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Seto WK, Tanaka Y, Wong DKH, Shinkai N, Cheung KS, Liu KSH, Fung J, Lai CL, Yuen MF. Longitudinal profiles of highly sensitive hepatitis B surface antigen levels: re-evaluation of HBsAg seroclearance. Liver Int 2016; 36:642-50. [PMID: 26474013 DOI: 10.1111/liv.12980] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 08/18/2015] [Accepted: 09/30/2015] [Indexed: 02/13/2023]
Abstract
BACKGROUND & AIMS Serologic profiles after hepatitis B surface antigen (HBsAg) seroclearance in chronic hepatitis B (CHB) have not been well-studied. METHODS We employed a highly sensitive HBsAg (hs-HBsAg) assay (lower detection limit 0.5 mIU/ml), 100 times more sensitive than conventional HBsAg measurements. CHB patients achieving HBsAg seroclearance defined by conventional assays were followed up for serum hs-HBsAg, HBV DNA and antibody to HBsAg (anti-HBs) levels at 0 months, 6-12 months and 3-5 years after HBsAg seroclearance. Factors associated with hs-HBsAg detectability were determined. RESULTS One hundred and nine patients were recruited; 94 (86.2%) were followed up to years 3-5; and 25 patients (22.9%) were on nucleoside analogue therapy for a median duration of 6.0 (range 1.5-12.7) years before HBsAg seroclearance. Detectable hs-HBsAg was noted in 88 (80.7%), 60 (55.0%) and 20 (21.3%) patients at 0 months, 6-12 months and 3-5 years respectively. At years 3-5, genotype B patients, when compared to genotype C patients, had a higher anti-HBs positive rate (63.2% and 41.1% respectively, P = 0.036). Serum anti-HBs positivity, when compared to persistent anti-HBs negativity, was associated with a lower rate of hs-HBsAg detection (7.4% and 40% respectively, P < 0.001). Multivariate analysis showed anti-HBs negativity at years 3-5 to be independently associated with persistently positive hs-HBsAg (P = 0.007, odds ratio 7.1, 95% confidence interval 1.7-29.3). CONCLUSION Serum hs-HBsAg could detect HBsAg presence in a substantial proportion of CHB after HBsAg seroclearance defined by conventional assays, especially among anti-HBs negative individuals. Serum hs-HBsAg could potentially assist differentiating HBsAg-negative CHB from individuals with only past HBV exposure without carrier state.
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Affiliation(s)
- Wai-Kay Seto
- Department of Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, Hong Kong.,State Key Laboratory for Liver Research, Queen Mary Hospital, University of Hong Kong, Hong Kong, Hong Kong
| | - Yasuhito Tanaka
- Department of Virology and Liver Unit, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Danny K-H Wong
- Department of Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, Hong Kong.,State Key Laboratory for Liver Research, Queen Mary Hospital, University of Hong Kong, Hong Kong, Hong Kong
| | - Noboru Shinkai
- Department of Virology and Liver Unit, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Ka-Shing Cheung
- Department of Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, Hong Kong
| | - Kevin S-H Liu
- Department of Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, Hong Kong
| | - James Fung
- Department of Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, Hong Kong.,State Key Laboratory for Liver Research, Queen Mary Hospital, University of Hong Kong, Hong Kong, Hong Kong
| | - Ching-Lung Lai
- Department of Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, Hong Kong.,State Key Laboratory for Liver Research, Queen Mary Hospital, University of Hong Kong, Hong Kong, Hong Kong
| | - Man-Fung Yuen
- Department of Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, Hong Kong.,State Key Laboratory for Liver Research, Queen Mary Hospital, University of Hong Kong, Hong Kong, Hong Kong
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Seto WK, Liu K, Wong DKH, Fung J, Huang FY, Hung IFN, Lai CL, Yuen MF. Patterns of hepatitis B surface antigen decline and HBV DNA suppression in Asian treatment-experienced chronic hepatitis B patients after three years of tenofovir treatment. J Hepatol 2013; 59:709-16. [PMID: 23792029 DOI: 10.1016/j.jhep.2013.06.007] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Revised: 05/30/2013] [Accepted: 06/11/2013] [Indexed: 12/11/2022]
Abstract
BACKGROUND & AIMS Patterns of serum hepatitis B surface antigen (HBsAg) decline during nucleos(t)ide analogue (NA) therapy have not been well investigated. METHODS We determined the cumulative serologic, virologic, and biochemical outcomes of 142 Asian CHB patients, with at least 6 months exposure to other NAs, receiving tenofovir with or without lamivudine for up to 3 years. Liver biochemistry, serum HBV DNA, and HBsAg levels were determined at baseline, 6 months and yearly from years 1 to 3. RESULTS 142, 123 (86.6%), and 70 (49.3%) CHB patients were followed up for 1, 2, and 3 years, respectively. Two phases of HBsAg decline were observed. Patients with baseline HBsAg ≥3 log IU/ml, when compared to patients with baseline HBsAg < 3 log IU/ml, had a greater median rate of HBsAg reduction through 3 years of treatment (0.155 and 0.039 log IU/ml/year respectively, p < 0.001). Among patients with 3 years of follow-up, there was a significantly greater median rate of HBsAg reduction during the first year when compared to the second and third years (0.220, 0.136, and 0.081 log IU/ml/year respectively, p < 0.001). HBeAg status, HBV genotype, and concomitant lamivudine therapy were not important determinants of HBsAg kinetics (all p > 0.05). The 3-year cumulative virologic suppression rate was 93.3%, with no cases of resistance detected. CONCLUSIONS Serum HBsAg levels in NA-experienced patients receiving tenofovir demonstrated a variable pattern of decline, with slower rates of reduction noted in patients with lower baseline HBsAg levels, and could explain the rarity of HBsAg seroclearance during NA therapy.
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Affiliation(s)
- Wai-Kay Seto
- Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong
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3
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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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Lam YF, Yuen MF, Seto WK, Lai CL. Current Antiviral Therapy of Chronic Hepatitis B: Efficacy and Safety. CURRENT HEPATITIS REPORTS 2011; 10:235-243. [PMID: 22131901 PMCID: PMC3210946 DOI: 10.1007/s11901-011-0109-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The treatment of chronic hepatitis B is in constant evolution. Interferon, the first agent licensed for chronic hepatitis B treatment, has been superseded by the growing popularity of nucleoside/nucleotide analogues (NA). However, resistance to these agents is a major challenge. Newer NAs, such as entecavir and tenofovir dipivoxil fumarate, have very low resistance rates and favorable safety profiles. Long-term use of these agents can effectively suppress hepatitis B virus DNA, leading to decrease in incidence of hepatitic flares, as well as in the development of cirrhosis and hepatocellular carcinoma. The efficacy and safety of various antiviral agents is discussed in this review.
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Affiliation(s)
- Yuk-Fai Lam
- Department of Medicine, The University of Hong Kong Queen Mary Hospital, Pokfulam Road, Hong Kong, Hong Kong
| | - Man-Fung Yuen
- Department of Medicine, The University of Hong Kong Queen Mary Hospital, Pokfulam Road, Hong Kong, Hong Kong
| | - Wai-Kay Seto
- Department of Medicine, The University of Hong Kong Queen Mary Hospital, Pokfulam Road, Hong Kong, Hong Kong
| | - Ching-Lung Lai
- Department of Medicine, The University of Hong Kong Queen Mary Hospital, Pokfulam Road, Hong Kong, Hong Kong
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5
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Fung J, Lai CL, Seto WK, Yuen MF. Nucleoside/nucleotide analogues in the treatment of chronic hepatitis B. J Antimicrob Chemother 2011; 66:2715-25. [PMID: 21965435 DOI: 10.1093/jac/dkr388] [Citation(s) in RCA: 130] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The current available agents for the treatment of chronic hepatitis B (CHB) include immunomodulatory agents, such as interferon-α and pegylated interferon-α, and oral nucleoside/nucleotide analogues (NAs), including lamivudine, adefovir, telbivudine, entecavir and tenofovir. The NAs work mainly by inhibiting hepatitis B virus (HBV) DNA polymerase activity and thus suppress HBV replication. Oral NAs have become the mainstay of CHB treatment, mainly due to their profound viral suppressive effects and also due in part to the ease of single daily dosing and lack of significant side effects. One major drawback of NA therapy is the development of drug resistance mutations with long-term treatment. Lamivudine, the first oral NA approved for CHB patients, is associated with high rates of drug resistance, with resultant virological relapse and biochemical flare. Fortunately, newer and more potent NAs, such as entecavir and tenofovir, have very low resistance rates, with potent and durable viral suppression. This review is aimed at the current developments in NAs for CHB treatment, detailing the mechanisms of antiviral activity of the different agents, the efficacy of viral suppression, the achievement of treatment endpoints, the development of drug resistance and the optimal strategies for using these drugs.
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Affiliation(s)
- James Fung
- Department of Medicine, University of Hong Kong, Queen Mary Hospital, Hong Kong SAR
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Ding X, Yang J, Wang S. Antisense Oligonucleotides Targeting Abhydrolase Domain Containing 2 Block Human Hepatitis B Virus Propagation. Oligonucleotides 2011; 21:77-84. [DOI: 10.1089/oli.2011.0280] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Xiaoran Ding
- Beijing Institute of Radiation Medicine, Beijing, People's Republic of China
| | - Jing Yang
- Beijing Institute of Radiation Medicine, Beijing, People's Republic of China
| | - Shengqi Wang
- Beijing Institute of Radiation Medicine, Beijing, People's Republic of China
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Antiviral treatment of chronic hepatitis B virus (HBV) infections. Viruses 2010; 2:1279-1305. [PMID: 21994680 PMCID: PMC3185710 DOI: 10.3390/v2061279] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2010] [Revised: 05/18/2010] [Accepted: 05/25/2010] [Indexed: 12/21/2022] Open
Abstract
While 25 compounds have been formally licensed for the treatment of HIV infection (AIDS), only seven licensed products are currently available for the treatment of chronic hepatitis B virus (HBV) infection: interferon-α, pegylated interferon-α, lamivudine, adefovir (dipivoxil), entecavir, telbivudine and tenofovir (disoproxil fumarate). In contrast to the treatment of HIV infections where the individual drugs are routinely used in combination, for the treatment of chronic HBV infection the individual drugs are generally used in monotherapy. In principle, combination drug therapy should allow reducing the likelihood of drug-resistant development.
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Férir G, Kaptein S, Neyts J, De Clercq E. Antiviral treatment of chronic hepatitis B virus infections: the past, the present and the future. Rev Med Virol 2008; 18:19-34. [PMID: 17966115 DOI: 10.1002/rmv.554] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
A decade ago, standard therapy against chronic hepatitis B virus infections only consisted of lamivudine or IFN-alpha. Treatment with lamivudine and IFN has been compounded by, respectively, the emergence of drug-resistant virus strains and the appearance of serious side effects. In the last 10 years, hepatitis B treatment has made much progress. Several treatments are now licensed for the treatment of patients with chronic hepatitis B and others are under development. Here, we provide an overview of the potential and mode of action of anti-HBV agents that are currently available, and/or may become available in the near future. Foremost among these newer compounds are adefovir dipivoxil, entecavir and telbivudine.
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Affiliation(s)
- Geoffrey Férir
- Rega Institute for Medical Research, KULeuven, Leuven, Belgium
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Piratvisuth T, Lau G, Chao YC, Jin R, Chutaputti A, Zhang QB, Tanwandee T, Button P, Popescu M. Sustained response to peginterferon alfa-2a (40 kD) with or without lamivudine in Asian patients with HBeAg-positive and HBeAg-negative chronic hepatitis B. Hepatol Int 2008; 2:102-10. [PMID: 19669285 PMCID: PMC2716864 DOI: 10.1007/s12072-007-9022-5] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2007] [Revised: 08/05/2007] [Accepted: 08/07/2007] [Indexed: 12/21/2022]
Abstract
PURPOSE The 2 reported trials investigated the effectiveness of treatment with peginterferon alfa-2a in Asian patients with chronic hepatitis B (CHB). METHODS Patients with HBeAg-positive (n = 708) or HBeAg-negative (n = 332) CHB were enrolled in 2 randomized, double blind, placebo-controlled studies. Patients received peginterferon alfa-2a 180 mug once weekly, peginterferon plus lamivudine 100 mg per day, or lamivudine alone for 48 weeks. Patients were followed up at 6 and 12 months posttreatment. RESULTS Peginterferon alfa-2a provided significantly higher rates of HBeAg seroconversion (31%) in HBeAg-positive patients than did lamivudine (19%, P = 0.005) 6 months posttreatment, irrespective of genotype. Of these, 83% achieving seroconversion during treatment or early posttreatment sustained their response at 12 months posttreatment. In patients who seroconverted, 69% maintained HBV DNA suppression at <10,000 copies/ml and alanine aminotrasferase (ALT) normalization. In HBeAg-negative patients, peginterferon produced a significantly higher combined response of HBV DNA at <20,000 copies/ml and ALT normalization (45%) than lamivudine (31%, P = 0.032), irrespective of genotype. Almost 80% of these patients sustained their response at 12 months posttreatment. CONCLUSIONS In conclusion, a finite course of peginterferon alfa-2a provides significant and sustained treatment benefit in Asian CHB patients, who have traditionally been regarded as difficult to treat.
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Affiliation(s)
- Teerha Piratvisuth
- Department of Internal Medicine, NKC Institute of Gastroenterology and Hepatology, Songklanagarind Hospital , Prince of Songkla University, Hat Yai, Songkla, 90110, Thailand,
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Sucupira MVF, Mello FCA, Santos EA, Niel C, Rolla VC, Arabe J, Gomes SA. Patterns of hepatitis B virus infection in Brazilian human immunodeficiency virus infected patients: high prevalence of occult infection and low frequency of lamivudine resistant mutations. Mem Inst Oswaldo Cruz 2007; 101:655-60. [PMID: 17072479 DOI: 10.1590/s0074-02762006000600013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2006] [Accepted: 07/05/2006] [Indexed: 01/15/2023] Open
Abstract
Hepatitis B virus (HBV) molecular profiles were determined for 44 patients who were infected with human immunodeficiency virus (HIV) type 1 and had antibodies to the hepatitis B core antigen (anti-HBc), with and without other HBV serological markers. In this population, 70% of the patients were under lamivudine treatment as a component of antiretroviral therapy. HBV DNA was detected in 14 (32%) patients. Eight out of 12 (67%) HBsAg positive samples, 3/10 (30%) anti-HBc only samples, and 3/22 (14%) anti-HBs positive samples were HBV DNA positive. HBV DNA loads, measured by real time polymerase chain reaction, were much higher in the HBsAg positive patients (mean, 2.5 x 10(9) copies/ml) than in the negative ones (HBV occult infection; mean, 2.7 x 10(5) copies/ml). Nine out of the 14 HBV DNA positive patients were under lamivudine treatment. Lamivudine resistant mutations in the polymerase gene were detected in only three patients, all of them belonging to the subgroup of five HBsAg positive, HBV DNA positive patients. A low mean HBV load (2.7 x 10(5) copies/ml) and an absence of lamivudine resistant mutations were observed among the cases of HBV occult infection.
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Affiliation(s)
- Michel V F Sucupira
- Departamento de Virologia, Instituto Oswaldo Cruz, Av. Brasil 4365, 21040-900 Rio de Janeiro, RJ, Brazil
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Bozkaya H, Yurdaydin C, Idilman R, Tüzün A, Cinar K, Erkan Ö, Bozdayi AM, Erden E, Uzun Y, Cetinkaya H, Uzunalimoglu Ö. Lamivudine Treatment in Hbeag-Negative Chronic Hepatitis B Patients with Low Level Viraemia. Antivir Ther 2005. [DOI: 10.1177/135965350501000214] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Background Our aim was to determine the short-term natural course of viraemia and the response to lamivudine treatment in HBeAg-negative chronic hepatitis B patients with a persistently low hepatitis B virus (HBV)-DNA level. Methods A total of 55 patients were included. Group 1 consisted of 37 patients with low-level viraemia and high serum alanine aminotransferase (ALT) levels and further randomized to two groups: group 1a ( n=19) patients received 1 year of lamivudine therapy and group 1b ( n=18) patients were untreated controls. Group 2 consisted of 18 inactive carriers who were followed as controls of untreated low viraemic chronic hepatitis B patients. HBV DNA was longitudinally determined by real-time polymerase chain reaction assay. Results A female predominance in group 2 was observed while males were predominant in group 1. Mean age and baseline HBV-DNA levels did not differ between group 1 and 2 patients while group 1 patients had a higher histological score ( P<0.01). Of group 1a patients, 44% had complete ALT normalization at end of treatment, whereas 21% untreated group 1b patients had normal ALT at the end of the follow-up. No change in histological activity was observed in group 1a patients at the end of treatment. HBV-DNA levels did not significantly change from baseline to end-of-treatment/observation period in patient groups. The viraemia course was not different across the groups. Conclusions Low viraemic HBeAg-negative patients with high ALT present with minimal/mild histological activity. Inactive carriers cannot be differentiated from low viraemic patients with high ALT based on HBV DNA determination. Although lamivudine treatment can be effective in some cases, observation rather than a prompt treatment attempt seems to be more logical because of mild histological changes and low response rate to treatment in these patients.
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Affiliation(s)
- Hakan Bozkaya
- Department of Gastroenterology, Ankara University School of Medicine, Cebeci, Ankara-Turkey
- Ankara University Hepatology Institute, Cebeci, Ankara-Turkey
| | - Cihan Yurdaydin
- Department of Gastroenterology, Ankara University School of Medicine, Cebeci, Ankara-Turkey
- Ankara University Hepatology Institute, Cebeci, Ankara-Turkey
| | - Ramazan Idilman
- Department of Gastroenterology, Ankara University School of Medicine, Cebeci, Ankara-Turkey
| | - Ali Tüzün
- Department of Gastroenterology, Ankara University School of Medicine, Cebeci, Ankara-Turkey
| | - Kubilay Cinar
- Department of Gastroenterology, Ankara University School of Medicine, Cebeci, Ankara-Turkey
| | - Özlem Erkan
- Ankara University Hepatology Institute, Cebeci, Ankara-Turkey
| | - A Mithat Bozdayi
- Department of Gastroenterology, Ankara University School of Medicine, Cebeci, Ankara-Turkey
- Ankara University Hepatology Institute, Cebeci, Ankara-Turkey
| | - Esra Erden
- Department of Pathology, Ankara University School of Medicine, Sihhiye, Ankara-Turkey
| | - Yusuf Uzun
- Department of Gastroenterology, Blacksea Technical University, Trabzon, Turkey
| | - Hülya Cetinkaya
- Department of Gastroenterology, Ankara University School of Medicine, Cebeci, Ankara-Turkey
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Torre F, Mattioli F, Campo N, Delfino A, Basso M, Pelli N, Martelli A, Picciotto A. Serum lamivudine levels in the presence of a lamivudine-resistant HBV mutant. Dig Liver Dis 2004; 36:677-81. [PMID: 15506667 DOI: 10.1016/j.dld.2004.03.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND/AIMS Lamivudine efficiently inhibits hepatitis B virus replication and has been used to treat hepatitis B virus recurrence after orthotopic liver transplantation. Although effective, its use is hampered by viral breakthrough due to the appearance of hepatitis B virus drug-resistant strains. Aims of this work were to evaluate the inter- and intra-individual variations of lamivudine serum levels and the effects on the drug levels of the lamivudine-resistant hepatitis B virus mutant infection. METHODS Serum lamivudine concentration was measured by high-performance liquid chromatography. Polymerase chain reaction analysis and sequencing analysis of the reverse transcriptase area of the polymerase was performed on each sample using specific primers. A polymerase chain reaction-enzyme-linked immunosorbent assay was used to differentiate between wild-type hepatitis B virus and lamivudine-resistant hepatitis B virus strain. RESULTS Lamivudine serum levels presented minor inter- and intra-individual fluctuations along time, with an important increase at the time of the hepatitis flare-up due to the hepatitis B virus mutant presence. When the wild-type hepatitis B virus briefly reappeared as a mixed population, the titre of lamivudine dropped to below the detection level. CONCLUSIONS While lamivudine serum levels appears stable when the anti-viral efficacy is fully achieved, important fluctuations are present according to the type of viral population, with a considerable decrease possibly due to the presence of the wild-type virus.
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Affiliation(s)
- F Torre
- Department of Internal Medicine, University of Genoa, Viale Benedetto XV, 6, 16132, Genoa, Italy
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Yekeler H. Preferred conformations of some pyrimidine nucleoside reverse transcriptase inhibitors (NRTIs). ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.theochem.2004.06.036] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Santos EA, Sucupira MVF, Arabe J, Gomes SA. Hepatitis B virus variants in an HIV-HBV co-infected patient at different periods of antiretroviral treatment with and without lamivudine. BMC Infect Dis 2004; 4:29. [PMID: 15339340 PMCID: PMC516776 DOI: 10.1186/1471-2334-4-29] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2004] [Accepted: 08/31/2004] [Indexed: 02/07/2023] Open
Abstract
Background Lamivudine inhibits replication of both human immunodeficiency virus (HIV) and hepatitis B virus (HBV) and is commonly used as part of antiretroviral therapy. The main limitation in the use of lamivudine is resistant mutation selection. Most of these mutations affect the YMDD motif of the HBV DNA polymerase. The resistance occurs through M550V or M550I aminoacid replacements. The M550V variation may be accompanied by L526M mutation, notably in HIV-HBV co-infected patients. The aim of this study was to investigate mutations associated with lamivudine resistance in a hemodialysis patient chronically co-infected with HIV-1 and HBV, who was submitted to several antiretroviral treatments. Methods HBV isolates derived from three blood samples collected at different times of antiretroviral therapies with and without lamivudine, were titred and submitted to nucleotide sequencing. Results HBV isolate derived from a sample collected in 1999 during an antiretroviral treatment with lamivudine showed the lamivudine resistant double mutation (L526M, M550V). However, no mutation associated with lamivudine resistance was observed in the HBV genome derived from the sample collected during a period of treatment without lamivudine (2001). After reinstitution of lamivudine (2002), the predominant HBV population exhibited a rare triple mutation (V519L, L526M, M550V), which has previously been associated with an in vitro reduction of virus antigenicity (escape mutant). HBV DNA was detected at high levels (108–109 copies/ml) in the three blood samples. Conclusions Reintroduction of lamivudine as part of antiretroviral treatment in a patient who had developed lamivudine resistant HBV strains favored the predominance of an HBV isolate with reduced antigenicity. The absence of hepatitis acute exacerbation in this patient may be correlated to the absence of significant variations of the viral load, which was independent of the presence of mutations in the HBV DNA polymerase.
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Affiliation(s)
- Eneida A Santos
- Department of Virology, Oswaldo Cruz Institute, Rio de Janeiro, RJ 21045-900, Brazil
| | - Michel VF Sucupira
- Department of Virology, Oswaldo Cruz Institute, Rio de Janeiro, RJ 21045-900, Brazil
| | - Juçara Arabe
- Gaffrée and Guinle University Hospital, Rio de Janeiro, RJ 20270-004, Brazil
| | - Selma A Gomes
- Department of Virology, Oswaldo Cruz Institute, Rio de Janeiro, RJ 21045-900, Brazil
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Hacker HJ, Zhang W, Tokus M, Bock T, Schröder CH. Patterns of circulating hepatitis B virus serum nucleic acids during lamivudine therapy. Ann N Y Acad Sci 2004; 1022:271-81. [PMID: 15251972 DOI: 10.1196/annals.1318.042] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Lamivudine treatment of individuals with chronic HBV infection leads to a rapid decline of hepatitis B virus (HBV) serum DNA. Because HBV replication quickly reaches pretreatment values following cessation of the drug, we addressed the question of whether changes during therapy in composition and amount of discernible circulating viral DNA and RNA might provide an explanation for this phenomenon. Nucleic acids were extracted from serial serum samples of two chronically infected patients. The first patient was treated with lamivudine for 14 weeks, whereas the second one, who displayed an HBV virus with a core gene mutation, received lamivudine for 10 weeks. Three sequence segments of the HBV genome synthesized successively during replication, namely, X, C, and X-preC, were analyzed via competitive polymerase chain reaction (PCR) and reverse transcriptase (RT)/PCR. HBV transcripts were also analyzed for differential polyadenylation. At the start of treatment, identical DNA copy numbers (10(9)/mL) were found for all three segments in the first patient. C segment DNA displayed the expected rapid decline. X-preC, a target contiguous only on plus-strand DNA, behaved similarly. In contrast, the X segment DNA copy numbers showed a less pronounced decrease, remaining at higher values (10(7)/mL) than the C and X-preC segments (both about 2 x 10(5)/mL) at the end of therapy. X segment RNA displayed a persisting copy number of about 10(7)/mL, whereas C and X-preC RNA decreased to about 10(5) copies/mL. Polyadenylated HBV RNA, both full-length and truncated, initially persisted at 10(5) but decreased to 10(4) to 10(3) copies/mL at the end of treatment. As expected, C segment DNA and RNA were not detected in the second patient, whereas X and X-preC segments showed essentially the same pattern as the first patient, although at a slightly lower level. We conclude that: (1) actual numbers of HBV genome equivalents during lamivudine therapy can be assessed only via X segment DNA, because it is reverse transcribed first; (2) lamivudine induces coexistence of DNA and RNA for the C and X segments at similar levels, indicating drug-arrested intermediates of reverse-transcribed HBV DNA minus-strand; and (3) packaged HBV RNA lacks a poly(A) tail, whereas polyadenylated RNA is likely not packaged.
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Affiliation(s)
- Hans Jörg Hacker
- Department of Virus-Host Interactions, Deutsches Krebsforschungszentrum, Heidelberg, Germany.
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Sablon E, Shapiro F, Zoulim F. Early detection of hepatitis B drug resistance: implications for patient management. Expert Rev Mol Diagn 2004; 3:535-47. [PMID: 14510175 DOI: 10.1586/14737159.3.5.535] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Despite the availability of safe and effective prophylactic vaccines, hepatitis B viral disease has remained a tenacious scourge, ranking ninth globally among all causes of mortality (up to 1 million deaths annually). Approximately 6% of the global population--more than 350 million people--have failed to resolve viral infection and become chronic carriers, eventually placing between 15 and 25% of such individuals at risk for end-stage liver disease. Until recently, the immunomodulator interferon-alpha and especially the nucleoside analog lamivudine (Epivir) have been the treatments of choice for chronic hepatitis B viral infection. However, the inexorable development of drug resistance to lamivudine has been a major clinical impediment to the long-term use of such treatment. Herein, the current and future diagnostic methods for early detection of emerging drug resistance to the hepatitis B virus is reviewed. Given the recent approval of adefovir dipivoxil (Hepsera) and the possibility that other nucleoside and nucleotide analogs could soon become part of the hepatitis B virus therapeutic arsenal, the clinical ramifications for co-ordinated use of diagnostic tests together with new antihepadenaviral agents for optimal patient management is also discussed.
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Affiliation(s)
- Erwin Sablon
- Hepatology Unit, Theranostics R&D, Innogenetics NV, Industriepark Zwijnaarde 7/4, B-9052 Gent, Belgium.
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17
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Affiliation(s)
- Claire Thomas
- Chelsea and Westminster Hospital, 369 Fulham Road London, United Kingdom
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18
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Yuen MF, Kato T, Mizokami M, Chan AOO, Yuen JCH, Yuan HJ, Wong DKH, Sum SM, Ng IOL, Fan ST, Lai CL. Clinical outcome and virologic profiles of severe hepatitis B exacerbation due to YMDD mutations. J Hepatol 2003; 39:850-5. [PMID: 14568270 DOI: 10.1016/s0168-8278(03)00388-x] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND/AIMS To study the outcome and the virologic profiles of severe hepatitis exacerbations due to YMDD mutants in lamivudine-treated patients. METHODS Eighteen lamivudine-treated patients with severe hepatitis exacerbations due to YMDD mutants were recruited. Laboratory and clinical parameters were monitored. Viral genotypes and YMDD mutations were determined. RESULTS None of the 18 patients had YMDD wild-type during exacerbations. Three (17%) and 15 (83%) patients had genotypes B and C, respectively. Elevated bilirubin levels and prolonged prothrombin time were found in 11 (61%) and six patients (33%) respectively. Three patients (17%) had adverse outcome with the development of ascites and/or encephalopathy. One of these patients required liver transplantation and one died. Both patients had evidence of cirrhosis before treatment and hepatitis B e antigen (HBeAg) seroreversion from anti-HBe positivity. The remaining 16 patients (89%) have no evidence of pre-existing cirrhosis. Thirty seven percent of patients had normal alanine aminotransferase levels at the last follow-up. The median HBV DNA level at the last follow-up was significantly lower than the pre-treatment level (P=0.009). CONCLUSIONS Though the majority of patients with severe hepatitis exacerbations due to YMDD mutants had uneventful course, early liver transplantation should be considered in patients with pre-existing cirrhosis and HBeAg seroreversion.
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Affiliation(s)
- Man-Fung Yuen
- Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Pokfulam Road, Hong Kong, PR, China
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19
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Zhang W, Hacker HJ, Tokus M, Bock T, Schröder CH. Patterns of circulating hepatitis B virus serum nucleic acids during lamivudine therapy. J Med Virol 2003; 71:24-30. [PMID: 12858405 DOI: 10.1002/jmv.10464] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
We examined whether lamivudine treatment, in addition to the rapid decline of HBV serum DNA described in a large number of laboratories, causes changes in composition and amount of discernable circulating viral DNA and RNA. Nucleic acids were extracted from serial serum samples of a patient infected chronically and treated with lamivudine for 14 weeks. Three sequence segments of the HBV genome synthesized successively during replication, X, C, and X-preC, were analyzed by competitive PCR and RT/PCR. In addition, RNA was examined for differential polyadenylation. Before treatment, identical DNA copy numbers (10(9)/ml) were found in all three segments. C segment DNA displayed the expected rapid decline. X-preC, a target contiguous only on plus-strand DNA behaved similarly. In contrast, the X segment DNA copy numbers showed a less pronounced decrease remaining at higher values (10(7)/ml) than the C and X-preC segment (both about 2 x 10(5)/ml) at the end of therapy. X segment RNA displayed a persisting copy number of about 10(7)/ml, while C and X-preC RNA decreased to about 10(5) copies/ml. Polyadenylated HBV RNA, full-length and truncated, persisted initially at 10(5) but decreased to 10(4) to 10(3) copies/ml at the end of treatment. The major conclusions are the actual numbers of virus particles during lamivudine therapy can only be assessed via X segment DNA, since it is reverse transcribed first, and Lamivudine induced coexistence of DNA and RNA for the C and X segment at similar levels indicates drug-arrested intermediates of reverse transcribed HBV DNA minus-strand. Packaged RNA lacks a poly(A) tail whereas polyadenylated RNA is likely not packaged.
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Affiliation(s)
- Wei Zhang
- Department of Virus-Host Interactions, Deutsches Krebsforschungszentrum Heidelberg, Germany
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20
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Wu JM, Lin JS, Xie N, Liang KH. Inhibition of hepatitis B virus by a novel L-nucleoside, β-L-D4A and related analogues. World J Gastroenterol 2003; 9:1840-3. [PMID: 12918134 PMCID: PMC4611557 DOI: 10.3748/wjg.v9.i8.1840] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To explore the inhibition of β-L-D4A on hepatitis B virus (HBV) in 2.2.15 cells derived from HepG2 cells transfected with HBV genome.
METHODS: 2.2.15 cells were plated at a density of 5 × 104 per well in 12-well tissue culture plates, and treated with various concentrations of β-L-D4A for 6 days. In the end, 5 μl of medium was used for the estimation of HBsAg and HBeAg, the other medium was processed to obtain virions by a polyethlene glycol precipitation method. At the same time, intracellular DNA was also extracted and digested with HindIII. Both DNAs were subjected to Southern blot, hybridized with a 32P-labeled HBV probe and autoradiographed. Intensity of the autoradiographic bands was quantitated by densitometric scans of computer and ED50 was calculated. Then Hybond-N membrane was washed and rehybridized with a 32P-labeled mtDNA-specific probe, and effect of β-L-D4A on mitochondrial DNA was studied. 2. 2.15 cells were also seeded in 24-well tissue culture plates, and cytotoxicity with different concentrations was examined by MTT method. ID50 was calculated. Structure-activity relationships between D2A and D4A were also studied as above.
RESULTS: Autoradiographic bands were similar between supernatant and intracellular HBV DNA. Episomal HBV DNA was inhibited in a dose-dependent manner. ED50 was 0.2 μM. HBsAg or HBeAg was not apparently decreased, and inhibition of mitochondrial DNA was not obvious. The experiment of cytotoxicity gained ID50 at 200 μM.
CONCLUSION: β-L-D4A possesses potent inhibitory effects on the replication of HBV in vitro with little cytotoxicity and mitochondrial toxicity, TI value is 1000. It is expected to be developed as a new clinically anti-HBV drug.
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Affiliation(s)
- Jin-Ming Wu
- Institute of Liver Diseases, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
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21
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Santos EA, Yoshida CFT, Rolla VC, Mendes JM, Vieira IF, Arabe J, Gomes SA. Frequent occult hepatitis B virus infection in patients infected with human immunodeficiency virus type 1. Eur J Clin Microbiol Infect Dis 2003; 22:92-8. [PMID: 12627282 DOI: 10.1007/s10096-002-0868-0] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The presence of hepatitis B virus (HBV) serological markers was investigated in 170 patients (137 male, 33 female) infected with human immunodeficiency virus (HIV) type 1. Antibodies to the hepatitis B core antigen (anti-HBc antibodies) were detected in 115 (68%) patients. Of these 115, 14 (12%) were hepatitis B surface antigen (HBsAg) positive, 60 (52%) presented anti-HBs antibodies, and 41 (35%) were anti-HBc positive only. All 115 of the anti-HBc positive samples were tested for HBV DNA by using two polymerase chain reaction (PCR) assays that amplify the core and pre-S regions of the HBV genome, respectively. HBV DNA was detected in 23 samples: 7 of 14 (50%) HBsAg-positive samples, 12 of 60 (20%) anti-HBs-positive samples, and 4 of 41 (10%) samples positive for anti-HBc only. Six samples (all HBsAg positive) were positive in both PCR assays and 17 samples were HBV DNA positive in only one assay. The mean viral load in HBsAg-positive patients was higher than that observed in HBsAg-negative patients. A number of patients were receiving treatment with lamivudine, a drug that interferes with both HBV and HIV replication. However, neither the rate of HBV DNA positivity nor HBV load was significantly different between patients treated with lamivudine and those not treated with this drug.
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Affiliation(s)
- E A Santos
- Departamento de Virologia, Instituto Oswaldo Cruz, Fiocruz, Av. Brasil 4365, 21045-900, Rio de Janeiro, RJ, Brazil
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22
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Macchi B, Mastino A. Pharmacological and biological aspects of basic research on nucleoside-based reverse transcriptase inhibitors. Pharmacol Res 2002; 46:473-82. [PMID: 12457619 DOI: 10.1016/s1043661802002128] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Antiretrovirals have progressively entered clinical practice since the discovery of the association between the acquired immunodeficiency syndrome (AIDS) and human immunodeficiency virus (HIV) infection. Among the classes of drugs which have shown efficacy against HIV, nucleoside-based reverse transcriptase inhibitors (NRTIs) have been extensively investigated in both their basic and therapeutic aspects. The basic mechanism of the effects of NRTIs relies on interaction with both viral and host cell functions. This implies that NRTIs could act not only by inhibiting viral genome replication, but also by interfering with some basic mechanism regulating cell growth and death. According to these characteristics, NRTIs might share several similarities with antineoplastic agents, including side effects. In this article, we have briefly reviewed the pharmacological activities of NRTIs in viral replication, neoplastic growth and cellular functions. These aspects might be involved both in the beneficial and adverse effects of NRTIs.
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Affiliation(s)
- B Macchi
- Department of Neuroscience, University of Rome Tor Vergata, Via Montpellier, 00133 Rome, Italy
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23
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Balestrieri E, Forte G, Matteucci C, Mastino A, Macchi B. Effect of lamivudine on transmission of human T-cell lymphotropic virus type 1 to adult peripheral blood mononuclear cells in vitro. Antimicrob Agents Chemother 2002; 46:3080-3. [PMID: 12183277 PMCID: PMC127437 DOI: 10.1128/aac.46.9.3080-3083.2002] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The effects of lamivudine (3TC) on in vitro infection of peripheral blood mononuclear cells (PBMC) from healthy donors with human T-cell lymphotropic virus type 1 (HTLV-1) were investigated. Direct measures of viral replication (viral DNA, RNA, and protein) all gave similar, very high 50% inhibitory concentrations in comparison with those previously reported for zidovudine. Nevertheless, 3TC inhibited HTLV-1-driven long-term growth of infected PBMC in vitro at concentrations (6.25 micro M) which had poor or no direct antiviral effects, suggesting that another mechanism may be playing a role.
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Affiliation(s)
- Emanuela Balestrieri
- Department of Microbiological, Genetic and Molecular Science, University of Messina, Messina, Italy
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24
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Yuen MF, Wong DKH, Sablon E, Yuan HJ, Sum SM, Hui CK, Chan AOO, Wong BCY, Lai CL. Hepatitis B Virus Genotypes B and C Do Not Affect the Antiviral Response to Lamivudine. Antivir Ther 2002. [DOI: 10.1177/135965350300800610] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
To date, there have been no studies examining the role of hepatitis B virus (HBV) genotypes on the response to lamivudine therapy and the development of YMDD mutations. The present study aimed at determining any differences in the antiviral response and risk of YMDD mutations between lamivudine-treated patients with HBV genotype B and genotype C. Eighty-two patients receiving lamivudine were recruited. HBV genotypes at baseline and YMDD mutations at week 52 were determined by line probe assays (LiPA). HBV DNA levels were determined by the Cobas Amplicor HBV Monitor Test. Seventeen (20.7%) and sixty-four (78%) patients had single genotypes of B and C, respectively. At both week 24 and 52 there were no differences in the median reduction of HBV DNA levels (median 4 logs drop), the median reduction of alanine aminotransferase (ALT) levels, and the proportion with normalization of ALT [8/8 (100%) vs 26/37 (70.3%), P=0.19] between patients with genotypes B and C. The rate of HBeAg seroconversion [3/17 (17.6%) vs 6/64 (9.4%), P=0.39] and the chance of YMDD mutation development [3/17 (17.6%) vs 12/64 (18.8%), P=1.0] at week 52 were also similar between patients with genotype B and C, respectively. In conclusion, there was no difference in the antiviral response and the rate of development of YMDD mutations in Chinese patients with genotype B and C after 1 year of lamivudine. Determination of HBV genotypes before lamivudine therapy was probably not an important pre-treatment investigation to predict antiviral responses in Chinese patients.
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Affiliation(s)
- Man-Fung Yuen
- Division of Gastroenterology and Hepatology, Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong
| | - Danny Ka-Ho Wong
- Division of Gastroenterology and Hepatology, Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong
| | | | - He-Jun Yuan
- Division of Gastroenterology and Hepatology, Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong
| | - Siu-Man Sum
- Division of Gastroenterology and Hepatology, Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong
| | - Chee-Kin Hui
- Division of Gastroenterology and Hepatology, Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong
| | - Annie On-On Chan
- Division of Gastroenterology and Hepatology, Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong
| | - Benjamin Chun-Yu Wong
- Division of Gastroenterology and Hepatology, Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong
| | - Ching-Lung Lai
- Division of Gastroenterology and Hepatology, Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong
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25
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Fernandez-Bolaños JG, al-Masoudi NA, Maya I. Sugar derivatives having sulfur in the ring. Adv Carbohydr Chem Biochem 2002; 57:21-98. [PMID: 11836944 DOI: 10.1016/s0065-2318(01)57015-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- J G Fernandez-Bolaños
- Departamento de Química Orgánica, Facultad de Química, Universidad de Sevilla Apartado 553, E-41071 Seville, Spain
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26
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Julander JG, Sidwell RW, Morrey JD. Characterizing antiviral activity of adefovir dipivoxil in transgenic mice expressing hepatitis B virus. Antiviral Res 2002; 55:27-40. [PMID: 12076749 DOI: 10.1016/s0166-3542(01)00223-6] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Oral adefovir dipivoxil (ADV) reduced viral load in transgenic mice expressing hepatitis B virus (HBV). Liver HBV DNA was reduced to <0.1 pg of viral DNA per microg of total DNA (pg/microg) following oral ADV therapy at a dosage of 100 mg/kg/day twice daily for 10 days as compared to a mean of 3.0 pg/microg for the placebo control group. Oral ADV treatment also reduced serum HBV DNA to 3.5 log10 genomic equivalents (ge)/ml compared to 5.3 log10 ge/ml for the placebo control group. With once daily treatments, ADV antiviral activity reached near maximum viral reduction by day 10 in the liver and reached an endpoint of liver virus inhibition at 1.0 mg/kg/day. The minimum effective dose was less than 0.1 mg/kg/day using inhibition of serum virus. Lamivudine (3TC) given orally at 500 mg/kg/day using the same treatment schedule marginally reduced the serum HBV DNA by 4-fold, but did not significantly reduce HBV liver DNA. Serum titer reduction was also identified in untreated or placebo-treated animals, which may have been caused by the stress of pre-treatment bleeding and multiple oral gavage treatments. This trauma/placebo-effect may have masked the extent of viral reduction in the serum in ADV- and 3TC-treated animals. Liver HBV RNA was not reduced by oral ADV treatments. The lack of RNA reduction was expected, because the HBV transgene is stably integrated into the chromosome and ADV inhibits polymerase activity after transcription of pregenomic RNA. ADV was identified to have potent anti-HBV activity in this HBV transgenic mouse model and could serve as a suitable positive control for future drug discovery experiments.
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Affiliation(s)
- Justin G Julander
- Animal, Dairy, and Veterinary Sciences Department, Institute for Antiviral Research, Utah State University, 4700 Old Main Hill, Logan, UT 84322-4700, USA
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27
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Song YH, Lin JS, Liu NZ, Kong XJ, Xie N, Wang NX, Jin YX, Liang KH. Anti-HBV hairpin ribozyme-mediated cleavage of target RNA in vitro. World J Gastroenterol 2002; 8:91-4. [PMID: 11833079 PMCID: PMC4656634 DOI: 10.3748/wjg.v8.i1.91] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To study the preparation and cleavage activity of HpRz directed against the transcript of HBV core gene in vitro.
METHODS: HpRz gene designed by computer targeting the transcript of HBV core gene was cloned into the vector p1.5 between 5’-cis-Rz and 3’-cis-Rz. 32p-labeled HpRz transcript proved whether the vector fit for the preparation of hairpin ribozyme in vitro. 32p-labeled pKC transcript containing HBV core region as target-RNA was transcribed using T7 RNA polymerase and purified by denaturing PAGE. Cold HpRz transcript was incubated with 32p-labeled target-RNAs under different conditions and radio autographed after denaturing polyacrylamide gel electrophoresis.
RESULTS: HpRz has the specific ability of cleavage of target RNA at 37 °C and 12 mM MgCl2. Km = 26.31 nmol/L, Kcat = 0.18/min. These results revealed that the design of HpRz was correct.
CONCLUSION: HpRz prepared in this study possesses specific catalytic activity from the identification of cleavage activity. These results indicate that hairpin ribozyme may intracellularly inhibit the replication of HBV, therefore it may become a novel potent weapon for the treatment of hepatitis B.
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Affiliation(s)
- Yu-Hu Song
- Institute of Liver Diseases, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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28
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Abstract
This review updates the treatment of chronic hepatitis B infection. Complete eradication of hepatitis B virus (HBV) is not possible, so the efficacy of treatment has to be assessed by whether it can limit long-term cirrhosis-related complications. We discuss two major groups of treatments--immunomodulators (interferon alfa, thymosin alpha1, therapeutic vaccines) and nucleoside analogues (lamivudine, adefovir, entecavir, emtricitabine, beta-L-2'-deoxythymidine). To date, interferon alfa and lamivudine are the only two agents approved for chronic hepatitis B. Interferon alfa achieves a short-term outcome of around 20-30% loss of HBeAg. The efficacy is lower in Chinese patients, who are immunotolerant to HBV because of acquisition of the disease during early childhood, than in white patients. This difference is further confirmed on long-term follow-up. Interferon alfa does not affect the development of cirrhosis-related complications in Chinese patients, whereas in white patients, the frequency of long-term complications is reduced if interferon alfa is successful in inducing loss of HBeAg. Lamivudine profoundly suppresses viral replication and achieves an HBeAg seroconversion rate similar to that of interferon alfa. It is equally effective in Chinese and white patients because the main antiviral mechanism is through inhibition of reverse transcription of HBV during viral replication. However, long-term lamivudine therapy is associated with emergence of HBV variants, YMDD variants. Newer nucleoside analogues are being extensively investigated by studies in vivo and in vitro. Combination therapy with two or three nucleoside analogues or immunomodulators plus nucleoside analogues will be the future direction of treatment of chronic hepatitis B.
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Affiliation(s)
- M F Yuen
- Department of Medicine, University of Hong Kong, Queen Mary Hospital, Hong Kong SAR, China
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29
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Abstract
Over two billion people around the world have been infected with hepatitis B virus, of whom over 350 million are chronic carriers. Some 25% of carriers develop progressive liver disease. The annual mortality from hepatitis B infection and its sequelae is 1-2 million people worldwide.The following current topics are reviewed: immunization strategies against hepatitis B and the kinetics and antibody response; the controversy on screening blood donors for anti-core antibodies; mutations of hepatitis B surface antigen, including evidence that not all such mutants are detectable by current laboratory tests and, finally, the introduction of second generation nucleoside analogues for treatment of chronic hepatitis B infection, including treatment of patients with decompensated liver disease and liver transplantation.
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Affiliation(s)
- J N Zuckerman
- Academic Centre for Travel Medicine and Vaccines, WHO Collaborating Centre for Reference and Research on Viral Diseases, Royal Free Campus, Royal Free and University College Medical School, London NW3 2PF, UK
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