Treatment of chronic hepatitis D

Cell Culture Models for the Study of Hepatitis D Virus Entry and Infection

Chronic hepatitis D is one of the most severe and aggressive forms of chronic viral hepatitis with a high risk of developing hepatocellular carcinoma (HCC). It results from the co-infection of the liver with the hepatitis B virus (HBV) and its satellite, the hepatitis D virus (HDV). Although current therapies can control HBV infection, no treatment that efficiently eliminates HDV is available and novel therapeutic strategies are needed. Although the HDV cycle is well described, the lack of simple experimental models has restricted the study of host–virus interactions, even if they represent relevant therapeutic targets. In the last few years, the discovery of the sodium taurocholate co-transporting polypeptide (NTCP) as a key cellular entry factor for HBV and HDV has allowed the development of new cell culture models susceptible to HBV and HDV infection. In this review, we summarize the main in vitro model systems used for the study of HDV entry and infection, discuss their benefits and limitations and highlight perspectives for future developments.

Targeting the Host for New Therapeutic Perspectives in Hepatitis D

Hepatitis D virus (HDV) is a small satellite virus of hepatitis B virus (HBV) requiring HBV infection to complete its life cycle. It has been recently estimated that 13% of chronic HBV infected patients (60 million) are co-infected with HDV. Chronic hepatitis D is the most severe form of viral hepatitis with the highest risk to develop cirrhosis and liver cancer. Current treatment is based on pegylated-interferon-alpha which rarely controls HDV infection and is complicated by serious side effects. The development of novel antiviral strategies based on host targeting agents has shown promising results in phase I/II clinical trials. This review summarizes HDV molecular virology and physiopathology as well as new therapeutic approaches targeting HDV host factors.

Decreasing seroprevalence of anti-hepatitis D virus antibodies in the antiviral era with inverse association with hepatitis B virus DNA, Taiwan, 2006 to 2019

We examined the seroprevalence change of anti-hepatitis D virus (HDV) antibodies in Taiwan from 2006 to 2019. A total of 1147 patients who had chronic hepatitis B virus (HBV) infection were assessed. Of them, 51 (4.4%) were positive for anti-HDV antibodies. Comparison between anti-HDV-positive and negative groups was performed to examine clinical and virological factors related to anti-HDV positivity. It was found that the median HBV-DNA concentration was 1.6 × 10⁵  IU/mL (range, <20-4.5 × 10¹⁰  IU/mL) and <20 IU/mL (range, <20-2.0 × 10⁹  IU/mL) for patients with negative and positive anti-HDV antibodies, respectively (P < .001). In addition, a progressive year-to-year decrease of anti-HDV seroprevalence was unveiled. For patients who had HBV-DNA >15 000 IU/mL, the year-to-year (calculated every 2 years) seropositive rates of anti-HDV were 10.0%, 7.9%, 0.7%, 0.3%, 0%, 0%, and 0% (P < .001). For patients who had HBV-DNA <15 000 IU/mL, the year-to-year seropositive rates were 18.6%, 12.8%, 7.8%, 5.0%, 7.3%, 8.0%, and 3.7% (P < .001). In conclusion, seropositive of anti-HDV was inversely associated with HBV-DNA levels. A progressive decrease of anti-HDV seroprevalence was found with no anti-HDV-positive cases detected in high HBV-DNA patient group after 2014.

HBsAg kinetics in chronic hepatitis D during interferon therapy: on-treatment prediction of response

BACKGROUND

Therapy of chronic hepatitis D with Interferon is successful when testing for HDV-RNA turns negative. This end-point is disputed.

AIM

To assess the role of serum hepatitis B surface antigen (HBsAg) in the clearance of HDV-RNA in pegylated interferon (Peg-IFN)-treated chronic hepatitis D (CHD).

METHODS

Sixty-two patients with CHD, treated with Peg-IFN, were considered. The patients belonged to three groups: 14 patients cleared the HBsAg and HDV-RNA (responders, R), 12 cleared the HDV-RNA remaining positive for HBsAg (partial responders, PR) and 36 cleared neither the HBsAg nor the HDV-RNA (nonresponders, NR).

RESULTS

In responders, at baseline the median value (mv) of HBsAg and HDV-RNA was 1187 and 188 663 IU/mL. By month 6 of therapy, HBsAg declined to less than 1000 IU/mL and HDV-RNA was undetectable in 12 patients. In NR, the pre-therapy median value of HBsAg and HDV viremia was 6577 and 676 319 IU/mL. There was no significant reduction of antigen at month 6; after a decline, HDV-RNA rebounded to baseline levels. In PR, the median value of baseline HBsAg was 7031 IU/mL; it declined at month 6 in the majority. HDV-RNA progressively declined from an initial median value of 171 405 IU/mL. HBsAg <1000 IU/mL at month 6 discriminated responders and PR from NR (P < 0.001). By ROC curve, the threshold of 0.105 log reduction of HBsAg associated with 1.610 log reduction of HDV-RNA from baseline to month 6 predicted the clearance of this marker.

CONCLUSIONS

A reduction of serum HBsAg is mandatory for the definitive clearance of the HDV-RNA. Quantitative HBsAg may predict the long-term response to Peg-IFN therapy and provide a guide to prolong or stop treatment.

Interferon alpha-2b therapy in chronic hepatitis delta

BACKGROUND

Approximately 5% of hepatitis B virus (HBV) carriers are coinfected with hepatitis D virus (HDV). HBV/HDV coinfection is a major cause of cirrhosis and end stage liver disease in chronic HBsAg carriers. The only approved therapy for chronic hepatitis delta is interferon alpha (IFN α) in either pegylated or conventional forms. Although higher doses and longer durations of IFN α therapy in HBV/HDV coinfected patients are currently applied, yet treatment response is low.

OBJECTIVES

We aimed to determine the efficacy of IFN α-2b therapy in patients with HBV/HDV coinfection.

PATIENTS AND METHODS

In this cross sectional study, 20 HBsAg carriers with positive Anti-HDVAb and RT-PCR for HDV RNA were recruited and treated for three year duration with 5 million units (MU) of IFN α-2b, three times weekly or one year with 5 MU of IFN α-2b daily. Sustained virological response (SVR) was defined as a negative qualitative HDV RT-PCR, 6 months after treatment cessation.

RESULTS

Overall, 3 (15%) subjects achieved SVR, 10 cases (50%) relapsed after treatment cessation and 7 (35%) patients did not clear HDV during the treatment.

CONCLUSIONS

HDV coinfection with HBV had very low response rate to high doses and long durations of IFN α-2b therapy.

Hepatitis delta virus: a peculiar virus

The hepatitis delta virus (HDV) is distributed worldwide and related to the most severe form of viral hepatitis. HDV is a satellite RNA virus dependent on hepatitis B surface antigens to assemble its envelope and thus form new virions and propagate infection. HDV has a small 1.7 Kb genome making it the smallest known human virus. This deceivingly simple virus has unique biological features and many aspects of its life cycle remain elusive. The present review endeavors to gather the available information on HDV epidemiology and clinical features as well as HDV biology.

Treatment of HBeAg positive chronic hepatitis B: interferon or nucleoside analogues

Interferon alpha has restricted efficacy in as much as only a proportion of patients show a response. However, in appropriately selected HBeAg-positive and HBeAg-negative patients, sustained suppression of viral replication can be achieved, and HBeAg or even HBsAg seroconversion can be attained. Thus, finite course of interferon alpha can be successful, and offer an advantage to patient. Interferon (IFN) remains a benchmark therapy for chronic hepatitis B. The main advantages of IFN-α over nucleoside analogues are the absence of resistance and the possibility of immune-mediated clearance of hepatitis B. Unfortunately, side effects preclude the use of interferon alpha in substantial proportions of patients, and prolonged maintenance therapy to suppress hepatitis B virus (HBV) is not feasible. Nucleoside analogues are given by mouth, once per day, and the safety, potency and efficacy have improved and facilitated treatment. However, maintenance of long-term suppression is required for the majority of patients. In general, treatment of chronic hepatitis B should target patients with active disease and viral replication, preferably before the signs and symptoms of cirrhosis or significant injury has occurred. Current EASL guidelines suggest that treatment be based on the evaluation of three criteria: Serum aminotransferase levels, serum HBV DNA levels and histological grade and stage. Many questions remain unanswered on the optimal treatment of patients with chronic hepatitis B with a nucleoside vs interferon alpha. Both forms of treatment have benefits and the choice should be selected and tailored. Stopping or futility rules can be implemented in patients who fail interferon. Recent data suggest the safety and efficacy of nucleoside analogues in the third trimester of pregnancy to reduce the risk of transmission from mothers to their children.

Nuclear export signal-interacting protein forms complexes with lamin A/C-Nups to mediate the CRM1-independent nuclear export of large hepatitis delta antigen

Nuclear export is an important process that not only regulates the functions of cellular factors but also facilitates the assembly of viral nucleoprotein complexes. Chromosome region maintenance 1 (CRM1) that mediates the transport of proteins bearing the classical leucine-rich nuclear export signal (NES) is the best-characterized nuclear export receptor. Recently, several CRM1-independent nuclear export pathways were also identified. The nuclear export of the large form of hepatitis delta antigen (HDAg-L), a nucleocapsid protein of hepatitis delta virus (HDV), which contains a CRM1-independent proline-rich NES, is mediated by the host NES-interacting protein (NESI). The mechanism of the NESI protein in mediating nuclear export is still unknown. In this study, NESI was characterized as a highly glycosylated membrane protein. It interacted and colocalized well in the nuclear envelope with lamin A/C and nucleoporins. Importantly, HDAg-L could be coimmunoprecipitated with lamin A/C and nucleoporins. In addition, binding of the cargo HDAg-L to the C terminus of NESI was detected for the wild-type protein but not for the nuclear export-defective HDAg-L carrying a P205A mutation [HDAg-L(P205A)]. Knockdown of lamin A/C effectively reduced the nuclear export of HDAg-L and the assembly of HDV. These data indicate that by forming complexes with lamin A/C and nucleoporins, NESI facilitates the CRM1-independent nuclear export of HDAg-L.

Prevalence, risk factors, and molecular epidemiology of hepatitis B and hepatitis delta virus in pregnant women and in patients in Mauritania

No recent data are available on hepatitis B virus (HBV) and hepatitis Delta virus (HDV) prevalence in Mauritania. One thousand twenty pregnant women and 946 patients visiting for routine checkups were screened for HBV and HDV infection. Demographic, epidemiological, ethnic, clinical, and biological data were recorded. HBV and HDV genotypes were determined by sequencing and phylogenetic analyses. In the pregnant women and patients cohorts, respectively, the prevalence of HBsAg (10.7% and 18.3%) and anti-HBcAb (66.3% and 76.5%) indicated high HBV endemicity. In pregnant women, exposure to HBV was significantly associated in multivariate analysis with education level, ethnicity, blood transfusion, and occupation. HDV antibodies (HDVAb) were found in 14.7% of pregnant women. In patients, HBsAg was found less frequently in females than in males. Again in multivariate analysis, exposure to HBV was significantly correlated with gender (males), and HDVAb positivity with age and gender. The HBV DNA viral load was >3 log IU/ml in only 10.1% of pregnant women and in 17.3% of patients. HDV-RNA was detectable in 21 (67.7%) of the 31 patients positive for HDVAb, and in 11 of the 16 pregnant women positive for HDVAb (68.8%). The most frequent HBV genotypes were: HBV/D, 53%; HBV/E, 35%; and HBV/A, 12%. Sub-genotyping revealed HBV/D1,/D7, and the recently described/D8. HDV genotypes were: HDV-1, 90.3% and HDV-5, 9.7%. This study confirms the high prevalence of HBV and HDV infections in Mauritania and demonstrates the high genetic diversity of HBV in this country.

KASL Clinical Practice Guidelines: Management of chronic hepatitis B

The guideline on the management of chronic hepatitis B (CHB) was first developed in 2004 and revised in 2007 by the Korean Association for the Study of the Liver (KASL). Since then there have been many developments, including the introduction of new antiviral agents and the publications of many novel research results from both Korea and other countries. In particular, a large amount of knowledge on antiviral resistance--which is a serious issue in Korea--has accumulated, which has led to new strategies being suggested. This prompted the new guideline discussed herein to be developed based on recent evidence and expert opinion.

TARGET POPULATION

The main targets of this guideline comprise patients who are newly diagnosed with CHB and those who are followed or treated for known CHB. This guideline is also intended to provide guidance for the management of patients under the following special circumstances: malignancy, transplantation, dialysis, coinfection with other viruses, pregnancy, and children.

Asian-Pacific consensus statement on the management of chronic hepatitis B: a 2012 update

Large volume of new data on the natural history and treatment of chronic hepatitis B virus (HBV) infection have become available since 2008. These include further studies in asymptomatic subjects with chronic HBV infection and community-based cohorts, the role of HBV genotype/naturally occurring HBV mutations, the application of non-invasive assessment of hepatic fibrosis and quantitation of HBV surface antigen and new drug or new strategies towards more effective therapy. To update HBV management guidelines, relevant new data were reviewed and assessed by experts from the region, and the significance of the reported findings was discussed and debated. The earlier "Asian-Pacific consensus statement on the management of chronic hepatitis B" was revised accordingly. The key terms used in the statement were also defined. The new guidelines include general management, indications for fibrosis assessment, time to start or stop drug therapy, choice of drug to initiate therapy, when and how to monitor the patients during and after stopping drug therapy. Recommendations on the therapy of patients in special circumstances, including women in childbearing age, patients with antiviral drug resistance, concurrent viral infection, hepatic decompensation, patients receiving immune suppression or chemotherapy and patients in the setting of liver transplantation and hepatocellular carcinoma, are also included.

Interferon alpha for chronic hepatitis D

BACKGROUND

Hepatitis D virus is a small defective RNA virus that requires the presence of hepatitis B virus infection to infect a person. Hepatitis D is a difficult-to-treat infection. Several clinical trials have been published on the efficacy of interferon alpha for hepatitis D virus (HDV) infection. However, there are few randomised trials evaluating the effects of interferon alpha, and it is difficult to judge any benefit of this intervention from the individual trials.

OBJECTIVES

To evaluate the beneficial and harmful effects of interferon alpha for patients with chronic hepatitis D.

SEARCH METHODS

We identified relevant for the review randomised clinical trials by electronic searches in the Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and Science Citation Index Expanded until May 2011. We also checked the bibliographic references of identified randomised trials, textbooks, and review articles in order to find randomised trials not identified by the electronic searches.

SELECTION CRITERIA

Randomised clinical trials evaluating interferon alpha versus placebo or no intervention for patients with chronic hepatitis D infection.

DATA COLLECTION AND ANALYSIS

Two authors assessed the trials and extracted data on mortality, virologic, biochemical, and histological response as well as adverse events at end of treatment and six months or more after completing treatment. The analyses were performed using the intention-to-treat principle including all randomised participants irrespective of follow-up. Drop-outs, withdrawals, and non-compliance were considered as treatment failures. Data were analysed with fixed- and random-effects models. Reported results were based on fixed-effect model except in cases where statistical significance varied between the two models.

MAIN RESULTS

Six randomised trials fulfilled the inclusion criteria. Two hundred and one randomised participants (male = 174) were included. The risk of bias in all the included trials was high. Five trials compared interferon alpha with no treatment in the control group. One of these trials had two treatment arms with a higher dose and lower dose of interferon alpha and a no-treatment control group. We analysed both treatment regimens as a single group in a primary analysis and as separate groups in the subgroup analysis of different interferon dosages. The sixth trial compared only a higher dose of interferon alpha with a lower dose.Meta-analysis of five trials comparing interferon alpha with no-treatment control group included 169 participants. There were seven drop-outs in the treatment group and nine in the control group. One patient out of 92 (1.1%) died in the interferon alpha group compared with zero out of 77 (0.0%) in the no-intervention control group (risk ratio (RR)) 3.00; 95% confidence interval (CI) 0.14 to 66.5). Interferon alpha led to failure of end of treatment virological response in 62/92 (67.4%) of the patients compared with 71/77 (92.2%) in the untreated controls (RR 0.76, 95% CI 0.66 to 0.87, P = 0.0001 by fixed-effect model and RR 0.71, 95% CI 0.43 to 1.16, P = 0.17 by random-effects model). Failure of normalisation of alanine aminotransferase (ALT) at the end of treatment was seen in 60/92 (65.2%) patients treated with interferon alpha versus 76/77 (98.7%) in the control group (RR 0.69, 95% CI 0.59 to 0.80, P < 0.00001). Sustained virological response was not achieved in 76/92 (82.6%) of patients on interferon compared with 73/77 (94.8%) of controls (RR 0.89, 95% CI 0.80 to 0.98, P = 0.02). Serum alanine aminotransferase was abnormal in 81/92 (88.0%) treated with interferon alpha patients at six months post-treatment follow-up compared with 76/77 (98.7%) in controls (RR 0.92, 95% CI 0.84 to 0.99, P = 0.04). There was no significant histological improvement in 67/92 (72.8%) patients treated with interferon alpha compared with 65/77 (84.4%) in controls (RR 0.86, 95% CI 0.74 to 1.00, P = 0.06).Two trials comparing a higher dose of interferon alpha with the lower dose showed no significant difference in sustained virological response (76.7% compared with 90.0%) (RR 0.85, 95% CI 0.68 to 1.07, P = 0.16). Adverse events such as flu-like symptoms, asthenia, weight loss, alopecia, thrombocytopenia, and leukopenia were reported in all these trials and the adverse events were related to interferon alpha. These were common and sometimes severe. One patient in the treatment group was reported to have died by suicide towards the end of the study period.

AUTHORS' CONCLUSIONS

Interferon alpha does not seem to cure hepatitis D in most patients. The agent seems effective in suppressing viral and liver disease activity in some patients, but this improvement is not sustained in the majority of patients. We cannot exclude overestimation of benefits and underestimation of harms due to high risk of bias (systematic errors) and high risk play of chance (random errors). Therefore, more randomised trials with large sample sizes and less risk of bias are needed before interferon can be recommended or refuted.

Peginterferon plus adefovir versus either drug alone for hepatitis delta

BACKGROUND

Chronic infection with hepatitis B virus and hepatitis delta virus (HDV) results in the most severe form of viral hepatitis. There is no currently approved treatment. We investigated the safety and efficacy of 48 weeks of treatment with peginterferon alfa-2a plus adefovir dipivoxil, peginterferon alfa-2a alone, and adefovir dipivoxil alone.

METHODS

We conducted a randomized trial in which 31 patients with HDV infection received treatment with 180 μg of peginterferon alfa-2a weekly plus 10 mg of adefovir daily, 29 received 180 μg of peginterferon alfa-2a weekly plus placebo, and 30 received 10 mg of adefovir alone weekly for 48 weeks. Follow-up was conducted for an additional 24 weeks. Efficacy end points included clearance of HDV RNA, normalization of alanine aminotransferase levels, and a decline in levels of hepatitis B surface antigen (HBsAg).

RESULTS

The primary end point--normalization of alanine aminotransferase levels and clearance of HDV RNA at week 48--was achieved in two patients in the group receiving peginterferon alfa-2a plus adefovir and two patients in the group receiving peginterferon alfa-2a plus placebo but in none of the patients in the group receiving adefovir alone. At week 48, the test for HDV RNA was negative in 23% of patients in the first group, 24% of patients in the second, and none of those in the third (P = 0.006 for the comparison of the first and third groups; P = 0.004 for the comparison of the second and third). The efficacy of peginterferon alfa-2a was sustained for 24 weeks after treatment, with 28% of the patients receiving peginterferon alfa-2a plus adefovir or peginterferon alfa-2a alone having negative results on HDV-RNA tests; none of the patients receiving adefovir alone had negative results. A decline in HBsAg levels of more than 1 log(10) IU per milliliter from baseline to week 48 was observed in 10 patients in the first group, 2 in the second, and none in the third (P<0.001 for the comparison of the first and third groups and P = 0.01 for the comparison of the first and second).

CONCLUSIONS

Treatment with peginterferon alfa-2a for 48 weeks, with or without adefovir, resulted in sustained HDV RNA clearance in about one quarter of patients with HDV infection. (Current Controlled Trials number, ISRCTN83587695.).

Replicative and transcriptional activities of hepatitis B virus in patients coinfected with hepatitis B and hepatitis delta viruses

Hepatitis B virus (HBV) and hepatitis delta virus (HDV) interplay was investigated by examining liver and serum samples from 21 coinfected and 22 HBV-monoinfected patients with chronic liver disease. Different real-time PCR assays were applied to evaluate intrahepatic amounts of HBV DNA, covalently closed circular DNA (cccDNA), pregenomic RNA (pgRNA), pre-S/S RNAs, and HDV RNA. Besides HBV DNA and HDV RNA levels, HBsAg concentrations in the sera were also determined. HDV-coinfected cases showed significantly lower median levels of serum HBV DNA (-5 log), intrahepatic relaxed-circular DNA (-2 log), and cccDNA (-2 log) than those of HBV-monoinfected cases. Interestingly, pgRNA and pre-S/S RNA amounts were significantly lower (both -1 log) in HDV-positive patients, whereas serum HBsAg concentrations were comparable between the two patient groups. Pre-S/S RNA and HBsAg amounts per cccDNA molecule were higher in HDV-positive patients (3-fold and 1 log, respectively), showing that HBV replication was reduced, whereas synthesis of envelope proteins was not specifically decreased. The ratios of cccDNA to intracellular total HBV DNA showed a larger proportion of cccDNA molecules in HDV-positive cases. For these patients, both intrahepatic and serum HDV RNA amounts were associated with cccDNA but not with HBsAg or HBV DNA levels. Finally, HBV genomes with large deletions in the basal core promoter/precore region were detected in 5/21 HDV-positive patients but in no HDV-negative patients and were associated with lower viremia levels. These findings provide significant information about the interference exerted by HDV on HBV replication and transcription activities in the human liver.

European guideline for the management of hepatitis B and C virus infections, 2010

These are the guidelines on hepatitis B and C management for IUSTI/WHO in Europe, 2010. They describe the epidemiology, diagnosis, clinical features, treatment and prevention of hepatitis B and C with particular reference to sexual health clinical practice.

[Characteristics of hepatitis and influenza antivirals: update 2009]

This article aims to review hepatitis B and C and influenza infections and to summarise the main characteristics of the antiviral drugs available to treat those infections in adults. The review of each drug focuses on dosage depending on treatment indication, dosage adjustment in renal or hepatic impairment, main pharmacokinetic features and the most significant adverse effects and drug interactions.

Clathrin-mediated post-Golgi membrane trafficking in the morphogenesis of hepatitis delta virus

Clathrin is involved in the endocytosis and exocytosis of cellular proteins and the process of virus infection. We have previously demonstrated that large hepatitis delta antigen (HDAg-L) functions as a clathrin adaptor, but the detailed mechanisms of clathrin involvement in the morphogenesis of hepatitis delta virus (HDV) are not clear. In this study, we found that clathrin heavy chain (CHC) is a key determinant in the morphogenesis of HDV. HDAg-L with a single amino acid substitution at the clathrin box retained nuclear export activity but failed to interact with CHC and to assemble into virus-like particles. Downregulation of CHC function by a dominant-negative mutant or by short hairpin RNA reduced the efficiency of HDV assembly, but not the secretion of hepatitis B virus subviral particles. In addition, the coexistence of a cell-permeable peptide derived from the C terminus of HDAg-L significantly interfered with the intracellular transport of HDAg-L. HDAg-L, small HBsAg, and CHC were found to colocalize with the trans-Golgi network and were highly enriched on clathrin-coated vesicles. Furthermore, genotype II HDV, which assembles less efficiently than genotype I HDV does, has a putative clathrin box in its HDAg-L but interacted only weakly with CHC. The assembly efficiency of the various HDV genotypes correlates well with the CHC-binding activity of their HDAg-Ls and coincides with the severity of disease outcome. Thus, the clathrin box and the nuclear export signal at the C terminus of HDAg-L are potential new molecular targets for HDV therapy.

[Sexually transmissible hepatitis viruses]

The transmission of hepatitis viruses as a result of sexual activity is a common problem in medical practice. A system of stages is proposed to diagnose viral hepatitis. Testing for anti-HBc, HBsAg, anti-HAV and anti-HCV is sufficient for initial screening. Depending on the circumstances, this may be followed by further tests for HBV, HCV and HAV. If initial screening provides no evidence, further tests for HEV, Epstein-Barr virus, cytomegalovirus or other agents are conducted.

Asian-Pacific consensus statement on the management of chronic hepatitis B: a 2008 update

Large amounts of new data on the natural history and treatment of chronic hepatitis B virus (HBV) infection have become available since 2005. These include long-term follow-up studies in large community-based cohorts or asymptomatic subjects with chronic HBV infection, further studies on the role of HBV genotype/naturally occurring HBV mutations, treatment of drug resistance and new therapies. In addition, Pegylated interferon alpha2a, entecavir and telbivudine have been approved globally. To update HBV management guidelines, relevant new data were reviewed and assessed by experts from the region, and the significance of the reported findings were discussed and debated. The earlier "Asian-Pacific consensus statement on the management of chronic hepatitis B" was revised accordingly. The key terms used in the statement were also defined. The new guidelines include general management, special indications for liver biopsy in patients with persistently normal alanine aminotransferase, time to start or stop drug therapy, choice of drug to initiate therapy, when and how to monitor the patients during and after stopping drug therapy. Recommendations on the therapy of patients in special circumstances, including women in childbearing age, patients with antiviral drug resistance, concurrent viral infection, hepatic decompensation, patients receiving immune-suppressive medications or chemotherapy and patients in the setting of liver transplantation, are also included.

Asian-Pacific consensus statement on the management of chronic hepatitis B: a 2008 update

Large amounts of new data on the natural history and treatment of chronic hepatitis B virus (HBV) infection have become available since 2005. These include long-term follow-up studies in large community-based cohorts or asymptomatic subjects with chronic HBV infection, further studies on the role of HBV genotype/naturally occurring HBV mutations, treatment of drug resistance and new therapies. In addition, Pegylated interferon alpha2a, entecavir and telbivudine have been approved globally. To update HBV management guidelines, relevant new data were reviewed and assessed by experts from the region, and the significance of the reported findings were discussed and debated. The earlier "Asian-Pacific consensus statement on the management of chronic hepatitis B" was revised accordingly. The key terms used in the statement were also defined. The new guidelines include general management, special indications for liver biopsy in patients with persistently normal alanine aminotransferase, time to start or stop drug therapy, choice of drug to initiate therapy, when and how to monitor the patients during and after stopping drug therapy. Recommendations on the therapy of patients in special circumstances, including women in childbearing age, patients with antiviral drug resistance, concurrent viral infection, hepatic decompensation, patients receiving immune-suppressive medications or chemotherapy and patients in the setting of liver transplantation, are also included.