Investigation of ATV-Based Heterobifunctional Degraders to Combat Growing HIV-1 PR Inhibitor Resistance

研究基于 ATV 的异双功能降解剂以对抗日益增长的 HIV-1 PR 抑制剂耐药性

• 批准号: 10484347
• 负责人: CHRISTINA OCHSENBAUER
• 金额: $ 22.7万
• 依托单位: UNIVERSITY OF ALABAMA IN TUSCALOOSA
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-04 至 2024-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10484347
• 关键词: Affinity; Antiviral Agents; Atazanavir; Autoimmune Diseases; Binding; Binding Proteins; Binding Sites; Biological; Biological Assay; Biological Availability; Biology; Cell membrane; Cells; Clinic; Clinical Trials; Complex; Computing Methodologies; Development; Dimerization; Drug resistance; Epidemic; Event; Exhibits; Failure; Foundations; Future; Goals; HIV; HIV Infections; HIV Protease; HIV Protease Inhibitors; HIV resistance; HIV-1; HIV-1 protease; Impairment; Infection; Investigation; Lead; Length; Ligands; Ligase; Mediating; Membrane; Modality; Modeling; Molecular Conformation; Multi-Drug Resistance; Mutation; Nuclear; Nuclear Envelope; Organic Synthesis; Patients; Peptide Hydrolases; Pharmaceutical Chemistry; Pharmaceutical Preparations; Pharmacotherapy; Predisposition; Probability; Process; Property; Protease Inhibitor; Proteins; Reagent; Regimen; Resistance; Resistance development; Series; Site; Structure; Testing; Therapeutic; Therapeutic Intervention; Ubiquitination; Variant; Viral; Virion; Work; analog; antimicrobial drug; antiretroviral therapy; assay development; base; combat; design; dimer; drug development; drug discovery; experience; high reward; high risk; in vitro activity; in vivo; inhibitor; lead optimization; membrane assembly; next generation; novel; novel strategies; novel therapeutic intervention; particle; pol Gene Products; pre-exposure prophylaxis; prevent; prospective; prototype; recruit; refractory cancer; resistant strain; screening; simulation; small molecule inhibitor; trend; ubiquitin-protein ligase; viral resistance

PROJECT SUMMARY/ABSTRACT Heterobifunctional targeted protein degraders (TPDs) offer advantages over traditional occupancy-based inhibitors including a unique catalytic mechanism of action (MOA), greater target selectivity, and a reduced probability for resistance development. TPDs are known to effectively target not only cytosolic proteins, but also nuclear and membrane-bound proteins. This therapeutic modality shows great promise for treating drug-resistant cancers and autoimmune diseases but has seen only limited application in antiviral drug discovery. HIV-1 protease (PR) is essential for proteolytic cleavage of Gag and Gag-Pol polyproteins and, thus, virion maturation and infectivity. Gag-Pol forms dynamic dimers at plasma membrane assembly/budding sites, allowing the embedded precursor PR to dimerize as a prerequisite for auto-processing. We identified precursor PR/Gag-Pol as a promising target for protease inhibitor (PI)-based TPDs. The widely used HIV-1 PI, Atazanavir (ATV), is amenable to conjugation with linkers and ubiquitin E3 ligase recruiting ligands to serve as prototype HIV-1 TPDs. Importantly, ATV inhibits activity of mature PR as well as autoprocessing of precursor PR/Gag-Pol during the assembly and budding processes. The OBJECTIVE of this study is to show proof-of-concept that HIV-1 Gag- Pol assembling on the inner leaflet of the plasma membrane can be targeted for aberrant ubiquitination, degradation, and/or inhibition, thereby impairing HIV infectivity. Importantly, due to TPDs’ established MOA, even low-affinity Gag-Pol/TPD interactions are likely to lead to impaired Gag-Pol function. Thus, we pose the HYPOTHESIS that novel ATV-based TPDs will not only augment the inhibition of ATV-sensitive HIV-1 strains compared to ATV, but also exhibit increased and broader biological activity against drug-resistant variants. The objective of AIM 1 is to design and synthesize ATV-based TPDs built on state-of-the-art computational methods and predictive physicochemical properties currently accepted for in vivo active TPDs. Our approach will feature a modular TPD design to establish the appropriate ATV attachment point, E3 ligase recruiter, and length and composition of linker required for HIV-1 Gag-Pol ubiquitination/proteasomal degradation. The goal of AIM 2 is to provide proof-of-concept that ATV-TPDs exert superior activity versus ATV against wild type and PI-resistant HIV-1 strains. We will systematically screen four series of novel ATV-TPD for activity in vitro, in single-round infectivity, and in multi-round replication assays to identify the most promising ATV-TPD candidates. The latter will be tested in complementary limited-scope mechanistic studies, including comparing ATV-TPDs with analogs bearing inactive E3-ligase ligands, to probe if antiviral activity is consistent with the proposed MOA. The IMPACT will be TPDs targeting HIV-1 Gag-Pol and precursor PR that limit infectivity and replication through a mechanism distinct from occupancy-based HIV-1 PI. This will spur the future development of efficacious regimens against PI-resistant HIV strains with reduced susceptibility for resistance development.

项目总结/文摘