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1.
J Viral Hepat ; 24(10): 823-831, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28295923

RESUMO

Portal hypertension is a predictor of liver-related clinical events and mortality in patients with hepatitis C and cirrhosis. The effect of interferon-free hepatitis C treatment on portal pressure is unknown. Fifty patients with Child-Pugh-Turcotte (CPT) A and B cirrhosis and portal hypertension (hepatic venous pressure gradient [HVPG] >6 mm Hg) were randomized to receive 48 weeks of open-label sofosbuvir plus ribavirin at Day 1 or after a 24-week observation period. The primary endpoint was sustained virologic response 12 weeks after therapy (SVR12) in patients who received ≥1 dose of treatment. Secondary endpoints included changes in HVPG, laboratory parameters, and MELD and CPT scores. A subset of patients was followed 48 weeks posttreatment to determine late changes in HVPG. SVR12 occurred in 72% of patients (33/46). In the 37 patients with paired HVPG measurements at baseline and the end of treatment, mean HVPG decreased by -1.0 (SD 3.97) mm Hg. Nine patients (24%) had ≥20% decreases in HVPG during treatment. Among 39 patients with pretreatment HVPG ≥12 mm Hg, 27 (69%) achieved SVR12. Four of the 33 (12%) patients with baseline HVPG ≥12 mm Hg had HVPG <12 mm Hg at the end of treatment. Of nine patients with pretreatment HVPG ≥12 mm Hg who achieved SVR12 and completed 48 weeks of follow-up, eight (89%) had a ≥20% reduction in HVPG, and three reduced their pressure to <12 mm Hg. Patients with chronic HCV and compensated or decompensated cirrhosis who achieve SVR can have clinically meaningful reductions in HVPG at long-term follow-up. (EudraCT 2012-002457-29).


Assuntos
Hepacivirus , Veias Hepáticas/fisiopatologia , Hepatite C/complicações , Hepatite C/virologia , Hipertensão Portal/etiologia , Hipertensão Portal/fisiopatologia , Cirrose Hepática/complicações , Cirrose Hepática/etiologia , Pressão na Veia Porta , Adulto , Idoso , Antivirais/uso terapêutico , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral , Resposta Viral Sustentada , Fatores de Tempo , Carga Viral
2.
Haemophilia ; 23(2): 198-206, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28124511

RESUMO

INTRODUCTION: Chronic hepatitis C virus (HCV) infection is prevalent among patients with inherited bleeding disorders and is a leading cause of mortality in those with haemophilia. AIM: We evaluated the efficacy and safety of ledipasvir-sofosbuvir and sofosbuvir plus ribavirin in patients with chronic HCV genotype 1-4 infection and an inherited bleeding disorder. METHODS: Ledipasvir-sofosbuvir was administered for 12 weeks to patients with genotype 1 or 4 infection and for 12 or 24 weeks to treatment-experienced cirrhotic patients with genotype 1 infection. Patients with genotype 2 and 3 infection received sofosbuvir plus ribavirin for 12 and 24 weeks respectively. RESULTS: The majority of the 120 treated patients had a severe bleeding disorder (55%); overall, 65% of patients had haemophilia A and 26% of patients had haemophilia B; 22% were HIV coinfected. Sustained virologic response at 12 weeks posttreatment was 99% (98/99) in patients with genotype 1 or 4 infection; 100% (5/5) in treatment-experienced cirrhotic patients with genotype 1 infection; 100% (10/10) in patients with genotype 2 infection; and 83% (5/6) in patients with genotype 3 infection. There were no treatment discontinuations due to adverse events (AEs). The most frequent non-bleeding AEs were fatigue, headache, diarrhoea, nausea and insomnia. Bleeding AEs occurred in 22 patients, of which all but one were considered unrelated to treatment. CONCLUSION: Treatment with ledipasvir-sofosbuvir for patients with HCV genotype 1 or 4 infection or sofosbuvir plus ribavirin for patients with genotype 2 or 3 infection was highly effective and well tolerated among those with inherited bleeding disorders.


Assuntos
Antivirais/uso terapêutico , Benzimidazóis/uso terapêutico , Fluorenos/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Ribavirina/uso terapêutico , Sofosbuvir/uso terapêutico , Adulto , Idoso , Antivirais/administração & dosagem , Benzimidazóis/administração & dosagem , Combinação de Medicamentos , Feminino , Fluorenos/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Ribavirina/administração & dosagem , Sofosbuvir/administração & dosagem , Resultado do Tratamento , Adulto Jovem
3.
J Viral Hepat ; 23(8): 644-51, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27004425

RESUMO

GS-9190 is a NS5B non-nucleoside analogue with demonstrated effectiveness in a Phase 1 monotherapy study and in combination with other DAAs for treatment of chronic HCV infection. Here, the resistance profile of GS-9190 monotherapy in a Phase 1b study was investigated. Resistance analysis was performed by population sequencing and allele-specific PCR (AS-PCR) for Y448H with an assay cut-off of 0.5%. Phenotypic susceptibility analyses were performed on patient isolates as well as site-directed mutagenesis of mutations selected during monotherapy. No resistance-associated variants were observed in patients before or after receiving single doses of GS-9190 by population sequencing. In contrast, in patients who received GS-9190 for 8 days, mutations Y448H and Y452H in NS5B were observed by population sequencing in 21/36 (58%) and 2/36 (5.6%) patients, respectively, at Day 8 or Day 14. Among the remaining 15 patients who had no detectable Y448H at Day 8 or Day 14 by population sequencing, low frequencies of Y448H ranging from 1.3 to 9.7% were detected in 14 of 15 patients by AS-PCR. By AS-PCR, Y448H remained detectable at reduced frequency in the majority of patients analysed through 4-6 months of follow-up. Chimeric HCV replicons constructed with the NS5B sequence from patients with Y448H and Y448H + Y452H/Y demonstrated 27-fold and 78.5-fold reduced susceptibility to GS-9190. In conclusion, Y448H was rapidly selected in the majority of patients receiving multiple doses of GS-9190 as monotherapy, despite undetectable levels in pretreatment samples. Y448H confers reduced susceptibility to GS-9190 and other NNIs and persisted in most patients for months post-treatment.


Assuntos
Antivirais/administração & dosagem , Farmacorresistência Viral , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Purinas/administração & dosagem , Piridazinas/administração & dosagem , Adulto , Método Duplo-Cego , Feminino , Genótipo , Técnicas de Genotipagem , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Recombinação Genética , Seleção Genética , Resultado do Tratamento
4.
J Viral Hepat ; 23(7): 496-505, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26840694

RESUMO

Chronic hepatitis C virus (HCV) infection can now be treated with oral directly acting antiviral agents, either with or without ribavirin (RBV). Virologic relapse after treatment can occur, and in some studies was more common in cirrhotic subjects. We previously observed changes in hepatic immunity during interferon (IFN)-free therapy that correlated with favourable outcome in subjects with early liver disease. Here, we compared changes in endogenous IFN pathways during IFN-free, RBV-free therapy between cirrhotic and noncirrhotic subjects. mRNA and microRNA (miRNA) expression analyses were performed on paired pre- and post-treatment liver biopsies from genotype-1 HCV subjects treated with sofosbuvir/ledipasvir (SOF/LDV) for 12 weeks (n = 4, 3 cirrhotics) or SOF/LDV combined with GS-9669 or GS-9451 for 6 weeks (n = 6, 0 cirrhotics). Nine of ten subjects achieved a sustained virologic response (SVR), while one noncirrhotic subject relapsed. Hepatic IFN-stimulated gene expression decreased with treatment in the liver of all subjects, with no observable impact of cirrhosis. Hepatic gene expression of type III IFNs (IFNL1, IFNL3, IFNL4-ΔG) similarly decreased with treatment, while IFNA2 expression, undetectable in all subjects pretreatment, was detected post-treatment in three subjects who achieved a SVR. Only the subject who relapsed had detectable IFNL4-ΔG expression in post-treatment liver. Other IFNs had no change in gene expression (IFNG, IFNB1, IFNA5) or could not be detected. Although expression of multiple hepatic miRNAs changed with treatment, many miRNAs previously implicated in HCV replication and IFN signalling had unchanged expression. In conclusion, favourable treatment outcome during IFN-free HCV therapy is associated with changes in the host IFN response regardless of cirrhosis.


Assuntos
Antivirais/uso terapêutico , Perfilação da Expressão Gênica , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/patologia , Interferons/análise , Resposta Viral Sustentada , Feminino , Hepatite C Crônica/diagnóstico , Humanos , Masculino , MicroRNAs/análise , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , RNA Mensageiro/análise , Análise de Sequência de DNA , Resultado do Tratamento
5.
Haemophilia ; 22(2): 214-217, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26315711

RESUMO

AIM: People with inherited bleeding disorders have been disproportionally affected by HCV. We assessed the fixed-dose combination of the NS5A inhibitor ledipasvir (LDV) with the NS5B polymerase inhibitor sofosbuvir (SOF) with ribavirin (RBV) in patients with genotype 1 HCV and inherited bleeding disorders. METHODS: To be eligible, patients had to be over 18 years of age and have an inherited bleeding disorder. HCV treatment-naïve and -experienced patients could enrol. All patients received LDV 90 mg per SOF 400 mg once daily and weight-based RBV in a divided dose for 12 weeks. The primary efficacy endpoint was sustained virologic response (SVR), defined as HCV RNA below the limit of detection (15 IU mL-1 ) 12 weeks after the end of treatment (SVR12). RESULTS: Of the 14 patients enrolled, 8 (57%) had haemophilia A, 3 (21%) had haemophilia B and 2 (14%) had von Willebrand disease, and 1 (7%) had factor XIII deficiency. All 14 patients (100%, 95% CI: 77-100%) achieved SVR12. Treatment was well tolerated: all patients completed therapy, with mostly mild adverse events. No specific safety concerns associated with the patient's underlying bleeding disorders were noted. CONCLUSION: These results appear to suggest that people with HCV and inherited bleeding disorders can be safely and effectively treated with 12 weeks of LDV/SOF plus RBV.

6.
Am J Transplant ; 12(3): 737-44, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22300408

RESUMO

IL28B polymorphisms are strongly associated with response to treatment for HCV infection. IL28B acts on interferon-stimulated genes via the JAK-STAT pathway, which has been implicated in development of insulin resistance. We investigated whether IL28B polymorphisms are associated with posttransplant diabetes mellitus (DM). Consecutive HCV patients who underwent liver transplantation between 1-1995 and 1-2011 were studied. Genotyping of the polymorphism rs12979860 was performed on DNA collected from donors and recipients. Posttransplant DM was screened for by fasting blood glucoses every 1-3 months. Of 221 included patients, 69 developed posttransplant DM (31%). Twenty-two patients with recipient IL28B genotype TT (48%), 25 with IL28B genotype CT (25%) and 22 with IL28B genotype CC (29%) developed posttransplant DM. TT genotype was statistically significantly associated with posttransplant DM over time (log rank p = 0.012 for TT vs. CT and p = 0.045 for TT vs. CC). Multivariate Cox regression analysis correcting for donor age, body mass index, baseline serum glucose, baseline serum cholesterol, recipient age and treated rejection, showed that recipient IL28B genotype TT was independently associated with posttransplant DM (hazard ratio 2.51; 95% confidence interval 1.17-5.40; p = 0.011). We conclude that the risk of developing posttransplant DM is significantly increased in recipients carrying the TT polymorphism of the IL28B gene.


Assuntos
Diabetes Mellitus/etiologia , Hepatite C Crônica/complicações , Interleucinas/genética , Transplante de Fígado/efeitos adversos , Polimorfismo Genético/genética , Complicações Pós-Operatórias , Adulto , Diabetes Mellitus/diagnóstico , Feminino , Seguimentos , Hepacivirus/patogenicidade , Hepatite C Crônica/genética , Hepatite C Crônica/cirurgia , Humanos , Interferon gama/metabolismo , Interferons , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , RNA Viral/genética
7.
J Viral Hepat ; 19(5): 332-40, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22497812

RESUMO

Low-density lipoprotein cholesterol (LDL-C) levels and interleukin 28B (IL28B) polymorphism are associated with sustained viral response (SVR) to peginterferon/ribavirin (pegIFN/RBV) for chronic hepatitis C (CHC) infection. IL28B has been linked with LDL-C levels using a candidate gene approach, but it is not known whether other genetic variants are associated with LDL-C, nor how these factors definitively affect SVR. We assessed genetic predictors of serum lipid and triglyceride levels in 1604 patients with genotype 1 (G1) chronic hepatitis C virus (HCV) infection by genome-wide association study and developed multivariable predictive models of SVR. IL28B polymorphisms were the only common genetic variants associated with pretreatment LDL-C level in Caucasians (rs12980275, P = 4.7 × 10(-17), poor response IL28B variants associated with lower LDL-C). The association was dependent on HCV infection, IL28B genotype was no longer associated with LDL-C in SVR patients after treatment, while the association remained significant in non-SVR patients (P < 0.001). LDL-C was significantly associated with SVR for heterozygous IL28B genotype patients (P < 0.001) but not for homozygous genotypes. SVR modelling suggested that IL28B heterozygotes with LDL-C > 130 mg/dL and HCV RNA ≤600 000 IU/mL may anticipate cure rates >80%, while the absence of these two criteria was associated with an SVR rate of <35%. IL28B polymorphisms are the only common genetic variants associated with pretreatment LDL-C in G1-HCV. LDL-C remains significantly associated with SVR for heterozygous IL28B genotype patients, where LDL-C and HCV RNA burden may identify those patients with high or low likelihood of cure with pegIFN/RBV therapy.


Assuntos
Antivirais/administração & dosagem , LDL-Colesterol/sangue , Hepacivirus/classificação , Hepatite C Crônica/tratamento farmacológico , Interferons/administração & dosagem , Interleucinas/genética , Polimorfismo Genético , Adulto , Feminino , Estudos de Associação Genética , Genótipo , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Ribavirina/administração & dosagem , Resultado do Tratamento , Carga Viral
8.
J Viral Hepat ; 18(8): 571-9, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20642483

RESUMO

Low levels of serum lipids were reported in subjects chronically infected with the hepatitis C virus (HCV) and correlated with poorer clinical outcomes. Whether HCV 'hypo-lipidemia' is constant across age, sex and race has not been systematically explored. We therefore investigated the association between HCV infection and serum lipid levels in two independent National Health and Nutrition Examination Survey (NHANES) cohorts. HCV antibody status and serum lipid levels were obtained from 14 369 adults from NHANES 1999-2006 and 12 261 from NHANES III (enrolled in 1988-1994). In multivariable models, the prevalence of HCV-associated hypo-low density lipoprotein-cholesterol was highest among women >50 years of age in both NHANES 1999-2006 (OR: 10.51, 95% CI: 2.86, 38.62) and III (OR: 24.21, 95% CI: 6.17, 94.92), but among women <50 years of age, the odds ratios were 3.01 (95% CI: 1.00, 9.04) for NHANES 1999-2006 and 0.52 (95% CI: 0.14, 1.88) for III, respectively. HCV by age interaction among women was significant in both cohorts (P < 0.001 and P = 0.004, respectively). Among men, the odds ratios of HCV-associated hypo-LDL-cholesterol were 2.74 (95% CI: 1.55, 4.85) in NHANES 1999-2006 and 3.84 (95% CI: 1.66, 8.88) in III, respectively, with no significant age effects. Similar patterns were observed for total-cholesterol, but no significantly discernable patterns for high density lipoprotein-cholesterol and triglycerides. Results show that HCV infection is associated with lower total- and LDL-cholesterol in two US population-based cohorts, and this relationship varies significantly by age and sex, suggesting a possible influence of sex hormones on host lipid response to HCV infection.


Assuntos
Hepacivirus/patogenicidade , Hepatite C Crônica/sangue , Lipídeos/sangue , Inquéritos Nutricionais/estatística & dados numéricos , Adulto , Fatores Etários , Alanina Transaminase/sangue , Índice de Massa Corporal , Etnicidade , Feminino , Anticorpos Anti-Hepatite C/sangue , Hepatite C Crônica/epidemiologia , Hepatite C Crônica/virologia , Humanos , Hiperlipidemias/sangue , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prevalência , Fatores Sexuais , Estados Unidos/epidemiologia
9.
J Viral Hepat ; 18(5): 331-7, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-20367801

RESUMO

HMG CoA reductase inhibition suppresses in vitro HCV replication through depletion of cellular sterol proteins such as geranylgeraniol. Our aims were to prospectively evaluate the changes in serum and lipid fraction HCV RNA with Rosuvastatin in non-responder (NR) patients with CHC. A total of 11 patients with CHC genotype-1 received Rosuvastatin at 20 mg qd (weeks 0-4), 40 mg qd (weeks 5-12), with 4 week follow up. Lipid fractions were separated by a sucrose density gradient ultracentrifugation, HCV RNA determined at wks 0, 2, 4, 8, 12, 16 in serum, and in selected very low- (VLDF) to high-density (HDF) lipid fractions. A reduction in LDL and total cholesterol (TC) was not accompanied by significant decline in HCV RNA. At baseline, there was an inverse correlation between HDL and HCV RNA (ρ = -0.45, P = 0.036). At 20 mg, there was correlation between change (Δ) in TG and Δ HCV RNA (ρ = 0.75, P = 0.007), Δ ALT and Δ TC (ρ = -0.64, P = 0.03) and Δ LDL (ρ = -0.67, P = 0.02). At 40 mg, Δ TG maintained a positive correlation with Δ HCV RNA (ρ = 0.65, P = 0.03). There was a group difference for HCV RNA in relation to lipid fractions (P = 0.04) but not study time intervals (P = 0.17); mean log HCV RNA was greater in VLDF compared to HDF (5.81 ± 0.59 vs 5.06 ± 0.67, P = 0.0002) with no other differences to study time intervals (P = 0.099). Short-term Rosuvastatin monotherapy is not associated with significant changes in serum or lipid fraction HCV RNA in NR patients. HCV co-localizes with the lowest density lipid fractions in serum.


Assuntos
Fluorbenzenos/administração & dosagem , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Hidroximetilglutaril-CoA Redutases/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Pirimidinas/administração & dosagem , Sulfonamidas/administração & dosagem , Estudos de Coortes , Feminino , Fluorbenzenos/farmacologia , Fluorbenzenos/uso terapêutico , Seguimentos , Hepacivirus/patogenicidade , Hepatite C Crônica/virologia , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , RNA Viral/sangue , Rosuvastatina Cálcica , Estatística como Assunto , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico
10.
J Viral Hepat ; 16(6): 377-87, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19472445

RESUMO

As health care providers, we find ourselves on the verge of a new era in the treatment of chronic hepatitis C virus (HCV) infection. A number of directly acting antiviral agents are now in the latter stages of clinical development. The more promising candidates include direct inhibitors of the HCV nonstructural 3 protease, as well as both nucleoside and non-nucleoside inhibitors of the NS5B RNA-dependent RNA polymerase. Although these agents have demonstrated potent antiviral effect, monotherapy has been complicated by rapid virological breakthrough due to the selection of drug-resistant mutants. As for HIV and HBV, combination therapy will therefore be necessary. This brief review summarizes the current literature concerning resistance and directly acting antiviral agents, and identifies key challenges facing this emerging field.


Assuntos
Antivirais/farmacologia , Antivirais/uso terapêutico , Farmacorresistência Viral , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Quimioterapia Combinada , Humanos
11.
J Viral Hepat ; 16(3): 178-86, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19175870

RESUMO

SUMMARY: Noninvasive markers that accurately follow changes in fibrosis may provide alternatives to liver biopsy for assessment of histological endpoints of antiviral therapy in chronic hepatitis C (CHC). This study compared two commercially available serum marker panels (HCV FibroSURE and FIBROSpect II) during interferon-based therapy. Ninety-five interferon-naïve patients with genotype 1 CHC were enrolled in a phase 2b, active-controlled study of albinterferon alfa-2b/ribavirin for 48 weeks. Proprietary and simple biochemical marker panels were independently evaluated in serum before and during the study. Baseline liver biopsies were evaluated for METAVIR fibrosis by a single pathologist. Index scores were obtained for HCV FibroSURE (n = 84) and FIBROSpect II (n = 95); mean biopsy length: 17.8 +/- 8.0 mm. For detecting fibrosis stages 2-4 (prevalence 23% [22/95] and 21% [18/84]), HCV FibroSURE and FIBROSpect II indicated high sensitivity (1.00 and 0.95, respectively), lower but comparable specificity (0.61 and 0.66, respectively), and a good area under the receiver operating characteristic curve (0.89 and 0.90, respectively). Simple indices had high indeterminate rates (31-40%) at baseline. Patients with a sustained virological response had lower baseline scores than nonresponders, and reduced median percent changes in index scores for HCV FibroSURE (-20.0%vs 2.9%; P = 0.14) and FIBROS Spect II (-6.8%vs 18.4%; P = 0.05). The panels demonstrated comparable performance characteristics for differentiating mild from moderate-severe stage disease in CHC. Lower index scores at baseline that continue to decline likely reflect reduced fibrogenesis activity in patients with successful antiviral responses to therapy.


Assuntos
Albuminas , Antivirais , Biomarcadores/análise , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/fisiopatologia , Interferon-alfa , Cirrose Hepática/fisiopatologia , Kit de Reagentes para Diagnóstico , Ribavirina , Adulto , Albuminas/administração & dosagem , Albuminas/uso terapêutico , Antivirais/administração & dosagem , Antivirais/uso terapêutico , Biomarcadores/sangue , Biópsia , Quimioterapia Combinada , Feminino , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Interferon-alfa/uso terapêutico , Fígado/patologia , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes , Ribavirina/administração & dosagem , Ribavirina/uso terapêutico , Sensibilidade e Especificidade , Resultado do Tratamento
12.
J Viral Hepat ; 15(8): 571-7, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18363671

RESUMO

Ribavirin has a minor and transient effect on hepatitis C virus (HCV) replication and has been suggested to select a novel mutation, F415Y, in the RNA-dependent RNA polymerase of subtype 1a viruses. Twenty-nine patients with chronic hepatitis C (subtyped by INNO LiPA as 1a, 17; 1b, 11; 1a/1b, 1) who were nonresponders to interferon-based therapies were identified retrospectively and screened at Baseline, week 24 of treatment, and 24 weeks post-treatment. Selection of resistance mutations, including at amino acid position 415 of the polymerase, was investigated. Using clonal sequencing and pyrosequencing of the NS5B gene, we screened for the F415Y resistance mutation among patients who received combination therapy with ribavirin and interferon α. Of the 15 subtype 1a patients treated with interferon plus ribavirin, only one had the F415Y change at week 24, and an F/Y mixture was still present 24 weeks after therapy. Four additional patients in this group had the F415Y change 24 weeks post-therapy. The NS5B genes were sequenced in order to identify amino acid changes associated with ribavirin therapy, but no evidence was found that ribavirin selects for particular amino acids in the RNA-dependent RNA polymerase. Ribavirin, a weak inhibitor of HCV replication, does not select for resistance mutations in the sequence of the HCV RNA polymerase.


Assuntos
Farmacorresistência Viral , Hepacivirus/efeitos dos fármacos , Interferons/farmacologia , Mutação , Ribavirina/farmacologia , Seleção Genética , Proteínas não Estruturais Virais/genética , Adulto , Antivirais/farmacologia , Antivirais/uso terapêutico , Feminino , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Humanos , Interferons/uso terapêutico , Masculino , Pessoa de Meia-Idade , RNA Polimerase Dependente de RNA/genética , Ribavirina/uso terapêutico
13.
J Clin Invest ; 100(9): 2376-85, 1997 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-9410918

RESUMO

This study was performed to test the hypothesis that cytotoxic T lymphocyte (CTL) selection of hepatitis C virus (HCV) escape variants plays a role in HCV persistence. The peripheral blood CTL responsiveness of patients with well-established chronic hepatitis C to a panel of 10 prototype HCV peptides (genotype 1a) was compared with the corresponding sequences encoded by the infecting viruses in each patient. Variant viral peptide sequences were threefold more frequent in the presence of a CTL response than in its absence, and CTL responses were detected nearly twice as often in association with variant rather than with prototype viral peptide sequences. Furthermore, over half of the patients were infected with potential CTL escape variants that contained nonimmunogenic and noncross-reactive variant peptides many of which displayed reduced HLA-binding affinity. Surprisingly, follow up analysis over a period of up to 46 mo revealed that, in contrast to the relatively high frequency of escape variants initially observed, the subsequent emergence rate of CTL escape variants was very low. Interestingly, the one escape variant that was detected proved to be a CTL antagonist. Collectively, these observations suggest that CTL selection of epitope variants may have occurred in these patients before their entrance into the study and that it may have played a role in HCV persistence. The low apparent rate of ongoing CTL selection in chronically infected patients, however, suggests that if CTL escape occurs during HCV infection it is probably an early event.


Assuntos
Hepacivirus/imunologia , Antígenos de Hepatite/imunologia , Hepatite C/imunologia , Linfócitos T Citotóxicos/imunologia , Adulto , Sequência de Aminoácidos , Doença Crônica , Reações Cruzadas , Citotoxicidade Imunológica , Feminino , Antígeno HLA-A2/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/imunologia , Ligação Proteica , Relação Estrutura-Atividade
14.
J Clin Invest ; 98(6): 1432-40, 1996 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-8823309

RESUMO

Hepatitis C virus (HCV)-specific cytotoxic T lymphocytes (CTL) are present in the peripheral blood and liver of chronically infected patients. The current study was performed to study the relationship between the strength of the CTL response, liver disease severity, and viral load. The results may be summarized as follows: first, using CTL precursor frequency (CTLpf) analysis to quantitate the peripheral blood CTL response, chronically infected patients were less strongly sensitized to a panel of well-defined HCV epitopes than they were to an epitope within the influenza matrix protein. Second, HCV-specific CTLpf did not correlate with disease activity or viral load in the majority of patients on a cross-sectional basis, although it did increase in three patients concomitant with sharp increases in liver disease. Finally, interferon therapy did not enhance the CTLpf against the HCV epitopes studied in these patients, indicating that its antiviral effect is independent of the CTL response. Since the HCV-specific CTLpf in the blood is actually quite low, the CTL may contribute to ongoing liver disease in these patients while being quantitatively inadequate to destroy all of the infected hepatocytes, thereby facilitating HCV persistence and contributing to chronic liver disease.


Assuntos
Hepatite C/sangue , Hepatite C/imunologia , Linfócitos T Citotóxicos/imunologia , Adulto , Estudos Transversais , Epitopos/análise , Feminino , Hepatite C/tratamento farmacológico , Humanos , Interferons/uso terapêutico , Fígado/virologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Orthomyxoviridae/imunologia , RNA Viral/análise , Proteínas Virais/síntese química , Proteínas Virais/imunologia
15.
J Clin Invest ; 95(2): 521-30, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7860734

RESUMO

The HLA class I-restricted cytotoxic T lymphocyte (CTL) response is a major defense mechanism in viral infections. It has been suggested that the CTL response may contribute to viral clearance and liver cell injury during hepatitis C virus (HCV) infection. To test this hypothesis requires an understanding of the characteristics of HCV-specific cytotoxic effector cells and identification of the target antigens to which they respond. To begin this process we stimulated peripheral blood mononuclear cells (PBMC) from a group of HLA-A2 positive patients with chronic hepatitis C with a panel of 130 HCV-derived peptides containing the HLA-A2 binding motif. Effector cells were tested for their capacity to lyse HLA-A2-matched target cells that were either sensitized with peptide or infected with a vaccinia virus construct containing HCV sequences. Using this approach we have identified nine immunogenic peptides in HCV, three of which are derived from the putative core protein, three from the nonstructural (NS) 3 domain, two from NS4 and one from NS5. Selected responses were shown to be HLA-A2 restricted, mediated by CD8+ T cells and to recognize endogenously synthesized viral antigen. Unexpectedly, peptide-specific CTL responses could also be induced in sero-negative individuals, suggesting in vitro activation of naive CTL precursors. The precursor frequency of peptide-specific CTL was 10 to 100-fold higher in infected patients compared to uninfected controls, and the responses were greatly diminished by removal of CD45 RO+ (memory) T cells. Further quantitative studies are clearly required to establish whether a correlation exists between the HCV-specific CTL response and the clinical course of this disease. Definition of the molecular targets of the human CTL response to HCV creates this opportunity, and may also contribute to the development of a T cell-based HCV vaccine.


Assuntos
Antígenos Virais/imunologia , Antígeno HLA-A2/imunologia , Hepacivirus/imunologia , Linfócitos T Citotóxicos/imunologia , Sequência de Aminoácidos , Antígenos Virais/biossíntese , Sítios de Ligação , Linfócitos T CD8-Positivos/imunologia , Células Clonais , Citotoxicidade Imunológica , Humanos , Antígenos Comuns de Leucócito/imunologia , Depleção Linfocítica , Dados de Sequência Molecular , Fragmentos de Peptídeos/imunologia
16.
Aliment Pharmacol Ther ; 26 Suppl 1: 29-39, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17958517

RESUMO

BACKGROUND: Patients with chronic liver disease and hepatitis C virus (HCV) frequently experience thrombocytopenia that complicates the management of their disease. Traditional therapy for thrombocytopenia consists of platelet transfusion, which can be associated with significant safety and economic issues. Consequently, efforts have been directed toward developing novel approaches for the treatment of thrombocytopenia. AIM: To summarize the available data on the limitations of traditional therapies and the effects of novel therapies currently in clinical development for the treatment of thrombocytopenia. RESULTS: Recent research has begun to reveal the complex mechanisms that regulate thrombopoiesis. Cytokines and growth factors, such as interleukin-11 and thrombopoietin (TPO), play a key role in the production of platelets. A number of recent clinical studies have provided evidence that pharmacologic agents that target megakaryocyte precursors and stimulate thrombopoiesis can effectively reverse thrombocytopenia. Here, we review the regulation of thrombopoiesis, the role of TPO, and a number of novel compounds that stimulate platelet production by acting through the TPO receptor. Agents that stimulate TPO include the orally available nonpeptidic agonists eltrombopag and AKR-501, peptidic agonists AMG-531 and Peg-TPOmp, and small engineered antibodies. CONCLUSION: Results from clinical trials with these agents in healthy subjects confirm that activation of thrombopoiesis via the TPO pathway is an effective method of stimulating platelet production. This approach may provide safer, more effective treatment for thrombocytopenia in patients with chronic liver disease. Several of these agents are currently being tested in large scale trials.


Assuntos
Antivirais/uso terapêutico , Hematínicos/uso terapêutico , Hepatite C/complicações , Hepatopatias/complicações , Trombocitopenia/tratamento farmacológico , Doença Crônica , Citocinas/uso terapêutico , Humanos , Administração dos Cuidados ao Paciente , Receptores de Trombopoetina/agonistas , Receptores de Trombopoetina/uso terapêutico , Trombocitopenia/etiologia
17.
Aliment Pharmacol Ther ; 43(3): 356-63, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26560052

RESUMO

BACKGROUND: Assessment of fibrosis progression in chronic liver disease relies upon non-invasive tools and changes in semi-quantitative histopathology scores that may not be reliable. AIM: To assess the diagnostic performance of the FibroSURE (FS) index and collagen/alpha smooth muscle actin (α-SMA) morphometry in relation to longitudinal changes in fibrosis on paired biopsies. METHODS: The study cohort included 201 chronic hepatitis C (CHC) nonresponders enrolled in a prior phase II anti-fibrotic study. Serum FS and paired biopsies, with both collagen and α-SMA morphometry, were evaluated at baseline and week 52. RESULTS: Study patients were mostly male (67%) and Caucasian (77%), with Ishak stages 2 (n = 79), 3 (n = 88) and 4 (n = 30), excluded (n = 4 stage 1 or 5). Mean biopsy length was 22.9 mm. For baseline Ishak 2/3 vs. 4, there were no significant differences in AUROCs for collagen (0.71), SMA (0.66) or FS (0.70). At week 52, 62% of patients had no change in Ishak stage, but collagen/α-SMA increased by 34-51% (P < 0.0001), and FS decreased by 5% (P = 0.008). Among the 33% of patients with +/-1 Ishak stage change, FS changes were not significant, but α-SMA increased 29-72%, and collagen increased by 12-38% (P = 0.01 for +1 only). CONCLUSIONS: Longitudinal changes in collagen and α-SMA morphometry are apparent prior to change in histological stage or FibroSURE in CHC nonresponders with intermediate fibrosis. This likely reflects quantitative morphological differences that are not detected by routine histological staging or serum markers such as FibroSURE.


Assuntos
Actinas/biossíntese , Colágeno/metabolismo , Hepatite C Crônica/complicações , Cirrose Hepática/etiologia , Cirrose Hepática/fisiopatologia , Fatores Etários , Biomarcadores , Biópsia , Estudos de Coortes , Progressão da Doença , Feminino , Hepatite C Crônica/sangue , Humanos , Cirrose Hepática/sangue , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Músculo Liso/patologia , Fatores Sexuais
18.
Aliment Pharmacol Ther ; 43(12): 1319-29, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27098374

RESUMO

BACKGROUND: For liver transplant recipients with hepatitis C virus (HCV) and human immunodeficiency virus (HIV) co-infection, recurrence after LT is associated with a higher risk of graft loss than for HCV mono-infected patients. Prior HCV treatment options were limited by side effects and drug-drug interactions. AIM: To evaluate treatment outcomes with sofosbuvir (SOF)-based therapy among HIV/HCV coinfected liver transplant recipients. METHODS: Access to SOF and ribavirin (RBV) prior to regulatory approval was attained via an international compassionate access program for transplant recipients with a life expectancy of 1 year or less in the absence of HCV treatment. This report focuses on the short and longer term outcomes in HCV-HIV co-infected liver transplant recipients. RESULTS: Twenty patients were treated, nine with early severe recurrence and 11 with cirrhosis. Eleven patients received SOF and RBV, one SOF, RBV and Peg-interferon, three SOF, RBV and simeprevir and five SOF, RBV and daclatasvir. Of the 18 patients who completed treatment, 16 (89%) achieved sustained virological response 12 weeks after the end of treatment (SVR12). Liver function tests (including bilirubin and albumin) improved significantly over time. Nineteen serious adverse events occurred in eight (40%) patients, none of them related to SOF. Two patients died during treatment and another, 1 year after the end of therapy, due to progressive end-stage liver disease. Importantly, HIV suppression was not compromised. No significant drug-drug interactions were reported. CONCLUSIONS: Sofosbuvir-based regimens are safe, well-tolerated and provide high rates of SVR in HCV-HIV co-infected patients with severe recurrence after-liver transplant.


Assuntos
Antivirais/uso terapêutico , Coinfecção/tratamento farmacológico , Infecções por HIV/tratamento farmacológico , Hepatite C Crônica/tratamento farmacológico , Sofosbuvir/uso terapêutico , Adulto , Carbamatos , Quimioterapia Combinada , Doença Hepática Terminal/tratamento farmacológico , Feminino , Humanos , Imidazóis/uso terapêutico , Interferons/uso terapêutico , Cirrose Hepática/tratamento farmacológico , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Pirrolidinas , Recidiva , Ribavirina/uso terapêutico , Simeprevir/uso terapêutico , Transplantados , Resultado do Tratamento , Valina/análogos & derivados
19.
Aliment Pharmacol Ther ; 44(2): 157-69, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27218676

RESUMO

BACKGROUND: Matrix metalloproteinase-9 is a proteolytic enzyme whose expression is increased in ulcerative colitis. AIM: To evaluate the safety and efficacy of GS-5745, a fully humanised anti-matrix metalloproteinase-9 monoclonal antibody, in moderately-to-severely active ulcerative colitis. METHODS: We randomised 74 patients with ulcerative colitis to treatment with single or multiple ascending intravenous or subcutaneous doses of GS-5745 or placebo. Multiple-dose cohorts received either IV infusions (0.3, 1.0, 2.5 or 5.0 mg/kg GS-5745 or placebo) every 2 weeks (three total IV infusions) or five weekly SC injections (150 mg GS-5745 or placebo). The primary outcomes were the safety, tolerability and pharmacokinetics of escalating single and multiple doses of GS-5745. Exploratory analyses in the multiple-dose cohorts included clinical response (≥3 points or 30% decrease from baseline in Mayo Clinic score and ≥1 point decrease in the rectal bleeding subscore or a rectal bleeding subscore ≤1) and clinical remission (a complete Mayo Clinic score ≤2 with no subscore >1) at Day 36. Biological effects associated with a clinical response to GS-5745 were explored using histological and molecular approaches. RESULTS: Twenty-three of the 42 patients (55%) receiving multiple doses of GS-5745 had adverse events, compared with 5/8 patients (63%) receiving placebo. GS-5745 showed target-mediated drug disposition, approximately dose-proportional increases in maximum plasma concentration and more than dose-proportional increases in the area under the plasma drug concentration-time curve. Clinical response occurred in 18/42 patients (43%) receiving GS-5745 compared with 1/8 patients (13%) receiving placebo. Clinical remission occurred in 6/42 patients (14%) receiving GS-5745 and 0/8 (0%) receiving placebo. Patients with a clinical response to GS-5745 had reductions in matrix metalloproteinase-9 tissue levels (mean 48.9% decrease from baseline compared with a mean 18.5% increase in nonresponders, P = 0.008) significant improvements in histopathology scores (confirmed with three separate histological disease activity indices), as well as changes in colonic gene expression that were consistent with reduced inflammation. CONCLUSION: This phase 1 trial provides preliminary evidence for the safety and therapeutic potential of GS-5745 in the treatment of ulcerative colitis.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Colite Ulcerativa/tratamento farmacológico , Metaloproteinase 9 da Matriz/imunologia , Adulto , Anticorpos Monoclonais Humanizados , Relação Dose-Resposta a Droga , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
20.
J Interferon Cytokine Res ; 18(2): 75-80, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9506457

RESUMO

Although serum alanine aminotransferase (ALT) and hepatitis C virus (HCV) RNA concentrations are primary markers used to assess the clinical benefit of interferon (IFN) therapy in patients with chronic HCV infection, discrepancies between these two variables exist. In this study, 103 patients with chronic hepatitis C were treated with 3 MIU IFN-alpha2b three times weekly for 24 weeks, followed by 24 weeks of observation. ALT and virologic responses were compared in patients with high pretreatment HCV RNA titers (defined as pretreatment HCV RNA concentrations at or above the 75th percentile of the distribution or >5,000,000 copies/ml) and low pretreatment HCV RNA titers (defined as pretreatment concentrations below the 75th percentile or < or =5,000,000 copies/ml). Analysis of the virologic response for the high-titer and low-titer groups demonstrated a significantly greater HCV RNA sustained response in the low-titer group (21%) compared with the high-titer group (7%) (p < 0.05). In contrast, the ALT sustained response was not significantly different between the low-titer group (21%) and the high-titer group (18%). Analysis of the correspondence between biochemical and virologic responses showed that only 38% of patients with high pretreatment HCV RNA titers had both a sustained ALT response and a sustained loss of HCV RNA compared with 75% of patients with low pretreatment HCV RNA titers. The level of agreement between the ALT and HCV RNA responses was greater for the low-titer group compared with the high-titer group (kappa = .6848 and kappa = .4966, respectively). Our results indicate that chronic HCV patients with high pretreatment HCV RNA titers showed greater discordance between sustained ALT and HCV RNA responses compared with patients with low pretreatment HCV RNA titers and that measurement of HCV RNA should be included in the assessment of response to IFN therapy in chronic hepatitis C patients.


Assuntos
Alanina Transaminase/sangue , Antivirais/uso terapêutico , Hepacivirus/isolamento & purificação , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Adulto , Feminino , Hepatite C Crônica/sangue , Hepatite C Crônica/enzimologia , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , RNA Viral/isolamento & purificação , Proteínas Recombinantes , Titulometria , Resultado do Tratamento
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