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Virologica Sinica logoLink to Virologica Sinica
. 2010 Jul 28;25(4):246–266. doi: 10.1007/s12250-010-3140-2

Development of novel antiviral therapies for hepatitis C virus

Kai Lin 1,
PMCID: PMC8227914  PMID: 20960299

Abstract

Over 170 million people worldwide are infected with hepatitis C virus (HCV), a major cause of liver diseases. Current interferon-based therapy is of limited efficacy and has significant side effects and more effective and better tolerated therapies are urgently needed. HCV is a positive, single-stranded RNA virus with a 9.6 kb genome that encodes ten viral proteins. Among them, the NS3 protease and the NS5B polymerase are essential for viral replication and have been the main focus of drug discovery efforts. Aided by structure-based drug design, potent and specific inhibitors of NS3 and NS5B have been identified, some of which are in late stage clinical trials and may significantly improve current HCV treatment. Inhibitors of other viral targets such as NS5A are also being pursued. However, HCV is an RNA virus characterized by high replication and mutation rates and consequently, resistance emerges quickly in patients treated with specific antivirals as monotherapy. A complementary approach is to target host factors such as cyclophilins that are also essential for viral replication and may present a higher genetic barrier to resistance. Combinations of these inhibitors of different mechanism are likely to become the essential components of future HCV therapies in order to maximize antiviral efficacy and prevent the emergence of resistance.

Key words: HCV, Hepatitis, Antiviral, Polymerase, Cyclophilin

References

  • 1.Ago H., Adachi T., Yoshida A., et al. Crystal structure of the RNA-dependent RNA polymerase of hepatitis C virus. Structure. 1999;7:1417–1426. doi: 10.1016/S0969-2126(00)80031-3. [DOI] [PubMed] [Google Scholar]
  • 2.Arasappan A, Bennett F, Bogen S L, et al. 2010. Discovery of Narlaprevir (SCH 900518): a potent, second generation HCV NS3 serine protease inhibitor. ACS Med Chem Lett, 2-15-2010 [DOI] [PMC free article] [PubMed]
  • 3.Bain V. G., Kaita K. D., Marotta P., et al. Safety and antiviral activity of albinterferon alfa-2b dosed every four weeks in genotype 2/3 chronic hepatitis C patients. Clin Gastroenterol Hepatol. 2008;6:701–706. doi: 10.1016/j.cgh.2008.02.056. [DOI] [PubMed] [Google Scholar]
  • 4.Bartenschlager R., Ahlborn-Laake L., Mous J., et al. Nonstructural protein 3 of the hepatitis C virus encodes a serine-type proteinase required for cleavage at the NS3/4 and NS4/5 junctions. J Virol. 1993;67:3835–3844. doi: 10.1128/jvi.67.7.3835-3844.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 5.Bartosch B., Dubuisson J., Cosset F. L. Infectious hepatitis C virus pseudo-particles containing functional E1–E2 envelope protein complexes. J Exp Med. 2003;197:633–642. doi: 10.1084/jem.20021756. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 6.Bavisotto L, Wang C, Jacobson I, et al. 2007. Antiviral, pharmacokinetic and safety data for GS-9190, a non-nucleoside HCV NS5B polymerase inhibitor, in a phase-1 trial in HCV genotype 1 infected patients. 58th Annual Meeting of the American Association for the Study of Liver Diseases, Boston, MA.
  • 7.Bernstein B, Menon R M, Klein C E, et al. 2009. Pharmacokinetics, safety and tolerability of the HCV protease inhibitor ABT-450 with ritonavir following multiple ascending doses in healthy adult volunteers. HepDART 2009, Kohala Coast, Hawaii, USA.
  • 8.Blight K. J., Kolykhalov A. A., Rice C. M. Efficient initiation of HCV RNA replication in cell culture. Science. 2000;290:1972–1974. doi: 10.1126/science.290.5498.1972. [DOI] [PubMed] [Google Scholar]
  • 9.Borawski J., Troke P., Puyang X., et al. Class III phosphatidylinositol 4-kinase alpha and beta are novel host factor regulators of hepatitis C virus replication. J Virol. 2009;83:10058–10074. doi: 10.1128/JVI.02418-08. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 10.Borowski P., Deinert J., Schalinski S., et al. Halogenated benzimidazoles and benzotriazoles as inhibitors of the NTPase/helicase activities of hepatitis C and related viruses. Eur J Biochem. 2003;270:1645–1653. doi: 10.1046/j.1432-1033.2003.03540.x. [DOI] [PubMed] [Google Scholar]
  • 11.Borowski P., Lang M., Haag A., et al. Tropolone and its derivatives as inhibitors of the helicase activity of hepatitis C virus nucleotide triphosphatase/helicase. Antivir Chem Chemother. 2007;18:103–109. doi: 10.1177/095632020701800206. [DOI] [PubMed] [Google Scholar]
  • 12.Brainard D M, Anderson M S, Petry A S, et al. 2009. Safety and antiviral activity of NS5B polymerase inhibitor MK-3281in genotype 1 and 3 HCV-infected patients. 60th Annual Meeting of the American Association for the Study of Liver Diseases, Boston, MA.
  • 13.Bressanelli S., Tomei L., Roussel A., et al. Crystal structure of the RNA-dependent RNA polymerase of hepatitis C virus. Proc Natl Acad Sci USA. 1999;96:13034–13039. doi: 10.1073/pnas.96.23.13034. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 14.Bukh J. A critical role for the chimpanzee model in the study of hepatitis C. Hepatology. 2004;39:1469–1475. doi: 10.1002/hep.20268. [DOI] [PubMed] [Google Scholar]
  • 15.Chatterji U, Bobardt M, Lim P, et al. 2010. Cyclophilin A-Independent Recruitment of NS5A and NS5B Into HCV Replication Complexes. J Gen Virol, In press. [DOI] [PMC free article] [PubMed]
  • 16.Chatterji U., Bobardt M., Selvarajah S., et al. The isomerase active site of cyclophilin A is critical for HCV replication. J Biol Chem. 2009;284:16998–17005. doi: 10.1074/jbc.M109.007625. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 17.Chatterji U., Bobardt M., Selvarajah S., et al. The isomerase active site of cyclophilin A is critical for hepatitis C virus replication. J Biol Chem. 2009;284:16998–17005. doi: 10.1074/jbc.M109.007625. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 18.Chen C. M., He Y., Lu L., et al. Activity of a potent hepatitis C virus polymerase inhibitor in the chimpanzee model. Antimicrob Agents Chemother. 2007;51:4290–4296. doi: 10.1128/AAC.00723-07. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 19.Cho N. J., Dvory-Sobol H., Lee C., et al. Identification of a class of HCV inhibitors directed against the nonstructural protein NS4B. Science Translational Medicine. 2010;2:1–8. doi: 10.1126/scitranslmed.3000331. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 20.Choo Q. L., Kuo G., Weiner A. J., et al. Isolation of a cDNA clone derived from a blood-borne non-A, non-B viral hepatitis genome. Science. 1989;244:359–362. doi: 10.1126/science.2523562. [DOI] [PubMed] [Google Scholar]
  • 21.Ciesek S., Steinmann E., Wedemeyer H., et al. Cyclosporine A inhibits hepatitis C virus nonstructural protein 2 through cyclophilin A. Hepatology. 2009;50:1638–1645. doi: 10.1002/hep.23281. [DOI] [PubMed] [Google Scholar]
  • 22.Clinicaltrials.gov.http://clinicaltrials.gov/.
  • 23.Coelmont L., Kaptein S., Paeshuyse J., et al. Debio 025, a cyclophilin binding molecule, is highly efficient in clearing hepatitis C virus (HCV) replicon-containing cells when used alone or in combination with specifically targeted antiviral therapy for HCV (STAT-C) inhibitors. Antimicrob Agents Chemother. 2009;53:967–976. doi: 10.1128/AAC.00939-08. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 24.Colonno R. Discovery and characterization of PPI-461, a potent and selective HCV NS5A inhibitor with broad-spectrum coverage of all HCV genotypes. San Diego, CA: HCV Drug Discovery; 2010. [Google Scholar]
  • 25.Cooper C., Lawitz E. J., Ghali P., et al. Evaluation of VCH-759 monotherapy in hepatitis C infection. J Hepatol. 2009;51(1):39–46. doi: 10.1016/j.jhep.2009.03.015. [DOI] [PubMed] [Google Scholar]
  • 26.Darke P. L., Jacobs A. R., Waxman L., et al. Inhibition of hepatitis C virus NS2/3 processing by NS4A peptides. Implications for control of viral processing. J Biol Chem. 1999;274:34511–34514. doi: 10.1074/jbc.274.49.34511. [DOI] [PubMed] [Google Scholar]
  • 27.Einav S., Gerber D., Bryson P. D., et al. Discovery of a hepatitis C target and its pharmacological inhibitors by microfluidic affinity analysis. Nat Biotechnol. 2008;26:1019–1027. doi: 10.1038/nbt.1490. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 28.Elazar M., Liu M., McKenna S. A., et al. The anti-hepatitis C agent nitazoxanide induces phosphorylation of eukaryotic initiation factor 2alpha via protein kinase activated by double-stranded RNA activation. Gastroenterology. 2009;137:1827–1835. doi: 10.1053/j.gastro.2009.07.056. [DOI] [PubMed] [Google Scholar]
  • 29.Erhardt A., Deterding K., Benhamou Y., et al. Safety, pharmacokinetics and antiviral effect of BILB 1941, a novel hepatitis C virus RNA polymerase inhibitor, after 5 days oral treatment. Antivir Ther. 2009;14:23–32. [PubMed] [Google Scholar]
  • 30.Evans M. J., von H. T., Tscherne D. M., et al. Claudin-1 is a hepatitis C virus co-receptor required for a late step in entry. Nature. 2007;446:801–805. doi: 10.1038/nature05654. [DOI] [PubMed] [Google Scholar]
  • 31.Feldstein A., Kleiner D., Kravetz D., et al. Severe hepatocellular injury with apoptosis induced by a hepatitis C polymerase inhibitor. J Clin Gastroenterol. 2009;43:374–381. doi: 10.1097/MCG.0b013e318178d91f. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 32.Fernandes F., Poole D. S., Hoover S., et al. Sensitivity of hepatitis C virus to cyclosporine A depends on nonstructural proteins NS5A and NS5B. Hepatology. 2007;46:1026–1033. doi: 10.1002/hep.21809. [DOI] [PubMed] [Google Scholar]
  • 33.Firbas C., Boehm T., Buerger V., et al. Immunogenicity and safety of different injection routes and schedules of IC41, a Hepatitis C virus (HCV) peptide vaccine. Vaccine. 2010;28:2397–2407. doi: 10.1016/j.vaccine.2009.12.072. [DOI] [PubMed] [Google Scholar]
  • 34.Firbas C., Jilma B., Tauber E., et al. Immunogenicity and safety of a novel therapeutic hepatitis C virus (HCV) peptide vaccine: a randomized, placebo controlled trial for dose optimization in 128 healthy subjects. Vaccine. 2006;24:4343–4353. doi: 10.1016/j.vaccine.2006.03.009. [DOI] [PubMed] [Google Scholar]
  • 35.Flisiak R., Feinman S. V., Jablkowski M., et al. The cyclophilin inhibitor Debio 025 combined with PEG IFNalpha2a significantly reduces viral load in treatment-naive hepatitis C patients. Hepatology. 2009;49:1460–1468. doi: 10.1002/hep.22835. [DOI] [PubMed] [Google Scholar]
  • 36.Flisiak R., Feinman S. V., Jablkowski M., et al. The cyclophilin inhibitor Debio 025 combined with PEG IFNalpha2a significantly reduces viral load in treatment-naive hepatitis C patients. Hepatology. 2009;49:1460–1468. doi: 10.1002/hep.22835. [DOI] [PubMed] [Google Scholar]
  • 37.Flisiak R., Horban A., Gallay P., et al. The cyclophilin inhibitor Debio-025 shows potent anti-hepatitis C effect in patients coinfected with hepatitis C and human immunodeficiency virus. Hepatology. 2008;47:817–826. doi: 10.1002/hep.22131. [DOI] [PubMed] [Google Scholar]
  • 38.Forestier N., Reesink H. W., Weegink C. J., et al. Antiviral activity of telaprevir (VX-950) and peginterferon alfa-2a in patients with hepatitis C. Hepatology. 2007;46:640–648. doi: 10.1002/hep.21774. [DOI] [PubMed] [Google Scholar]
  • 39.Fried M., Shiffman M. L., Reddy K. R., et al. Peginterferon alfa-2a plus ribavirin for chronic hepatitis C virus infection. N Engl J Med. 2002;347:975–982. doi: 10.1056/NEJMoa020047. [DOI] [PubMed] [Google Scholar]
  • 40.Gaither L. A., Borawski J., Anderson L. J., et al. Multiple cyclophilins involved in different cellular pathways mediate HCV replication. Virology. 2010;397:43–55. doi: 10.1016/j.virol.2009.10.043. [DOI] [PubMed] [Google Scholar]
  • 41.Gane E. J., Oberts S. K., Tedman C., et al. First-in-man demonstration of potent antiviral activity with a nucleoside polymerase (R7128) and protease (R7227/ITMN-191) inhibitor combination in HCV: safety, pharmacokinetics, and virologic results from INFORM-1. J Hepatol. 2009;50(Suppl.1):S380. doi: 10.1016/S0168-8278(09)61048-5. [DOI] [Google Scholar]
  • 42.Gane E J, Roberts S K, Stedman C, et al. 2009. First-in-man demonstration of potent antiviral activity with a nucleoside polymerase (R7128) and protease (R7227/ITMN-191) inhibitor combination in HCV: Safety, pharmacokinetics, and virologic results from INFORM-1. 44thAnnual Meeting of the European Association for the Study of the Liver. Copenhagen, Denmark.
  • 43.Goto K., Watashi K., Inoue D., et al. Identification of cellular and viral factors related to anti-hepatitis C virus activity of cyclophilin inhibitor. Cancer Sci. 2009;100:1943–1950. doi: 10.1111/j.1349-7006.2009.01263.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 44.Gozdek A., Zhukov I., Polkowska A., et al. NS3 Peptide, a novel potent hepatitis C virus NS3 helicase inhibitor: its mechanism of action and antiviral activity in the replicon system. Antimicrob Agents Chemother. 2008;52:393–401. doi: 10.1128/AAC.00961-07. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 45.Grakoui A., McCourt D. W., Wychowski C., et al. A second hepatitis C virus-encoded proteinase. Proc Natl Acad Sci USA. 1993;90:10583–10587. doi: 10.1073/pnas.90.22.10583. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 46.Griffin S., StGelais C., Owsianka A. M., et al. Genotype-dependent sensitivity of hepatitis C virus to inhibitors of the p7 ion channel. Hepatology. 2008;48:1779–1790. doi: 10.1002/hep.22555. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 47.Griffin S. D., Beales L. P., Clarke D. S., et al. The p7 protein of hepatitis C virus forms an ion channel that is blocked by the antiviral drug, Amantadine. FEBS Lett. 2003;535:34–38. doi: 10.1016/S0014-5793(02)03851-6. [DOI] [PubMed] [Google Scholar]
  • 48.Habersetzer F., Baumert T. F., Stoll-Keller F. GI-5005, a yeast vector vaccine expressing an NS3-core fusion protein for chronic HCV infection. Curr Opin Mol Ther. 2009;11:456–462. [PubMed] [Google Scholar]
  • 49.Hanoulle X., Badillo A., Wieruszeski J. M., et al. Hepatitis C virus NS5A protein is a substrate for the Peptidyl-Prolyl cis/trans isomerase activity of Cyclophilins A and B. J Biol Chem. 2009;284(20):13589–13601. doi: 10.1074/jbc.M809244200. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 50.Heck J. A., Meng X., Frick D. N. Cyclophilin B stimulates RNA synthesis by the HCV RNA dependent RNA polymerase. Biochem Pharmacol. 2009;77:1173–1180. doi: 10.1016/j.bcp.2008.12.019. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 51.Hendricks R. T., Fell J. B., Blake J. F., et al. Non-nucleoside inhibitors of HCV NS5B polymerase. Part 1: Synthetic and computational exploration of the binding modes of benzothiadiazine and 1,4-benzothiazine HCV NS5b polymerase inhibitors. Bioorg Med Chem Lett. 2009;19:3637–3641. doi: 10.1016/j.bmcl.2009.04.119. [DOI] [PubMed] [Google Scholar]
  • 52.Hezode C., Forestier N., Dusheiko G., et al. Telaprevir and peginterferon with or without ribavirin for chronic HCV infection. N Engl J Med. 2009;360:1839–1850. doi: 10.1056/NEJMoa0807650. [DOI] [PubMed] [Google Scholar]
  • 53.Hinrichsen H., Benhamou Y., Wedemeyer H., et al. Short-term antiviral efficacy of BILN 2061, a hepatitis C virus serine protease inhibitor, in hepatitis C genotype 1 patients. Gastroenterology. 2004;127:1347–1355. doi: 10.1053/j.gastro.2004.08.002. [DOI] [PubMed] [Google Scholar]
  • 54.Hopkins S., Heuman D., Gavis E., et al. Safety, plasma pharmacokinetics, and anti-viral activity of SCY-635 in adult patients with chronic hepatitis C virus infection. J Hepatol. 2009;50(Suppl.1):S36. doi: 10.1016/S0168-8278(09)60091-X. [DOI] [Google Scholar]
  • 55.Hopkins S., Scorneaux B., Huang Z., et al. SCY-635, a novel nonimmunosuppressive analog of cyclosporine that exhibits potent inhibition of hepatitis C virus RNA replication in vitro. Antimicrob Agents Chemother. 2010;54:660–672. doi: 10.1128/AAC.00660-09. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 56.Horsmans Y., Berg T., Desager J. P., et al. Isatoribine, an agonist of TLR7, reduces plasma virus concentration in chronic hepatitis C infection. Hepatology. 2005;42:724–731. doi: 10.1002/hep.20839. [DOI] [PubMed] [Google Scholar]
  • 57.Howe A. Y., Cheng H., Johann S., et al. Molecular mechanism of hepatitis C virus replicon variants with reduced susceptibility to a benzofuran inhibitor, HCV-796. Antimicrob Agents Chemother. 2008;52:3327–3338. doi: 10.1128/AAC.00238-08. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 58.Hsu M., Zhang J., Flint M., et al. Hepatitis C virus glycoproteins mediate pH-dependent cell entry of pseudotyped retroviral particles. Proc Natl Acad Sci USA. 2003;100:7271–7276. doi: 10.1073/pnas.0832180100. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 59.Jirasko V., Montserret R., Appel N., et al. Structural and functional characterization of nonstructural protein 2 for its role in hepatitis C virus assembly. J Biol Chem. 2008;283:28546–28562. doi: 10.1074/jbc.M803981200. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 60.Jones C. T., Murray C. L., Eastman D. K., et al. Hepatitis C virus p7 and NS2 proteins are essential for production of infectious virus. J Virol. 2007;81:8374–8383. doi: 10.1128/JVI.00690-07. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 61.Kaita K., Yoshida E., Kunimoto D., et al. Ph II proof of concept study of celgosivir in combination with peginterferon alfa-2b and ribavirin in chronic hepatitis C genotype 1 non-responder patients. J Hepatol. 2007;46(Suppl.1):S56. doi: 10.1016/S0168-8278(07)61725-5. [DOI] [Google Scholar]
  • 62.Kaul A., Stauffer S., Berger C., et al. Essential role of cyclophilin A for hepatitis C virus replication and virus production and possible link to polyprotein cleavage kinetics. PLoS Pathog. 2009;5(8):e1000546. doi: 10.1371/journal.ppat.1000546. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 63.Khoury G., Ewart G., Luscombe C., et al. Antiviral efficacy of the novel compound BIT225 against HIV-1 release from human macrophages. Antimicrob Agents Chemother. 2010;54:835–845. doi: 10.1128/AAC.01308-09. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 64.Kim J. L., Morgenstern K. A., Lin C., et al. Crystal structure of the hepatitis C virus NS3 protease domain complexed with a synthetic NS4A cofactor peptide. Cell. 1996;87:343–355. doi: 10.1016/S0092-8674(00)81351-3. [DOI] [PubMed] [Google Scholar]
  • 65.Klade C. S., Wedemeyer H., Berg T., et al. Therapeutic vaccination of chronic hepatitis C nonresponder patients with the peptide vaccine IC41. Gastroenterology. 2008;134:1385–1395. doi: 10.1053/j.gastro.2008.02.058. [DOI] [PubMed] [Google Scholar]
  • 66.Korba B. E., Montero A. B., Farrar K., et al. Nitazoxanide, tizoxanide and other thiazolides are potent inhibitors of hepatitis B virus and hepatitis C virus replication. Antiviral Res. 2008;77:56–63. doi: 10.1016/j.antiviral.2007.08.005. [DOI] [PubMed] [Google Scholar]
  • 67.Kwo P., Lawitz E., McCone J., et al. HCV SPRINT-1 final results: SVR 24 from a phase 2 study of boceprevir plus Pegintron™ (peginterferon alfa-2b)/ribavirin in treatment-naive subjects with genotype-1 chronic hepatitis C. J Hepatol. 2009;50(Suppl.1):S4. doi: 10.1016/S0168-8278(09)60006-4. [DOI] [Google Scholar]
  • 68.Lalezari J, Asmuth D, Casiro A, et al. 2009. Antiviral activity, safety and pharmacokinetics of IDX184, a liver-targeted nucleotide HCV polymerase inhibitor, in patients with chronic hepatitis C. 60th Annual Meeting of the American Association for the Study of Liver Diseases, Boston, MA.
  • 69.Lamarre D., Anderson P. C., Bailey M., et al. An NS3 protease inhibitor with antiviral effects in humans infected with hepatitis C virus. Nature. 2003;426:186–189. doi: 10.1038/nature02099. [DOI] [PubMed] [Google Scholar]
  • 70.Landro J. A., Raybuck S. A., Luong Y. P., et al. Mechanistic role of an NS4A peptide cofactor with the truncated NS3 protease of hepatitis C virus: elucidation of the NS4A stimulatory effect via kinetic analysis and inhibitor mapping. Biochemistry. 1997;36:9340–9348. doi: 10.1021/bi963054n. [DOI] [PubMed] [Google Scholar]
  • 71.Larrey D., Benhamou Y., Lohse A. W., et al. Safety, pharmacokinetics and antiviral effect of BI 207127, a novel HCV RNA polymerase inhibitor, after 5 days oral treatment in patients with chronic hepatitis C. J Hepatol. 2010;50(Suppl.1):S383–S4. [Google Scholar]
  • 72.Lawitz E, Rouzier R, Nguyen, et al. 2009. Safety and antiviral efficacy of 14 days of the cyclophilin inhibitor NIM811 in combination with pegylated interferon α2A in relapsed genotype 1 HCV infected patients. 44thAnnual Meeting of the European Association for the Study of the Liver. Boston, MA.
  • 73.Lawitz E., Cooper C., Rodriguez-Torres M., et al. Safety, tolerability and antiviral activity of VCH-916, a novel non-nucleoside hcv polymerase inhibitor in patients with chronic HCV genotype-1 infection. J Hepatol. 2009;50(Suppl.1):S37. doi: 10.1016/S0168-8278(09)60094-5. [DOI] [Google Scholar]
  • 74.Lawitz E., Rodriguez-Torres M., DeMicco M., et al. Antiviral activity of ANA598, a potent non-nucleoside polymerase inhibitor, in chronic hepatitis C patients. J Hepatol. 2009;50(Suppl.1):S384. doi: 10.1016/S0168-8278(09)61057-6. [DOI] [Google Scholar]
  • 75.Lemm J. A., O’Boyle D., Liu M., et al. Identification of hepatitis C virus NS5A inhibitors. J Virol. 2010;84:482–491. doi: 10.1128/JVI.01360-09. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 76.Lesburg C. A., Cable M. B., Ferrari E., et al. Crystal structure of the RNA-dependent RNA polymerase from hepatitis C virus reveals a fully encircled active site. Nat Struct Biol. 1999;6:937–943. doi: 10.1038/13305. [DOI] [PubMed] [Google Scholar]
  • 77.Li Q., Brass A. L., Ng A., et al. A genome-wide genetic screen for host factors required for hepatitis C virus propagation. Proc Natl Acad Sci USA. 2009;106:16410–16415. doi: 10.1073/pnas.0907439106. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 78.Lin K., Perni R. B., Kwong A. D., et al. VX-950, a novel hepatitis C virus (HCV) NS3-4A protease inhibitor, exhibits potent antiviral activities in HCv replicon cells. Antimicrob Agents Chemother. 2006;50:1813–1822. doi: 10.1128/AAC.50.5.1813-1822.2006. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 79.Lin T. I., Lenz O., Fanning G., et al. In vitro activity and preclinical profile of TMC435350, a potent hepatitis C virus protease inhibitor. Antimicrob Agents Chemother. 2009;53:1377–1385. doi: 10.1128/AAC.01058-08. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 80.Lindenbach B. D., Evans M. J., Syder A. J., et al. Complete replication of hepatitis C virus in cell culture. Science. 2005;309:623–626. doi: 10.1126/science.1114016. [DOI] [PubMed] [Google Scholar]
  • 81.Liu Z, Yang F, Robotham J M, et al. 2009. A Critical Role of Cyclophilin A and its Prolyl-Peptidyl Isomerase Activity in the Structure and Function of the HCV Replication Complex. J Virol, doi: JVI.02550-08 [DOI] [PMC free article] [PubMed]
  • 82.Liverton N. J., Carroll S. S., Dimuzio J., et al. MK-7009, a potent and selective inhibitor of hepatitis C virus NS3/4A protease. Antimicrob Agents Chemother. 2010;54:305–311. doi: 10.1128/AAC.00677-09. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 83.Llinas-Brunet M., Bailey M., Fazal G., et al. Peptide-based inhibitors of the hepatitis C virus serine protease. Bioorg Med Chem Lett. 1998;8:1713–1718. doi: 10.1016/S0960-894X(98)00299-6. [DOI] [PubMed] [Google Scholar]
  • 84.Lohmann V., Korner F., Koch J., et al. Replication of subgenomic hepatitis C virus RNAs in a hepatoma cell line. Science. 1999;285:110–113. doi: 10.1126/science.285.5424.110. [DOI] [PubMed] [Google Scholar]
  • 85.Love R. A., Brodsky O., Hickey M. J., et al. Crystal structure of a novel dimeric form of NS5A domain I protein from hepatitis C virus. J Virol. 2009;83:4395–4403. doi: 10.1128/JVI.02352-08. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 86.Love R. A., Parge H. E., Wickersham J. A., et al. The crystal structure of hepatitis C virus NS3 proteinase reveals a trypsin-like fold and a structural zinc binding site. Cell. 1996;87:331–342. doi: 10.1016/S0092-8674(00)81350-1. [DOI] [PubMed] [Google Scholar]
  • 87.Luik P., Chew C., Aittoniemi J., et al. The 3-dimensional structure of a hepatitis C virus p7 ion channel by electron microscopy. Proc Natl Acad Sci USA. 2009;106:12712–12716. doi: 10.1073/pnas.0905966106. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 88.Luscombe C A, Huang Z, Murray M G, et al. 2010. A novel Hepatitis C virus p7 ion channel inhibitor, BIT225, inhibits bovine viral diarrhea virus in vitro and shows synergism with recombinant interferon-alpha-2b and nucleoside analogues. Antiviral Res, doi:S0166-3542 (10) 00341-00344. [DOI] [PubMed]
  • 89.Ma S., Boerner J. E., TiongYip C., et al. NIM811, a cyclophilin inhibitor, exhibits potent in vitro activity against hepatitis C virus alone or in combination with alpha interferon. Antimicrob Agents Chemother. 2006;50:2976–2982. doi: 10.1128/AAC.00310-06. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 90.Malcolm B. A., Liu R., Lahser F., et al. SCH 503034, a mechanism-based inhibitor of hepatitis C virus NS3 protease, suppresses polyprotein maturation and enhances the antiviral activity of alpha interferon in replicon cells. Antimicrob Agents Chemother. 2006;50:1013–1020. doi: 10.1128/AAC.50.3.1013-1020.2006. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 91.Manns M., Bourliere M., Benhamou Y., et al. Safety and antiviral activity of BI201335, a new HCV NS3 protease inhibitor, in combination therapy with peginterferon alfa 2a (P) and ribavirin (R) for 28 days in P+R treatment-experienced patients with chronic hepatitis C genotype-1 infection. Hepatology. 2008;48(Suppl.1):1151A. [Google Scholar]
  • 92.Manns M., Bourliere M., Benhamou Y., et al. Safety and antiviral activity of BI201335, a new HCV NS3 protease inhibitor, in treatment-naive patients with chronic hepatitis C genotype 1 infection given as monotherapy and in combination with peginterferon alfa-2a (P) and ribavirin (R) Hepatology. 2008;48(Suppl.1):1133A. [Google Scholar]
  • 93.Manns M., Muir A., Adda N., et al. Telaprevir in hepatitis C genotype-1-infected patients with prior non-response, viral breakthrough or relapse to peginterferon-alfa-2a/b and ribavirin therapy: SVR results of the PROVE 3 study. J Hepatol. 2009;50(Supp.1):S379. doi: 10.1016/S0168-8278(09)61046-1. [DOI] [Google Scholar]
  • 94.Manns M. P., McHutchison J. G., Gordon S. C., et al. Peginterferon alfa-2b plus ribavirin compared with interferon alfa-2b plus ribavirin for initial treatment of chronic hepatitis C: a randomised trial. Lancet. 2001;358:958–965.. doi: 10.1016/S0140-6736(01)06102-5. [DOI] [PubMed] [Google Scholar]
  • 95.Mathy J. E., Ma S., Compton T., et al. Combinations of cyclophilin inhibitor NIM811 with hepatitis C Virus NS3-4A Protease or NS5B polymerase inhibitors enhance antiviral activity and suppress the emergence of resistance. Antimicrob Agents Chemother. 2008;52:3267–3275. doi: 10.1128/AAC.00498-08. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 96.McCown M. F., Rajyaguru S., Le P. S., et al. The hepatitis C virus replicon presents a higher barrier to resistance to nucleoside analogs than to nonnucleoside polymerase or protease inhibitors. Antimicrob Agents Chemother. 2008;52:1604–1612. doi: 10.1128/AAC.01317-07. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 97.McHutchison J. G., Everson G. T., Gordon S. C., et al. Telaprevir with peginterferon and ribavirin for chronic HCV genotype 1 infection. N Engl J Med. 2009;360:1827–1838. doi: 10.1056/NEJMoa0806104. [DOI] [PubMed] [Google Scholar]
  • 98.Mercer D. F., Schiller D. E., Elliott J. F., et al. Hepatitis C virus replication in mice with chimeric human livers. Nat.Med. 2001;7:927–933. doi: 10.1038/90968. [DOI] [PubMed] [Google Scholar]
  • 99.Nakagawa M., Sakamoto N., Enomoto N., et al. Specific inhibition of hepatitis C virus replication by cyclosporin A. Biochem Biophys Res Commun. 2004;313(1):42–47. doi: 10.1016/j.bbrc.2003.11.080. [DOI] [PubMed] [Google Scholar]
  • 100.Nakagawa M., Sakamoto N., Tanabe Y., et al. Suppression of hepatitis C virus replication by cyclosporin a is mediated by blockade of cyclophilins. Gastroenterology. 2005;129:1031–1041. doi: 10.1053/j.gastro.2005.06.031. [DOI] [PubMed] [Google Scholar]
  • 101.Nelson D. R., Rustgi V., Balan V., et al. Safety and antiviral activity of albinterferon alfa-2b in prior interferon nonresponders with chronic hepatitis C. Clin Gastroenterol Hepatol. 2009;7:212–218. doi: 10.1016/j.cgh.2008.10.035. [DOI] [PubMed] [Google Scholar]
  • 102.Nettles R., Chien C., Chung E., et al. BMS-790052 is a first-in-class potent hepatitis C virus (HCV) NS5A inhibitor for patients with chronic HCV infection: results from a proof-of-concept study. Hepatology. 2008;48(Suppl.1):1025A. [Google Scholar]
  • 103.Neumann A. U., Lam N. P., Dahari H., et al. Hepatitis C viral dynamics in vivo and the antiviral efficacy of interferon-alpha therapy. Science. 1998;282:103–107. doi: 10.1126/science.282.5386.103. [DOI] [PubMed] [Google Scholar]
  • 104.Ng T. I., Mo H., Pilot-Matias T., et al. Identification of host genes involved in hepatitis C virus replication by small interfering RNA technology. Hepatology. 2007;45:1413–1421. doi: 10.1002/hep.21608. [DOI] [PubMed] [Google Scholar]
  • 105.Nguyen T. T., Gates A. T., Gutshall L. L., et al. Resistance profile of a hepatitis C virus RNA-dependent RNA polymerase benzothiadiazine inhibitor. Antimicrob Agents Chemother. 2003;47:3525–3530. doi: 10.1128/AAC.47.11.3525-3530.2003. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 106.Paeshuyse J., Kaul A., De C. E., et al. The non-immunosuppressive cyclosporin DEBIO-025 is a potent inhibitor of hepatitis C virus replication in vitro. Hepatology. 2006;43:761–770. doi: 10.1002/hep.21102. [DOI] [PubMed] [Google Scholar]
  • 107.Paeshuyse J., Kaul A., De C. E., et al. The non-immunosuppressive cyclosporin DEBIO-025 is a potent inhibitor of hepatitis C virus replication in vitro. Hepatology. 2006;43:761–770. doi: 10.1002/hep.21102. [DOI] [PubMed] [Google Scholar]
  • 108.Pasquinelli C. et al. 2009. Safety, tolerability, pharmacokinetics and antiviral activity following single- and multiple-dose administration of BMS-650032, a novel HCV NS3 inhibitor, in subjects with chronic genotype 1HCV infection. 60th annual meeting of the American Association for the Study of Liver Diseases (AASLD), Boston, USA.
  • 109.Pavlovic D., Neville D. C., Argaud O., et al. The hepatitis C virus p7 protein forms an ion channel that is inhibited by long-alkyl-chain iminosugar derivatives. Proc Natl Acad Sci USA. 2003;100:6104–6108. doi: 10.1073/pnas.1031527100. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 110.Perni R. B., Almquist S. J., Byrn R. A., et al. Preclinical profile of VX-950, a potent, selective, and orally bioavailable inhibitor of hepatitis C virus NS3-4A serine protease. Antimicrob.Agents Chemother. 2006;50:899–909. doi: 10.1128/AAC.50.3.899-909.2006. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 111.Pierra C., Amador A., Benzaria S., et al. Synthesis and pharmacokinetics of valopicitabine (NM283), an efficient prodrug of the potent anti-HCV agent 2′-C-methylcytidine. J Med Chem. 2006;49:6614–6620. doi: 10.1021/jm0603623. [DOI] [PubMed] [Google Scholar]
  • 112.Pileri P., Uematsu Y., Campagnoli S., et al. Binding of hepatitis C virus to CD81. Science. 1998;282:938–941. doi: 10.1126/science.282.5390.938. [DOI] [PubMed] [Google Scholar]
  • 113.Ploss A., Evans M. J., Gaysinskaya V. A., et al. Human occludin is a hepatitis C virus entry factor required for infection of mouse cells. Nature. 2009;457:882–886. doi: 10.1038/nature07684. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 114.Pockros P. J., Nelson D., Godofsky E., et al. R1626 plus peginterferon Alfa-2a provides potent suppression of hepatitis C virus RNA and significant antiviral synergy in combination with ribavirin. Hepatology. 2008;48:385–397. doi: 10.1002/hep.22357. [DOI] [PubMed] [Google Scholar]
  • 115.Premkumar A., Wilson L., Ewart G. D., et al. Cation-selective ion channels formed by p7 of hepatitis C virus are blocked by hexamethylene amiloride. FEBS Lett. 2004;557:99–103. doi: 10.1016/S0014-5793(03)01453-4. [DOI] [PubMed] [Google Scholar]
  • 116.Puyang X, Poulin D L, Mathy J E, et al. 2010. Mechanism of Resistance of HCV Replicons to Structurally Distinct Cyclophilin Inhibitors. Antimicrob. Agents Chemother, doi:AAC.01236-09. [DOI] [PMC free article] [PubMed]
  • 117.Randolph J. T., Flentge C. A., Huang P. P., et al. Synthesis and biological characterization of B-ring amino analogues of potent benzothiadiazine hepatitis C virus polymerase inhibitors. J Med Chem. 2009;52:3174–3183. doi: 10.1021/jm801485z. [DOI] [PubMed] [Google Scholar]
  • 118.Reesink H. W., Fanning G. C., Farha K. A., et al. Rapid HCV-RNA decline with once daily TMC435: a phase I study in healthy volunteers and hepatitis C patients. Gastroenterology. 2010;138:913–921. doi: 10.1053/j.gastro.2009.10.033. [DOI] [PubMed] [Google Scholar]
  • 119.Reesink H. W., Zeuzem S., Weegink C. J., et al. Rapid decline of viral RNA in hepatitis C patients treated with VX-950: a phase Ib, placebo-controlled, randomized study. Gastroenterology. 2006;131:997–1002. doi: 10.1053/j.gastro.2006.07.013. [DOI] [PubMed] [Google Scholar]
  • 120.Reiser M., Hinrichsen H., Benhamou Y., et al. Antiviral efficacy of NS3-serine protease inhibitor BILN-2061 in patients with chronic genotype 2 and 3 hepatitis C. Hepatology. 2005;41:832–835. doi: 10.1002/hep.20612. [DOI] [PubMed] [Google Scholar]
  • 121.Roberts C D. 2008. Targeting HCV NS4b Function: A New Approach to Anti-HCV Activity. Inaugural HCV Drug Discovery meeting, San Diego, CA.
  • 122.Roberts S. K., Cooksley G., Dore G. J., et al. Robust antiviral activity of R1626, a novel nucleoside analog: a randomized, placebo-controlled study in patients with chronic hepatitis C. Hepatology. 2008;48:398–406. doi: 10.1002/hep.22321. [DOI] [PubMed] [Google Scholar]
  • 123.Robida J. M., Nelson H. B., Liu Z., et al. Characterization of hepatitis C virus subgenomic replicon resistance to cyclosporine in vitro. J Virol. 2007;81:5829–5840. doi: 10.1128/JVI.02524-06. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 124.Rodriguez-Torres M., Lalezari J., Gane E. J., et al. Potent antiviral response to the HCV nucleoside polymerase inhibitor R7128 for 28 days with peg-IFN and ribavirin: subanalysis by race/ethnicity, weight, and HCV genotype. Hepatology. 2008;48(Suppl.1):1160A. [Google Scholar]
  • 125.Rodriguez-Torres M, Lawitz E, Flach S, et al. 2009. Antiviral activity, pharmacokinetics, safety, and tolerability of PSI-7851, a novel nucleotide polymerase inhibitor for HCV, following single and 3 Day multiple ascending oral doses in healthy volunteers and patients with chronic HCV infection. 60th Annual Meeting of the American Association for the Study of Liver Diseases, Boston, MA.
  • 126.Rodriguez-Torres M, Lawitz E, Conway B, et al. 2010. Safety and antiviral activity of the HCV non-nucleoside polymerase inhibitor VX-222 in treatment-naïve genotype 1 HCV-infected patients. 45thAnnual Meeting of the European Association for the Study of the Liver (EASL) in Vienna, Austria
  • 127.Rossignol J. F., Kabil S. M., El-Gohary Y., et al. Clinical trial: randomized, double-blind, placebo-controlled study of nitazoxanide monotherapy for the treatment of patients with chronic hepatitis C genotype 4. Aliment Pharmacol Ther. 2008;28:574–580. doi: 10.1111/j.1365-2036.2008.03781.x. [DOI] [PubMed] [Google Scholar]
  • 128.Sakai A., Claire M. S., Faulk K., et al. The p7 polypeptide of hepatitis C virus is critical for infectivity and contains functionally important genotype-specific sequences. Proc Natl Acad Sci USA. 2003;100:11646–11651. doi: 10.1073/pnas.1834545100. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 129.Sarrazin C., Rouzier R., Wagner F., et al. SCH 503034, a novel hepatitis C virus protease inhibitor, plus pegylated interferon alpha-2b for genotype 1 nonresponders. Gastroenterology. 2007;132:1270–1278. doi: 10.1053/j.gastro.2007.01.041. [DOI] [PubMed] [Google Scholar]
  • 130.Sarrazin C., Zeuzem S. Resistance to direct antiviral agents in patients with hepatitis C virus infection. Gastroenterology. 2010;138:447–462. doi: 10.1053/j.gastro.2009.11.055. [DOI] [PubMed] [Google Scholar]
  • 131.Scarselli E., Ansuini H., Cerino R., et al. The human scavenger receptor class B type I is a novel candidate receptor for the hepatitis C virus. EMBO J. 2002;21:5017–5025. doi: 10.1093/emboj/cdf529. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 132.Seiwert S. D., Andrews S. W., Jiang Y., et al. Preclinical characteristics of the hepatitis C virus NS3/4A protease inhibitor ITMN-191 (R7227) Antimicrob. Agents Chemother. 2008;52:4432–4441. doi: 10.1128/AAC.00699-08. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 133.Shaw A. N., Tedesco R., Bambal R., et al. Substituted benzothiadizine inhibitors of Hepatitis C virus polymerase. Bioorg Med Chem Lett. 2009;19:4350–4353. doi: 10.1016/j.bmcl.2009.05.091. [DOI] [PubMed] [Google Scholar]
  • 134.Sheaffer A K, Lee M S, Chaniewski S, et al. 2008. Resistance to a novel HCV replication inhibitor maps to amino acid changes within the NS4B Sequence. 15th International Symposium on Hepatitis C and Related Viruses, San Antonio, Texas.
  • 135.Shi S. T., Herlihy K. J., Graham J. P., et al. Preclinical characterization of PF-00868554, a potent nonnucleoside inhibitor of the hepatitis C virus RNA-dependent RNA polymerase. Antimicrob Agents Chemother. 2009;53:2544–2552. doi: 10.1128/AAC.01599-08. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 136.Stankiewicz-Drogon A., Palchykovska L. G., Kostina V. G., et al. New acridone-4-carboxylic acid derivatives as potential inhibitors of hepatitis C virus infection. Bioorg Med Chem. 2008;16:8846–8852. doi: 10.1016/j.bmc.2008.08.074. [DOI] [PubMed] [Google Scholar]
  • 137.Steinkuhler C., Biasiol G., Brunetti M., et al. Product inhibition of the hepatitis C virus NS3 protease. Biochemistry. 1998;37:8899–8905. doi: 10.1021/bi980313v. [DOI] [PubMed] [Google Scholar]
  • 138.Steinmann E., Penin F., Kallis S., et al. Hepatitis C virus p7 protein is crucial for assembly and release of infectious virions. PLoS Pathog. 2007;3:e103. doi: 10.1371/journal.ppat.0030103. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 139.Steinmann E., Whitfield T., Kallis S., et al. Antiviral effects of amantadine and iminosugar derivatives against hepatitis C virus. Hepatology. 2007;46:330–338. doi: 10.1002/hep.21686. [DOI] [PubMed] [Google Scholar]
  • 140.Taliani M., Bianchi E., Narjes F., et al. A continuous assay of hepatitis C virus protease based on resonance energy transfer depsipeptide substrates. Anal Biochem. 1996;240:60–67. doi: 10.1006/abio.1996.0331. [DOI] [PubMed] [Google Scholar]
  • 141.Tellinghuisen T. L., Marcotrigiano J., Rice C. M. Structure of the zinc-binding domain of an essential component of the hepatitis C virus replicase. Nature. 2005;435:374–379. doi: 10.1038/nature03580. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 142.Thibeault D., Maurice R., Pilote L., et al. In vitro characterization of a purified NS2/3 protease variant of hepatitis C virus. J Biol Chem. 2001;276:46678–46684. doi: 10.1074/jbc.M108266200. [DOI] [PubMed] [Google Scholar]
  • 143.Tomei L., Failla C., Santolini E., et al. NS3 is a serine protease required for processing of hepatitis C virus polyprotein. J Virol. 1993;67:4017–4026. doi: 10.1128/jvi.67.7.4017-4026.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 144.Ujjinamatada R. K., Baier A., Borowski P., et al. An analogue of AICAR with dual inhibitory activity against WNV and HCV NTPase/helicase: synthesis and in vitro screening of 4-carbamoyl-5-(4,6-diamino-2, 5-dihydro-1,3,5-triazin-2-yl) imidazole-1-beta-D-ribofura-noside. Bioorg Med Chem Lett. 2007;17:2285–2288. doi: 10.1016/j.bmcl.2007.01.074. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 145.Vaillancourt F. H., Pilote L., Cartier M., et al. Identification of a lipid kinase as a host factor involved in hepatitis C virus RNA replication. Virology. 2009;387:5–10. doi: 10.1016/j.virol.2009.02.039. [DOI] [PubMed] [Google Scholar]
  • 146.Wakita T., Pietschmann T., Kato T., et al. Production of infectious hepatitis C virus in tissue culture from a cloned viral genome. Nat Med. 2005;11:791–796. doi: 10.1038/nm1268. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 147.Watashi K., Hijikata M., Hosaka M., et al. Cyclosporin A suppresses replication of hepatitis C virus genome in cultured hepatocytes. Hepatology. 2003;38:1282–1288. doi: 10.1053/jhep.2003.50449. [DOI] [PubMed] [Google Scholar]
  • 148.Watashi K., Ishii N., Hijikata M., et al. Cyclophilin B is a functional regulator of hepatitis C virus RNA polymerase. Mol Cell. 2005;19:111–122. doi: 10.1016/j.molcel.2005.05.014. [DOI] [PubMed] [Google Scholar]
  • 149.Wedemeyer H., Schuller E., Schlaphoff V., et al. Therapeutic vaccine IC41 as late add-on to standard treatment in patients with chronic hepatitis C. Vaccine. 2009;27:5142–5151. doi: 10.1016/j.vaccine.2009.06.027. [DOI] [PubMed] [Google Scholar]
  • 150.Welbourn S., Green R., Gamache I., et al. Hepatitis C virus NS2/3 processing is required for NS3 stability and viral RNA replication. J Biol Chem. 2005;280:29604–29611. doi: 10.1074/jbc.M505019200. [DOI] [PubMed] [Google Scholar]
  • 151.Whitby K., Taylor D., Patel D., et al. Action of celgosivir (6 O-butanoyl castanospermine) against the pestivirus BVDV: implications for the treatment of hepatitis C. Antivir Chem Chemother. 2004;15:141–151. doi: 10.1177/095632020401500304. [DOI] [PubMed] [Google Scholar]
  • 152.Xiang A. X., Webber S. E., Kerr B. M., et al. Discovery of ANA975: an oral prodrug of the TLR-7 agonist isatoribine. Nucleosides Nucleotides Nucleic Acids. 2007;26:635–640. doi: 10.1080/15257770701490472. [DOI] [PubMed] [Google Scholar]
  • 153.Xue Q., Ding H., Liu M., et al. Inhibition of hepatitis C virus replication and expression by small interfering RNA targeting host cellular genes. Arch Virol. 2007;152:955–962. doi: 10.1007/s00705-006-0905-x. [DOI] [PubMed] [Google Scholar]
  • 154.Yang F., Robotham J. M., Nelson H. B., et al. Cyclophilin A is an essential cofactor for hepatitis C virus infection and the principal mediator of cyclosporine resistance in vitro. J Virol. 2008;82:5269–5278. doi: 10.1128/JVI.02614-07. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 155.Yang W., Zhao Y., Fabrycki J., et al. Selection of replicon variants resistant to ACH-806, a novel hepatitis C virus inhibitor with no cross-resistance to NS3 protease and NS5B polymerase inhibitors. Antimicrob. Agents Chemother. 2008;52:2043–2052. doi: 10.1128/AAC.01548-07. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 156.Yi M., Villanueva R. A., Thomas D. L., et al. Production of infectious genotype 1a hepatitis C virus (Hutchinson strain) in cultured human hepatoma cells. Proc Natl Acad Sci USA. 2006;103:2310–2315. doi: 10.1073/pnas.0510727103. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 157.Yoshida E., Kunimoto D., Lee S. S., et al. Results of a phase 2 dose ranging study of orally administered celgosivir as monotherapy in chronic hepatitis C genotype 1 patients. Gastroenterology. 2006;130:A784. [Google Scholar]
  • 158.Zeuzem S., Yoshida E. M., Benhamou Y., et al. Albinterferon alfa-2b dosed every two or four weeks in interferon-naive patients with genotype 1 chronic hepatitis C. Hepatology. 2008;48:407–417. doi: 10.1002/hep.22403. [DOI] [PubMed] [Google Scholar]
  • 159.Zhong J., Gastaminza P., Cheng G., et al. Robust hepatitis C virus infection in vitro. Proc Natl Acad Sci USA. 2005;102:9294–9299. doi: 10.1073/pnas.0503596102. [DOI] [PMC free article] [PubMed] [Google Scholar]

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