Possible mechanisms of action and reasons for failure of antiviral therapy in chronic hepatitis C

Association of chronic inflammation and perceived stress with abnormal functional connectivity in brain areas involved with interoception in hepatitis C patients

BACKGROUND

Sickness behavioral changes elicited by inflammation may become prolonged and dysfunctional in patients with chronic disease, such as chronic hepatitis C (CHC). Neuroimaging studies show that the basal ganglia and insula are sensitive to systemic inflammation.

AIM

To elucidate the clinical and neurobiological aspects of prolonged illnesses in patients with CHC.

METHODS

Thirty-five CHC patients not treated with interferon-α or other antiviral therapy, and 30 control subjects matched for age and sex, were evaluated for perceived stress (perceived stress scale; PSS), depression (PHQ-9), fatigue and irritability through a visual analog scale (VAS), as well as serum levels of interleukin-6 (IL-6), prostaglandin E₂ (PGE₂) and oxidative stress markers. Functional MRI was performed, measuring resting-state functional connectivity using a region-of-interest (seed)-based approach focusing on the bilateral insula, subgenual anterior cingulate cortex and bilateral putamen. Between-group differences in functional connectivity patterns were assessed with two-sample t-tests, while the associations between symptoms, inflammatory markers and functional connectivity patterns were analyzed with multiple regression analyses.

RESULTS

CHC patients had higher PSS, PHQ-9 and VAS scores for fatigue and irritability, as well as increased IL-6 levels, PGE₂ concentrations and antioxidant system activation compared to controls. PSS scores positively correlated with functional connectivity between the right anterior insula and right putamen, whereas PHQ-9 scores correlated with functional connectivity between most of the seeds and the right anterior insula. PGE₂ (positively) and IL-6 (negatively) correlated with functional connectivity between the right anterior insula and right caudate nucleus and between the right ventral putamen and right putamen/globus pallidus. PGE₂ and PSS scores accounted for 46% of the variance in functional connectivity between the anterior insula and putamen.

CONCLUSIONS

CHC patients exhibited increased perceived stress and depressive symptoms, which were associated with changes in inflammatory marker levels and in functional connectivity between the insula and putamen, areas involved in interoceptive integration, emotional awareness, and orientation of motivational state.

Hepatitis C virus infection, and neurological and psychiatric disorders - A review

An association between hepatitis C virus infection and neuropsychiatric symptoms has been proposed for some years. A variety of studies have been undertaken to assess the nature and severity of these symptoms, which range from fatigue and depression to defects in attention and verbal reasoning. There is evidence of mild neurocognitive impairment in some patients with HCV infection, which is not fully attributable to liver dysfunction or psychosocial factors. Further evidence of a biological cerebral effect has arisen from studies using magnetic resonance spectroscopy; metabolic abnormalities correlate with cognitive dysfunction and resemble the patterns of neuroinflammation that have been described in HIV infection. Recent research has suggested that, in common with HIV infection, HCV may cross the blood brain barrier leading to neuroinflammation. Brain microvascular endothelial cells, astrocytes and microglia may be minor replication sites for HCV. Importantly, patient reported outcomes improve following successful antiviral therapy. Further research is required to elucidate the molecular basis for HCV entry and replication in the brain, and to clarify implications and recommendations for treatment.

HCV encephalopathy - an artefact due to medical care?

Anti-HCV positive individuals frequently complain about chronic disabling fatigue, mood alterations and deficits in concentration and memory. Several data provide evidence that such alterations are unrelated to hepatitis C virus (HCV) viremia. Thus, merely being exposed to HCV in the past may be sufficient to trigger, but the HCV exposure itself. This commentary reviews the available data upon this topic with special reference to the paper by Lowry and colleagues published in this issue of the Journal of Viral hepatitis. We will carefully discuss scientific reasons, why HCV may be directly involved in the development of neuropsychiatric symptoms independent from ongoing detectable viremia, as suggested by epidemiological data.

Peginterferon-α2b and ribavirin

Hepatitis C virus infection is among the leading causes of chronic liver disease in the USA and has a worldwide prevalence of approximately 300 million people. Chronic hepatitis C virus is the most common indication for liver transplantation in the USA. Due to the chronic nature of hepatitis C virus infection, these numbers are expected to grow fourfold in the next decade. Interferon-alpha(2b) monotherapy followed by combination therapy with ribavirin have been used to treat chronic hepatitis C virus with limited success. The development of pegylated interferon-alpha(2b), (Peg-intron, Schering-Plough) instituted the next chapter in hepatitis C virus therapy. The demonstration of its safety and efficacy led to a major trial studying coadministration with ribavirin for compensated chronic hepatitis C virus infection. Pegylated interferon combination therapy has improved efficacy over standard interferon combination therapy without an increase in adverse effects. This article reviews the data regarding pegylated interferon-alpha(2b) with ribavirin therapy. The pharmacokinetics and pharmacodynamics of combination therapy will be presented along with clinical trial data. The efficacy and ease of usage of Pegintron and ribavirin support its use for chronic hepatitis C virus infection.

Safety and efficacy of viramidine versus ribavirin in ViSER2: randomized, double-blind study in therapy-naive hepatitis C patients

BACKGROUND & AIMS

Pegylated interferon (peg-IFN) plus ribavirin (standard of care for chronic hepatitis C virus [HCV]), can cause dose-limiting anemia in up to 22% of patients. Viramidine is associated with a lower incidence of anemia because of its liver-targeting properties.

METHODS

The efficacy and safety of viramidine versus ribavirin plus peg-IFN alfa-2a was assessed in patients with HCV. Randomized patients received peg-IFN alfa-2a 180 mcg with viramidine 600 mg twice daily or weight-based doses of ribavirin 1000 or 1200 mg/day. Treatment duration was based on HCV ribonucleic acid (RNA) genotype: genotype 2/3 and non-2/3 patients were treated for 24 and 48 weeks, respectively. The primary efficacy end point was the non-inferiority of viramidine versus ribavirin (proportion of patients achieving sustained virologic response at week 24). The primary safety end point was the proportion of patients experiencing a hemoglobin event.

RESULTS

In total, 962 patients received peg-IFN alfa-2a with viramidine (n=644) or ribavirin (n=318). Sustained virologic response was achieved in 40% of viramidine-treated patients and 55% of ribavirin-treated patients (difference of proportions 0.150 [95% CI, 0.09, 0.21]). Improved efficacy was seen with higher viramidine exposure on a mg/kg basis. Viramidine was significantly superior to ribavirin in hemoglobin event rates (54% vs. 80%; p<0.001). Adverse event rates were similar between groups except for diarrhea (viramidine 29.5%; ribavirin 15.7%; p<0.0001).

CONCLUSIONS

Viramidine 600 mg BID did not meet the primary efficacy non-inferiority end point but met the safety end point. Determination of a viramidine dosage that would yield superior efficacy over ribavirin is needed.

Therapies for coronaviruses. Part 2: Inhibitors of intracellular life cycle

BACKGROUND

Severe acute respiratory syndrome (SARS) coronavirus emerged from an animal reservoir in 2002 and has the potential to reemerge, as shown by the occurrence of non-laboratory-associated new cases in the winter of 2003. In the absence of a vaccine, broad spectrum anticoronaviral medications are needed.

OBJECTIVE

Anticoronavirals targeting viral entry were reviewed in part I. Here we review anticoronaviral therapies directed against the intracellular life cycle, with an emphasis on allowed patents and pending patents.

METHOD

The published literature, in particular, patent publications is searched for relevant documents. The information is organized and critiqued.

RESULTS/CONCLUSION

Many promising anticoronaviral strategies are identified. Monoclonal antibodies, protease inhibitors, interferon-based drugs and nucleic-acid based antivirals are most advanced, each having its own advantages and disadvantages. A multi-pronged approach, keeping all venues open, is advocated.

Quality of life in hemodialysis patients: hepatitis C virus infection makes sense

PURPOSE

Hepatitis C virus (HCV) infection impairs quality of life (QOL) in patients who are not on dialysis therapy. In dialysis patients, how HCV infection affects QOL is unknown. In our study, we investigated the independent relationship between HCV infection and QOL.

METHODS

Sociodemographic and laboratory variables were recorded. Severity of depressive symptoms and QOL were assessed by Beck Depression Inventory (BDI) and Short Form-36 (SF-36), respectively.

RESULTS

Among 165 patients, 83 were anti-HCV antibody positive and 82 were anti-HCV antibody negative. Anti-HCV antibody positive patients had higher BDI scores than anti-HCV antibody negative patients (P = 0.011). Other than the social functioning subscale, all SF-36 subscales were lower in anti-HCV antibody positive patients when compared with anti-HCV negative patients. Anti-HCV antibody positive patients had lower physical (P = 0.003) and mental component summary scores (P = 0.018) than negative patients. Physical component summary score was independently associated with hemodialysis duration (P = 0.003), sleep disturbance (P = 0.046), BDI score (P = 0.027), albumin (P = 0.002), and serum hemoglobin (P < 0.0001). Physical component summary score was not associated with anti-HCV antibody positivity. Mental component summary score was independently associated with BDI score (P = 0.001), anti-HCV antibody positivity (P = 0.016), and serum hemoglobin (P < 0.0001).

CONCLUSION

HCV infection impairs QOL, especially in mental aspects, in hemodialysis patients.

Pegylated IFN-alpha2b plus ribavirin for treatment-naive patients coinfected with HCV and HIV

Since 1995, after the generalization of highly active antiretroviral therapy (HAART), HCV coinfection in patients with HIV has become a clinical problem of first magnitude. In fact, currently, HCV coinfection is the primary cause of morbi-mortality of AIDS patients in many hospitals. As a consequence, a significant number of clinical trials have been carried out during the past 8-10 years on HCV/HIV-coinfected patients, and have been coincident that the use of pegylated interferon (PEG-IFN) plus ribavirin should be now the gold standard for treating these patients. Various prospective, randomized studies have reached the conclusion that PEG-IFN-alpha(2b) plus ribavirin achieves HCV cure rates in approximately 50% of all patients, together with important clinical consequences, since hepatic illness progression stops or even reverts. Although adverse events are extremely common with this combined treatment, it is also true that their handling by experts means that only 10-15% of patients must abandon treatment.

Cognitive function, mood and health-related quality of life in hepatitis C virus (HCV)-monoinfected and HIV/HCV-coinfected individuals commencing HCV treatment

OBJECTIVES

The aim of the study was to examine cognitive function, mood and health-related quality of life (HRQOL), and their interrelationships, among hepatitis C virus (HCV)-monoinfected and HIV/HCV-coinfected individuals.

METHODS

Baseline neuropsychological and HRQOL measures of HCV-monoinfected and HIV/HCV-coinfected individuals commencing HCV treatment were examined from a prospective cohort study conducted between April 2003 and August 2005 in Sydney, Australia. Participants' neuropsychological performance and HRQOL were measured using computer-based battery, Trail Making Tests (TMT), Depression Anxiety Stress Scales (DASS), the Hepatitis Quality of Life Questionnaire (HQLQ), and the Visual Analogue Scale (VAS). Neuropsychological measures of HCV-infected patient groups were compared with those of two control groups consisting of HIV-monoinfected and uninfected individuals.

RESULTS

Similar cognitive function, mood and HRQOL were found in HCV-monoinfected (n=19) and HIV/HCV-coinfected (n=15) individuals. When compared with the HIV-monoinfected (n=30) and uninfected control (n=30) groups, subtle cognitive impairment in attention was found in the HIV/HCV-coinfected group (P<0.05). Twenty-one percent of the HCV-monoinfected group were classified as having cognitive impairment compared with 10% or less in the other groups. Sociodemographic characteristics, mood, HRQOL and HCV indices did not correlate with cognitive function.

CONCLUSIONS

Our findings indicate no statistically significant difference in neuropsychological and HRQOL impairments between HIV/HCV-coinfected individuals with nonadvanced HIV disease and HCV-monoinfected individuals. This lack of significant difference may relate to the relatively small study population.

Association of chronic hepatitis C with major depressive disorders: irrespective of interferon-alpha therapy

Background

Mood and anxiety symptoms in chronic hepatitis C (CHC) may be related to the patient awareness of the diagnosis and prognosis, to side effects induced by interferon (IFN)-alpha treatment, as well as to substance abuse. However, the observation of metabolic alterations in patients with CHC has led to hypothesize a direct effect of hepatitis C virus (HCV) on brain function. This study was aimed at elucidating whether CHC is associated with specific anxiety or mood disorders independently of confounding factors.

Methods

Patient cohort: consecutive patients, 135 with CHC and 76 with chronic hepatitis B (CHB). Exclusion criteria: previous treatment with IFN-alpha, co-infection with HCV and hepatitis B virus, infection with human immunodeficiency virus, drug or alcohol abuse, or malignancies. Controls: subjects without evidence of hepatitis randomly extracted from the database of a previous epidemiological study; they were divided into two groups of 540 (332 males) and 304 (220 males) as controls for patients with CHC and CHB, respectively. The psychiatric diagnosis was formulated by means of the Composite International Diagnostic Interview Simplified carried out by a physician according to DSM-IV criteria.

Results

A higher lifetime prevalence of major depressive disorder (MDD) was observed among CHC compared to CHB or controls. The risk of MDD was not statistically different between CHB and controls. Both the CHC and CHB groups showed a significantly higher frequency of panic disorder when compared to controls. No statistical differences were observed in the prevalence of general anxiety disorder and social phobia when CHC or CHB were compared to controls.

Conclusion

The present study provides the first evidence of an association between CHC and MDD, diagnosed on the basis of well-defined international criteria. This association is independent of treatment with IFN-alpha and is not influenced by substance or alcohol abuse. By contrast, anxiety disorders do not appear to be specifically associated with CHC.

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.

Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV)

Severe acute respiratory syndrome (SARS) is caused by a coronavirus (CoV), SARSCoV. SARS-CoV belongs to the family Coronaviridae, which are enveloped RNA viruses in the order Nidovirales. Global research efforts are continuing to increase the understanding of the virus, the pathogenesis of the disease it causes (SARS), and the “heterogeneity of individual infectiousness” as well as shedding light on how to prepare for other emerging viral diseases. Promising drugs and vaccines have been identified. The milestones achieved have resulted from a truly international effort. Molecular studies dissected the adaptation of this virus as it jumped from an intermediary animal, the civet, to humans, thus providing valuable insights into processes of molecular emergence.

Hépatite C et transplantation hépatique

Hepatitis C virus-related end-stage liver disease, alone or in combination with alcohol, has become the leading indication for liver transplantation in most transplant programs accounting for approximately half of transplants performed in European centers. Hepatitis C virus infection recurs virtually in every post-transplant patient. The natural history of hepatitis C after liver transplantation is variable. Progression of chronic hepatitis C virus is more aggressive after liver transplantation with a cumulative probability of developing graft cirrhosis estimated to reach 30% at 5 years. Approximately 10% of the patients with recurrent disease will die or require re-transplantation within 5 years post-transplantation. Several factors, including those related to the virus, the host, the environment and the donor, are probably implicated in the outcome. The immune status represents the main significant variable in influencing disease severity in hepatitis C virus-infected patients; with higher HCV viral load and the significant association described between the degree of immunosuppression and disease severity. Interventions to prevent, improve, or halt the recurrence of hepatitis C virus infection have been evaluated by multiple small studies worldwide with similar overall rates of virological clearance of approximately 9-30%. Current consensus recommends combination therapy with pegylated interferon and ribavirin for those patients with histological recurrence of hepatitis C virus infection and fibrosis. Therapy is adjusted to tolerance and rescued with granulocyte colony-stimulating factor and erythropoietin for bone marrow suppression. In this article we present a comprehensive review of post-transplant hepatitis C virus infection; in particular fibrosis progression and the major challenges according to treatment.

Cost-effectiveness of Chronic Hepatitis C Treatment with Thymosin Alpha-1

BACKGROUND

More than one million individuals in Mexico are infected with hepatitis C virus (HCV), and 80% are at risk for developing a chronic infection that could lead to hepatic cirrhosis and other complications that impact quality of life and institutional costs. The objective of the study was to determine the most cost-effective treatment against HCV among the following: peginterferon, peginterferon plus ribavirin, peginterferon plus ribavirin plus thymosin, and no treatment.

METHODS

We carried out cost-effectiveness analysis using the institutional perspective, including a 45-year time frame and a 3% discount rate for costs and effectiveness. We employed a Bayesian-focused decision tree and a Markov model. One- and two-way sensitivity analyses were performed, as well as threshold-oriented and probabilistic analyses, and we obtained acceptability curves and net health benefits.

RESULTS

Triple therapy (peginterferon plus ribavirin plus thymosin alpha-1) was dominant with lower cost and higher utility in relationship with peginterferon + ribavirin option, peginterferon alone and no-treatment option. In triple therapy the cost per unit of success was of 1,908 [USD/quality-adjusted life years (QALY)] compared with peginterferon plus ribavirin 2,277/QALY, peginterferon alone 2,929/QALY, and no treatment 4,204/QALY. Sensitivity analyses confirmed the robustness of the base case.

CONCLUSIONS

Peginterferon plus ribavirin plus thymosin alpha-1 option was dominant (lowest cost and highest effectiveness). Using no drug was the most expensive and least effective option.

Treatment of interferon-α for chronic hepatitis C

Combination therapy with polyethylene glycosylated IFN-alpha2a or IFN-alpha2b and ribavirin is currently the standard therapy for chronic hepatitis C. However, even with this therapy, hepatitis C virus cannot be eradicated in 50% of patients with refractory chronic hepatitis C. In addition, withdrawal or dose reduction occurs in approximately 40% of patients due to adverse effects. This treatment is also a contraindication in some patients, such as in patients with coexisting diseases or in elderly patients. For these patients, standard IFN-alpha monotherapy is even safer and more effective. In patients with chronic hepatitis C, IFN-alpha monotherapy results in a significant increase in the cumulative survival rate by suppressing the progression to hepatocellular carcinoma or liver failure. In addition, other efficacious therapeutic regimens have been employed, such as prolonged administration of standard IFN-alpha in elderly patients; prolonged low-dose continuous administration in patients with decompensated cirrhosis or hepatocellular carcinoma postoperative patients; and combination therapy with 5-fluorouracil and standard IFN-alpha for advanced hepatocellular carcinoma. Monotherapy with standard IFN-alpha should thus be recognised as one of the important therapeutic strategies for chronic hepatitis C.

Results of a Study of Prolonging Treatment with Pegylated Interferon-α2A plus Ribavirin in HIV/HCV-Coinfected Patients with No Early Virological Response

Objective

To assess the efficacy and safety of an extended treatment period in HIV/hepatitis C virus (HCV)-coinfected patients without early virological response (EVR).

Methods

Patients received pegylated interferon (peg-INF)-α2a 180 μg/week plus ribavirin 800 mg/d for 12 weeks. Patients achieving EVR at week 12 continued under therapy for an additional 12 or 36 weeks depending on genotype. Patients without EVR were randomized to complete the standard treatment or treatment lasting 72 weeks (extension arm).

Results

One hundred and ten patients were included (mean age 38.7 years, mean weight 68 kg, 74% males, 74% on highly active antiretroviral therapy, mean CD4+ T-cell count 564 cells/mm3). Fifty-one patients harboured genotype 1, 44 genotype 2/3, and 15 genotype 4. Fifty-three had an HCV load >800,000 IU/ml. Premature interruptions occurred in 32.7%. EVR was achieved in 63.6% (51% in genotype 1, 88.6% in genotype 2/3, 33.3% in genotype 4). End-of-treatment response was 52.7% (47.2% in genotype 1, 68.2% in genotype 2/3, 26.7% in genotype 4). Sustained virological response (SVR) was achieved in 41.8% (37.3% in genotype 1, 54.6% in genotype 2/3, 20% in genotype 4). Only one patient allocated to the extended arm achieved SVR. The rate of drop-outs in the extension arm was 68%. The negative predictive value of EVR was 97.5%.

Conclusions

This study shows no benefit of extending therapy in patients without EVR at week 12. Measures to improve adherence to HCV antiviral therapy should be considered when new approaches based on extended periods of treatment are investigated.

Central nervous system changes in hepatitis C virus infection

Patients with chronic hepatitis C virus (HCV) infection frequently describe neuropsychological symptoms. Although hepatic encephalopathy is the best established neurological association of HCV infection, there is a growing body of literature on cerebral dysfunction, occurring at an early stage of chronic HCV infection, well before the development of cirrhosis. In this review we describe recent studies that have documented mild, but significant neurocognitive impairment in HCV infection. These deficits in patients with minimal or absent liver disease do not appear to be attributable to a history of substance abuse, coexistent depression or hepatic encephalopathy. Recent studies employing in-vivo magnetic resonance spectroscopy have suggested that a biological mechanism associated with the virus may be responsible. The hypothesis that HCV infection of the central nervous system may be related to the reported neuropsychological symptoms and cognitive impairment is supported by molecular virological studies of post-mortem brain tissue.

The effect of hepatitis C virus infection on health-related quality of life in prisoners

Hepatitis C virus (HCV) infection in prisoners represents an important public health problem. However, there is very little information about HCV-related health-related quality of life (HRQOL). We examined the effect of HCV antibody positivity, HCV viremia, and being a prisoner on prisoners'' HRQOL. Population-based health surveys incorporating HCV screening were conducted among prisoners at New South Wales (NSW), Australia, correctional centers in 1996 and 2001. HCV antibody and HCV RNA status were determined from venous blood sampling. HRQOL and mood status were assessed using the Short Form-36 (SF-36) Health Survey and Beck Depression Inventory (BDI). Comparison of HRQOL scores between HCV antibody negative, HCV antibody positive/non-viremic, and HCV antibody positive/viremic and assessment of temporal change in HRQOL between 1996 and 2001 within groups were made using ANCOVA adjusting for confounders. Factors associated with HRQOL were determined in linear regression models. Analyses between HCV antibody negative (n = 423), HCV positive/non-viremic (n = 89), and HCV positive/viremic (n = 178) prisoners found no measurable effect of HCV on HRQOL, including that attributable to HCV viremia. Compared to uninfected Australian population norms, prisoners had lower HRQOL irrespective of HCV status. The prevalence of 'moderate' to 'severe' depressive symptoms was greater in the HCV antibody positive/viremic group than the HCV antibody positive/non-viremic group or the HCV antibody negative group. Selected demographic factors (age), co-morbidity, severity of depressive symptoms and medical care utilization influenced HRQOL. There was evidence to support the effect of knowledge of HCV status on HRQOL. In conclusion, our findings contrast with previous studies in non-prisoner groups in which HCV infection appears to decrease overall HRQOL. Non-HCV factors may override HCV-specific HRQOL impairment in this population. Targeted management strategies are required to improve HRQOL of prisoners.

The neuropsychological and neurological impact of hepatitis C virus co-infection in HIV-infected subjects

OBJECTIVE

To evaluate the effect of hepatitis C virus (HCV)/HIV co-infection on neuropsychological performance and neurological status in HIV/HCV treatment-naive HIV-1-infected individuals we conducted a cross-sectional study using baseline data from an HIV therapy trial.

METHODS

HCV status was determined by the presence of anti-HCV antibodies. Neuropsychological function was evaluated by Trailmaking tests, and the Digit Symbol Task. Depression was assessed using the Center for Epidemiologic Studies--Depression Scale. Sleep quality was evaluated by the Pittsburgh Sleep Quality Index and anxiety by the State-Trait Anxiety Inventory for Adults. A questionnaire was designed grading the severity of a variety of symptoms.

RESULTS

Of 264 patients with HCV status data, 30 were HCV positive and 234 were HCV negative. Both groups were comparable except that HCV-positive individuals had a higher prevalence of intravenous drug use and lower educational level. The HCV-positive group had a significantly lower neuropsychological performance overall. Multivariate modeling supported an association between HCV infection status with test performance in the Digit Symbol Task and mood parameters even when controlling for potentially confounding variables. Marginal differences were noted with respect to symptom questionnaire scores and global sleep. No differences were noted with respect to anxiety.

CONCLUSION

The findings suggest that HCV/HIV co-infection has an adverse impact on neuropsychological function. HCV may also be associated with depressed mood, particularly somatic depressive symptoms. Although confounding contributors to neuropsychological performance are difficult to exclude, exploratory modeling supports the association between HCV infection status and some impairment of neuropsychological performance and depressed mood.

A review of cognitive impairment and cerebral metabolite abnormalities in patients with hepatitis C infection

Numerous studies have reported associations between chronic hepatitis C virus (HCV) infection and fatigue, depression and impairments in health-related quality of life, which are independent of the severity of liver disease. Although there are a large number of potential explanations for these symptoms, including a history of substance abuse and associated personality types, or the effect of the diagnosis of HCV infection itself, there has been recent interest in the possibility of a biological effect of HCV infection on cerebral function. There is emerging evidence of mild, but significant neurocognitive impairment in HCV infection, which cannot be wholly attributed to substance abuse, co-existent depression or hepatic encephalopathy. Impairments are predominantly in the domains of attention, concentration and information processing speed. Furthermore, in-vivo cerebral magnetic resonance spectroscopy studies in patients with hepatitis C and normal liver function have reported elevations in cerebral choline-containing compounds and reductions in N-acetyl aspartate, suggesting that a biological mechanism may underlie the cognitive findings. The recent detection of HCV genetic sequences in post-mortem brain tissue raises the intriguing possibility that HCV infection of the central nervous system may be related to the reported neuropsychological symptoms and cognitive impairment.

Involvement of PKR and RNase L in translational control and induction of apoptosis after Hepatitis C polyprotein expression from a vaccinia virus recombinant

Background

Hepatitis C virus (HCV) infection is of growing concern in public health with around 350 million chronically infected individuals worldwide. Although the IFN-α/rivabirin is the only approved therapy with 10–30% clinical efficacy, the protective molecular mechanism involved during the treatment is still unknown. To analyze the effect of HCV polyprotein expression on the antiviral response of the host, we developed a novel vaccinia virus (VV)-based delivery system (VT7-HCV7.9) where structural and nonstructural (except part of NS5B) proteins of HCV ORF from genotype 1b are efficiently expressed and produced, and timely regulated in mammalian cell lines.

Results

Regulated transcript production and viral polypeptide processing was demonstrated in various cell lines infected with the recombinant VT7-HCV7.9, indicating that the cellular and viral proteolytic machineries are functional within these cells. The inducible expression of the HCV polyprotein by VV inhibits the synthesis of both host and viral proteins over the time and also induces apoptosis in HeLa and HepG2-infected cells. These effects occur accompanying with the phosphorylation of the translation initiation factor eIF-2α. In cells co-infected with VT7-HCV7.9 and a recombinant VV expressing the dominant negative eIF-2α-S51A mutant in the presence of the inductor isopropyl-thiogalactoside (IPTG), protein synthesis is rescued. The IFN-inducible protein kinase PKR is responsible for the translational block, as demonstrated with PKR-/- and PKR+/+ cell lines. However, apoptosis induced by VT7-HCV7.9 is mediated by the RNase L pathway, in a PKR-independent manner.

Conclusion

These findings demonstrate the antiviral relevance of the proteins induced by interferon, PKR and RNase L during expression from a VV recombinant of the HCV polyprotein in human cell lines. HCV polyprotein expression caused a severe cytopathological effect in human cells as a result of inhibition of protein synthesis and apoptosis induction, triggered by the activation of the IFN-induced enzymes PKR and RNase L systems. Thus, the virus-cell system described here highlights the relevance of the IFN system as a protective mechanism against HCV infection.

A Randomized, Double-Blind, Placebo-Controlled Dose-Escalation Trial of Merimepodib (VX-497) and Interferon-α in Previously Untreated Patients with Chronic Hepatitis C

Inhibition of inosine monophosphate dehydrogenase (IMPDH) is one of several proposed mechanisms of action for ribavirin (RBV), a critical component of the current treatment for chronic hepatitis C (CHC).

This study was a double-blind, placebo-controlled dose-escalation study of a novel, selective, orally active small molecule inhibitor of IMPDH, merimepodib (VX-497 or MMPD) in combination with standard interferon-alpha (IFN-α). Fifty-four treatment-naive patients with genotype-1 CHC were randomized to receive IFN-α 3 MIU subcutaneously three times a week, alone or in combination with 100 mg or 300 mg (every 8 h) of MMPD for 4 weeks. At the end of 4 weeks, all patients were offered 48 weeks of treatment with IFN-α/RBV. The objectives of the study were to evaluate the tolerability of the IFN-α/MMPD combination and to evaluate whether MMPD had an on-treatment effect on HCV-RNA, similar to RBV when added to IFN-α.

The drug combination was generally well tolerated; one patient at the higher dose discontinued because of elevated alanine aminotransferase levels. No pharmacokinetic interactions were evident between the two drugs. Analysis of covariance that adjusted for a baseline imbalance in HCV-RNA in the intent-to-treat population did not show any significant differences between the treatment groups, or between MMPD plus IFN-α compared with IFN-α alone. However, the per-protocol primary efficacy analysis based on treatment-compliant patients demonstrated a greater reduction in mean HCV-RNA in the combination of 100 mg MMPD plus IFN-α compared with IFN-α alone (-1.78 log vs -0.86 log, P=0.037).

In conclusion, the addition of a selective IMPDH inhibitor to IFN-α was well tolerated. In a low-dose range, the addition of MMPD may have the potential to add to the antiviral efficacy of IFN-α. Larger, longer duration trials incorporating pegylated IFN would be required to determine whether this combination, alone or with RBV, would increase either early or sustained virological response rates.

Hepatitis C virus core protein suppresses NF-kappaB activation and cyclooxygenase-2 expression by direct interaction with IkappaB kinase beta

In addition to hepatocytes, hepatitis C virus (HCV) infects immune cells, including macrophages. However, little is known concerning the impact of HCV infection on cellular functions of these immune effector cells. Lipopolysaccharide (LPS) activates IkappaB kinase (IKK) signalsome and NF-kappaB, which leads to the expression of cyclooxygenase-2 (COX-2), which catalyzes production of prostaglandins, potent effectors on inflammation and possibly hepatitis. Here, we examined whether expression of HCV core interferes with IKK signalsome activity and COX-2 expression in activated macrophages. In reporter assays, HCV core inhibited NF-kappaB activation in RAW 264.7 and MH-S murine macrophage cell lines treated with bacterial LPS. HCV core inhibited IKK signalsome and IKKbeta kinase activities induced by tumor necrosis factor alpha in HeLa cells and coexpressed IKKgamma in 293 cells, respectively. HCV core was coprecipitated with IKappaKappabeta and prevented nuclear translocation of IKKbeta. NF-kappaB activation by either LPS or overexpression of IKKbeta was sufficient to induce robust expression of COX-2, which was markedly suppressed by ectopic expression of HCV core. Together, these data indicate that HCV core suppresses IKK signalsome activity, which blunts COX-2 expression in macrophages. Additional studies are necessary to determine whether interrupted COX-2 expression by HCV core contributes to HCV pathogenesis.

Combination of a hepatitis C virus NS3-NS4A protease inhibitor and alpha interferon synergistically inhibits viral RNA replication and facilitates viral RNA clearance in replicon cells

The present standard of care for hepatitis C virus (HCV) infection is pegylated alpha interferon (IFN-alpha) in combination with ribavirin. However, specific antivirals such as HCV NS3-NS4A protease inhibitors are now in clinical development, and these agents can potentially be used in combination with the present treatments. Therefore, it is important to investigate the potential benefits or adverse effects of these new combinations by using available in vitro HCV culture systems first. In the present study we demonstrate that the combination of a specific HCV NS3-NS4A protease inhibitor and IFN-alpha synergistically inhibits HCV RNA replication in replicon cells, with little or no increase in cytotoxicity. Furthermore, the benefit of the combination was sustained over time, such that a greater than 3-log reduction in HCV RNA levels was achieved following 9 days of treatment. The viral RNA appeared to be cleared from the replicon cells after 14 days of treatment, and no viral RNA rebound was observed upon withdrawal of the inhibitors. In each case, the antiviral effects obtained with higher concentrations of either the protease inhibitor alone or IFN-alpha alone can be achieved by a combination of both agents at lower concentrations, which may potentially reduce the risk of possible adverse effects associated with high doses of either agent.

Hepatitis C virus infection affects the brain-evidence from psychometric studies and magnetic resonance spectroscopy

BACKGROUND/AIMS

Up to 50% of patients infected with the hepatitis C virus (HCV) complain of chronic fatigue and difficulties in concentration and memory. The aim of the present study was to seek evidence for the presence of central nervous system involvement in HCV infected patients with only mild liver disease.

METHODS

Thirty HCV infected patients with normal liver function, 15 of whom were identified as having mild and 15 moderate to severe fatigue using the fatigue impact scale, underwent neurological and neuropsychological examination, electroencephalography (EEG) and cerebral proton magnetic resonance imaging (MRI) and spectroscopy (MRS). Fifteen healthy volunteers, matched for age and educational attainment, served as controls.

RESULTS

In comparison to the healthy controls the patients with HCV infection showed evidence of cognitive impairment, primarily attention and higher executive functions, higher levels of anxiety and depression and impairment of quality of life. In addition they showed a significant decrease of the N-acetyl-aspartate/creatine ratio in the cerebral cortex on 1H MRS while the EEG was slowed in 25%. In general the deficits were more marked in the patients with moderate rather than mild fatigue.

CONCLUSIONS

The data provide evidence of central nervous system involvement in patients with HCV infection.

Epidemiology, Diagnosis, and Treatment of Chronic Hepatitis C

The hepatitis C virus (HCV) is a leading cause of chronic liver disease, cirrhosis, and hepatocellular carcinoma and is also a common indication for liver transplantation. Interferon alfa monotherapy leads to a sustained virologic response in only 10% to 15% of HCV-infected patients. The sustained virologic response rates can be increased to approximately 40% with interferon alfa-2b and ribavirin combination therapy for up to 48 weeks. However, recent clinical trials demonstrated that pegylated interferon in combination with ribavirin can improve the response rates even further, with more than 50% of patients having a sustained virologic response to treatment. Although new therapies are emerging, significant progress must be made to reduce the morbidity and mortality from HCV infection.

Identification of unique hepatitis C virus quasispecies in the central nervous system and comparative analysis of internal translational efficiency of brain, liver, and serum variants

Reports of cerebral dysfunction in chronic hepatitis C virus (HCV) infection have led to the suggestion that HCV may infect the central nervous system (CNS). We used reverse transcription-PCR, cloning, and sequencing to define quasispecies for the HCV internal ribosomal entry site (IRES) and hypervariable region 1 (HVR1) in autopsy-derived brain, liver, lymph node, and serum samples. There was evidence of tissue compartmentalization of sequences in the brain in two patients, with between 24 and 55% of brain-derived IRES sequences absent from the serum, and significant phylogenetic and phenetic clustering of the brain and lymph node HVR1 sequences. The IRES initiates cap-independent translation of the viral polyprotein. Two unique brain-derived IRES mutations (C(204)-->A and G(243)-->A), which have previously been associated with lymphoid replication and altered translational efficiency in cell culture, were found in one patient. We used a dicistronic reporter vector to test whether brain-derived variants showed altered IRES-mediated translational efficiency, which might favor CNS infection. The translational efficiencies of the brain-derived IRES sequences were generally reduced compared to those of the master serum and liver sequences in rabbit reticulocyte cell lysates and two human cell lines, HuH7 (liver) and CHME3 (microglial). The C(204)-->A and G(243)-->A mutations showed preserved translational efficiency in HuH7 cells but reduced efficiency in CHME3 cells. Our data provide evidence that the CNS is a site of HCV replication, consistent with the recent demonstration of negative-strand HCV RNA in brain, and suggest that IRES polymorphisms may be important as a viral strategy of reduced translation to favor latency in the CNS.

Influence of HFE gene polymorphism on the progression and treatment of chronic hepatitis C

We analysed liver histology findings in a large cohort of patients with chronic hepatitis C and in roughly half of them their response to interferon-alpha-based on iron parameters and HFE status. Histological activity and virological response to antiviral therapy (n = 146) were analysed in 273 immunocompetent and nonalcoholic patients with chronic hepatitis C, in terms of serum iron load, intrahepatic iron load (n = 110) and HFE mutations. Patients who were heterozygous for the C282Y and H63D mutations exhibited higher iron serum parameters than subjects without these mutations. The intrahepatic iron load was higher in H63D patients only. No association was observed between HFE mutations and histological activity. Increased iron parameters were associated with liver disease severity by univariate analysis only. Genotype 1 and ferritinaemia were associated with a poor response to antiviral therapy, whereas the H63D mutation emerged as a positive predictive factor for end of treatment and sustained antiviral response. Therefore, in chronic hepatitis C patients serum and intrahepatic iron levels were weakly correlated with histological activity, while HFE mutations were not. As for the response to interferon-alpha, elevated ferritinaemia constituted a negative predictive factor whereas the H63D mutation was a positive one. The H63D mutation might form part of an immunogenetic profile influencing the response to interferon therapy.

[Role of interferons in the treatment of hepatitis B and hepatitis C virus infections]

BACKGROUND

Since the discovery of hepatitis C (HCV), the efficacy of treatment has significantly progressed using standard mono-therapy: with Interferon alpha (IFN) during six months we obtained approximately 10% sustained response and currently with the association of pegylated IFN and Ribavirin a 55% sustained response was achieved.

CURRENT POSITION AND MAJOR POINTS

HCV infection continues to present therapeutic problems which have not entirely been solved, mainly related to clinical and biological tolerance, and non-responders. Moreover, the care of patients with extra-hepatic localization, cirrhotic patients, as well as therapeutic problems of co-infected HIV-HCV patients. As regards hepatitis B (HBV) new effective treatments against this virus have appeared, IFN then nucleoside analogs, some of which are available in France (i.e. lamivudine, adefovir, dipovoxil). The main objective of chronic hepatitis B treatment is to obtain the complete inhibition of the HBV virus by Hbe-antigen antibody seroconversion which would therefore significantly increase patient survival. In this article the advantages and disadvantages of the different treatments are assessed.

FUTURE PERSPECTIVES

Despite the considerable and rapid progress obtained in the therapeutic treatment of infection due to HCV and HBV a number of unknown factors remain, which warrants further trials, in particular to evaluate the efficacy as well as the tolerance of the antiviral agent association.

To interfere and to anti-interfere: the interplay between hepatitis C virus and interferon

As popular strategies used by numerous viruses, interception of interferon (IFN) signaling and inhibition of IFN-induced antiviral functions allow viruses to evade the host immune response and set up successful infections. Hepatitis C virus (HCV), the leading cause of chronic liver disease worldwide and a major public health hazard, causes persistent infection in the majority of infected individuals. IFN-based therapies, currently the only ones available for HCV infection, have been unable to eliminate viral infection in the majority of patients, and many studies suggest that HCV possesses mechanisms to antagonize the IFN-induced antiviral response. Multiple viral, host, and IFN-associated factors have been implicated in the interplay between HCV and IFN. Two viral proteins, NS5A and E2, became the focus of much attention and extensive study because of their abilities to inhibit IFN-induced, double-stranded RNA-activated protein kinase (PKR), a major mediator of the IFN-induced biologic response, and to perturb the IFN signaling pathway. In this review, we discuss the significance of the interferon sensitivity determining region (ISDR) within NS5A, which has been the subject of intense debates. In addition, we discuss the potential mechanisms by which NS5A interferes with IFN signaling and the current working models. Further understanding of the molecular mechanisms underlying the interaction between HCV and IFN will likely facilitate improvement of current IFN-based therapies and development of novel treatments for the HCV pandemic. Future HCV research will benefit from both the development of efficient, convenient model systems for viral propagation, and the utilization of high throughput, genomic-scale approaches.

Peginterferon alfa-2a plus ribavirin for chronic hepatitis C virus infection

BACKGROUND

Treatment with peginterferon alfa-2a alone produces significantly higher sustained virologic responses than treatment with interferon alfa-2a alone in patients with chronic hepatitis C virus (HCV) infection. We compared the efficacy and safety of peginterferon alfa-2a plus ribavirin, interferon alfa-2b plus ribavirin, and peginterferon alfa-2a alone in the initial treatment of chronic hepatitis C.

METHODS

A total of 1121 patients were randomly assigned to treatment and received at least one dose of study medication, consisting of 180 microg of peginterferon alfa-2a once weekly plus daily ribavirin (1000 or 1200 mg, depending on body weight), weekly peginterferon alfa-2a plus daily placebo, or 3 million units of interferon alfa-2b thrice weekly plus daily ribavirin for 48 weeks.

RESULTS

A significantly higher proportion of patients who received peginterferon alfa-2a plus ribavirin had a sustained virologic response (defined as the absence of detectable HCV RNA 24 weeks after cessation of therapy) than of patients who received interferon alfa-2b plus ribavirin (56 percent vs. 44 percent, P<0.001) or peginterferon alfa-2a alone (56 percent vs. 29 percent, P<0.001). The proportions of patients with HCV genotype 1 who had sustained virologic responses were 46 percent, 36 percent, and 21 percent, respectively, for the three regimens. Among patients with HCV genotype 1 and high base-line levels of HCV RNA, the proportions of those with sustained virologic responses were 41 percent, 33 percent, and 13 percent, respectively. The overall safety profiles of the three treatment regimens were similar; the incidence of influenza-like symptoms and depression was lower in the groups receiving peginterferon alfa-2a than in the group receiving interferon alfa-2b plus ribavirin.

CONCLUSIONS

In patients with chronic hepatitis C, once-weekly peginterferon alfa-2a plus ribavirin was tolerated as well as interferon alfa-2b plus ribavirin and produced significant improvements in the rate of sustained virologic response, as compared with interferon alfa-2b plus ribavirin or peginterferon alfa-2a alone.

Hepatitis C virus replication is directly inhibited by IFN-alpha in a full-length binary expression system

Hepatitis C virus (HCV) is a leading cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma. The absence of culture systems permissive for HCV replication has presented a major bottleneck to antiviral development. We sought to recapitulate the early steps in the life cycle of HCV by means of DNA-based expression of viral genomic sequences. Here we report expression of replicating HCV RNA by using a, to our knowledge, novel binary expression system in which cells were transfected with a T7 polymerase-driven full-length HCV cDNA plasmid containing a cis-acting hepatitis Delta ribozyme to control 3' cleavage, and infected with vaccinia-T7 polymerase. HCV genomic and replicative strand synthesis, in addition to protein synthesis, was detectable and depended on full-length HCV sequences. Moreover, the system was capable of generating HCV RNA quasispecies, consistent with the action of the low-fidelity HCV NS5B RNA polymerase. IFN-alpha, but not ribavirin, directly inhibited the viral replicative cycle in these cells, identifying the virus itself and not solely the immune system as a direct target of IFN action. The availability of a cell-based test for viral replication will facilitate screening of inhibitory compounds, analysis of IFN-resistance mechanisms, and analysis of virus-host cell interactions.

Assessment, by transcription-mediated amplification, of virologic response in patients with chronic hepatitis C virus treated with peginterferon alpha-2a

Transcription-mediated amplification (TMA) is an isothermal, autocatalytic target amplification method which has the potential to detect less than 50 hepatitis C virus (HCV) RNA copies/ml (10 IU/ml). The TMA assay was used to assess the presence of residual HCV RNA in plasma from patients treated with polyethylene glycol-modified interferon alpha-2a (peginterferon alpha-2a) who showed a virologic relapse after the end of therapy. Stored end-of-treatment and end-of-follow-up plasma samples from 177 of 267 patients treated with peginterferon alpha-2a (S. Zeuzem et al., N. Engl. J. Med. 343:1666--1672, 2000) were available for retesting by TMA. Plasma samples from patients in the same study who exhibited virologic relapse after treatment with standard interferon alpha-2a served as controls. Virologic response during the trial was defined as HCV RNA that was undetectable using a PCR-based test system with a sensitivity of 50 IU/mL (Cobas Amplicor HCV version 2.0) and was compared with TMA-based retesting results (VERSANT HCV RNA Qualitative Assay). Residual HCV RNA was detected in 4 of 60 cases (7%) by the TMA technology in end-of-treatment plasma samples from patients who relapsed after receiving peginterferon alpha-2a and in 6 of 18 patients (33%) following therapy with standard interferon alpha-2a. For peginterferon alpha-2a-treated patients with sustained virologic response, HCV RNA was detectable by TMA in end-of-treatment samples in 3 of 78 cases but in none of the end-of-follow-up samples. For all end-of-treatment and end-of-follow-up plasma samples of virologic nonresponders, a complete concordance between the PCR-based assay and TMA was observed. In conclusion, in patients with virologic relapse after the end of therapy, according to PCR, who were treated with peginterferon alpha-2a or standard interferon alpha-2a, residual HCV RNA was detectable in end-of-treatment samples by the TMA-based assay in 7 or 33% of cases, respectively. The lower rate of residual HCV RNA detection by TMA for patients treated with peginterferon alpha-2a than that for patients treated with standard interferon alpha-2a may be due to the maintained antiviral pressure of the long-acting peginterferon alpha-2a at the end-of-treatment visit.

[Why are not all patients with chronic liver disease associated with hepatitis C virus treated?]

AIMS

To analyze the prevalence of patients with chronic liver disease associated with hepatitis C virus (HCV) not undergoing antiviral treatment and the reasons for which this treatment was not indicated.

PATIENTS AND METHODS

718 patients with HCV infection referred for therapeutic evaluation between January 1990 and January 1998. Demographic, clinical, biological and histological variables were prospectively analyzed. The patients were divided into two groups: treated and untreated.

RESULTS

393 patients were treated and in 325 patients antiviral treatment was not considered to be indicated. The most frequent reasons for not starting therapy were advanced age, the presence of decompensated cirrhosis and the patients' refusal to undergo antiviral treatment.

CONCLUSIONS

A broad subgroup of patients with chronic liver disease associated with HCV do not receive antiviral treatment. This is related with: a) patients' advanced age at diagnosis, b) diagnosis at the advanced stages of the disease, and c) patients' refusal to undergo such treatment after being informed of its potential risks and benefits.

Therapy for chronic hepatitis C

BACKGROUND/AIMS

in Hungary, over the past 5 years more than 900 patients with chronic hepatitis C have been examined for treatment with interferon at 16 major hepatology centres, using unified diagnostic and therapeutical criteria. Authors give an account of their experiences on the clinical features of patients with chronic hepatitis C and report the results of the interferon therapy.

METHODS

a total of 993 patients--virtually the entire Hungarian hepatitis C patient population who had been referred for interferon treatment--were included in the program. Actually, the sustained efficacy of the therapy was evaluated in 724 cases. Treatment protocols (dose of interferon and duration of therapy) have changed with time from a weekly dose of 3x3 MU IFN for 6 months in the first period, to 3x3-5 MU for 12 months in the second period, and finally in the third period a combination therapy with ribavirin has also been introduced.

RESULTS

in the first period, the end-of-treatment response (ETR) was 35%, sustained response (SR) 13%, the second phase schedule resulted in 42% ETR and 22% SR, while in the third period, ETR was 49% and SR 36%, respectively. Fibrosis in histology and baseline pretreatment HCV-RNA level appeared as predictors of response. The duration of treatment and the total dose of interferon exerted a moderate effect on therapeutic efficacy. Neither age nor gender influenced the outcome.

CONCLUSIONS

our results-obtained in a Central East European country-are in accordance with findings of suboptimal efficacy of traditional interferon monotherapy for chronic hepatitis C reported in the West, and suggest the benefit of the combination treatment of interferon with ribavirin.

Detection of residual hepatitis C virus RNA by transcription-mediated amplification in patients with complete virologic response according to polymerase chain reaction-based assays

A considerable proportion of patients with chronic hepatitis C who achieve a virologic end-of-treatment response relapse after discontinuation of therapy. It is conceivable that polymerase chain reaction (PCR)-based assays with a lower detection limit of 100 to 1, 000 hepatitic C virus (HCV) RNA copies/mL are still too insensitive to detect residual viremia. End-of-treatment serum samples of 47 patients with a virologic relapse according to results of qualitative PCR assays (Amplicor HCV; Roche Molecular Systems, Mannheim, Germany) were tested by transcription-mediated amplification (TMA), an isothermal, autocatalytic target amplification method that has the potential to detect less than 50 HCV RNA copies/mL. Virologic sustained responders (n = 59) and nonresponders (n = 49) served as controls. In end-of-treatment serum samples of virologic sustained responders and nonresponders an almost complete concordance between PCR and TMA results was observed (98%). However, HCV RNA was detectable by TMA in end-of-treatment serum samples from 16 of 25 relapse patients (64%) who were HCV-RNA-negative according to Amplicor HCV version 1.0 (lower detection limit 1,000 copies/mL) and in 8 of 22 patients (36%) who were HCV-RNA-negative according to Amplicor HCV version 2.0 (lower detection limit 100 copies/mL). End-of-treatment alanine transaminase (ALT) levels of sustained virologic responders and TMA-negative relapsers were similar, whereas a trend toward higher ALT values was observed in TMA-positive relapsers compared with sustained virologic responders (P = 0.09). In conclusion, HCV RNA can be detected at the end of treatment by TMA in a considerable proportion of patients who were classified as virologic end-of-treatment responders with a subsequent virologic relapse according to PCR-based methods.

Pathogenesis, diagnosis and management of hepatitis C

The hepatitis C virus (HCV) is the leading cause of chronic liver disease worldwide. It is estimated that about 170 million people are chronically infected with HCV. Chronic hepatitis C is a major cause of cirrhosis and hepatocellular carcinoma and HCV-related end-stage liver disease is, in many countries, the first cause of liver transplantation. HCV infection is characterized by its propensity to chronicity. Because of its high genetic variability, HCV has the capability to escape the immune response of the host. HCV is not directly cytopathic and liver lesions are mainly related to immune-mediated mechanisms, which are characterized by a predominant type 1 helper cell response. Co-factors influencing the outcome of the disease including age, gender and alcohol consumption are poorly understood and other factors such as immunologic and genetic factors may play an important role. Recent studies have shown that the combination therapy with alpha interferon and ribavirin induces a sustained virological response in about 40% of patients with chronic hepatitis C. The sustained response rates are mainly dependent on the viral genotype (roughly 60% in genotype non-1 and 30% in genotype 1). Reliable diagnostic tools are now available and useful for detecting HCV infection, to quantify viral load and to determine the viral type. The assessment of the viral quasispecies and the characterization of viral sequences might be clinically relevant but standardized and simple techniques are needed. The lack of animal models and of in vitro culture systems hampers the understanding of the pathogenesis of chronic hepatitis C and the development of new antivirals. New therapeutic schedules with higher and/or daily doses of alpha interferon do not seem to improve the efficacy greatly. The conjugation with polyethylene glycol (PEG) improved the pharmacodynamics and the efficacy of alpha interferon. Emerging new therapies include inhibitors of viral enzymes (protease, helicase and polymerase), cytokines (IL-12 and IL-10), antisense oligonucleotides and ribozymes. The first candidate compounds should be available in the next few years. The development of an effective vaccine remains the most difficult and pressing challenge. Because of the high protein variability of HCV, protective vaccines could be extremely difficult to produce and therapeutic vaccines seem more realistic. Considerable progress has been made in the field of HCV since its discovery 10 years ago but a major effort needs to be made in the next decade to control HCV-related liver disease.

[Effects of surgical treatment on hypertrophy of the myocardium of the left ventricle in patients with symptomatic arterial hypertension]

A total of 50 patients with arterial hypertension were examined. Group 1 included 28 patients with renovascular hypertension, 18 of them had unilateral renal artery stenosis, the remaining 10 had bilateral renal artery stenosis. Group 2 consisted of 16 patients with primary aldosteronism. Group 3 comprised 6 patients with pheochromocytoma. The examination was made with echocardiograph. Changes in left ventricular myocardial mass (LVMM) were studied 1 and 6 months after surgical intervention. The maximum hypertrophy was observed in the patients with primary aldosteronism, no changes occurred in any of the groups examined 1 month after surgical management. The LVMM was found to be significantly diminished by 13% in the patients with renovascular hypertension and by 23% in patients with adrenal tumors (pheochromocytoma, aldosteroma).