A treatment algorithm for the management of chronic hepatitis B virus infection in the United States: 2008 update

[A 23-year-old asymptomatic HBsAg positive woman]

This paper discusses the case of a young 23-year-old asymptomatic HBsAg woman, diagnosed in the immune-tolerance phase of HBV infection. The monitoring shows the loss of tolerance and eventually the transition to the inactive carrier state. Management strategies are discussed for each phase according to the recent EASL guidelines.

The role of quantitative hepatitis B serology in the natural history and management of chronic hepatitis B

Chronic hepatitis B (CHB) remains a serious clinical problem worldwide. Advances in molecular technology have enabled the development of sensitive assays for the detection and quantification of hepatitis B virus (HBV) nucleic acid and demonstrated a positive correlation between serum HBV DNA levels and disease progression. Assessment of specific serologic and virologic factors also plays a pivotal role in the diagnosis and effective management of individuals with CHB. Recent development of quantitative assays for intrahepatic HBV replicative intermediates, as well as hepatitis B e antigen and hepatitis B surface antigen, has spurred investigation into the relationship between these factors and response to antiviral therapy and disease progression. Recent findings from preclinical and clinical investigations indicate that these factors may have promise in identifying patients likely to respond to treatment. Additional work is needed to standardize and validate these assays before they can be considered to be of true diagnostic value. Further evaluation is needed to decide which will have the greatest clinical applicability.

Renal dysfunction in chronic hepatitis B patients treated with adefovir dipivoxil

Renal dysfunction has been reported in patients treated with adefovir dipivoxil (ADV); however, its incidence and clinical importance may be underappreciated given the lack of long-term follow-up and data outside of a clinical trial setting. Our goal was to examine the severity and incidence of renal dysfunction in a real-life setting for patients treated with ADV and whose baseline estimated glomerular filtration rate (eGFR) was >50 mL/minute. We performed a cohort study of 290 chronic hepatitis B patients: 145 patients treated with 10 mg ADV and 145 patients unexposed to ADV at two community clinics, who were matched for age (+/-10 years), sex, and baseline eGFR. The exposed and unexposed populations were well-matched with a similar mean age (46-47 years), proportion of male patients (76.5%), baseline serum creatinine (0.97-0.99 mg/dL), and baseline creatinine clearance (85.0-85.4 mL/minute). The incidence density for renal dysfunction defined by treatment termination and/or development of eGFR < or =50 mL/minute was five cases per 100 patient-years in the exposed group compared with 1.36 cases per 100 patient-years in the unexposed group (P = 0.02). The relative risk of exposed to unexposed was 3.68 (95% confidence interval 1.1-19.3). On Cox proportional hazard analysis also inclusive of sex, ADV was a significant predictor of significant renal dysfunction (hazard ratio [HR] 3.94, P = 0.03). There were also significant trends for age >50 years (HR 3.49, P = 0.087), mild renal impairment at baseline (HR 4.49, P = 0.073), and hypertension and/or diabetes mellitus (HR 2.36, P = 0.074).

CONCLUSION

ADV is an independent predictor for significant deterioration of renal function. Patients on ADV should be monitored, especially patients who are older, have baseline renal insufficiency, or have hypertension and/or diabetes mellitus.

Chronic hepatitis B and C: update on therapy

Chronic infections with HBV and HCV are a major cause of liver-associated morbidity and mortality worldwide. An increased knowledge of HBV and HCV virology, natural history and predictors of virological response has led to the development of new strategies to improve treatment outcomes. The use of new antiviral agents with greater potency and a high genetic barrier to resistance, as well as on-treatment monitoring of virological response, may result in improved outcomes in HBV therapy. A greater understanding of predictors of virological response has led to the ability to individualize therapy in chronic HCV infection. Several new antiviral agents specifically targeting HCV are in development and should have a major impact on treatment response rates over the next few years.

Efficacy of consensus interferon in treatment of HbeAg-positive chronic hepatitis B: a multicentre, randomized controlled trial

Background

Consensus interferon (CIFN) is a newly developed type I interferon.

Aims

This multicentre, controlled trial was conducted to determine the efficacy of CIFN and to compare it with alpha-1b-interferon (IFN-α1b) in the treatment of patients with hepatitis B e antigen (HBeAg)-positive chronic hepatitis B.

Methods

144 Patients were randomly assigned to receive 9 μg CIFN (CIFN group) or 50 μg INF-α1b (IFN-alpha group) subcutaneously 3 times weekly for 24 weeks, followed by 24 weeks of observation. Efficacy was assessed by normalization of serum alanine transaminase (ALT) levels and the non-detectability of serum hepatitis B virus DNA or HBeAg at the end of treatment and 24 weeks after stopping treatment.

Results

There was no statistically significant difference in the serological, virological and biochemical parameters between CIFN and IFN-α1b groups at the end of the therapy and follow-up period (p > 0.05). Overall, at the end of treatment, 7.0% (5/71) and 35.2% (25/71) of patients in the CIFN group showed a complete or partial response compared with 7.4% (5/68) and 33.8% (23/68) of the IFN-alpha group (p = 0.10). At 24 weeks after stopping treatment, 6.9% (5/72) and 37.5% (27/72) of patients in the CIFN group showed complete response or partial response compared with 7.1% (5/70) and 34.3% (24/70) of the IFN-alpha group (p = 0.10).

Conclusion

These findings suggest that 9 μg CIFN is effective in the treatment of patients with HBeAg-positive chronic hepatitis B. It can gradually induce ALT normalization and HBV DNA clearance and HBeAg loss or HBeAg/HBeAb seroconversion.

Hepatitis B virus reactivation following allogeneic hematopoietic stem cell transplantation

Reactivation of resolved hepatitis B virus (HBV) infection has been reported in allogeneic hematopoetic stem cell transplantation (HSCT) recipients, but its epidemiology is not well characterized. We performed a retrospective assessment of the timing and risk factors of HBV reactivation among patients with resolved HBV infection undergoing allogeneic HSCT between January 2000 and March 2008. HBV reactivation was defined as development of positive hepatitis B surface antigen after transplant. Among the 61 patients with resolved HBV infection before transplant (hepatitis B core antibody-positive, hepatitis B surface antigen-negative), 12 (19.7%) developed HBV reactivation. The cumulative probability of HBV reactivation 1, 2, and 4 years after transplant was 9.0%, 21.7%, and 42.9%, respectively. In a time-dependent Cox model, the adjusted hazard ratio (HR) of HBV reactivation for patients with pretransplant hepatitis B surface antibody levels <10 milli-international units per milliliter (mIU/mL) was 4.56 (95% confidence interval [CI] 1.23-16.9) compared to those with levels > or =10 mIU/mL; the adjusted HR among patients who developed extensive chronic graft-versus-host disease (cGVHD) was 7.21 (95% CI 1.25-41.5) compared to those who did not. HBV reactivation is a common late complication among allogeneic HSCT recipients with pretransplant resolved infection. Screening for HBV reactivation should be considered for at-risk HSCT recipients. In this cohort, HBV reactivation often developed in patients with cGVHD. Liver biopsy was useful in those patients with both to delineate the contribution of each to liver dysfunction.

Patterns of managing chronic hepatitis B treatment-related drug resistance: a survey of physicians in Mainland China, South Korea, Taiwan, and Thailand

PURPOSE

The emergence of antiviral resistance can negate the benefits of antiviral therapy in patients with chronic hepatitis B (CHB). This study aimed to assess how physicians in Asia manage suspected antiviral resistance.

METHODS

Randomly selected CHB-treating physicians in Mainland China, South Korea, Taiwan, and Thailand underwent a face-to-face interview. A standardized questionnaire was used to assess how physicians identify, monitor, and manage suspected resistance and its associated medical costs.

RESULTS

We interviewed 575 physicians from January to May 2008. Most physicians preferred a "prevention-of-antiviral resistance" strategy over a "rescue-once-resistance-develops" strategy. Physicians had encountered lamivudine resistance most frequently (96-100% of respondents), followed by the resistance to adefovir (18-58%) and entecavir (3-7%). While physicians in South Korea and Taiwan have access to resistance testing, physicians in Mainland China and Thailand have limited access to resistance testing but rely on HBV DNA and alanine aminotransferase (ALT) tests to identify resistance. Once resistance is suspected, 60% of the physicians in Mainland China, South Korea, and Thailand monitored these patients quarterly and the remaining 40% opted for monthly follow-up. In comparison, 70% of the Taiwanese physicians monitored these patients monthly. The average total direct medical costs, excluding antiviral costs, to manage a patient during the first year after suspected resistance is identified ranged from USD $319 to USD $709.

CONCLUSIONS

Limited access to HBV resistance tests causes physicians in Asia to manage suspected resistance by various HBV DNA assays and ALT tests. This raises concerns that resistance may not be detected early enough to be rescued efficiently.

HBeAg seroconversion as an important end point in the treatment of chronic hepatitis B

During the natural history of chronic hepatitis B virus (HBV) infection, the loss of serum hepatitis B e antigen (HBeAg) and the development of anti-HBe antibodies (HBeAg seroconversion) mark a transition from the immune-active phase of disease to the inactive carrier state. This review examines the evidence from natural history and cohort studies on the relationship between HBeAg seroconversion and disease progression. The role of HBeAg seroconversion as an important milestone in the management of HBeAg-positive patients with chronic hepatitis B (CHB), as well as the advantages and disadvantages of administering a finite course of therapy for HBeAg-positive CHB, is also discussed. The evidence from natural history and cohort studies indicates that spontaneous or treatment-induced HBeAg seroconversion is associated with lower rates of disease progression to cirrhosis and hepatocellular carcinoma, a potential of hepatitis B surface antigen seroconversion, and improved survival rates. Updated guidelines developed by major liver associations recommend stopping oral therapy for HBeAg-positive patients who achieve sustained HBeAg seroconversion with polymerase chain reaction-undetectable HBV-DNA on two separate occasions for 6 or more months apart, taking into consideration the individual's clinical and virologic response to therapy, as well as the severity of liver disease. Thus, early induction of HBeAg seroconversion with interferon-based therapy or oral nucleos(t)ide analogues has important clinical and socioeconomic implications for the management of CHB.

Chronic hepatitis B: who to treat and which choice of treatment?

The goal of antiviral therapy in patients with chronic hepatitis B is to prevent, through persistent suppression of HBV replication, cirrhosis and hepatocellular carcinoma. Currently, seven drugs are available: IFN-alpha, pegylated interferon, lamivudine, adefovir dipivoxil, entecavir, telbivudine and tenofovir. The choice of the drugs should always take into consideration the clinical features of patients, the antiviral efficacy of each drug, the risk of developing resistance, the long-term safety profile, the method of administration and the cost of therapy. Ideal candidates for treatment are hepatitis B e antigen-positive patients with a prolonged phase of immune clearance and hepatitis B e antigen-negative patients with elevated levels of serum HBV DNA, abnormal alanine aminotransferase and histologic evidence of moderate or severe liver necroinflammation and/or fibrosis. Patients with compensated or decompensated cirrhosis should be treated, even if alanine aminotransferase levels are normal and/or serum HBV DNA levels are low, in order to prevent disease flare and to improve liver function.

Effect of prophylactic lamivudine for chemotherapy-associated hepatitis B reactivation in lymphoma: a meta-analysis of published clinical trials and a decision tree addressing prolonged prophylaxis and maintenance

Lamivudine prophylaxis is an effective strategy in HbSAg-positive patients receiving cancer chemotherapy. Recent data indicate that a lamividune-prophylaxis strategy results in a decrease of hepatitis B virus (HBV) reactivation rates, though its effect on HBV-mortality remains equivocal. This report evaluates the benefits from this strategy among lymphoma patients and develops a management approach for patients with prolonged immunosuppression. A Medline search was conducted to retrieve published trials on HBsAg-positive lymphoma patients receiving prophylactic lamivudine during chemotherapy. Basic inclusion criterion was to report HBV-reactivation rates with and without lamivudine prophylaxis. A meta-analysis of the risk of HBV-reactivation and HBV-related mortality was conducted, and the pooled effect was calculated as risk ratio (RR). We found that lamivudine prophylaxis is associated with a significant reduction in hepatitis B virus reactivation (RR 0.21, 95%CI 0.13-0.35) and a trend in reducing HBV-related mortality (RR 0.68, 95%CI 0.19-2.49). In order to study the long-term effects of anti-HBV prophylaxis when prolonged immunosuppression is needed, we used our findings to model a decision tree. Overall survival was the main outcome used in the analysis. Rituximab maintenance in B-cell lymphomas was used as a paradigm of prolonged immunosuppression. We found that extended anti-HBV prophylaxis can improve survival rates by 2.4% in HBsAg-positive patients. If 1,000 HBsAg-positive lymphoma patients receive prophylaxis, one will die from hepatitis B virus reactivation versus 25/1,000 if no prophylaxis is administered. This effect is probably mediated through a reduction of hepatitis B virus reactivation and HBV-related mortality. The ideal antiviral agent needs to be determined.

Special populations with hepatitis B virus infection

Treatment of patients with chronic hepatitis B virus (HBV) infection who have advanced disease or comorbidities can be challenging, and recommendations may differ from standard guidelines. Among the special populations that merit specific consideration are patients with compensated or decompensated cirrhosis, organ transplantation, acute hepatitis B, pregnancy, coinfection with hepatitis C and/or D virus, chronic renal failure, and children. Major advances have been made in management of many of these special populations because of recent increasing availability of oral nucleosides, which are generally well tolerated and highly effective despite presence of other morbidities or viral infections. Also important have been changes in the management of hepatitis B during the peri-liver transplantation period that allows for prevention of reinfection in the majority of cases. However, much remains to be done to determine which patients should be treated and which should be monitored on no specific therapy. Outcomes of chronic HBV infection in persons with coinfection and in children have varied from different areas of the world, but it is not clear whether these differences are due to host and racial differences or to viral genotypic differences. Further studies are particularly needed in assessing the safety and efficacy of therapy in pregnant women, in children, and in patients with hepatitis D and C virus coinfection.

Benefits and risks of combination therapy for hepatitis B

In successful antiviral therapy of hepatitis B, drug combinations, particularly combinations without cross-resistance, can delay or prevent the emergence of drug-resistant mutants. Because drug-resistant mutants are archived and may limit future therapeutic options, prevention is important for long-term therapeutic efficacy. Additionally, combining drugs may achieve synergistic or additive antiviral effects compared with single drug therapy. Undesirable aspects of combination therapy include higher treatment costs and possibly lower adherence rates (due to pill number or complexity of regimen). Potentially harmful effects of combination therapy include higher rates of side effects, reduced efficacy due to drug competition, and the risk of multidrug-resistant hepatitis B virus (HBV) if combination therapy is insufficient to prevent resistance. Combination therapy has been shown to reduce the rate of drug resistance in chronic hepatitis B, but only when drugs with a low barrier to resistance are used (lamivudine, adefovir). Combination therapies may achieve greater degrees of HBV DNA suppression, but this has not been associated with higher rates of seroconversion (hepatitis B e antigen or hepatitis B surface antigen) compared to single drug therapy. The benefit of combination therapy has yet to be demonstrated with agents that are associated with a high barrier to resistance (tenofovir, entecavir). The use of combination therapy is recommended in specific patient groups: those with decompensated cirrhosis, those coinfected with human immunodeficiency virus and HBV who are on antiretroviral therapy, those who have undergone liver transplantation, and those with drug-resistant HBV infection. There is insufficient evidence to recommend combination therapy as first-line therapy for all patients with chronic hepatitis B.

Hepatitis B and human immunodeficiency virus coinfection

Coinfection with human immunodeficiency virus-1 (HIV) and hepatitis B virus (HBV) is common; worldwide, an estimated 10% of HIV-infected persons have chronic hepatitis B. Because the incidence of traditional acquired immunodeficiency syndrome-related opportunistic infections has decreased with successful anti-HIV therapy, liver disease has emerged as a leading cause of morbidity and mortality in HIV-infected individuals. HIV infection negatively impacts all phases of the natural history of hepatitis B leading to increased rates of persistent infection, higher HBV DNA levels, lower rates of hepatitis B e antigen loss, increased cirrhosis and liver-related mortality, and increased risk of hepatocellular carcinoma at lower CD4+ T cell counts. The management of hepatitis B in HIV infection is complicated by the dual activity of several nucleoside analogs, the more rapid development of lamivudine-resistant HBV in patients who are HIV-positive, and the paucity of studies in this population. Until further research emerges on the optimal treatment for this population, data from HBV monoinfected persons will need to be extrapolated to the HIV-HBV coinfected population. Further research is also needed to determine the mechanism(s) for the increased liver disease progression and optimal treatment goals.

Antiviral resistance and hepatitis B therapy

The management of chronic hepatitis B currently rests with long-term therapy using oral nucleoside analogs. The major limitation of long-term therapy is antiviral resistance. Antiviral resistance is due to the high rate of mutations that can occur during hepatitis B virus (HBV) replication and the selection of these mutants due to a replication advantage in the presence of the antiviral agent. Indeed, high rates of antiviral resistance have been found with long-term use of lamivudine, in up to 76% of patients treated for 5 years or more. Rates of antiviral resistance are lower with adefovir therapy, approximately 30% at 5 years. Newer more potent nucleoside analogs (tenofovir and entecavir) have proven to have much lower rates of antiviral resistance (<1% after 2 years in treatment-naïve subjects), but the long-term rates of resistance have yet to be fully defined. The appearance of these viral mutations (genotypic resistance) is usually followed by rises in HBV DNA levels (virological breakthrough) and then by rises in serum aminotransferase levels (biochemical breakthrough). The appearance of antiviral resistance can be accompanied by a transient but occasionally severe exacerbation of the underlying liver disease which in some instances has led to acute liver failure. Combinations of nucleoside analogs may offer an approach to preventing antiviral resistance, but the efficacy and safety of this approach have yet to be shown. A future research priority is to identify new agents active against HBV that target different steps in the viral life-cycle and might provide effective means to circumvent the antiviral resistance of nucleoside analogs.

Pirfenidone inhibits carbon tetrachloride- and albumin complex-induced liver fibrosis in rodents by preventing activation of hepatic stellate cells

1. Pirfenidone (PFD; 5-methyl-1-phenyl-2(1H)-pyridone) is an effective and novel agent with antifibrotic and anti-inflammatory properties. In the present study, we investigated the antifibrotic effects of PFD on experimental liver fibrosis models in rodents and the possible underlying molecular mechanisms. 2. Liver fibrosis was induced by carbon tetrachloride (CCl(4)) in BALB/c mice. Pirfenidone (250 mg/kg) and silymarin (50 mg/kg) were given to different groups of rats by gastric gavage for 4 weeks. Pirfenidone significantly attenuated fibrosis severity, as determined by histopathological scores and hydroxyproline levels in liver tissue, by 49.8 and 44.9%, respectively, compared with the CCl(4)-treated group. The antifibrotic effects of PFD were significantly greater than those of silymarin, as indicated by a decrease of 23.5 and 24.8% in histopathological scores and hydroxyproline levels, respectively. 3. Liver fibrosis was also induced by albumin antigen-antibody complex in Wistar rats, which were then treated with the same doses of PFD and silymarin for 8 weeks. Pirfenidone significantly reduced the degree of fibrosis compared with CCl(4)-treated rats (by 45.0 and 51.0% as determined by histopathological scores and hydroxyproline levels in liver tissue, respectively). The antifibrotic effects of PFD were comparable to those of silymarin. 4. The effects of PFD on the expression of extracellular matrix-associated genes in human hepatic stellate cells (the LX-2 cell line) were measured by real-time quantitative polymerase chain reaction. LX-2 cells were treated with or without 100 micromol/L or 1 mmol/L PFD for 24 h. Pirfenidone significantly inhibited the expression of a-smooth muscle actin and Type I collagen in 8 ng/mL transforming growth factor-beta1- or 5% fetal bovine serum-activated LX-2 cells in a dose-dependent manner. 5. In conclusion, the results of the present study demonstrate that PFD is effective in ameliorating fibrogenesis induced by CCl(4) in mice and by the albumin complex in rats. These effects were mediated mainly via inhibition of the activation of hepatic stellate cells, as well as antifibrotic actions (i.e. inhibition of collagen synthesis) of PFD.

Chronic hepatitis B: early viral suppression and long-term outcomes of therapy with oral nucleos(t)ides

Chronic hepatitis B is a serious health problem worldwide with a substantial minority of patients experiencing premature death due to end-stage liver disease and/or hepatocellular carcinoma. Antiviral therapy may help prevent complications of chronic hepatitis B, and seven agents are currently approved in many countries. Of these agents, five are nucleos(t)ide analogs that all have a risk of antiviral drug resistance with long-term use. Efforts have been made in the recent years to prevent or to reduce the risk of viral resistance in patients treated with oral nucleos(t)ides as the majority of these patients will require therapy for 3-5 years or longer. One approach is to identify patients who would most likely develop antiviral resistance on long-term therapy using predictors obtainable early in the course of treatment, when intervention with new or additional therapy can be instituted. The most important predictors of treatment outcomes are serum HBV DNA levels at baseline and during the first 6 months of therapy. The purpose of this synopsis is to review the recent literature regarding the importance of serum HBV DNA levels in association with treatment outcomes in chronic hepatitis B, particularly the association of complete viral suppression early in the course of oral therapy with long-term treatment outcomes, particularly the incidence of antiviral drug resistance.

Telbivudine in the treatment of chronic hepatitis B

INTRODUCTION

The treatment of chronic hepatitis B virus (HBV) infection has been revolutionized in the past decade by the increased availability of effective antiviral agents. Telbivudine is an L-nucleoside that is structurally related to lamivudine and has recently been approved for use in patients with chronic HBV infection. Telbivudine is highly selective for HBV DNA and inhibits viral DNA synthesis with no effect on human DNA or other viruses. This article reviews the pharmacology, pharmacokinetics, therapeutic efficacy and safety of telbivudine, and discusses its place in the current armamentarium against HBV.

METHODS

Relevant publications were identified from searches of Medline and PubMed between 2000 and 2008, using the search terms "hepatitis B/HBV," "telbivudine/LdT," "beta-L-thymidine," "pharmacokinetics," "safety," "adverse events," and "resistance." The reference lists of retrieved articles were searched for relevant studies.

RESULTS

Phase 3 clinical studies demonstrate that telbivudine is superior to lamivudine over a 2-year period in hepatitis B e-antigen (HBeAg)-positive and HBeAg-negative patients. Telbivudine was associated with a statistically significantly greater reduction in HBV DNA, greater proportion of alanine aminotransferase normalization, and greater histological response than lamivudine. Furthermore, telbivudine use resulted in fewer cases of treatment failure and less virological resistance than lamivudine. However, after 2 years of therapy, telbivudine resistance was appreciable (25%) and considerably higher than that seen with other new antivirals such as tenofovir and entecavir. Overall, telbivudine was found to be safe, although grade 3 or 4 adverse events, including elevations in creatine kinase, were more commonly found in patients receiving telbivudine than lamivudine. Telbivudine is not active against lamivudine-resistant HBV.

CONCLUSIONS

Telbivudine is a new antiviral agent joining the armamentarium against HBV. It is superior to lamivudine in terms of therapeutic response and resistance profile. However, concerns about resistance with long-term use, along with inferior cost-effective analyses, have relegated telbivudine to a second-line agent in the management of chronic HBV infection.

Hepatitis B therapy in children

Chronic hepatitis B virus (HBV) infection is a major cause of liver disease throughout the world, leading to cirrhosis and hepatocellular carcinoma in many individuals. Children are more likely to develop chronic HBV infection as they demonstrate greater immunotolerance to the virus, and response to therapy in children remains disappointing. Three therapeutic agents for chronic HBV infection in children have been approved in the USA, including standard IFN-alpha, lamivudine and adefovir. IFN-alpha has been the most effective ( approximately 30% hepatitis B e antigen [HBeAg] seroconversion; 10% hepatitis B surface antigen [HBsAg] seroconversion), although benefits are primarily observed in children with alanine aminotransferase levels over two-times the upper limit of normal and must be weighed against significant side effects. Studies comparing the long-term outcome of chronic hepatitis B in children treated with IFN-alpha and in untreated controls show that the rate of anti-HBeAb seroconversion tends to overlap in treated and untreated patients within a few years of follow-up, suggesting that IFN-alpha simply accelerates a spontaneous event. Lamivudine's virologic response rates mirror those of IFN-alpha (23-31% HBeAg seroconversion) with easier administration and a better safety profile but lower HBsAg seroconversion (2-3%) and high rates of drug resistance. Adefovir data show low rates of resistance and a good safety profile, but virologic response was limited to adolescent patients and was lower than that of lamivudine (16% HBeAg seroconversion; <1% HBsAg seroconversion). Entecavir and tenofovir, both approved therapies for adults with chronic HBV infection, are in trials for use in children. Future therapies will probably include these agents as well as combined therapies. Finally, watchful waiting of children is an option since current therapies are only 30% effective at best, although the long-term impact of therapy in childhood on rates of cirrhosis and hepatocellular carcinoma remains unknown.

Treatment of HBeAg-positive patients with nucleos/tide analogues

The two main goals of hepatitis B therapy are durable viral suppression and avoidance of antiviral resistance. Recent treatment guidelines now recognize the importance of these treatment endpoints in the prevention of end-stage liver disease and hepatocellular carcinoma rather then other surrogate markers such as HBeAg seroconversion and serum alanine aminotransferase normalization, especially in patients who acquired hepatitis B virus infection early in life. A variety of therapeutic options are now available for the treatment of chronic hepatitis B infection, including four nucleos/tide analogues (i.e lamivudine, adefovir, entecavir and telbivudine), along with standard and pegylated interferon. Newer oral nucleos/tide analogues that include tenofovir, emtricitabine and clevudine are soon likely to be approved worldwide. Given the wide array of choices and the complex nature of chronic hepatitis B infection, selection of the appropriate therapeutic agent can be challenging for clinicians. Effective treatment decisions require an understanding of the natural history of hepatitis B and knowledge of its life cycle and molecular biology. This review includes the range of treatment options and criteria for determining when and how to most effectively intervene with antiviral therapy for chronically infected patients positive for the HBeAg.