Home About us Contact
|
Home About us Contact | ||
|
|
||
HCV Therapy (hcv + therapy)
Selected AbstractsGenotype-dependent sensitivity of hepatitis C virus to inhibitors of the p7 ion channel,HEPATOLOGY, Issue 6 2008Stephen Griffin The hepatitis C virus (HCV) p7 protein plays a critical role during particle formation in cell culture and is required for virus replication in chimpanzees. The discovery that it displayed cation channel activity in vitro led to its classification within the "viroporin" family of virus-coded ion channel proteins, which includes the influenza A virus (IAV) M2 protein. Like M2, p7 was proposed as a potential target for much needed new HCV therapies, and this was supported by our finding that the M2 inhibitor, amantadine, blocked its activity in vitro. Since then, further compounds have been shown to inhibit p7 function but the relationship between inhibitory effects in vitro and efficacy against infectious virus is controversial. Here, we have sought to validate multiple p7 inhibitor compounds using a parallel approach combining the HCV infectious culture system and a rapid throughput in vitro assay for p7 function. We identify a genotype-dependent and subtype-dependent sensitivity of HCV to p7 inhibitors, in which results in cell culture largely mirror the sensitivity of recombinant protein in vitro; thus building separate sensitivity profiles for different p7 sequences. Inhibition of virus entry also occurred, suggesting that p7 may be a virion component. Second site effects on both cellular and viral processes were identified for several compounds in addition to their efficacy against p7 in vitro. Nevertheless, for some compounds antiviral effects were specific to a block of ion channel function. Conclusion: These data validate p7 inhibitors as prototype therapies for chronic HCV disease. (HEPATOLOGY 2008;48:1779-1790.) [source] The recent breakthroughs in the understanding of host genomics in hepatitis CEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 10 2010Andri Rauch Eur J Clin Invest 2010; 40 (10): 950,959 Abstract Background, Hepatitis C Virus (HCV) infection is spontaneously resolved in about 30% of acutely infected individuals. In those who progress to chronic hepatitis C, HCV therapy permanently eradicates infection in about 40% of cases. It has long been suspected that host genetic factors are key determinants for the control of HCV infection. Design, We will review in this study four genome-wide association studies (GWAS) and two large candidate gene studies that assessed the role of host genetic variation for the natural and treatment-induced control of HCV infection. Results, The studies consistently identified genetic variation in interleukin 28B (IL28B) as the strongest predictor for the control of HCV infection. Importantly, single nucleotide polymorphisms (SNPs) in IL28B strongly predicted both spontaneous and treatment-induced HCV recovery. IL28B is located on chromosome 19 and encodes interferon-,, a type III interferon with antiviral activity, which is mediated through the JAK-STAT pathway by inducing interferon-stimulated genes. The SNPs identified in the GWAS are in high linkage disequilibrium with coding or functional non-coding SNPs that might modulate function and/or expression of IL28B. The role of the different IL28B alleles on gene expression and cytokine function has not yet been established. Conclusions, These findings provide strong genetic evidence for the influence of interferon-, for both the natural and treatment-induced control of HCV infection, and support the further investigation of interferon-, for the treatment of chronic hepatitis C. Furthermore, genetic testing before HCV therapy could provide important information towards an individualized HCV treatment. [source] Effectiveness of hepatitis C treatment with pegylated interferon and ribavirin in urban minority patients,HEPATOLOGY, Issue 4 2010Paul Feuerstadt Randomized controlled trials of hepatitis C virus (HCV) therapy with pegylated interferon and ribavirin have demonstrated sustained viral response rates (SVRs) of 54%-63% (efficacy). Treatment results in clinical practice (effectiveness) may not be equivalent. The goal of this study was to assess the effectiveness of HCV treatment with pegylated interferon and ribavirin in a treatment-naïve, human immunodeficiency virus (HIV)-negative, United States urban population with many ethnic minority patients. We evaluated 2,370 outpatients for HCV therapy from 2001 to 2006 in the Faculty Practice of the Albert Einstein College of Medicine or the attending-supervised Montefiore Medical Center Liver Clinic. Care was supervised by one experienced physician under conditions of everyday clinical practice, and appropriate ancillary resources were made available to all patients. Two hundred fifty-five patients were treated with a mean age of 50 years (60% male, 40% female; 58% Hispanic, 20% African American, 9% Caucasian, 13% other; 68% genotype 1, the remainder genotypes 2 or 3). Patients had at least one liver biopsy. Intention-to-treat analysis (ITT) showed SVR in 14% of genotype 1 patients and 37% in genotype 2/3 patients (P < 0.001). SVR was significantly higher in faculty practice (27%) than in clinic patients (15%) by intention-to-treat (P = 0.01) but not per-protocol analysis (46% faculty practice, 34% clinic). 3.3% of 1,656 treatment-naïve, HIV antibody,negative individuals ultimately achieved SVR. Current hepatitis C therapies may sometimes be unavailable to, inappropriate for, and ineffective in United States urban patients. Treatment with pegylated interferon and ribavirin was less effective in this population than is implied by multinational phase III controlled trials. New strategies are needed to care for such patients. (HEPATOLOGY 2010.) [source] Growth factors during HCV therapy may be "cost-effective", but are they "effective"?,,HEPATOLOGY, Issue 6 2006Andrew J. Muir M.D., M.H.S. First page of article [source] Enhanced adherence to HCV therapy with higher dose ribavirin formulation: final analyses from the ADHERE registryALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 4 2010I. Alam Aliment Pharmacol Ther 2010; 32: 535,542 Summary Background, Poor adherence to Hepatitis C virus (HCV) treatment is an important cause of treatment failure. Traditional ribavirin 200 mg (RBV) treatment is associated with a significant daily pill burden. RibaPak (RBP), available as 400 mg and 600 mg ribavirin tablets, offers simplified dosing at two pills daily. Aim, To examine whether improved adherence was associated with RBP vs. RBV. Methods, Accurate Dosing in Hepatitis C: Examining the RibaPak Experience (ADHERE) was a U.S., multi-centre, prospective registry capturing data on adherence with RBP vs. RBV in adults with HCV. Adherence was measured by the proportion of subjects remaining on treatment at weeks 4, 12 and 24; by pill counts; and by the proportion of subjects who took ,80% of their prescribed dose. Results A total of 503 patients (RBP = 346, RBV = 157) from 33 sites were included. A greater proportion of RBV vs. RBP subjects prematurely discontinued treatment. At 12 and 24 weeks, a greater proportion of RBP vs. RBV subjects took ,80% of their prescribed doses (P < 0.05). For patients who remained on treatment, the mean milligrams missed per day was significantly greater for RBV vs. RBP at 24 weeks. Conclusions, First line treatment with RBP may offer the best prospect for less discontinuation and improved treatment adherence. [source] Critical role of ribavirin for the achievement of early virological response to HCV therapy in HCV/HIV-coinfected patientsJOURNAL OF VIRAL HEPATITIS, Issue 6 2007B. Ramos Summary., The response to hepatitis C virus (HCV) therapy seems to be lower in HCV/HIV-coinfected patients than in HCV-monoinfected individuals. Given that most pivotal trials conducted in coinfected patients have used the combination of pegylated interferon (pegIFN) along with fixed low doses (800 mg/day) of ribavirin (RBV), it is unclear whether HIV itself and/or suboptimal RBV exposure could explain this poorer outcome. Two well-defined end points of early virological response were evaluated in Peginterferon Ribavirina España Coinfección (PRESCO), a multicentre trial in which the combination of pegIFN plus RBV (1000 mg if body weight <75 kg and 1200 mg if >75 kg) was prescribed to coinfected patients. For comparisons, we used unpublished data from early kinetics in two other large trials, one performed in HIV-negative patients [Pegasys International Study Group (PISG)] in which RBV 1000,1200 mg/day was used and another [AIDS Pegasys Ribavirin Coinfection Trial (APRICOT)] in which HIV-positive patients received fixed low RBV doses (800 mg/day). A total of 348 HCV/HIV-coinfected patients from the PRESCO trial were analysed as well as all patients treated with pegIFN plus RBV, who completed 12 weeks of therapy in the comparative studies (435 in PISG and 268 in APRICOT). Negative serum HCV-RNA at week 4 (which has the highest positive predictive value of sustained virological response, SVR) was attained in 33.3%, 31.2% and 13% of treated patients with HCV genotype 1, respectively, in PRESCO, PISG and APRICOT. For HCV genotypes 2/3, responses were 83.7%, 84.2% and 37%, respectively. A decline lower than 2 log10 at week 12 (which has the highest negative predictive value of SVR) was seen in 25.5%, 19.5% and 37% of HCV genotype-1-infected patients, and in 2.1%, 2.9% and 12% of genotypes-2/3-infected patients, respectively. Prescription of high RBV doses enhances the early virological response to HCV therapy in HCV/HIV-coinfected patients, with results approaching those seen in HCV-monoinfected patients. [source] Pretreatment assessment and predictors of hepatitis C virus treatment in US veterans coinfected with HIV and hepatitis C virusJOURNAL OF VIRAL HEPATITIS, Issue 12 2006L. I. Backus Summary., The US Department of Veterans Affairs (VA) cares for many human immunodeficiency virus/hepatitis C virus (HIV/HCV)-coinfected patients. VA treatment recommendations indicate that all HIV/HCV-coinfected patients undergo evaluation for HCV treatment and list pretreatment assessment tests. We compared clinical practice with these recommendations. We identified 377 HIV/HCV-coinfected veterans who began HCV therapy with pegylated interferon and ribavirin and 4135 HIV/HCV-coinfected veterans who did not but were in VA care at the same facilities during the same period. We compared laboratory and clinical characteristics of the two groups and estimated multivariate logistic regression models of receipt of HCV treatment. Overall, patients had high rates of receipt of tests necessary for HCV pretreatment assessment. Patients starting HCV treatment had higher alanine aminotransferase (ALT), lower creatinine, higher CD4 counts and lower HIV viral loads than patients not starting HCV treatment. In the multivariate model, positive predictors of starting HCV treatment included being non-Hispanic whites, having higher ALTs, lower creatinines, higher HCV viral loads, higher CD4 counts, undetectable HIV viral loads and receiving HIV antiretrovirals. A history of chronic mental illness and a history of hard drug use were negative predictors. Most HIV/HCV-coinfected patients received the necessary HCV pretreatment assessments, although rates of screening for hepatitis A and B immunity can be improved. Having well-controlled HIV disease is by far the most important modifiable factor affecting the receipt of HCV treatment. More research is needed to determine if the observed racial differences in starting HCV treatment reflect biological differences, provider behaviour or patient preference. [source] Apoptosis in hepatitis CJOURNAL OF VIRAL HEPATITIS, Issue 5 2003J. Kountouras Summary. The apoptotic process appears to be a host defence mechanism against viral infections and tumourigenesis. However, many viral genomes encode proteins, which repress apoptosis so as to escape from immune attack by the host. Therefore, virus,host interactions may determine viral persistence, extent and severity of liver inflammation and possibly viral hepatocarcinogenesis. Apoptosis of liver cells may play a significant role in the pathogenesis of hepatitis C. Pathomorphologic features of increased apoptosis include shrinkage and fragmentation of nuclei/cytoplasm in piecemeal necrosis areas, acidophilic bodies, and focal cell dropout in the liver lobule. The hepatitis C virus (HCV) core protein exhibits both proapoptotic or antiapoptotic actions. Modulation of apoptosis may involve binding of HCV core protein to the intracellular signal transducing portion of death receptors and displacement of signalling molecules. Apoptosis may occur in the absence of significant transaminase elevation, thereby explaining the lack of correlation between biochemical activity and liver cell histological injury. Monitoring caspase activation might provide a reliable tool to estimate the efficacy of HCV therapy, and might open challenging therapeutic strategies in HCV infection. The antiviral effect of interferon may be mediated through induction of apoptosis. Lastly, administration of the antiapoptotic ursodeoxycholic acid in HCV infection is compatible with the notion that apoptosis may represent a mechanism for viral shedding rather than for viral elimination, thereby raising the concept that inhibition of apoptosis could ameliorate hepatitis C. [source] Comparison of characteristics of treated and non-treated patients with Hepatitis C infection,PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 2 2006C. Bradley Hare MD Abstract Objectives This study compares the characteristics of treated and non-treated patients with Hepatitis C (HCV) infection. Methods Information on patient demographics, clinical data, and treatment regimens were collected from a retrospective medical record review of 998 patients diagnosed with HCV, representing a diverse geographic sample of 200 U.S. physicians including 130 gastroenterologists, 50 infectious disease physicians, and 20 hepatologists. A total of 551 patients were randomly selected and 447 were provided as an augmented sample in an intent-to-treat analysis based on treatment decisions. Pretreatment factors examined included age, gender, race, weight, HCV genotype, HCV viral load, serum ALT levels, liver biopsy results, cirrhosis, HIV co-infection, HBV co-infection, IV drug use, and insurance status. Univariate analyses were performed using Chi-squared or ANOVA tests. Factors that were significant in univariate analyses were entered into a multivariate logistic regression model with HCV treatment as the outcome variable. Results Of the 998 patients reviewed, 778 were treated for HCV and 220 were not treated. In univariate analyses, non-treated patients were more likely to be African American, HBV co-infected, HIV co-infected, IDUs, alcoholics, Medicaid insured, and were less likely to have had biopsies. The multivariate regression analysis demonstrated that performance of a liver biopsy, treatment with psychiatric medications (antidepressants and anxiolytics), and patient weight were independently associated with treatment, while Medicaid insurance and HIV co-infection were independently associated with a decreased likelihood of receiving HCV therapy. Conclusion This study suggests that it is not the clinical stage of HCV infection but the patient's demographic characteristics and co-morbid conditions that impact the decision to initiate HCV therapy. Copyright © 2005 John Wiley & Sons, Ltd. [source] | ||||||||||