Current and future antiviral therapy of severe seasonal and avian influenza

John Beigel, Mike Bray, John Beigel, Mike Bray

Abstract

The currently circulating H3N2 and H1N1 subtypes of influenza A virus cause a transient, febrile upper respiratory illness in most adults and children ("seasonal influenza"), but infants, the elderly, immunodeficient and chronically ill persons may develop life-threatening primary viral pneumonia or complications such as bacterial pneumonia. By contrast, avian influenza viruses such as the H5N1 virus that recently emerged in Southeast Asia can cause severe disease when transferred from domestic poultry to previously healthy people ("avian influenza"). Most H5N1 patients present with fever, cough and shortness of breath that progress rapidly to adult respiratory distress syndrome. In seasonal influenza, viral replication remains confined to the respiratory tract, but limited studies indicate that H5N1 infections are characterized by systemic viral dissemination, high cytokine levels and multiorgan failure. Gastrointestinal infection and encephalitis also occur. The licensed anti-influenza drugs (the M2 ion channel blockers, amantadine and rimantadine, and the neuraminidase inhibitors, oseltamivir and zanamivir) are beneficial for uncomplicated seasonal influenza, but appropriate dosing regimens for severe seasonal or H5N1 viral infections have not been defined. Treatment options may be limited by the rapid emergence of drug-resistant viruses. Ribavirin has also been used to a limited extent to treat influenza. This article reviews licensed drugs and treatments under development, including high-dose oseltamivir; parenterally administered neuraminidase inhibitors, peramivir and zanamivir; dimeric forms of zanamivir; the RNA polymerase inhibitor T-705; a ribavirin prodrug, viramidine; polyvalent and monoclonal antibodies; and combination therapies.

Figures

Fig. 1
Fig. 1
The influenza A virus replication cycle. The virion core contains eight RNA genome segments encapsidated by nucleoprotein (RNPs) and embedded together with associated polymerase (P) molecules in a matrix of M1 proteins. After binding to sialic acid–galactose linked to a cell-surface glycoprotein or glycolipid, the virion is taken up in an endocytic vesicle, where acidification triggers a conformational change that bring viral and endosomal membranes together. Acidification also produces a flow of protons through the M2 ion channel into the interior of the virion, causing the RNPs to dissociate from the M1 matrix and be released into the cytoplasm. They are then transported to the nucleus, where a viral polymerase complex performs transcription and genome replication. The resulting mRNAs move to the cytoplasm and are translated, producing new RNP protein components that are transported back to the nucleus to associate with nascent genome segments. The exit of new RNPs from the nucleus is aided by the viral NS2 (nuclear export protein, NEP). Meanwhile, nascent HA, NA and M2 molecules pass through the Golgi apparatus and undergo glycosylation before moving to the cell membrane. HA is also cleaved to form two chains linked by a disulfide bond. Virion assembly occurs as RNPs and M1 proteins associate with cytoplasmic tails of HA and NA. Successful release of new virus particles requires that NA cleave sialic acid from galactose on the cell surface or on adjacent virions to prevent HA binding.
Fig. 2
Fig. 2
Licensed antivirals that block the influenza A M2 ion channel: amantadine (A); rimantadine (B) (Courtesy of Pieter Leyssen).
Fig. 3
Fig. 3
The structure of N-acetylneuraminic (sialic) acid (A) and antiviral drugs that compete with it for the active site of the influenza A or B neuraminidase: oseltamivir (B); zanamivir (C); peramivir (D) (Courtesy of Pieter Leyssen).
Fig. 4
Fig. 4
Nucleoside analogues that interfere with influenza virus RNA polymerase function: ribavirin (A); viramidine (B); T-705 (C) (Courtesy of Pieter Leyssen).

References

    1. Apisarnthanarak A., Kitphati R., Thongphubeth K., Patoomanunt P., Anthanont P., Auwanit W., Thawatsupha P., Chittaganpitch M., Saeng-Aroon S., Waicharoen S., Apisarnthanarak P., Storch G.A., Mundy L.M., Fraser V.J. Atypical avian influenza (H5N1) Emerg. Infect. Dis. 2004;10:1321–1324.
    1. Arabi Y., Gommersall C., Ahmed Q., Boynton B., Memish Z. The critically ill avian influenza A (H5N1) patient. Crit. Care Med. 2007;35:1397–1403.
    1. Babu Y.S., Chand P., Bantia S., Kotian P., Dehghani A., El-Kattan Y., Lin T.H., Hutchison T.L., Elliott A.J., Parker C.D., Ananth S.L., Horn L.L., Laver G.W., Montgomery J.A. BCX-1812 (RWJ-270201): discovery of a novel, highly potent, orally active, and selective influenza neuraminidase inhibitor through structure-based drug design. J. Med. Chem. 2000;43:3482–3486.
    1. Bantia S., Arnold C.S., Parker C.D., Upshaw R., Chand P. Anti-influenza virus activity of peramivir in mice with single intramuscular injection. Antivir. Res. 2006;69:39–45.
    1. Beare A.S., Webster R.G. Replication of avian influenza viruses in humans. Arch. Virol. 1991;119:37–42.
    1. Beigel, J., Harman, L.A., Collis, P.J., McCullough, A., Kilpatrick., J.M., Ruff, D., Mead, E., Alexander, W.J., 2007. Pharmacokinetic and safety evaluations of escalating doses of peramivir administered intravenously in healthy volunteers. ICAAC 2007, Poster A-1408.
    1. Beigel J.H., Farrar J., Han A.M., Hayden F.G., Hyer R., de Jong M.D., Lochindarat S., Nguyen T.K., Nguyen T.H., Tran T.H., Nicoll A., Touch S., Yuen K.Y. Avian influenza A (H5N1) infection in humans. N. Engl. J. Med. 2005;353:1374–1385.
    1. Bright R.A., Medina M.J., Xu X., Perez-Oronoz G., Wallis T.R., Davis X.M., Povinelli L., Cox N.J., Klimov A.I. Incidence of adamantane resistance among influenza A (H3N2) viruses isolated worldwide from 1994 to 2005: a cause for concern. Lancet. 2005;366:1175–1181.
    1. Bright R.A., Shay D.K., Shu B., Cox N.J., Klimov A.I. Adamantane resistance among influenza A viruses isolated early during the 2005–2006 influenza season in the United States. JAMA. 2006;295:891–894.
    1. Buchy P., Mardy S., Vong S., Toyoda T., Aubin J.T., Miller M., Touch S., Sovann L., Dufourcq J.B., Richner B., Tu P.V., Tien N.T., Lim W., Peiris J.S., Van der Werf S. Influenza A/H5N1 virus infection in humans in Cambodia. J. Clin. Virol. 2007;39:164–168.
    1. Buranathai C., Amonsin A., Chaisigh A., Theamboonlers A., Pariyothorn N., Poovorawan Y. Surveillance activities and molecular analysis of H5N1 highly pathogenic avian influenza viruses from Thailand, 2004–2005. Avian Dis. 2007;51:194–200.
    1. Butt K.M., Smith G.J., Chen H., Zhang L.J., Leung Y.H., Xu K.M., Lim W., Webster R.G., Yuen K.Y., Peiris J.S., Guan Y. Human infection with an avian H9N2 influenza A virus in Hong Kong in 2003. J. Clin. Microbiol. 2005;43:5760–5767.
    1. Calfee D.P., Peng A.W., Cass L.M., Lobo M., Hayden F.G. Safety and efficacy of intravenous zanamivir in preventing experimental human influenza A virus infection. Antimicrob. Agents Chemother. 1999;43:1616–1620.
    1. Carr J., Ives J., Kelly L., Lambkin R., Oxford J., Mendel D., Tai L., Roberts N. Influenza virus carrying neuraminidase with reduced sensitivity to oseltamivir carboxylate has altered properties in vitro and is compromised for infectivity and replicative ability in vivo. Antivir. Res. 2002;54:79–88.
    1. Carter M.J. A rationale for using steroids in the treatment of severe cases of H5N1 avian influenza. J. Med. Microbiol. 2007;56:875–883.
    1. Chan P.K. Outbreak of avian influenza A(H5N1) virus infection in Hong Kong in 1997. Clin. Infect. Dis. 2002;34(Suppl 2):S58–S64.
    1. Chan M.C., Cheung C.Y., Chui W.H., Tsao S.W., Nicholls J.M., Chan Y.O., Chan R.W., Long H.T., Poon L.L., Guan Y., Peiris J.S. Proinflammatory cytokine responses induced by influenza A (H5N1) viruses in primary human alveolar and bronchial epithelial cells. Respir. Res. 2005;6:135.
    1. Chand P., Bantia S., Kotian P.L., El-Kattan Y., Lin T.H., Babu Y.S. Comparison of the anti-influenza virus activity of cyclopentane derivatives with oseltamivir and zanamivir in vivo. Bioorg. Med. Chem. 2005;13:4071–4077.
    1. Cheung C.L., Rayner J.M., Smith G.J., Wang P., Naipospos T.S., Zhang J., Yuen K.Y., Webster R.G., Peiris J.S., Guan Y., Chen H. Distribution of amantadine-resistant H5N1 avian influenza variants in Asia. J. Infect. Dis. 2006;193:1626–1629.
    1. Cheung C.Y., Poon L.L., Lau A.S., Luk W., Lau Y.L., Shortridge K.F., Gordon S., Guan Y., Peiris J.S. Induction of proinflammatory cytokines in human macrophages by influenza A (H5N1) viruses: a mechanism for the unusual severity of human disease? Lancet. 2002;360:1831–1837.
    1. Conenello G., Zamarin D., Perrone L., Palese P. A single mutation in the PB1-F2 of H5N1 (HK/97) and 1918 influenza A viruses contributes to increased virulence. PloS Pathogens. 2007;3:e141.
    1. Cooper N.J., Sutton A.J., Abrams K.R., Wailoo A., Turner D., Nicholson K.G. Effectiveness of neuraminidase inhibitors in treatment and prevention of influenza A and B: systematic review and meta-analyses of randomised controlled trials. BMJ. 2003;326:1235–1242.
    1. Cyranoski D. China's chicken farmers under fire for antiviral abuse. Nature. 2005;435:1009.
    1. De Clercq E. Antiviral agents active against influenza A viruses. Nat. Rev. Drug Discov. 2006;5:1015–1025.
    1. De Jong M.D., Bach V.C., Phan T.Q., Vo M.H., Tran T.T., Nguyen B.H., Beld M., Le T.P., Truong H.K., Nguyen V.V., Tran T.H., Do Q.H., Farrar J. Fatal avian influenza A (H5N1) in a child presenting with diarrhea followed by coma. N. Engl. J. Med. 2005;352:686–691.
    1. De Jong M.D., Simmons C.P., Thanh T.T., Hien V.M., Smith G.J., Chau T.N., Hoang D.M., Chau N.V., Khanh T.H., Dong V.C., Qui P.T., Cam B.V., Ha do Q., Guan Y., Peiris J.S., Chinh N.T., Hien T.T., Farrar J. Fatal outcome of human influenza A (H5N1) is associated with high viral load and hypercytokinemia. Nat. Med. 2006;12:1203–1207.
    1. De Jong M.D., Tran T.T., Truong H.K., Vo M.H., Smith G.J., Nguyen V.C., Bach V.C., Phan T.Q., Do Q.H., Guan Y., Peiris J.S., Tran T.H., Farrar J. Oseltamivir resistance during treatment of influenza A (H5N1) infection. N. Engl. J. Med. 2005;353:2667–2672.
    1. Dybing J.K., Schultz-Cherry S., Swayne D.E., Suarez D.L., Perdue M.L. Distinct pathogenesis of Hong Kong-origin H5N1 viruses in mice compared to that of other highly pathogenic H5 avian influenza viruses. J. Virol. 2000;74:1443–1450.
    1. Furuta Y., Takahashi K., Fukuda Y., Kuno M., Kamiyama T., Kozaki K., Nomura N., Egawa H., Minami S., Watanabe Y., Narita H., Shiraki K. In vitro and in vivo activities of anti-influenza virus compound T-705. Antimicrob. Agents Chemother. 2002;46:977–981.
    1. Fouchier R.A., Schneeberger P.M., Rozendaal F.W., Broekman J.M., Kemink S.A., Munster V., Kuiken T., Rimmelzwaan G.F., Schutten M., Van Doornum G.J., Koch G., Bosman A., Koopmans M., Osterhaus A.D. Avian influenza A virus (H7N7) associated with human conjunctivitis and a fatal case of acute respiratory distress syndrome. Proc. Natl. Acad. Sci. U.S.A. 2004;101:1356–1361.
    1. Furuta Y., Takahashi K., Kuno-Maekawa M., Sangawa H., Uehara S., Kozaki K., Nomura N., Egawa H., Shiraki K. Mechanism of action of T-705 against influenza virus. Antimicrob. Agents Chemother. 2005;49:981–986.
    1. Garcia-Sastre A. Antiviral response in pandemic influenza viruses. Emerg. Infect. Dis. 2006;12:44–47.
    1. Ge Q., Filip L., Bai A., Nguyen T., Eisen H.N., Chen J. Inhibition of influenza virus production in virus-infected mice by RNA interference. Proc. Natl. Acad Sci. U.S.A. 2004;101(23):8676–8681.
    1. Ge Q., Pastey M., Kobasa D., Puthavathana P., Lupfer C., Bestwick R.K., Iversen P.L., Chen J., Stein D.A. Inhibition of multiple subtypes of influenza A virus in cell cultures with morpholino oligomers. Antimicrob. Agents Chemother. 2006;50(11):3724–3733.
    1. Gillim-Ross L., Subbarao K. Can immunity induced by the human influenza virus N1 neuraminidase provide some protection from avian influenza H5N1 viruses? PLoS Med. 2007;4:e91.
    1. Gish R. Treating HCV with ribavirin analogues and ribavirin-like molecules. J. Antimicrob. Chemother. 2006;57:8–13.
    1. Glaser L., Conenello G., Paulson J., Palese P. Effective replication of human influenza viruses in mice lacking a major α2,6 sialyltransferase. Virus Res. 2007;126:9–18.
    1. Govorkova E.A., Fang H.B., Tan M., Webster R.G. Neuraminidase inhibitor-rimantadine combinations exert additive and synergistic anti-influenza virus effects in MDCK cells. Antimicrob. Agents Chemother. 2004;48:4855–4856.
    1. Govorkova E.A., Ilyushina N.A., Boltz D.A., Douglas A., Yilmaz N., Webster R.G. Efficacy of oseltamivir therapy in ferrets inoculated with different clades of H5N1 influenza virus. Antimicrob. Agents Chemother. 2007;51:1414–1424.
    1. Govorkova E.A., Leneva I.A., Goloubeva O.G., Bush K., Webster R.G. Comparison of efficacies of RWJ-270201, zanamivir, and oseltamivir against H5N1, H9N2, and other avian influenza viruses. Antimicrob. Agents Chemother. 2001;45:2723–2732.
    1. Gowen B.B., Wong M.H., Jung K.H., Sanders A.B., Mendenhall M., Bailey K.W., Furuta Y., Sidwell R.W. In vitro and in vivo activities of T-705 against arenavirus and bunyavirus infections. Antimicrob. Agents Chemother. 2007;51:3168–3176.
    1. Gubareva L.V., Webster R.G., Hayden F.G. Comparison of the activities of zanamivir, oseltamivir, and RWJ-270201 against clinical isolates of influenza virus and neuraminidase inhibitor-resistant variants. Antimicrob. Agents Chemother. 2001;45:3403–3408.
    1. Hanson B.J., Boon A.C.M., Lim A.P.C., Webb A., Ooi E.E., Webby R.J. Passive immunoprophylaxis and therapy with humanized monoclonal antibody specific for influenza A H5 hemagglutinin in mice. Respir. Res. 2006;7:126.
    1. Hayden F.G. Antiviral resistance in influenza viruses—implications for management and pandemic response. N. Engl. J. Med. 2006;354:785–788.
    1. Hayden F.G., Osterhaus A.D., Treanor J.J., Fleming D.M., Aoki F.Y., Nicholson K.G., Bohnen A.M., Hirst H.M., Keene O., Wightman K. Efficacy and safety of the neuraminidase inhibitor zanamivir in the treatment of influenza virus infections. GG167 Influenza Study Group. N. Engl. J. Med. 1997;337:874–880.
    1. Hayden F.G., Palese P. Influenza virus. In: Richman D., Whitley R., Hayden F., editors. Clinical Virology. 2nd ed. ASM Press; Washington, DC: 2002. pp. 891–920.
    1. Hayden F.G., Sable C.A., Connor J.D., Lane J. Intravenous ribavirin by constant infusion for serious influenza and parainfluenza virus infection. Antivir. Ther. 1996;1:51–56.
    1. He G., Qiao J., Dong C., He C., Zhao L., Tian Y. Amantadine resistance among H5N1 avian influenza viruses isolated in Northern China. Antivir. Res. 2008;77:72–76.
    1. Herlocher M.L., Carr J., Ives J., Elias S., Truscon R., Roberts N., Monto A.S. Influenza virus carrying an R292K mutation in the neuraminidase gene is not transmitted in ferrets. Antivir. Res. 2002;54:99–111.
    1. Herlocher M.L., Truscon R., Elias S., Yen H.L., Roberts N.A., Ohmit S.E., Monto A.S. Influenza viruses resistant to the antiviral drug oseltamivir: transmission studies in ferrets. J. Infect. Dis. 2004;190:1627–1630.
    1. Honda T., Masuda T., Yoshida S., Arai M., Kaneko S., Yamashita M. Synthesis and anti-influenza virus activity of 7-O-alkylated derivatives related to zanamivir. Bioorg. Med. Chem. Lett. 2002;12:1925–1928.
    1. Ibricevic A., Pekosz A., Walter M.J., Newby C., Battaile J.T., Brown E.G., Holtzman M.J., Brody S.L. Influenza virus receptor specificity and cell tropism in mouse and human airway epithelial cells. J. Virol. 2006;80:7469–7480.
    1. Ilyushina N.A., Bovin N.V., Webster R.G., Govorkova E.A. Combination chemotherapy, a potential strategy for reducing the emergence of drug-resistant variants. Antivir. Res. 2006;70:121–131.
    1. Ilyushina N.A., Hoffmann E., Solomon R., Webster R.G., Govorkova E.A. Amantadine-oseltamivir combination therapy for H5N1 influenza virus infection in mice. Antivir. Ther. 2007;12:363–370.
    1. Ison M.G., Gnann J.W., Jr., Nagy-Agren S., Treannor J., Paya C., Steigbigel R., Elliott M., Weiss H.L., Hayden F.G. Safety and efficacy of nebulized zanamivir in hospitalized patients with serious influenza. Antivir. Ther. 2003;8:183–190.
    1. Ison M.G., Gubarova L.V., Atmar R.L., Treanor J., Hayden F.G. Recovery of drug-resistant influenza virus from immunocompromised patients: a case series. J. Infect. Dis. 2006;193:760–764.
    1. Jefferson T., Demicheli V., Rivetti D., Jones M., Di Pietrantonj C., Rivetti A. Antivirals for influenza in healthy adults: systematic review. Lancet. 2006;367:303–313.
    1. Kaiser L., Wat C., Mills T., Mahoney P., Ward P., Hayden F. Impact of oseltamivir treatment on influenza-related lower respiratory tract complications and hospitalizations. Arch. Intern. Med. 2003;163:1667–1672.
    1. Kiso M., Mitamura K., Sakai-Tagawa Y., Shiraishi K., Kawakami C., Kimura K., Hayden F.G., Sugaya N., Kawaoka Y. Resistant influenza A viruses in children treated with oseltamivir: descriptive study. Lancet. 2004;364:759–765.
    1. Knight V., Gilbert B.E. Ribavirin aerosol treatment of influenza. Infect. Dis. Clin. North Am. 1987;1:441–457.
    1. Koopmans M., Wilbrink B., Conyn M., Natrop G., van der Nat H., Vennema H., Meijer A., van Steenbergen J., Fouchier R., Osterhaus A., Bosman A. Transmission of H7N7 avian influenza A virus to human beings during a large outbreak in commercial poultry farms in the Netherlands. Lancet. 2004;363:587–593.
    1. Le Q.M., Kiso M., Someya K., Sakai Y.T., Nguyen T.H., Nguyen K.H., Pham N.D., Nguyen H.H., Yamada S., Muramoto Y., Horimoto T., Takada A., Goto H., Suzuki T., Suzuki Y., Kawaoka Y. Avian flu: isolation of drug-resistant H5N1 virus. Nature. 2005;437:1108.
    1. Leekha S., Zitterkopf N.L., Espy M.J., Smith T.F., Thompson R.L., Sampathkumar P. Duration of influenza A virus shedding in hospitalized patients and implications for infection control. Infect. Control Hosp. Epidemiol. 2007;28:1071–1076.
    1. Leyssen P., De Clercq E., Neyts J. Molecular strategies to inhibit the replication of RNA viruses. Antivir. Res. 2008;78:9–25.
    1. Li K.S., Guan Y., Wang J., Smith G.J., Xu K.M., Duan L., Rahardjo A.P., Puthavathana P., Buranathai C., Nguyen T.D., Estoepangestie A.T., Chaisingh A., Auewarakul P., Long H.T., Hanh N.T., Webby R.J., Poon L.L., Chen H., Shortridge K.F., Yuen K.Y., Webster R.G., Peiris J.S. Genesis of a highly pathogenic and potentially pandemic H5N1 influenza virus in eastern Asia. Nature. 2004;430:209–213.
    1. Lu J., Guo Z., Pan X., Wang G., Zhang D., Li Y., Tan B., Ouyang L., Yu X., Lu J. Passive immunotherapy for influenza A H5N1 virus infection with equine hyperimmune globulin F(ab′)2 in mice. Respir. Res. 2006;7:43.
    1. Luke T.C., Kilbane E.M., Jackson J.L., Hoffman S.L. Meta-analysis: convalescent blood products for Spanish influenza pneumonia: a future H5N1 treatment? Ann. Intern. Med. 2006;145:599–609.
    1. Ma W., Vincent A., Gramer M., Brockwell C., Lager K., Janke B., Gauger P., Patnayak D., Webby R., Richt J. Identification of H2N3 influenza A viruses from swine in the United States. Proc. Natl. Acad. Sci. U.S.A. 2008;104:20949–20954.
    1. Macdonald S.J., Cameron R., Demaine D.A., Fenton R.J., Foster G., Gower D., Hamblin J.N., Hamilton S., Hart G.J., Hill A.P., Inglis G.G., Jin B., Jones H.T., McConnell D.B., McKimm-Breschkin J., Mills G., Nguyen V., Owens I.J., Parry N., Shanahan S.E., Smith D., Watson K.G., Wu W.Y., Tucker S.P. Dimeric zanamivir conjugates with various linking groups are potent, long-lasting inhibitors of influenza neuraminidase including H5N1 avian influenza. J. Med. Chem. 2005;48:2964–2971.
    1. Macdonald S.J., Watson K.G., Cameron R., Chalmers D.K., Demaine D.A., Fenton R.J., Gower D., Hamblin J.N., Hamilton S., Hart G.J., Inglis G.G., Jin B., Jones H.T., McConnell D.B., Mason A.M., Nguyen V., Owens I.J., Parry N., Reece P.A., Shanahan S.E., Smith D., Wu W.Y., Tucker S.P. Potent and long-acting dimeric inhibitors of influenza virus neuraminidase are effective at a once-weekly dosing regimen. Antimicrob. Agents Chemother. 2004;48:4542–4549.
    1. Maines T.R., Lu X.H., Erb S.M., Edwards L., Guarner J., Greer P.W., Nguyen D.C., Szretter K.J., Chen L.M., Thawatsupha P., Chittaganpitch M., Waicharoen S., Nguyen D.T., Nguyen T., Nguyen H.H., Kim J.H., Hoang L.T., Kang C., Phuong L.S., Lim W., Zaki S., Donis R.O., Cox N.J., Katz J.M., Tumpey T.M. Avian influenza (H5N1) viruses isolated from humans in Asia in 2004 exhibit increased virulence in mammals. J. Virol. 2005;79:11788–11800.
    1. Malakhov M.P., Aschenbrenner L.M., Smee D.F., Wandersee M.K., Sidwell R.W., Gubareva L.V., Mishin V.P., Hayden F.G., Kim D.H., Ing A., Campbell E.R., Yu M., Fang F. Sialidase fusion protein as a novel broad-spectrum inhibitor of influenza virus infection. Antimicrob. Agents Chemother. 2006;50:1470–1479.
    1. Masuda T., Shibuya S., Arai M., Yoshida S., Tomozawa T., Ohno A., Yamashita M., Honda T. Synthesis and anti-influenza evaluation of orally active bicyclic ether derivatives related to zanamivir. Bioorg. Med. Chem. Lett. 2003;13:669–673.
    1. Matrosovich M.N., Matrosovich T.Y., Gray T., Roberts N.A., Klenk H.D. Neuraminidase is important for the initiation of influenza virus infection in human airway epithelium. J. Virol. 2004;78:12665–12667.
    1. McGeer A., Green K., Plevneshi A., Shigayeva A., Siddiqi N., Raboud J., Low D.E. Antiviral therapy and outcomes of influenza requiring hospitalization in Ontario, Canada. Clin. Infect. Dis. 2007;45
    1. Medeiros R., Rameix-Welti M.A., Lorin V., Ribaud P., Manuguerra J.C., Socie G., Scieux C., Naffakh N., van der Werf S. Failure of zanamivir therapy for pneumonia in a bone-marrow transplant recipient infected by a zanamivir-sensitive influenza A (H1N1) virus. Antivir. Ther. 2007;12:571–576.
    1. Monto A.S. Vaccines and antiviral drugs in pandemic preparedness. Emerg. Infect. Dis. 2006;12:55–60.
    1. Moscona A. Neuraminidase inhibitors for influenza. N. Engl. J. Med. 2005;353:1363–1373.
    1. Moscona A. Oseltamivir resistance—disabling our influenza defenses. N. Engl. J. Med. 2005;353:2633–2636.
    1. Moscona A. Medical management of influenza infection. Annu. Rev. Med. 2008;59:397–413.
    1. Mozdzanowska K., Feng J., Gerhard W. Virus-neutralizing activity mediated by the Fab fragment of a hemagglutinin-specific antibody is sufficient for the resolution of influenza virus infection in SCID mice. J. Virol. 2003;77:8322–8328.
    1. Ng W.F., To K.F., Lam W.W., Ng T.K., Lee K.C. The comparative pathology of severe acute respiratory syndrome and avian influenza A subtype H5N1—a review. Hum. Pathol. 2006;37:381–390.
    1. Nicholls J.M., Chan M.C., Chan W.Y., Wong H.K., Cheung C.Y., Kwong D.L., Wong M.P., Chui W.H., Poon L.L., Tsao S.W., Guan Y., Peiris J.S. Tropism of avian influenza A (H5N1) in the upper and lower respiratory tract. Nat. Med. 2007;13:147–149.
    1. Nicholson K.G., Aoki F.Y., Osterhaus A.D., Trottier S., Carewicz O., Mercier C.H., Rode A., Kinnersley N., Ward P. Efficacy and safety of oseltamivir in treatment of acute influenza: a randomised controlled trial. Neuraminidase Inhibitor Flu Treatment Investigator Group. Lancet. 2000;355:1845–1850.
    1. O’Keefe B., Smee D., Turpin J., Saucedo C., Gustafson K., Mori T., Blakeslee D., Buckheit R., Boyd M. Potent anti-influenza activity of cyanovirin-N and interactions with viral hemagglutinin. Antimicrob. Agents Chemother. 2003;47:2518–2525.
    1. Okuno Y., Matsumoto K., Isegawa Y., Ueda S. Protection against the mouse-adapted A/FM/1/47 strain of influenza A virus in mice by a monoclonal antibody with cross-neutralizing activity among H1 and H2 strains. J. Virol. 1994;68:517–520.
    1. Oner A.F., Bay A., Arslan S., Akdeniz H., Sahin H.A., Cesur Y., Epcacan S., Yilmaz N., Deger I., Kizilyildiz B., Karsen H., Ceyhan M. Avian influenza A (H5N1) infection in eastern Turkey in 2006. N. Engl. J. Med. 2006;355:2179–2185.
    1. Osterholm M.T. Preparing for the next pandemic. N. Engl. J. Med. 2005;352:1839–1842.
    1. Palladino G., Mozdzanowska K., Washko G., Gerhard W. Virus-neutralizing antibodies of immunoglobulin G (IgG) but not of IgM or IgA isotypes can cure influenza virus pneumonia in SCID mice. J. Virol. 1995;69:2075–2081.
    1. Peiris M., Yuen K.Y., Leung C.W., Chan K.H., Ip P.L., Lai R.W., Orr W.K., Shortridge K.F. Human infection with influenza H9N2. Lancet. 1999;354:916–917.
    1. Ramisse F., Deramoudt F.X., Szatanik M., Bianchi A., Binder P., Hannoun C., Alonso J.M. Effective prophylaxis of influenza A virus pneumonia in mice by topical passive immunotherapy with polyvalent human immunoglobulins or F(ab′)2 fragments. Clin. Exp. Immunol. 1998;111:583–587.
    1. Rodriguez W.J., Hall C.B., Welliver R., Simoes E.A., Ryan M.E., Stutman H., Johnson G., Van Dyke R., Groothuis J.R., Arrobio J. Efficacy and safety of aerosolized ribavirin in young children hospitalized with influenza: a double-blind, multicenter, placebo-controlled trial. J. Pediatr. 1994;125:129–135.
    1. Russell R.J., Haire L.F., Stevens D.J., Collins P.J., Lin Y.P., Blackburn G.M., Hay A.J., Gamblin A.J., Skehel J.J. The structure of H5N1 avian influenza neuraminidase suggests new opportunities for drug design. Nature. 2006;443:45–49.
    1. Salomon R., Franks J., Govorkova E.A., Ilyushina N.A., Yen H.L., Hulse-Post D.J., Humberd J., Trichet M., Rehg J.E., Webby R.J., Webster R.G., Hoffmann E. The polymerase complex genes contribute to the high virulence of the human H5N1 influenza virus isolate A/Vietnam/1203/04. J. Exp. Med. 2006;203:689–697.
    1. Salomon R., Hoffmann E., Webster R.G. Inhibition of the cytokine response does not protect against lethal H5N1 influenza infection. Proc. Natl. Acad. Sci. U.S.A. 2007;104:12479–12481.
    1. Sandbulte M.R., Jimenez G.S., Boon A.C., Smith L.R., Treanor J.J., Webby R.J. Cross-reactive neuraminidase antibodies afford partial protection against H5N1 in mice and are present in unexposed humans. PLoS Med. 2007;4:e59.
    1. Sato M., Hosoya M., Kato K., Suzuki H. Viral shedding in children with influenza virus infections treated with neuraminidase inhibitors. Pediatr. Infect. Dis. J. 2005;24:931–932.
    1. Schunemann H.J., Hill S.R., Kakad M., Bellamy R., Uyeki T.M., Hayden F.G., Yazdanpanah Y., Beigel J., Chotpitayasunondh T., Del Mar C., Farrar J., Tran T.H., Ozbay B., Sugaya N., Fukuda K., Shindo N., Stockman L., Vist G.E., Croisier A., Nagjdaliyev A., Roth C., Thomson G., Zucker H., Oxman A.D. WHO Rapid Advice Guidelines for pharmacological management of sporadic human infection with avian influenza A (H5N1) virus. Lancet Infect. Dis. 2007;7:21–31.
    1. Seo S.H., Hoffmann E., Webster R.G. Lethal H5N1 influenza viruses escape host anti-viral cytokine responses. Nat. Med. 2002;8:950–954.
    1. Shah R.C. Shift shown in influenza A adamantane resistance. JAMA. 2006;296:1585–1586.
    1. Shinya K., Ebina M., Yamada S., Ono M., Kasai N., Kawaoka Y. Avian flu: influenza virus receptors in the human airway. Nature. 2006;440:435–436.
    1. Shinya K., Hatta M., Yamada S., Takada A., Watanabe S., Halfmann P., Horimoto T., Neumann G., Kim J.H., Lim W., Guan Y., Peiris M., Kiso M., Suzuki T., Suzuki Y., Kawaoka Y. Characterization of a human H5N1 influenza A virus isolated in 2003. J. Virol. 2005;79:9926–9932.
    1. Sidwell R.W., Bailey K.W., Wong M.H., Barnard D.L., Smee D.F. In vitro and in vivo influenza virus-inhibitory effects of viramidine. Antivir. Res. 2005;68:10–17.
    1. Sidwell R.W., Barnard D.L., Day C.W., Smee D.F., Bailey K.W., Wong M.H., Morrey J.D., Furuta Y. Efficacy of orally administered T-705 on lethal avian influenza A (H5N1) virus infections in mice. Antimicrob. Agents Chemother. 2007;51:845–851.
    1. Simmons C.P., Bernasconi N.L., Suguitan A.L., Mills K., Ward J.M., Chau N.V., Hien T.T., Sallusto F., Ha do Q., Farrar J., de Jong M.D., Lanzavecchia A., Subbarao K. Prophylactic and therapeutic efficacy of human monoclonal antibodies against H5N1 influenza. PLoS Med. 2007;4:e178.
    1. Smith C.B., Charette R.P., Fox J.P., Cooney M.K., Hall C.E. Lack of effect of oral ribavirin in naturally occurring influenza A virus infection. J. Infect. Dis. 1980;141:548–554.
    1. Stein D.S., Creticos C.M., Jackson G.G., Bernstein J.M., Hayden F.G., Schiff G.M., Bernstein D.I. Oral ribavirin treatment of influenza A and B. Antimicrob. Agents Chemother. 1987;31:1285–1287.
    1. Stray S.J., Cummings R.D., Air G.M. Influenza virus infection of desialylated cells. Glycobiology. 2000;10:649–658.
    1. Sweet C., Jakeman K.J., Bush K., Wagaman P.C., McKown L.A., Streeter A.J., Desai-Krieger D., Chand P., Babu Y.S. Oral administration of cyclopentane neuraminidase inhibitors protects ferrets against influenza virus infection. Antimicrob. Agents Chemother. 2002;46:996–1004.
    1. Szretter K.J., Gangappa S., Lu X., Smith C., Shieh W.J., Zaki S.R., Sambhara S., Tumpey T.M., Katz J.M. Role of host cytokine responses in the pathogenesis of avian H5N1 influenza viruses in mice. J. Virol. 2007;81:2736–2744.
    1. Takahashi K., Furuta Y., Fukuda Y., Kuno M., Kamiyama T., Kozaki K., Nomura N., Egawa H., Minami S., Shiraki K. In vitro and in vivo activities of T-705 and oseltamivir against influenza virus. Antivir. Chem. Chemother. 2003;14:235–241.
    1. To K.F., Chan P.K., Chan K.F., Lee W.K., Lam W.Y., Wong K.F., Tang N.L., Tsang D.N., Sung R.Y., Buckley T.A., Tam J.S., Cheng A.F. Pathology of fatal human infection associated with avian influenza A H5N1 virus. J. Med. Virol. 2001;63:242–246.
    1. Tompkins S.M., Lo C.Y., Tumpey T.M., Epstein S.L. Protection against lethal influenza virus challenge by RNA interference in vivo. Proc. Natl. Acad. Sci. U.S.A. 2004;101(23):8682–8686.
    1. Treanor J.J., Hayden F.G., Vrooman P.S., Barbarash R., Bettis R., Riff D., Singh S., Kinnersley N., Ward P., Mills R.G. Efficacy and safety of the oral neuraminidase inhibitor oseltamivir in treating acute influenza: a randomized controlled trial. US Oral Neuraminidase Study Group. JAMA. 2000;283:1016–1024.
    1. Tsiodras S., Mooney J.D., Hatzakis A. Role of combination antiviral therapy in pandemic influenza. BMJ. 2007;334:293–294.
    1. Tweed S.A., Skowronski D.M., David S.T., Larder A., Petric M., Lees W., Li Y., Katz J., Krajden M., Tellier R., Halpert C., Hirst M., Astell C., Lawrence D., Mak A. Human illness from avian influenza H7N3, British Columbia. Emerg. Infect. Dis. 2004;10:2196–2199.
    1. Uiprasertkul M., Puthavathana P., Sangsiriwut K., Pooruk P., Srisook K., Peiris M., Nicholls J.M., Chokephaibulkit K., Vanprapar N., Auewarakul P. Influenza A H5N1 replication sites in humans. Emerg. Infect. Dis. 2005;11:1036–1041.
    1. van Riel D., Munster V.J., de Wit E., Rimmelzwaan G.F., Fouchier R.A., Osterhaus A.D., Kuiken T. H5N1 virus attachment to lower respiratory tract. Science. 2006;312:399.
    1. Wagner R., Matrosovich M., Klenk H.D. Functional balance between haemagglutinin and neuraminidase in influenza virus infections. Rev. Med. Virol. 2002;12:159–166.
    1. World Health Organization, 2006. Advice on use of oseltamivir.
    1. World Health Organization, 2007. Cumulative number of confirmed human cases of avian influenza A/(H5N1) reported to WHO, vol. 2007, no. August 15.
    1. Wright P.F., Webster R.G. Orthomyxoviruses. In: Knipe D.M., Howley P.M., editors. Fields Virology. fourth ed. Lippincott Williams & Wilkins; Philadelphia: 2001. pp. 1533–1579.
    1. Wu Y., Zhang G., Li Y., Jin Y., Dale R., Sun L.Q., Wang M. Inhibition of highly pathogenic avian H5N1 influenza virus replication by RNA oligonucleotides targeting NS1 gene. Biochem. Biophys. Res. Commun. 2008;365(2):369–374.
    1. Yen H.L., Herlocher L.M., Hoffmann E., Matrosovich M.N., Monto A.S., Webster R.G., Govorkova E.A. Neuraminidase inhibitor-resistant influenza viruses may differ substantially in fitness and transmissibility. Antimicrob. Agents Chemother. 2005;49:4075–4084.
    1. Yen H.L., Hoffmann E., Taylor G., Scholtissek C., Monto A.S., Webster R.G., Govorkova E.A. Importance of neuraminidase active-site residues to the neuraminidase inhibitor resistance of influenza viruses. J. Virol. 2006;80:8787–8795.
    1. Yen H.L., Ilyushina N.A., Salomon R., Hoffmann E., Webster R.G., Govorkova E.A. Neuraminidase inhibitor-resistant recombinant A/Vietnam/1203/04 (H5N1) influenza viruses retain their replication efficiency and pathogenicity in vitro and in vivo. J. Virol. 2007;81:12418–12426.
    1. Yen H.L., Monto A.S., Webster R.G., Govorkova E.A. Virulence may determine the necessary duration and dosage of oseltamivir treatment for highly pathogenic A/Vietnam/1203/04 influenza virus in mice. J. Infect. Dis. 2005;192:665–672.
    1. Yuen K.Y., Chan P.K., Peiris M., Tsang D.N., Que T.L., Shortridge K.F., Cheung P.T., To W.K., Ho E.T., Sung R., Cheng A.F. Clinical features and rapid viral diagnosis of human disease associated with avian influenza A H5N1 virus. Lancet. 1998;351:467–471.
    1. Zhou B., Zhong N., Guan Y. Treatment with convalescent plasma for influenza A (H5N1) infection. N. Engl. J. Med. 2007;357:1450–1451.
    1. Zhou H., Jin M., Yu Z., Xu X., Peng Y., Wu H., Liu J., Liu H., Cao S., Chen H. Effective small interfering RNAs targeting matrix and nucleocapsid protein gene inhibit influenza A virus replication in cells and mice. Antivir. Res. 2007;76(2):186–193.
    1. Zürcher T., Yates P.J., Daly J., Sahasrabudhe A., Walters M., Dash L., Tisdale M., McKimm-Breschkin J.L. Mutations conferring zanamivir resistance in human influenza virus N2 neuraminidases compromise virus fitness and are not stably maintained in vitro. J. Antimicrob. Chemother. 2006;58:723–732.

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