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1.
Hepatology ; 62(4): 1013-23, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26118427

RESUMO

UNLABELLED: Alisporivir is a cyclophilin inhibitor with pan-genotypic anti-hepatitis C virus (HCV) activity and a high barrier to viral resistance. The VITAL-1 study assessed alisporivir as interferon (IFN)-free therapy in treatment-naïve patients infected with HCV genotype 2 or 3. Three hundred forty patients without cirrhosis were randomized to: arm 1, alisporivir (ALV) 1,000 mg once-daily (QD); arm 2, ALV 600 mg QD and ribavirin (RBV); arm 3, ALV 800 mg QD and RBV; arm 4, ALV 600 mg QD and pegylated IFN (Peg-IFN); or arm 5, Peg-IFN and RBV. Patients receiving IFN-free ALV regimens who achieved rapid virological response (RVR) continued the same treatment throughout, whereas those with detectable HCV RNA at week 4 received ALV, RBV, and Peg-IFN from weeks 6 to 24. Overall, 300 patients received ALV-based regimens. In arm 1 to arm 4, the intent-to-treat rates of sustained virological response (SVR) 24 weeks after treatment (SVR24) were from 80% to 85%, compared with 58% (n = 23 of 40) with Peg-IFN/RBV. Per-protocol analysis showed higher SVR24 rates in patients who received ALV/RBV, IFN-free after RVR (92%; n = 56 of 61) than with ALV alone after RVR (72%; n = 13 of 18) or with Peg-IFN/RBV (70%; n = 23 of 33). Both RVRs and SVRs to ALV IFN-free regimens were numerically higher in genotype 3- than in genotype 2-infected patients. Viral breakthrough was infrequent (3%; n = 7 of 258). IFN-free ALV treatment showed markedly better safety/tolerability than IFN-containing regimens. CONCLUSIONS: ALV plus RBV represents an effective IFN-free option for a proportion of patients with HCV genotype 2 or 3 infections, with high SVR rates for patients with early viral clearance. Further investigations of ALV in IFN-free combination regimens with direct-acting antiviral drugs deserve exploration in future trials.


Assuntos
Antivirais/administração & dosagem , Ciclosporina/administração & dosagem , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/administração & dosagem , Polietilenoglicóis/administração & dosagem , Ribavirina/administração & dosagem , Adulto , Feminino , Genótipo , Hepacivirus/classificação , Hepacivirus/genética , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/administração & dosagem
2.
J Hepatol ; 62(1): 41-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25152207

RESUMO

BACKGROUND & AIMS: This study investigated the antiviral efficacy and safety of telbivudine in combination with pegylated interferon (PegIFN) alpha-2a in chronic hepatitis B (CHB) patients. METHODS: This was a randomized, open-label, multicentre study, in treatment-naïve patients with HBeAg-positive CHB, comparing the efficacy and safety of telbivudine in combination with PegIFN alpha-2a with telbivudine monotherapy and PegIFN alpha-2a monotherapy. The study was terminated early due to increased rates of peripheral neuropathy in the combination-therapy group. RESULTS: Of the 159 patients randomized (from 300 planned) 50 were assigned to combination therapy, 55 to telbivudine, 54 to PegIFN, and 110 (18, 49, and 43, respectively) reached week 24. Peripheral neuropathy occurred in 7/50, 1/54, and 0/54 patients in the three groups of safety populations, respectively. No relationship between the occurrence of peripheral neuropathy and other variables (e.g., pharmacokinetic data, treatment efficacy, ALT levels, creatine kinase elevations) were observed. At week 24, undetectable HBV DNA (<300 copies/ml) was achieved by 71% (12/17), 35% (17/48), and 7% (3/42) of patients, with available data receiving combination therapy, telbivudine monotherapy and PegIFN monotherapy, respectively (p = 0.022 for combination therapy vs. telbivudine; p<0.0001 for combination therapy vs. PegIFN). CONCLUSIONS: Combination therapy carried an increased risk of peripheral neuropathy. Despite the rapid and profound reductions in HBV DNA levels, combination therapy with telbivudine and PegIFN should not be used.


Assuntos
Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/efeitos adversos , Doenças do Sistema Nervoso Periférico/etiologia , Polietilenoglicóis/efeitos adversos , Timidina/análogos & derivados , Adulto , Antivirais/efeitos adversos , Antivirais/farmacocinética , DNA Viral/análise , Portadores de Fármacos , Quimioterapia Combinada , Feminino , Saúde Global , Antígenos E da Hepatite B/imunologia , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Hepatite B Crônica/metabolismo , Hepatite B Crônica/virologia , Humanos , Incidência , Interferon-alfa/farmacocinética , Masculino , Doenças do Sistema Nervoso Periférico/diagnóstico , Doenças do Sistema Nervoso Periférico/epidemiologia , Polietilenoglicóis/farmacocinética , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/farmacocinética , Telbivudina , Timidina/efeitos adversos , Timidina/farmacocinética
3.
Clin Immunol ; 131(3): 415-25, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19303818

RESUMO

Plasma and cellular HCV RNA and core antigen were tested in monocyte-derived DC (MDDC) from chronic hepatitis C patients undergoing treatment with peg-interferon alpha2b/ribavirin. DC allostimulatory capacity, HCV-specific T-cell reactivity and IL-12 production were measured at baseline and treatment week (TW)12. Using DC and autologous CD4(+)T-cells, obtained at baseline and TW12, we performed cross-over experiments to determine the relative role of DC and/or T-cells for impaired immune reactivity to HCV. HCV RNA and HCV core plasma levels had an impact on DC phenotype and allostimulatory capacity. In contrast, HCV genome/core protein, although detectable in DC from some patients had no effect on DC function. Antiviral immunity at TW12 was not improved in patients who remained HCV RNA positive, while early viraemia clearance (TW12) improved antiviral responses. The cross-over experiment revealed that changes in DC, rather than CD4(+)T cells have a major role for enhanced anti-HCV responses.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Células Dendríticas/imunologia , Hepatite C Crônica/tratamento farmacológico , Viremia/tratamento farmacológico , Adulto , Antígenos Virais/sangue , Antivirais/uso terapêutico , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/virologia , Células Cultivadas , Células Dendríticas/metabolismo , Células Dendríticas/virologia , Feminino , Hepacivirus/isolamento & purificação , Hepatite C Crônica/imunologia , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Interleucina-12/biossíntese , Interleucina-12/imunologia , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis , RNA Viral/sangue , Proteínas Recombinantes , Ribavirina/uso terapêutico
4.
J Infect Dis ; 198(10): 1448-56, 2008 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-18928375

RESUMO

BACKGROUND: Hepatitis C virus (HCV) genotype is an important determinant of virological response to antiviral therapies. Currently, there are no data available on the molecular epidemiology and interferon susceptibility of the natural intergenotypic recombinant RF1_2k/1b (RF1) strain. METHODS: Genotyping and RF1-PCR screening were performed on samples from 604 HCV RNA-positive individuals from 7 countries. uPA/SCID mice carrying human hepatocytes (chimeric mice) were infected with the RF1_2k/1b strain, and the susceptibility of the strain to interferon and ribavirin was compared with the susceptibilities of 2 different strains of genotype B, used as references. RESULTS: Six new RF1 cases were identified in this study; 5 (2%) of 281 in Russia and 1 (1%) of 90 in Uzbekistan. Phylogenetic analyses based on Core/E1 and NS5b indicated that all RF1 representatives share a common evolutionary ancestor. Infection with RF1 was established in chimeric mice. Reduction of RF1 viral load was observed in response to 3 injections of 3 microg/kg pegylated-interferon alpha-2a alone or in combination with 50 mg/kg of ribavirin (0.5 or 1.4 log-copies/mL). CONCLUSIONS: All identified RF1-type strains appear to be introduced from a single source, suggesting that intergenotypic recombination in HCV is sporadic and not associated with cocirculation of different genotypes in a population. The RF1 strain in this study was responsive to interferon in vivo.


Assuntos
Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Interferon-alfa/farmacologia , Polietilenoglicóis/farmacologia , Recombinação Genética , Adulto , Animais , Antivirais/uso terapêutico , Evolução Molecular , Feminino , Genótipo , Hepacivirus/classificação , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Hepatite C/epidemiologia , Hepatite C/virologia , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Masculino , Camundongos , Pessoa de Meia-Idade , Epidemiologia Molecular , Dados de Sequência Molecular , Polietilenoglicóis/uso terapêutico , Proteínas Recombinantes , Ribavirina/uso terapêutico , Adulto Jovem
5.
J Infect Dis ; 196(7): 998-1005, 2007 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-17763320

RESUMO

UNLABELLED: BACKGROUND. Hepatitis C virus (HCV) genotype 1 is the most prevalent genotype in Western countries, and treatment with pegylated interferon (pegIFN) plus ribavirin fails in 50%-60% of patients. Genetic variability within the NS5A dsRNA-dependent protein kinase binding domain (PKRbd) of HCV-1b has been associated with responsiveness to IFN- alpha . Little is known about NS5A sequences of HCV-1a. We investigated whether genetic variability of HCV-1a NS5A correlates with the early HCV kinetics during treatment. METHODS: Twenty-four treatment-naive, HCV-1a-infected patients were treated with standard doses of pegIFN- alpha 2a plus ribavirin. HCV viremia was quantitated at days 0, 1, 2, and 3 and weeks 1, 2, 4, 8, and 12 of treatment. According to HCV kinetics, patients were classified as early rapid responders, early moderate responders, or early slow responders. The full-length HCV NS5A was sequenced at baseline and at week 1. RESULTS: At baseline, variability of the NS5A C terminus (concentrated in the PKRbd) is associated with interferon efficacy but not with the second phase of the early viral decline that has been associated with a sustained virologic response. Comparisons between baseline and week-1 full-length sequences did not show significant increases in mutations. CONCLUSIONS: Genetic variability of HCV-1a NS5A does not predict responsiveness to IFN- alpha . Differences in early kinetics during combination therapy are not due to selection of IFN-resistant HCV strains.


Assuntos
Antivirais , Variação Genética , Hepacivirus/efeitos dos fármacos , Interferon-alfa , Polietilenoglicóis , Ribavirina , Proteínas não Estruturais Virais/genética , Sequência de Aminoácidos , Antivirais/administração & dosagem , Antivirais/farmacologia , Antivirais/uso terapêutico , Farmacorresistência Viral , Quimioterapia Combinada , Genótipo , Hepacivirus/classificação , Hepacivirus/genética , Humanos , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Interferon-alfa/farmacologia , Interferon-alfa/uso terapêutico , Cinética , Modelos Biológicos , Dados de Sequência Molecular , Filogenia , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/farmacologia , Polietilenoglicóis/uso terapêutico , RNA Viral/sangue , Proteínas Recombinantes , Ribavirina/administração & dosagem , Ribavirina/farmacologia , Ribavirina/uso terapêutico , Alinhamento de Sequência , Análise de Sequência de DNA , Resultado do Tratamento , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/metabolismo
6.
Clin Gastroenterol Hepatol ; 4(2): 233-48, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16469685

RESUMO

BACKGROUND & AIMS: Treatment of chronic hepatitis B (CHB) involves a number of complex and controversial issues. Expert opinions may differ from those of practicing hepatologists and gastroenterologists. We aimed to explore this issue further after a critical review of the literature. METHODS: A panel of 14 international experts graded the strength of evidence for 16 statements addressing 3 content areas: patient selection, therapeutic end points, and treatment options. Available data relating to the statements were reviewed critically in 3 small work groups. After discussion of each statement with the entire panel, the experts voted anonymously to accept or reject statements based on the strength of evidence and their experience. A total of 241 members of the American Association for the Study of Liver Diseases (AASLD) responded to the same statements and their responses were compared with those of the experts. A discordant response was defined as a difference of more than 20% in any of the 5 graded levels of response (accept or reject) between the 2 groups. RESULTS: With the exception of 2 statements, the experts' responses were relatively uniform. However, the responses of the AASLD members were discordant from the experts in 12 statements, spanning all 3 content areas. CONCLUSIONS: Several areas of disagreement on the management of CHB exist between experts and AASLD members. Our results indicate a potential knowledge gap among practicing hepatologists. Better educational efforts are needed to meet the challenge of managing this complex disorder in which even expert opinion occasionally may disagree.


Assuntos
Hepatite B Crônica/terapia , Adenina/administração & dosagem , Adenina/análogos & derivados , Alanina Transaminase/sangue , Antivirais/administração & dosagem , Antivirais/uso terapêutico , Biópsia , Competência Clínica , DNA Viral/análise , Progressão da Doença , Quimioterapia Combinada , Determinação de Ponto Final , Antígenos E da Hepatite B/análise , Vírus da Hepatite B/genética , Humanos , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Interferon-alfa/uso terapêutico , Interferons/uso terapêutico , Lamivudina/administração & dosagem , Fígado/patologia , Organofosfonatos/administração & dosagem , Seleção de Pacientes , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/uso terapêutico , Proteínas Recombinantes , Sociedades Médicas , Replicação Viral
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