Treatment of hepatitis C

Peginterferon alfa-2a for the treatment of chronic hepatitis C in the era of direct-acting antivirals

BACKGROUND

The availability of novel direct-acting antivirals (DAAs) represents a new era of curative hepatitis C virus (HCV) treatment, with over 95% of patients infected with HCV genotype 1 achieving sustained virological response (SVR). Nevertheless, the majority of patients globally are unable to access these treatments because of cost and infrastructure constraints and, thus, remain untreated and uncured.

DATA SOURCE

Relevant articles of peginterferon (PegIFN)-based treatments in HCV and sofosbuvir-based treatments, simeprevir, daclatasvir/asunaprevir, ritonavir-boosted paritaprevir/ombitasvir/dasabuvir, and grazoprevir/elbasvir, were searched in PubMed database, including general population and special population.

RESULTS

PegIFN in combination with ribavirin remains an important and relevant option for some patients, achieving SVR rates of up to 79% in genotype 1 and 89% in genotype 2 or 3 infections, which increases for patients with favorable IL28B genotypes. Triple therapy of DAA plus PegIFN/ribavirin is effective in treating difficult-to-cure patients infected with HCV genotype 3 or with resistance-associated variants. Owing to its long history in HCV management, the efficacy, tolerability and long-term outcomes associated with PegIFN alfa-2a are well established and have been validated in large-scale studies and in clinical practice for many populations. Furthermore, emerging data show that IFN-induced SVR is associated with lower incidences of hepatocellular carcinoma compared with DAAs. On the contrary, novel DAAs have yet to be studied in special populations, and long-term outcomes, particularly tumor development and recurrence in patients with cirrhosis and/or hepatocellular carcinoma, and reactivation of HBV in dually infected patients, are still unclear.

CONCLUSION

In this interferon-free era, PegIFN-based regimens remain a safe and effective option for selected HCV patients.

Safety and Efficacy of Pegylated Interferon Alpha-2b Monotherapy in Hepatitis C Virus-Infected Children with End-Stage Renal Disease on Hemodialysis

Treatment of hepatitis C virus (HCV) in end-stage renal disease (ESRD) patients is an important issue before kidney transplantation (KT). The aim of the study is to assess the efficacy and tolerability of HCV treatment with pegylated interferon (PEG IFN)-α 2b in children with ESRD. The study included 17 children, aged 3-18 years with ESRD on hemodialysis (HD), with chronic HCV. They received 40 μg/m2 of PEG IFN-α 2b once-weekly subcutaneous injections for 48 weeks. Early virological response (EVR) was achieved in 76.5%. At week 24, 8 patients had negative HCV RNA. Six patients received KT during therapy. Treatment was discontinued in 2 patients: one for anemia and another for retinopathy. Two patients completed 48 weeks of therapy and both achieved end-of-treatment response and sustained virological response (SVR). Constitutional symptoms were the most frequently reported side effects. Neutropenia occurred in 10 patients (58.8%), drop in hemoglobin in 10, and thrombocytopenia in 9. HCV-infected children with ESRD on HD have high EVR (76.5%) on IFN monotherapy. SVR could not be assessed due to the high dropout rate related mainly to early transplantation. Constitutional symptoms and hematological side effects were the most frequently reported side effects.

Relative Expression of Toll-Like Receptors 2 and 7 mRNA in Peripheral Blood of Patients With Hepatitis C

BACKGROUND

Hepatitis C virus (HCV) is an important human pathogen affecting an estimated 120 - 170 million individuals in the world. Toll-Like receptors (TLRs) are pattern-recognition receptors that recognize pathogen-associated molecular patterns, and stimulate immune responses.

OBJECTIVES

The aim of this study was to determine the mRNA expression level of TLR2 and TLR7 in HCV-infected patients in comparison with normal controls.

PATIENTS AND METHODS

Nineteen consecutive patients with HCV infection and nineteen sex and age-matched healthy controls were studied in a case-controlled research.

RESULTS

Our results showed that the expressions of TLR7 in HCV infected samples were significantly increased in comparison those of the controls (P = 0.02), while the expression of TLR2 was similar between the case and the control group (P = 0.8). There were no associations between the expression levels of TLR2 and TLR7 with HCV viral load and HCV genotypes. Also, there was no association between viral load and genotypes of the virus.

CONCLUSIONS

Our findings showed that HCV infection could lead to increased expression level of TLR7 mRNA in peripheral blood cells of HCV infected samples. The viral load and genotypes of HCV did not affect the mRNA expression levels of TLR2 and TLR7.

High-throughput quantitative real-time RT-PCR assay for determining expression profiles of types I and III interferon subtypes

Described in this report is a qRT-PCR assay for the analysis of seventeen human IFN subtypes in a 384-well plate format that incorporates highly specific locked nucleic acid (LNA) and molecular beacon (MB) probes, transcript standards, automated multichannel pipetting, and plate drying. Determining expression among the type I interferons (IFN), especially the twelve IFN-α subtypes, is limited by their shared sequence identity; likewise, the sequences of the type III IFN, especially IFN-λ2 and -λ3, are highly similar. This assay provides a reliable, reproducible, and relatively inexpensive means to analyze the expression of the seventeen interferon subtype transcripts.

Care and treatment of hepatitis C among Aboriginal people in New South Wales, Australia: implications for the implementation of new treatments

INTRODUCTION

Despite Aboriginal Australians being over-represented in populations of people living with hepatitis C (HCV), there is a dearth of research to guide policy and programme development in the area of care and treatment, particularly relating to new HCV treatments.

METHOD

In-depth interviews were conducted with 39 people identifying as Aboriginal Australians and living with HCV in New South Wales.

RESULTS

Participants' experiences were characterised by a lack of detailed or appropriate information provided at diagnosis, high levels of stigma associated with HCV and low overall knowledge of HCV as reported for themselves and their communities. Despite poor diagnosis experiences, participants had undertaken changes to their lifestyle, especially in relation to alcohol use, in order to promote liver health. Concerns about treatment side effects and efficacy impacted participants' decisions to undertake treatment. Eleven participants had undertaken HCV treatment in a variety of care models with a peer worker and in prison.

CONCLUSIONS

The similarities between concerns and experiences of Aboriginal people and other populations living with HCV do not suggest that services and strategies to engage these populations should also be the same. These results suggest that further engagement of the primary care sector in HCV care is important as well as increasing Aboriginal community knowledge of HCV. A variety of service models should be available to meet individuals' preferences, including those offered within Aboriginal community controlled health services emphasising holistic notions of health, and supported by information and communication programmes using principles of health literacy relevant to Aboriginal people.

Ficolin-2 inhibits hepatitis C virus infection, whereas apolipoprotein E3 mediates viral immune escape

Human ficolin-2 (L-ficolin/p35) is a lectin-complement pathway activator that is present in normal human plasma and is associated with infectious diseases; however, little is known regarding the roles and mechanisms of ficolin-2 during chronic hepatitis C virus (HCV) infection. In this study, we found that ficolin-2 inhibits the entry of HCV at an early stage of viral infection, regardless of the viral genotype. Ficolin-2 neutralized and inhibited the initial attachment and infection of HCV by binding to the HCV envelope surface glycoproteins E1 and E2, blocking HCV attachment to low-density lipoprotein receptor (LDLR) and scavenger receptor B1, and weakly interfering with CD81 receptor attachment. However, no interference with claudin-1 and occludin receptor attachment was observed. The C-terminal fibrinogen domain (201-313 aa) of ficolin-2 was identified as the critical binding region for the HCV-E1-E2 N-glycans, playing a critical role in the anti-HCV activity. More importantly, we found that apolipoprotein E (ApoE)3, which is enriched in the low-density fractions of HCV RNA-containing particles, promotes HCV infection and inhibits ficolin-2-mediated antiviral activity. ApoE3, but not ApoE2 and ApoE4, blocked the interaction between ficolin-2 and HCV-E2. Our data suggest that the HCV entry inhibitor ficolin-2 is a novel and promising antiviral innate immune molecule, whereas ApoE3 blocks the effect of ficolin-2 and mediates an immune escape mechanism during chronic HCV infection. HCV may be neutralized using compounds directed against the lipoprotein moiety of the viral particle, and ApoE3 may be a new target to combat HCV infection.

Efficacy and tolerability of low-dose interferon-α in hemodialysis patients with chronic hepatitis C virus infection

AIM: To evaluate the efficacy and tolerability of low-dose standard or pegylated interferon (PEG-IFN) in hepatitis C virus (HCV)-positive hemodialysis patients.

METHODS: In total, 19 patients were enrolled in this study, of which 12 received PEG-IFNα-2a 67.5 μg 1 time/wk (Group 1) and 7 received standard interferon α-2b subcutaneously 1.5 × 10⁶ U 3 times/wk (Group 2). The treatment durations were 48 wk for patients infected with HCV genotype 1 and 24 wk for patients infected with HCV genotype 2/3. All patients were prospectively followed after the completion of therapy. The efficacy and tolerability of the treatment were evaluated based on the sustained virological response (SVR) and treatment-related drop-out rate.

RESULTS: In Group 1, 11 of the 12 patients completed the treatment. Early virological response (EVR) and sustained virological response (SVR) rates were 83.3% and 91.7%, respectively. One patient withdrew from treatment due to an adverse event (leukopenia). The drop-out rate was 8.3% in this group. In Group 2, 5 of the 7 patients completed the treatment with an EVR and SVR of 85.7% and 71.4%, respectively. Two patients withdrew due to treatment-related adverse events (nausea and depression). In this group, the drop-out rate was 28.6%. In total, 16 of the patients attained EVR, and 15 of them completed the treatment. The SVR rate for the patients who attained EVR was 93.7%. Anemia was the most frequent side effect and was observed in 10/19 patients (55.5%), but could be effectively managed with erythropoietin.

CONCLUSION: Low-dose interferon monotherapy, either with PEG-IFNα-2a or standard interferon α-2b, is an effective treatment option for hemodialysis patients with chronic hepatitis C.

How did chronic hepatitis C impact costs related to hospital health care in France in 2009?

AIMS

To evaluate the health care burden of chronic hepatitis C (CHC) in French hospitals.

METHODS

All hospital stays with CHC ICD-10 code were extracted from the 2009 French hospital discharge database and classified in five groups: non-complicated CHC, liver cirrhosis (CIR), hepatocarcinoma (HCC), liver transplantation (LT) and unclassified. Hospital costs were calculated according to the French official prices and expressed in 2010 euro. The economic analysis was carried out from the Social Security point of view.

RESULTS

Twenty-seven thousand two hundred and fifty-eight of the 68,683 hospital stays with CHC ICD-10 code corresponding to 15,482 patients were considered as directly related to HCV: 52% for non-complicated CHC, 33% for CIR, 11% for HCC, 2% for LT and 2% unclassified. The total cost of hospital stays for CHC and its complications was estimated at 65,956,938 €. Almost half (47%) of total costs were attributable to CIR while HCC and LT contributed to 18% and 19%, respectively.

CONCLUSION

This first analysis of the French hospital discharge database focused on CHC brings new and essential information. It shows that 84% of HCV-related hospital costs are attributable to advanced liver diseases. Together with more efficient therapies, enhancing screening and access to treatment policies could substantially relieve the hospital burden of CHC.

Psychological, lifestyle and social predictors of hepatitis C treatment response: a systematic review

BACKGROUND

To increase cure rates for Hepatitis C, barriers to treatment adherence and completion must be identified and overcome.

AIMS

This study systematically reviewed evidence on the psychological, lifestyle and social determinants of achieving viral eradication with antiviral therapy.

METHODS

An electronic search strategy was used to identify relevant studies that examined psychological, lifestyle and social factors related to achieving a sustained virological response (SVR).

RESULTS

Thirty-four studies that matched our criteria were identified. Of the factors that predict response to treatment, Asian ethnicity was an independent predictor of SVR. We found an indirect relationship between diet and SVR, with non-responders to treatment consuming more polyunsaturated fatty acids, fats and carbohydrates than those who attained SVR. The effect of alcohol consumption relied on the amount consumed; fewer than 30 grams daily had no effect on SVR, whereas >70 grams daily had an adverse impact on a patient's ability to achieve SVR, with termination rates up to 44% in those who drank >2 drinks a day. Patients with psychiatric illnesses had comparable SVR rates to controls if they continued psychological therapy (average 42%), although discontinuation rates were high with 11 studies reporting rates from 14 to 48%.

CONCLUSIONS

There are major gaps in current knowledge of the impact of variables such as diet, exercise, attitudes and coping skills on cure rates in chronic Hepatitis C. Those who drink limited amounts of alcohol or have psychiatric disorders should be offered treatment for their disease, with adjunctive education and support to improve treatment completion.

Thyroid disease in chronic hepatitis C infection treated with combination interferon-α and ribavirin: management strategies and future perspective

OBJECTIVE

Hepatitis C virus (HCV) infection is one of the major epidemics afflicting young people in both developed and developing countries. The most common endocrine disorder associated with this infection, especially in conjunction with interferon-α (IFN-α)-based therapy, is thyroid disease (TD). This review examines the development of TD before, during, and after the completion of treatment with combination IFN-α and ribavirin (RBV) for chronic HCV infection. We also summarize the current understanding of the natural history of the condition and propose management and follow-up guidelines.

METHODS

PubMed was searched up to June 30, 2011 for English-language publications that contained the search terms "hepatitis C virus," "chronic hepatitis C," "HCV," "thyroid disease," "thyroiditis," "autoimmunity," "interferon-alpha," and "ribavirin." Additional publications were identified from the reference lists of identified papers. The included studies were original research publications and included combination IFN-α and RBV use in patients that developed TD.

RESULTS

The prevalence of TD before combination IFN-α and RBV therapy ranges from 4.6 to 21.3%; during therapy, 1.1 to 21.3%; and after therapy, 6.7 to 21.3%. The most common TD is thyroiditis. Thyroid function testing (TFT) frequency and diagnostic criteria for various thyroid conditions are not standardized, and many of the existing studies are retrospective.

CONCLUSION

Patients undergoing this therapy should be assessed with a standardized protocol to appropriately detect and manage developed TD. Based on the currently available literature, we recommend that patients receiving combination interferon-α and RBV therapy undergo monthly thyrotropin (TSH) level testing.

Low rates of hepatitis C testing among people who inject drugs in Thailand: implications for peer-based interventions

BACKGROUND

Regular testing for hepatitis C virus (HCV) provides an opportunity for HCV prevention and treatment efforts. In Thailand, the barriers and facilitators of HCV testing among people who inject drugs (IDU) are not known.

METHODS

Using data derived from the Mitsampan Community Research Project between July and October 2011, we assessed the prevalence and factors associated with ever having been tested for HCV antibodies using bivariate statistics and multivariate logistic regression.

RESULTS

Among 427 participants, 141 (33.0%) reported a history of HCV antibody testing. In multivariate analyses, factors positively associated with receiving an HCV antibody test included higher than secondary education [adjusted odds ratio (AOR) = 2.20; 95% confidence interval (CI): 1.35-3.64], binge drug use (AOR = 1.81; 95% CI: 1.12-2.93), methadone treatment enrollment (AOR = 3.47; 95% CI: 1.85-6.95) and having received peer-based education on HCV (AOR = 4.22; 95% CI: 2.66-6.77).

CONCLUSIONS

We found one-third of Thai IDU in our sample reporting a history of HCV testing. The finding that IDU who received peer-based HCV education were more likely to access HCV testing provides evidence for the value of peer-based interventions for this population.

Hepatitis C virus RNA: molecular switches mediated by long-range RNA-RNA interactions?

Multiple conserved structural cis-acting regulatory elements have been recognized both in the coding and untranslated regions (UTRs) of the hepatitis C virus (HCV) genome. For example, the cis-element 5BSL3.2 in the HCV-coding region has been predicted to use both its apical and internal loops to interact with the X RNA in the 3'-UTR, with the IIId domain in the 5'-UTR and with the Alt sequence in the coding region. Additionally, the X RNA region uses a palindromic sequence that overlaps the sequence required for the interaction with 5BSL3.2, to dimerize with another HCV genome. The ability of the 5BSL3.2 and X RNA regions to engage in multi-interactions suggests the existence of one or more molecular RNA switches which may regulate different steps of the HCV life cycle. In this study, we used biophysical methods to characterize the essential interactions of these HCV cis-elements at the molecular level. Our results indicate that X RNA interacts with 5BSL3.2 and another X RNA molecule by adopting two different conformations and that 5BSL3.2 engages simultaneously in kissing interactions using its apical and internal loops. Based on these results, we propose a mode of action for possible molecular switches involving the HCV RNA.

Antiviral effects of small interfering RNA simultaneously inducing RNA interference and type 1 interferon in coxsackievirus myocarditis

Antiviral therapeutics are currently unavailable for treatment of coxsackievirus B3, which can cause life-threatening myocarditis. A modified small interfering RNA (siRNA) containing 5'-triphosphate, 3p-siRNA, was shown to induce RNA interference and interferon activation. We aimed to develop a potent antiviral treatment using CVB3-specific 3p-siRNA and to understand its underlying mechanisms. Virus-specific 3p-siRNA was superior to both conventional virus-specific siRNA with an empty hydroxyl group at the 5' end (OH-siRNA) and nonspecific 3p-siRNA in decreasing viral replication and subsequent cytotoxicity. A single administration of 3p-siRNA dramatically attenuated virus-associated pathological symptoms in mice with no signs of toxicity, and their body weights eventually reached the normal range. Myocardial inflammation and fibrosis were rare, and virus production was greatly reduced. A nonspecific 3p-siRNA showed relatively less protective effect under identical conditions, and a virus-specific OH-siRNA showed no protective effects. We confirmed that virus-specific 3p-siRNA simultaneously activated target-specific gene silencing and type I interferon signaling. We provide a clear proof of concept that coxsackievirus B3-specific 3p-siRNA has 2 distinct modes of action, which significantly enhance antiviral activities with minimal organ damage. This is the first direct demonstration of improved antiviral effects with an immunostimulatory virus-specific siRNA in coxsackievirus myocarditis, and this method could be applied to many virus-related diseases.

Generation of a cell culture-adapted hepatitis C virus with longer half life at physiological temperature

BACKGROUND

We previously reported infectious HCV clones that contain the convenient reporters, green fluorescent protein (GFP) and Renilla luciferase (Rluc), in the NS5a-coding sequence. Although these viruses were useful in monitoring viral proliferation and screening of anti-HCV drugs, the infectivity and yield of the viruses were low.

METHODOLOGY/PRINCIPAL FINDINGS

In order to obtain a highly efficient HCV cultivation system, we transfected Huh7.5.1 cells [1] with JFH 5a-GFP RNA and then cultivated cells for 20 days. We found a highly infectious HCV clone containing two cell culture-adapted mutations. Two cell culture-adapted mutations which were responsible for the increased viral infectivity were located in E2 and p7 protein coding regions. The viral titer of the variant was ∼100-fold higher than that of the parental virus. The mutation in the E2 protein increased the viability of virus at 37°C by acquiring prolonged interaction capability with a HCV receptor CD81. The wild-type and p7-mutated virus had a half-life of ∼2.5 to 3 hours at 37°C. In contrast, the half-life of viruses, which contained E2 mutation singly and combination with the p7 mutation, was 5 to 6 hours at 37°C. The mutation in the p7 protein, either singly or in combination with the E2 mutation, enhanced infectious virus production about 10-50-fold by facilitating an early step of virion production.

CONCLUSION/SIGNIFICANCE

The mutation in the E2 protein generated by the culture system increases virion viability at 37°C. The adaptive mutation in the p7 protein facilitates an earlier stage of virus production, such as virus assembly and/or morphogenesis. These reporter-containing HCV viruses harboring adaptive mutations are useful in investigations of the viral life cycle and for developing anti-viral agents against HCV.

Temporal variations in the hepatitis C virus intrahost population during chronic infection

The intrahost evolution of hepatitis C virus (HCV) holds keys to understanding mechanisms responsible for the establishment of chronic infections and to development of a vaccine and therapeutics. In this study, intrahost variants of two variable HCV genomic regions, HVR1 and NS5A, were sequenced from four treatment-naïve chronically infected patients who were followed up from the acute stage of infection for 9 to 18 years. Median-joining network analysis indicated that the majority of the HCV intrahost variants were observed only at certain time points, but some variants were detectable at more than one time point. In all patients, these variants were found organized into communities or subpopulations. We hypothesize that HCV intrahost evolution is defined by two processes: incremental changes within communities through random mutation and alternations between coexisting communities. The HCV population was observed to incrementally evolve within a single community during approximately the first 3 years of infection, followed by dispersion into several subpopulations. Two patients demonstrated this pattern of dispersion for the rest of the observation period, while HCV variants in the other two patients converged into another single subpopulation after ∼9 to 12 years of dispersion. The final subpopulation in these two patients was under purifying selection. Intrahost HCV evolution in all four patients was characterized by a consistent increase in negative selection over time, suggesting the increasing HCV adaptation to the host late in infection. The data suggest specific staging of HCV intrahost evolution.

Phase 1b study of pegylated interferon lambda 1 with or without ribavirin in patients with chronic genotype 1 hepatitis C virus infection

Interferon lambda 1 (IFN-lambda1) is a type III IFN that produces intracellular responses similar to those of IFN-alpha but in fewer cell types because of differences in the receptor distribution pattern, and this could potentially result in an improved safety profile. This was an open-label three-part study of patients with chronic hepatitis C virus (HCV) genotype 1 infection. Part 1 evaluated single-agent pegylated interferon lambda (PEG-IFN-lambda) at 1.5 or 3.0 microg/kg administered every 2 weeks or weekly for 4 weeks in patients who had relapsed after previous IFN-alpha-based treatment. Part 2 evaluated weekly doses of PEG-IFN-lambda ranging from 0.5 to 2.25 microg/kg in combination with ribavirin (RBV) for 4 weeks in treatment-relapse patients. Part 3 evaluated weekly PEG-IFN-lambda at 1.5 microg/kg in combination with RBV for 4 weeks in treatment-naive patients. Fifty-six patients were enrolled: 24 patients in part 1, 25 patients in part 2, and 7 patients in part 3. Antiviral activity was observed at all PEG-IFN-lambda dose levels (from 0.5 to 3.0 microg/kg). Two of seven treatment-naive patients (29%) achieved rapid virological response. Treatment was well tolerated with minimal flu-like symptoms and no significant hematologic changes other than RBV-associated decreases in hemoglobin. The most common adverse events were fatigue (29%), nausea (12%), and myalgia (11%). Six patients experienced increases in aminotransferases that met protocol-defined criteria for dose-limiting toxicity (DLT) or temporarily holding therapy with PEG-IFN-lambda. Most DLT occurred in patients with high PEG-IFN-lambda exposure.

CONCLUSION

Weekly PEG-IFN-lambda with or without daily RBV for 4 weeks is well tolerated with minimal adverse events and hematologic effects and is associated with clear antiviral activity across a broad range of doses in patients with chronic HCV.

Polo-like kinase 1 is involved in hepatitis C virus replication by hyperphosphorylating NS5A

Hepatitis C virus (HCV) replication involves many viral and host factors. Here, we employed a lentivirus-based RNA interference (RNAi) screening approach to search for possible cellular factors. By using a kinase-phosphatase RNAi library and an HCV replicon reporter system, we identified a serine-threonine kinase, Polo-like kinase 1 (Plk1), as a potential host factor regulating HCV replication. Knockdown of Plk1 reduced both HCV RNA replication and nonstructural (NS) protein production in both HCV replicon cells and HCV-infected cells while it did not significantly affect host cellular growth or cell cycle. Overexpression of Plk1 in the knockdown cells rescued HCV replication. Interestingly, the ratio between the hyperphosphorylated form (p58) and the basal phosphorylated form (p56) of NS5A was lower in the Plk1 knockdown cells and Plk1 kinase inhibitor-treated cells than in the control groups. Further studies showed that Plk1 could be immunoprecipitated together with NS5A. Both proteins partially colocalized in the perinuclear region. Furthermore, Plk1 could phosphorylate NS5A to both the p58 and p56 forms in an in vitro assay system; the phosphorylation efficiency was comparable to that of the reported casein kinase. Taken together, this study shows that Plk1 is an NS5A phosphokinase and thereby indirectly regulates HCV RNA replication. Because of the differential effects of Plk1 on HCV replication and host cell growth, Plk1 could potentially serve as a target for anti-HCV therapy.

An overview about hepatitis C: a devastating virus

Hepatitis C (HCV) is the disease that has affected around 200 million people globally. HCV is a life threatening human pathogen, not only because of its high prevalence and worldwide burden but also because of the potentially serious complications of persistent HCV infection. Chronicity of the disease leads to cirrhosis, hepatocellular carcinoma and end-stage liver disease. HCV positive hepatocytes vary between less than 5% and up to 100%, indicating the high rate of replication of viral RNA. HCV has a very high mutational rate that enables it to escape the immune system. Viral diversity has two levels; the genotypes and Quasiaspecies. Major HCV genotypes constitute genotype 1, 2, 3, 4, 5 and 6 while more than 50 subtypes are known. All HCV genotypes have their particular patterns of geographical distribution and a slight drift in viral population has been observed in some parts of the globe.

HCV drug discovery aimed at viral eradication

Hepatitis C virus (HCV) causes significant morbidity and mortality worldwide with nearly 3% of the world population infected by this virus. Fortunately, this virus does not establish latency, and hence it may be possible to eradicate it. HCV is strongly associated with liver cirrhosis and hepatocellular carcinoma and is currently treated with pegylated interferon-alpha (peg-IFN-alpha) and ribavirin. Unfortunately, these limited treatment options often produce significant side effects, and currently, complete eradication of virus with combined drug modalities has not yet been achieved for the majority of chronically HCV-infected individuals. Restricted treatment options, lack of a universal cure for HCV and the link between chronic infection, liver cirrhosis and hepatocellular carcinoma necessitate design of novel drugs and treatment options. Understanding the relationship between the immune response, viral clearance and inhibition of viral replication with pharmacology-based design can ultimately allow for complete eradication of HCV. This review focuses upon significant novel preclinical and clinical specifically targeted antiviral therapy (STAT-C) drugs under development, highlights their mechanism of action, and discusses their impact on systemic viral loads and permanent clearance of infection.

New strategies for the treatment of hepatitis C virus infection and implications of resistance to new direct-acting antiviral agents

Persistent hepatitis C virus (HCV) infection is a leading cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma and the major indication for liver transplantation in adults. Current standard of care treatment (SOC) with pegylated-interferon-α 2 and ribavirin (RBV) has a limited efficacy and is associated with significant side effects frequently associated with poor compliance or treatment discontinuation, requiring specialized and frequent monitoring. To overcome the limited efficacy of SOC, more than 50 direct-acting antiviral agents (DAA) designed to target viral-encoded proteins essential in the HCV life cycle are currently under development. The rapid selection of resistant mutants associated with the quasispecies nature of HCV with high mutation and replication rates is one of the main challenges for the new HCV therapies. Predictive host and viral factors together with combination of DAAs with or without IFN and/or RBV need to be accurately evaluated to design the most effective individualized treatment strategy within the shortest time interval and with minimum side effects.

Mechanism of hepatitis C virus RNA polymerase inhibition with dihydroxypyrimidines

We studied the biochemical mechanisms associated with inhibition and resistance to a 4,5-dihydroxypyrimidine carboxylate that inhibits the hepatitis C virus (HCV) RNA-dependent RNA polymerase NS5B. On the basis of the structure of the pharmacophore, it has been suggested that these compounds may act as pyrophosphate (PP(i)) mimics. We monitored nucleotide incorporation events during the elongation phase and showed that the polymerase activity of wild-type NS5B was inhibited by the dihydroxypyrimidine at a 50% inhibitory concentration (IC(50)) of 0.73 muM. Enzymes with the G152E or P156L mutation, either of which confers resistance to this compound, showed four- to fivefold increases in IC(50)s. The inhibitor was competitive with respect to nucleotide incorporation. It was likewise effective at preventing the PP(i)-mediated excision of an incorporated chain terminator in a competitive fashion. In the absence of the dihydroxypyrimidine, the reaction was not significantly affected by the G152E or P156L mutation. These data suggest that the resistance associated with these two mutations is unlikely due to an altered interaction with the pyrophosphate-mimicking domain of the compound but, rather, is due to altered interactions with its specificity domain at a region distant from the active site. Together, our findings provide strong experimental evidence that supports the notion that the members of this class of compounds can act as PP(i) mimics that have the potential to mechanistically complement established nucleoside and nonnucleoside analogue inhibitors.

Psychopathological changes and quality of life in hepatitis C virus-infected, opioid-dependent patients during maintenance therapy

AIMS

To examine among maintenance patients (methadone or buprenorphine) with and without hepatitis C virus (HCV) infection (i) the frequency of psychopathological symptoms at baseline and 1-year follow-up; (ii) the association between antiviral interferon (IFN) treatment and psychopathological symptoms; and (iii) to explore whether IFN therapy has an effect on 1-year outcome of maintenance treatment.

DESIGN

Naturalistic prospective longitudinal cohort design.

SETTING

A total of 223 substitution centres in Germany.

PARTICIPANTS

A nationally representative sample of 2414 maintenance patients, namely 800 without and 1614 with HCV infection, of whom 122 received IFN therapy.

MEASURES

HCV infection (HCV+/HCV-), IFN (IFN+/IFN-) treatment status and clinical measures. Diagnostic status and severity (rated by clinician), psychopathology (BSI--Brief Symptom Inventory) and quality of life (EQ-5D--EuroQol Group questionnaire).

FINDINGS

HCV+ patients revealed indications for a moderately increased psychopathological burden and poorer quality of life at baseline and follow-up compared to HCV- patients. HCV+ patients showed a marked deterioration over time only in the BSI subscale somatization (P = 0.002), and the frequency of sleep disorders almost doubled over time (12.8% at baseline; 24.1% at follow-up; P < 0.01). IFN treatment, received by 10% of HCV+ patients, did not impair efficacy or tolerability of maintenance therapy and was associated overall with neither increased psychopathological burden nor reduced quality of life.

CONCLUSIONS

Findings suggest no increased risk among HCV+ patients on maintenance therapy for depressive or other psychopathological syndromes. In our patient sample, IFN treatment was not associated with increased psychopathological burden, reduced quality of life or poorer tolerability and efficacy of maintenance treatment.

Combined therapy of interferon plus ribavirin promotes multiple adaptive solutions in hepatitis C virus

Hepatitis C virus (HCV) presents several regions involved potentially in evading antiviral treatment and host immune system. Two regions, known as PKR-BD and V3 domains, have been proposed to be involved in resistance to interferon. Additionally, hypervariable regions in the envelope E2 glycoprotein are also good candidates to participate in evasion from the immune system. In this study, we have used a cohort of 22 non-responder patients to combined therapy (interferon alpha-2a plus ribavirin) for which samples obtained just before initiation of therapy and after 6 or/and 12 months of treatment were available. A range of 25-100 clones per patient, genome region and time sample were obtained. The predominant amino acid sequences for each time sample and patient were determined. Next, the sequences of the PKR-BD and V3 domains and the hypervariable regions from different time samples were compared for each patient. The highest levels of variability were detected at the three hypervariable regions of the E2 protein and, to a lower extent, at the V3 domain of the NS5A protein. However, no clear patterns of adaptation to the host immune system or to antiviral treatment were detected. In summary, although high levels of variability are correlated to viral adaptive response, antiviral treatment does not seem to promote convergent adaptive changes. Consequently, other regions must be involved in evasion strategies likely based on a combination of multiple mechanisms, in which pools of changes along the HCV genome could confer viruses the ability to overcome strong selective pressures.

Optimal dose of peginterferon and ribavirin for treatment of chronic hepatitis C

Chronic hepatitis C affects 170 million people worldwide, including up to 4 million people in the United States. The current standard of care therapy with pegylated interferon (PEG-IFN) and ribavirin (RBV) while highly successful in patients with genotype 2 and 3 infection, allows for sustained virologic response in 42-46% of treatment-naïve genotype 1 patients, comprising about 70% of cases of chronic hepatitis C in the USA. While awaiting approval of Specifically Targeted Antiviral Therapy for HCV (STAT-C) agents, which will require the completion of additional clinical trials, it is important to optimize the dose and duration of currently available treatment modalities, namely PEG-IFN and RBV, for treatment of CHC. Results of several recent trials evaluating optimal dosing of RBV and higher than standard dosing of PEG-IFN in treatment-naïve genotype 1 patients, as well as data from retreatment trials with "induction" doses of PEG-IFN or high-dose RBV in prior non-responders to IFN-based therapy will be reviewed here. The possibility of shorter duration of therapy for genotype 2 and 3 patients based on recent publications and presentations will be discussed as well.

Antifungal therapy strategies in hematopoietic stem-cell transplant recipients: early treatment options for improving outcomes

Changes in clinical practice permit more patients to undergo hematopoietic stem-cell transplantation but also have increased the risk for invasive fungal infection (IFI) in this population. Given the difficulties in the diagnosis of fungal infection and the correlation between delays in therapy and poor outcome, earlier treatment, and prophylactic strategies are attractive options for the management of IFIs in high-risk patients. The selection of the most effective antifungal treatment strategy requires a thorough knowledge of IFI risk factors, potential causative organisms, and the safety and efficacy of appropriate antifungal agents.

Refined analysis of genetic variability parameters in hepatitis C virus and the ability to predict antiviral treatment response

Hepatitis C virus (HCV) infects approximately 3% of the world population. The chronicity of hepatitis C seems to depend on the level of genetic variability. We have recently (Torres-Puente et al., J Viral Hepat, 2008; 15: 188) reported genetic variability estimates from a large-scale sequence analysis of 67 patients infected with HCV subtypes 1a (23 patients) and 1b (44 patients) and related them to response, or lack of, to alpha-interferon plus ribavirin treatment.. Two HCV genome regions were analysed in samples prior to antiviral therapy, one compressing the three hypervariable regions of the E2 glycoprotein and another one including the interferon sensitive determining region and the V3 domain of the NS5A protein. Haplotype and nucleotide diversity measures showed a clear tendency to higher genetic variability levels in nonresponder than in responder patients. Here, we have refined the analysis of genetic variability (haplotype and nucleotide diversity, number of haplotypes and mutations) by considering their distribution in each of the biologically meaningful subregions mentioned above, as well as in their surrounding and intervening regions. Variability levels are very heterogeneous among the different subregions, being higher for nonresponder patients. Interestingly, significant differences were detected in the biologically relevant regions, but also in the surrounding regions, suggesting that the level of variability of the whole HCV genome, rather than exclusively that from the hypervariable regions, is the main indicator of the treatment response. Finally, the number of haplotypes and mutations seem to be better discriminators than haplotype and nucleotide diversity, especially in the NS5A region.

Neuropsychiatric symptoms of hepatitis C

More than 4 million (2%) people in the United States have been infected with the hepatitis C virus, of whom 2.7 million are chronically infected. The current treatment for chronic hepatitis C patients is Interferon and ribavirin combination therapy, which is associated with numerous neuropsychiatric side effects. The most common are fatigue, depression, cognitive dysfunction, and anxiety. Early identification and treatment of these symptoms may not only improve the patient's mental health, but also may increase the patient's functional ability and overall quality of life. Psychiatric nurses can play a pivotal role in the successful management of the neuropsychiatric symptoms.

Genetic variability in hepatitis C virus and its role in antiviral treatment response

Hepatitis C virus (HCV) is a major health problem worldwide, infecting an estimated 170 million people. The high genetic variability of HCV contributes to the chronicity of hepatitis C. Here, we report results from a large-scale sequence analysis of 67 patients infected with HCV genotype 1, 23 with subtype 1a and 44 with subtype 1b. Two regions of the HCV genome were analysed in samples prior to combined therapy with alpha interferon plus ribavirin, one compressing the hypervariable regions (HVR1, HVR2 and HVR3) of the E2 glycoprotein and another one including the interferon-sensitive determining region (ISDR) and the V3 domain of the NS5A protein. Genetic diversity measures showed a clear tendency to higher genetic variability levels in nonresponder patients to antiviral treatment than in responder patients, although highly disperse values were present within each response group for both subtypes. A more detailed analysis of amino acid composition revealed the presence of several subtype-specific variants in a few positions, but no discriminating positions between responder and nonresponder patients were detected. Our results also revealed that most amino acid positions were highly conserved, especially for subtype 1a. We conclude that the outcome of the antiviral treatment might depend not only on the nature of one or a few independent positions, but more likely on the combination of several positions along the HCV genome. Moreover, the own host's ability to generate an appropriate systemic response, in combination with the action of antivirals, is also likely to be essential for treatment outcome.

Genotyping hepatitis C virus from hemodialysis patients in Central Brazil by line probe assay and sequence analysis

The present study examined the distribution of hepatitis C virus (HCV) genotypes and subtypes in a hemodialysis population in Goiás State, Central Brazil, and evaluated the efficiency of two genotyping methods: line probe assay (LiPA) based on the 5' noncoding region and nucleotide sequencing of the nonstructural 5B (NS5B) region of the genome. A total of 1095 sera were tested for HCV RNA by RT-nested PCR of the 5' noncoding region. The LiPA assay was able to genotype all 131 HCV RNA-positive samples. Genotypes 1 (92.4%) and 3 (7.6%) were found. Subtype 1a (65.7%) was the most prevalent, followed by subtypes 1b (26.7%) and 3a (7.6%). Direct nucleotide sequencing of 340 bp from the NS5B region was performed in 106 samples. The phylogenetic tree showed that 98 sequences (92.4%) were classified as genotype 1, subtypes 1a (72.6%) and 1b (19.8%), and 8 sequences (7.6%) as subtype 3a. The two genotyping methods gave concordant results within HCV genotypes and subtypes in 100 and 96.2% of cases, respectively. Only four samples presented discrepant results, with LiPA not distinguishing subtypes 1a and 1b. Therefore, HCV genotype 1 (subtype 1a) is predominant in hemodialysis patients in Central Brazil. By using sequence analysis of the NS5B region as a reference standard method for HCV genotyping, we found that LiPA was efficient at the genotype level, although some discrepant results were observed at the subtype level (sensitivity of 96.1% for subtype 1a and 95.2% for subtype 1b). Thus, analysis of the NS5B region permitted better discrimination between HCV subtypes, as required in epidemiological investigations.

Interferons at age 50: past, current and future impact on biomedicine

The family of interferon (IFN) proteins has now more than reached the potential envisioned by early discovering virologists: IFNs are not only antivirals with a spectrum of clinical effectiveness against both RNA and DNA viruses, but are also the prototypic biological response modifiers for oncology, and show effectiveness in suppressing manifestations of multiple sclerosis. Studies of IFNs have resulted in fundamental insights into cellular signalling mechanisms, gene transcription and innate and acquired immunity. Further elucidation of the multitude of IFN-induced genes, as well as drug development strategies targeting IFN production via the activation of the Toll-like receptors (TLRs), will almost certainly lead to newer and more efficacious therapeutics. Our goal is to offer a molecular and clinical perspective that will enable IFNs or their TLR agonist inducers to reach their full clinical potential.

Nanomedicines in the treatment of patients with hepatitis C co-infected with HIV--focus on pegylated interferon-alpha

In immuno-competent individuals, the natural course of chronic hepatitis C virus (HCV) infection is highly variable and 5%–30% of patients develop cirrhosis over 20 years. Co-infection with HCV and human immunodeficiency virus (HIV) is an important prognostic factor and associated with more frequent and accelerated progression to cirrhosis. Until recently HIV/AIDS-related complications were life limiting in patients co-infected with HCV; the introduction of highly active antiretroviral treatment (HAART) and the better prognosis of HIV infection has made HCV-related complications an emerging health problem in HCV/HIV co-infected individuals. Treatment of chronic HCV infection has also evolved since the introduction of interferon-alpha. Recently, introduction of pegylated interferon-alpha (peginterferon-alpha) has resulted in an increase in sustained virus clearance rates of up to 80% in selected genotypes and patient populations. The safety and efficacy of modern anti HCV treatment regimens – based on peginterferon-alpha in combination with ribavirin – was evaluated in 4 controlled trials. Sustained clearance of hepatitis C virus can be achieved in up to 35% of patients with HIV/HCV co-infection, and novel HCV treatment regimens based on peginterferon-alpha have no negative effect on the control of HIV disease. In conclusion, if HIV infection is well controlled and CD4⁺ cell counts >100/mm³, treatment of chronic hepatitis C with peginterferon in combination with ribavirin is safe and should be given for 48 weeks regardless of the HCV genotype. Introduction of peginterferon-alpha has significantly improved adherence to treatment and treatment efficacy; in particular sustained virologic response in patients with HCV genotype 1 or 4 infection improved, but sustained viral clearance in only 7%–38% of patients infected with genotype 1 and 4 cannot be the final step in development of effective treatments in patients with HCV/HIV co-infection.

Contribution of insertions and deletions to the variability of hepatitis C virus populations

Little is known about the potential effects of insertions and deletions (indels) on the evolutionary dynamics of hepatitis C virus (HCV). In fact, the consequences of indels on antiviral treatment response are a field of investigation completely unexplored. Here, an extensive sequencing project was undertaken by cloning and sequencing serum samples from 25 patients infected with HCV subtype 1a and 48 patients with subtype 1b. For 23 patients, samples obtained after treatment with alpha interferon plus ribavirin were also available. Two genome fragments containing the hypervariable regions in the envelope 2 glycoprotein and the PKR-BD domain in NS5A were sequenced, yielding almost 16 000 sequences. Our results show that insertions are quite rare, but they are often present in biologically relevant domains of the HCV genome. Moreover, their frequency distributions between different time samples reflect the quasispecies dynamics of HCV populations. Deletions seem to be subject to negative selection.

Chronic hepatitis C virus infection: a review for pharmacists

OBJECTIVE

To review the epidemiology, pathophysiology, and therapeutics of chronic hepatitis C virus (HCV) infection, focusing on patient counseling and adverse effects, to serve as a resource for pharmacists in multiple patient care settings.

DATA SOURCES

Published articles identified through Medline using search terms such as hepatitis C virus, hepacivirus, ribavirin, interferon alfa-2a, or interferon alfa-2b. Therapeutic guidelines retrieved from www.guidelines.gov and the Centers for Disease Control and Prevention (CDC). Additional resources identified from personal bibliographies collected by the author and bibliographies from gathered articles.

STUDY SELECTION

By the author.

DATA EXTRACTION

By the author.

DATA SYNTHESIS

HCV is a blood-borne pathogen affecting an estimated 4 million Americans and 170 million people worldwide. An estimated two-thirds to three-fourths of those infected with HCV have not been diagnosed, and in the next 10 to 20 years, the number of patients diagnosed with HCV is likely to increase. Thus, the health care community, including pharmacists, needs to be educated about the disease, how it is spread, and the details related to treatment of HCV. The standard therapy for HCV is combination therapy with pegylated interferon and ribavirin. This therapy has a varied rate of response that improves with medication adherence. Adherence is often reduced as a result of adverse effects of therapy. In this article, a basic review of HCV is provided, as well as a thorough discussion of strategies to reduce the incidence and severity of adverse effects related to therapy.

CONCLUSION

Pharmacists have an important role in educating other health care practitioners and the community about HCV, providing injection training and medication and adverse effect counseling for patients initiating therapy, and engaging in follow-up and monitoring of patients to encourage therapeutic success by improving medication adherence and patient tolerance of adverse effects.

Pilot study of pegylated interferon-alpha 2a in dialysis patients with chronic hepatitis C virus infection

AIM

Pegylated interferon (PEG-IFN) combined with ribavirin is recommended for the treatment of chronic hepatitis C virus (HCV) infection in patients without renal failure. The optimal treatment of hepatitis C in dialysis patients remains to be established. A high incidence of adverse effects has been observed with conventional interferon and PEG-IFN alpha-2b in dialysis patients.

METHODS

We conducted a prospective study to investigate the tolerability and efficacy of PEG-IFN alpha-2a (135 microg weekly for 48 weeks) in six dialysis patients with chronic HCV infection.

RESULTS

Two patients completed 48 weeks of treatment. Treatment was stopped in three patients (beyond 24 weeks) when they developed unrelated complications, and stopped in one patient due to failure of viral clearance. None required treatment discontinuation due to adverse effects, and PEG-IFN alpha-2a was subjectively well tolerated. Marrow suppression with mild anaemia, leucopenia, or thrombocytopenia remained common. Two patients (infected with genotypes 3a and 1b, respectively) had sustained virological response.

CONCLUSIONS

Results from this pilot study showed that PEG-IFN alpha-2a appeared relatively well tolerated in dialysis patients with chronic HCV infection, and about one-third of patients could achieve sustained virological response.

Treatment of hepatitis C virus infection

Acute and chronic hepatitis C virus (HCV) infection remains a serious health problem worldwide, however, there has been advancement in the treatment of HCV infection due to standard treatment using pegylated interferon and ribavirin. The literature indicates that therapy for HCV is becoming more individualized. In addition to considering genotype and viral RNA levels before treatment, achievement of an early virologic response (EVR) and a rapid virologic response (RVR) is now possible during therapy. Moreover, problem patients, such as non-responders, relapsers, HIV or HBV co-infected patients, patients with liver cirrhosis, and pre- or post-liver transplantation patients are an increasing fraction of the patients requiring treatment. This article reviews the literature regarding standard treatments and problem patients with acute and chronic HCV infection. It also includes discussion on contraindications and side effects of treatment with interferon and ribavirin, as well as new drug development.

Flying Under the Radar: The Immunobiology of Hepatitis C

The hepatitis C virus (HCV) is a remarkably successful pathogen, establishing persistent infection in more than two-thirds of those who contract it. Its success is related to its abilities to blunt innate antiviral pathways and to evade adaptive immune responses. These two themes may be related. We propose that HCV takes advantage of the impaired innate response to delay the organization of an effective adaptive immune attack. The tolerogenic liver environment may provide cover, prolonging this delay. HCV's error-prone replication strategy permits rapid evolution under immune pressure. Persistent high levels of viral antigens may contribute to immune exhaustion. Finally, the virus may benefit from the efficient enlistment of memory T and B cells in the pursuit of a moving target.

Pegylated interferon and ribavirin failures: is retreatment an option?

Currently, there are limited therapeutic options available for chronic hepatitis C (HCV) patients who fail treatment with peginterferon alpha (PEG IFN) + ribavirin (RBV). An option is retreatment with a second course PEG-IFN + RBV. However, the virologic clearance with this option is unknown. Thus, we evaluated the outcome of our cohort of patients with chronic HCV who achieved a sustained viral response when retreated with PEG IFN plus RBV after having no response to an initial course of PEG IFN plus RBV. Nonresponse to treatment was defined as failure to achieve an early virologic response by week 12 or presence of detectable HCV RNA at week 24 or after completion of PEG-IFN + RBV therapy. Twenty patients (12 [60%] men; 8 [40%] women) were treated with PEG IFN alpha-2b plus RBV and PEG IFN alpha-2a plus RBV. The mean age of the patients was 50 years, 85% were white, 95% had genotype 1, and 35% had cirrhosis. Prior to the first course of PEG IFN plus RBV, 12 (60%) of 20 patients had no prior treatment for Hepatitis C. After the second course of PEG IFN plus RBV, 2 (10%) of 20 patients achieved a sustained virologic response. These results suggest marginal benefit of retreatment of patients with chronic HCV with another course of PEG IFN plus RBV after they have not responded to an initial course of PEG IFN plus RBV.

Short-term therapy for patients with hepatitis C virus genotype 2 or 3 infection

In the past 10 years, progress has been made in the management of patients with chronic hepatitis C. A sustained virological response (SVR) is achieved in 80-85% of patients infected with hepatitis C virus (HCV) genotype 2 or 3 after 24 weeks of treatment with peginterferon-alpha and ribavirin. Treatment durations <24 weeks have been investigated to determine whether shorter-term therapy reduces adverse effects and costs compared with longer-term therapy without compromising efficacy. Three studies involving only patients with HCV genotype 2 or 3, with different baseline patient characteristics have shown that 12-16 weeks of treatment can be as effective as 24 weeks of treatment. In all three trials, undetectable HCV RNA 4 weeks after the start of treatment was defined as rapid virological response (RVR), and only patients with RVR stopped treatment early. In the first trial, 75% of patients treated with peginterferon-alpha-2b and ribavirin achieved RVR; these rapid responders achieved an SVR rate of 90% after 14 weeks of treatment. In the second trial, 63% of patients achieved RVR after 4 weeks of treatment with peginterferon-alpha-2b and ribavirin, and 85% of patients with RVR achieved SVR after 12 weeks of treatment. In comparison, 91% of patients with RVR treated for 24 weeks had SVR. In the third study, 93% of the total study population achieved RVR and were randomly assigned to 16 or 24 weeks of treatment with peginterferon-alpha-2a and ribavirin. Among patients with RVR, 85% in the group treated for 16 weeks and 80% in the group treated for 24 weeks achieved SVR. Among patients with HCV genotype 2 or 3, achieving an RVR to interferon-based treatment is common and a criterion to reduce the duration of treatment. In patients with genotype 2 and RVR, 12 weeks of therapy with peginterferon-alpha and ribavirin is recommended. For patients with genotype 3, a univocal recommendation on treatment duration cannot be made. However, ongoing trials will probably clarify this aspect.

Methodological approaches in the assessment of interferon-alfa-induced depression in patients with chronic hepatitis C - a critical review

In recent years, research on interferon (IFN)-induced depressive symptoms in antivirally treated patients suffering from chronic hepatitis C (CHC) has considerably intensified. Profound scientific knowledge of this complication is of great relevance with regard to adherence, compliance, and premature therapy discontinuation. Presently, there is considerable variability of both, the frequency and extent of IFN-induced depression reported in different cohorts of patients. The aim of the presented study was to systematically review recent literature of research within this field; and particularly (1) to identify to what extent methodological bias contributed to inconsistent results in different studies, (2) to critically appraise methods and results of studies published so far, and (3) to suggest directions for future work, especially with respect to alternative and improved methodological approaches. The results of this critical review suggest that the variability of findings seem to be largely due to different study populations, treatment regimens, methodological approaches, and sometimes arbitrary or at least poorly defined choice of screening instruments for depression, particularly criteria for clinically relevant depression (cut-off criteria). Study designs and methodological approaches to investigate IFN-alfa-induced depression in patients with CHC have been incoherent. Future research in this field needs agreement on the use of standardized assessment of IFN-induced depression in CHC. Furthermore, objective criteria and guidelines for the treatment of IFN-induced depression in these patients are needed in clinical practice.

Developing a plan of care using the Roper, Logan and Tierney model

This care study, using the Roper, Logan and Tierney Model of Nursing, examines the presentation of a patient with a history of drug misuse and a current diagnosis of infective endocarditis and hepatitis C. While this particular model of nursing incorporates 12 activities of daily living, this care study will deal with three specific activities: maintaining a safe environment, communication and breathing. One of the main concerns arising from this care study was the inadequate management of pain for the patient. It is suggested in the literature that healthcare professionals do not always adequately address pain management, primarily because of fear of causing addiction. The authors suggest that the patient's history of drug misuse in this study may have further mitigated against him receiving adequate pain control.

Chronic Hepatitis B and C--current treatment and future therapeutic prospects

In chronic hepatitis B treatment with pegylated interferon can now be considered as therapy of choice in both HBeAg positive and HBeAg negative patients and seems to be more effective than lamivudine monotherapy. Alternatively, treatment with lamivudine is able to suppress HBV DNA and to induce HBeAg conversation in up to 30 % of the patients. In HBeAg negative chronic hepatitis B lamivudine has a similar efficiency in suppressing HBV DNA as in HBeAg positive patients. The frequently developing lamivudine resistant HBV variants can now be successfully be treated with adevofir dipivoxil in both forms of chronic hepatitis B. These nucleosides analogues are generally better tolerated than interferon and can also be given in patients with HBV related liver cirrhosis. Our therapeutic armamentarium will be expanded in the near future by other nucleoside analogues such as entecavir, emtricitapine, telbivudine or clevudine. The treatment of choice in chronic hepatitis C currently is pegylated interferon plus ribavirin. This regimen is able to induce a sustained virologic response in 50 % of treatment naïve cases. The limited effectiveness of this therapeutic approach makes additional drugs highly warranted and inhibitors of the NS3-4a protease region or the NS5B polymerase region of the viral genome are under development. In addition, HCV replication inhibitors based on RNA interference (siRNA) or agonists of toll like receptors (TLR), which are part of the inborn immune system recognizing the presence of invading microorganisms, are currently explored as agents active in inhibiting HCV replication. Although none of these drugs are currently licensed for HCV treatment they are promising antiviral candidates for the future.

The contributions of hepatitis B virus and hepatitis C virus infections to cirrhosis and primary liver cancer worldwide

BACKGROUND/AIMS

End-stage liver disease accounts for one in forty deaths worldwide. Chronic infections with hepatitis B virus (HBV) and hepatitis C virus (HCV) are well-recognized risk factors for cirrhosis and liver cancer, but estimates of their contributions to worldwide disease burden have been lacking.

METHODS

The prevalence of serologic markers of HBV and HCV infections among patients diagnosed with cirrhosis or hepatocellular carcinoma (HCC) was obtained from representative samples of published reports. Attributable fractions of cirrhosis and HCC due to these infections were estimated for 11 WHO-based regions.

RESULTS

Globally, 57% of cirrhosis was attributable to either HBV (30%) or HCV (27%) and 78% of HCC was attributable to HBV (53%) or HCV (25%). Regionally, these infections usually accounted for >50% of HCC and cirrhosis. Applied to 2002 worldwide mortality estimates, these fractions represent 929,000 deaths due to chronic HBV and HCV infections, including 446,000 cirrhosis deaths (HBV: n=235,000; HCV: n=211,000) and 483,000 liver cancer deaths (HBV: n=328,000; HCV: n=155,000).

CONCLUSIONS

HBV and HCV infections account for the majority of cirrhosis and primary liver cancer throughout most of the world, highlighting the need for programs to prevent new infections and provide medical management and treatment for those already infected.

Early intervention services for persons with HIV/AIDS and hepatitis C: a community health center perspective

Visiting Nurse Association of Central Jersey has been involved in care for patients with HIV/AIDS since 1991. In that year, the organization received funding as the lead agency for a Title II grant to establish an HIV/AIDS Consortium consisting of over 20 organizations, including other home care agencies, hospitals, county boards of social service, and other community providers. The Consortium collaborated to establish a thorough network of services: housing, transportation, medical treatment, medication access, support, resource identification, and education for both the infected and affected. As the linkages became stronger, the quantity and quality of services increased so that patients were receiving state-of-the-art health care while wrapped in a blanket of comprehensive supportive services.

Histamine dihydrochloride: actions and efficacy in the treatment of chronic hepatitis C infection

The host immune response, in addition to viral factors, is the critical determinant of the pathological consequences of hepatitis C virus infection. Current therapies for genotype 1 are unsuccessful in a substantial number of patients. Histamine dihydrochloride by virtue of its histamine H2 agonistic activity, has the potential to prevent damage induced by oxidative stress in tissues and can protect T and natural killer lymphocytes from oxygen radical-induced functional inhibition and apoptosis, thereby, potentiating interferon-alpha-induced activation of these cells. Coadministration of histamine dihydrochloride and interferon therapy for chronic hepatitis C virus infection was tested in several clinical trials. However, conflicting data and the relatively small numbers of patients enrolled, suggest that this combination should be the focus of further investigation.

Treatment of hepatitis C infection

HCV infection is one of the leading causes of chronic liver disease worldwide,and it results in cirrhosis, liver failure, and HCC. As a result, hepatitis C cirrhosis has become the principal indication for liver transplantation. Ironically,HCV infection can be cured with available antiviral therapies, but only a minority of infected persons has ever been treated. The current standard of therapy isa combination of PEG-IFNalpha and ribavirin, which produces high rates of SVRs(absence of detectable HCV RNA at least 24 weeks after cessation of therapy):42% to 56% in genotype 1 and 75% to 84% in genotypes 2 and 3. Recent reports indicate that the less frequent genotypes 4, 5, and 6 also are responsive to combination therapy. Recommendations for treatment of conventional and special patient populations were reviewed in detail. Newer therapeutics that are entering clinical trials provide hope that SVRs may be possible in patients who are difficult to treat and in nonresponders to current therapy.