47 resultados para Interferon treatment

em Université de Lausanne, Switzerland


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Vaniprevir (MK-7009) is a macrocyclic hepatitis C virus (HCV) nonstructural protein 3/4A protease inhibitor. The aim of the present phase II study was to examine virologic response rates with vaniprevir in combination with pegylated interferon alpha-2a (Peg-IFN-α-2a) plus ribavirin (RBV). In this double-blind, placebo-controlled, dose-ranging study, treatment-naïve patients with HCV genotype 1 infection (n = 94) were randomized to receive open-label Peg-IFN-α-2a (180 μg/week) and RBV (1,000-1,200 mg/day) in combination with blinded placebo or vaniprevir (300 mg twice-daily [BID], 600 mg BID, 600 mg once-daily [QD], or 800 mg QD) for 28 days, then open-label Peg-IFN-α-2a and RBV for an additional 44 weeks. The primary efficacy endpoint was rapid viral response (RVR), defined as undetectable plasma HCV RNA at week 4. Across all doses, vaniprevir was associated with a rapid two-phase decline in viral load, with HCV RNA levels approximately 3 log(10) IU/mL lower in vaniprevir-treated patients, compared to placebo recipients. Rates of RVR were significantly higher in each of the vaniprevir dose groups, compared to the control regimen (68.8%-83.3% versus 5.6%; P < 0.001 for all comparisons). There were numerically higher, but not statistically significant, early and sustained virologic response rates with vaniprevir, as compared to placebo. Resistance profile was predictable, with variants at R155 and D168 detected in a small number of patients. No relationship between interleukin-28B genotype and treatment outcomes was demonstrated in this study. The incidence of adverse events was generally comparable between vaniprevir and placebo recipients; however, vomiting appeared to be more common at higher vaniprevir doses. CONCLUSION: Vaniprevir is a potent HCV protease inhibitor with a predictable resistance profile and favorable safety profile that is suitable for QD or BID administration.

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BACKGROUND & AIMS: The host immune response during the chronic phase of hepatitis C virus infection varies among individuals; some patients have a no interferon (IFN) response in the liver, whereas others have full activation IFN-stimulated genes (ISGs). Preactivation of this endogenous IFN system is associated with nonresponse to pegylated IFN-α (pegIFN-α) and ribavirin. Genome-wide association studies have associated allelic variants near the IL28B (IFNλ3) gene with treatment response. We investigated whether IL28B genotype determines the constitutive expression of ISGs in the liver and compared the abilities of ISG levels and IL28B genotype to predict treatment outcome. METHODS: We genotyped 109 patients with chronic hepatitis C for IL28B allelic variants and quantified the hepatic expression of ISGs and of IL28B. Decision tree ensembles, in the form of a random forest classifier, were used to calculate the relative predictive power of these different variables in a multivariate analysis. RESULTS: The minor IL28B allele was significantly associated with increased expression of ISG. However, stratification of the patients according to treatment response revealed increased ISG expression in nonresponders, irrespective of IL28B genotype. Multivariate analysis of ISG expression, IL28B genotype, and several other factors associated with response to therapy identified ISG expression as the best predictor of treatment response. CONCLUSIONS: IL28B genotype and hepatic expression of ISGs are independent predictors of response to treatment with pegIFN-α and ribavirin in patients with chronic hepatitis C. The most accurate prediction of response was obtained with a 4-gene classifier comprising IFI27, ISG15, RSAD2, and HTATIP2.

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BACKGROUND AND STUDY AIMS: This was an observational, non-interventional, multicenter, phase IV study, in patients with genotype 1/4/5/6 chronic hepatitis C (CHC). The primary objectives were to evaluate SVR in patients with no or minimal fibrosis (METAVIR F0-F1) versus well established fibrosis (F2-F4), and to estimate response on Weeks 12, 24 and 48 on treatment in previously untreated patients with genotypes 1/4/5/6 CHC. PATIENTS AND METHODS: 538 patients treated with pegylated interferon alfa 2b 1.5 mcg/kg in combination with ribavirin 800-1200 mg/day were enrolled in 55 sites in Belgium and Luxembourg, 505 being considered for the analysis. 40% of the patients were female and 60% male, the average age was 47.5 years, 10.5% were 65 or older. RESULTS: SVR was observed in 35% of the patients, EVR in 68%, of which pEVR in 33% and cEVR in 35%. SVR was observed in 43% of the low fibrosis group (F0, F1) and 30% of the high fibrosis group (F2, F3, F4) (p = 0.005). SVR rates were 34% for genotype 1, 37% for genotype 4, and 47% for genotype 5 (NS). Multivariate analysis showed that EVR and baseline METAVIR score are independent prognostic factors for SVR. CONCLUSIONS: This trial confirms that fibrosis stage and early viral response are the most important key-factors to predict sustained response, suggesting that the earlier patients are treated, the better the outcome. Non-invasive techniques enable us to closely monitor progression of fibrosis, allowing a better selection of patients for antiviral treatment in the DAA-era.

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Aims: Recently, several clinical trials analyzed if extended duration of treatment with pegylated interferon-alfa and ribavirin over 48 weeks can improve sustained virologic response (SVR) rates in HCV genotype 1-infected patients with slow virologic response. Because results of these clinical trials are conflicting, we performed a metaanalysis to determine the overall impact of extended treatment compared to standard treatment on virologic response rates in treatment-naive HCV genotype 1 slow responders. Methods: Literature search was performed independently by two observers using Pub Med, EMBASE, CENTRAL and abstracts presented in English at international liver and gastroenterology meetings. Randomized controlled clinical trials (RCTs; but studies that re-analyzed data retrospectively RCTs were also allowed) were considered if they included monoinfected treatment-naive HCV genotype 1 patients and compared treatment with pegIFN-alfa 2a or 2b in combination with ribavirin for 48 weeks versus extended treatment (up to 72 weeks) in slow responders. Primary and secondary end points were SVR rates and end-of-treatment (EOT) and relapse rates, respectively. In the present meta-analysis, study endpoints were summarized with a DerSimonian-Laird estimate for binary outcome basing on a random effects model. Results: Literature search yielded seven RTCs addressing the benefit of extended treatment with pegylated interferon-alfa and ribavirin in treatment-naive HCV genotype 1 slow responders. In total, 1330 slow responders were included in our meta-analysis. We show that extended treatment duration compared to the standard of care significantly improves SVR rates in HCV genotype 1 slow responders (12.4% improvement of overall SVR rate, 95% CI 0.055- 0.193, P = 0.0005). In addition, we show that rates of viral relapse were significantly reduced by extended treatment (24.1% reduction of relapse, 95% CI −0.3332 to −0.1487, P < 0.0001), whereas no significant impact of extended treatment on EOT response rates was found. Though extended treatment was burdened with an enhanced rate of premature treatment discontinuation due to interferonalfa- and ribavirin-related side effects, the frequency of serious adverse events was not increased. Conclusions: Treatment extension in HCV genotype 1 slow responders can improve SVR rates in difficult to treat patients and should be considered in patients who need to be treated before specific antivirals will be approved.

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Background and aim: Recurrent hepati tis C is a major cause of morbidity and mortality after li ver transpl ant ati on (LT), and optimal treatm ent algorithms have yet to be defined. Here, we present our experience of 22 patients with recurrent hepatitis C treated in our institution .Patients and methods: Twenty-two patients with hi stology-proven recurrent hepati tis Cafter LT were treated since 2003. Treatment was ini ti ated with pegylated interferon-a2a 135 IIg per week and ribavirin 400 mg per day in the majority of patients, and subsequent doses were adapted individllally based on on-treatment virologieal responses and c1inical and/or biochemical si de effeets.Results: On an intention-to-treat basis, ustained virological re ponse(SVR) was achieved in 12/21 (54.5%) patie nts (5/12 [41 .6%], 2/3 [67%], 4/5 [80%] and 1/2 [50%] of patients infected with genotypes 1,2,3 and 4, respectively). Two patients experieneed relap e and 6 did not respond to treatm ent (NR). Treatment duration ranged from 24 to 90 weeks. It was stopped prematurely due to adverse events in 6/22 (27.2%) patients (with SVR achieved in 2 patients, NR in 2 patients, and death of 2 patients: one patient awaiting retransplantation and a second patient with HCV-HJV co-infection and fibrosing cholestat ic hepatiti s, nine months after transplantation). Of note, SVR was achi eved in a patient \Vi th combined liver and kidney transplantation. Importantly, SVR \Vas ach ieved in some patients despite the lack ofan early virological response or HCV RNA negativity at week 24. Darbepoetin a and fil ~,'rasti m were used in 36% and 18%, respectively.Conclusion: Individually adapted treatment of recurrent hepatitis C canachieve SVR in a substantial proponion ofLT patients. Conventional stopping rules do not apply in this setting so that prolonged therapy may be useful in selected patients.

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Hepatitis C virus (HCV) infection is a major cause of chronic liver disease worldwide. The current standard therapy for chronic hepatitis C (CHC) consists of a combination of pegylated IFN alpha (pegIFNalpha) and ribavirin. It achieves a sustained viral clearance in only 50-60% of patients. To learn more about molecular mechanisms underlying treatment failure, we investigated IFN-induced signaling in paired liver biopsies collected from CHC patients before and after administration of pegIFNalpha. In patients with a rapid virological response to treatment, pegIFNalpha induced a strong up-regulation of IFN-stimulated genes (ISGs). As shown previously, nonresponders had high expression levels of ISGs before therapy. Analysis of posttreatment biopsies of these patients revealed that pegIFNalpha did not induce expression of ISGs above the pretreatment levels. In accordance with ISG expression data, phosphorylation, DNA binding, and nuclear localization of STAT1 indicated that the IFN signaling pathway in nonresponsive patients is preactivated and refractory to further stimulation. Some features characteristic of nonresponders were more accentuated in patients infected with HCV genotypes 1 and 4 compared with genotypes 2 and 3, providing a possible explanation for the poor response of the former group to therapy. Taken together with previous findings, our data support the concept that activation of the endogenous IFN system in CHC not only is ineffective in clearing the infection but also may impede the response to therapy, most likely by inducing a refractory state of the IFN signaling pathway.

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Interferon-gamma (IFN-gamma) modulates the expression of Class II major histocompatibility antigens (MHC), thus providing a potential regulatory mechanism for local immune reactivity in the context of MHC-restricted antigen presentation. Within the central nervous system (CNS), the expression of MHC Class II antigens has been demonstrated on human reactive astrocytes and glioma cells. In order to investigate the modulation of HLA-DR on normal astrocytes, two cell lines were grown from a 20-week-old fetal brain. In situ none of the fetal brain cells expressed HLA-DR as determined by immunohistology on frozen tissue sections. The two cell lines, FB I and FB II, expressed GFAP indicating their astrocytic origin. FB I was HLA-DR negative at the first tissue culture passages, but could be induced to express HLA-DR when treated with 500 U/ml IFN-gamma. FB II was spontaneously HLA-DR positive in the early passages, lost the expression of this antigen after 11 passages and could also be induced to express HLA-DR by IFN-gamma. The induction of HLA-DR expression was demonstrated both by a binding RIA and by immunoprecipitation using a monoclonal antibody (MAB) directed against a monomorphic determinant of HLA-DR. The HLA-DR alloantigens were determined on FB II cells after IFN-gamma treatment, by immunofluorescence and by cytotoxicity assays, and were shown to be DR4, DR6, Drw52, DRw53 and DQwl. These results show that human fetal astrocytes can be induced to express HLA-DR by IFN-gamma in vitro and support the concept that astrocytes may function as antigen-presenting cells.

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Background: Therapy of chronic hepatitis C (CHC) with pegIFNa/ribavirin achieves sustained virologic response (SVR) in ~55%. Pre-activation of the endogenous interferon system in the liver is associated non-response (NR). Recently, genome-wide association studies described associations of allelic variants near the IL28B (IFNλ3) gene with treatment response and with spontaneous clearance of the virus. We investigated if the IL28B genotype determines the constitutive expression of IFN stimulated genes (ISGs) in the liver of patients with CHC. Methods: We genotyped 93 patients with CHC for 3 IL28B single nucleotide polymorphisms (SNPs, rs12979860, rs8099917, rs12980275), extracted RNA from their liver biopsies and quantified the expression of IL28B and of 8 previously identified classifier genes which discriminate between SVR and NR (IFI44L, RSAD2, ISG15, IFI22, LAMP3, OAS3, LGALS3BP and HTATIP2). Decision tree ensembles in the form of a random forest classifier were used to calculate the relative predictive power of these different variables in a multivariate analysis. Results: The minor IL28B allele (bad risk for treatment response) was significantly associated with increased expression of ISGs, and, unexpectedly, with decreased expression of IL28B. Stratification of the patients into SVR and NR revealed that ISG expression was conditionally independent from the IL28B genotype, i.e. there was an increased expression of ISGs in NR compared to SVR irrespective of the IL28B genotype. The random forest feature score (RFFS) identified IFI27 (RFFS = 2.93), RSAD2 (1.88) and HTATIP2 (1.50) expression and the HCV genotype (1.62) as the strongest predictors of treatment response. ROC curves of the IL28B SNPs showed an AUC of 0.66 with an error rate (ERR) of 0.38. A classifier with the 3 best classifying genes showed an excellent test performance with an AUC of 0.94 and ERR of 0.15. The addition of IL28B genotype information did not improve the predictive power of the 3-gene classifier. Conclusions: IL28B genotype and hepatic ISG expression are conditionally independent predictors of treatment response in CHC. There is no direct link between altered IFNλ3 expression and pre-activation of the endogenous system in the liver. Hepatic ISG expression is by far the better predictor for treatment response than IL28B genotype.

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BACKGROUND & AIMS: Hepatitis C virus (HCV) induces chronic infection in 50% to 80% of infected persons; approximately 50% of these do not respond to therapy. We performed a genome-wide association study to screen for host genetic determinants of HCV persistence and response to therapy. METHODS: The analysis included 1362 individuals: 1015 with chronic hepatitis C and 347 who spontaneously cleared the virus (448 were coinfected with human immunodeficiency virus [HIV]). Responses to pegylated interferon alfa and ribavirin were assessed in 465 individuals. Associations between more than 500,000 single nucleotide polymorphisms (SNPs) and outcomes were assessed by multivariate logistic regression. RESULTS: Chronic hepatitis C was associated with SNPs in the IL28B locus, which encodes the antiviral cytokine interferon lambda. The rs8099917 minor allele was associated with progression to chronic HCV infection (odds ratio [OR], 2.31; 95% confidence interval [CI], 1.74-3.06; P = 6.07 x 10(-9)). The association was observed in HCV mono-infected (OR, 2.49; 95% CI, 1.64-3.79; P = 1.96 x 10(-5)) and HCV/HIV coinfected individuals (OR, 2.16; 95% CI, 1.47-3.18; P = 8.24 x 10(-5)). rs8099917 was also associated with failure to respond to therapy (OR, 5.19; 95% CI, 2.90-9.30; P = 3.11 x 10(-8)), with the strongest effects in patients with HCV genotype 1 or 4. This risk allele was identified in 24% of individuals with spontaneous HCV clearance, 32% of chronically infected patients who responded to therapy, and 58% who did not respond (P = 3.2 x 10(-10)). Resequencing of IL28B identified distinct haplotypes that were associated with the clinical phenotype. CONCLUSIONS: The association of the IL28B locus with natural and treatment-associated control of HCV indicates the importance of innate immunity and interferon lambda in the pathogenesis of HCV infection.

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The antiviral potency of the cytokine IFN-α has been long appreciated but remains poorly understood. A number of studies have suggested that induction of the apolipoprotein B mRNA editing enzyme, catalytic polypeptide 3 (APOBEC3) and bone marrow stromal cell antigen 2 (BST-2/tetherin/CD317) retroviral restriction factors underlies the IFN-α-mediated suppression of HIV-1 replication in vitro. We sought to characterize the as-yet-undefined relationship between IFN-α treatment, retroviral restriction factors, and HIV-1 in vivo. APOBEC3G, APOBEC3F, and BST-2 expression levels were measured in HIV/hepatitis C virus (HCV)-coinfected, antiretroviral therapy-naïve individuals before, during, and after pegylated IFN-α/ribavirin (IFN-α/riba) combination therapy. IFN-α/riba therapy decreased HIV-1 viral load by -0.921 (±0.858) log(10) copies/mL in HIV/HCV-coinfected patients. APOBEC3G/3F and BST-2 mRNA expression was significantly elevated during IFN-α/riba treatment in patient-derived CD4+ T cells (P < 0.04 and P < 0.008, paired Wilcoxon), and extent of BST-2 induction was correlated with reduction in HIV-1 viral load during treatment (P < 0.05, Pearson's r). APOBEC3 induction during treatment was correlated with degree of viral hypermutation (P < 0.03, Spearman's ρ), and evolution of the HIV-1 accessory protein viral protein U (Vpu) during IFN-α/riba treatment was suggestive of increased BST-2-mediated selection pressure. These data suggest that host restriction factors play a critical role in the antiretroviral capacity of IFN-α in vivo, and warrant investigation into therapeutic strategies that specifically enhance the expression of these intrinsic immune factors in HIV-1-infected individuals.

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BACKGROUND: Vitamin D is an important immune modulator and preliminary data indicated an association between vitamin D deficiency and sustained virologic response (SVR) rates in patients with chronic hepatitis C. We therefore performed a comprehensive analysis on the impact of vitamin D serum levels and of genetic polymorphisms within the vitamin D cascade on chronic hepatitis C and its treatment. METHODS: Vitamin D serum levels, genetic polymorphisms within the vitamin D receptor and the 1α- hydroxylase were determined in a cohort of 468 HCV genotype 1, 2 and 3 infected patients who were treated with interferon-alfa based regimens. RESULTS: Chronic hepatitis C was associated with a high incidence of severe vitamin D deficiency compared to controls (25(OH)D3<10 ng/mL in 25% versus 12%, p<0.00001), which was in part reversible after HCV eradication. 25(OH)D3 deficiency correlated with SVR in HCV genotype 2 and 3 patients (63% and 83% SVR for patients with and without severe vitamin D deficiency, respectively, p<0.001). In addition, the CYPB27-1260 promoter polymorphism rs10877012 had substantial impact on 1-25- dihydroxyvitamin D serum levels and SVR rates in HCV genotype 1, 2 and 3 infected patients. CONCLUSIONS: Chronic hepatitis C virus infection is associated with vitamin D deficiency. Reduced 25- hydroxyvitamin D levels and CYPB27-1260 promoter polymorphism are associated with failure to achieve SVR in HCV genotype 1, 2, 3 infected patients.

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Recent studies have demonstrated the immunomodulatory properties of vitamin D, and vitamin D deficiency may be a risk factor for the development of MS. The risk of developing MS has, in fact, been associated with rising latitudes, past exposure to sun and serum vitamin D status. Serum 25-hydroxyvitamin D [25(OH)D] levels have also been associated with relapses and disability progression. The identification of risk factors, such as vitamin D deficiency, in MS may provide an opportunity to improve current treatment strategies, through combination therapy with established MS treatments. Accordingly, vitamin D may play a role in MS therapy. Small clinical studies of vitamin D supplementation in patients with MS have reported positive immunomodulatory effects, reduced relapse rates and a reduction in the number of gadolinium-enhancing lesions. However, large randomized clinical trials of vitamin D supplementation in patients with MS are lacking. SOLAR (Supplementation of VigantOL(®) oil versus placebo as Add-on in patients with relapsing-remitting multiple sclerosis receiving Rebif(®) treatment) is a 96-week, three-arm, multicenter, double-blind, randomized, placebo-controlled, Phase II trial (NCT01285401). SOLAR will evaluate the efficacy of vitamin D(3) as add-on therapy to subcutaneous interferon beta-1a in patients with RRMS. Recruitment began in February 2011 and is aimed to take place over 1 calendar year due to the potential influence of seasonal differences in 25(OH)D levels.