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1.
Am J Gastroenterol ; 116(12): 2399-2409, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34382947

RESUMO

INTRODUCTION: AXA1125 and AXA1957 are novel, orally administered endogenous metabolic modulator compositions, specifically designed to simultaneously support multiple metabolic and fibroinflammatory pathways associated with nonalcoholic fatty liver disease (NAFLD). This study assessed safety, tolerability, and biologic activity of AXA1125 and AXA1957 in NAFLD. METHODS: In this multicenter, 16-week, placebo-controlled, single-blind, randomized clinical study in subjects with NAFLD stratified by type 2 diabetes, AXA1125 24 g, AXA1957 13.5 g or 20.3 g, or placebo was administered twice daily. Key metabolism (MRI-proton density fat fraction [MRI-PDFF] and homeostasis model assessment of insulin resistance [HOMA-IR]) and fibroinflammation markers (alanine aminotransferase [ALT], corrected T1 [cT1], keratin-18 [K-18] M65, and N-terminal type III collagen propeptide [Pro-C3]) were evaluated. Safety outcomes included adverse events and standard laboratory assessments. RESULTS: Baseline characteristics of the 102 enrolled subjects, including 40 with type 2 diabetes, were consistent with presumed nonalcoholic steatohepatitis. AXA1125 showed consistently greater biologic activity than AXA1957 or placebo. Week 16 changes from baseline with AXA1125 vs placebo: MRI-PDFF -22.9% vs -5.7%, HOMA-IR -4.4 vs +0.7, ALT -21.9% vs -7.2%, K-18 M65 -13.6% vs +20.1%, cT1 -69.6 vs +18.3 ms (P < 0.05), and Pro-C3 -13.6% vs -3.6%. Week 16 changes from baseline with AXA1957 20.3 g: MRI-PDFF -8.1%, HOMA-IR +8.4, ALT -20.7%, K-18 M65 6.6%, cT1 -34.7 ms, and Pro-C3 -15.6%. A greater proportion of subjects treated with AXA1125 achieved clinically relevant thresholds: ≥30% MRI-PDFF, ≥17-IU/L ALT, and ≥80-ms cT1 reductions at week 16. Study products were safe and well tolerated with stable lipid and weight profiles. DISCUSSION: Both compositions showed multitargeted activity on relevant NAFLD pathways. AXA1125 demonstrated the greatest activity over 16 weeks, warranting continued clinical investigation in nonalcoholic steatohepatitis subjects.


Assuntos
Acetilcisteína/administração & dosagem , Arginina/administração & dosagem , Diabetes Mellitus Tipo 2/complicações , Tolerância a Medicamentos , Glutamina/administração & dosagem , Isoleucina/administração & dosagem , Leucina/administração & dosagem , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Valina/administração & dosagem , Administração Oral , Diabetes Mellitus Tipo 2/diagnóstico , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Feminino , Humanos , Fígado/efeitos dos fármacos , Fígado/patologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Método Simples-Cego , Resultado do Tratamento
2.
Hepatology ; 56(6): 2094-105, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22806830

RESUMO

UNLABELLED: Hepatitis C virus (HCV)-specific immune effector responses can cause liver damage in chronic infection. Hepatic stellate cells (HSC) are the main effectors of liver fibrosis. TGFß, produced by HCV-specific CD8(+) T cells, is a key regulatory cytokine modulating HCV-specific effector T cells. Here we studied TGFß as well as other factors produced by HCV-specific intrahepatic lymphocytes (IHL) and peripheral blood cells in hepatic inflammation and fibrogenesis. This was a cross-sectional study of two well-defined groups of HCV-infected subjects with slow (≤ 0.1 Metavir units/year, n = 13) or rapid (n = 6) liver fibrosis progression. HCV-specific T-cell responses were studied using interferon-gamma (IFNγ)-ELISpot ±monoclonal antibodies (mAbs) blocking regulatory cytokines, along with multiplex, enzyme-linked immunosorbent assay (ELISA) and multiparameter fluorescence-activated cell sorting (FACS). The effects of IHL stimulated with HCV-core peptides on HSC expression of profibrotic and fibrolytic genes were determined. Blocking regulatory cytokines significantly raised detection of HCV-specific effector (IFNγ) responses only in slow fibrosis progressors, both in the periphery (P = 0.003) and liver (P = 0.01). Regulatory cytokine blockade revealed HCV-specific IFNγ responses strongly correlated with HCV-specific TGFß, measured before blockade (R = 0.84, P = 0.0003), with only a trend to correlation with HCV-specific IL-10. HCV-specific TGFß was produced by CD8 and CD4 T cells. HCV-specific TGFß, not interleukin (IL)-10, inversely correlated with liver inflammation (R = -0.63, P = 0.008) and, unexpectedly, fibrosis (R = -0.46, P = 0.05). In addition, supernatants from HCV-stimulated IHL of slow progressors specifically increased fibrolytic gene expression in HSC and treatment with anti-TGFß mAb abrogated such expression. CONCLUSION: Although TGFß is considered a major profibrogenic cytokine, local production of TGFß by HCV-specific T cells appeared to have a protective role in HCV-infected liver, together with other T-cell-derived factors, ameliorating HCV liver disease progression.


Assuntos
Linfócitos T CD8-Positivos/metabolismo , Hepacivirus/imunologia , Células Estreladas do Fígado/metabolismo , Hepatite C Crônica/metabolismo , Cirrose Hepática/imunologia , Linfócitos T Reguladores/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Adulto , Idoso , Linfócitos T CD8-Positivos/imunologia , Colágeno Tipo I/genética , Cadeia alfa 1 do Colágeno Tipo I , Estudos Transversais , Progressão da Doença , Feminino , Expressão Gênica , Hepatite C Crônica/imunologia , Hepatite C Crônica/patologia , Humanos , Interferon gama/metabolismo , Interleucina-10/metabolismo , Fígado/imunologia , Fígado/metabolismo , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Masculino , Metaloproteinase 1 da Matriz/genética , Pessoa de Meia-Idade , Linfócitos T Reguladores/imunologia , Proteínas do Core Viral/imunologia
3.
J Acquir Immune Defic Syndr ; 55(5): 597-605, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-20921898

RESUMO

BACKGROUND: Hepatitis C virus (HCV)/HIV coinfection treatment is suboptimal with low sustained viral response rates to standard therapies. A multicenter randomized clinical trial designed to assess the efficacy/safety of pegylated interferon maintenance therapy was performed by the National Institutes of Health-funded AIDS Clinical Trials Group network. METHODS: HCV treatment-naive and nonresponding interferon-experienced subjects with confirmed HCV and HIV, CD4 >200 cells per cubic millimeter, and at least stage 1 fibrosis were enrolled and treated for 12 weeks with pegylated interferon alfa 2a 180 mcg per week (PEG) + weight-based ribavirin to determine response status. Nonresponder subjects (failure to clear HCV RNA or achieve 2-log drop) underwent liver biopsy and were randomized to receive full dose PEG or observation only for 72 weeks. Paired biopsies were evaluated by a central pathologist. RESULTS: Three hundred thirty subjects were enrolled; median age was 48 years; 43% white, 37% black, non-Hispanic; 83% male; CD4+ 498 cells per cubic millimeter; 32% were interferon experienced; 74% had entry HIV RNA <50 copies per milliliter. early virologic responder was observed in 55.9% and 42.5% achieved complete Early Viral Response (cEVR). A planned interim analysis of occurred when 84 subjects were randomized. With data on 40 paired biopsies available, a safety monitoring board stopped the trial due to lack of fibrosis progression (median = 0 Metavir units/year) in the observation arm. CONCLUSIONS: Lack of fibrotic progression in the control arm was unexpected and may represent a short-term PEG/ribavirin therapy effect, high levels of HIV viral suppression, and use of antiretroviral regimens that may be less toxic than prior generations of therapy.


Assuntos
Antivirais/uso terapêutico , Infecções por HIV/tratamento farmacológico , Hepatite C/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Adulto , Antivirais/administração & dosagem , Antivirais/farmacologia , Contagem de Linfócito CD4 , Quimioterapia Combinada , Feminino , Infecções por HIV/complicações , HIV-1/efeitos dos fármacos , Hepacivirus/efeitos dos fármacos , Hepatite C/complicações , Humanos , Interferon-alfa/administração & dosagem , Interferon-alfa/farmacologia , Fígado/fisiopatologia , Fígado/virologia , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/patologia , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/farmacologia , RNA Viral , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Ribavirina/administração & dosagem , Ribavirina/farmacologia , Ribavirina/uso terapêutico , Resultado do Tratamento
4.
J Gen Virol ; 86(Pt 12): 3291-3301, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16298974

RESUMO

Hepatitis C virus (HCV) infection is associated with inflammation of liver endothelium, which contributes to the pathogenesis of chronic hepatitis. The mechanism of this endothelitis is not understood, since the virus does not appear to infect endothelial cells productively. Here, an 'innocent bystander' mechanism related to HCV proteins was hypothesized and it was investigated whether the binding of HCV particles to human endothelium induced functional changes in the cells. Exposure of human umbilical vein endothelial cells (HUVECs) to HCV-like particles (HCV-LPs) resulted in increased interleukin 8 (IL8) production and induction of apoptosis. The IL8 supernatants collected after stimulation of HUVECs with HCV-LPs, BV-GUS (control baculovirus containing beta-glucuronidase) and appropriate controls were used to assay the transendothelial migration of neutrophils. This assay confirmed that HCV-LP-induced IL8 was functionally active. Using specific NF-kappaB inhibitors, it was also shown that HCV-LP-induced NF-kappaB activity mediated IL8 production in HUVECs. Apoptosis appeared to be mediated by the Fas/Fas-L pathway, as neutralizing antibodies for Fas and Fas-L significantly protected HUVECs against HCV-LP-induced apoptosis. Treatment of HUVECs with HCV-LPs also enhanced cellular Fas-L expression and augmented caspase-3 activation. This was confirmed by using a specific caspase-3 inhibitor, Z-Asp-Glu-Val-Asp-fluoromethyl ketone. As shown by blocking of specific chemokine receptors for IL8 on HUVECs, the induction of IL8 did not appear to contribute to HCV-LP-induced apoptosis. These results suggest that HCV proteins can trigger the release of inflammatory chemokines such as IL8 and cause endothelial apoptosis, thereby facilitating endothelitis.


Assuntos
Apoptose , Células Endoteliais/citologia , Células Endoteliais/virologia , Endotélio Vascular/citologia , Hepacivirus/patogenicidade , Interleucina-8/biossíntese , Proteínas Estruturais Virais/fisiologia , Caspase 3 , Caspases/análise , Inibição de Migração Celular , Células Cultivadas , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Endotélio Vascular/virologia , Proteína Ligante Fas , Humanos , Glicoproteínas de Membrana/análise , Glicoproteínas de Membrana/antagonistas & inibidores , NF-kappa B/análise , Inibidores do Fator de Necrose Tumoral , Fatores de Necrose Tumoral/análise , Virossomos , Receptor fas
5.
N Engl J Med ; 351(5): 451-9, 2004 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-15282352

RESUMO

BACKGROUND: Chronic hepatitis C virus (HCV) infection is a cause of major complications in persons who are also infected with the human immunodeficiency virus (HIV). However, the treatment of HCV infection in such persons has been associated with a high rate of intolerance and a low rate of response. We conducted a multicenter, randomized trial comparing peginterferon plus ribavirin with interferon plus ribavirin for the treatment of chronic hepatitis C in persons coinfected with HIV. METHODS: A total of 66 subjects were randomly assigned to receive 180 microg of peginterferon alfa-2a weekly for 48 weeks, and 67 subjects were assigned to receive 6 million IU of interferon alfa-2a three times weekly for 12 weeks followed by 3 million IU three times weekly for 36 weeks. Both groups received ribavirin according to a dose-escalation schedule. At week 24, subjects who did not have a virologic response (those who had an HCV RNA level greater than or equal to 60 IU per milliliter) underwent liver biopsy, and medications were continued in subjects with either a virologic response or histologic improvement. RESULTS: Treatment with peginterferon and ribavirin was associated with a significantly higher rate of sustained virologic response (an HCV RNA level of less than 60 IU per milliliter 24 weeks after completion of therapy) than was treatment with interferon and ribavirin (27 percent vs. 12 percent, P=0.03). In the group given peginterferon and ribavirin, only 14 percent of subjects with HCV genotype 1 infection had a sustained virologic response (7 of 51), as compared with 73 percent of subjects with an HCV genotype other than 1 (11 of 15, P<0.001). Histologic responses were observed in 35 percent of subjects with no virologic response who underwent liver biopsy. CONCLUSIONS: In persons infected with HIV, the combination of peginterferon and ribavirin is superior to the combination of interferon and ribavirin in the treatment of chronic hepatitis C. These regimens may provide clinical benefit even in the absence of virologic clearance. The marked discrepancy in the rates of sustained virologic response between HCV genotypes indicates that strategies are needed to improve the outcome in persons infected with HCV genotype 1.


Assuntos
Antivirais/uso terapêutico , Infecções por HIV/complicações , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis , Ribavirina/uso terapêutico , Adulto , Análise de Variância , Antivirais/efeitos adversos , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/efeitos dos fármacos , Hepacivirus/genética , Anticorpos Anti-Hepatite C/sangue , Hepatite C Crônica/complicações , Humanos , Interferon alfa-2 , Interferon-alfa/efeitos adversos , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Proteínas Recombinantes , Ribavirina/efeitos adversos
6.
J Infect Dis ; 189(7): 1140-50, 2004 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-15031780

RESUMO

The kinetics of intrahepatic hepatitis C virus (HCV)-specific CD4(+) T cell responses and their role in progression of fibrosis have not previously been characterized. Subjects with HCV/Schistosoma mansoni coinfection have a more rapid progression of HCV liver fibrosis than do those with HCV infection alone. The present prospective longitudinal study compared the liver histology, HCV-specific intrahepatic and peripheral CD4(+) T cell proliferative responses, and cytokines (enzyme-linked immunospot) in 48 subjects with unresolved acute HCV infection with or without S. mansoni coinfection, at 6-10 months after acute infection and at the end of follow-up (96+/-8.7 months), and the findings were correlated to the rate of progression of fibrosis per year. Coinfected subjects had significant worsening of fibrosis, compared with subjects with HCV infection alone. At baseline, subjects with HCV infection alone had stronger multispecific intrahepatic HCV-specific CD4(+) T helper 1 responses than did coinfected subjects, who had either no responses or weak, narrowly focused responses, and, over time, these T cell responses were maintained only in the liver. The rate of progression of fibrosis and virus load inversely correlated with intrahepatic HCV-specific CD4(+) T cell response. The present prospective analysis indicates that enhancement of progression of liver fibrosis is associated with failure to develop early, multispecific, HCV-specific CD4(+) Th1 responses, suggesting that novel therapeutic approaches inducing strong cellular immune responses might limit subsequent liver damage in individuals with chronic hepatitis C.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Hepacivirus/imunologia , Hepatite C Crônica/parasitologia , Cirrose Hepática/parasitologia , Cirrose Hepática/virologia , Schistosoma mansoni/imunologia , Esquistossomose mansoni/virologia , Adulto , Animais , Biópsia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/virologia , Divisão Celular/imunologia , Estudos de Coortes , Progressão da Doença , Feminino , Hepatite C Crônica/imunologia , Hepatite C Crônica/patologia , Humanos , Cirrose Hepática/patologia , Estudos Longitudinais , Masculino , Estudos Prospectivos , Esquistossomose mansoni/imunologia , Esquistossomose mansoni/patologia , Estatísticas não Paramétricas
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