Silibinin and related compounds are direct inhibitors of hepatitis C virus RNA-dependent RNA polymerase.

Background & Aims: Silymarin is a mixture of flavonolignans extracted from the milk thistle. Silymarin contains several molecules, including silibinin A, silibinin B, isosilibinin A, isosilibinin B, silicristin, and silidianin. Intravenous infusion of silibinin induces dose-dependent reduction of hepatitis C virus (HCV) RNA levels.

Shortened treatment duration in treatment-naive genotype 1 HCV patients with rapid virological response: a meta-analysis.

Background & Aims: In hepatitis C virus genotype 1 (HCV-1) patients with a rapid viral decline within the first month of therapy, a 24-week course of pegylated interferon (PEG-IFN) alpha and ribavirin treatment has been claimed to be as efficient as the standard 48-week duration.

Methods: We performed a meta-analysis of 7 randomized controlled trials comparing less than 48 weeks to 48 weeks PEG-IFN alpha/ribavirin treatment in 807 HCV-1 patients with rapid viral decline.

Results: SVR was significantly less frequent with short treatment duration than with 48 weeks of therapy, with a mean difference of -13.

Hepatitis C virus proteins induce lipogenesis and defective triglyceride secretion in transgenic mice.

Chronic hepatitis C virus (HCV) infection is associated with altered lipid metabolism and hepatocellular steatosis. Virus-induced steatosis is a cytopathic effect of HCV replication. The goal of this study was to examine the mechanisms underlying HCV-induced lipid metabolic defects in a transgenic mouse model expressing the full HCV protein repertoire at levels corresponding to natural human infection.

Therapeutic implications of hepatitis C virus resistance to antiviral drugs.

Treatment of chronic hepatitis C is currently based on a combination of pegylated interferon-o! and ribavirin. Neither drug exerts direct selective pressure on viral functions, meaning that interferon-a/ribavirin treatment failure is not due to selection of interferon-a- or ribavirin-resistant viral variants. Several novel antiviral approaches are currently in preclinical or clinical development, and most target viral enzymes and functions, such as hepatitis C virus protease and polymerase.

Telaprevir and peginterferon with or without ribavirin for chronic HCV infection.

Background: In patients with chronic infection with hepatitis C virus (HCV) genotype 1, treatment with peginterferon alfa and ribavirin for 48 weeks results in rates of sustained virologic response of 40 to 50%. Telaprevir is a specific inhibitor of the HCV serine protease and could be of value in HCV treatment.

Methods: A total of 334 patients who had chronic infection with HCV genotype 1 and had not been treated previously were randomly assigned to receive one of four treatments involving various combinations of telaprevir (1250 mg on day 1, then 750 mg every 8 hours), peginterferon alfa-2a (180 microg weekly), and ribavirin (dose according to body weight).

Performance of the Abbott real-time PCR assay using m2000sp and m2000rt for hepatitis C virus RNA quantification.

Quantification of hepatitis C virus (HCV) RNA is essential for the everyday management of chronic hepatitis C therapy. "Real-time" PCR techniques are potentially more sensitive than classical PCR techniques, are not prone to carryover contamination, and have a consistently wider dynamic range of quantification. Thus, they are rapidly replacing other technologies for routine quantification of HCV RNA.

Seroconversion to hepatitis C virus alternate reading frame protein during acute infection.

Unlabelled: The existence of hepatitis C virus (HCV) proteins encoded by alternate reading frames overlapping the core-encoding region has been suggested. Several mechanisms of production have been postulated, and the functions of these proteins in the HCV life cycle remain unknown. We analyzed cases of seroconversion to an alternate reading frame protein in a group of 17 patients infected by one of the two HCV genotype 1b strains during an outbreak in a hemodialysis unit.

How to use virological tools for optimal management of chronic hepatitis C.

Chronic hepatitis C is a global health problem that may cause cirrhosis and progression to hepatocellular carcinoma. Currently available antiviral treatments are moderately effective. Several virological assays are available to help diagnose and manage patients infected with the hepatitis C virus (HCV).

Diagnosis and management of chronic viral hepatitis: antigens, antibodies and viral genomes.

Virological tools, including serological and molecular tools, are needed to diagnose chronic hepatitis B and C infections. They may also be useful to establish their prognosis, but they have found their principal application in guiding treatment decisions and assessing the virological responses to therapy. The goal of chronic hepatitis B therapy is to prevent progression of liver disease.

Complex dynamics of hepatitis B virus resistance to adefovir.

Unlabelled: In patients with hepatitis B e antigen-negative chronic hepatitis B, adefovir dipivoxil administration selects variants bearing reverse transcriptase rtN236T and/or rtA181V/T substitutions in 29% of cases after 5 years. The aim of this study was to characterize the dynamics of adefovir-resistant variant populations during adefovir monotherapy in order to better understand the molecular mechanisms underlying hepatitis B virus resistance to this class of nucleotide analogues. Patients included in a 240-week clinical trial of adefovir monotherapy who developed adefovir resistance-associated substitutions were studied.

Interferons and their use in persistent viral infections.

In 2007, the world celebrated the 50th anniversary of the discovery of interferon (IFN) by Isaacs and Lindenmann. Subsequently, the IFN-alpha gene was cloned, fully sequenced and IFN-alpha was produced in recombinant form. Recombinant IFN-alpha is now used as the basis for treatment of chronic hepatitis C virus infection and can also be used to treat certain forms of chronic hepatitis B virus infections.

A non-invasive fibrosis score predicts treatment outcome in chronic hepatitis C virus infection.

Objective: The results of a previous study suggest that an index calculated according to the formula (normalized ASAT x PK-INR) x 100/thrombocyte count (x 10(9)/L; GUCI) may reflect liver fibrosis in patients with chronic hepatitis C virus (HCV) infection. The aims of the present study were (i) to validate the association between the Göteborg University Cirrhosis Index (GUCI) score and liver fibrosis and (ii) to evaluate the utility of this index in predicting the outcome of antiviral treatment.

Material And Methods: A total of 269 patients with chronic HCV infection, stratified according to HCV genotype (1/4 versus 2/3) participated in a phase III trial using pegylated interferon alpha-2a and ribavirin (DITTO study).

Efficacy of serologic marker screening in identifying hepatitis B virus infection in organ, tissue, and cell donors.

Background & Aims: Screens for serologic markers of hepatitis B virus (HBV) are used to prevent its transmission through transplantation. However, exclusion of noninfectious seropositive donors exacerbates graft shortages, and a residual risk of transmission by seronegative donors also exists. This study assessed the risk of HBV associated with different HBV serologic profiles in organ, tissue, and cell transplants, as well as the risk of HBV transmission from seronegative donors.

Determinant roles of environmental contamination and noncompliance with standard precautions in the risk of hepatitis C virus transmission in a hemodialysis unit.

Background: Nosocomial transmission is the second most frequent cause of hepatitis C virus (HCV) infection. A prospective observational study was conducted to assess the roles of environmental contamination and noncompliance with standard precautions in HCV cross-transmission in a hemodialysis unit.

Methods: Patients undergoing chronic hemodialysis in a French university hospital unit were systematically screened, revealing 2 sporadic cases of HCV transmission.

Morphological changes in intracellular lipid droplets induced by different hepatitis C virus genotype core sequences and relationship with steatosis.

Unlabelled: Hepatocellular steatosis is common in patients with chronic hepatitis C. Steatosis can be considered as a true cytopathic lesion induced by hepatitis C virus (HCV) genotype 3, suggesting that one or more viral proteins produced during genotype 3 infection are involved in the steatogenic process, while the same proteins produced during infection by other genotypes are not. We examined in vitro interactions between lipid droplets and full-length core protein isolated from patients with HCV genotype 3a infection, with and without steatosis, and from steatosis-free patients infected by HCV genotype 1b.

Hepatitis C viral kinetics in plasma and peripheral blood mononuclear cells during pegylated interferon-alpha2a/ribavirin therapy.

Background/aims: Analysis of hepatitis C virus (HCV) RNA kinetics in compartments other than plasma may help in understanding HCV replication and identifying clinically significant patterns of treatment response.

Methods: After 6 weeks of pegylated interferon-alpha2a/ribavirin therapy, 74 chronic hepatitis C patients were randomized to individualized or standard treatments for another 42 weeks. HCV RNA was quantified in peripheral blood mononuclear cells (PBMCs) by TaqMan-based real-time PCR and compared to plasma HCV RNA.

Chronic hepatitis B: preventing, detecting, and managing viral resistance.

Licensed oral agents for antiviral therapy in patients with chronic hepatitis B virus (HBV) infection include lamivudine, adefovir, entecavir, and telbivudine. Emtricitabine, tenofovir, and the combination of tenofovir plus emtricitabine in 1 tablet, which are licensed for the treatment of human immunodeficiency virus infection, are additional off-label options for treating HBV infection. Preventing HBV antiviral drug resistance to nucleoside/nucleotide analogues and appropriate management when resistance occurs has become a major focus in the management of chronic hepatitis B.