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1.
Vox Sang ; 117(7): 913-919, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35405038

RESUMO

The buffy coat method as a source for platelet concentrates was developed in the 1970s and is still used in many blood centres around the world. Development of the method sparked various technological advances in blood collection, processing and storage. At the time, the need for platelet concentrates sharply increased because of better treatment regimens for (onco)haematological diseases, which forced blood centres to standardize and automate their production processes as much as the technology would allow. In this review, a historical overview of the Dutch experiences is provided in the context of the international developments.


Assuntos
Plaquetas , Preservação de Sangue , Buffy Coat , Humanos
2.
Clin Infect Dis ; 69(11): 1969-1979, 2019 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-30715261

RESUMO

BACKGROUND: (Pegylated) Interferon ([Peg]IFN) therapy leads to response in a minority of chronic hepatitis B (CHB) patients. Host genetic determinants of response are therefore in demand. METHODS: In this genome-wide association study (GWAS), CHB patients, treated with (Peg)IFN for at least 12 weeks ± nucleos(t)ide analogues within randomized trials or as standard of care, were recruited at 21 centers from Europe, Asia, and North America. Response at 24 weeks after (Peg)IFN treatment was defined as combined hepatitis B e antigen (HBeAg) loss with hepatitis B virus (HBV) DNA <2000 IU/mL, or an HBV DNA <2000 IU/mL for HBeAg-negative patients. RESULTS: Of 1144 patients, 1058 (92%) patients were included in the GWAS analysis. In total, 282 (31%) patients achieved the response and 4% hepatitis B surface antigen (HBsAg) loss. GWAS analysis stratified by HBeAg status, adjusted for age, sex, and the 4 ancestry components identified PRELID2 rs371991 (B= -0.74, standard error [SE] = 0.16, P = 3.44 ×10-6) for HBeAg-positive patients. Importantly, PRELID2 was cross-validated for long-term response in HBeAg-negative patients. G3BP2 rs3821977 (B = 1.13, SE = 0.24, P = 2.46 × 10-6) was associated with response in HBeAg-negative patients. G3BP2 has a role in the interferon pathway and was further examined in peripheral blood mononuclear cells of healthy controls stimulated with IFNα and TLR8. After stimulation, less production of IP-10 and interleukin (IL)-10 proteins and more production of IL-8 were observed with the G3BP2 G-allele. CONCLUSIONS: Although no genome-wide significant hits were found, the current GWAS identified genetic variants associated with (Peg)IFN response in CHB. The current findings could pave the way for gene polymorphism-guided clinical counseling, both in the setting of (Peg)IFN and the natural history, and possibly for new immune-modulating therapies. CLINICAL TRIALS REGISTATION: NCT01401400.


Assuntos
Estudo de Associação Genômica Ampla/métodos , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/metabolismo , Interferons/metabolismo , Adulto , Antivirais/uso terapêutico , Feminino , Técnicas de Genotipagem , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos
3.
J Viral Hepat ; 26(1): 109-117, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30187612

RESUMO

Addition of peginterferon alpha (PEG-IFN add-on) to entecavir (ETV) treatment after a short lead-in phase results in more response than ETV monotherapy in HBeAg-positive chronic hepatitis B infection (CHB). This study is the first to assess long-term efficacy of this treatment strategy. Patients who received ETV ± 24 weeks of PEG-IFN add-on in a global trial (ARES study) and completed follow-up were eligible to participate in this observational LTFU study if they had at least one combined HBeAg and HBV DNA measurement beyond week 96 of the ARES study. The primary endpoint was combined response (HBeAg loss and HBV DNA <200 IU/mL) at LTFU. In total, 48 patients treated with PEG-IFN add-on and 48 patients treated with ETV monotherapy were included. The median follow-up duration was 226 (IQR 51) weeks, and 86/96 (90%) patients were initial non-responders. At LTFU, combined response was present in 13 (27%) vs 11 (23%) patients (P = 0.81), and 1 log10  HBsAg decline in 59% vs 28% (P = 0.02) for PEG-IFN add-on and ETV monotherapy, respectively. In 41 initial non-responders who continued ETV therapy, combined response at LTFU was present in 9 patients (PEG-IFN add-on: 5/22 [23%]; ETV monotherapy: 4/19 [21%]). Beyond week 96 of follow-up, rates of serological response became comparable between PEG-IFN add-on and ETV monotherapy. Although in this LTFU study initial non-responders were overrepresented in the add-on arm, PEG-IFN add-on possibly leads rather to accelerated HBeAg loss than to increased long-term HBeAg loss rates.


Assuntos
Antivirais/administração & dosagem , Guanina/análogos & derivados , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/administração & dosagem , Adulto , DNA Viral/sangue , Esquema de Medicação , Quimioterapia Combinada , Feminino , Seguimentos , Guanina/administração & dosagem , Humanos , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Tempo , Adulto Jovem
4.
Lancet ; 389(10070): 709-717, 2017 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-28087069

RESUMO

BACKGROUND: miR-122 is an important host factor for hepatitis C virus (HCV) replication. The aim of this study was to assess the safety and tolerability, pharmacokinetics, and antiviral effect of a single dose of RG-101, a hepatocyte targeted N-acetylgalactosamine conjugated oligonucleotide that antagonises miR-122, in patients with chronic HCV infection with various genotypes. METHODS: In this randomised, double-blind, placebo-controlled, multicentre, phase 1B study, patients were randomly assigned to RG-101 or placebo (7:1). We enrolled men and postmenopausal or hysterectomised women (aged 18-65 years) with chronic HCV genotype 1, 3, or 4 infection diagnosed at least 24 weeks before screening who were either treatment naive to or relapsed after interferon-α based therapy. Patients with co-infection (hepatitis B virus or HIV infection), evidence of decompensated liver disease, or a history of hepatocellular carcinoma were excluded. Randomisation was done by an independent, unblinded, statistician using the SAS procedure Proc Plan. The first cohort received one subcutaneous injection of 2 mg/kg RG-101 or placebo; the second cohort received one subcutaneous injection of 4 mg/kg or placebo. Patients were followed up for 8 weeks (all patients) and up to 76 weeks (patients with no viral rebound and excluding those who were randomised to the placebo group) after randomisation. The primary objective was safety and tolerability of RG-101. This trial was registered with EudraCT, number 2013-002978-49. FINDINGS: Between June 4, 2014, and Oct 27, 2014, we enrolled 32 patients with chronic HCV genotype 1 (n=16), 3 (n=10), or 4 (n=6) infections. In the first cohort, 14 patients were randomly assigned to receive 2 mg/kg RG-101 and two patients were randomly assigned to receive placebo, and in the second cohort, 14 patients were randomly assigned to receive 4 mg/kg RG-101 and two patients were randomly assigned to receive placebo. Overall, 26 of the 28 patients dosed with RG-101 reported at least one treatment-related adverse event. At week 4, the median viral load reduction from baseline was 4·42 (IQR 3·23-5·00) and 5·07 (4·19-5·35) log10 IU/mL in patients dosed with 2 mg/kg RG-101 or 4 mg/kg RG-101. Three patients had undetectable HCV RNA levels 76 weeks after a single dose of RG-101. Viral rebound at or before week 12 was associated with the appearance of resistance associated substitutions in miR-122 binding regions in the 5' UTR of the HCV genome. INTERPRETATION: This study showed that one administration of 2 mg/kg or 4 mg/kg RG-101, a hepatocyte targeted N-acetylgalactosamine conjugated anti-miR-122 oligonucleotide, was well tolerated and resulted in substantial viral load reduction in all treated patients within 4 weeks, and sustained virological response in three patients for 76 weeks. FUNDING: Regulus Therapeutics, Inc.


Assuntos
Hepatite C Crônica/tratamento farmacológico , MicroRNAs/antagonistas & inibidores , MicroRNAs/uso terapêutico , Acetilgalactosamina , Estudos de Coortes , Método Duplo-Cego , Feminino , Humanos , Injeções Subcutâneas , Masculino , MicroRNAs/farmacocinética , Pessoa de Meia-Idade , Oligonucleotídeos , Carga Viral/efeitos dos fármacos
5.
Hepatology ; 66(1): 57-68, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28295463

RESUMO

MicroRNA-122 is an important host factor for the hepatitis C virus (HCV). Treatment with RG-101, an N-acetylgalactosamine-conjugated anti-microRNA-122 oligonucleotide, resulted in a significant viral load reduction in patients with chronic HCV infection. Here, we analyzed the effects of RG-101 therapy on antiviral immunity. Thirty-two chronic HCV patients infected with HCV genotypes 1, 3, and 4 received a single subcutaneous administration of RG-101 at 2 mg/kg (n = 14) or 4 mg/kg (n = 14) or received a placebo (n = 2/dosing group). Plasma and peripheral blood mononuclear cells were collected at multiple time points, and comprehensive immunological analyses were performed. Following RG-101 administration, HCV RNA declined in all patients (mean decline at week 2, 3.27 log10 IU/mL). At week 8 HCV RNA was undetectable in 15/28 patients. Plasma interferon-γ-induced protein 10 (IP-10) levels declined significantly upon dosing with RG-101. Furthermore, the frequency of natural killer (NK) cells increased, the proportion of NK cells expressing activating receptors normalized, and NK cell interferon-γ production decreased after RG-101 dosing. Functional HCV-specific interferon-γ T-cell responses did not significantly change in patients who had undetectable HCV RNA levels by week 8 post-RG-101 injection. No increase in the magnitude of HCV-specific T-cell responses was observed at later time points, including 3 patients who were HCV RNA-negative 76 weeks postdosing. CONCLUSION: Dosing with RG-101 is associated with a restoration of NK-cell proportions and a decrease of NK cells expressing activation receptors; however, the magnitude and functionality of ex vivo HCV-specific T-cell responses did not increase following RG-101 injection, suggesting that NK cells, but not HCV adaptive immunity, may contribute to HCV viral control following RG-101 therapy. (Hepatology 2017;66:57-68).


Assuntos
Hepatite C Crônica/tratamento farmacológico , Células Matadoras Naturais/efeitos dos fármacos , MicroRNAs/antagonistas & inibidores , Linfócitos T/efeitos dos fármacos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , ELISPOT/métodos , Feminino , Citometria de Fluxo , Seguimentos , Hepatite C Crônica/diagnóstico , Humanos , Injeções Subcutâneas , Células Matadoras Naturais/imunologia , Masculino , MicroRNAs/administração & dosagem , Pessoa de Meia-Idade , Terapia de Alvo Molecular/métodos , Países Baixos , Fenótipo , Linfócitos T/imunologia , Resultado do Tratamento
6.
J Infect Dis ; 215(9): 1421-1429, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28368488

RESUMO

Background: Hepatitis B virus (HBV) modulates microRNA (miRNA) expression to support viral replication. The aim of this study was to identify miRNAs associated with hepatitis B e antigen (HBeAg) status and response to antiviral therapy in patients with chronic hepatitis B (CHB) , and to assess if these miRNAs are actively secreted by hepatoma cells. Methods: Plasma miRNA levels were measured by reverse-transcription quantitative polymerase chain reaction in healthy controls (n = 10) and pretreatment samples of an identification cohort (n = 24) and a confirmation cohort (n = 64) of CHB patients treated with peginterferon/nucleotide analogue combination therapy. Levels of HBV-associated miRNAs were measured in cells, extracellular vesicles, and hepatitis B surface antigen (HBsAg) particles of hepatoma cell lines. Results: HBeAg-positive patients had higher plasma levels of miR-122-5p, miR-125b-5p, miR-192-5p, miR-193b-3p, and miR-194-5p compared to HBeAg-negative patients, and levels of these miRNAs were associated with HBV DNA and HBsAg levels. Pretreatment plasma levels of miR-301a-3p and miR-145-5p were higher in responders (combined response or HBsAg loss) compared to nonresponders. miR-192-5p, miR-193b-3p, and miR-194-5p were present in extracellular vesicles and HBsAg particles derived from hepatoma cells. Conclusions: We identified miRNAs that are associated with HBeAg status, levels of HBV DNA and HBsAg, and treatment response in CHB patients. We demonstrated that several of these miRNAs are present in extracellular vesicles and HBsAg particles secreted by hepatoma cells.


Assuntos
Antígenos E da Hepatite B/sangue , Hepatite B Crônica/sangue , Hepatite B Crônica/tratamento farmacológico , MicroRNAs/sangue , Adulto , Antivirais/uso terapêutico , Carcinoma Hepatocelular , Linhagem Celular Tumoral , Estudos de Coortes , Feminino , Hepatite B Crônica/genética , Hepatite B Crônica/virologia , Humanos , Neoplasias Hepáticas , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Resultado do Tratamento
7.
N Engl J Med ; 370(21): 1993-2001, 2014 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-24795201

RESUMO

BACKGROUND: In clinical trials, treatment with a combination of the nucleotide polymerase inhibitor sofosbuvir and the antiviral drug ribavirin was associated with high response rates among patients with hepatitis C virus (HCV) genotype 2 infection, with lower response rates among patients with HCV genotype 3 infection. METHODS: We conducted a study involving patients with HCV genotype 2 or 3 infection, some of whom had undergone previous treatment with an interferon-based regimen. We randomly assigned 91 patients with HCV genotype 2 infection and 328 with HCV genotype 3 infection, in a 4:1 ratio, to receive sofosbuvir-ribavirin or placebo for 12 weeks. On the basis of emerging data from phase 3 trials indicating that patients with HCV genotype 3 infection had higher response rates when they were treated for 16 weeks, as compared with 12 weeks, the study was unblinded, treatment for all patients with genotype 3 infection was extended to 24 weeks, the placebo group was terminated, and the goals of the study were redefined to be descriptive and not include hypothesis testing. The primary end point was a sustained virologic response at 12 weeks after the end of therapy. RESULTS: Of the 419 patients who were enrolled and treated, 21% had cirrhosis and 58% had received previous interferon-based treatment. The criterion for a sustained virologic response was met in 68 of 73 patients (93%; 95% confidence interval [CI], 85 to 98) with HCV genotype 2 infection who were treated for 12 weeks and in 213 of 250 patients (85%; 95% CI, 80 to 89) with HCV genotype 3 infection who were treated for 24 weeks. Among patients with HCV genotype 3 infection, response rates were 91% and 68% among those without and those with cirrhosis, respectively. The most common adverse events were headache, fatigue, and pruritus. CONCLUSIONS: Therapy with sofosbuvir-ribavirin for 12 weeks in patients with HCV genotype 2 infection and for 24 weeks in patients with HCV genotype 3 infection resulted in high rates of sustained virologic response. (Funded by Gilead Sciences; VALENCE ClinicalTrials.gov number, NCT01682720.).


Assuntos
Antivirais/uso terapêutico , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Ribavirina/uso terapêutico , Uridina Monofosfato/análogos & derivados , Adulto , Idoso , Antivirais/efeitos adversos , Farmacorresistência Viral/genética , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Ribavirina/efeitos adversos , Sofosbuvir , Uridina Monofosfato/efeitos adversos , Uridina Monofosfato/uso terapêutico , Carga Viral
8.
J Infect Dis ; 213(2): 224-32, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26216905

RESUMO

BACKGROUND: Treatment of patients with chronic hepatitis B (CHB) with nucleos(t)ide analogues (NAs) suppresses hepatitis B virus (HBV) DNA production but does not affect the synthesis of the RNA pregenome or HBV messenger RNA. Whether HBV RNA-containing particles continue to be secreted into the bloodstream remains controversial. METHODS: We developed a sensitive polymerase chain reaction (PCR) assay to quantify the HBV RNA load in a supernatant of NA-treated HepG2-2.2.15 cells and in plasma specimens from 20 patients with CHB who were receiving NA therapy and 86 patients treated with pegylated interferon alfa (Peg-IFN) and adefovir. RESULTS: Treatment of HepG2-2.2.15 cells with NAs for 9 days reduced HBV DNA levels (by 1.98 log10 copies/mL), whereas HBV RNA levels increased (by 0.47 log10 copies/mL; P < .05). During long-term NA treatment of patients with CHB, HBV RNA levels remained higher than HBV DNA levels. Peg-IFN-based treatment induced a stronger decrease in the HBV RNA load than NA monotherapy, and this decline was more pronounced in responders than in nonresponders. In HBV e antigen-negative patients, a lower baseline plasma HBV RNA level was independently associated with response to Peg-IFN and adefovir (odds ratio, 0.44; P = .019). Immunoprecipitation with HBV core antigen-specific antibodies after removal of the HBV surface antigen envelope demonstrated the association of plasma HBV RNA with virions. CONCLUSIONS: HBV RNA is present in virions in plasma specimens from patients with CHB. HBV RNA levels vary significantly from those of established viral markers during antiviral treatment, which highlights its potential as an independent marker in the evaluation of patients with CHB.


Assuntos
Adenina/análogos & derivados , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Organofosfonatos/uso terapêutico , Polietilenoglicóis/uso terapêutico , RNA Viral/sangue , Vírion/genética , Adenina/administração & dosagem , Adenina/uso terapêutico , Adulto , Amantadina , Antivirais/administração & dosagem , Antivirais/uso terapêutico , Biomarcadores , DNA Viral/genética , DNA Viral/isolamento & purificação , Quimioterapia Combinada , Feminino , Guanina/análogos & derivados , Guanina/uso terapêutico , Células Hep G2 , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/sangue , Hepatite B Crônica/virologia , Humanos , Interferon-alfa/administração & dosagem , Masculino , Pessoa de Meia-Idade , Organofosfonatos/administração & dosagem , Polietilenoglicóis/administração & dosagem , RNA Viral/genética , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/uso terapêutico , Reprodutibilidade dos Testes , Tenofovir/uso terapêutico , Vírion/efeitos dos fármacos
9.
J Hepatol ; 64(3): 539-46, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26505119

RESUMO

BACKGROUND & AIMS: Chronic hepatitis B virus (HBV) infection is characterized by functional impairment of HBV-specific T cells. Understanding the mechanisms behind T cell dysfunction and restoration is important for the development of optimal treatment strategies. METHODS: In this study we have first analysed the phenotype and function of HBV-specific T cells in patients with low viral load (HBV DNA <20,000IU/ml) and spontaneous control over the virus. Subsequently, we assessed HBV-specific T cells in patients with high viral load (HBV DNA >17,182IU/ml) treated with peginterferon/adefovir combination therapy who had various treatment outcomes. RESULTS: HBV-specific T cells could be detected directly ex vivo in 7/22 patients with low viral load. These showed an early differentiated memory phenotype with reduced ability to produce IL-2 and cytotoxic molecules such as granzyme B and perforin, but with strong proliferative potential. In a cohort of 28 chronic hepatitis B patients with high viral load treated with peginterferon and adefovir, HBV-specific T cells could not be detected directly ex vivo. However, HBV-specific T cells could be selectively expanded in vitro in patients with therapy-induced HBsAg clearance (HBsAg loss n=7), but not in patients without HBsAg clearance (n=21). Further analysis of HBV-specific T cell function with peptide pools showed broad and efficient antiviral responses after therapy. CONCLUSIONS: Our results show that peginterferon based combination therapy can induce HBV-specific T cell restoration. These findings may help to develop novel therapeutic strategies to reconstitute antiviral functions and enhance viral clearance.


Assuntos
Antivirais/administração & dosagem , Hepatite B Crônica/imunologia , Linfócitos T/imunologia , Adulto , Idoso , Citocinas/biossíntese , Citotoxicidade Imunológica , Quimioterapia Combinada , Feminino , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/imunologia , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/virologia , Humanos , Interferons/administração & dosagem , Masculino , Pessoa de Meia-Idade , Carga Viral
10.
N Engl J Med ; 368(18): 1685-94, 2013 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-23534542

RESUMO

BACKGROUND: The stability and propagation of hepatitis C virus (HCV) is dependent on a functional interaction between the HCV genome and liver-expressed microRNA-122 (miR-122). Miravirsen is a locked nucleic acid-modified DNA phosphorothioate antisense oligonucleotide that sequesters mature miR-122 in a highly stable heteroduplex, thereby inhibiting its function. METHODS: In this phase 2a study at seven international sites, we evaluated the safety and efficacy of miravirsen in 36 patients with chronic HCV genotype 1 infection. The patients were randomly assigned to receive five weekly subcutaneous injections of miravirsen at doses of 3 mg, 5 mg, or 7 mg per kilogram of body weight or placebo over a 29-day period. They were followed until 18 weeks after randomization. RESULTS: Miravirsen resulted in a dose-dependent reduction in HCV RNA levels that endured beyond the end of active therapy. In the miravirsen groups, the mean maximum reduction in HCV RNA level (log10 IU per milliliter) from baseline was 1.2 (P=0.01) for patients receiving 3 mg per kilogram, 2.9 (P=0.003) for those receiving 5 mg per kilogram, and 3.0 (P=0.002) for those receiving 7 mg per kilogram, as compared with a reduction of 0.4 in the placebo group. During 14 weeks of follow-up after treatment, HCV RNA was not detected in one patient in the 5-mg group and in four patients in the 7-mg group. We observed no dose-limiting adverse events and no escape mutations in the miR-122 binding sites of the HCV genome. CONCLUSIONS: The use of miravirsen in patients with chronic HCV genotype 1 infection showed prolonged dose-dependent reductions in HCV RNA levels without evidence of viral resistance. (Funded by Santaris Pharma; ClinicalTrials.gov number, NCT01200420.).


Assuntos
Antivirais/uso terapêutico , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , MicroRNAs , Oligonucleotídeos/uso terapêutico , Adulto , Idoso , Antivirais/efeitos adversos , Sítios de Ligação/genética , Relação Dose-Resposta a Droga , Feminino , Genótipo , Hepacivirus/isolamento & purificação , Hepatite C Crônica/genética , Humanos , Injeções Subcutâneas , Masculino , MicroRNAs/química , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Mutação , Oligonucleotídeos/efeitos adversos , RNA Viral/sangue
11.
Hepatology ; 61(5): 1512-22, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25348661

RESUMO

UNLABELLED: Entecavir (ETV) is a potent inhibitor of hepatitis B viral replication, but long-term therapy may be required. We investigated whether adding on pegylated interferon (Peg-IFN) to ETV therapy enhances serological response rates. In this global investigator-initiated, open-label, multicenter, randomized trial, hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) patients with compensated liver disease started on ETV monotherapy (0.5 mg/day) and were randomized in a 1:1 ratio to either Peg-IFN add-on therapy (180 µg/week) from week 24 to 48 (n = 85) or to continue ETV monotherapy (n = 90). Response was defined as HBeAg loss with HBV DNA <200 IU/mL at week 48. Responders discontinued ETV at week 72. All patients were followed until week 96. Response was achieved in 16 of 85 (19%) patients allocated to the add-on arm versus 9 of 90 (10%) in the monotherapy arm (P = 0.095). Adjusted for HBV DNA levels before randomized therapy, Peg-IFN add-on was significantly associated with response (odds ratio: 4.8; 95% confidence interval: 1.6-14.0; P = 0.004). Eleven (13%) of the add-on-treated patients achieved disease remission after ETV cessation versus 2 of 90 (2%) of those treated with monotherapy (P = 0.007), which was 79% (11 of 14) versus 25% (2 of 8) of those who discontinued ETV (P = 0.014). At week 96, 22 (26%) patients assigned add-on versus 12 (13%) assigned monotherapy achieved HBeAg seroconversion (P = 0.036). Peg-IFN add-on led to significantly more decline in hepatitis B surface antigen, HBeAg, and HBV DNA (all P < 0.001). Combination therapy was well tolerated. CONCLUSION: Although the primary endpoint was not reached, 24 weeks of Peg-IFN add-on therapy led to a higher proportion of HBeAg response, compared to ETV monotherapy. Add-on therapy resulted in more viral decline and appeared to prevent relapse after stopping ETV. Hence, Peg-IFN add-on therapy may facilitate the discontinuation of nucleos(t)ide analogs.


Assuntos
Antivirais/administração & dosagem , Guanina/análogos & derivados , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/sangue , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/administração & dosagem , Polietilenoglicóis/administração & dosagem , Adulto , Quimioterapia Combinada , Feminino , Guanina/administração & dosagem , Humanos , Interferon alfa-2 , Masculino , Proteínas Recombinantes/administração & dosagem
12.
J Infect Dis ; 212(7): 1042-51, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25791117

RESUMO

BACKGROUND: The role of natural killer (NK) cells in the process of hepatitis B virus (HBV) surface antigen (HBsAg) clearance and whether their phenotype is related to treatment outcome in patients with chronic hepatitis B are currently unknown. METHODS: Patients with chronic hepatitis B (HBV DNA load, >17 000 IU/mL) were treated with pegylated interferon alfa-2a and adefovir for 48 weeks. NK cell phenotype and function were analyzed in 7 responders (defined as individuals with HBsAg clearance by week 72; 3 HBV e antigen [HBeAg]-positive and 4 HBeAg-negative), 7 matched nonresponders, and 7 healthy controls. Subsequently, 34 baseline samples from HBeAg-positive patients with chronic hepatitis B were analyzed. RESULTS: During treatment, the percentage and absolute number of CD56(bright) NK cells increased significantly, whereas the percentage and absolute number of CD56(dim) NK cells decreased. At baseline, responders had a significantly lower expression of chemokine receptor CX3CR1 on CD56(bright) NK cells and inhibitory receptor NKG2A on CD56(dim) NK cells, compared with nonresponders. In addition, responders had higher CD56(bright) TRAIL expression and interferon γ production at end of treatment. These baseline differences were not found in HBeAg-positive patients who had HBeAg seroconversion without HBsAg clearance. CONCLUSIONS: Combination therapy significantly influences NK cell phenotype and function. Differences between patients with chronic hepatitis B with HBsAg clearance and nonresponders suggest that NK cells play a role in the clearance of HBsAg during interferon-based combination therapy.


Assuntos
Adenina/análogos & derivados , Antivirais/uso terapêutico , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Interferon-alfa/uso terapêutico , Células Matadoras Naturais/imunologia , Organofosfonatos/uso terapêutico , Polietilenoglicóis/uso terapêutico , Adenina/uso terapêutico , Adulto , Idoso , Antígenos de Superfície/imunologia , DNA Viral/imunologia , Quimioterapia Combinada , Feminino , Antígenos de Superfície da Hepatite B/imunologia , Antígenos E da Hepatite B/imunologia , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico , Resultado do Tratamento , Adulto Jovem
13.
J Hepatol ; 62(5): 1033-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25514556

RESUMO

BACKGROUND AND AIMS: HBsAg loss is a desired, but rare, treatment-induced clinical endpoint in chronic hepatitis B (CHB). Few studies have evaluated viral factors contributing to HBsAg loss. METHODS: This study evaluated baseline interpatient sequence diversity across the HBV genome in tenofovir disoproxil fumarate-treated patients who lost HBsAg and compared it to that of control patients with high HBsAg levels throughout therapy. Twenty-one HBeAg+ patients (14 genotype (GT) A and 7 GT D) who achieved HBsAg loss and 27 controls (17 GT A and 10 GT D), were analyzed. Population sequencing was performed on baseline samples and pairwise genetic distances were calculated for 17 overlapping regions across the HBV genome as a measure of interpatient viral diversity. RESULTS: Overall, viral diversity was up to 10-fold higher across GT D patients compared to GT A patients throughout the HBV genome. Within the pol/RT and HBs genes, interpatient viral diversity was significantly lower among HBsAg loss patients for both GT A and D, with the difference driven largely by a reduction in diversity in the small S gene. Conversely, interpatient viral diversity was generally higher in HBsAg loss patients across the HBx gene regulatory elements and precore region. CONCLUSION: In HBsAg loss patients, less interpatient viral diversity was observed within structural-coding regions while specific regions across the HBx and precore genes encoding nonstructural regulatory elements generally displayed higher interpatient viral diversity. These distinct patterns may reflect different responses to adaptive pressure for HBV genomic structural and nonstructural elements.


Assuntos
DNA Viral/genética , Variação Genética/efeitos dos fármacos , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B , Hepatite B Crônica , Tenofovir/farmacologia , Adulto , Antivirais/farmacologia , Transmissão de Doença Infecciosa , Feminino , Antígenos E da Hepatite B/genética , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/imunologia , Hepatite B Crônica/transmissão , Hepatite B Crônica/virologia , Humanos , Masculino
14.
Liver Int ; 35(7): 1824-32, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25533046

RESUMO

BACKGROUND & AIMS: Differences in intrahepatic gene expression patterns may be associated with therapy response in peginterferon-treated chronic hepatitis B (CHB) patients. METHODS: We employed gene expression profiling in baseline liver biopsies of 40 CHB patients (19 HBeAg-positive; 21 HBeAg-negative) treated with peginterferon and adefovir for 48 weeks, and compared expression patterns of combined responders (HBeAg loss, HBV-DNA <2000 IU/ml, alanine aminotransferase normalization after 1 year of treatment-free follow-up) with non-responders. Genes identified by transcriptome analysis in 15 biopsies were confirmed in 25 additional biopsies by RT-qPCR. RESULTS: Transcriptome analysis demonstrated significant differences in expression of 41 genes between responders and non-responders. In responders, pathway analysis showed specific upregulation of genes related to the immune response, including chemotaxis and antigen processing and presentation. Genes upregulated in responders exhibited strongest similarity with a set of genes induced in livers of chimpanzees with acute Hepatitis B infection. Differential expression was confirmed for eight selected genes. A 2-gene subset (HLA-DPB1, SERPIN-E1) was found to predict response most accurately. Incorporation of these genes in a multivariable model with HBeAg status, HBV genotype and baseline HBsAg level correctly classified 90% of all patients, in which HLA-DPB1 and SERPIN-E1 were independent predictors of response. CONCLUSION: We identified an intrahepatic transcriptional signature associated with enhanced immune activation which predicts therapy response. These novel associations could lead to better understanding of responsiveness to peginterferon in CHB patients, and may assist in selecting possible responders to interferon-based treatment.


Assuntos
Antivirais/uso terapêutico , Perfilação da Expressão Gênica/métodos , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Fígado/efeitos dos fármacos , Análise de Sequência com Séries de Oligonucleotídeos , Polietilenoglicóis/uso terapêutico , Adenina/análogos & derivados , Adenina/uso terapêutico , Adulto , Biópsia , Distribuição de Qui-Quadrado , Quimioterapia Combinada , Feminino , Marcadores Genéticos , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/genética , Hepatite B Crônica/imunologia , Humanos , Fígado/imunologia , Fígado/metabolismo , Fígado/virologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Organofosfonatos/uso terapêutico , Seleção de Pacientes , Medicina de Precisão , Valor Preditivo dos Testes , Proteínas Recombinantes/uso terapêutico , Reprodutibilidade dos Testes , Fatores de Tempo , Resultado do Tratamento
15.
J Hepatol ; 61(2): 228-34, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24713186

RESUMO

BACKGROUND & AIM: Interferon (IFN) negatively impacts patients' well-being and patient-reported outcomes (PROs). Our aim was to assess PROs during treatment with an IFN-free regimen [sofosbuvir (SOF)+ribavirin (RBV)]. METHODS: Four PRO questionnaires [Short Form-36 (SF-36), Chronic Liver Disease Questionnaire-HCV (CLDQ-HCV), Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F), Work Productivity and Activity Index: Specific Health Problem (WPAI:SHP)] were administered at baseline, end-of-treatment and post-treatment to 334 HCV genotype 2 and 3 patients (naïve or treatment-experienced) enrolled in the VALENCE study. Of these, 250 genotype 3 patients were treated for 24 weeks while 73 genotype 2 and 11 genotype 3 patients received 12 weeks of treatment. RESULTS: Baseline PRO scores were similar between the two arms of the study. Throughout and after treatment, patients receiving 12 or 24 weeks had similar FACIT-F, CLDQ-HCV, SF-36 and WPAI:SHP scores (all p>0.05). Compared to their own baseline scores, patients receiving SOF+RBV experienced modest declines in some aspects of SF-36, CLDQ-HCV, fatigue and WPAI:SHP scores (p = 0.04 to <0.0001). By follow-up week 12, all PRO scores returned to the pre-treatment levels (p>0.05). In patients achieving SVR-12 (regardless of the regimen), significant improvements were noted in general health (p = 0.0004), CLDQ-HCV (p<0.0001), fatigue (p = 0.005), emotional well-being (p<0.0001) and physical component summary score of SF-36 (p = 0.0022). In multivariate analysis, baseline depression, fatigue, insomnia, cirrhosis, and treatment-related adverse events were the most consistent predictors of PRO impairment (all p<0.05). CONCLUSIONS: PROs are minimally impacted by SOF+RBV regimens. An additional 12 weeks of treatment does not substantially add to the PRO burden.


Assuntos
Antivirais/administração & dosagem , Hepatite C Crônica/tratamento farmacológico , Avaliação de Resultados da Assistência ao Paciente , Ribavirina/administração & dosagem , Uridina Monofosfato/análogos & derivados , Idoso , Quimioterapia Combinada , Feminino , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Ribavirina/efeitos adversos , Sofosbuvir , Uridina Monofosfato/administração & dosagem , Uridina Monofosfato/efeitos adversos
16.
J Hepatol ; 61(4): 730-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24824278

RESUMO

BACKGROUND & AIMS: Achievement of HBsAg loss remains the hallmark of chronic hepatitis B treatment. In order to identify host factors contributing to treatment-induced HBsAg loss, we performed a genome-wide screen of single nucleotide polymorphisms (SNPs) and studied its immunological consequence. METHODS: Chronic hepatitis B patients (40 HBeAg-positive and 44 HBeAg-negative) treated with peginterferon alfa-2a and adefovir were genotyped for 999,091 SNPs, which were associated with HBsAg loss at week 96 (n = 9). Plasma carnitine levels were measured by tandem-mass spectrometry, and the effect of carnitine on the proliferative capacity of hepatitis B virus (HBV)-specific and non-specific CD8 T cells was studied in vitro. RESULTS: One polymorphism, rs12356193 located in the SLC16A9 gene, was genome-wide significantly associated with HBsAg loss at week 96 (p = 1.84 × 10(-8)). The previously reported association of rs12356193 with lower carnitine levels was confirmed in our cohort, and baseline carnitine levels were lower in patients with HBsAg loss compared to patients with HBsAg persistence (p = 0.02). Furthermore, we demonstrated that carnitine suppressed HBV-specific CD8 T cell proliferation. CONCLUSIONS: In chronic hepatitis B patients treated with peginterferon and adefovir, we identified strong associations of SLC16A9 gene variation and carnitine levels with HBsAg loss. Our results further suggest that a lower baseline plasma carnitine level increases the proliferative capacity of CD8 T cells, making patients more susceptible to the immunological effect of this treatment. These novel findings may provide new insight into factors involved in treatment-induced HBsAg loss, and play a role in the prediction of treatment outcome.


Assuntos
Adenina/análogos & derivados , Carnitina/sangue , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Hepatite B Crônica , Interferon-alfa/administração & dosagem , Transportadores de Ácidos Monocarboxílicos/genética , Organofosfonatos/administração & dosagem , Polietilenoglicóis/administração & dosagem , Adenina/administração & dosagem , Adulto , Antivirais/administração & dosagem , Linfócitos T CD8-Positivos/imunologia , Quimioterapia Combinada , Feminino , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/sangue , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/genética , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Prognóstico , Proteínas Recombinantes/administração & dosagem , Resultado do Tratamento , Complexo Vitamínico B/sangue
17.
N Engl J Med ; 365(11): 1014-24, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21916639

RESUMO

BACKGROUND: Patients with chronic infection with hepatitis C virus (HCV) genotype 1 often need 48 weeks of peginterferon-ribavirin treatment for a sustained virologic response. We designed a noninferiority trial (noninferiority margin, -10.5%) to compare rates of sustained virologic response among patients receiving two treatment durations. METHODS: We enrolled patients with chronic infection with HCV genotype 1 who had not previously received treatment. All patients received telaprevir at a dose of 750 mg every 8 hours, peginterferon alfa-2a at a dose of 180 µg per week, and ribavirin at a dose of 1000 to 1200 mg per day, for 12 weeks (T12PR12), followed by peginterferon-ribavirin. Patients who had an extended rapid virologic response (undetectable HCV RNA levels at weeks 4 and 12) were randomly assigned after week 20 to receive the dual therapy for 4 more weeks (T12PR24) or 28 more weeks (T12PR48). Patients without an extended rapid virologic response were assigned to T12PR48. RESULTS: Of the 540 patients, a total of 352 (65%) had an extended rapid virologic response. The overall rate of sustained virologic response was 72%. Among the 322 patients with an extended rapid virologic response who were randomly assigned to a study group, 149 (92%) in the T12PR24 group and 140 (88%) in the T12PR48 group had a sustained virologic response (absolute difference, 4 percentage points; 95% confidence interval, -2 to 11), establishing noninferiority. Adverse events included rash (in 37% of patients, severe in 5%) and anemia (in 39%, severe in 6%). Discontinuation of all the study drugs was based on adverse events in 18% of patients overall, as well as in 1% of patients (all of whom were randomly assigned) in the T12PR24 group and 12% of the patients randomly assigned to the T12PR48 group (P<0.001). CONCLUSIONS: In this study, among patients with chronic HCV infection who had not received treatment previously, a regimen of peginterferon-ribavirin for 24 weeks, with telaprevir for the first 12 weeks, was noninferior to the same regimen for 48 weeks in patients with undetectable HCV RNA at weeks 4 and 12, with an extended rapid virologic response achieved in nearly two thirds of patients. (Funded by Vertex Pharmaceuticals and Tibotec; ILLUMINATE ClinicalTrials.gov number, NCT00758043.).


Assuntos
Antivirais/uso terapêutico , Hepatite C/tratamento farmacológico , Oligopeptídeos/uso terapêutico , Adulto , Idoso , Anemia/induzido quimicamente , Antivirais/efeitos adversos , Quimioterapia Combinada , Exantema/induzido quimicamente , Feminino , Hepacivirus/genética , Hepatite C/virologia , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/efeitos adversos , Polietilenoglicóis/uso terapêutico , Proteínas Recombinantes , Ribavirina/uso terapêutico , Adulto Jovem
18.
N Engl J Med ; 362(14): 1292-303, 2010 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-20375406

RESUMO

BACKGROUND: Patients with genotype 1 hepatitis C virus (HCV) who do not have a sustained response to therapy with peginterferon alfa and ribavirin have a low likelihood of success with retreatment. METHODS: We randomly assigned patients with HCV genotype 1 who had not had a sustained virologic response after peginterferon alfa-ribavirin therapy to one of four treatment groups: 115 patients to the T12PR24 group, receiving telaprevir (1125-mg loading dose, then 750 mg every 8 hours) for 12 weeks and peginterferon alfa-2a (180 microg per week) and ribavirin (1000 or 1200 mg per day, according to body weight) for 24 weeks; 113 patients to the T24PR48 group, receiving telaprevir for 24 weeks and peginterferon alfa-2a and ribavirin for 48 weeks (at the same doses as in the T12PR24 group); 111 patients to the T24P24 group, receiving telaprevir and peginterferon alfa-2a for 24 weeks (at the same doses as in the T12PR24 group); and 114 patients to the PR48 (or control) group, receiving peginterferon alfa-2a and ribavirin for 48 weeks (at the same doses as in the T12PR24 group). The primary end point was sustained virologic response (undetectable HCV RNA levels 24 weeks after the last dose of study drugs). RESULTS: The rates of sustained virologic response in the three telaprevir groups--51% in the T12PR24 group, 53% in the T24PR48 group, and 24% in the T24P24 group--were significantly higher than the rate in the control group (14%; P<0.001, P<0.001, and P=0.02, respectively). Response rates were higher among patients who had previously had relapses than among nonresponders. One of the most common adverse events in the telaprevir groups was rash (overall, occurring in 51% of patients, with severe rash in 5%). Discontinuation of study drugs because of adverse events was more frequent in the telaprevir groups than in the control group (15% vs. 4%). CONCLUSIONS: In HCV-infected patients in whom initial peginterferon alfa and ribavirin treatment failed, retreatment with telaprevir in combination with peginterferon alfa-2a and ribavirin was more effective than retreatment with peginterferon alfa-2a and ribavirin alone. (ClinicalTrials.gov number, NCT00420784.)


Assuntos
Antivirais/uso terapêutico , Hepacivirus , Hepatite C Crônica/tratamento farmacológico , Oligopeptídeos/uso terapêutico , Adolescente , Adulto , Idoso , Antivirais/efeitos adversos , Método Duplo-Cego , Quimioterapia Combinada , Exantema/induzido quimicamente , Feminino , Genótipo , Hemoglobinas/análise , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/efeitos adversos , Polietilenoglicóis/uso terapêutico , RNA Viral/sangue , Proteínas Recombinantes , Retratamento , Ribavirina/uso terapêutico , Inibidores de Serina Proteinase/efeitos adversos , Inibidores de Serina Proteinase/uso terapêutico , Falha de Tratamento , Carga Viral/efeitos dos fármacos , Adulto Jovem
19.
J Clin Exp Hepatol ; 12(3): 735-744, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35677522

RESUMO

Background: Currently available treatment options for chronic hepatitis B (CHB) are not recommended for HBeAg-negative patients with a low viral load. These patients may however benefit from treatment by achieving a functional cure, defined by HBsAg-loss and undetectable HBV DNA. This study evaluated the long-term effect of combination treatment with peg-interferon-alpha-2a (peg-IFN) and adefovir or tenofovir compared to no treatment in these patients. Methods: HBeAg-negative CHB patients with HBV-DNA levels < 20,000 IU/mL (n = 151) were previously randomised 1:1:1 for peg-IFN 180 µg/week plus either adefovir 10 mg/day or tenofovir 245 mg/day, or no treatment and treated for 48 weeks in an open-label study. In this prospective long-term follow-up study, patients were monitored yearly up to five years after end of treatment (week 308). The primary outcome was sustained HBsAg-loss and secondary outcome the dynamics of HBsAg and HBV-DNA levels over time. Results: Of the 131 followed patients, the HBsAg-status was known for 118 patients after five-year follow-up. HBsAg-loss occurred similarly (P = 0.703) in all arms: 8/43 (18.6%) peg-IFN + adefovir, 4/34 (11.7%) peg-IFN + tenofovir, and 6/41 (14.6%) among the untreated patients. The time to HBsAg-loss did not differ between groups (P = 0.641). Low baseline HBsAg levels and genotype A were independently associated with HBsAg-loss irrespective of allocation. HBsAg and HBV-DNA levels declined similarly during follow-up in all patient groups. Conclusions: This prospective randomised controlled study showed that HBsAg-loss overtime was not influenced by treatment with a combination of nucleotide analogue and Peg-IFN. Low baseline HBsAg levels can predict HBsAg-loss irrespective of treatment allocation.

20.
Antivir Ther ; 14(4): 591-5, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19578245

RESUMO

BACKGROUND: Telaprevir (TVR) is a hepatitis C virus (HCV) NS3.4A protease inhibitor that has exhibited antiviral activity in patients with HCV genotype 1 infection. The viral dynamics in patients dosed with TVR were compared with those reported for patients treated with interferon (IFN). METHODS: The dynamics of wild-type HCV genotype 1 in patients dosed with TVR monotherapy (n=36) and TVR plus pegylated interferon (PEG-IFN)-alpha2a (n=8) were quantified using a biphasic viral dynamic model. RESULTS: Patients dosed with either TVR monotherapy or TVR plus PEG-IFN-alpha2a had median first and second phase decreases of 12 per day and 1.1 per day, respectively. The second phase decrease was approximately 10-fold higher than reported values for IFN-based treatments (P<0.0001). Patients dosed with TVR plus PEG-IFN-alpha2a had a median remaining viral production after blockage (1-epsilon) of -2.37 log(10). In patients dosed with TVR monotherapy, increased TVR dosage of the same schedule was related to better blockage. CONCLUSIONS: These results suggested that TVR-based regimens for chronic HCV infection will lead to an early and more rapid viral decrease that could potentially result in higher sustained viral response rates as well as offer the potential for a reduced duration of treatment.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Oligopeptídeos/uso terapêutico , Quimioterapia Combinada , Humanos , Interferon beta , Interferons/administração & dosagem , Oligopeptídeos/administração & dosagem , Polietilenoglicóis/administração & dosagem
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