SBIR-STTR Award

Combination antiretroviral therapy (cART) in current use is able to suppress HIV-1 to undetectable levels (<50 copies/mL), but unable to eliminate the provirus in latent CD4+ T cells. Thus, patients must remain under cART indefinitely or risk viral rebound if therapy is discontinued. The available anti-HIV drugs do not prevent transcription from provirus nor inhibit viral release from cellular reservoirs. A new class of anti-HIV drugs targeting transcription could buttress current cART due to its potential to block viral reactivation in latently infected CD4+ T cells, resulting in a state of deep-latency, followed by the continuous decay of this latent pool of cells over time. Eradication of the latent HIV reservoir could be achieved by employing disruptors of HIV’s TAR secondary structure, which would prevent binding of the Tat protein and other host factors required for transcription. We propose to identify small molecules that specifically bind and disrupt the apical loop or side bulge in HIV’s TAR hairpin that result in inhibition of the trans- activation of the viral promoter and virus replication. Vironika LLC has developed new methods and assays to identify small molecules which interact with structured viral RNA. For example, Vironika has developed applications of Homogeneous Time-Resolved Fluorescence (HTRF immunoassay), Alpha Screen (Donor/Acceptor beads) and thermocycler-based Fluorescence Resonance Energy Transfer (FRET), which enable high-throughput screening (HTS) of small molecules to identify inhibitors of HSV and EBV latent infection. Libraries containing novel and proprietary small molecules with potential for new medicinal chemistry will be screened using an RNA probe representing the TAR hairpin. Cell-based assays will be used to investigate the antiviral activity of selected hit compounds. The product that ultimately results from this proposal is a small molecule that selectively binds and disrupts the secondary structure of HIV’s TAR, thereby inhibiting the binding of TAT and/or P-TEFb which are required for viral expression. Safe, efficacious, small molecule agents targeting HIV TAR/Tat or TAR/P-TEFb interaction would inevitably change current clinical practice and possibly enable global control of this disease. Public Health Relevance Statement Project NarrativeThis SBIR proposal addresses a critical need for therapeutics to supplement combination antiretroviral therapy (cART). The significance of this proposal to human health will be the development of a new therapy which could lead to a functional cure of HIV disease. Eradication of the latent HIV reservoir could be achieved via inhibition of the interaction between the Tat protein, P-TEFb and the Transactivation Response (TAR) hairpin. We propose to identify small molecules that specifically bind and disrupt the apical loop or side bulge in HIV’s TAR hairpin that result in inhibition of the trans-activation of the viral promoter and virus replication.

Project Terms:
Acquired Immunodeficiency Syndrome ; AIDS ; Acquired Immune Deficiency ; Acquired Immune Deficiency Syndrome ; Acquired Immuno-Deficiency Syndrome ; Acquired Immunologic Deficiency Syndrome ; inhibitor/antagonist ; inhibitor ; Antiviral Agents ; Antiviral Drugs ; Antivirals ; anti-viral agents ; anti-viral drugs ; anti-virals ; Biological Assay ; Assay ; Bioassay ; Biologic Assays ; Malignant Neoplasms ; Cancers ; Malignant Tumor ; malignancy ; neoplasm/cancer ; Cell Culture Techniques ; cell culture ; Cells ; Cell Body ; Pharmaceutical Chemistry ; Medicinal Chemistry ; Pharmaceutic Chemistry ; Disease ; Disorder ; Fluorescence ; Foxes ; Goals ; Health ; HIV ; AIDS Virus ; Acquired Immune Deficiency Syndrome Virus ; Acquired Immunodeficiency Syndrome Virus ; Human Immunodeficiency Viruses ; LAV-HTLV-III ; Lymphadenopathy-Associated Virus ; Virus-HIV ; HIV Infections ; HTLV-III Infections ; HTLV-III-LAV Infections ; Human T-Lymphotropic Virus Type III Infections ; HIV-1 ; HIV-I ; HIV1 ; Human Immunodeficiency Virus Type 1 ; Human immunodeficiency virus 1 ; Human ; Modern Man ; Immunoassay ; Lead ; Pb element ; heavy metal Pb ; heavy metal lead ; Libraries ; Ligands ; Methods ; United States National Institutes of Health ; NIH ; National Institutes of Health ; Patients ; Drug Kinetics ; Pharmacokinetics ; Proviruses ; Risk ; RNA ; Non-Polyadenylated RNA ; RNA Gene Products ; Ribonucleic Acid ; RNA Probes ; RNA Gene Probes ; viral RNA ; virus RNA ; Specificity ; CD4 Positive T Lymphocytes ; CD4 Cells ; CD4 T cells ; CD4 helper T cell ; CD4 lymphocyte ; CD4+ T-Lymphocyte ; CD4-Positive Lymphocytes ; T4 Cells ; T4 Lymphocytes ; tat Protein ; Trans-Activation of Transcription Protein ; Trans-Activator of Transcription of HIV ; Transactivating Regulatory Protein ; Time ; Transactivation ; trans-activation ; Genetic Transcription ; Gene Transcription ; RNA Expression ; Transcription ; Viremia ; viraemia ; viral sepsis ; virusemia ; virology ; Virus Activation ; Virus Induction ; viral activation ; viral induction ; Virus Replication ; viral multiplication ; viral replication ; virus multiplication ; promoter ; promotor ; base ; Apical ; Area ; Phase ; Biochemical ; Simplexvirus ; HSV ; Herpes Simplex Virus ; Herpes labialis Virus ; Chemicals ; Failure ; Individual ; Funding ; Integration Host Factors ; Host Factor ; Host Factor Protein ; Therapeutic ; AIDS drugs ; Anti-AIDS Agents ; Anti-AIDS Drugs ; Anti-HIV Drugs ; Anti-Human Immunodeficiency Virus Agents ; antiAIDS agent ; Anti-HIV Agents ; Side ; Viral ; meetings ; experience ; FRET ; Förster Resonance Energy Transfer ; Fluorescence Resonance Energy Transfer ; chemical library ; small molecule libraries ; pharmacophore ; Animal Models and Related Studies ; model of animal ; model organism ; Animal Model ; P-TEFb ; Positive Transcription Elongation Factor B ; tat-Associated Kinase ; Positive Transcriptional Elongation Factor B ; Structure ; novel ; Manpower ; personnel ; Human Resources ; Pharmacodynamics ; Modeling ; Property ; response ; latent infection ; High Throughput Assay ; high throughput screening ; QSAR ; Quantitiative Structure Activity Relationship ; Quantitative Structure-Activity Relationship ; disease control ; disorder control ; RNA bound ; RNA Binding ; Molecular Interaction ; Binding ; preventing ; prevent ; small molecule ; Address ; Small Business Innovation Research Grant ; SBIR ; Small Business Innovation Research ; Small Molecule Chemical Library ; Validation ; Development ; developmental ; antiretroviral therapy ; anti-retroviral therapy ; anti-retroviral treatment ; antiretroviral treatment ; Epstein-Barr Virus latency ; EBV latency ; novel therapeutics ; new drug treatments ; new drugs ; new therapeutics ; new therapy ; next generation therapeutics ; novel drug treatments ; novel drugs ; novel therapy ; clinical practice ; efficacy testing ; screening ; Drug Targeting ; biophysical properties ; biophysical characteristics ; biophysical characterization ; biophysical measurement ; biophysical parameters ; HIV-associated neurocognitive disorder ; HIV 1 associated neurocognitive disorder ; HIV-1 associated neurocognitive disorder ; targeted agent ; small molecule inhibitor ; Structural Protein ; viral rebound ; virus rebound ; lead optimization ; latent HIV reservoir ; latent HIV-1 reservoir ; latent HIV1 reservoir ;

Combination antiretroviral therapy (cART) in current use is able to suppress HIV-1 toundetectable levels (<50 copies/mL), but unable to eliminate the provirus in latent CD4+ T cells.Thus, patients must remain under cART indefinitely or risk viral rebound if therapy is discontinued.The available anti-HIV drugs do not prevent transcription from provirus nor inhibit viral releasefrom cellular reservoirs. A new class of anti-HIV drugs targeting transcription could buttresscurrent cART due to its potential to block viral reactivation in latently infected CD4+ T cells,resulting in a state of deep-latency, followed by the continuous decay of this latent pool of cellsover time. Eradication of the latent HIV reservoir could be achieved by employing disruptors ofHIV's TAR secondary structure, which would prevent binding of the Tat protein and other hostfactors required for transcription. We propose to identify small molecules that specifically bindand disrupt the apical loop or side bulge in HIV's TAR hairpin that result in inhibition of the trans-activation of the viral promoter and virus replication. Vironika LLC has developed new methodsand assays to identify small molecules which interact with structured viral RNA. For example,Vironika has developed applications of Homogeneous Time-Resolved Fluorescence (HTRFimmunoassay), Alpha Screen (Donor/Acceptor beads) and thermocycler-based FluorescenceResonance Energy Transfer (FRET), which enable high-throughput screening (HTS) of smallmolecules to identify inhibitors of HSV and EBV latent infection. Libraries containing novel andproprietary small molecules with potential for new medicinal chemistry will be screened using anRNA probe representing the TAR hairpin. Cell-based assays will be used to investigate the antiviralactivity of selected hit compounds. The product that ultimately results from this proposal is asmall molecule that selectively binds and disrupts the secondary structure of HIV's TAR, therebyinhibiting the binding of TAT and/or P-TEFb which are required for viral expression. Safe,efficacious, small molecule agents targeting HIV TAR/Tat or TAR/P-TEFb interaction wouldinevitably change current clinical practice and possibly enable global control of this disease.

Public Health Relevance Statement:
Project Narrative This SBIR proposal addresses a critical need for therapeutics to supplement combination antiretroviral therapy (cART). The significance of this proposal to human health will be the development of a new therapy which could lead to a functional cure of HIV disease. Eradication of the latent HIV reservoir could be achieved via inhibition of the interaction between the Tat protein, P-TEFb and the Transactivation Response (TAR) hairpin. We propose to identify small molecules that specifically bind and disrupt the apical loop or side bulge in HIV's TAR hairpin that result in inhibition of the trans-activation of the viral promoter and virus replication.

Project Terms: