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1.
BMC Vet Res ; 16(1): 484, 2020 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-33317521

RESUMO

BACKGROUND: Transition period (TP) is characterised by physiological and metabolic changes contributing to immunodysregulation. Since knowledge about this period in sheep is scarce, we analysed changes in selected immune variables during the TP in ewes and whether dietary magnesium (Mg) supplementation could modulate these immune variables. Pregnant ewes (2nd and 3rd lactation) were divided into a control group (CONT, n = 9) and a Mg group (MAG, n = 10) supplemented with Mg oxide resulting in a daily Mg intake of approximately 0.30 and 0.38% (MAG) of dry matter during ante- (a.p.) and post-partum (p.p.) periods, respectively. Blood samples were collected between days (d) 30 a.p. and d 30 p.p.. Whole blood neutrophil phagocytic activity, monocyte subset (classical cM, intermediate intM, non-classical ncM) composition and the proliferative capacity of lymphocytes were determined flow cytometrically. At d 14 a.p., all ewes were vaccinated against Mycobacterium avium subsp. paratuberculosis (MAP). RESULTS: Both groups showed a sharp increase in the total leukocyte counts (TLC) and neutrophil counts (P < 0.0001), at d 1 p.p., while, monocytes and their subpopulations displayed the highest values at d 30 p.p. (P ≤ 0.05). At d 1 p.p. the neutrophil phagocytic activity was higher (P < 0.05) in MAG ewes. Throughout the TP, the proliferative response of CD4+ cells was significantly higher in the MAG group (P < 0.05). Ewes in both groups responded with an increase in the TLC, neutrophil numbers (P ≤ 0.05) and ncM (P < 0.001) 24 h post vaccination, whereas monocytes and cM dropped in numbers (P ≤ 0.05). Numbers of intM only increased in MAG ewes (P < 0.05), whereas lymphocyte numbers decreased (P < 0.01). Mg supplementation did not affect the significant increase in MAP-specific antibodies at d 7 and 21 post vaccination. Total Mg and Ca serum levels did not show any differences between the two groups. CONCLUSION: Whereas TP-associated fluctuations in blood leukocyte numbers are not influenced by Mg supplementation, neutrophil phagocytic activity, the proliferative capacity of CD4+ cells and the cellular response within 24 h after a vaccination are subject to modulation.


Assuntos
Dieta/veterinária , Magnésio/farmacologia , Período Pós-Parto/imunologia , Ração Animal/análise , Animais , Contagem de Linfócito CD4 , Proliferação de Células , Feminino , Contagem de Leucócitos/veterinária , Mycobacterium avium subsp. paratuberculosis/imunologia , Paratuberculose/prevenção & controle , Fagocitose , Gravidez , Ovinos , Doenças dos Ovinos/imunologia , Doenças dos Ovinos/prevenção & controle , Carneiro Doméstico , Vacinação/veterinária
2.
Gut ; 66(10): 1829-1837, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-27196570

RESUMO

OBJECTIVE: As pathogen sensors, Toll-like receptors (TLR) play a role in the first defence line during HCV infection. However, the impact of the DNA sensor TLR9 on the natural course of HCV infection is unknown. To address this, TLR9 promoter polymorphisms (single nucleotide polymorphisms (SNPs)) rs187084 and rs5743836 were investigated for their effect on disease progression. DESIGN: Therefore, the TLR9 SNPs and the interferon lambda 4 (IFNL4) rs12979860 were genotyped in chronically HCV type 1 infected (n=333), in patients who spontaneously cleared the infection (n=161), in the Swiss HCV cohort (n=1057) and the well-characterised German (n=305) and Irish (n=198) 'anti-D' cohorts. Functional analyses were done with promoter reporter constructs of human TLR9 in B cells and assessing TLR9 mRNA levels in whole blood of healthy volunteers. RESULTS: The TLR9 rs187084 C allele was associated with spontaneous virus clearance in women of the study cohort (OR=2.15 (95% CI 1.18 to 3.90) p=0.012), of the Swiss HCV cohort (OR=2.06 (95% CI 1.02 to 4.18) p=0.044) and in both 'anti-D' cohorts (German: OR=2.01 (95% CI 1.14 to 3.55) p=0.016; Irish: OR=1.93 (95% CI 1.10 to 3.68) p=0.047). Multivariate analysis in the combined study and Swiss HCV cohorts supported the results (OR=1.99 (95% CI 1.30 to 3.05) p=0.002). Functional analyses revealed higher transcriptional activities for both TLR9 variants and an association of the C allele of rs5743836 with allele-specific TLR9 mRNA regulation by oestrogens in women. CONCLUSIONS: TLR9 promoter SNPs are associated with the natural course of HCV infection and show higher transcriptional activities. Our results imply the DNA sensor TLR9 in natural immunity against the RNA virus, HCV.


Assuntos
Hepatite C Crônica/genética , Interleucinas/genética , RNA Mensageiro/sangue , Receptor Toll-Like 9/genética , Adulto , Idoso , Alelos , Progressão da Doença , Feminino , Regulação da Expressão Gênica/genética , Alemanha , Haplótipos , Humanos , Irlanda , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Remissão Espontânea , Estudos Retrospectivos , Fatores Sexuais , Suíça , Transcrição Gênica
3.
PLoS One ; 10(6): e0128069, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26057627

RESUMO

UNLABELLED: Although sofosbuvir has been approved for patients with genotypes 2/3 (G2/3), many parts of the world still consider pegylated Interferon alpha (P) and ribavirin (R) as standard of care for G2/3. Patients with rapid virological response (RVR) show response rates >80%. However, SVR (sustained virological response) in non-RVR patients is not satisfactory. Longer treatment duration may be required but evidence from prospective trials are lacking. A total of 1006 chronic HCV genotype 2/3 patients treated with P/R were recruited into a German HepNet multicenter screening registry. Of those, only 226 patients were still HCV RNA positive at week 4 (non-RVR). Non-RVR patients with ongoing response after 24 weeks P-2b/R qualified for OPTEX, a randomized trial investigating treatment extension of additional 24 weeks (total 48 weeks, Group A) or additional 12 weeks (total 36 weeks, group B) of 1.5 µg/kg P-2b and 800-1400 mg R. Due to the low number of patients without RVR, the number of 150 anticipated study patients was not met and only 99 non-RVR patients (n=50 Group A, n=49 Group B) could be enrolled into the OPTEX trial. Baseline factors did not differ between groups. Sixteen patients had G2 and 83 patients G3. Based on the ITT (intention-to-treat) analysis, 68% [55%; 81%] in Group A and 57% [43%; 71%] in Group B achieved SVR (p= 0.31). The primary endpoint of better SVR rates in Group A compared to a historical control group (SVR 70%) was not met. In conclusion, approximately 23% of G2/3 patients did not achieve RVR in a real world setting. However, subsequent recruitment in a treatment-extension study was difficult. Prolonged therapy beyond 24 weeks did not result in higher SVR compared to a historical control group. TRIAL REGISTRATION: ClinicalTrials.gov NCT00803309.


Assuntos
Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Interferon-alfa/uso terapêutico , Ribavirina/uso terapêutico , Feminino , Genótipo , Hepacivirus/efeitos dos fármacos , Humanos , Interferon-alfa/efeitos adversos , Interferon-alfa/farmacologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , Recidiva , Ribavirina/efeitos adversos , Ribavirina/farmacologia , Inquéritos e Questionários , Resultado do Tratamento
4.
PLoS One ; 9(10): e108751, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25302676

RESUMO

Evidence based clinical guidelines are implemented to treat patients efficiently that include efficacy, tolerability but also health economic considerations. This is of particular relevance to the new direct acting antiviral agents that have revolutionized treatment of chronic hepatitis C. For hepatitis C genotypes 2/3 interferon free treatment is already available with sofosbuvir plus ribavirin. However, treatment with sofosbuvir-based regimens is 10-20 times more expensive compared to pegylated interferon alfa and ribavirin (PegIFN/RBV). It has to be discussed if PegIFN/RBV is still an option for easy to treat patients. We assessed the treatment of patients with chronic hepatitis C genotypes 2/3 with PegIFN/RBV in a real world setting according to the latest German guidelines. Overall, 1006 patients were recruited into a prospective patient registry with 959 having started treatment. The intention-to-treat analysis showed poor SVR (GT2 61%, GT3 47%) while patients with adherence had excellent SVR in the per protocol analysis (GT2 96%, GT3 90%). According to guidelines, 283 patients were candidates for shorter treatment duration, namely a treatment of 16 weeks (baseline HCV-RNA <800.000 IU/mL, no cirrhosis and RVR). However, 65% of these easy to treat patients have been treated longer than recommended that resulted in higher costs but not higher SVR rates. In conclusion, treatment with PegIFN/RBV in a real world setting can be highly effective yet similar effective than PegIFN± sofosbuvir/RBV in well-selected naïve G2/3 patients. Full adherence to guidelines could be further improved, because it would be important in the new era with DAA, especially to safe resources.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Fatores Imunológicos/uso terapêutico , Interferon-alfa/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antivirais/química , Feminino , Hepacivirus/efeitos dos fármacos , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C Crônica/diagnóstico , Humanos , Fatores Imunológicos/química , Interferon-alfa/química , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/química , Estudos Prospectivos , Adulto Jovem
5.
Ann Hepatol ; 12(2): 190-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23396729

RESUMO

INTRODUCTION: Complete suppression of viral replication is crucial in chronic HCV treatment in order to prevent relapse and resistance development. We wanted to find out which factors influence the period from being already HCV RNA negative by bDNA assay (< 615 IU/mL) to become undetectable by the more sensitive TMA test (< 5.3 IU/mL). MATERIAL AND METHODS: Evaluated were 433 HCV type 1-infected patients. All of them received 1.5 ug/kg Peg-IFNα-2b plus ribavirin for 18-48 weeks. bDNA was performed weekly during the first 8 weeks and thereafter at weeks 12, 24, and 48. Patients who became bDNA undetectable were additionally analysed by TMA. RESULTS: Of the 309 patients with on-treatment response (< 615 IU/mL), 289 also reached undetectable HCV RNA levels by TMA. Multivariate analysis revealed that viremia ≤ 400,000 IU/mL (p = 0.001), fast initial virologic decline (p = 0.004) and absence of fibrosis (p = 0.035) were independent predictors of an accelerated on-treatment response by TMA assay in already bDNA negative patients. bDNA negative patients becoming HCV RNA undetectable by TMA within the following 3 weeks had a frequency of relapse of 21%, whereas those showing TMA negativity after 3 weeks relapsed in 38% (p = 0.001). In RVR patients (bDNA < 615 IU/mL at week 4) the corresponding relapse rates were 15.3% vs. 37.5%, respectively (p = 0.003). CONCLUSION: Early viral kinetics, baseline viremia and fibrosis stage are important tools to predict persistent minimal viremia during interferon-based therapy. The data have implications for designing a more refined treatment strategy in HCV infection, even in the setting of protease inhibitor-based triple treatment.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Distribuição de Qui-Quadrado , DNA Viral/sangue , Quimioterapia Combinada , Feminino , Genótipo , Alemanha , Hepacivirus/genética , Hepacivirus/crescimento & desenvolvimento , Hepatite C Crônica/sangue , Hepatite C Crônica/complicações , Hepatite C Crônica/diagnóstico , Humanos , Interferon alfa-2 , Estimativa de Kaplan-Meier , Cirrose Hepática/diagnóstico , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fenótipo , Modelos de Riscos Proporcionais , RNA Viral/sangue , Proteínas Recombinantes/uso terapêutico , Recidiva , Ribavirina/uso terapêutico , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Viremia/diagnóstico , Viremia/tratamento farmacológico , Replicação Viral/efeitos dos fármacos , Adulto Jovem
6.
Eur J Gastroenterol Hepatol ; 25(4): 416-20, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23211286

RESUMO

BACKGROUND: In settings such as needle-stick injuries or intravenous drug abuse, immediate knowledge of the anti-hepatitis C virus (HCV) serostatus instead of waiting for the results of a laboratory-based test can be important to guide further medical procedures and appropriate hygienic advises. Thus, a rapid on-site anti-HCV test was evaluated in daily clinical routine and compared with a laboratory-based certified assay. PATIENTS AND METHODS: Ten microliters of serum or EDTA whole blood was analyzed using a chromatographic immunoassay (Toyo anti-HCV test). Results were available on-site 5-15 min after sample centrifugation. The Architect anti-HCV test served as a reference method. RESULTS: Sera of 189 patients were analyzed (without HCV infection: n=105; HCV infection: n=84). The assay was evaluable in 185 cases (98%). The sensitivity and specificity were 99 and 88%, respectively. With EDTA whole blood, the test was evaluable in 47/52 samples (90%). Forty-six of 47 evaluable EDTA tests were concordant with serum results. The one HCV patient with an unevaluable serum test was diagnosed correctly with the EDTA sample. CONCLUSION: The rapid chromatographic anti-HCV immunoassay has limited specificity, which impairs clinical practicability. A positive result warrants re-evaluation with a certified serologic assay.


Assuntos
Anticorpos Anti-Hepatite C/sangue , Hepatite C/diagnóstico , Reações Falso-Positivas , Feminino , Hepacivirus/imunologia , Humanos , Imunoensaio/métodos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Projetos Piloto , Sistemas Automatizados de Assistência Junto ao Leito , Sensibilidade e Especificidade
7.
Antivir Ther ; 17(6): 1049-58, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22892524

RESUMO

BACKGROUND: Tenofovir disoproxil fumarate (TDF), an acyclic nucleotide analogue was shown to be effective in many HBV-infected patients with resistance to adefovir dipivoxil (ADV). This observation is intriguing because in vitro studies show that HBV mutations selected by ADV confer cross-resistance to TDF. To assess the clinical relevance of this cross-resistance, we studied the evolution of HBV polymerase gene variants in patients with genotypic resistance against ADV (rtN236T and/or rtA181V/T) during TDF treatment. METHODS: In 10 HBV-monoinfected patients (9 male, mean age 47 ±11 [range 27-67] years, 6 hepatitis B e antigen-positive) with virological breakthrough during ADV treatment associated with the mutations rtN236T and/or rtA181T/V, HBV polymerase gene variants were studied during up to 24 months of consecutive monotherapy with TDF by population sequencing, line probe assay and clonal analysis. RESULTS: In all patients, switching to TDF resulted in a continuous reduction of HBV DNA from a median of 7.6 (4.6-9.4) log(10) copies/ml to 3.3 (2-5) log(10) copies/ml, remaining in 7 patients >400 copies/ml at 12 months. ADV-resistance mutations remained detectable throughout the whole observation period in most patients. Apart from an M204Q mutation in one sample, no new HBV polymerase gene mutations were found. In two patients with low level viraemia after 72 weeks of TDF, adding lamivudine led to a complete response within a few weeks. CONCLUSIONS: ADV-resistant HBV variants may further become selected during TDF treatment, however they cause only a mild decrease in TDF susceptibility.


Assuntos
Adenina/análogos & derivados , Antivirais/farmacologia , Evolução Molecular , Produtos do Gene pol/genética , Hepatite B/tratamento farmacológico , Organofosfonatos/farmacologia , Adenina/farmacologia , Adulto , Idoso , Clonagem Molecular , DNA Viral/sangue , Farmacorresistência Viral , Substituição de Medicamentos , Escherichia coli/genética , Escherichia coli/metabolismo , Feminino , Seguimentos , Produtos do Gene pol/metabolismo , Hepatite B/metabolismo , Hepatite B/virologia , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/genética , Vírus da Hepatite B/patogenicidade , Humanos , Lamivudina/farmacologia , Masculino , Pessoa de Meia-Idade , Mutação , Tenofovir , Viremia/tratamento farmacológico , Viremia/metabolismo , Viremia/virologia
8.
World J Gastroenterol ; 18(12): 1339-47, 2012 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-22493547

RESUMO

AIM: To analyzes the decision whether patients with chronic hepatitis C virus (HCV) infection are treated or not. METHODS: This prospective cohort study included 7658 untreated patients and 6341 patients receiving pegylated interferon α 2a/ribavirin, involving 434 physicians/institutions throughout Germany (377 in private practice and 57 in hospital settings). A structured questionnaire had to be answered prior to the treatment decision, which included demographic data, information about the personal life situation of the patients, anamnesis and symptomatology of hepatitis C, virological data, laboratory data and data on concomitant diseases. A second part of the study analyzes patients treated with pegylated interferon α2a. All questionnaires included reasons against treatment mentioned by the physician. RESULTS: Overall treatment uptake was 45%. By multivariate analysis, genotype 1/4/5/6, HCV-RNA ≤ 520,000 IU/mL, normal alanine aminotransferase (ALT), platelets ≤ 142,500/µL, age > 56 years, female gender, infection length > 12.5 years, concomitant diseases, human immunodeficiency virus co-infection, liver biopsy not performed, care in private practice, asymptomatic disease, and unemployment were factors associated with reduced treatment rate. Treatment and sustained viral response rates in migrants (1/3 of cohort) were higher than in German natives although 1/3 of migrants had language problems. Treatment rate and liver biopsy were higher in clinical settings when compared to private practice and were low when ALT and HCV-RNA were low. CONCLUSION: Some reasons against treatment were medically based whereas others were related to fears, socio-economical problems, and information deficits both on the side of physicians and patients.


Assuntos
Antivirais/uso terapêutico , Tomada de Decisões , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Padrões de Prática Médica , Recusa em Tratar , Ribavirina/uso terapêutico , Adulto , Estudos de Coortes , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteínas Recombinantes/uso terapêutico , Inquéritos e Questionários , Recusa do Paciente ao Tratamento
9.
Clin Infect Dis ; 53(11): 1111-4, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22021919

RESUMO

This study demonstrates that a more precise prediction of the individual relapse risk in chronic hepatitis C virus genotype 1 infection can be obtained by kinetics of minimal residual viremia at weeks 4, 8, and 12 in combination with levels of baseline viremia. These data may also help to further individualize new protease inhibitor-based triple therapy regimens.


Assuntos
Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Carga Viral , Viremia , Antivirais/administração & dosagem , Genótipo , Hepacivirus/classificação , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Humanos , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Polietilenoglicóis/administração & dosagem , Proteínas Recombinantes/administração & dosagem , Recidiva , Ribavirina/administração & dosagem , Medição de Risco
10.
Gastroenterology ; 141(5): 1656-64, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21784046

RESUMO

BACKGROUND & AIMS: Guidelines recommend that patients with chronic hepatitis C virus (HCV) infection be treated with pegylated interferon and ribavirin for 24, 48, or 72 weeks, based on their virologic response to treatment. We investigated the effects of treating patients for individualized durations. METHODS: We treated 398 treatment-naïve patients who had HCV genotype 1 infections with pegylated interferon alfa-2b and ribavirin for 24, 30, 36, 42, 48, 60, or 72 weeks (mean of 39 weeks, termed individualized therapy); the duration of therapy was determined based on baseline viral load and the time point at which HCV RNA levels became undetectable (measured at weeks 4, 6, 8, 12, 24, and 30). Results were compared with those of 225 patients who received standard treatment for 48 weeks (mean of 38 weeks). RESULTS: Rates of sustained virologic response (SVR) were 55% among patients who received individualized treatment and 48% among those who received standard treatment (P < .0001 for noninferiority). SVR rates, according to the time point at which HCV RNA levels became undetectable, did not differ significantly between groups. Patients with a rapid virologic response (undetectable levels of HCV RNA at week 4) who were treated for 24 to 30 weeks achieved high rates of SVR (86%-88%). Rates of SVR increased among slow responders who first tested negative for HCV RNA at week 24 and were treated for 60 to 72 weeks compared with those treated for 48 weeks (60%-68% vs 43%-44%). The CC polymorphism at IL28B rs129797860 was associated with an increased rate of SVR compared with the CT/TT polymorphism (P < .0001) at baseline but not among patients who had undetectable levels of HCV RNA following treatment. CONCLUSIONS: Individualizing treatment of patients with chronic HCV genotype 1 infections for 24 to 72 weeks results in high rates of SVR among rapid responders and increases SVR among slow responders.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Medicina de Precisão/métodos , Ribavirina/uso terapêutico , Adolescente , Adulto , Idoso , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Genótipo , Alemanha , Hepacivirus/genética , Humanos , Interferon alfa-2 , Interferon-alfa/efeitos adversos , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/efeitos adversos , RNA Viral/sangue , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Ribavirina/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
11.
Gastroenterology ; 139(4): 1207-17, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20600025

RESUMO

BACKGROUND & AIMS: We compared treatments for patients with chronic hepatitis B virus (HBV) infection who had an incomplete response to adefovir dipivoxil (ADV). We evaluated a combination of fixed-dose emtricitabine (FTC) and tenofovir disoproxil fumarate (TDF) from the start (early combination) versus TDF as monotherapy. METHODS: Patients (n = 105) were randomly assigned to groups given TDF (n = 53) or FTC/TDF (n = 52). End points included HBV DNA suppression, biochemical and serologic response, and response by baseline or developed resistance mutations through 48 weeks of treatment. Patients given TDF monotherapy had the option to receive FTC, as fixed-dose FTC/TDF, if viremia persisted after week 24. RESULTS: At baseline, patients' mean HBV DNA level was 5.97 log(10) copies/mL, and 58% had received lamivudine (LAM); LAM- and ADV-associated mutations were detected in 13 and 10 patients, respectively, by population sequencing and in 14 and 18 patients, respectively, by reverse hybridization line probe assay (INNO-LiPA HBV DR). Through week 24 (direct comparison of blinded therapy), viral decay curves were identical between groups. At week 48, 81% of patients initially given TDF or TDF/FTC had HBV DNA levels below 400 copies/mL. The presence of baseline LAM- or ADV-associated mutations did not affect response. Adherence to therapy appeared to be the primary factor associated with HBV DNA levels below 400 copies/mL at week 48. CONCLUSIONS: TDF monotherapy and the combination of FTC and TDF had similar efficacy in patients with incomplete viral suppression after therapy with ADV; response was not influenced by the presence of baseline LAM- or ADV-associated mutations. Initial monotherapy followed by combination therapy was as effective as early combination therapy.


Assuntos
Adenina/análogos & derivados , Antivirais/uso terapêutico , Desoxicitidina/análogos & derivados , Hepatite B Crônica/tratamento farmacológico , Organofosfonatos/uso terapêutico , Adenina/efeitos adversos , Adenina/uso terapêutico , Adolescente , Adulto , Alanina Transaminase/sangue , Antivirais/administração & dosagem , DNA Viral/sangue , Desoxicitidina/uso terapêutico , Método Duplo-Cego , Farmacorresistência Viral , Quimioterapia Combinada , Emtricitabina , Feminino , Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Humanos , Masculino , Adesão à Medicação , Pessoa de Meia-Idade , Mutação , Organofosfonatos/efeitos adversos , Tenofovir
12.
Hepatology ; 51(1): 73-80, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19998272

RESUMO

UNLABELLED: Tenofovir disoproxil fumarate (TDF) has demonstrated high antiviral efficacy in treatment-naive patients with chronic hepatitis B virus (HBV) infection but experience in nucleoside/nucleotide analogue (NA)-experienced patients is limited. In this retrospective multicenter study we therefore assessed the long-term efficacy of TDF monotherapy in patients with prior failure or resistance to different NA treatments. Criteria for inclusion were HBV DNA levels >4.0 log(10) copies/mL at the start and a minimum period of TDF therapy for at least 6 months. In all, 131 patients (mean age 42 +/- 12 years, 95 male, 65% hepatitis B e antigen [HBeAg]-positive) were eligible. Pretreatment consisted of either monotherapy with lamivudine (LAM; n = 18), adefovir (ADV; n = 8), and sequential LAM-ADV therapy (n = 73), or add-on combination therapy with both drugs (n = 29). Three patients had failed entecavir therapy. Resistance analysis in 113 of the 131 patients revealed genotypic LAM and ADV resistance in 62% and 19% of patients, respectively. The mean HBV DNA level at TDF baseline was 7.6 +/- 1.5 log(10) copies/mL. The overall cumulative proportion of patients achieving HBV DNA levels <400 copies/mL was 79% after a mean treatment duration of 23 months (range, 6-60). Although LAM resistance did not influence the antiviral efficacy of TDF, the presence of ADV resistance impaired TDF efficacy (100% versus 52% probability of HBV DNA <400 copies/mL, respectively). However, virologic breakthrough was not observed in any of the patients during the entire observation period. Loss of HBeAg occurred in 24% of patients and HBsAg loss occurred in 3%. No significant adverse events were noticed during TDF monotherapy. CONCLUSION: TDF monotherapy induced a potent and long-lasting antiviral response in NA-experienced patients with previous treatment failure. Our data may have implications for current add-on strategies.


Assuntos
Adenina/análogos & derivados , Hepatite B/tratamento farmacológico , Organofosfonatos/uso terapêutico , Adenina/uso terapêutico , Adolescente , Adulto , Estudos de Coortes , Farmacorresistência Viral , Feminino , Antígenos de Superfície da Hepatite B/análise , Antígenos E da Hepatite B/análise , Humanos , Lamivudina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tenofovir , Resultado do Tratamento
13.
Hepatology ; 50(2): 369-77, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19575366

RESUMO

UNLABELLED: Individualized treatment on the basis of early viral kinetics has been discussed to optimize antiviral therapy in chronic hepatitis C virus (HCV) infection. Individually tailored reduction in treatment duration in HCV type 1-infected patients represents one possible strategy. Four hundred thirty-three patients were randomly assigned to receive either 1.5 microg/kg peginterferon alfa-2b weekly plus 800-1,400 mg ribavirin daily for 48 weeks (n = 225, group A) or an individually tailored treatment duration (18-48 weeks; n = 208, group B). In the latter group, treatment duration was calculated using the time required to induce HCV RNA negativity (branched DNA [bDNA] assay; sensitivity limit, 615 IU/mL) multiplied by the factor 6. All bDNA negative samples were retested with the more sensitive transcription-mediated amplification (TMA) assay (sensitivity limit, 5.3 IU/mL). Sustained virologic response (SVR) rates were significantly lower in group B (34.6% versus 48.0% [P = 0.005]) due to higher relapse rates (32.7% versus 14.2% [P< 0.0005]). Important predictors of response were the levels of baseline viremia as well as the time to TMA negativity on treatment. Taking the simultaneous presence of low baseline viral load (<800,000 IU/mL) and a negative TMA test within the first 4 weeks as predictors for treatment response, SVR rates were comparable between both treatment schedules with an SVR probability of >80% obtained in patients treated for only 18 or 24 weeks. CONCLUSION: The individualized treatment strategy according to time to bDNA negativity failed to provide comparable efficacy compared with the standard of care. The inferiority of the individualized protocol may be explained by the use of a less sensitive HCV RNA assay, and also by underestimation of the importance of baseline viremia.


Assuntos
Antivirais/administração & dosagem , Hepatite C/tratamento farmacológico , Interferon-alfa/administração & dosagem , Polietilenoglicóis/administração & dosagem , RNA Viral/sangue , Ribavirina/administração & dosagem , Adolescente , Adulto , Idoso , Ensaio de Amplificação de Sinal de DNA Ramificado , Feminino , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Técnicas de Amplificação de Ácido Nucleico , Estudos Prospectivos , Proteínas Recombinantes , Resultado do Tratamento , Adulto Jovem
14.
Hepatology ; 44(2): 318-25, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16871563

RESUMO

Incomplete virological response to adefovir dipivoxil (ADV) has been observed in patients with lamivudine-resistant hepatitis B virus (HBV) infection and may be associated with developing resistance and disease progression. We therefore investigated whether the efficacy of viral suppression could be improved by replacing ADV with tenofovir disoproxil fumarate (TDF). Twenty patients with chronic HBV infection (18 HBeAg+), viral breakthrough during lamivudine therapy, and persistent viral replication (>10(4) copies/mL) after 15 months of ADV monotherapy (range 4-28 months) were treated with TDF 300 mg daily and were retrospectively analyzed. A screening for nucleoside/nucleotide analogue resistance mutations within the HBV polymerase gene was performed in all patients by direct sequencing. Within a median of 3.5 months, application of TDF led to undetectable HBV DNA in 19 of 20 patients, as demonstrated by suppression of HBV DNA below the detection limit of 400 copies/mL. Initially elevated ALT levels had normalized in 10 of 14 patients by the end of follow-up (median 12 months, range 3-24 months). Four patients lost HBeAg, after 3, 4, 5, and 16 months, and one patient seroconverted to anti-HBs after 16 months of TDF therapy. Lamivudine-associated mutations (rtV173L, rtL180M, rtM204V/I) could be detected in 6 patients at baseline of TDF, but this obviously did not influence the response. ADV-resistant mutations were not detected. No side effects were reported. In conclusion, these preliminary observations strongly suggest that TDF might be a highly effective rescue drug for HBV-infected patients with altered responsiveness to treatment with lamivudine and ADV.


Assuntos
Adenina/análogos & derivados , DNA Viral/genética , Farmacorresistência Viral , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B/tratamento farmacológico , Lamivudina/uso terapêutico , Organofosfonatos/uso terapêutico , Adenina/uso terapêutico , Adulto , Progressão da Doença , Feminino , Seguimentos , Produtos do Gene pol/efeitos dos fármacos , Produtos do Gene pol/genética , Genótipo , Hepatite B/virologia , Vírus da Hepatite B/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/efeitos dos fármacos , Estudos Retrospectivos , Inibidores da Transcriptase Reversa/uso terapêutico , Tenofovir , Resultado do Tratamento , Replicação Viral/efeitos dos fármacos
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