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Gillespie SW, Reddy AS, Burris DM, Naqvi SH, Byrareddy SN, Lorson CL, Singh K. Islatravir: evaluation of clinical development for HIV and HBV. Expert Opin Investig Drugs 2024; 33:85-93. [PMID: 38235744 DOI: 10.1080/13543784.2024.2305130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Accepted: 01/10/2024] [Indexed: 01/19/2024]
Abstract
INTRODUCTION Islatravir (ISL) is a nucleoside reverse transcriptase translocation inhibitor (NRTTI) that inhibits HIV RT through multiple mechanisms. Contrary to all approved NtRTIs, islatravir retains a 3'OH group. In vitro and clinical data show that ISL is an ultrapotent investigational drug with high tolerability. AREAS COVERED The historical development of islatravir and its mechanisms of HIV and HBV inhibition and resistance are covered. Additionally, the outcomes of Phase I and Phase II clinical trials are discussed. EXPERT OPINION Current first-line antiretroviral therapy, preexposure, and postexposure prophylactic interventions are highly effective in maintaining low or undetectable viral load. Despite these measures, an unusually high rate of new infections every year warrants developing novel antivirals that can suppress drug-resistant HIV and improve compliance. ISL, an NRTTI once deemed a long-acting drug, was placed on a clinical hold. The outcome of ongoing clinical trials with a reduced ISL dose will decide its future clinical application. Additionally, MK-8527, which inhibits HIV via same mechanism as that of ISL may supersede ISL. Data on ISL inhibition of HBV are scarce, and preclinical data show dramatically lower ISL efficacy against HBV than currently preferred nucleos(t)ide drugs, indicating that ISL may not be a potent anti-HBV drug.
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Affiliation(s)
| | - Athreya S Reddy
- Bond Life Sciences Center, University of Missouri, Columbia, MO, USA
| | - Dana M Burris
- Bond Life Sciences Center, University of Missouri, Columbia, MO, USA
| | - S Hasan Naqvi
- Department of Medicine, University of Missouri, Columbia, MO, USA
| | - Siddappa N Byrareddy
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE, USA
| | - Christian L Lorson
- Bond Life Sciences Center, University of Missouri, Columbia, MO, USA
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO, USA
| | - Kamal Singh
- Bond Life Sciences Center, University of Missouri, Columbia, MO, USA
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO, USA
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2
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Tu T, Ajoyan H, George J. Novel Assays to Solve the Clinical and Scientific Challenges of Chronic Hepatitis B. Clin Liver Dis 2023; 27:837-855. [PMID: 37778773 DOI: 10.1016/j.cld.2023.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/03/2023]
Abstract
Chronic infection with Hepatitis B is a common, incurable, and deadly infection. Despite inexpensive laboratory tests for diagnosis and management that have been established for decades, the worldwide rate of diagnosis is only ∼10%, and ∼5% of people are under treatment. Novel assays have been developed to improve linkage to care by providing more flexible approaches to determine a patient's health status. Other assays have been established to better investigate intrahepatic host-virus interactions to support clinical trials for cure research. This review outlines the clinical and scientific challenges still to be solved and the upcoming methods used to address them.
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Affiliation(s)
- Thomas Tu
- Storr Liver Centre, The Westmead Institute for Medical Research, The University of Sydney at Westmead Hospital, Westmead, New South Wales, Australia; Centre for Infectious Diseases and Microbiology, Sydney Infectious Diseases Institute, The University of Sydney at Westmead Hospital, Westmead, New South Wales, Australia.
| | - Harout Ajoyan
- Storr Liver Centre, The Westmead Institute for Medical Research, The University of Sydney at Westmead Hospital, Westmead, New South Wales, Australia
| | - Jacob George
- Storr Liver Centre, The Westmead Institute for Medical Research, The University of Sydney at Westmead Hospital, Westmead, New South Wales, Australia
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3
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Oshima M, Stappenbeck F, Ohashi H, Iwamoto M, Fukano K, Kusunoki A, Zheng X, Wang F, Morishita R, Aizaki H, Suzuki R, Muramatsu M, Kuramochi K, Sureau C, Parhami F, Watashi K. Selective inhibition of hepatitis B virus internalization by oxysterol derivatives. Biochem Biophys Res Commun 2023; 675:139-145. [PMID: 37473528 DOI: 10.1016/j.bbrc.2023.07.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Revised: 07/04/2023] [Accepted: 07/10/2023] [Indexed: 07/22/2023]
Abstract
Given that the current approved anti-hepatitis B virus (HBV) drugs suppress virus replication and improve hepatitis but cannot eliminate HBV from infected patients, new anti-HBV agents with different mode of action are urgently needed. In this study, we identified a semi-synthetic oxysterol, Oxy185, that can prevent HBV infection in a HepG2-based cell line and primary human hepatocytes. Mechanistically, Oxy185 inhibited the internalization of HBV into cells without affecting virus attachment or replication. We also found that Oxy185 interacted with an HBV entry receptor, sodium taurocholate cotransporting polypeptide (NTCP), and inhibited the oligomerization of NTCP to reduce the efficiency of HBV internalization. Consistent with this mechanism, Oxy185 also inhibited the hepatitis D virus infection, which relies on NTCP-dependent internalization, but not hepatitis A virus infection, and displayed pan-genotypic anti-HBV activity. Following oral administration in mice, Oxy185 showed sustained accumulation in the livers of the mice, along with a favorable liver-to-plasma ratio. Thus, Oxy185 is expected to serve as a useful tool compound in proof-of-principle studies for HBV entry inhibitors with this novel mode of action.
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Affiliation(s)
- Mizuki Oshima
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, 162-8640, Japan; Department of Applied Biological Sciences, Tokyo University of Science, Noda, 278-8510, Japan
| | | | - Hirofumi Ohashi
- Research Center for Drug and Vaccine Development, National Institute of Infectious Diseases, Tokyo, 162-8640, Japan
| | - Masashi Iwamoto
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, 162-8640, Japan
| | - Kento Fukano
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, 162-8640, Japan; Center for Clinical Sciences, National Center for Global Health and Medicine, Tokyo, 162-8655, Japan
| | - Atsuto Kusunoki
- Research Center for Drug and Vaccine Development, National Institute of Infectious Diseases, Tokyo, 162-8640, Japan
| | - Xin Zheng
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, 162-8640, Japan
| | - Feng Wang
- MAX BioPharma, Inc., Santa Monica, CA, 90404, USA
| | - Ryo Morishita
- CellFree Sciences. Co. Ltd., 3 Bunkyo-cho, Matsuyama, Ehime, 790-8577, Japan
| | - Hideki Aizaki
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, 162-8640, Japan
| | - Ryosuke Suzuki
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, 162-8640, Japan
| | - Masamichi Muramatsu
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, 162-8640, Japan
| | - Kouji Kuramochi
- Department of Applied Biological Sciences, Tokyo University of Science, Noda, 278-8510, Japan
| | - Camille Sureau
- Laboratoire de Virologie Moleculaire, Institut National de la Transfusion Sanguine, Paris, 75739, France
| | | | - Koichi Watashi
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, 162-8640, Japan; Department of Applied Biological Sciences, Tokyo University of Science, Noda, 278-8510, Japan; Research Center for Drug and Vaccine Development, National Institute of Infectious Diseases, Tokyo, 162-8640, Japan; MIRAI, JST, Saitama, 332-0012, Japan.
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4
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Kumamoto H, Higashi-Kuwata N, Hayashi S, Das D, Bulut H, Tokuda R, Imoto S, Onitsuka K, Honda Y, Odanaka Y, Shimbara-Matsubayashi S, Haraguchi K, Tanaka Y, Mitsuya H. Synthesis of novel entecavir analogues having 4'-cyano-6''-fluoromethylenecyclopentene skeletons as an aglycone moiety as highly potent and long-acting anti-hepatitis B virus agent. RSC Adv 2023; 13:15999-16011. [PMID: 37265996 PMCID: PMC10230191 DOI: 10.1039/d3ra01750h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 05/09/2023] [Indexed: 06/03/2023] Open
Abstract
Encouraged by our recent findings that 4'-cyano-deoxyguanosine (2), entecavir analogues 4 and 5 are highly potent anti-hepatitis B virus (HBV) agents, we designed and synthesized 6 having a hybridized structure of 4 and 5. The chiral quaternary carbon portion at the 4'-position, which is substituted by cyano- and 5'-hydroxymethyl groups, was stereospecifically constructed by radical-mediated 5-exo-dig mode cyclization of 10. The introduction of the fluorine atom into the 6''-position was achieved by radical-mediated stannylation of sulfide (E)-11 and subsequent electrophilic fluorination of (E)-12. The desired (E)-6 was obtained after the introduction of the guanine base into (E)-18 under Mitsunobu conditions and following global deprotection. The stereoisomer (Z)-6 was also prepared by the same procedure using (Z)-12. Compound (E)-6 showed highly potent anti-HBV activity (EC50 = 1.2 nM) with favorable cytotoxicity (CC50 = 93 μM).
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Affiliation(s)
- Hiroki Kumamoto
- Department of Pharmaceutical Sciences, Nihon Pharmaceutical University Saitama Japan
| | - Nobuyo Higashi-Kuwata
- Department of Refractory Viral Infection, National Center for Global Health & Medicine Research Institute Tokyo Japan
| | - Sanae Hayashi
- Department of Gastroenterology and Hepatology, Faculty of Life Sciences, Kumamoto University Kumamoto Japan
| | - Debananda Das
- Experimental Retrovirology Section, HIV and AIDS Malignancy Branch, National Cancer Institute, National Institutes of Health Bethesda MD USA
| | - Haydar Bulut
- Experimental Retrovirology Section, HIV and AIDS Malignancy Branch, National Cancer Institute, National Institutes of Health Bethesda MD USA
| | - Ryoh Tokuda
- Faculty of Pharmaceutical Sciences, Sojo University Kumamoto Japan
| | - Shuhei Imoto
- Faculty of Pharmaceutical Sciences, Sojo University Kumamoto Japan
| | - Kengo Onitsuka
- Department of Refractory Viral Infection, National Center for Global Health & Medicine Research Institute Tokyo Japan
| | - Yuka Honda
- School of Pharmacy, Showa University Tokyo Japan
| | - Yuki Odanaka
- School of Pharmacy, Showa University Tokyo Japan
| | | | - Kazuhiro Haraguchi
- Department of Pharmaceutical Sciences, Nihon Pharmaceutical University Saitama Japan
| | - Yasuhito Tanaka
- Department of Gastroenterology and Hepatology, Faculty of Life Sciences, Kumamoto University Kumamoto Japan
| | - Hiroaki Mitsuya
- Department of Refractory Viral Infection, National Center for Global Health & Medicine Research Institute Tokyo Japan
- Experimental Retrovirology Section, HIV and AIDS Malignancy Branch, National Cancer Institute, National Institutes of Health Bethesda MD USA
- Department of Clinical Sciences, Kumamoto University Hospital Kumamoto Japan
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5
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Toyoda T, Wang Y, Wen Y, Tanaka Y. Fluorescence-based biochemical analysis of human hepatitis B virus reverse transcriptase activity. Anal Biochem 2020; 597:113642. [PMID: 32171777 DOI: 10.1016/j.ab.2020.113642] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 02/04/2020] [Accepted: 02/18/2020] [Indexed: 12/14/2022]
Abstract
Although the unique mechanism by which hepatitis B virus (HBV) polymerase primes reverse transcription is now well-characterized, the subsequent elongation process remains poorly understood. Reverse transcriptase (RT)-RNase H sequences from polymerase amino acid 304 (the C-terminal part of spacer domain) to 843 were expressed in Escherichia coli and purified partially. RT elongation activity was investigated using the fluorescent-tagged primer and homopolymeric RNA templates. RT elongation activity depended on both Mg2+ and Mn2+, and had low affinity for purine deoxynucleotides, which may be related with the success of adefovir, tenofovir, and entecavir. However, the polymerization rate was lower than that of human immunodeficiency virus RT. All HBV genotypes displayed similar RT activity, except for genotype B, which demonstrated increased elongation activity.
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Affiliation(s)
- Tetsuya Toyoda
- Choju Medical Institute, Fukushimura Hospital, 19-14 Azayamanaka, Noyori-Cho, Toyohashi, Aichi, 441-8124, Japan.
| | - Yongxiang Wang
- Key Laboratory of Medical Molecular Virology, Institute of Medical Microbiology, Shanghai Medical College, Fudan University, Shanghai, 200032, PR China
| | - Yumei Wen
- Key Laboratory of Medical Molecular Virology, Institute of Medical Microbiology, Shanghai Medical College, Fudan University, Shanghai, 200032, PR China
| | - Yasuhito Tanaka
- Department of Virology and Liver Unit, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
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6
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Structural features in common of HBV and HIV-1 resistance against chirally-distinct nucleoside analogues entecavir and lamivudine. Sci Rep 2020; 10:3021. [PMID: 32080249 PMCID: PMC7033138 DOI: 10.1038/s41598-020-59775-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Accepted: 02/04/2020] [Indexed: 12/17/2022] Open
Abstract
Chronic hepatitis B virus (HBV) infection is a major public health problem that affects millions of people worldwide. Nucleoside analogue reverse transcriptase (RT) inhibitors, such as entecavir (ETV) and lamivudine (3TC), serve as crucial anti-HBV drugs. However, structural studies of HBV RT have been hampered due to its unexpectedly poor solubility. Here, we show that human immunodeficiency virus type-1 (HIV-1) with HBV-associated amino acid substitutions Y115F/F116Y/Q151M in its RT (HIVY115F/F116Y/Q151M) is highly susceptible to ETV and 3TC. Additionally, we experimentally simulated previously reported ETV/3TC resistance for HBV using HIVY115F/F116Y/Q151M with F160M/M184V (L180M/M204V in HBV RT) substituted. We determined crystal structures for HIV-1 RTY115F/F116Y/Q151M:DNA complexed with 3TC-triphosphate (3TC-TP)/ETV-triphosphate (ETV-TP)/dCTP/dGTP. These structures revealed an atypically tight binding conformation of 3TC-TP, where the Met184 side-chain is pushed away by the oxathiolane of 3TC-TP and exocyclic methylene of ETV-TP. Structural analysis of RTY115F/F116Y/Q151M/F160M/M184V:DNA:3TC-TP also demonstrated that the loosely bound 3TC-TP is misaligned at the active site to prevent a steric clash with the side chain γ-methyl of Val184. These findings shed light on the common structural mechanism of HBV and HIV-1 resistance to 3TC and ETV and should aid in the design of new agents to overcome drug resistance to 3TC and ETV.
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7
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CMCdG, a Novel Nucleoside Analog with Favorable Safety Features, Exerts Potent Activity against Wild-Type and Entecavir-Resistant Hepatitis B Virus. Antimicrob Agents Chemother 2019; 63:AAC.02143-18. [PMID: 30670420 DOI: 10.1128/aac.02143-18] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 01/10/2019] [Indexed: 02/07/2023] Open
Abstract
We designed, synthesized, and characterized a novel nucleoside analog, (1S,3S,5S)-3-(2-amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-5-hydroxy-1-(hydroxymethyl)-2-methylene-cyclopentanecarbonitrile, or 4'-cyano-methylenecarbocyclic-2'-deoxyguanosine (CMCdG), and evaluated its anti-hepatitis B virus (anti-HBV) activity, safety, and related features. CMCdG's in vitro activity was determined using quantitative PCR and Southern blotting assays, and its cytotoxicity was determined with a 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay, while its in vivo activity and safety were determined in human liver-chimeric mice infected with wild-type HBV genotype Ce (HBVWT Ce) and an entecavir (ETV)-resistant HBV variant containing the amino acid substitutions L180M, S202G, and M204V (HBVETV-R L180M/S202G/M204V). CMCdG potently inhibited HBV production in HepG2.2.15 cells (50% inhibitory concentration [IC50], ∼30 nM) and HBVWT Ce plasmid-transfected Huh7 cells (IC50, 206 nM) and efficiently suppressed ETV-resistant HBVETV-R L180M/S202G/M204V (IC50, 2,657 nM), while it showed no or little cytotoxicity (50% cytotoxic concentration, >500 μM in most hepatocytic cells examined). Two-week peroral administration of CMCdG (1 mg/kg of body weight/day once a day [q.d.]) to HBVWT Ce-infected human liver-chimeric mice reduced the level of viremia by ∼2 logs. CMCdG also reduced the level of HBVETV-R L180M/S202G/M204V viremia by ∼1 log in HBVETV-R L180M/S202G/M204V-infected human liver-chimeric mice, while ETV (1 mg/kg/day q.d.) completely failed to reduce the viremia. None of the CMCdG-treated mice had significant drug-related changes in body weights or serum human albumin levels. Structural analyses using homology modeling, semiempirical quantum methods, and molecular dynamics revealed that although ETV triphosphate (TP) forms good van der Waals contacts with L180 and M204 of HBVWT Ce reverse transcriptase (RT), its contacts with the M180 substitution are totally lost in the HBVETV-R L180M/S202G/M204V RT complex. However, CMCdG-TP retains good contacts with both the HBVWT Ce RT and HBVETV-R L180M/S202G/M204V RT complexes. The present data warrant further studies toward the development of CMCdG as a potential therapeutic for patients infected with drug-resistant HBV and shed light on the further development of more potent and safer anti-HBV agents.
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8
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Weising S, Sterrenberg V, Schols D, Meier C. Synthesis and Antiviral Evaluation of TriPPPro-AbacavirTP, TriPPPro-CarbovirTP, and Their 1′,2′-cis-Disubstituted Analogues. ChemMedChem 2018; 13:1771-1778. [DOI: 10.1002/cmdc.201800361] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Indexed: 11/09/2022]
Affiliation(s)
- Simon Weising
- University of Hamburg; Faculty of Sciences; Department Chemistry; Organic Chemistry; Martin-Luther-King Platz 6 20146 Hamburg Germany
| | - Vincente Sterrenberg
- University of Hamburg; Faculty of Sciences; Department Chemistry; Organic Chemistry; Martin-Luther-King Platz 6 20146 Hamburg Germany
| | - Dominique Schols
- Katholieke Universiteit Leuven; Rega Institute for Medical Research; Herestraat 49 3000 Leuven Belgium
| | - Chris Meier
- University of Hamburg; Faculty of Sciences; Department Chemistry; Organic Chemistry; Martin-Luther-King Platz 6 20146 Hamburg Germany
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9
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Song JH, Kim SY, Shin JK, Hong SD, Rim KS, Park HN, Lee JH, Lee YB, Oh SH, Hwang SG. [A Case of Severe Peripheral Polyneuropathy Occurring after Entecavir Treatment in a Hepatitis B Patient]. THE KOREAN JOURNAL OF GASTROENTEROLOGY 2017; 67:216-219. [PMID: 27112249 DOI: 10.4166/kjg.2016.67.4.216] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Entecavir (Baraclude®) is an oral antiviral drug used for the treatment of HBV. Entecavir is a reverse transcriptase inhibitor which prevents the HBV from multiplying. Most common adverse reactions caused by entecavir are headache, fatigue, dizziness, and nausea. Until now, there has been no report of peripheral neuropathy as a side effect associated with entecavir treatment. Herein, we report a case of peripheral neuropathy which probably occurred after treatment with entecavir in a hepatitis B patient. The possibility of the occurrence of this side effect should be carefully taken into consideration when a patient takes a high dose of entecavir for a long period of time or has risk factors for neuropathy at the time of initiating entecavir therapy.
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Affiliation(s)
- Ji Hyun Song
- Division of Gastroenterology and Hepatology, CHA Bundang Medical Center, CHA University, Seongnam, Korea
| | - Si Yeon Kim
- Division of Gastroenterology and Hepatology, CHA Bundang Medical Center, CHA University, Seongnam, Korea
| | - Jae Kyoung Shin
- Department of Internal Medicine, CHA Bundang Medical Center, CHA University, Seongnam, Korea
| | - So Dam Hong
- Department of Internal Medicine, CHA Bundang Medical Center, CHA University, Seongnam, Korea
| | - Kyu Sung Rim
- Division of Gastroenterology and Hepatology, CHA Bundang Medical Center, CHA University, Seongnam, Korea
| | - Ha Na Park
- Division of Gastroenterology and Hepatology, CHA Bundang Medical Center, CHA University, Seongnam, Korea
| | - Joo Ho Lee
- Division of Gastroenterology and Hepatology, CHA Bundang Medical Center, CHA University, Seongnam, Korea
| | - Yun Bin Lee
- Division of Gastroenterology and Hepatology, CHA Bundang Medical Center, CHA University, Seongnam, Korea
| | - Seung Hun Oh
- Department of Neurology, CHA Bundang Medical Center, CHA University, Seongnam, Korea
| | - Seong Gyu Hwang
- Division of Gastroenterology and Hepatology, CHA Bundang Medical Center, CHA University, Seongnam, Korea
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10
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Temporal Progression of Pneumonic Plague in Blood of Nonhuman Primate: A Transcriptomic Analysis. PLoS One 2016; 11:e0151788. [PMID: 27003632 PMCID: PMC4803270 DOI: 10.1371/journal.pone.0151788] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 03/02/2016] [Indexed: 01/07/2023] Open
Abstract
Early identification of impending illness during widespread exposure to a pathogenic agent offers a potential means to initiate treatment during a timeframe when it would be most likely to be effective and has the potential to identify novel therapeutic strategies. The latter could be critical, especially as antibiotic resistance is becoming widespread. In order to examine pre-symptomatic illness, African green monkeys were challenged intranasally with aerosolized Yersinia pestis strain CO92 and blood samples were collected in short intervals from 45 m till 42 h post-exposure. Presenting one of the first genomic investigations of a NHP model challenged by pneumonic plague, whole genome analysis was annotated in silico and validated by qPCR assay. Transcriptomic profiles of blood showed early perturbation with the number of differentially expressed genes increasing until 24 h. By then, Y. pestis had paralyzed the host defense, as suggested by the functional analyses. Early activation of the apoptotic networks possibly facilitated the pathogen to overwhelm the defense mechanisms, despite the activation of the pro-inflammatory mechanism, toll-like receptors and microtubules at the port-of-entry. The overexpressed transcripts encoding an early pro-inflammatory response particularly manifested in active lymphocytes and ubiquitin networks were a potential deviation from the rodent models, which needs further verification. In summary, the present study recognized a pattern of Y. pestis pathogenesis potentially more applicable to the human system. Independent validation using the complementary omics approach with comprehensive evaluation of the organs, such as lungs which showed early bacterial infection, is essential.
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11
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Lv Y, Sun K, Wang T, Wu Y, Li G, Pu W, Mao S. Intermolecular C−N Cross-Coupling Reactions Catalyzed by Tetra-n-butylammonium Iodide: Synthesis of AllylicN-Heterocycles. ASIAN J ORG CHEM 2016. [DOI: 10.1002/ajoc.201500517] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Yunhe Lv
- College of Chemistry and Chemical Engineering; Anyang Normal University; 436 Xian'ge Road Anyang City Henan 455000 China
| | - Kai Sun
- College of Chemistry and Chemical Engineering; Anyang Normal University; 436 Xian'ge Road Anyang City Henan 455000 China
| | - Tingting Wang
- College of Chemistry and Chemical Engineering; Anyang Normal University; 436 Xian'ge Road Anyang City Henan 455000 China
| | - Yingtao Wu
- College of Chemistry and Chemical Engineering; Anyang Normal University; 436 Xian'ge Road Anyang City Henan 455000 China
| | - Gang Li
- College of Chemistry and Chemical Engineering; Anyang Normal University; 436 Xian'ge Road Anyang City Henan 455000 China
| | - Weiya Pu
- College of Chemistry and Chemical Engineering; Anyang Normal University; 436 Xian'ge Road Anyang City Henan 455000 China
| | - Shukuan Mao
- College of Chemistry and Chemical Engineering; Anyang Normal University; 436 Xian'ge Road Anyang City Henan 455000 China
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12
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A novel method for nucleos(t)ide analogues susceptibility assay of hepatitis B virus by viral polymerase transcomplementation. Antiviral Res 2015; 126:99-107. [PMID: 26738784 DOI: 10.1016/j.antiviral.2015.12.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Revised: 12/18/2015] [Accepted: 12/22/2015] [Indexed: 02/06/2023]
Abstract
Nucleos(t)ide analogues (NUCs) susceptibility assay is important for the study of hepatitis B virus (HBV) drug resistance. The purpose of susceptibility assay is to test the sensitivity of a specific HBV variant to NUCs in vitro, by which assesses if and to what extent the mutant virus is resistant to a specific NUC. Among the existing susceptibility assay methods, stable cell line expressing the specific variant is one of the commonly used assessment systems based on its high repeatability. However, establishment of stable cell lines expressing individual variant is laborious and time-consuming. In the present study, we developed a novel strategy for rapidly establishing HBV replicating stable cell lines. We first established an acceptor cell line stably transfected with a polymerase-null HBV 1.1mer genome DNA, then lentiviruses expressing different mutant HBV polymerases were transduced into the acceptor cell line respectively. Stable cell lines replicating HBV DNA with the trans-complemented HBV polymerases were established by antibiotics selection. Lamivudine and entecavir susceptibility data from these polymerase-complementing cell lines were validated by comparing with other assays. Taken together, this transcomplementation strategy for establishment of stable cell lines replicating HBV DNA with clinically isolated HBV polymerase provides a new tool for NUC susceptibility assay of HBV.
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13
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Takamatsu Y, Tanaka Y, Kohgo S, Murakami S, Singh K, Das D, Venzon DJ, Amano M, Higashi-Kuwata N, Aoki M, Delino NS, Hayashi S, Takahashi S, Sukenaga Y, Haraguchi K, Sarafianos SG, Maeda K, Mitsuya H. 4'-modified nucleoside analogs: potent inhibitors active against entecavir-resistant hepatitis B virus. Hepatology 2015; 62:1024-36. [PMID: 26122273 PMCID: PMC4589464 DOI: 10.1002/hep.27962] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 06/24/2015] [Indexed: 12/23/2022]
Abstract
UNLABELLED Certain nucleoside/nucleotide reverse transcriptase (RT) inhibitors (NRTIs) are effective against human immunodeficiency virus type 1 (HIV-1) and hepatitis B virus (HBV). However, both viruses often acquire NRTI resistance, making it crucial to develop more-potent agents that offer profound viral suppression. Here, we report that 4'-C-cyano-2-amino-2'-deoxyadenosine (CAdA) is a novel, highly potent inhibitor of both HBV (half maximal inhibitory concentration [IC50 ] = 0.4 nM) and HIV-1 (IC50 = 0.4 nM). In contrast, the approved anti-HBV NRTI, entecavir (ETV), potently inhibits HBV (IC50 = 0.7 nM), but is much less active against HIV-1 (IC50 = 1,000 nM). Similarly, the highly potent HIV-1 inhibitor, 4'-ethynyl-2-fluoro-2'-deoxyadenosine (EFdA; IC50 = 0.3 nM) is less active against HBV (IC50 = 160 nM). Southern analysis using Huh-7 cells transfected with HBV-containing plasmids demonstrated that CAdA was potent against both wild-type (IC50 = 7.2 nM) and ETV-resistant HBV (IC50 = 69.6 nM for HBVETV-RL180M/S202G/M204V), whereas ETV failed to reduce HBVETV-RL180M/S202G/M204V DNA even at 1 μM. Once-daily peroral administration of CAdA reduced HBVETV-RL180M/S202G/M204V viremia (P = 0.0005) in human-liver-chimeric/ HBVETV-RL180M/S202G/M204V-infected mice, whereas ETV completely failed to reduce HBVETV-RL180M/S202G/M204V viremia. None of the mice had significant drug-related body-weight or serum human-albumin concentration changes. Molecular modeling suggests that a shallower HBV-RT hydrophobic pocket at the polymerase active site can better accommodate the slightly shorter 4'-cyano of CAdA-triphosphate (TP), but not the longer 4'-ethynyl of EFdA-TP. In contrast, the deeper HIV-1-RT pocket can efficiently accommodate the 4'-substitutions of both NRTIs. The ETV-TP's cyclopentyl ring can bind more efficiently at the shallow HBV-RT binding pocket. CONCLUSION These data provide insights on the structural and functional associations of HBV- and HIV-1-RTs and show that CAdA may offer new therapeutic options for HBV patients.
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Affiliation(s)
- Yuki Takamatsu
- Experimental Retrovirology Section, HIV and AIDS Malignancy Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD USA
| | - Yasuhito Tanaka
- Department of Virology & Liver unit, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Satoru Kohgo
- Research Institute & Center for Clinical Sciences, National Center for Global Health and Medicine, Tokyo, Japan,Department of Pharmaceutical Sciences, Nihon Pharmaceutical University, Saitama, Japan
| | - Shuko Murakami
- Department of Virology & Liver unit, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Kamalendra Singh
- Molecular Microbiology & Immunology, Biochemistry, School of Medicine and Bond Life Sciences Center, University of Missouri, Columbia MO
| | - Debananda Das
- Experimental Retrovirology Section, HIV and AIDS Malignancy Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD USA
| | - David J. Venzon
- Biostatistics and Data Management Section, National Cancer Institute, National Institutes of Health, Bethesda, MD USA
| | - Masayuki Amano
- Departments of Hematology, Rheumatology, and Clinical Immunology & Infectious Disease, Kumamoto University Graduate School of Medical Sciences, Kumamoto, Japan
| | - Nobuyo Higashi-Kuwata
- Research Institute & Center for Clinical Sciences, National Center for Global Health and Medicine, Tokyo, Japan
| | - Manabu Aoki
- Experimental Retrovirology Section, HIV and AIDS Malignancy Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD USA,Departments of Hematology, Rheumatology, and Clinical Immunology & Infectious Disease, Kumamoto University Graduate School of Medical Sciences, Kumamoto, Japan,Department of Medical Technology, Kumamoto Health Science University, Kumamoto, Japan
| | - Nicole S. Delino
- Experimental Retrovirology Section, HIV and AIDS Malignancy Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD USA
| | - Sanae Hayashi
- Department of Virology & Liver unit, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Satoru Takahashi
- Department of Experimental Pathology & Tumor Biology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Yoshikazu Sukenaga
- Research Institute & Center for Clinical Sciences, National Center for Global Health and Medicine, Tokyo, Japan
| | - Kazuhiro Haraguchi
- Department of Pharmaceutical Sciences, Nihon Pharmaceutical University, Saitama, Japan
| | - Stefan G. Sarafianos
- Molecular Microbiology & Immunology, Biochemistry, School of Medicine and Bond Life Sciences Center, University of Missouri, Columbia MO
| | - Kenji Maeda
- Experimental Retrovirology Section, HIV and AIDS Malignancy Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD USA,Research Institute & Center for Clinical Sciences, National Center for Global Health and Medicine, Tokyo, Japan,Correspondence should be addressed to: K.M., Postal address: Kenji Maeda, M.D., Ph.D., Research Institute, National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku, Tokyo 162-8655, Phone: +81-3-3202-7181 Facsimile: +81-3-3207-1038,
| | - Hiroaki Mitsuya
- Experimental Retrovirology Section, HIV and AIDS Malignancy Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD USA,Research Institute & Center for Clinical Sciences, National Center for Global Health and Medicine, Tokyo, Japan,Departments of Hematology, Rheumatology, and Clinical Immunology & Infectious Disease, Kumamoto University Graduate School of Medical Sciences, Kumamoto, Japan
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14
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Zhang Q, Han T, Nie CY, Ha FS, Liu L, Liu H. Tenofovir rescue regimen following prior suboptimal response to entecavir and adefovir combination therapy in chronic hepatitis B patients exposed to multiple treatment failures. J Med Virol 2015; 87:1013-21. [PMID: 25716029 DOI: 10.1002/jmv.24153] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/07/2015] [Indexed: 12/16/2022]
Abstract
In clinical practice, establishing a subsequent optimum treatment for chronic hepatitis B patients with a history of multiple NAs treatment failures, including a suboptimal response to a final therapy with combined ETV and ADV, is a complicated but crucial challenge. This study investigated the efficacy and safety of a tenofovir rescue regimen in these patients. A total of six eligible patients were enrolled and were switched to a tenofovir rescue regimen. At baseline, the genotypes and genotypic mutations of the reverse transcriptase and surface gene were determined by ultra-deep pyrosequencing, and further clonal analyses of the reverse transcriptase domain were performed to identify multidrug-resistant HBV strains. In addition, HBV DNA levels, serology, and biochemistry parameters were monitored at baseline and every 3 months, and abdominal ultrasonography was performed at baseline and every 6 months. All patients were confirmed to harbor LAM-related resistant HBV strains. After switching to the tenofovir rescue treatment, all patients had an undetectable level of HBV DNA within 6 months and achieved normalization of the ALT level within 9 months. These virological and biochemical responses persisted until the end of the observation period. None of the patients developed clinical deterioration or any adverse events related to the tenofovir therapy during the median 16.5-month follow-up. In conclusion, the tenofovir rescue regimen can be employed confidently as a highly effective and safe treatment choice following a suboptimal response to ETV plus ADV therapy for a subset of chronic hepatitis B patients with a history of multiple unsuccessful antiviral treatments.
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Affiliation(s)
- Qian Zhang
- The Third Central Clinical College of Tianjin Medical University, Tianjin, China; Department of Hepatology, Tianjin Third Central Hospital, Tianjin, China
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15
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Liu X, Gao Y, Peng J, Xu Y, Wang Y, Zhou N, Xing J, Luo X, Jiang H, Zheng M. TarPred: a web application for predicting therapeutic and side effect targets of chemical compounds. Bioinformatics 2015; 31:2049-51. [PMID: 25686637 DOI: 10.1093/bioinformatics/btv099] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2015] [Accepted: 02/10/2015] [Indexed: 11/14/2022] Open
Abstract
MOTIVATION Discovering the relevant therapeutic targets for drug-like molecules, or their unintended 'off-targets' that predict adverse drug reactions, is a daunting task by experimental approaches alone. There is thus a high demand to develop computational methods capable of detecting these potential interacting targets efficiently. RESULTS As biologically annotated chemical data are becoming increasingly available, it becomes feasible to explore such existing knowledge to identify potential ligand-target interactions. Here, we introduce an online implementation of a recently published computational model for target prediction, TarPred, based on a reference library containing 533 individual targets with 179 807 active ligands. TarPred accepts interactive graphical input or input in the chemical file format of SMILES. Given a query compound structure, it provides the top ranked 30 interacting targets. For each of them, TarPred not only shows the structures of three most similar ligands that are known to interact with the target but also highlights the disease indications associated with the target. This information is useful for understanding the mechanisms of action and toxicities of active compounds and can provide drug repositioning opportunities. AVAILABILITY AND IMPLEMENTATION TarPred is available at: http://www.dddc.ac.cn/tarpred.
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Affiliation(s)
- Xian Liu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China, Department of Applied Mathematics, University of Washington, Seattle, WA 98195-3925, USA and State Key Laboratory of Bioreactor Engineering and Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Yuan Gao
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China, Department of Applied Mathematics, University of Washington, Seattle, WA 98195-3925, USA and State Key Laboratory of Bioreactor Engineering and Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Jianlong Peng
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China, Department of Applied Mathematics, University of Washington, Seattle, WA 98195-3925, USA and State Key Laboratory of Bioreactor Engineering and Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Yuan Xu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China, Department of Applied Mathematics, University of Washington, Seattle, WA 98195-3925, USA and State Key Laboratory of Bioreactor Engineering and Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Yulan Wang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China, Department of Applied Mathematics, University of Washington, Seattle, WA 98195-3925, USA and State Key Laboratory of Bioreactor Engineering and Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Nannan Zhou
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China, Department of Applied Mathematics, University of Washington, Seattle, WA 98195-3925, USA and State Key Laboratory of Bioreactor Engineering and Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Jing Xing
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China, Department of Applied Mathematics, University of Washington, Seattle, WA 98195-3925, USA and State Key Laboratory of Bioreactor Engineering and Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Xiaomin Luo
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China, Department of Applied Mathematics, University of Washington, Seattle, WA 98195-3925, USA and State Key Laboratory of Bioreactor Engineering and Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Hualiang Jiang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China, Department of Applied Mathematics, University of Washington, Seattle, WA 98195-3925, USA and State Key Laboratory of Bioreactor Engineering and Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China, Department of Applied Mathematics, University of Washington, Seattle, WA 98195-3925, USA and State Key Laboratory of Bioreactor Engineering and Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
| | - Mingyue Zheng
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China, Department of Applied Mathematics, University of Washington, Seattle, WA 98195-3925, USA and State Key Laboratory of Bioreactor Engineering and Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China
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16
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Xu H, Wu Q, Peng C, Zhou L. Study on the antiviral activity of San Huang Yi Gan Capsule against hepatitis B virus with seropharmacological method. BMC COMPLEMENTARY AND ALTERNATIVE MEDICINE 2013; 13:239. [PMID: 24073917 PMCID: PMC3849434 DOI: 10.1186/1472-6882-13-239] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Accepted: 09/24/2013] [Indexed: 12/22/2022]
Abstract
Background Seropharmacology arising recently is a novel method of in vitro pharmacological study on Chinese herb using drug-containing animal serum. As seropharmacology possesses the advantages of experiments in vitro and in vivo, it is increasingly applied in pharmacological research on Chinese medicine. However, some issues of seropharmacology remain controversial and need to be clearly defined. San Huang Yi Gan Capsule (SHYGC) is a Chinese herbal formula with antiviral property against hepatitis B virus (HBV), but little is known about the mechanism underlying its anti-HBV activity. The aim of the present study was to elucidate the action mechanism of SHYGC using seropharmacological method and systematically address the methodology of preparing drug-containing serum. Methods New Zealand rabbits were orally administrated SHYGC with various regimens, followed by preparation of SHYGC-containing rabbit sera with a variety of methods. After HBV-producing HepG2 2.2.15 cells were treated with SHYGC-containing sera or entecavir for 9 days, the levels of hepatitis B surface antigen (HBsAg) and HBV DNA and the activity of DNA Polymerase were determined in HepG2 2.2.15 cells-conditioned media. Results An optimally standardized method of preparing drug-containing serum was raised for seropharmacology, with which SHYGC was demonstrated to suppress HBsAg expression, HBV DNA replication and DNA Polymerase activity in a dose-dependent fashion. Conclusions This seropharmacological study shows SHYGC is a potentially powerful anti-HBV agent. Additionally, seropharmacology is a promising pharmacological method with a broad range of advantages, and it can be widely used in biomedical research, if combined with pharmacokinetics.
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17
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Noncompetitive inhibition of hepatitis B virus reverse transcriptase protein priming and DNA synthesis by the nucleoside analog clevudine. Antimicrob Agents Chemother 2013; 57:4181-9. [PMID: 23774432 DOI: 10.1128/aac.00599-13] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
All currently approved antiviral drugs for the treatment of chronic hepatitis B virus (HBV) infection are nucleos(t)ide reverse transcriptase inhibitors (NRTI), which inhibit the DNA synthesis activity of the HBV polymerase. The polymerase is a unique reverse transcriptase (RT) that has a novel protein priming activity in which HP initiates viral DNA synthesis using itself as a protein primer. We have determined the ability of NRTI-triphosphates (TP) to inhibit HBV protein priming and their mechanisms of action. While entecavir-TP (a dGTP analog) inhibited protein priming initiated specifically with dGTP, clevudine-TP (a TTP analog) was able to inhibit protein priming independently of the deoxynucleoside triphosphate (dNTP) substrate and without being incorporated into DNA. We next investigated the effect of NRTIs on the second stage of protein priming, wherein two dAMP nucleotides are added to the initial deoxyguanosine nucleotide. The obtained results indicated that clevudine-TP as well as tenofovir DF-DP strongly inhibited the second stage of protein priming. Tenofovir DF-DP was incorporated into the viral DNA primer, whereas clevudine-TP inhibited the second stage of priming without being incorporated. Finally, kinetic analyses using the HBV endogenous polymerase assay revealed that clevudine-TP inhibited DNA chain elongation by HP in a noncompetitive manner. Thus, clevudine-TP appears to have the unique ability to inhibit HBV RT via binding to and distorting the HP active site, sharing properties with both NRTIs and nonnucleoside RT inhibitors.
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18
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Deng XL, Li QL, Guo JJ. Dynamics of lamivudine-resistant hepatitis B virus strains in patients with entecavir rescue therapy. Virus Genes 2013; 47:1-9. [DOI: 10.1007/s11262-013-0915-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2013] [Accepted: 04/15/2013] [Indexed: 01/05/2023]
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19
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Sulfamoylbenzamide derivatives inhibit the assembly of hepatitis B virus nucleocapsids. J Virol 2013; 87:6931-42. [PMID: 23576513 DOI: 10.1128/jvi.00582-13] [Citation(s) in RCA: 131] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Chronic hepatitis B virus (HBV) infection, a serious public health problem leading to cirrhosis and hepatocellular carcinoma, is currently treated with either pegylated alpha interferon (pegIFN-α) or one of the five nucleos(t)ide analogue viral DNA polymerase inhibitors. However, neither pegIFN-α nor nucleos(t)ide analogues are capable of reliably curing the viral infection. In order to develop novel antiviral drugs against HBV, we established a cell-based screening assay by using an immortalized mouse hepatocyte-derived stable cell line supporting a high level of HBV replication in a tetracycline-inducible manner. Screening of a library consisting of 26,900 small molecules led to the discovery of a series of sulfamoylbenzamide (SBA) derivatives that significantly reduced the amount of cytoplasmic HBV DNA. Structure-activity relationship studies have thus far identified a group of fluorine-substituted SBAs with submicromolar antiviral activity against HBV in human hepatoma cells. Mechanistic analyses reveal that the compounds dose dependently inhibit the formation of pregenomic RNA (pgRNA)-containing nucleocapsids of HBV but not other animal hepadnaviruses, such as woodchuck hepatitis virus (WHV) and duck hepatitis B virus (DHBV). Moreover, heterologous genetic complementation studies of capsid protein, DNA polymerase, and pgRNA between HBV and WHV suggest that HBV capsid protein confers sensitivity to the SBAs. In summary, SBAs represent a novel chemical entity with superior activity and a unique antiviral mechanism and are thus warranted for further development as novel antiviral therapeutics for the treatment of chronic hepatitis B.
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Sadler MD, Coffin CS, Lee SS. Entecavir for the treatment of patients with hepatitis B virus-related decompensated cirrhosis. Expert Opin Pharmacother 2013; 14:1363-9. [PMID: 23557465 DOI: 10.1517/14656566.2013.786701] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
INTRODUCTION Chronic hepatitis B (CHB) infection is common and carries a significant risk for the development of cirrhosis, hepatic decompensation, and hepatocellular carcinoma. The goal of treatment in patients with CHB-related decompensated cirrhosis is to improve hepatic dysfunction and reduce mortality through the inhibition of viral replication. Several studies have now shown nucleot(s)ide analogs to be safe and effective in decompensated cirrhosis due to CHB. AREAS COVERED A review of the evidence for the use of entecavir in the treatment of decompensated hepatitis B cirrhosis is discussed. EXPERT OPINION Entecavir is an effective treatment option for most patients with CHB. In treatment naïve patients, it is a potent antiviral agent with a very low resistance rate, making it an excellent option for the treatment of decompensated hepatitis B cirrhosis. The use of entecavir monotherapy in patients with a known rtM204V lamivudine-resistant mutation should be avoided due to increased risk of developing entecavir resistance and failing treatment.
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Affiliation(s)
- Matthew D Sadler
- University of Calgary Liver Unit, 3330 Hospital Dr NW, Calgary, AB, T2N 4N1, Canada
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21
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Qin B, He T, Chen Z, Xu W, Pan G, Tu C. A novel method for the analysis of drug-resistant phenotypes of hepatitis B virus. Int J Mol Med 2013; 31:975-81. [PMID: 23403838 DOI: 10.3892/ijmm.2013.1277] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 01/14/2013] [Indexed: 11/06/2022] Open
Abstract
Chronic hepatitis B virus (CHB) infection is a major cause of cirrhosis and hepatocellular carcinoma. Nucleoside analogs (NAs) are popularly used to treat chronic hepatitis B virus (HBV) infections; however, the anti-HBV effect is attenuated by drug-resistant viral mutations selected during long-term antiviral therapy. The timely analysis of drug-resistance mutations is essential in order to adjust treatment regimes. In this study, a T1699C substitution was introduced into the x gene of pHBV1.3 to generate an additional XhoI site, termed pHBV1.3‑XhoI, which is a nonsense mutation and does not influence protein expression, HBV replication ability, or NA susceptibility. Based on co-transfection with weak or non-replicative HBV plasmids and pHBV1.3-XhoI or pHBV1.3 and -XhoI-P-null plasmids into hepatocellular carcinoma cells, PCR was used to amplify 1176‑bp segments of T/C1699 using the isolated HBV encapsulated DNA as a template, modified by XhoI digestion and subjected to agarose gel electrophoresis. Different bands composed of different virions were used to distinguish the replication capacities of the plasmids. Our results demonstrated no significant effects when different virions co-existed. A novel resistance test method was developed by co-transfection with pHBV1.3-XhoI and -rtL180M/M204V and treatment with various NA concentrations. Different bands composed of pHBV1.3-XhoI or -rtL180M/M204V were used to distinguish NA susceptibility. The bands composed of pHBV1.3 were more sharply reduced by lamivudine (LMV) than -rtL180M/M204V. The data demonstrate that the method established in our study may be used for the analysis of drug-resistant phenotypes at the cellular level.
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Affiliation(s)
- Bo Qin
- Shaoxing Centre for Disease Control and Prevention, Shaoxing, Zhejiang, PR China.
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Zheng LY, Zang LM, Yang QH, Yu WQ, Fang XZ, Zhang YH, Zhao XJ, Wan N, Zhang YT, Wang QD, Chang JB. Anti-hepatitis B virus activity of α-DDB–DU, a novel nucleoside analogue, in vitro and in vivo. Eur J Pharmacol 2013; 702:258-63. [DOI: 10.1016/j.ejphar.2013.01.059] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Revised: 01/25/2013] [Accepted: 01/31/2013] [Indexed: 11/24/2022]
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23
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Yim HJ, Seo YS, Yoon EL, Kim CW, Lee CD, Park SH, Lee MS, Park CK, Chae HB, Kim MY, Baik SK, Kim YS, Kim JH, Lee JI, Lee JW, Hong SP, Um SH. Adding adefovir vs. switching to entecavir for lamivudine-resistant chronic hepatitis B (ACE study): a 2-year follow-up randomized controlled trial. Liver Int 2013; 33:244-54. [PMID: 23295056 DOI: 10.1111/liv.12036] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2012] [Accepted: 10/15/2012] [Indexed: 12/14/2022]
Abstract
BACKGROUND Management of lamivudine-resistant chronic hepatitis B (CHB) remains challenging, as inappropriate choice of treatment may cause multidrug resistance. Until now, randomized trials directly comparing adding adefovir and switching to entecavir monotherapy have not been reported. AIMS This multicentre prospective randomized study was designed to compare the efficacy of these two strategies. METHODS Two hundred and nineteen lamivudine-resistant CHB patients were randomized to either adefovir-lamivudine combination group or entecavir monotherapy group (n = 110 vs. 109), and followed up for 24 months. RESULTS One hundred and eighty patients completed this study. At month 24, virological response rate [hepatitis B virus (HBV) DNA <60 IU/ml] was higher in the adefovir-lamivudine combination group compared with entecavir group (56.7% vs. 40%, P = 0.025), although biochemical and serological response rates were not significantly different. Genotypic resistance (9.2% vs. 24.6%, P = 0.005) and combined viral breakthrough (2.0% vs. 17.6%, P < 0.001) were more frequent in the entecavir group. However, by subgroup analysis, virological response rates were not significantly different between the two therapies in HBeAg-positive patients (44.9% vs. 35.7%, P = 0.268) or in patients with high baseline HBV DNA (≥7 log IU/ml) (40.7% vs. 31.3%, P = 0.320) at month 24. CONCLUSION This study showed that adefovir-lamivudine combination provides significantly higher antiviral efficacy and the lower resistance rate compared with the entecavir monotherapy in the management of lamivudine-resistant CHB. However, it had limited efficacy in HBeAg-positive patients or in patients with high baseline HBV DNA.
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Affiliation(s)
- Hyung Joon Yim
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Korea University Ansan Hospital, Ansan, Korea
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Zoulim F, Locarnini S. Optimal management of chronic hepatitis B patients with treatment failure and antiviral drug resistance. Liver Int 2013; 33 Suppl 1:116-24. [PMID: 23286855 DOI: 10.1111/liv.12069] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
The management of treatment failure in patients with chronic hepatitis B, remains a clinical concern. Incomplete viral suppression and the emergence of drug resistance are key determinants of treatment failure. The correct choice of a potent first-line therapy to achieve sustained long-term suppression of viral replication provides the best chance of preventing treatment failure and drug resistance. Clinical studies have demonstrated that drugs with a high barrier to resistance have significantly lower rates of resistance compared with those with a low barrier to resistance. Management of treatment failure requires precise clinical and virological monitoring as well as early treatment intervention with appropriate noncross-resistant antivirals. Long-term surveillance of treatment efficacy and possible emergence of drug resistance is necessary in patients who have been sequentially treated with multiple antivirals. The identification of novel treatment targets remains a major research goal to improve the efficacy of current antiviral therapy through combination therapy regimens.
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Affiliation(s)
- Fabien Zoulim
- INSERM, U1052, Cancer Research Center of Lyon, Lyon University, Lyon, France.
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Yang Q, Zhao X, Zang L, Fang X, Zhao J, Yang X, Wang Q, Zheng L, Chang J. Anti-hepatitis B virus activities of α-DDB-FNC, a novel nucleoside-biphenyldicarboxylate compound in cells and ducks, and its anti-immunological liver injury effect in mice. Antiviral Res 2012; 96:333-9. [PMID: 23098744 DOI: 10.1016/j.antiviral.2012.10.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2012] [Revised: 10/13/2012] [Accepted: 10/15/2012] [Indexed: 12/31/2022]
Abstract
Infection with hepatitis B virus (HBV) continues to be a major global cause of acute and chronic liver disease with high mortality. Herein, we examined both the anti-HBV and hepatoprotective activity of α-DDB-FNC. In human HBV-transfected liver cell line HepG2.2.15, α-DDB-FNC effectively suppressed the secretion of HBV antigens in a time and dose-dependent manner with 25.11% inhibition on HBeAg and 43.68% on HBsAg at 2.5 μM on day 9. Consistent with the HBV antigen reduction, α-DDB-FNC (2.5 μM) also reduced HBV DNA level by 77.74% extracellularly and 78.94% intracellularly on day 9. In the duck hepatitis B virus (DHBV) infected ducks, after α-DDB-FNC was given once daily for 10 days, the serum and liver DHBV DNA levels were reduced markedly with 96.81% and 97.21% at 10 mgkg(-1) on day 10, respectively. In Con A-induced immunological liver-injury mice, α-DDB-FNC significantly inhibited the elevation of serum ALT, AST, TBiL and liver MDA, NO levels. Furthermore, significant improvement of the liver was observed after α-DDB-FNC treatment both in ducks and mice, as evaluated by the histopathological analysis. In conclusion, our results demonstrated that α-DDB-FNC possesses both antiviral activity against HBV and hepatoprotective effect to Con A-induced liver-injury mice.
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Affiliation(s)
- Qinghua Yang
- The College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450001, PR China
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Comparison of rescue strategies in lamivudine-resistant patients with chronic hepatitis B. Antiviral Res 2012; 96:100-4. [PMID: 22960601 DOI: 10.1016/j.antiviral.2012.08.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Revised: 08/21/2012] [Accepted: 08/23/2012] [Indexed: 12/12/2022]
Abstract
Lamivudine (LAM) resistance now poses a major problem in the management of patients with chronic hepatitis B virus (HBV) infection. We retrospectively collected clinical data on chronic HBV-infected patients who had developed LAM resistance under de novo LAM monotherapy and subsequently took nucleos(t)ide analogs as rescue strategy in our hospital. From initiation of rescue therapies to January 2012, incidence of antiviral drug resistance was 23.67%, 18%, 6.94% and 0% (P=0.007) in the group of switching to adefovir dipivoxil (ADV) monotherapy, switching to entecavir (ETV) monotherapy, adding on ADV and switching to combination of ADV and ETV. At month 12, the median levels of serum HBV DNA were respectively 9300IU/mL, 4648IU/mL, 2054IU/mL and 100IU/mL (P<0.001), and the cumulative rates of serum ALT normalization were respectively 75%, 84%, 93% and 100% (P=0.003). Additionally, the strategy of switching to ADV monotherapy induced more single rtA181T mutations. In conclusion, switching to ADV monotherapy has been widely used in real-world clinical practice in China, however, due to the high incidence of drug resistance, switching to neither ADV nor ETV monotherapy is optimal when LAM resistance occurs; combination of ADV and ETV is most effective, whereas the strategy of adding on ADV is rational for most of LAM-resistant Chinese patients with chronic hepatitis B.
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Abstract
Antiviral therapy of chronic hepatitis B remains a clinical challenge. The primary goal of therapy is to prevent liver disease progression. Because of the mechanism of viral persistence in infected hepatocytes, long-term antiviral therapy is needed in the majority of patients. Incomplete viral suppression and emergence of drug resistance is a major concern. The correct choice of a first-line potent therapy to achieve sustained long-term suppression of viral replication provides the best chance of preventing treatment failure and drug resistance. Clinical studies have demonstrated that drugs with a high barrier to resistance, such as entecavir and tenofovir, have significantly lower rates of resistance when compared with those with a low barrier to resistance such as lamivudine, adefovir, or telbivudine. Management of treatment failure requires a precise clinical and accurate virologic monitoring as well as an early treatment intervention with appropriate complementary drugs with respect to their cross-resistance profile. Long-term surveillance for treatment efficacy and possible emergence of drug resistance is necessary for those patients who have been sequentially treated with multiple antivirals. Finally, the identification of novel treatment targets remains a major research challenge to improve the efficacy of current antiviral therapy.
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Affiliation(s)
- Fabien Zoulim
- INSERM, U1052, Cancer Research Center of Lyon, 69003 Lyon, France.
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28
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Devi U, Locarnini S. Role of Resistance Testing During Oral Antiviral Therapy of Chronic Hepatitis B. ACTA ACUST UNITED AC 2012. [DOI: 10.1007/s11901-012-0132-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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van Maarseveen NM, Wensing AM, de Jong D, Beilhartz GL, Obikhod A, Tao S, Pingen M, Arends JE, Hoepelman AI, Schinazi RF, Götte M, Nijhuis M. Telbivudine exerts no antiviral activity against HIV-1 in vitro and in humans. Antivir Ther 2012; 16:1123-30. [PMID: 22024528 DOI: 10.3851/imp1912] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND HIV-HBV-coinfected individuals who need to be treated only for their HBV infection have limited therapeutic options, since most approved anti-HBV agents have a risk of selecting for drug-resistant HIV mutants. In vivo data are inconclusive as to whether telbivudine (LdT) may exert antiviral effects against HIV. Thus, we investigated in further detail the antiviral activity and the biochemical properties of LdT against HIV-1. METHODS To investigate the activity of LdT against HIV-1 in humans we analysed viral dynamics and genotypic and phenotypic resistance development in two HIV-HBV-coinfected individuals with no prior antiviral exposure. To investigate the activity of LdT against HIV-1 in vitro, LdT susceptibility for HIV-1 wild-type strains as well as drug-resistant strains was determined. Furthermore, we studied whether the 5'-triphosphate form of LdT (LdT-TP) can act as a substrate for wild-type HIV-1 RT. RESULTS In the two patients studied, LdT treatment did not result in a significant decline of HIV-1 RNA load nor in selection of genotypic or phenotypic resistance in HIV-1 RT. In vitro virological analyses demonstrated that LdT had no activity (50% effective concentration >100 μM) against wild type HIV and drug-resistant variants. Biochemical analyses demonstrated that LdT-TP is not incorporated by wild-type HIV-1 RT. CONCLUSIONS Based on the in vivo and in vitro evidence obtained in this study, we conclude that LdT has no anti-HIV-1 activity and is currently the only selective anti-HBV agent among the five FDA-approved nucleoside/nucleotide analogues for treatment of HBV infections in HIV-infected individuals.
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Affiliation(s)
- Noortje M van Maarseveen
- Department of Medical Microbiology, Virology, University Medical Center Utrecht, Utrecht, The Netherlands.
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Gish R, Jia JD, Locarnini S, Zoulim F. Selection of chronic hepatitis B therapy with high barrier to resistance. THE LANCET. INFECTIOUS DISEASES 2012; 12:341-53. [PMID: 22326017 DOI: 10.1016/s1473-3099(11)70314-0] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Antiviral drug resistance is a crucial factor that frequently determines the success of long-term therapy for chronic hepatitis B. The development of resistance to nucleos(t)ide analogues has been associated with exacerbations in liver disease and increased risk of emergence of multidrug resistance. The selection of a potent nucleos(t)ide analogue with a high barrier to resistance as a first-line therapy, such as entecavir or tenofovir, provides the best chance of achieving long-term treatment goals and should be used wherever possible. The barrier to resistance of a given nucleos(t)ide analogue is influenced by genetic barrier, drug potency, patient adherence, pharmacological barrier, viral fitness, mechanism of action, and cross-resistance. In countries with limited health-care resources, the selection of a therapy with a high barrier to resistance is not always possible and alternative strategies for preventing resistance might be needed, although limited data are available to support these strategies.
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Affiliation(s)
- Robert Gish
- Center for Hepatobiliary Disease and Abdominal Transplantation, UC San Diego Health System, San Diego, CA, USA
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31
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Abstract
Despite the effective management of most cases of hepatitis B virus (HBV) infection, there is still much room for improvement in the treatment of more severe cases of hepatitis B, such as those occurring in patients with decompensated cirrhosis, in transplanted subjects, and in patients with exacerbations of HBV infection. Among the treatments currently approved for the therapy of hepatitis B, entecavir determines a rapid suppression of viral load. This drug is also associated with a high genetic barrier and an overall favorable safety profile. This review provides an overview of recent evidence related to the use of entecavir in the management of the most severe forms of hepatitis B. The results obtained for this drug in real-life clinical practice are also reviewed.
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Affiliation(s)
- Rodolfo Sacco
- Department of Gastroenterology, Pisa University Hospital, Pisa, Italy
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32
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Zheng L, Wang Q, Yang X, Guo X, Chen L, Tao L, Dong L, Li Y, An H, Yu X, Wang Q, Chang J. Antiviral activity of FNC, 2′-deoxy-2′-β-fluoro-4′-azidocytidine, against human and duck HBV replication. Antivir Ther 2012; 17:679-87. [DOI: 10.3851/imp2094] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/29/2011] [Indexed: 10/28/2022]
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Rodriguez-Frías F, Tabernero D, Quer J, Esteban JI, Ortega I, Domingo E, Cubero M, Camós S, Ferrer-Costa C, Sánchez A, Jardí R, Schaper M, Homs M, Garcia-Cehic D, Guardia J, Esteban R, Buti M. Ultra-deep pyrosequencing detects conserved genomic sites and quantifies linkage of drug-resistant amino acid changes in the hepatitis B virus genome. PLoS One 2012; 7:e37874. [PMID: 22666402 PMCID: PMC3364280 DOI: 10.1371/journal.pone.0037874] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Accepted: 04/25/2012] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Selection of amino acid substitutions associated with resistance to nucleos(t)ide-analog (NA) therapy in the hepatitis B virus (HBV) reverse transcriptase (RT) and their combination in a single viral genome complicates treatment of chronic HBV infection and may affect the overlapping surface coding region. In this study, the variability of an overlapping polymerase-surface region, critical for NA resistance, is investigated before treatment and under antiviral therapy, with assessment of NA-resistant amino acid changes simultaneously occurring in the same genome (linkage analysis) and their influence on the surface coding region. METHODOLOGY/PRINCIPAL FINDINGS Serum samples obtained from chronic HBV-infected patients at pre-treatment and during sequential NA treatment with lamivudine, adefovir, and entecavir were analyzed by ultra-deep pyrosequencing (UDPS) using the GS-FLX platform (454 Life Sciences-Roche). The pre-treatment HBV quasispecies was not enriched with NA-resistant substitutions. The frequencies of this type of substitutions at pre-treatment did not predict the frequencies observed during lamivudine treatment. On linkage analysis of the RT region studied, NA-resistant HBV variants (except for rtA181T) were present in combinations of amino acid substitutions that increased in complexity after viral breakthrough to entecavir, at which time the combined variant rtL180M-S202G-M204V-V207I predominated. In the overlapping surface region, NA-resistant substitutions caused selection of stop codons in a significant percentage of sequences both at pre-treatment and during sequential treatment; the rtA181T substitution, related to sW172stop, predominated during treatment with lamivudine and adefovir. A highly conserved RT residue (rtL155), even more conserved than the essential residues in the RT catalytic motif YMDD, was identified in all samples. CONCLUSIONS UDPS methodology enabled quantification of HBV quasispecies variants, even those harboring complex combinations of amino acid changes. The high percentage of potentially defective genomes, especially in the surface region, suggests effective trans-complementation of these variants.
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Affiliation(s)
- Francisco Rodriguez-Frías
- Biochemistry Department, Hospital Universitari Vall d'Hebron, Vall d'Hebron Institut de Recerca, Universitat Autònoma de Barcelona, Barcelona, Spain.
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Brown JA, Pack LR, Fowler JD, Suo Z. Presteady state kinetic investigation of the incorporation of anti-hepatitis B nucleotide analogues catalyzed by noncanonical human DNA polymerases. Chem Res Toxicol 2011; 25:225-33. [PMID: 22132702 DOI: 10.1021/tx200458s] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Antiviral nucleoside analogues have been developed to inhibit the enzymatic activities of the hepatitis B virus (HBV) polymerase, thereby preventing the replication and production of HBV. However, the usage of these analogues can be limited by drug toxicity because the 5'-triphosphates of these nucleoside analogues (nucleotide analogues) are potential substrates for human DNA polymerases to incorporate into host DNA. Although they are poor substrates for human replicative DNA polymerases, it remains to be established whether these nucleotide analogues are substrates for the recently discovered human X- and Y-family DNA polymerases. Using presteady state kinetic techniques, we have measured the substrate specificity values for human DNA polymerases β, λ, η, ι, κ, and Rev1 incorporating the active forms of the following anti-HBV nucleoside analogues approved for clinical use: adefovir, tenofovir, lamivudine, telbivudine, and entecavir. Compared to the incorporation of a natural nucleotide, most of the nucleotide analogues were incorporated less efficiently (2 to >122,000) by the six human DNA polymerases. In addition, the potential for entecavir and telbivudine, two drugs which possess a 3'-hydroxyl, to become embedded into human DNA was examined by primer extension and DNA ligation assays. These results suggested that telbivudine functions as a chain terminator, while entecavir was efficiently extended by the six enzymes and was a substrate for human DNA ligase I. Our findings suggested that incorporation of anti-HBV nucleotide analogues catalyzed by human X- and Y-family polymerases may contribute to clinical toxicity.
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Affiliation(s)
- Jessica A Brown
- Department of Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
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Rawal RK, Singh US, Gadthula S, Chu CK. Synthesis of Entecavir and Its Novel Class of Analogs. ACTA ACUST UNITED AC 2011; Chapter 14:Unit 14.7.1-17. [DOI: 10.1002/0471142700.nc1407s47] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
| | | | | | - Chung K. Chu
- The University of Georgia College of Pharmacy Athens Georgia
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Hu JL, Cui J, Guo JJ, Zhang WL, Cai XF, Yuan ZW, Li QL, Deng XY, Zeng AZ, Hu Y, Tang N, Huang AL. Phenotypic assay of a hepatitis B virus strain carrying an rtS246T variant using a new strategy. J Med Virol 2011; 84:34-43. [PMID: 22052677 DOI: 10.1002/jmv.22260] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/21/2011] [Indexed: 12/13/2022]
Abstract
Phenotypic assays of hepatitis B virus (HBV) play an important role in research related to the problem of drug resistance that emerges during long-term nucleot(s)ide therapy in patients with chronic hepatitis B. Most of the phenotypic assay systems that are available currently rely on the transfection of recombinant replication-competent HBV DNA into hepatoma cell lines. Cloning clinical HBV isolates using conventional digestion-and-ligation techniques to generate replication-competent recombinants can be very difficult because of the sequence heterogeneity and unique structure of the HBV genome. In this study, a new strategy for constructing an HBV 1.1× recombinant was developed. The core of this strategy is the "fragment substitution reaction" (FSR). FSR allows PCR fragments to be cloned without digestion or ligation, providing a new tool for cloning fragments or genomes amplified from serum HBV DNA, and therefore making the assay of HBV phenotypes more convenient. Using this strategy, a phenotypic assay was performed on an HBV strain carrying an rtS246T variant isolated from a patient with chronic hepatitis B that was only responsive partially to entecavir therapy. The results indicated that this strain is sensitive to entecavir in vitro.
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Affiliation(s)
- Jie-li Hu
- Institute for Viral Hepatitis, Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Chongqing Medical University, Chongqing, China
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Amini-Bavil-Olyaee S, Herbers U, Luedde T, Trautwein C, Tacke F. Impact of hepatitis B e antigen-suppressing mutations on the replication efficiency of entecavir-resistant hepatitis B virus strains. J Viral Hepat 2011; 18:804-14. [PMID: 20887378 DOI: 10.1111/j.1365-2893.2010.01378.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Hepatitis B e antigen (HBeAg)-negative hepatitis B commonly requires long-term treatment with nucleos(t)ide analogues aiming at persistently suppressing hepatitis B virus (HBV) replication to halt progression of liver disease and prevent complications. Entecavir (ETV) is widely used in HBeAg-negative hepatitis B, but distinct HBV polymerase mutations can confer resistance against ETV, in conjunction with lamivudine resistance. Precore (PC) and basal core promoter (BCP) mutations that underlie HBeAg-negativity enhance replication of lamivudine-resistant mutants. To comprehensively analyse the impact of PC or BCP mutations on viral replication of ETV-resistant HBV mutants, replication-competent HBV constructs were generated harbouring lamivudine resistance (rtM204V/rtL180M, rtM204I) plus ETV resistance (rtS202G, rtS202I or rtT184G) on wild-type (WT)-, PC- and BCP-backgrounds. Functional consequences on viral fitness and susceptibility to antivirals were assessed in vitro. The presence of any ETV resistance drastically reduced viral replication when compared to WT HBV. In rtS202G mutants (plus lamivudine resistance), addition of either PC or BCP mutations moderately enhanced the reduced replication, without reaching WT HBV levels. In rtS202I or rtT184G mutants, PC and BCP mutations did not significantly improve viral fitness. All ETV-resistant constructs, independently of PC or BCP mutations, showed resistance towards ETV and lamivudine, but remained susceptible to tenofovir. Our data demonstrate that HBeAg-suppressing PC or BCP mutations cannot restore the strongly reduced replicative capacity of ETV-resistant HBV mutants to WT level, although they moderately increase replication of rtS202G combination mutants. ETV resistance thereby differs from lamivudine resistance alone, corroborating that ETV is in short term a safe option for HBeAg-negative patients.
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Guan R, Lui HF. Treatment of hepatitis B in decompensated liver cirrhosis. Int J Hepatol 2011; 2011:918017. [PMID: 21994876 PMCID: PMC3170850 DOI: 10.4061/2011/918017] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Accepted: 04/19/2011] [Indexed: 12/12/2022] Open
Abstract
Chronic hepatitis B infection progresses from an asymptomatic persistently infected state to chronic hepatitis, cirrhosis, decompensated liver disease, and/or hepatocellular carcinoma. About 3% of patients with chronic hepatitis develop cirrhosis yearly, and about 5% of individuals with hepatitis B cirrhosis become decompensated annually. The outcome for patients with decompensated cirrhosis is bleak. Lamivudine, the first oral antiviral agent available for hepatitis B treatment is safe and effective and can improve or stabilize liver disease in patients with advanced cirrhosis and viraemia. Viral resistance restricts its prolonged use. Entecavir and tenofovir are newer agents with excellent resistance profile to date. These and some other antiviral agents are being investigated for optimal use in this rather challenging patient group.
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Affiliation(s)
- Richard Guan
- Mount Elizabeth Hospital and Medical Centre, Singapore 228510
| | - Hock Foong Lui
- Gleneagles Hospital and Medical Centre, Singapore 258500
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Cassino L, Benetti S, Fay F, Tanno H, Quarleri J. Unsuccessful therapy with adefovir and entecavir-tenofovir in a patient with chronic hepatitis B infection with previous resistance to lamivudine: a fourteen-year evolution of hepatitis B virus mutations. BMC Infect Dis 2011; 11:178. [PMID: 21696601 PMCID: PMC3135534 DOI: 10.1186/1471-2334-11-178] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Accepted: 06/22/2011] [Indexed: 02/08/2023] Open
Abstract
Background Complex mutants can be selected under sequential selective pressure by HBV therapy. To determine hepatitis B virus genomic evolution during antiviral therapy we characterized the HBV quasi-species in a patient who did no respond to therapy following lamivudine breakthrough for a period of 14 years. Case Presentation The polymerase and precore/core genes were amplified and sequenced at determined intervals in a period of 14 years. HBV viral load and HBeAg/Anti-HBe serological profiles as well as amino transferase levels were also measured. A mixture of lamivudine-resistant genotype A2 HBV strains harboring the rtM204V mutation coexisted in the patient following viral breakthrough to lamivudine. The L180M+M204V dominant mutant displayed strong lamivudine-resistance. As therapy was changed to adefovir, then to entecavir, and finally to entecavir-tenofovir the viral load showed fluctuations but lamivudine-resistant strains continued to be selected, with minor contributions to the HBV quasi-species composition of additional resistance-associated mutations. At the end of the 14-year follow up period, high viral loads were predominant, with viral strains harboring the lamivudine-resistance signature rtL180M+M204V. The precore/core frame A1762T and G1764A double mutation was detected before treatment and remaining in this condition during the entire follow-up. Specific entecavir and tenofovir primary resistance-associated mutations were not detected at any time. Plasma concentrations of tenofovir indicated adequate metabolism of the drug. Conclusions We report the selection of HBV mutants carrying well-defined primary resistance mutations that escaped lamivudine in a fourteen-year follow-up period. With the exception of tenofovir resistance mutations, subsequent unselected primary resistance mutations were detected as minor populations into the HBV quasispecies composition during adefovir or entecavir monotherapies. Although tenofovir is considered an appropriate therapeutic alternative for the treatment of entecavir-unresponsive patients, its use was not effective in the case reported here.
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Affiliation(s)
- Lucila Cassino
- Centro Nacional de Referencia para el SIDA, Departamento de Microbiología, Facultad de Medicina, Universidad de Buenos Aires, Argentina
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40
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Abstract
Currently, there are 7 approved therapies for chronic hepatitis B virus (HBV) infection, an increase from just 3 agents 5 years ago. This review will focus on the pharmacology, potency, and adverse events associated with immunomodulatory agents and nucleos(t)ide analogues, with an emphasis on targets of therapy within the HBV life cycle. We will also offer guidelines for the use of available anti-HBV agents and review the emerging challenges in hepatitis B management, including HBV drug resistance, its management, and the potential role of combination therapy.
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Affiliation(s)
- Debika Bhattacharya
- David Geffen School of Medicine at the University of California, Los Angeles, USA.
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41
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Kim KH, Kim ND, Seong BL. Discovery and development of anti-HBV agents and their resistance. Molecules 2010; 15:5878-908. [PMID: 20802402 PMCID: PMC6257723 DOI: 10.3390/molecules15095878] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2010] [Revised: 08/24/2010] [Accepted: 08/26/2010] [Indexed: 02/07/2023] Open
Abstract
Hepatitis B virus (HBV) infection is a prime cause of liver diseases such as hepatitis, cirrhosis and hepatocellular carcinoma. The current drugs clinically available are nucleot(s)ide analogues that inhibit viral reverse transcriptase activity. Most drugs of this class are reported to have viral resistance with breakthrough. Recent advances in methods for in silico virtual screening of chemical libraries, together with a better understanding of the resistance mechanisms of existing drugs have expedited the discovery and development of novel anti-viral drugs. This review summarizes the current status of knowledge about and viral resistance of HBV drugs, approaches for the development of novel drugs as well as new viral and host targets for future drugs.
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Affiliation(s)
- Kyun-Hwan Kim
- Department of Pharmacology, School of Medicine, and Center for Cancer Research and Diagnostic Medicine, IBST, Konkuk University, Seoul 143-701, Korea
- Research Institute of Medical Sciences, Konkuk University, Seoul 143-701, Korea
- Author to whom correspondence should be addressed; E-Mail: (K.H.K.); Tel.: +82 2 2030 7833; Fax: +82 2 2049 6192; E-Mail: (B.L.S.); Tel.: +82 2 2123 2885; Fax: +82 2 392 3582
| | - Nam Doo Kim
- R&D Center, Equispharm Inc., 11F Gyeonggi Bio-Center, 864-1 Iui-Dong, Yeongtong-gu, Suwon-Shi, Gyeonggi-Do 443-766, Korea
| | - Baik-Lin Seong
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea
- Translational Research Center for Protein Function Control, Yonsei University, Seoul 120-749, Korea
- Author to whom correspondence should be addressed; E-Mail: (K.H.K.); Tel.: +82 2 2030 7833; Fax: +82 2 2049 6192; E-Mail: (B.L.S.); Tel.: +82 2 2123 2885; Fax: +82 2 392 3582
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Abstract
The introduction of nucleos(t)ide analog therapy has seen the emergence of antiviral drug resistance, which has become the main factor limiting the long-term application of these antiviral agents for patients with chronic hepatitis B. The prevention of resistance requires the adoption of strategies that effectively control virus replication and exploit an understanding of the mechanisms and processes that drive the emergence of drug resistance, namely high replication rates, low fidelity of the hepatitis B virus rt/polymerase, selective pressure of the nucleos(t)ide analog, role of replication space (liver turnover), fitness of the mutant, and genetic barrier to the drug.
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Cho SW, Koh KH, Cheong JY, Lee MH, Hong SP, Yoo WD, Kim SO. Low efficacy of entecavir therapy in adefovir-refractory hepatitis B patients with prior lamivudine resistance. J Viral Hepat 2010; 17:171-7. [PMID: 19678894 DOI: 10.1111/j.1365-2893.2009.01161.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
We determined the virologic response, incidence of entecavir resistance, and evolution of lamivudine and adefovir-resistant mutants during entecavir (ETV) therapy in adefovir-refractory patients with prior lamivudine resistance. Forty adefovir-refractory chronic hepatitis B patients with prior lamivudine resistance who had received entecavir for > or = 6 months were included and monitored for virologic response and entecavir resistance. Ten per cent of patients achieved HBV DNA < 50 copies/mL by PCR after 24 weeks of ETV therapy, and an initial virologic response was observed in 12 of 40 patients (30%). Higher pretreatment ALT (P = 0.039) and the presence of the rtL180M mutation (P = 0.038) were associated with an initial virologic response. During a mean follow-up of 11.4 months, four patients (10%) experienced virologic breakthrough, while ETV-resistant mutants were detected in six patients (15%). YMDD and adefovir-resistant mutants were detected in 57 and 35% of patients at baseline, respectively. At 48 weeks of therapy, 96 and 4% of patients had YMDD and adefovir-resistant mutants, respectively. These data suggest an early development of ETV resistance and low antiviral response during ETV therapy in adefovir-refractory patients with prior lamivudine resistance.
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Affiliation(s)
- S W Cho
- Department of Gastroeneterlogy, Ajou University School of Medicine, San-5 Wonchon-Dong, Yountong-Ku, Suwon, 442-821, South Korea.
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Gonzalez SA, Keeffe EB. Entecavir for the long-term treatment of chronic hepatitis B. Expert Rev Anti Infect Ther 2010; 7:1053-62. [PMID: 19883325 DOI: 10.1586/eri.09.75] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Hepatitis B virus is a major cause of chronic liver disease worldwide and is associated with an increased risk of hepatocellular carcinoma, progressive hepatic fibrosis and end-stage liver disease. Suppression of HBV replication is recognized as the primary on-treatment goal of antiviral therapy, as reduction of serum HBV DNA to low or undetectable levels is highly likely to have a positive impact on long-term clinical outcomes in HBV-associated chronic liver disease. Entecavir is an oral nucleoside analogue that effectively inhibits HBV polymerase, resulting in rapid viral suppression. Long-term data on patients receiving entecavir for chronic hepatitis B have demonstrated high potency, a low incidence of antiviral drug resistance and good tolerability, making entecavir an ideal first-line agent for the treatment of chronic hepatitis B.
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Affiliation(s)
- Stevan A Gonzalez
- Division of Hepatology, Baylor Regional Transplant Institute, Baylor All Saints Medical Center, 1400 8th Avenue, Building C, 1st Floor, Fort Worth, TX 76104, USA.
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Walsh AW, Langley DR, Colonno RJ, Tenney DJ. Mechanistic characterization and molecular modeling of hepatitis B virus polymerase resistance to entecavir. PLoS One 2010; 5:e9195. [PMID: 20169198 PMCID: PMC2820545 DOI: 10.1371/journal.pone.0009195] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2009] [Accepted: 01/06/2010] [Indexed: 01/25/2023] Open
Abstract
Background Entecavir (ETV) is a deoxyguanosine analog competitive inhibitor of hepatitis B virus (HBV) polymerase that exhibits delayed chain termination of HBV DNA. A high barrier to entecavir-resistance (ETVr) is observed clinically, likely due to its potency and a requirement for multiple resistance changes to overcome suppression. Changes in the HBV polymerase reverse-transcriptase (RT) domain involve lamivudine-resistance (LVDr) substitutions in the conserved YMDD motif (M204V/I ± L180M), plus an additional ETV-specific change at residues T184, S202 or M250. These substitutions surround the putative dNTP binding site or primer grip regions of the HBV RT. Methods/Principal Findings To determine the mechanistic basis for ETVr, wildtype, lamivudine-resistant (M204V, L180M) and ETVr HBVs were studied using in vitro RT enzyme and cell culture assays, as well as molecular modeling. Resistance substitutions significantly reduced ETV incorporation and chain termination in HBV DNA and increased the ETV-TP inhibition constant (Ki) for HBV RT. Resistant HBVs exhibited impaired replication in culture and reduced enzyme activity (kcat) in vitro. Molecular modeling of the HBV RT suggested that ETVr residue T184 was adjacent to and stabilized S202 within the LVDr YMDD loop. ETVr arose through steric changes at T184 or S202 or by disruption of hydrogen-bonding between the two, both of which repositioned the loop and reduced the ETV-triphosphate (ETV-TP) binding pocket. In contrast to T184 and S202 changes, ETVr at primer grip residue M250 was observed during RNA-directed DNA synthesis only. Experimentally, M250 changes also impacted the dNTP-binding site. Modeling suggested a novel mechanism for M250 resistance, whereby repositioning of the primer-template component of the dNTP-binding site shifted the ETV-TP binding pocket. No structural data are available to confirm the HBV RT modeling, however, results were consistent with phenotypic analysis of comprehensive substitutions of each ETVr position. Conclusions Altogether, ETVr occurred through exclusion of ETV-TP from the dNTP-binding site, through different, novel mechanisms that involved lamivudine-resistance, ETV-specific substitutions, and the primer-template.
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Affiliation(s)
- Ann W. Walsh
- Research and Development, Bristol-Myers Squibb Inc., Wallingford, Connecticut, United States of America
| | - David R. Langley
- Research and Development, Bristol-Myers Squibb Inc., Wallingford, Connecticut, United States of America
- * E-mail: (DRL); (DJT)
| | - Richard J. Colonno
- Research and Development, Bristol-Myers Squibb Inc., Wallingford, Connecticut, United States of America
| | - Daniel J. Tenney
- Research and Development, Bristol-Myers Squibb Inc., Wallingford, Connecticut, United States of America
- * E-mail: (DRL); (DJT)
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Zoulim F, Locarnini S. Hepatitis B virus resistance to nucleos(t)ide analogues. Gastroenterology 2009; 137:1593-608.e1-2. [PMID: 19737565 DOI: 10.1053/j.gastro.2009.08.063] [Citation(s) in RCA: 515] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2009] [Revised: 08/28/2009] [Accepted: 08/28/2009] [Indexed: 02/07/2023]
Abstract
Patients with chronic hepatitis B (CHB) can be successfully treated using nucleos(t)ide analogs (NA), but drug-resistant hepatitis B virus (HBV) mutants frequently arise, leading to treatment failure and progression to liver disease. There has been much research into the mechanisms of resistance to NA and selection of these mutants. Five NA have been approved by the US Food and Drug Administration for treatment of CHB; it is unlikely that any more NA will be developed in the near future, so it is important to better understand mechanisms of cross-resistance (when a mutation that mediates resistance to one NA also confers resistance to another) and design more effective therapeutic strategies for these 5 agents. The genes that encode the polymerase and envelope proteins of HBV overlap, so resistance mutations in polymerase usually affect the hepatitis B surface antigen; these alterations affect infectivity, vaccine efficacy, pathogenesis of liver disease, and transmission throughout the population. Associations between HBV genotype and resistance phenotype have allowed cross-resistance profiles to be determined for many commonly detected mutants, so genotyping assays can be used to adapt therapy. Patients that experience virologic breakthrough or partial response to their primary therapy can often be successfully treated with a second NA, if this drug is given at early stages of these events. However, best strategies for preventing NA resistance include first-line use of the most potent antivirals with a high barrier to resistance. It is important to continue basic research into HBV replication and pathogenic mechanisms to identify new therapeutic targets, develop novel antiviral agents, design combination therapies that prevent drug resistance, and decrease the incidence of complications of CHB.
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Kurashige N, Ohkawa K, Hiramatsu N, Yakushijin T, Mochizuki K, Oze T, Kiso S, Kanto T, Takehara T, Kasahara A, Doi Y, Yamada A, Fukuda K, Oshita M, Mita E, Fukui H, Nagase T, Yoshihara H, Imai Y, Kato M, Kashihara T, Hayashi N. Lamivudine-to-entecavir switching treatment in type B chronic hepatitis patients without evidence of lamivudine resistance. J Gastroenterol 2009; 44:864-70. [PMID: 19475333 DOI: 10.1007/s00535-009-0076-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2009] [Accepted: 04/15/2009] [Indexed: 02/04/2023]
Abstract
PURPOSE A considerable number of chronic hepatitis B (CH-B) patients remain under continuous lamivudine treatment, although switching treatment to entecavir could be beneficial. We investigated the antiviral efficacy of switching treatment to entecavir in CH-B patients without apparent evidence of lamivudine resistance during the preceding lamivudine treatment. METHODS Forty-four CH-B patients, who underwent lamivudine treatment for more than 6 months and showed no evidence of lamivudine resistance, switched to entecavir. Serial changes in hepatitis B virus (HBV) DNA were correlated with the patients' baseline HBV DNA at the commencement of entecavir administration. The entecavir-resistant substitution was examined by PCR-direct sequencing. The median follow-up period of entecavir treatment was 20 (10-23) months. RESULTS All 31 patients with baseline HBV DNA <2.6 logcopies/ml maintained HBV DNA-negative status during entecavir treatment. Of seven patients having HBV DNA of 2.6-<4.0 logcopies/ml, all achieved undetectable HBV DNA at the end of follow-up. As for six patients having HBV DNA >or=4.0 logcopies/ml, three patients achieved undetectable HBV DNA, whereas virological breakthrough was observed in one patient at month 15. An entecavir-resistant virus having rtM204V, rtL180M and rtS202G substitutions was detected in this patient. CONCLUSIONS The lamivudine-to-entecavir switching treatment may be generally recommendable in CH-B patients without evidence of lamivudine resistance during the preceding lamivudine treatment. However, great care should be taken with respect to the emergence of entecavir-resistance, especially in patients who do not respond well to the preceding lamivudine treatment.
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Affiliation(s)
- Nao Kurashige
- Department of Gastroenterology and Hepatology, Osaka University Graduate School of Medicine, Suita, Japan
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Li H, Yoo JC, Hong JH. Novel synthesis and anti-HIV activity of 4'-branched exomethylene carbocyclic nucleosides using a ring-closing metathesis of triene. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2009; 27:1238-49. [PMID: 19003569 DOI: 10.1080/15257770802458246] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The exomethylene of 6 was successfully constructed from the aldehyde 5 using Eschenmoser's reagents. A triene compound 7 was cyclized successfully using Grubbs' II catalyst to give an exomethylene carbocycle nucleus for the target compound. A Mitsunobu reaction was successfully used to condense the natural bases (adenine, thymine, uracil, and cytosine). The synthesized cytosine analogue 20 showed moderate anti-HIV activity (EC(50) = 10.67 microM).
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Affiliation(s)
- Hua Li
- BK-21 Project Team, College of Pharmacy, Chosun University, Kwangju, Republic of Korea
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Li JJ, Geng CX, Lv ZG. Therapeutic efficacy of entecavir in chronic HBV-infected patients: an analysis of 30 cases. Shijie Huaren Xiaohua Zazhi 2009; 17:425-428. [DOI: 10.11569/wcjd.v17.i4.425] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To explore the therapeutic efficacy of entecavir in chronic HBV-infected patients.
METHODS: A total of 30 chronic HBV-infected patients in our hospital were treated with 0.5mg per day. Levels of HBV DNA and ALT were measured before treatment and on 4, 12, 24 weeks after treatment. At the same time, hyaluronic acid (HA), laminin (LN), procollagen TypeⅢ (PCⅢ) and collagen typeⅣ (CⅣ) were also determined.
RESULTS: HBV DNA was decreased significantly after treatment for 4, 12, 24 weeks (F = 47.79, P < 0.05).The recovery rate of ALT was also improved. Seroconversion occurred to 3 cases of 18 patients with HBsAg(+). Significant differences were observed in the levels of LN and HA after treatment, with remarkable difference at 12 weeks and 24 weeks after treatment (F = 2.73, 2.79, both P < 0.05). CIV was decreased significantly after treatment for 24 weeks. (F = 3.03, P < 0.05). The level of PCⅢ was decreased, but the difference was not statistically different.
CONCLUSION: Entecavir can effectively inhibit the HBV replication, improve liver function, decrease the levels of LN, HA, PCⅢ, CⅣ, and alleviate liver fibrosis.
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Shouval D, Lai CL, Chang TT, Cheinquer H, Martin P, Carosi G, Han S, Kaymakoglu S, Tamez R, Yang J, Tenney D, Brett-Smith H. Relapse of hepatitis B in HBeAg-negative chronic hepatitis B patients who discontinued successful entecavir treatment: the case for continuous antiviral therapy. J Hepatol 2009; 50:289-95. [PMID: 19070393 DOI: 10.1016/j.jhep.2008.10.017] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Revised: 08/20/2008] [Accepted: 10/24/2008] [Indexed: 12/13/2022]
Abstract
BACKGROUND/AIMS To evaluate the off-treatment durability of response in HBeAg-negative chronic hepatitis B patients who achieved a protocol-defined 'Response' (HBV-DNA<0.7MEq/mL and ALT<1.25xULN) with entecavir at 48 weeks and the efficacy of entecavir in patients treated beyond one year. METHODS Entecavir-treated and lamivudine-treated patients who achieved a protocol-defined 'Response' were evaluated off-treatment for HBV-DNA<300copies/mL and ALT normalisation. Entecavir- and lamivudine-treated patients who achieved a protocol-defined 'Virological Response' (HBV-DNA<0.7MEq/mL but ALT1.25xULN) at 48 weeks, continued blinded treatment until they achieved Response or 96 weeks, whichever came first. RESULTS Among 'Responders' who discontinued treatment after 48 weeks, 7/257 (3%) entecavir-treated and 10/201 (5%) lamivudine-treated patients sustained HBV-DNA below 300copies/mL at 24-weeks off-treatment. Among the 54 patients who continued blinded treatment in the second year, 7/26 (27%) entecavir-treated and 6/28 (21%) lamivudine-treated patients normalised ALT and 22/26 (85%) entecavir-treated and 16/28 (57%) lamivudine-treated patients maintained HBV-DNA<300copies/mL at end-of-dosing. The safety profiles of both drugs remained comparable through a second year of treatment. CONCLUSIONS The majority of protocol-defined Responders relapsed after 1 year when treatment was discontinued. Treatment with entecavir beyond 1 year provided continued virological and biochemical benefit.
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Affiliation(s)
- Daniel Shouval
- Liver Unit, Hadassah - Hebrew University Hospital, Ein-Kerem, Jerusalem 91120, Israel.
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