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1.
Ann Hepatol ; 26: 100540, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34583061

RESUMO

INTRODUCTION AND OBJECTIVES: Covalently closed circular (ccc)DNA acts as a viral reservoir in the liver of patients with a chronic hepatitis B (CHB) infection and can only be quantified in liver biopsies. Hepatitis B core-related antigen (HBcrAg) levels in plasma/serum have been proposed to reflect intrahepatic cccDNA-levels and may therefore monitor treatment efficacy. This study aimed to validate the relationship between HBcrAg and other intrahepatic and circulating viral markers in CHB patients with high viral load, before and after combination treatment. MATERIALS AND METHODS: Plasma/serum levels of HBcrAg, HBsAg, HBV-DNA, and HBV pregenomic RNA (HBV-pgRNA), and intrahepatic cccDNA and HBV-DNA levels and fibrosis scores were measured in 89 CHB patients with HBV-DNA levels of >100,000 copies/mL (17,182 IU/mL). Measurements were done before and after a 48-week treatment with pegylated interferon alfa-2a and adefovir in a prospective study (ISRCTN77073364). RESULTS: Baseline HBcrAg-values correlated strongly with intrahepatic cccDNA (ρ 0.77, p < 0.001), intrahepatic HBV-DNA (ρ 0.73, p < 0.001) and plasma/serum HBV-DNA (ρ 0.80, p < 0.001), HBV-pgRNA (ρ 0.80, p < 0.001), and to lesser extend HBsAg (ρ 0.56, p < 0.001). Baseline HBcrAg-levels could not predict functional cure (FC) but HBcrAg-levels declined more strongly in patients who developed FC or HBeAg-loss. Furthermore, most correlations persisted at the end of treatment and follow-up. CONCLUSIONS: HBcrAg reflects cccDNA transcription activity more accurately than HBsAg and may replace HBV-DNA as a marker during future treatment regimens, especially when cccDNA transcription is targeted or nucleot(s)ide analogues are included in the treatment regime.


Assuntos
DNA Viral/genética , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/tratamento farmacológico , Fígado/patologia , Adulto , Antivirais/uso terapêutico , Biomarcadores/metabolismo , Feminino , Seguimentos , Vírus da Hepatite B/genética , Hepatite B Crônica/imunologia , Hepatite B Crônica/virologia , Humanos , Fígado/imunologia , Fígado/metabolismo , Masculino , Estudos Prospectivos , Carga Viral
2.
Hepatology ; 77(2): E21, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35809235
3.
Hepatology ; 76(1): E24, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35318700
4.
Antimicrob Agents Chemother ; 59(5): 2746-55, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25712364

RESUMO

In treating hepatitis B virus (HBV) and human immunodeficiency virus (HIV) infections, the rapid reselection of resistance-associated variants (RAVs) is well known in patients with repeated exposure to the same class of antiviral agents. For chronic hepatitis C patients who have experienced virologic failure with direct-acting antiviral drugs, the potential for the reselection of persistent RAVs is unknown. Nine patients who received 14 days of telaprevir monotherapy were retreated with telaprevir-based triple therapy 4.3 to 5.7 years later. In four patients with virologic failure with both telaprevir-containing regimens, population-based and deep sequencing (454 GS-FLX) of the NS3 protease gene were performed before and at treatment failure (median coverage, 4,651 reads). Using deep sequencing, with a threshold of 1.0% for variant calling, no isolates were found harboring RAVs at the baseline time points. While population-based sequencing uncovered similar resistance patterns (V36M plus R155K for subtype 1a and V36A for subtype 1b) in all four patients after the first and second telaprevir treatments, deep sequencing analysis revealed a median of 7 (range, 4 to 23) nucleotide substitutions on the NS3 backbone of the resistant strains, together with large phylogenetic differences between viral quasispecies, making the survival of resistant isolates highly unlikely. In contrast, in a comparison of the two baseline time points, the median number of nucleotide exchanges in the wild-type isolates was only 3 (range, 2 to 8), reflecting the natural evolution of the NS3 gene. In patients with repeated direct antiviral treatment, a continuous evolution of HCV quasispecies was observed, with no clear evidence of persistence and reselection but strong signs of independent de novo generation of resistance. Antiviral therapy for chronic viral infections, like HIV, hepatitis B virus (HBV), or hepatitis C virus (HCV), faces several challenges. These viruses have evolved survival strategies and proliferate by escaping the host's immune system. The development of direct-acting antiviral agents is an important achievement in fighting these infections. Viral variants conferring resistance to direct antiviral drugs lead to treatment failure. For HIV/HBV, it is well known that viral variants associated with treatment failure will be archived and reselected rapidly during retreatment with the same drug/class of drugs. We explored the mechanisms and rules of how resistant variants are selected and potentially reselected during repeated direct antiviral therapies in chronically HCV-infected patients. Interestingly, in contrast to HIV and HBV, we could not prove long-term persistence and reselection of resistant variants in HCV patients who failed protease inhibitor-based therapy. This may have important implications for the potential to reuse direct-acting antivirals in patients who failed the initial direct antiviral treatment. (The phase IIIb study described in this paper is registered at ClinicalTrials.gov under registration number NCT01054573.).


Assuntos
Antivirais/uso terapêutico , Hepacivirus/efeitos dos fármacos , Hepacivirus/patogenicidade , Oligopeptídeos/uso terapêutico , Proteínas não Estruturais Virais/antagonistas & inibidores , Método Duplo-Cego , Hepatite C , Humanos
5.
Gastroenterology ; 147(2): 359-365.e1, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24818763

RESUMO

BACKGROUND & AIMS: The interferon-free regimen of ABT-450 (a protease inhibitor), ritonavir, ombitasvir (an NS5A inhibitor), dasabuvir (a non-nucleoside polymerase inhibitor), and ribavirin has shown efficacy in patients with hepatitis C virus (HCV) genotype 1b infection-the most prevalent subgenotype worldwide. We evaluated whether ribavirin is necessary for ABT-450, ritonavir, ombitasvir, and dasabuvir to produce high rates of sustained virologic response (SVR) in these patients. METHODS: We performed a multicenter, open-label, phase 3 trial of 179 patients with HCV genotype 1b infection, without cirrhosis, previously treated with peginterferon and ribavirin. Patients were assigned randomly (1:1) to groups given ABT-450, ritonavir, ombitasvir, and dasabuvir, with ribavirin (group 1) or without (group 2) for 12 weeks. The primary end point was SVR 12 weeks after treatment (SVR12). We assessed the noninferiority of this regimen to the rate of response reported (64%) for a similar population treated with telaprevir, peginterferon, and ribavirin. RESULTS: Groups 1 and 2 each had high rates of SVR12, which were noninferior to the reported rate of response to the combination of telaprevir, peginterferon, and ribavirin (group 1: 96.6%; 95% confidence interval, 92.8%-100%; and group 2: 100%; 95% confidence interval, 95.9%-100%). The rate of response in group 2 was noninferior to that of group 1. No virologic failure occurred during the study. Two patients (1.1%) discontinued the study owing to adverse events, both in group 1. The most common adverse events in groups 1 and 2 were fatigue (31.9% vs 15.8%) and headache (24.2% vs 23.2%), respectively. Decreases in hemoglobin level to less than the lower limit of normal were more frequent in group 1 (42.0% vs 5.5% in group 2; P < .001), although only 2 patients had hemoglobin levels less than 10 g/dL. CONCLUSIONS: The interferon-free regimen of ABT-450, ritonavir, ombitasvir, and dasabuvir, with or without ribavirin, produces a high rate of SVR12 in treatment-experienced patients with HCV genotype 1b infection. Both regimens are well tolerated, as shown by the low rate of discontinuations and generally mild adverse events. ClinicalTrials.gov number: NCT01674725.


Assuntos
Anilidas/uso terapêutico , Antivirais/uso terapêutico , Carbamatos/uso terapêutico , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Compostos Macrocíclicos/uso terapêutico , Ribavirina/uso terapêutico , Ritonavir/uso terapêutico , Sulfonamidas/uso terapêutico , Uracila/análogos & derivados , 2-Naftilamina , Adulto , Idoso , Anilidas/efeitos adversos , Antivirais/efeitos adversos , Biomarcadores/sangue , Carbamatos/efeitos adversos , Ciclopropanos , Quimioterapia Combinada , Europa (Continente) , Feminino , Genótipo , Hepacivirus/genética , Hepacivirus/crescimento & desenvolvimento , Hepatite C/diagnóstico , Humanos , Lactamas Macrocíclicas , Compostos Macrocíclicos/efeitos adversos , Masculino , Pessoa de Meia-Idade , Prolina/análogos & derivados , Porto Rico , RNA Viral/sangue , Ribavirina/efeitos adversos , Ritonavir/efeitos adversos , Sulfonamidas/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Estados Unidos , Uracila/efeitos adversos , Uracila/uso terapêutico , Valina , Carga Viral
6.
Eur Radiol ; 24(3): 638-48, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24158528

RESUMO

OBJECTIVE: To compare the diagnostic accuracy of TE and MRE and establish cutoff levels and diagnostic strategies for both techniques, enabling selection of patients for liver biopsy. METHODS: One hundred three patients with chronic hepatitis B or C and liver biopsy were prospectively included. Areas under curves (AUROC) were compared for TE and MRE for METAVIR fibrosis grade ≥ F2 and ≥F3. We defined cutoff values for selection of patients with F0-F1 (sensitivity >95%) and for significant fibrosis F2-F4 (specificity >95%). RESULTS: Following exclusions, 85 patients were analysed (65 CHB, 19 CHC, 1 co-infected). Fibrosis stages were F0 (n = 3), F1 (n = 53), F2 (n = 15), F3 (n = 8) and F4 (n = 6). TE and MRE accuracy were comparable [AUROCTE ≥ F2: 0.914 (95% CI: 0.857-0.972) vs. AUROCMRE ≥ F2: 0.909 (0.840-0.977), P = 0.89; AUROCTE ≥ F3: 0.895 (0.816-0.974) vs. AUROCMRE ≥ F3: 0.928 (0.874-0.982), P = 0.42]. Cutoff values of <5.2 and ≥8.9 kPa (TE) and <1.66 and ≥2.18 kPa (MRE) diagnosed 64% and 66% of patients correctly as F0-F1 or F2-F4. A conditional strategy in inconclusive test results increased diagnostic yield to 80%. CONCLUSION: TE and MRE have comparable accuracy for detecting significant fibrosis, which was reliably detected or excluded in two-thirds of patients. A conditional strategy further increased diagnostic yield to 80%. KEY POINTS: • Both ultrasound-based transient elastography and magnetic resonance elastography can assess hepatic fibrosis. • Both have comparable accuracy for detecting liver fibrosis in viral hepatitis. • The individual techniques reliably detect or exclude significant liver fibrosis in 66 %. • A conditional strategy for inconclusive findings increases the number of correct diagnoses.


Assuntos
Hepatite B Crônica/diagnóstico por imagem , Hepatite B Crônica/patologia , Hepatite C Crônica/diagnóstico por imagem , Hepatite C Crônica/patologia , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Adulto , Área Sob a Curva , Biópsia , Técnicas de Imagem por Elasticidade/métodos , Feminino , Hepatite B Crônica/complicações , Hepatite C Crônica/complicações , Humanos , Cirrose Hepática/etiologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC , Sensibilidade e Especificidade , Adulto Jovem
7.
Hepatology ; 54(5): 1538-46, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22045671

RESUMO

UNLABELLED: Retreatment with peginterferon alpha and ribavirin (PR) offers a limited chance of sustained virologic response (SVR) in patients who did not achieve SVR with prior PR treatment. This study evaluated the safety and efficacy of telaprevir-based treatment in combination with PR in well-characterized patients who did not achieve SVR in the control arms of three Phase II clinical trials. Patients eligible to enroll in this open-label nonrandomized study either met on-treatment criteria for nonresponse or relapsed after 48 weeks of treatment in the control arm of the three Phase II PROVE studies. The initial protocol was a 24-week regimen: 12 weeks of telaprevir and PR followed by an additional 12 weeks of PR. During the study the protocol was amended to extend PR to 48 weeks for patients with previous null response. All other patients with undetectable hepatitis C virus (HCV) RNA at weeks 4 and 12 received 24 weeks of therapy. Those with detectable HCV RNA at weeks 4 or 12 received a total of 48 weeks of therapy. The overall SVR rate was 59% (69/117). SVR rates with T12PR were 37% (19/51) in prior null responders, 55% (16/29) in prior partial responders, 75% (6/8) in prior breakthroughs, and 97% (28/29) in prior relapsers. The overall relapse rate was 16% (13/83). Adverse events were similar to those in previous trials with telaprevir, with 9% of patients discontinuing due to an adverse event (most commonly rash and anemia). CONCLUSION: This study demonstrated the benefit of retreatment with a telaprevir-based regimen for patients with well-characterized nonresponse (null and partial) or relapse to a prior course of PR treatment.


Assuntos
Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/administração & dosagem , Oligopeptídeos/administração & dosagem , Polietilenoglicóis/administração & dosagem , Ribavirina/administração & dosagem , Adulto , Antivirais/administração & dosagem , Antivirais/efeitos adversos , Quimioterapia Combinada/métodos , Feminino , Humanos , Interferon-alfa/efeitos adversos , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/efeitos adversos , Polietilenoglicóis/efeitos adversos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Recidiva , Retratamento/métodos , Ribavirina/efeitos adversos , Resultado do Tratamento , Adulto Jovem
8.
Viruses ; 14(6)2022 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-35746694

RESUMO

Hepatitis B Virus (HBV) encoded miRNAs were previously described and suggested to play a role in HBV replication and pathogenesis. In this study we aim to identify novel HBV encoded miRNAs in plasma and liver tissue samples from chronic hepatitis B (CHB) patients and determine their role in CHB pathogenesis and HBV replication. RNA next generation sequencing was performed on plasma and liver tissue samples from ten CHB patients and uninfected controls. The interaction of the potential miRNA-like structures with the RNA-induced silencing complex (RISC) was determined using RNA immunoprecipitation. Expression levels of the HBV encoded miRNAs were measured in liver tissue samples derived from a conformation cohort. The effect of HBV encoded miRNAs overexpression on HBV replication, expression of predicted target genes, and induction of interferon stimulated genes in cell lines were assessed. Three potential miRNA-like structures transcribed by HBV were identified in liver tissue, of which one miRNA, HBV-miR-6, was recognized using RISC. HBV-miR-6 expression was demonstrated in liver tissue samples from 52 of the 87 CHB patients. HBV-miR-6 levels correlated with hepatic HBV-DNA and plasma HBsAg levels. Overexpression of HBV-miR-6 in vitro did not affect HBV replication, and predicted both target genes expression and interferon stimulated genes expression after stimulation. A potential novel HBV encoded miRNA was identified and validated in liver tissue from CHB patients. It is suggested that HBV-miR-6 may play a role in the process of viral excretion or particle formation in vivo.


Assuntos
Hepatite B Crônica , MicroRNAs , Antivirais/uso terapêutico , Vírus da Hepatite B/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Interferons/genética
9.
Front Cell Infect Microbiol ; 12: 790964, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35719345

RESUMO

Background and Aims: With current standard of care a functional cure for Chronic Hepatitis B (CHB) is only achieved in 1-3% of patients and therefore novel therapies are needed. Disease activity during CHB can be determined by a broad range of virological biomarkers, however these biomarkers are also targets for novel treatment strategies. The aim of this study was to identify novel miRNAs that are differentially expressed in plasma and liver in CHB, and determine whether these miRNAs may serve as biomarkers of disease stage or treatment outcome. Methods: miRNA Next-Generation-Sequencing of plasma and liver samples from CHB patient and controls was performed to identify differentially expressed miRNAs. The identified candidate miRNAs were validated by qPCR in additional plasma and liver samples from two CHB cohorts. Results: Several miRNAs in plasma and liver were found to be differentially expressed between CHB patients and controls. Of the identified miRNAs expression levels of miR-122-5p in plasma were associated with plasma HBsAg, and plasma and liver HBV-DNA levels. Expression levels of miR-223-3p, miR-144-5p and miR-133a-3p in liver were associated with plasma alanine aminotransferase levels. No correlation was observed between miRNA expression levels at baseline and treatment outcome. Conclusions: Limited overlap between plasma and liver miRNAs was found, indicating that plasma miRNAs could be useful as biomarkers for treatment outcome or viral activity during treatment. Whereas liver miRNAs are more likely to be regulated by HBV and could be potential therapeutic targets to control viral activity in liver.


Assuntos
Hepatite B Crônica , MicroRNAs , Biomarcadores , Perfilação da Expressão Gênica , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B/genética , Hepatite B Crônica/complicações , Humanos , MicroRNAs/genética
10.
Gastroenterology ; 138(3): 913-21, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19852962

RESUMO

BACKGROUND & AIMS: The search for targeted anti-hepatitis C virus (HCV) drugs is driven by the adverse effect profile and limited efficacy of the current standard of care (pegylated interferon-alpha/ribavirin). In a first-in-human trial, we tested the safety, tolerability, and pharmacokinetics of the macrocyclic HCV NS3/4A protease inhibitor TMC435 in healthy volunteers, followed by HCV genotype 1-infected patients to assess antiviral activity. METHODS: The TMC435350-C101 study was a phase I, randomized, double-blind, placebo-controlled trial in 49 healthy volunteers, followed by an open-label, nonplacebo-controlled panel in 6 genotype 1 hepatitis C patients. Healthy volunteers received oral, single, ascending doses (up to 600 mg) or 5-day multiple ascending doses (200 mg twice daily or 100, 200, or 400 mg once daily). Patients received 200 mg once daily for 5 days. Pharmacokinetics and safety were evaluated for all panels, and plasma HCV-RNA levels were determined in patients. RESULTS: There were no serious adverse events, no grade 3 reactions, and no treatment-related discontinuations; pharmacokinetics supported a once daily dosing regimen. Plasma HCV-RNA levels dropped rapidly in all patients, with a median maximal reduction of 3.9-log(10) IU/mL and a median of 6 days to maximal reduction. The initial steep reduction of HCV-RNA (median 3.5-log(10) IU/mL at day 3) was followed by a more gradual decline that was maintained over the dosing period. No viral breakthroughs (>1-log(10) IU/mL HCV-RNA increase from nadir) were observed during treatment nor in the 3 days posttreatment; HCV-RNA returned to pretreatment levels by week 4. CONCLUSIONS: Once daily TMC435 given orally was generally safe and well tolerated and demonstrated potent antiviral activity.


Assuntos
Antivirais/administração & dosagem , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Compostos Heterocíclicos com 3 Anéis/administração & dosagem , Inibidores de Proteases/administração & dosagem , RNA Viral/sangue , Sulfonamidas/administração & dosagem , Carga Viral/efeitos dos fármacos , Proteínas não Estruturais Virais/antagonistas & inibidores , Administração Oral , Adulto , Antivirais/efeitos adversos , Antivirais/farmacocinética , DNA Viral/análise , Método Duplo-Cego , Esquema de Medicação , Feminino , Genótipo , Hepacivirus/enzimologia , Hepacivirus/genética , Hepatite C/diagnóstico , Compostos Heterocíclicos com 3 Anéis/efeitos adversos , Compostos Heterocíclicos com 3 Anéis/farmacocinética , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores de Proteases/efeitos adversos , Inibidores de Proteases/farmacocinética , Simeprevir , Sulfonamidas/efeitos adversos , Sulfonamidas/farmacocinética , Fatores de Tempo , Resultado do Tratamento , Proteínas não Estruturais Virais/genética , Adulto Jovem
11.
Hepatology ; 52(5): 1590-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20938912

RESUMO

UNLABELLED: Narlaprevir (SCH 900518) is a potent inhibitor of the hepatitis C virus (HCV) nonstructural protein 3 serine protease that is primarily metabolized by the cytochrome P450-3A4 system. In order to explore the use of ritonavir-based pharmacokinetic enhancement of an HCV protease inhibitor, this study investigated the safety, tolerability, pharmacokinetics, and antiviral activity of narlaprevir (with or without ritonavir) administered as monotherapy and as combination therapy with pegylated interferon-α-2b (PEG-IFN-α-2b) to HCV genotype 1-infected patients. This was a randomized, placebo-controlled, two-period, blinded study in 40 HCV genotype 1-infected patients (naïve and treatment-experienced). In period 1, narlaprevir was administered for 7 days as 800 mg three times daily without ritonavir or 400 mg twice daily with 200 mg ritonavir twice daily. In period 2, after a 4-week washout, the same dose and regimen of narlaprevir was administered in combination with PEG-IFN-α-2b for 14 days. Upon completion of period 2, all patients initiated PEG-IFN-α-2b and ribavirin treatment. A rapid and persistent decline in plasma HCV-RNA was observed in both treatment-experienced and treatment-naïve patients during period 1, with a mean viral load decline of at least 4 log10 in all treatment groups. A high percentage of both treatment-experienced (50%) and treatment-naïve (≥ 60%) patients had undetectable HCV-RNA (< 25 IU/mL) after period 2. Standard of care resulted in sustained virological response (SVR) rates of 38% and 81% in treatment-experienced and treatment-naïve patients, respectively. Narlaprevir (with or without ritonavir) alone or in combination with PEG-IFN-α-2b was safe and well tolerated. CONCLUSION: Narlaprevir administration resulted in a robust HCV-RNA decline and high SVR rates when followed by standard of care in both treatment-experienced and treatment-naïve HCV genotype 1-infected patients.


Assuntos
Antivirais/uso terapêutico , Dipeptídeos/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Ritonavir/uso terapêutico , Sulfonas/uso terapêutico , Adulto , Idoso , Antivirais/administração & dosagem , Ciclopropanos , Dipeptídeos/administração & dosagem , Dipeptídeos/farmacocinética , Esquema de Medicação , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/genética , Hepatite C Crônica/genética , Humanos , Pacientes Internados , Interferon alfa-2 , Leucina/análogos & derivados , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Prolina/análogos & derivados , RNA Viral/sangue , Proteínas Recombinantes , Recidiva , Ritonavir/administração & dosagem , Sulfonas/administração & dosagem , Sulfonas/farmacocinética , Ureia , Adulto Jovem
12.
Scand J Gastroenterol ; 46(11): 1362-8, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21815864

RESUMO

BACKGROUND: The extensive heterogeneity of the hypervariable region-1 (HVR-1) of hepatitis C virus (HCV) evidences the high genetic flexibility of HCV and was shown to be associated with virologic response to interferon-α-based therapies. However, the evolution of HVR-1 heterogeneity during treatment with directly acting antivirals has not been studied. METHODS: Clonal sequence analysis of HVR-1 quasispecies in the serum of patients who were treated with telaprevir (3 × 750 mg/day) alone, telaprevir plus pegylated interferon-α-2a (pegIFN-α-2a), or pegIFN-α-2a plus placebo for 14 days was performed. HVR-1 heterogeneity, expressed as Shannon complexity and Hamming distance, was analyzed with virologic response and with the emergence of variants associated with resistance to telaprevir. RESULTS: HVR-1 heterogeneity at baseline was not associated with response to telaprevir-based therapy (Shannon complexity 0.34 vs. 0.55, p = 0.38; Hamming distance 0.15 vs. 0.23, p = 0.51; for patients with or without viral breakthrough, respectively). No significant changes in HVR-1 complexity were observed from baseline to day 4 of therapy in patients in whom a continued decline in HCV RNA was observed (Shannon complexity = 0.55 vs. 0.51, p = 0.67; Hamming distance = 0.23 vs. 0.25, p = 0.81, respectively). This was similar in patients with viral breakthrough associated with telaprevir-resistant variants (Shannon complexity = 0.34 vs. 0.42, p = 0.68; Hamming distance = 0.15 vs. 0.2, p = 0.50, at baseline and day 4, respectively). CONCLUSIONS: Baseline and on-treatment HVR-1 heterogeneity are not associated with early viral response to telaprevir-based therapy.


Assuntos
Antivirais/farmacologia , Evolução Molecular , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Proteínas Virais/genética , Adulto , Antivirais/uso terapêutico , Farmacorresistência Viral/genética , Quimioterapia Combinada , Feminino , Heterogeneidade Genética/efeitos dos fármacos , Hepacivirus/efeitos dos fármacos , Hepatite C/sangue , Hepatite C/virologia , Humanos , Interferon-alfa/farmacologia , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/farmacologia , Oligopeptídeos/uso terapêutico , Polietilenoglicóis/farmacologia , Polietilenoglicóis/uso terapêutico , RNA Viral/sangue , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Análise de Sequência de RNA , Carga Viral , Adulto Jovem
13.
Biologicals ; 37(2): 71-7, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19231236

RESUMO

A spectrum of blood-borne infectious agents is transmitted through transfusion of infected blood donated by apparently healthy and asymptomatic blood donors. The diversity of infectious agents includes hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency viruses (HIV-1/2), human T-cell lymphotropic viruses (HTLV-I/II), Cytomegalovirus (CMV), Parvovirus B19, West Nile Virus (WNV), Dengue virus, trypanosomiasis, malaria, and variant CJD. Several strategies are implemented to reduce the risk of transmitting these infectious agents by donor exclusion for clinical history of risk factors, screening for the serological markers of infections, and nucleic acid testing (NAT) by viral gene amplification for direct and sensitive detection of the known infectious agents. Consequently, transfusions are safer now than ever before and we have learnt how to mitigate risks of emerging infectious diseases such as West Nile, Chikungunya, and Dengue viruses.


Assuntos
Transmissão de Doença Infecciosa , Reação Transfusional , Infecções por Deltaretrovirus/complicações , Infecções por Deltaretrovirus/epidemiologia , Infecções por Deltaretrovirus/etiologia , Transmissão de Doença Infecciosa/prevenção & controle , Seguimentos , Hepatite B/etiologia , Hepatite B/prevenção & controle , Hepatite B/transmissão , Hepatite B/virologia , Humanos , Fatores de Risco , Segurança , Transplante , Imunologia de Transplantes/fisiologia , Viroses/prevenção & controle , Viroses/transmissão , Viroses/virologia
14.
Liver Int ; 28(1): 39-46, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18031478

RESUMO

BACKGROUND: Development of diabetes mellitus (DM) during or shortly after treatment with interferon alpha (IFN-alpha) in patients with chronic hepatitis C virus (HCV) infection has been reported sporadically. We prospectively screened for DM during and after IFN-alpha therapy for chronic HCV infection. METHODS: Blood glucose levels of patients with chronic HCV infection were routinely assessed at all outpatient visits during and after treatment with pegylated-IFN-alpha (Peg-IFN-alpha) and ribavirin (Riba). RESULTS: Between December 2002 and October 2005, 189 non-diabetic patients were treated with Peg-IFN-alpha/Riba, of whom five developed type 1 DM (2.6%), three type 2 DM (1.6%) and one an indeterminate type of DM. Classical symptoms of DM were present in three patients who developed DM shortly after cessation of Peg-IFN-alpha/Riba. In the other patients, symptoms of DM were either indistinguishable from side effects caused by Peg-IFN-alpha/Riba or absent. CONCLUSION: Our study showed a high incidence of type 1 DM during Peg-IFN-alpha/Riba therapy for chronic HCV infection. Symptoms of DM may be absent or mistaken for Peg-IFN-alpha/Riba-associated side effects. To diagnose DM without delay, we propose routine assessment of blood glucose at all outpatient visits during and after Peg-IFN-alpha/Riba treatment in chronic HCV patients.


Assuntos
Diabetes Mellitus Tipo 1/etiologia , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/efeitos adversos , Polietilenoglicóis/efeitos adversos , Ribavirina/efeitos adversos , Glicemia/análise , Peptídeo C/sangue , Sondas de DNA de HLA , Feminino , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Masculino , Polietilenoglicóis/uso terapêutico , Proteínas Recombinantes , Ribavirina/uso terapêutico
15.
Scand J Gastroenterol ; 43(9): 1122-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18609142

RESUMO

OBJECTIVE: Neopterin is a marker of monocyte/macrophage activity. Alanine aminotransferase (ALAT) is a marker of hepatocyte injury. The aim of this study was to determine changes in neopterin and ALAT levels, as markers of inflammation, in two ancillary studies during two-phase 1b trials of hepatitis C virus (HCV) NS3.4A protease inhibitor telaprevir (VX-950), with or without peginterferon alfa-2a (Peg-IFN). MATERIAL AND METHODS: Fifty-four chronic hepatitis C patients (genotype 1) received placebo or telaprevir, with or without Peg-IFN, for 14 days in two multiple-dose studies. RESULTS: During administration of telaprevir, every patient demonstrated a >2-log decrease in HCV RNA. Mean neopterin and ALAT levels decreased in all four groups receiving telaprevir alone. In contrast, mean neopterin levels increased and ALAT levels decreased in the Peg-IFN plus telaprevir and Peg-IFN plus placebo groups. CONCLUSIONS: These data suggest that treatment of chronic hepatitis C patients with an HCV NS3.4A protease inhibitor ameliorates inflammation. The increase in neopterin levels and the decrease in ALAT levels during administration of Peg-IFN with or without telaprevir are in accordance with earlier observations showing that IFN reduces hepatocyte injury but increases monocyte/macrophage activity. The IFN-mediated immunomodulatory effects appear to remain intact when IFN is combined with telaprevir.


Assuntos
Hepatite C Crônica/sangue , Hepatite C Crônica/tratamento farmacológico , Mediadores da Inflamação/sangue , Interferon-alfa/administração & dosagem , Oligopeptídeos/administração & dosagem , Polietilenoglicóis/administração & dosagem , Adulto , Alanina Transaminase/sangue , Relação Dose-Resposta a Droga , Esquema de Medicação , Quimioterapia Combinada , Feminino , Seguimentos , Hepacivirus/efeitos dos fármacos , Hepacivirus/isolamento & purificação , Hepatite C Crônica/diagnóstico , Humanos , Interferon alfa-2 , Testes de Função Hepática , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Neopterina/sangue , Proteínas Recombinantes , Valores de Referência , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Resultado do Tratamento , Proteínas não Estruturais Virais
16.
Scand J Gastroenterol ; 43(7): 857-69, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18584525

RESUMO

OBJECTIVE: To determine (i) whether early viral kinetics or other markers during a modified treatment regimen are predictors of treatment outcome and (ii) whether fast responders can be treated for 24 weeks, without compromising the sustained virologic response (SVR) rate. MATERIAL AND METHODS: One hundred "difficult-to-treat" chronic hepatitis C patients (46 previous non-responders/relapsers (any genotype), 54 treatment-naive patients genotypes 1 and 4) were treated with triple antiviral induction therapy: amantadine hydrochloride and ribavirin, combined with 6 weeks interferon alfa-2b induction (weeks 1-2: 18 MU/day, weeks 3-4: 9 MU/day, weeks 5-6: 6 MU/day), thereafter combined with weekly peginterferon alfa-2b. Fast responders (>or=3 log(10) HCV RNA decline at week 4) were randomized to 24 or 48 weeks. Slow responders (<3 log(10) HCV RNA decline at week 4) were treated for 48 weeks. Treatment was stopped in patients with detectable HCV RNA at week 24. RESULTS: Thirty-six patients achieved SVR: 28 of 60 fast responders (47%) versus 8 of 32 slow responders (25%, p<0.05). Relapse rates among fast responders treated for 24 or 48 weeks were 27% and 20%, respectively (p=NS). SVR in fast responders was independent of baseline HCV RNA >or= or <600,000 IU/mL. All treatment-naive patients with HCV RNA <5 IU/mL at week 1 or 2 achieved SVR; all treatment-naive patients with HCV RNA >or=5 IU/mL at week 16 became non-SVR. In previous non-responders/relapsers, the predictive value for SVR was 83% if HCV RNA was <5 IU/mL at week 2; all previous non-responders/relapsers with HCV RNA >or=5 IU/mL at week 8 became non-SVR. CONCLUSIONS: With high-dose interferon induction, SVR and non-SVR can be predicted reliably within 16 weeks. Fast responders can be treated for 24 weeks, and SVR is independent of baseline viral load in fast responders.


Assuntos
Antivirais/administração & dosagem , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/administração & dosagem , Carga Viral , Adulto , Idoso , Feminino , Genótipo , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis , RNA Viral/sangue , Proteínas Recombinantes
17.
Antivir Ther ; 12(3): 423-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17591033

RESUMO

BACKGROUND: In chronic hepatitis C patients with an initial virological response (IVR) during antiviral therapy (that is, HCV RNA becomes negative before week 16 of treatment) the significance of reappearing viraemia below the detection limit of PCR is not known. We studied this phenomenon in subsets of patients. METHODS: We assessed HCV RNA at weeks 16 and 20 of therapy by PCR and by more sensitive transcription-mediated amplification (TMA) in 23 patients with breakthrough or relapse and in 34 patients with sustained virological response (SVR). All patients participated in a high-dose-interferon induction study for difficult-to-treat patients. Therapy consisted of amantadine hydrochloride and ribavirin, combined with interferon-alpha2b induction during the first 6 weeks and thereafter combined with weekly pegylated interferon-alpha2b. RESULTS: Among the 57 IVR patients, we detected transient or persistent reappearance of low levels of HCV RNA in 10 of the 23 (43%) patients with eventual breakthrough or relapse; but in none of the 34 SVR patients. In 5 of 10 patients reappearing HCV RNA was only detectable by TMA. CONCLUSION: Reappearance of low levels of HCV RNA in patients with IVR predicts treatment failure.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/isolamento & purificação , Hepatite C Crônica/tratamento farmacológico , Técnicas de Amplificação de Ácido Nucleico , Adulto , Idoso , Biomarcadores , Quimioterapia Combinada , Feminino , Hepacivirus/genética , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes , RNA Viral/sangue , Sensibilidade e Especificidade , Especificidade da Espécie , Falha de Tratamento , Viremia/diagnóstico
18.
Ultrasound Med Biol ; 33(9): 1362-7, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17467151

RESUMO

Previous studies have shown that the total perihepatic lymph node (PLN) volume is (1) associated with the extent of inflammatory activity in the liver and (2) changes according to the antiviral response in patients receiving interferon-based therapy for chronic hepatitis C (HCV) infection. The aim of this prospective pilot study was to examine whether the total PLN volume similarly changes in patients receiving antiviral monotherapy with the protease inhibitor telaprevir (VX-950). The present study was conducted in a subgroup of 19 patients with chronic hepatitis C genotype-1 infection treated with the protease inhibitor telaprevir (VX-950) or placebo in a phase Ib clinical trial. The total perihepatic lymph node volume was assessed using sonography before the initiation of antiviral therapy, at the end of 14 d of treatment, and at follow-up. Treatment with telaprevir resulted in a significant reduction of plasma HCV-RNA in all patients at the end of 14 d of treatment. In patients receiving telaprevir, the total PLN volume decreased significantly at the end of 14 d of treatment compared with pretreatment volume (1.26 mL to 0.76 mL, p=0.01). In contrast, no significant difference was seen in patients receiving placebo (1.00 mL to 1.06 mL, p=0.26). These results suggest that the perihepatic lymph node volume can be used as an indicator for viral and histologic response not only as previously reported in patients receiving interferon-based therapy, but also in patients receiving therapy with direct antivirals.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/diagnóstico por imagem , Fígado/diagnóstico por imagem , Linfonodos/diagnóstico por imagem , Oligopeptídeos/uso terapêutico , Inibidores de Proteases/uso terapêutico , Adulto , Feminino , Hepatite C Crônica/sangue , Hepatite C Crônica/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , RNA Viral/sangue , Ultrassonografia , Viremia/sangue , Viremia/diagnóstico por imagem
20.
J Microbiol Methods ; 61(2): 285-8, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15722157

RESUMO

Due to contamination of DNA extraction reagents, false-positive results can occur when applying broad-range real-time PCR based on bacterial 16S rDNA. Filtration of the nucleic acid extraction kit reagents with GenElute Maxiprep binding columns was effective in removing this reagent-derived contaminating DNA while the sensitivity of the assay was maintained.


Assuntos
DNA Bacteriano/isolamento & purificação , Kit de Reagentes para Diagnóstico/normas , Plaquetas/microbiologia , Reações Falso-Positivas , Humanos , RNA Ribossômico 16S/análise
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