutical Preparations; Phosphorylation; Property; Prophylactic treatment; Proteins; Regimen; Reporting; Research; Resistance; Resistance development; Resistance profile; Reverse Transcriptase Inhibitors; SIV; Structure; Tenofovir; Therapeutic; Viral Load result; Virus; Work; adenosine deaminase; base; clinically significant; design; drug resistant virus; indexing; inhibitor/antagonist; insight; novel; novel therapeutics; nucleoside analog; polymerization; prevent; public health relevance; tripolyphosphate; viral DNA

DESCRIPTION: Nucleoside reverse transcriptase inhibitors (NRTIs) are key components of Highly Active Antiretroviral Therapies (HAART) for the treatment of HIV-infected patients. All FDA-approved anti-HIV NRTIs lack a 3'-OH, and therefore inhibit DNA polymerization by HIV RT through immediate chain termination. The absence of a 3'-OH also imparts detrimental properties to these NRTIs by reducing their binding affinity for RT compared to the natural dNTP substrates and reducing intracellular conversion to active NRTI triphosphates. We have reported during the first funding cycle that 4'-ethynyl-2-fluoro-2'-deoxyadenosine (EFdA) is a nucleoside analog that retains the 3'-OH moiety and demonstrates exceptional antiviral properties (EC50 = 50 pM in PBMCs) and a remarkable selectivity index (>200,000). EFdA's potency and selectivity index is by orders of magnitude more favorable than all currently-approved anti-HIV drugs. Despite the presence of a 3'-OH, the incorporated EFdA-monophosphate acts primarily as an immediate chain terminator because RT has difficulty translocating on the primer possessing 3'-terminal EFdA-MP, which is a unique mechanism of action. Therefore, EFdA-TP is a Translocation-Defective RT inhibitor (TDRTI). Additionally, EFdA has also been shown to efficiently inhibit clinically-important NRTI-resistant HIV strains, and demonstrating hypersusceptibility to the tenofovir-resistant K65R HIV. Notably, in our study of SIV-infected macaques the animals that had suppressed viral loads upon treatment with EFdA carried the M184V mutation, suggesting that M184V can be effectively suppressed by EFdA. We have also shown that EFdA has a remarkably high barrier for HIV resistance, and many EFdA-resistant HIV strains have reduced replication capacity. More recently we have shown that the combination of EFdA with Rilpivirine shows a synergistic effect, which would be useful in the design of new therapeutic regimens. We will build on our work from the first funding cycle to understand the potency of EFdA at the RT and cellular levels, development of EFdA resistance, and EFdA combinations with currently-approved anti-HIV drugs. We will also use biochemical and structural approaches to characterize the inhibition mechanism of EFdA at the RT level, the activation of EFdA by deoxycytidine kinase (dCK) and deamination by adenosine deaminase (ADA). This study will provide information that will guide the design of novel NRTIs and EFdA combination therapies with other approved anti-HIV drugs that may lead to a breakthrough in the treatment of HIV infection.

描述：核苷逆转录酶抑制剂 (NRTI) 是治疗 HIV 感染患者的高效抗逆转录病毒疗法 (HAART) 的关键成分。所有 FDA 批准的抗 HIV NRTI 都缺乏 3'-OH，因此通过立即链终止来抑制 HIV RT 引起的 DNA 聚合。与天然 dNTP 底物相比，3'-OH 的缺失也会降低这些 NRTI 对 RT 的结合亲和力，并减少细胞内向活性 NRTI 三磷酸的转化，从而赋予这些 NRTI 有害的特性。 我们在第一个资助周期中报告说，4'-乙炔基-2-氟-2'-脱氧腺苷 (EFdA) 是一种核苷类似物，保留了 3'-OH 部分，并表现出卓越的抗病毒特性（PBMC 中的 EC50 = 50 pM）和显着的选择性指数（>200,000）。 EFdA 的效力和选择性指数比目前批准的所有抗 HIV 药物要好几个数量级。尽管存在 3'-OH，但掺入的 EFdA-单磷酸盐主要充当直接链终止子，因为 RT 难以在具有 3'-末端 EFdA-MP 的引物上易位，这是一种独特的作用机制。因此，EFdA-TP 是一种易位缺陷型 RT 抑制剂 (TDRTI)。此外，EFdA 还被证明可以有效抑制临床上重要的 NRTI 耐药 HIV 菌株，并表现出对替诺福韦耐药 K65R HIV 的高度敏感性。值得注意的是，在我们对感染 SIV 的猕猴的研究中，经 EFdA 治疗后病毒载量受到抑制的动物携带 M184V 突变，表明 EFdA 可以有效抑制 M184V。我们还表明，EFdA 对 HIV 耐药具有非常高的屏障，并且许多 EFdA 耐药 HIV 毒株的复制能力降低。最近我们发现 EFdA 与 Rilpivirine 的组合显示出协同作用，这将有助于设计新的治疗方案。 我们将从第一个资助周期开始，以我们的工作为基础，了解 EFdA 在 RT 和细胞水平上的效力、EFdA 耐药性的发展以及 EFdA 与目前批准的抗 HIV 药物的组合。我们还将使用生化和结构方法来表征 EFdA 在 RT 水平上的抑制机制、脱氧胞苷激酶 (dCK) 激活 EFdA 以及腺苷脱氨酶 (ADA) 脱氨作用。 这项研究将提供信息，指导新型 NRTI 和 EFdA 联合疗法与其他已批准的抗 HIV 药物的联合疗法的设计，这可能会导致 HIV 感染治疗的突破。