Asian-Pacific consensus statement on the management of chronic hepatitis B: a 2005 update

Liver injury is associated with enhanced regulatory T-cell activity in patients with chronic hepatitis B

Chronic hepatitis B virus (HBV) infection is associated with impairment of HBV-specific immune responses. Recently, it has been shown that regulatory T (Treg) cells downregulate HBV-specific immune responses but their role in chronic hepatitis B is still controversial. We hypothesized that liver injury enhances the influence of Treg cells on HBV-specific immune responses. The frequency of Treg cell and the in vitro expansion of HBV-specific CD8+ T cell detected by the tetramer method were investigated in 79 patients with chronic hepatitis B. Thirty-three healthy volunteers were enrolled to measure the frequency of Treg cell as controls. The results showed that in chronic hepatitis B cases, the frequency of Treg cells in peripheral blood was significantly higher than that in normal volunteers. The higher level of serum transaminase was associated with higher frequency of Treg cells, which both had a linear correlation relationship. HBV-DNA level, HBe status, age and sex had no statistical association with Treg cell frequency. Furthermore, in patients with higher serum transaminase levels, the expansion of HBV-specific CD8+ T cells was higher after removal of Treg cells when compared with patients with lower serum transaminase levels. In conclusion, our data indicate a significant association between serum transaminase level and frequency/activity of Treg cells. Based on this observation, we propose that liver-injury enhances Treg cell frequency/activity in chronic hepatitis B patients.

Appropriate use of interferon for treatment of chronic hepatitis B

Hepatitis B is not only a preventable but now treatable disease. Five drugs have been approved for the treatment of chronic hepatitis B virus (HBV) infection: standard interferon-alpha (IFN), pegylated IFN, lamivudine, adefovir dipivoxil and entecavir. Among these agents, the responses to interferon therapy are invariably influenced by both host and viral factors. Therefore, understanding these factors is important for practicing hepatologists, and it may help design individualized medicine for the treatment of chronic hepatitis B. HBV genotypes affect the disease progression and outcomes of HBV-related chronic liver disease, as well as the response to antiviral treatments. Existing data indicate a better sustained response to standard IFN-alpha in HBeAg positive genotype B patients than genotype C patients, and in genotype A patients than genotype D patients. Nevertheless, conflicting results exist regarding the response to pegylated IFN, and more studies are needed. As to HBV genetic polymorphisms, a recent study showed that an IFN sensitivity-determiningregion may not exist within the whole genome of HBV subgenotype Ba, and host factors as well as virus-host interactions may be more important than viral factors alone in determining the treatment outcomes with IFN. Regarding host genetic polymorphisms, single nucleotide polymorphisms within eukaryotic translation initiation factor 2 and MxA promoter regions may be associated with the responsiveness to standard IFN-alpha treatment in patients with HBeAg positive chronic hepatitis B. In the foreseeable future, individualized chronic hepatitis B treatment algorithms should be tailored to host (immune status, ALT level and genomic polymorphisms), virus (HBeAg status, HBV DNA level, genotype, precore/basal core promoter mutants and pre-S deletion mutant) as well as liver disease status (hepatitis activity and fibrosis stage).

Entecavir is a potent anti-HBV drug superior to lamivudine: experience from clinical trials in China

Infection with the hepatitis B virus (HBV) can result in chronic hepatitis B (CHB) in many patients. Patients with CHB require regular screening and monitoring to facilitate disease surveillance and to determine if/when treatment is indicated. The current goal of CHB treatment is sustained viral suppression with the aim of reducing or preventing hepatic injury and disease progression. Effective anti-HBV therapy is now available that can suppress, but not eradicate, HBV replication. Among the currently licensed and approved anti-HBV nucleos(t)ides, entecavir demonstrates a potent anti-HBV activity and a low rate of emergence of drug resistance, with good safety and tolerability profiles. These excellent pharmacological characteristics were assessed both in large international clinical trials and in separate studies in China. This article presents results from Phase II and Phase III trials involving 876 Chinese patients with CHB. The results of these studies suggest that entecavir should be recommended as a first-line choice among the currently available anti-HBV nucleos(t)ides.

Hepatitis B virus infection

Hepatitis B virus (HBV) infection is a worldwide health problem and may cause acute, fulminant, chronic hepatitis, liver cirrhosis, or hepatocelullar carcinoma (HCC). Infection with HBV in infancy or early childhood may lead to a high rate of persistent infection (25-90%), while the rates are lower if infection occurs during adulthood (5-10%). In most endemic areas, infection occurs mainly during early childhood and mother-to-infant transmission accounts for approximately 50% of the chronic infection cases. Hepatitis B during pregnancy does not increase maternal mortality or morbidity or the risk of fetal complications. Approximately 90% of the infants of HBsAg carrier mothers with positive hepatitis B e-antigen (HBeAg) will become carriers if no immunoprophylaxis is given. Transplacental HBeAg may induce a specific non-responsiveness of helper T cells and HBcAg. Spontaneous HBeAg seroconversion to anti-HBe may develop with time but liver damage may occur during the process of the immune clearance of HBV and HBeAg. Mother-to-infant transmission of HBV from HBeAg negative but HBsAg positive mothers is the most important cause of acute or fulminant hepatitis B in infancy. Although antiviral agents are available to treat and avoid the complications of chronic hepatitis B, prevention of HBV infection is the best way for control. Screening for maternal HBsAg with/without HBeAg, followed by three to four doses of HBV vaccine in infancy and hepatitis B immunoglobulin (HBIG) within 24h of birth is the most effective way to prevent HBV infection. In areas with a low prevalence of HBV infection or with limited resources, omitting maternal screening but giving three doses of HBV vaccine universally in infancy can also produce good protective efficacy. The first universal HBV immunisation programme in the world was launched in Taiwan 22 years ago. HBV infection rates, chronicity rates, incidence of HCC and incidence of fulminant hepatitis in children have been effectively reduced.

Viremia profiles in children with chronic hepatitis B virus infection and spontaneous e antigen seroconversion

BACKGROUND & AIMS

This study investigated the viremia profiles in children with chronic hepatitis B virus (HBV) infection and spontaneous hepatitis B e antigen (HBeAg) seroconversion.

METHODS

Fifty-eight children with chronic HBV infection met the following criteria: normal alanine aminotransferase (ALT) level at enrollment, followed up for more than 10 years, no antiviral treatment, and having undergone spontaneous HBeAg seroconversion during follow-up evaluation. They were grouped according to the post-HBeAg seroconversion HBV-DNA levels: (1) low viremia: transient or never 10(4) copies/mL or greater (n=35) (2) fluctuating high viremia: 10(4) copies/mL or greater at least twice at intervals more than 1 year apart (n=23). Abdominal sonography, ALT, and HBV-DNA levels were assessed annually. Another 14 nonseroconverted children served as controls. The precore mutant (nt1896) and genotypes were examined.

RESULTS

The initial HBV-DNA level of the 58 seroconverters was 10(8.4+/-1.0) copies/mL and decreased to 10(2.9+/-2.0) copies/mL at the end of follow-up period. Their mean ages at enrollment, at peak HBV-DNA, at peak ALT, at HBeAg seroconversion, and at final follow-up were 7.0 +/- 3.7, 13.4 +/- 5.8, 16.3 +/- 6.0, 17.2 +/- 5.8, and 23.7 +/- 4.1 years, respectively. The precore mutant appeared more often in the fluctuating-high-viremia group than in the low-viremia group (60.9% vs 22.9%, P=.004). HBV genotypes had no effect on the viremia profiles. After HBeAg seroconversion, none had persistent abnormal ALT levels.

CONCLUSIONS

Generally, these young seroconverters had decreased viral loads, normal ALT levels, and uneventful courses after HBeAg seroconversion. A longer follow-up period is necessary to elucidate the significance of HBeAg seroconversion occurring in childhood and young adulthood.

Chronic hepatitis B: a global health problem requiring coherent worldwide treatment strategies

Chronic hepatitis B virus infection, a major cause of end-stage liver disease and hepatocellular carcinoma, is a worldwide health concern. While the past two decades have brought major advances in the availability of treatments to help delay or prevent these outcomes, treatment of chronic hepatitis B remains a serious challenge, not least due to the ability of the virus to remain in hepatocyte nuclei as a source of potential reactivation-hence the term chronic hepatitis B infection. This article reviews the current treatments available and suggests a framework for a rational approach to managing the disease.

Optimal duration of therapy in HBV-related cirrhosis

It is estimated that one-third of the world's population has been exposed to hepatitis B virus and that 300-400 million people have chronic hepatitis B. In areas of the world where hepatitis B infection is endemic, this chronic viral infection is a major cause of premature morbidity and mortality related to hepatocellular carcinoma (HCC) and complications of end-stage liver disease. Recent data from population-based studies suggest that the level of viral replication in chronic hepatitis B is an independent predictor of the future complications of the disease; patients with hepatitis B viral DNA titres >10(4) copies/mL (especially those with titres >10(5) copies) have a significantly greater risk of developing HCC and cirrhosis. There is also recent evidence that treatment with antiviral therapy in patients with chronic hepatitis B who have advanced hepatic fibrosis is associated with a reduction in the risk of decompensation of liver disease and HCC. Several new antiviral medications have been recently approved for the treatment of chronic hepatitis B. Several recent position statements and practice guidelines have recommended treatment of patients with chronic hepatitis B with oral antiviral medications. However, there remains some disagreement as to the threshold of viral load before treatment should be initiated and the optimal duration of therapy in patients with cirrhosis due to hepatitis B. This article describes the current recommendations regarding therapy in this group of patients and suggests some criteria for treatment of patients with chronic hepatitis B-related cirrhosis or advanced hepatic fibrosis.

Telbivudine: a new option for the treatment of chronic hepatitis B

Chronic hepatitis B virus (HBV) infection affects > 350 million individuals worldwide. Chronic hepatitis B is associated with complications of end-stage liver disease, including cirrhosis and hepatocellular carcinoma. HBV replication is the best predictor of liver disease progression to cancer, and antiviral therapy may diminish or halt this unfavorable outcome. Six drugs have been approved for the treatment of chronic hepatitis B: interferon-alpha(2b), pegylated interferon-alpha(2a), lamivudine, adefovir, entecavir and telbivudine. Most agents designed to target hepatitis B are hindered by the development of resistance, poor tolerability or limited efficacy; therefore, new agents and treatment strategies are needed. Telbivudine is the latest approved anti-HBV agent; it is an orally administered nucleoside analog that selectively inhibits HBV replication. It has demonstrated potent activity against HBV in Phase III clinical studies, with good tolerance, lack of mitochondrial toxicity and no dose-limiting side effects.

Assessing routine and serum markers of liver fibrosis in CHB patients using parallel and serial interpretation

OBJECTIVE

The purpose of this study was to determine the cut-offs of serum biomarkers of liver fibrosis in HBsAg-positive patients by receiver operating characteristic (ROC) curves, and to determine the validity of these markers in parallel and serial interpretation.

METHODS

This study included 444 HBsAg-positive patients who had liver biopsy performed between January 1, 2003 and March 31, 2006. Some routine and clinical chemistry tests were run, and the stage of liver fibrosis was measured. The cut-offs of those markers were identified by using ROC curves. Sensitivity, specificity, predictive values (both positive and negative), and the Youden's index of these markers were calculated in parallel and serial interpretation.

RESULTS

The 444 patients were divided into a training group (322 patients) and a validation group (122 patients). All markers except gender, HB and TP were found to be statistically significant factors associated with significant fibrosis in the training group. The AUROC of GGT, APRI, AGE-PLT and AST in the training group were 0.772, 0.769, 0.748 and 0.700, respectively, and their sensitivities in the validation group were 65.00%, 70.00%, 75.00% and 60.00%, respectively. In parallel interpretation, the highest sensitivity was 85.00% at AGE-PLT union or logical sum AST, and in serial interpretation, the best specificity was 96.34% at GGT intersection AGE-PLT.

CONCLUSION

A few routine and serum biomarkers can be used to effectively assess most patients with HBsAg-positive CHB with and without significant liver fibrosis in parallel and serial interpretation.

Chronic hepatitis B virus carriers in the immunotolerant phase of infection: histologic findings and outcome

BACKGROUND & AIMS

The indication for histologic evaluation of the liver is controversial for patients in the immunotolerant phase of chronic hepatitis B virus (HBV) infection.

METHODS

Results of liver biopsy examination and follow-up evaluation were assessed retrospectively in 40 patients who satisfied the following criteria: presence of hepatitis B surface antigen and hepatitis B e antigen, HBV DNA level greater than 10(7) cp/mL, normal alanine aminotransferase level, absence of co-infection with other viruses, and absence of antiviral or immunosuppressive treatment.

RESULTS

On liver biopsy examination, according to the Metavir scoring system, fibrosis was absent in 20 patients, and mild (F1) in 20 patients. During a median follow-up period of 37.7 months in 31 patients, loss of tolerance was observed at a median age of 30.7 years in 12 (38%): 6 had transition to inactive disease, 3 developed chronic hepatitis, and 3 had a transient increase of alanine aminotransferase levels. Among baseline characteristics, only alanine aminotransferase levels were significantly higher in patients with subsequent loss of tolerance.

CONCLUSIONS

In patients in the immunotolerant phase of chronic HBV infection, liver biopsy examination shows only minimal changes and probably is unnecessary. Loss of tolerance, occurring at a median age of 30.7 years, is characterized by a rapid transition to an inactive carrier state in two thirds of patients, and to chronic hepatitis in one third of patients.

Lamivudine treatment in patients with chronic hepatitis B and cirrhosis

Chronic hepatitis B is a common disease and approximately 20% of infected patients with compensated cirrhosis will decompensate over 5 years. If untreated, the survival of decompensated cirrhosis is poor (15% at 5 years). The extent of hepatitis B virus (HBV) replication, as assessed by serum HBV-DNA level, is a strong predictor of the risk of disease progression and hepatocellular carcinoma. This provides a rationale for antiviral therapy to arrest progression of liver disease. Lamivudine is a pyrimidine analogue that inhibits HBV-DNA reverse transcriptase. It decreases HBV replication, normalises alanine aminotransferase levels and reduces hepatic inflammation and fibrosis in patients with chronic hepatitis B. This article will focus on the use of lamivudine in patients with HBV-cirrhosis. In patients with compensated HBV-cirrhosis, a randomised, placebo-controlled trial has shown that lamivudine significantly reduced the rate of disease progression and hepatocellular carcinoma development over a 3-year period. In patients with decompensated cirrhosis, treatment with lamivudine can produce spectacular improvements of liver function, but the improvement is slow and a clinical benefit is usually not observed until after at least 3-6 months of treatment. A major drawback of lamivudine treatment is the development of resistance, observed in 15-20% of patients after 1 year and up to 70% after 5 years of continued treatment. Thus, patients with HBV-cirrhosis treated with lamivudine should have regular monitoring of serum HBV-DNA levels and prompt institution of additional antiviral therapy if viral breakthrough is observed. Adefovir, tenofovir and entecavir have demonstrated efficacy in patients with lamivudine resistance. In patients with decompensated cirrhosis, in whom the development of resistance can be fatal, combination therapy (such as lamivudine plus adefovir) may prove more effective than monotherapy and this issue needs further study.

Major Causes of Antiviral drug Resistance and Implications for Treatment of Hepatitis B virus Monoinfection and Coinfection with HIV

The two key events in the life-cycle of the hepatitis B virus (HBV) involve (1) the generation from viral genomic DNA of the covalently closed circular DNA transcriptional template, and (2) the reverse transcription of the viral pregenomic RNA to form the HBV DNA genome. Diversity in the HBV genome is ensured by the low fidelity of the viral reverse transcriptase (rt). Particular selection pressures such as antiviral therapy readily select out escape mutants from this pre-existing quasispecies pool. Antiviral drug resistance in chronic hepatitis B can be caused by many factors, including the viral mutation frequency, the intrinsic mutability of the antiviral target site, the selective pressure exerted by the drug, the magnitude and rate of virus replication, the overall replication fitness of the mutant, the genetic barrier of the >compound and the availability of replication space. In the setting of HIV coinfection, the rate of replication is increased by one to two orders of magnitude, accelerating the emergence of drug resistance in this setting. The HBV genome is arranged into frame-shifted and overlapping reading frames in such a manner that antiviral drug-resistance-associated changes in the rt can result in changes in the viral envelope protein. These HBV isolates with altered surface antigens exhibit reduced binding of specific and neutralizing antibody and so have diagnostic and public health implications, especially in the setting of HIV coinfection where the risk of transmission is increased. Thus, prevention of resistance requires the adoption of strategies that effectively control virus replication, including the use of combination chemotherapy.

The Epidemiology, Natural History and Prevention of Hepatitis B: Implications of HIV Coinfection

Approximately 350 million people have chronic hepatitis B infection, a leading cause of cirrhosis and hepatocellular carcinoma (HCC). Patients who are infected through parenteral or sexual transmission are also at risk for acquisition of HIV. Concomitant HIV infection can lead to an increased risk of morbidity and mortality from hepatitis B virus (HBV)-related cirrhosis, end-stage liver disease and HCC. This review will focus on the epidemiology, natural history and prevention of HBV infection and the modulating effect of HIV on the clinical expression of HBV disease.

Treatment of Chronic Hepatitis B

Hepatitis B virus (HBV) infection is the leading cause of chronic liver disease and hepatocellular carcinoma worldwide. Approximately 350 million individuals are infected with HBV and >500,000 deaths per year can be attributed to HBV. Although universal vaccination has reduced HBV incidence in many countries, it still remains a major public health problem, especially in parts of Asia and Africa. Improved understanding of HBV virology and virus-host interactions has revolutionized chronic hepatitis B therapy in the past two decades. Development of oral nucleoside/nucleotide analogues heralds a new era of safe and effective treatment of this disease. On the basis of these advances, new guidelines for the treatment of chronic hepatitis B have been issued. Successful long-term treatment of chronic hepatitis B may rest on combination therapy that is based on molecular approaches targeting various stages of the HBV life-cycle. In this review, we summarize the current modalities and highlight important issues in the treatment of chronic hepatitis B monoinfection.

Dynamics of hepatitis B e antigen index ratio correlate with treatment response in chronic hepatitis B patients

BACKGROUND/AIM

Hepatitis B e antigen (HBeAg) seroconversion is an important event in the natural history of chronic hepatitis B virus (HBV) infection. Whether early dynamics of HBeAg index ratio could predict therapeutic endpoint of HBeAg seroconversion in patients receiving lamivudine remains unclear and thus deserves investigation.

METHODS

A total of 52 patients (males/females, 40/12; mean age, 31.1+/-7.5 years) with HBeAg-positive chronic hepatitis B and serum alanine aminotransferase (ALT) level > or = 5 x upper limit of normal were enrolled. They received daily 100 mg lamivudine for at least 1 year. Pretreatment HBeAg index ratio and the dynamics during treatment [early serologic response (ESR) and serologic breakthrough (SB)] between responders and non-responders were compared.

RESULTS

Of these 52 patients, mean pretreatment serum ALT level was 580 IU/l and baseline HBeAg index ratio (S/N) was 37.9. The overall 1-year on-treatment combined response rate was 50%. By using linear regression analysis, HBeAg index ratio was positively correlated with serum HBV DNA level (Pearson's correlation coefficient: 0.62, P<0.0001). By using multivariate logistic regression analysis, ESR could predict the success of treatment response (P=0.0302), and SB had a 90% positive predictive value of treatment failure.

CONCLUSIONS

HBeAg index ratio is closely correlated with serum HBV DNA level, and the dynamics of HBeAg index ratio may predict 1-year on-treatment combined response to lamivudine in HBeAg-positive chronic hepatitis B patients.

Long-term outcome after prophylactic lamivudine treatment on hepatitis B virus reactivation in non-Hodgkin's lymphoma

Hepatitis B virus (HBV) reactivation is the frequent complication after cytotoxic chemotherapy in HBsAg-positive non-Hodgkin's lymphoma (NHL) patients. Pre-chemotherapy viral load may be a risk factor and HBeAg-positive status is associated with increased viral load. The aim of this study was to investigate the long-term treatment outcome of lamivudine in preventing HBV reactivation and its associated morbidity according to HBeAg status. Twenty-four adult HBsAg-positive NHL patients were taken 100 mg of lamivudine daily before the initiation of chemotherapy. The median duration of lamivudine therapy was 11.5 months (range: 1-54 months) and the median number of chemotherapy cycles was 6 (range: 1-16 cycles). The steroid containing chemotherapy regimens were used in 18 patients (75%), and the anti-CD20 monoclonal antibody containing chemotherapy regimen was used in 6 patients (25%). Four patients received autologous peripheral blood stem cell transplantation without resultant HBV reactivation. Hepatitis related to HBV reactivation was developed in 1 patient among 14 HBeAg-positive patients and no one among 10 HBeAg-negative. One patient developed HBV reactivation after lamivudine withdrawal, and 4 patients developed the YMDD (tyrosine-methionine-aspartate-aspartate) mutation during lamivudine therapy. There were no statistical differences in HBV reactivation rate during chemotherapy according to the HBeAg status. Our results demonstrate that lamivudine should be considered preemptively before the chemotherapy for all HBsAg-positive NHL patients to prevent HBV reactivation, regardless of pre-chemotherapy HBeAg status. Finally, compared with the chronic hepatitis B patients, similar rate of HBV reactivation after lamivudine withdrawal and development of YMDD mutation was observed in NHL patients.

A prophylactic approach for bone marrow transplantation from a hepatitis B surface antigen-positive donor

It has been accepted that bone marrow transplantation (BMT) is the only curative therapeutic option for certain hematologic malignancies. The southeast Asia region is an endemic area of hepatitis B virus (HBV) infection; thus, BMT using a hepatitis B surface antigen (HBsAg)-positive donor is occasionally unavoidable. Organ transplantation using a HBsAg-positive donor can lead to post-transplantation de novo HBV infection and severe HBV-related hepatitis if no effective prophylactic measures are taken prior to and after transplantation. In this report, a four-level approach was designed for a patient with chronic myeloid leukemia, beginning with a booster HBV vaccination before performing BMT with a HBsAg-positive donor. Prior to BMT, the HBV viral load of the donor was reduced to an undetectable level by antiviral therapy. After BMT, hepatitis B immunoglobulin was administered intramuscularly for 1 wk together with a long-term antiviral drug, lamivudine. One year after discontinuation of lamivudine, the patient is still free of HBV infection.

Fatal liver failure caused by reactivation of lamivudine-resistant hepatitis B virus: A case report

We present a case of fetal liver failure caused by the activation of lamivudine-resistant hepatitis B virus (HBV) nine months after lamivudine treatment. A 57-year old man visited our hospital for the treatment of decompensated chronic hepatitis B. Lamivudine was started in December 2001. Subsequently, serum HBV was negative for HBV DNA with seroconversion from HBeAg to anti-HBe and improvement of liver function. However, HBV DNA and HBeAg were again detected in September 2002. He was complicated by breakthrough hepatitis and admitted to our hospital in November for severely impaired liver function. Vidarabine treatment was started and serum HBV DNA and alanine aminotransferase (ALT) decreased transiently. However, after the start of α-interferon treatment, HBV DNA level increased and liver function deteriorated. He died 1 mo after admission. An analysis of amino acid sequences in the polymerase region revealed that rtM204I/V with rtL80I/V occurred at the time of viral breakthrough. After the start of antiviral treatment, rtL180M was detected in addition to rtM204I/V and rtL80I/V, and became predominant in the terminal stage of the disease. HBV clone with a high replication capacity may be produced by antiviral treatment leading to the worsening of liver function. Antiviral therapy for patients with breakthrough hepatitis in advanced liver disease should be carefully performed.

Novel approaches towards conquering hepatitis B virus infection

Currently approved treatments for hepatitis B virus (HBV) infection include the immunomodulatory agent, IFN-α, and nucleos(t)ide analogues. Their efficacy is limited by their side effects, as well as the induction of viral mutations that render them less potent. It is thus necessary to develop drugs that target additional viral antigens. Chemicals and biomaterials by unique methods of preventing HBV replication are currently being developed, including novel nucleosides and newly synthesized compounds such as capsid assembling and mRNA transcription inhibitors. Molecular therapies that target different stages of the HBV life cycle will aid current methods to manage chronic hepatitis B (CHB) infection. The use of immunomodulators and gene therapy are also under consideration. This report summarizes the most recent treatment possibilities for CHB infection. Emerging therapies and their potential mechanisms, efficacy, and pitfalls are discussed.

Interferon therapy in HBeAg positive chronic hepatitis reduces progression to cirrhosis and hepatocellular carcinoma

BACKGROUND/AIMS

The long-term outcomes of interferon-alpha (IFN-alpha) therapy in hepatitis B e antigen (HBeAg) seropositive patients remain controversial. This study was conducted to address this issue.

METHODS

The long-term outcomes were compared in 233 IFN-treated patients and 233 well-matched untreated controls.

RESULTS

The cumulative incidence at the end of 15 years of follow-up (median 6.8 years, range 1.1-16.5 years) in the IFN-treated patients and controls was: HBeAg seroconversion 74.6% vs. 51.7% (P=0.031); hepatitis B surface antigen (HBsAg) seroclearance 3% vs. 0.4% (P=0.03); cirrhosis 17.8% vs. 33.7% (P=0.041); and hepatocellular carcinoma (HCC) 2.7% vs. 12.5% (P=0.011). Significant reduction of HCC was only observed in patients with pre-existing cirrhosis (P<0.01). Compared with untreated controls with persistent HBeAg, HBeAg seroconverters in untreated and IFN-treated group showed significantly lower incidence of cirrhosis and HCC (P=0.003-0.031), while non-seroconverters of IFN-treated group had marginally significant lower incidence of cirrhosis (P=0.065). Multivariate analysis showed that IFN therapy, HBeAg seroconversion and genotype B HBV infection are independent factors for better long-term outcomes.

CONCLUSIONS

IFN therapy reduces cirrhosis and HCC development.

Characterization of viral kinetics in patients with hepatitis B e antigen-positive chronic hepatitis B

A study was conducted during a 1 year follow-up to characterize the viral kinetics in hepatitis B e antigen (HBeAg)-positive chronic hepatitis B and to develop a model of predicting the probability of spontaneous HBeAg seroconversion. Fifty-seven patients with HBeAg-positive chronic hepatitis B were enrolled with monthly follow-ups from three Phase III clinical trial placebo groups. According to serial viral loads, 30 patients (52.6%) with the stationary pattern maintained stable HBV DNA levels with fluctuations of less than 1.5 log copies/ml. Twenty patients (35.1%) with the declining pattern exhibited a spontaneous decline of more than 1.5 log copies/ml without a following rebound of at least 1.5 log copies/ml. The remaining seven patients (12.3%) had the wavering pattern. Both declining and wavering patterns, when compared with the stationary pattern, had significantly higher hepatic necroinflammation in terms of ALT and Knodell scores at the baseline and peak ALT levels during the follow-up period. The declining pattern had a significantly better clinical outcome in terms of the lowest final HBV DNA and a reduction in the necroinflammatory score after 1 year. Furthermore, the declining pattern had a favorable HBeAg seroconversion rate (40%) compared with the wavering (14.3%) and stationary patterns (0%). A regression equation, incorporating simultaneous serum bilirubin, ALT, and HBV DNA levels, predicted the probability of HBeAg seroconversion with a sensitivity of 76.8% and a specificity of 74.7%. In conclusion, different viral kinetic patterns in patients with chronic hepatitis B implicate distinct clinical significance and immunologic perspective.

Entecavir: a review of its use in chronic hepatitis B

Entecavir (Baraclude) is a novel nucleoside analogue of 2'-deoxyguanosine whose intracellular triphosphate form inhibits replication of the hepatitis B virus (HBV). In large, randomised, double-blind, phase III clinical trials in patients with chronic HBV infection, oral entecavir 0.5 or 1.0mg once daily for up to 96 weeks was superior to lamivudine 100 mg/day in improving hepatic histology, normalising aminotransferase levels and suppressing viraemia to levels undetectable by polymerase chain reaction (PCR) assay in nucleoside-naive hepatitis B e antigen (HBeAg)-negative (precore or core promoter mutants) and/or HBeAg-positive patients, and in lamivudine-refractory (persistent viraemia during lamivudine therapy) HBeAg-positive patients. In addition, the tolerability profile of entecavir was generally similar to that of lamivudine. Thus, entecavir is a primary option in the treatment of chronic HBV infection in both nucleoside-naive and lamivudine-refractory patients.

Early mortality in taiwanese lamivudine-treated patients with chronic hepatitis B-related decompensation: evaluation of the model for end-stage liver disease and index scoring systems as prognostic predictors

BACKGROUND

Both Model for End-stage Liver Disease (MELD) and Index scores have been used to predict mortality in patients with end-stage liver disease and cirrhosis in Western countries.

OBJECTIVES

This study aimed to determine mortality rates, identify prognostic indicators, and determine the usefulness of these 2 scoring systems in predicting short-term (6-month) survival in Taiwanese patients with chronic hepatitis B (CHB)-related decompensation who were treated with lamivudine.

METHODS

This study was conducted at the Kaohsiung Medical University Hospital and the Kaohsiung Municipal Hsiao-Kang Hospital, Kaohsiung, Taiwan. Eligible patients were aged 18 to 85 years with CHB with related decompensation (with either serum total bilirubin level, >or=3 mg/dL or prolonged prothrombin time, >or=3 seconds) and were treatment naive. All patients were treated with lamivudine 100 mg PO (tablet) once daily; surviving patients were treated for at least 6 months. The clinical data, including hepatitis B surface antigen, hepatitis B e antigen, and hepatitis B virus (HBV) DNA, were measured before treatment. Pre-treatment MELD and Index scores were calculated for all patients.

RESULTS

Ninety-six patients were enrolled (79 men, 17 women; mean [SD] age, 44.5 [15.2] years). Thirteen (13.5%) patients died within 6 months. Higher international normalized ratio (INR) for prothrombin time, lower albumin level, and higher HBV DNA level (>or=10(5) copies/mL) were factors significantly associated with death. The areas under the receiver operating characteristic curve for predicting survival by the MELD and Index scores were 0.822 and 0.788, respectively. Albumin level, which was not included in the scoring systems, also was found to be a significant predictor.

CONCLUSIONS

: We found that with a 13.5% mortality rate, albumin, INR, and HBV DNA levels were good prognostic indicators in Taiwanese patients with CHB-related decompensation treated with lamivudine therapy. The MELD and Index scoring systems were good predictors of 6-month survival in the patients in this study.

Therapeutic effect of hepatitis B surface antigen-antibody complex is associated with cytolytic and non-cytolytic immune responses in hepatitis B patients

To study the responses of chronic hepatitis B patients to yeast-derived HBsAg-HBIG complexes (YIC) and the mechanisms involved, twenty HBeAg-positive chronic hepatitis B patients were immunized with 60microg of YIC or alum as the control at 4-week intervals, for 24 weeks. Five of ten patients responded to 60microg YIC immunization showing > or =2 logs decrease of serum HBV DNA with loss or marked reduction of HBeAg and appearance of anti-HBe; two of these patients developed anti-HBs. Flares of alanine aminotransferase were observed in 4 of the 5 responders, and in 2 out of 10 control patients. HBsAg-stimulated peripheral blood mononuclear cells (PBMCs) secreted Th1/Th2 cytokines around 24 weeks after immunization. Dendritic cells incubated with YIC showed the highest levels of IL-12 secretion and up-regulation of functional markers. Thus, the therapeutic effect of YIC is associated with cytolytic and non-cytolytic responses in patients.

[Treatment of viral hepatitis (I). Treatment of chronic hepatitis B]

In the past 25 years remarkable progress has been made in our understanding of the natural history of chronic HBV. The infection is now perceived as having three consecutive phases: immune tolerance, immune clearance, and inactive carrier status, with possible reactivation episodes. Accumulating evidence indicates that antiviral therapy can prevent progression of HBV-related liver disease, particularly among patients with sustained response. Five agents are now approved for therapy of chronic hepatitis B: interferon-alpha (standard and pegylated), lamivudine, adefovir and entecavir. All five drugs are effective in suppressing HBV DNA levels and improving serum alanineaminotransferase levels and hepatic histology, but it is still unclear who should be treated, with which agent (or combination of agents), for how long, and what endpoints measure the success or failure of treatment. Until a drug therapy results in lasting virological remission in most patients after a reasonably short period of treatment, individualized treatment decisions will remain key to maximizing efficacy, and chronic HBV infection will continue to be treated as a liver disease rather than as an infectious disease.

Efficacy of thymosin alpha-1 and interferon alpha in treatment of chronic viral hepatitis B: a randomized controlled study

AIM

To observe the efficiency and safety of thymosin-alpha1 treatment in patients with hepatitis B e antigen (HBeAg) and HBV DNA positive chronic hepatitis.

METHODS

Sixty-two patients were randomly divided into groups A and B. The patients in group A received subcutaneous injection of 1.6 mg thymosin-alpha1, twice a week (T-alpha1 group) for six months, and the patients in group B received 5 MU interferon alpha (IFN-alpha) each day for fifteen days, then three times weekly (IFN-alpha group) for six months. The results between two groups treated with and the group untreated with IFN-alpha which was followed up for 12 mo (historical control group consisting of 30 patients) were compared, and three groups were comparable between each other (P>0.05) at baseline (age, sex, clinical history, biochemical, and serological parameters).

RESULTS

At the end of treatment, complete response, which was defined as alanine aminotransferase (ALT) normalization and HBV DNA and HBeAg loss, occurred in 9 of 29 (31.0%) patients in the T-alpha1 group and in 15 of 33 (45.5%) patients in the IFN-alpha group (chi2=1.36, P>0.05). After a follow-up period of six months, a complete response was observed in 14 of 29 (48.3%) patients in the T-alpha1 group and in 9 of 33 (27.3%) patients in the IFN-alpha group (chi2=2.93, P>0.05). Compared with the results observed in the historical control (HC) group untreated with IFN-alpha which was followed up for 12 mo, the rate of complete response was significantly higher in IFN-alpha group at the end of therapy (1 of 30 vs 15 of 33, chi2=14.72, P<0.001) and in the T-alpha1 group at the end of follow-up (1 of 30 vs 14 of 29, chi2=15.71, P<0.001). In T-alpha1 and IFN-alpha treatment groups, the area under (the plasma concentration time) curve (AUC) of negative HBV DNA and HBeAg was 34%, 17%, 31% and 19% smaller than that in the HC group. By the end of the follow-up period, the proportions of ALT normalization and negative HBV DNA in the T-alpha1 group were significantly higher than those in the IFN-alpha and HC groups. The odds of ALT normalization and negative HBV DNA at the end of the follow-up was three-fold higher in the T-alpha1 group than in the IFN-alpha group. Unlike IFN-alpha, T-alpha1 was well tolerated by all patients, and no side effects appeared in T-alpha1 group.

CONCLUSION

The results suggest that a 6-mo course of T-alpha1 therapy is effective and safe in patients with chronic hepatitis B. T-alpha1 is able to reduce HBV replication in patients with chronic hepatitis B. Furthermore, T-alpha1 is better tolerated than IFN-alpha and can gradually induce more sustained ALT normalization and HBV DNA and HBeAg loss. However, a response rate of 48.3% is still less ideal. A more effective therapeutic approach warrants further study.

Canadian consensus on medically acceptable wait times for digestive health care

BACKGROUND

Delays in access to health care in Canada have been reported, but standardized systems to manage and monitor wait lists and wait times, and benchmarks for appropriate wait times, are lacking. The objective of the present consensus was to develop evidence- and expertise-based recommendations for medically appropriate maximal wait times for consultation and procedures by a digestive disease specialist.

METHODS

A steering committee drafted statements defining maximal wait times for specialist consultation and procedures based on the most common reasons for referral of adult patients to a digestive disease specialist. Statements were circulated in advance to a multidisciplinary group of 25 participants for comments and voting. At the consensus meeting, relevant data and the results of voting were presented and discussed; these formed the basis of the final wording and voting of statements.

RESULTS

Twenty-four statements were produced regarding maximal medically appropriate wait times for specialist consultation and procedures based on presenting signs and symptoms of referred patients. Statements covered the areas of gastrointestinal bleeding; cancer confirmation and screening and surveillance of colon cancer and colonic polyps; liver, biliary and pancreatic disorders; dysphagia and dyspepsia; abdominal pain and bowel dysfunction; and suspected inflammatory bowel disease. Maximal wait times could be stratified into four possible acuity categories of 24 h, two weeks, two months and six months.

FUTURE DIRECTIONS

Comparison of these benchmarks with actual wait times will identify limitations in access to digestive heath care in Canada. These recommendations should be considered targets for future health care improvements and are not clinical practice guidelines.

RNA interference inhibits hepatitis B virus gene expression and replication in HepG2-N10 cells

OBJECTIVE

RNA interference (RNAi) refers to the phenomenon of sequence-specific degradation of homologous mRNA induced by double-stranded RNA. It has been successfully utilized to down-regulate endogenous gene expression or suppress the replication of various pathogens in mammalian cells. In this study, the effect of vector-based small interfering RNA (siRNA) promoted by pSilencer2.0-U6 inhibit hepatitis B virus (HBV) replication in cell culture was evaluated.

METHODS

Three fragments of short nucleic acids, respectively, targeting on S, X and C region of HBV genome were inserted into pSilencer vectors after they were annealed with their partly antisense strands. The recombination plasmids were pS, pX and pC. These expression plasmids were transfected into HepG2-N10 cells, a cell line which stably expresses hepatitis B virus surface antigen (HBsAg), hepatitis B virus e antigen (HBeAg) and adw2 subtype Dane particles. The effect of RNAi was evaluated from the changes of DNA, RNA and protein levels. Viral antigens were measured by ELISA. Viral mRNA was analyzed by RT-PCR. The covalent closed circular DNA and genome DNA of HBV secreted into the culture media were measured by quantitative real-time PCR. Analysis of variance was performed for the results.

RESULTS

Vector-based RNA interference could potently reduce HBsAg (pS vs pN: 47%, pX vs pN: 30%, and pC vs pN: 25%, P < 0.001) and HBeAg (pX vs pN: 57% and pC vs pN: 66%, P < 0.001) expression in cell culture. Furthermore, RT-PCR analysis showed that viral mRNAs were effectively degraded, thus eliminating the messengers for protein expression as well as templates for reverse transcription (pS and pC vs pN, P < 0.001; pX vs pN, P = 0.003). Quantitative real-time PCR analysis of HBV DNA revealed that vector-based RNA interference can inhibit HBV replication efficiently (pS, pX and pC vs pN, P < 0.001).

CONCLUSIONS

Our results indicate that RNAi can inhibit HBV gene expression and replication, and it might have the potential to revolutionize the treatment of HBV.

Recommendations and potential future options in the treatment of hepatitis B

The natural history of chronic hepatitis B should be clearly defined before appropriate recommendations for treatment can be advocated. In patients who acquire the disease in early life, the complications of chronic hepatitis B continue to occur as a result of prolonged insidious damage to the liver, even in the low viraemic phase. Treatment that ends with hepatitis B e antigen seroconversion with hepatitis B virus DNA levels just below 10(5) copies/ml may not be sufficient. Patients with mild elevation of alanine aminotransferase levels are already at considerable risk of developing complications. Treatment strategy should aim at maximal and prolonged viral suppression to the lowest possible hepatitis B virus DNA levels. Nucleotide/nucleoside analogues will become the mainstay of treatment. Future treatment strategic plans should target maximising antiviral potency and minimising the chance of drug resistance.

Diagnosis and management of chronic hepatitis B in the primary care setting

Chronic hepatitis B is a complex disease for which there are an increasing number of approved treatment options. Clinicians who strive to keep up to date on the diagnosis and treatment of hepatitis B will be in the best position to meet the challenge of managing patients with this serious infection.

Hepatitis B virus genotypes, precore and core promoter variants among predominantly Asian patients with chronic HBV infection in a Canadian center

BACKGROUND AND AIMS

The epidemiology of hepatitis B virus (HBV) infection in North America may be changing as a result of immigration from endemic countries. The purpose of this study was to determine the prevalence of HBV genotypes, precore (PC) and core promoter (CP) variants, and the proportion of patients meeting treatment criteria for HBV.

METHODS

A cross-sectional study of consecutive HBV patients attending a Canadian tertiary liver center was conducted. HBV DNA was quantified by polymerase chain reaction assay. HBV genotypes and variants were determined using a line probe assay.

RESULTS

Two hundred and seventy-two patients were enrolled; 200 were not receiving treatment at enrollment, of whom 116 were men and 84 women with a mean age 42+/-14 years. Among this group, 177 (88%) patients were Asian and 19 (10%) were Caucasian and 69 (35%) patients were hepatitis B e antigen (HBeAg) positive. Genotypes B and C were found in 42% and 50% untreated patients, respectively; while CP and PC were detected in 52% and 43% patients, respectively. Approximately 20% patients not receiving treatment (29% HBeAg positive, 14% HBeAg negative) met AASLD guidelines for antiviral therapy. If lower cutoff values for alanine aminotransferase and HBV DNA levels were used, 49% patients would qualify for treatment.

CONCLUSIONS

The vast majority of patients at a Canadian tertiary referral center were Asian. Virological and clinical characteristics of these patients reflect their country of origin. Our findings highlight the need to monitor the changing patterns of HBV infection in countries with large immigrant populations.

Hepatitis B Virus Replication and Liver Disease Progression: The Impact of Antiviral Therapy

Chronic hepatitis B virus (HBV) infection is a serious health issue worldwide. The presence of HBV replication markers — hepatitis B e antigen (HBeAg) or HBV DNA — is associated with continuing hepatitis activity or intermittent hepatitis flares and subsequent disease progression, including hepatic decompensation and development of liver cirrhosis or hepatocellular carcinoma (HCC). Long-term (>10 years) prospective studies in patients ≥30 years of age have shown that HBeAg seropositivity is associated with increased risk of disease progression, and the risk of cirrhosis and HCC begins to increase at an HBV DNA level of 104 copies/ml. Therefore, elimination of HBV, or at least sustained or maintained suppression of HBV, is the key to reducing hepatitis and thereby halting or preventing disease progression. Therapy with interferon-α or a direct antiviral agent has been shown to reduce the risk of cirrhosis and prevent further disease worsening. In both the woodchuck hepatitis model and in HBV patients, maintained suppression of HBV replication by a direct antiviral agent may reduce the progression to HCC. However, the efficacy of current antiviral therapy is still far from satisfactory. The ability to achieve a high rate of sustained or maintained HBV suppression with a low risk of drug resistance would be the ultimate goal in the treatment of chronic HBV infection.

Do we still need a liver biopsy? Are the serum fibrosis tests ready for prime time?

Liver biopsy has been in use for more than a century for diagnosis and staging of acute and chronic liver diseases. Several serum markers and panels offer the opportunity to assess the extent of liver disease noninvasively and spare some patients the risks associated with percutaneous liver biopsy, but only a few of the noninvasive serum markers allow the determination of different stages of fibrosis on a continuum similar to that achieved with liver biopsy. This article reviews the results of recent published and preliminary studies on serum markers, focusing on their comparison with liver biopsy and their clinical utility.

Non-invasive models for predicting histology in patients with chronic hepatitis B

BACKGROUND AND AIM

In contrast to chronic hepatitis C (CHC), few studies had been performed in assessing non-invasive models for predicting significant fibrosis or cirrhosis in chronic hepatitis B (CHB) patients. We aimed to evaluate non-invasive markers for diagnosing significant fibrosis/cirrhosis in patients with CHB, and to evaluate accuracy of models from CHC in CHB patients.

PATIENTS AND METHODS

Liver biopsies from consecutive treatment-naïve CHB patients were evaluated histologically by a pathologist blindly, using the Ishak score. Patients were divided randomly into a training (65%) and a validation sets (35%). Markers of fibrosis were evaluated by univariate followed by multivariate analysis in the training set. Area under receiver operating characteristics curve (AUROC) was assessed and validated in the training set. AUROC of aspartate aminotransferase (AST), AST/alanine aminotransferase (ALT) ratio, and AST-platelets ratio index (APRI) (derived from studies from CHC) in diagnosing significant fibrosis/cirrhosis were also assessed.

RESULTS

Two-hundred and eighteen CHB patients were evaluated: 83% male, 86% Chinese, 47% having significant fibrosis, 19% having cirrhosis. Platelets were the only factor significantly associated with significant fibrosis and cirrhosis at multivariate analysis but the AUROC was only modest at 0.63 and 0.73, respectively. Models derived from studies from CHC were even less accurate.

CONCLUSION

Models with non-invasive markers in predicting histology from CHC patients were unsuitable for CHB patients. No variables consisting of simple and readily available markers were able to predict cirrhosis accurately in patients with CHB.

A double-blind randomized trial of adefovir dipivoxil in Chinese subjects with HBeAg-positive chronic hepatitis B

Four hundred and eighty Chinese subjects with hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) were enrolled in a multicenter, double-blind, randomized, placebo-controlled study of adefovir dipivoxil (ADV) 10 mg once daily. There was a significant difference in reduction of serum hepatitis B virus (HBV) DNA after 12 weeks between subjects who received ADV and those who received the placebo (3.4 and 0.1 log10 copies/mL, respectively, P < .001). Further reductions in serum HBV DNA and increases in the proportion of subjects with an HBV DNA level of at most 10(5) copies/mL, with HBV DNA undetectable, and with ALT normalization were observed in ADV-treated subjects at week 52 (median HBV DNA reduction of 4.5 log(10) copies/mL, 67% with HBV DNA <or= 10(5) copies/mL, 28% with HBV DNA undetectable, and 79% with ALT normalization). Subjects who initially received ADV lost some treatment benefit after being rerandomized to the placebo in week 40. Subjects with YMDD mutant HBV at baseline had virological, biochemical, and serological responses to treatment that were similar to those of subjects with wild-type HBV. The incidence of clinically adverse events was similar in nature and severity between the treatment groups, and there was no evidence of renal toxicity. No adefovir-related HBV mutations were identified. In conclusion, treatment with ADV 10 mg daily over 52 weeks was safe and effective in Chinese subjects with HBeAg-positive CHB and did not lead to the emergence of drug resistance. The study is continuing for an additional 4 years with all subjects on open-label ADV 10 mg daily.

Entecavir for treatment of lamivudine-refractory, HBeAg-positive chronic hepatitis B

BACKGROUND & AIMS

Lamivudine treatment is associated with frequent development of resistant hepatitis B virus (HBV) and loss of treatment benefit. In preclinical and phase II studies, entecavir demonstrated potent antiviral activity against lamivudine-resistant HBV.

METHODS

In this phase III, double-blind trial, hepatitis B e antigen-positive patients who were refractory to lamivudine therapy (persistent viremia or documented YMDD mutations while receiving lamivudine) were randomized to switch to entecavir 1 mg daily (n = 141) or continue lamivudine 100 mg daily (n = 145) for a minimum of 52 weeks. Two coprimary end points were assessed at 48 weeks: histologic improvement and a composite end point (HBV branched DNA <0.7 MEq/mL and alanine aminotransferase [ALT] <1.25 times the upper limit of normal).

RESULTS

Histologic improvement occurred in 55% (68/124) of entecavir-treated vs 28% (32/116) of lamivudine-treated patients (P < .0001). More patients on entecavir than lamivudine achieved the composite end point: 55% (77/141) vs 4% (6/145), respectively (P < .0001). Mean change from baseline in HBV DNA was -5.11 log(10) copies/mL for entecavir-treated patients and -0.48 log(10) copies/mL for lamivudine-treated patients (P < .0001). Virologic rebound because of entecavir resistance substitutions occurred in 2 of 141 of entecavir-treated patients, and genotypic evidence of resistance was detected in 10 patients. The safety profile of entecavir was comparable to lamivudine with fewer ALT flares on treatment.

CONCLUSIONS

In patients with lamivudine-refractory chronic hepatitis B, switching to entecavir provides superior histologic improvement, viral load reduction, and ALT normalization compared with continuing lamivudine, with a comparable adverse event profile.

Chronic hepatitis B: current testing strategies

The worldwide burden of hepatitis B mandates accurate and timely diagnosis of patients infected with the hepatitis B virus (HBV) and the use of treatment strategies derived from evidence-based guidelines. HBV is a DNA virus that produces a series of viral protein products circulating HBV DNA. Serologic and nucleic acid testing are critical to disease prevention and treatment objectives. Information from such testing helps determine patients' infectivity and immune status, appropriate monitoring strategies, and the efficacy of treatment, as well as providing data that contributes to a better understanding of the natural history and epidemiology of the disease. This article reviews the clinical use of state-of-the-art serologic and nucleic acid tests, including the relevance of hepatitis B e antigen and antibody and HBV DNA measurements as markers of disease activity. Viral load can be used to distinguish between active and inactive disease, define response to therapy, and detect the development of antiviral resistance. Some recent reports have suggested that high viral load is associated with poorer patient outcomes (eg, more rapid progression to cirrhosis and a higher incidence of hepatocellular carcinoma). Durable suppression of HBV DNA is evolving to become the primary goal of therapy, although all currently licensed medications have used histology as the primary end point of therapy. Suggested frequencies for HBV DNA monitoring are presented.