Hepatitis C Virus (HCV) infects approximately 4 million Americans and 170 million people on a worldwide basis. Despite substantial reductions in blood product-related transmission over the past two decades, especially in resourced settings, transmission among injecting drug users continues and there is increasing evidence of transmission among individuals engaged in higher risk sexual behaviors. Furthermore, since most morbidity from the virus is related to chronic liver disease and requires 20 or more years to develop, HCV-related morbidity and mortality is projected to increase in the US for at least the next decade regardless of the current transmission rate. Over the last 10 years there have been steady improvements in therapeutic options with the evolution of pegylated interferon (PEG-Ifn)-ribavirin based treatment regimens. Despite these advances, only about 50% of those with the HCV genotype most common in the US (Genotype 1) who can tolerate a full course of therapy respond fully to PEG-Ifn based therapy. Contraindications and toxicities to components of the current regimen preclude many treatment candidates from initiating or completing a full course of therapy and suggest that substantial further improvement in Ifn-based therapies is unlikely. Over the past 3 years there has been increasing progress in the development of small molecular inhibitors of the HCV NS3/NS4a protease and the NS5b polymerase. Compounds directed at each molecular target have clearly demonstrated proof-of-concept in vivo and combination studies with PEG-Ifn are underway. HCV shares two critical properties with HIV: high replication rates and low replicative fidelity, that make it highly likely that efficacious all small molecular regimens will require the use of multiple agents directed at several molecular targets. As is outlined in this application, two research groups are collaborating to optimize a series of orally active nucleoside phosphonate compounds directed at the HCV polymerase. We have created a series of alkoxyalkyl nucleoside phosphonate derivatives that substantially enhance both the antiviral activity and the pharmacokinetic properties of parent nucleosides. Using an approach that we have successfully employed in drug discovery directed at HIV, poxviruses and herpes viruses we propose to systematically evaluate this approach in the setting of HCV infection with the view that the next substantial advance in HCV therapeutics will likely require the development of interferon-free regimens and that this will require the availability of a much larger array of small molecular HCV inhibitors than is currently in hand.

Public Health Relevance

In this application we propose to construct new compounds that are active against hepatitis C virus, a major cause of liver disease and hepatic cellular carcinoma. Our approach uses novel lipid tails that greatly enhance antiviral activity by concentrating the active component of the molecule within infected cells. If we are successful in these efforts, we believe this class of molecules could greatly improve treatment options for people with HCV infection.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI076558-02
Application #
7786222
Study Section
Drug Discovery and Mechanisms of Antimicrobial Resistance Study Section (DDR)
Program Officer
Koshy, Rajen
Project Start
2009-04-01
Project End
2014-03-31
Budget Start
2010-04-01
Budget End
2011-03-31
Support Year
2
Fiscal Year
2010
Total Cost
$536,480
Indirect Cost
Name
University of California San Diego
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
804355790
City
La Jolla
State
CA
Country
United States
Zip Code
92093
Carlin, Aaron F; Aristizabal, Paula; Song, Qinghua et al. (2015) Temporal dynamics of inflammatory cytokines/chemokines during sofosbuvir and ribavirin therapy for genotype 2 and 3 hepatitis C infection. Hepatology 62:1047-58
Schooley, Robert T (2012) Hepatitis C virus therapeutics: at the end of the beginning. Top Antivir Med 20:17-9
Julien, Olivier; Beadle, James R; Magee, Wendy C et al. (2011) Solution structure of a DNA duplex containing the potent anti-poxvirus agent cidofovir. J Am Chem Soc 133:2264-74
Valiaeva, Nadejda; Wyles, David L; Schooley, Robert T et al. (2011) Synthesis and antiviral evaluation of 9-(S)-[3-alkoxy-2-(phosphonomethoxy)propyl]nucleoside alkoxyalkyl esters: inhibitors of hepatitis C virus and HIV-1 replication. Bioorg Med Chem 19:4616-25
Ray, Adrian S; Hostetler, Karl Y (2011) Application of kinase bypass strategies to nucleoside antivirals. Antiviral Res 92:277-91
Wyles, David L; Schooley, Robert T (2010) Rong's numbers: accelerating progress in HCV therapeutic research. Sci Transl Med 2:33ps25
Wyles, David L; Kaihara, Kelly A; Korba, Brent E et al. (2009) The octadecyloxyethyl ester of (S)-9-[3-hydroxy-2-(phosphonomethoxy) propyl]adenine is a potent and selective inhibitor of hepatitis C virus replication in genotype 1A, 1B, and 2A replicons. Antimicrob Agents Chemother 53:2660-2
Morrey, John D; Korba, Brent E; Beadle, James R et al. (2009) Alkoxyalkyl esters of 9-(s)-(3-hydroxy-2-phosphonomethoxypropyl) adenine are potent and selective inhibitors of hepatitis B virus (HBV) replication in vitro and in HBV transgenic mice in vivo. Antimicrob Agents Chemother 53:2865-70
Hostetler, Karl Y (2009) Alkoxyalkyl prodrugs of acyclic nucleoside phosphonates enhance oral antiviral activity and reduce toxicity: current state of the art. Antiviral Res 82:A84-98