Efficacy of hepatitis B vaccination and interferon-alpha-2b combination therapy versus interferon-alpha-2b monotherapy in children with chronic hepatitis B

Efficacy and safety of therapeutic vaccines for the treatment of chronic hepatitis B: A systematic review and meta-analysis of randomized controlled trials update

BACKGROUND

Most people diagnosed with chronic hepatitis B (CHB) need treatment to help reduce the risk of liver disease and limit disease transmission. Therapeutic vaccine (TV) candidates have been under study for their clinical effects on inducing HBV-specific host immune responses. This review aimed to systematically synthesize updated evidence on the efficacy and safety of TVs in patients with CHB.

METHODS

This systematic review was performed by searching different databases from January to February 2021. Completed randomized controlled trials that reported TVs' efficacy and/or safety for treating CHB compared with the standard of care (SOC) or placebo were included. Efficacy and safety estimates were reported as the logarithm of the odds ratio and risk differences, respectively. I2 > 50% was considered significant heterogeneity. Significant publication bias was considered when Egger's test P value < .10. The risk of bias was assessed using the Cochrane Risk of Bias tool. The GRADE methodology was used to assess the certainty of the evidence for each outcome.

RESULTS

Twenty-four articles with 2889 pooled samples were included. TVs made a significant difference in hepatitis B envelope antigen (HBeAg) SC (log OR = 0.76, P = .01) and (log OR = 0.40, P = .03) compared to placebo and combination therapy, respectively. HBeAg SC was significantly affected by TVs at the end of follow up (log OR = 0.49, P = .01), with significant HBsAg mean difference (MD = -0.62, P = .00). At the end of treatment, the TVs had no significant effect on HBV DNA negativity over the SOC (log OR = 0.62, P = .09) or placebo (log OR = -0.07, P = .91). TVs do not significantly affect the risk of serious adverse events (RD 0.02, 95% CI 0.00-0.04).

CONCLUSION

In patients with CHB, TVs had significant effects on HBeAg SC compared to the SOC or placebo. There was no significant difference between serious adverse events. TVs are promising treatment strategy to overcome CHB.

Exploring evidence-based innovative therapy for the treatment of chronic HBV infection: experimental and clinical

With the advent of various vaccines and antimicrobial agents during the 20th century, the control and containment of infectious diseases appeared to be a matter of time. However, studies unveiled the diverse natures of microbes, their lifestyle, and pathogenetic potentials. Since the ground-breaking discovery of the hepatitis B virus (HBV) by Baruch Blumberg and the subsequent development of a vaccine in the early 1980s, the main task of the scientific community has been to develop a proper management strategy for HBV-induced chronic liver diseases. In the early 1980’s, standard interferon (IFN) induced a reduction of HBV DNA levels, followed by the normalization of serum transaminases (alanine aminotransferase, ALT), in some chronic hepatitis B (CHB) patients. However, in the course of time, the limitations of standard IFN became evident, and the search for an alternative began. In the late 1980’s, nucleoside analogs entered the arena of CHB treatment as oral drugs with potent antiviral capacities. At the beginning of the 21st century, insights were developed into the scope and limitations of standard IFN, pegylated-IFN as well as nucleoside analogs for treating CHB. Considering the non-cytopathic nature of the HBV, the presence of covalently closed circular DNA (cccDNA) in the nucleus of the infected hepatocytes and HBV-induced immune-mediated liver damages, a new field of CHB management was initiated by modulating the hosts’ immune system through immune therapy. This review will discuss the nature and design of innovative immune therapy for CHB.

Therapeutic vaccination for treatment of chronic hepatitis B

Chronic hepatitis B infection remains a serious global health threat, contributing to a large number of deaths through liver cirrhosis and hepatocellular carcinoma. Current treatment does not eradicate disease, and therefore new treatments are urgently needed. In acute hepatitis B virus (HBV) a strong immune response is necessary to clear the virus, but in chronic infection the immune response is weakened and dysfunctional. Therapeutic vaccination describes the process of inoculating individuals with a non‐infective form of viral antigen with the aim of inducing or boosting existing HBV‐specific immune responses, resulting in sustained control of HBV infection. In this review we outline the rationale for therapeutic vaccination in chronic HBV infection, discuss previous and ongoing trials of novel HBV therapeutic vaccine candidates and outline strategies to improve vaccine efficacy going forward.

Designing the next-generation therapeutic vaccines to cure chronic hepatitis B: focus on antigen presentation, vaccine properties and effect measures

In the mid‐90s, hepatitis B virus (HBV)‐directed immune responses were for the first time investigated in detail and revealed suboptimal T‐cell responses in chronic HBV patients. Based on these studies, therapeutic vaccination exploiting the antigen presentation capacity of dendritic cells to prime and/or boost HBV‐specific T‐cell responses was considered highly promising. Now, 25 years later, it has not yet delivered this promise. In this review, we summarise what has been clinically tested in terms of antigen targets and vaccine forms, how the immunological and therapeutic effects of these vaccines were assessed and what major clinical and immunological findings were reported. We combine the lessons learned from these trials with the most recent insights on HBV antigen presentation, T‐cell responses, vaccine composition, antiviral and immune‐modulatory drugs and disease biomarkers to derive novel opportunities for the next generation of therapeutic vaccines designed to cure chronic HBV either alone or in combination therapy.

Therapeutic efficacy of hepatitis B virus vaccine in treatment of chronic HBV infections: A systematic review and meta-analysis

There is a need for improved treatment of patients with chronic hepatitis B (CHB). We reviewed the literature to explore the efficacy of HB vaccines alone or in combination therapy (CT) with antiviral drugs in CHB patients and to meta-analyze data from randomized controlled trials. We conducted a systematic search in ten databases. All studies investigating the efficacy of HBV vaccine in HBV infected patients were included with no restrictions. Among 1359 studies initially identified, 23 studies (n = 1956 patients) were included for the final analysis. CT showed a significant reduction of HBV DNA compared with analogue monotherapy (AM) at the 12-month follow-up period (odds ratio (OR) = 2.835, 95% confidence interval (CI) [1.275, 6.306], p = .011). Additionally, CT also remarkably induce HbsAg loss in comparison with AM (OR = 11.736, 95% CI [1.841, 74.794], p = .009). Our pooled data revealed no difference between treatment and control regarding alanine aminotransferase normalization, HBeAg seroconversion, and HBeAg disappearance. In addition, CT using vaccine and NAs resulted in a statistically significant higher incidence of adverse effects than AM. The therapeutic effects of combination therapy for patients with CHB were encouraging, but future studies need to investigate all possible treatment combinations and assess their cost-effectiveness.

Toward a Functional Cure for Hepatitis B: The Rationale and Challenges for Therapeutic Targeting of the B Cell Immune Response

The central role of the cellular immune response in the control and clearance of the hepatitis B virus (HBV) infection has been well-established. The contribution of humoral immunity, including B cell and antibody responses against HBV, has been investigated for a long time but has attracted increasing attention again in recent years. The anti-HBs antibody was first recognized as a marker of protective immunity after the acute resolution of the HBV infection (or vaccination) and is now defined as a biomarker for the functional cure of chronic hepatitis B (CHB). In this way, therapies targeting HBV-specific B cells and the induction of an anti-HBs antibody response are essential elements of a rational strategy to terminate chronic HBV infection. However, a high load of HBsAg in the blood, which has been proposed to induce antigen-specific immune tolerance, represents a major obstacle to curing CHB. Long-term antiviral treatment by nucleoside analogs, by targeting viral translation by siRNA, by inhibiting HBsAg release via nucleic acid polymers, or by neutralizing HBsAg via specific antibodies could potentially reduce the HBsAg load in CHB patients. A combined strategy including a reduction of the HBsAg load via the above treatments and the therapeutic targeting of B cells by vaccination may induce the appearance of anti-HBs antibodies and lead to a functional cure of CHB.

Therapeutic vaccination for chronic hepatitis B: A systematic review and meta-analysis

Therapeutic vaccines may be promising treatments for chronic hepatitis B (CHB), but their clinical efficacy and safety are unclear. We conducted a systematic review of the evidence for the efficacy and safety of therapeutic vaccines in CHB patients. We searched PubMed, EMBASE and Google Scholar from 1990 until present and abstracts from EASL, APASL and AASLD from 2012 to 2017 and selected randomized controlled trials of CHB patients, comparing therapeutic vaccines with no treatment or standard of care. The Cochrane Risk of Bias tool v2.0 and GRADE method were used. Analyses were stratified by hepatitis B e antigen (HBeAg) status and the comparator (therapeutic vaccines vs no treatment, or therapeutic vaccines + standard of care vs standard of care). Efficacy outcomes were HBeAg seroconversion, hepatitis B virus DNA reduction and hepatitis B virus surface antigen (HBsAg) loss, measured at the end of treatment or end of follow-up. Effects were reported as risk differences with 95% confidence intervals using a random effects model. Fifteen studies were included. A wide variety of therapeutic vaccines were tested. For HBeAg clearance at the end of follow-up, when comparing therapeutic vaccines vs no therapy, RD = 0.01, 95% CI -0.05 to 0.07, and when comparing therapeutic vaccines + standard of care vs standard of care, RD = 0.03, 95% CI -0.03 to 0.09. For HBVDNA reduction at the end of follow-up, when comparing therapeutic vaccines vs no therapy, RD = -0.03, 95% CI -0.08 to 0.02, and when comparing therapeutic vaccines + standard of care, RD = 0.15, 95% CI 0.02-0.28. There were only a few studies on HBsAg loss, and hence, the findings were inconclusive. The only efficacy finding was HBVDNA reduction at the end of follow-up for therapeutic vaccines + standard of care vs standard of care; otherwise, therapeutic vaccines do not appear to be efficacious for the treatment of CHB, but were limited by few RCTs, suboptimal therapeutic vaccines and patient selection.

Novel insights into immunotherapy for hepatitis B patients

The possible use of immunotherapy for hepatitis B has emerged for two major reasons: (1) chronic hepatitis B (CHB) is an immune-mediated pathological condition, and (2) commercially available antiviral drugs are of limited efficacy. Although various immunomodulatory agents have been used to treat patients with CHB during the last three decades, there is currently no consensus among physicians and hepatologists regarding the suitability of immunotherapy for patients with CHB. However, new insights into immunotherapy for CHB have emerged; these may facilitate design of effective and tolerable immunotherapy regimens for these patients. This review provides a comprehensive overview of immunotherapy for CHB.

Immune therapy for hepatitis B

Although several antiviral drugs are now available for treatment of patients with chronic hepatitis B (CHB), sustained off-treatment clinical responses and containment of CHB-related complications are not achieved in majority of CHB patients by antiviral therapy. In addition, use of these drugs is endowed with substantial long term risk of viral resistance and drug toxicity. The infinite treatment regimens of antiviral drugs for CHB patients are also costly and usually unbearable by most patients of developing and resource-constrained countries. Taken together, there is a pressing need to develop new and innovative therapeutic approaches for CHB patients. Immune therapy seems to be an alternate therapeutic approach for CHB patients because impaired or distorted or diminished immune responses have been detected in most of these patients. Also, investigators have shown that restoration or induction of proper types of immune responses may have therapeutic implications in CHB. Various immunomodulatory agents have been used to treat patients with CHB around the world and the outcomes of these clinical trials show that the properties of immune modulators and nature and designing of immune therapeutic regimens seem to be highly relevant in the context of treatment of CHB patients. In this review, the general properties and specific features of immune therapy for CHB have been discussed for developing the guidelines of effective regimens of immune therapy for CHB.

Treatment of children with HBeAg-positive chronic hepatitis B: a systematic review and meta-analysis

BACKGROUND

Effective management of children with chronic hepatitis B is still an unresolved issue.

AIM

To assess the outcome of different therapeutic regimens among children with HBeAg-positive chronic hepatitis B.

METHODS

Electronic database searches identified clinical trials that completed specific periods of treatment and follow-up. Sustained response rates were defined by the loss of HBV DNA and HBeAg, and by the normalization of liver enzymes. The loss of HBsAg and seroconversion to anti-HBs were also listed.

RESULTS

Our searches found 20 eligible articles (1112 enrolled patients, 2-18 years old). Interferon-alpha therapy showed significantly higher sustained response rate and loss of HBsAg than no therapy (Odd's ratio 3.0, 95% confidence interval 1.6-5.4; and 2.3, 1.1-11.3, respectively). The sustained response rate was not significantly different between interferon and interferon plus lamivudine, or plus prednisone, or plus hepatitis B vaccine; this rate was significantly higher for interferon compared with combined interferon plus levamisole or vitamin E.

CONCLUSION

Interferon-alpha is still the most effective treatment option for children with HBeAg-positive chronic hepatitis B. Randomized trials are warranted for further comparing interferon to newer antiviral agents in terms of efficacy, safety, emergence of mutant variants, and cost/benefit ratio.

Designing immune therapy for chronic hepatitis B

Presently-available antiviral drugs may not be a satisfactory option for treatment of patients with chronic hepatitis B (CHB). In spite of presence of several antiviral drugs, sustained off-treatment clinical responses are not common in CHB patients treated with antiviral drugs. In addition, antiviral drug treatment may have limited effects on blocking the progression of HBV-related complications. However, substantial long-term risk of viral resistance and drug toxicity are related with maintenance antiviral therapy in CHB patients with presently-available antiviral agents. The infinite treatments with antiviral drugs for CHB patients are also costly and may be unbearable by most patients of developing and resource-constrained countries. In this situation, there is pressing need to develop new and innovative therapeutic approaches for patients with chronic hepatitis B virus (HBV) infection. Immune therapy has emerged as an alternate therapeutic approach for CHB patients because studies have shown that host immunity is either impaired or derailed or distorted or diminished in CHB patients compared to patients with acute resolved hepatitis B who contain the HBV replication and control liver damages. Both non antigen-specific immune modulators and HBV antigen-specific agents have been used in CHB patients during last three decades. However, similar to antiviral therapy, the ongoing regimens of immune therapeutic approaches have also been unable to show real promises for treating CHB patients. The concept of immune therapy for treating CHB patients seems to be rationale and scientific, however, concerns remain about suitable designs of immune therapy for CHB patients.

Treatment options for chronic hepatitis B and C infection in children

There has been a dramatic increase in treatment options for both chronic hepatitis B (CHB) and chronic hepatitis C (CHC) infection in adults over the past 5-10 years, resulting in standardized regimes for initial treatment, relapsers and even infection in the setting of recurrence post-liver transplantation. These regimes have resulted in the halting of the disease progression, reduction in the risk of hepatocellular carcinoma and removal of these infections as a contraindication for liver transplantation. However, treatment in children must be considered carefully in the context of the natural history of these infections and host factors, particularly the immunological mileu, which may affect response to therapy. The as yet unknown long-term effects of medications must also be balanced with the probability of significant life-long morbidity or mortality from chronic hepatitis and its complications. Furthermore, the development of drug resistance, particularly in the case of CHB, has significant implications for the pediatric patient who may exhaust effective therapeutic options at a relatively young age. For these reasons, initiation of therapy must be based on sound criteria. Based on the current data, we recommend that therapy should be offered to children with CHB who have an elevation in alanine aminotransferase (>2-3 x upper limit of normal) for more than 6 months. Therapy with interferon-alpha should be offered in the majority of cases with the aim of immune clearance as measured by early antigen seroconversion. By contrast, treatment indication for CHC in children remains controversial. If used, combination therapy with pegylated interferon and ribavirin is likely to produce the highest rates of sustained viral response.

HBsAg, HBcAg, and combined HBsAg/HBcAg-based therapeutic vaccines in treating chronic hepatitis B virus infection

BACKGROUND

As the host immunity is diminished in patients with chronic hepatitis B (CHB), different approaches have been used to up-regulate their immune responses to produce therapeutic effects. But, cytokines, growth factors and polyclonal immune modulators could not exhibit sufficient therapeutic effects in these patients. Immune therapy with HBV-related antigens (vaccine therapy) has been used in CHB patients. But there is a paucity of information about the design of HBV antigen-based immune therapy in these patients.

DATA SOURCE

Preclinical and clinical studies on immune therapy with HBsAg-based vaccine, HBcAg and combination of HBsAg/HBcAg-based vaccines have been discussed.

RESULTS

HBsAg-based prophylactic vaccine was used as an immune therapeutic agent in CHB patients; however, monotherapy with HBsAg-based immune therapy could not lead to sustained control of HBV replication and/or liver damages. HBsAg-based vaccine was used as a combination therapy with cytokines, growth factors, and antiviral drugs. HBsAg-based vaccine was also used for cell-based therapy. However, satisfactory therapeutic effects of HBsAg-based vaccine could not be documented in CHB patients. In the mean time, evidences have supported that HBcAg-specific immunity is endowed with antiviral and liver protecting capacities in CHB patients. Recent data concentrate on the clinical use of combined HBsAg- and HBcAg-based vaccines in CHB patients.

CONCLUSION

Antigen-based immune therapy with HBV-related antigens may be an alternative method for the treatment of CHB patients but proper designs of antigens, types of adjuvants, dose of vaccinations, and routes of administration need further analyses for the development of an effective regimen of immune therapy against HBV.

Non-antigen-specific and antigen-specific immune therapies for chronic hepatitis B: evidences from laboratory benches and patient's bedsides

INTRODUCTION

Due to unsatisfactory therapeutic efficacy and considerable side effects of antiviral drugs in patients with chronic hepatitis B (CHB), immunotherapy has emerged as an alternative approach. CHB immunotherapy may be categorized into two main types: i) non-antigen-specific immune therapy and ii) hepatitis B virus (HBV) antigen-specific immune therapy. Although different immune modulators have been used in CHB patients for the last two to three decades, the nature and design of ongoing regimens of immunotherapeutic approaches need considerable modifications.

AREAS COVERED

In this review, the authors have outlined the relevant immunotherapies for CHB patients that have been used for the last two to three decades. The mechanisms underlying the limited therapeutic efficacy of available therapeutic agents for CHB patients have been discussed to aid in the development of an effective therapeutic approach for these patients.

EXPERT OPINION

Circumstantial evidence indicates that a better regimen of immunotherapy may be developed using different HBV-related antigens or combinations of two or more HBV-related antigens, or combinations of HBV-related antigens and antiviral drugs. However, the capacity of 'inducible immunity' by immune modulators to cure or block progression of liver diseases in CHB patients needs to be addressed.

T cell immunopathogenesis and immunotherapeutic strategies for chronic hepatitis B virus infection

Hepatitis B is caused by the host immune response and T cells play a major role in the immunopathogenesis. More importantly, T cells not only destroy hepatocytes infected by hepatitis B virus (HBV), but also control HBV replication or eradicate HBV in a noncytolytic manner. Therefore, analysis of T cell immune response during acute and chronic HBV infection is important to develop a strategy for successful viral control, which could lead to immunotherapy for terminating persistent HBV infection. There have been many attempts at immunotherapy for chronic HBV infection, and some have shown promising results. High viral load has been shown to suppress antiviral immune responses and immunoinhibitory signals have been recently elucidated, therefore, viral suppression by nucleos(t)ide analogs, stimulation of antiviral immune response, and suppression of the immunoinhibitory signals must be combined to achieve desirable antiviral effects.

Interferon-alpha-2a and zinc combination therapy in children with chronic hepatitis B infection

Zinc has been reported to enhance the response to interferon (IFN) or PEG-IFN plus ribavirin therapy, improve liver function, and ameliorate hematologic side effects in patients with chronic hepatitis C. However, the role of zinc supplementation during IFN therapy in chronic hepatitis B infection (CHB) remains unclear. We therefore aimed to report the results of zinc and IFN-alpha-2a therapy in children with CHB. Twenty-two naive, HBeAg-positive children (mean age 10.4 ± 4.4 years) received IFN-α2a (9 MU/m(2) sc) for 6 months plus peroral zinc (7.5 mg/day for <10 years and 10 mg/day for >10 years) for 12 months. Serum zinc, alanine aminotransferase (ALT), complete blood count, hepatitis B virus DNA (HBV DNA), and serological markers were measured. Histological (HR) and sustained response (SR) were evaluated at 6 months after completion of therapy. Normalization of ALT, HBeAg seroconversion, and HBV DNA < 10,000 copies/ml were considered as SR. HR was defined as decrease in Knodell histological activity index (HAI) score by at least 2 points compared to baseline. End of therapy ALT level and log HBV DNA were significantly lower than pretherapy levels (p = 0.001 and p = 0.001, respectively), while zinc level was not different. Portal inflammation score significantly decreased after therapy (p = 0.043), however, total HAI and other HAI components were not different. SR and HR were 25% and 52.9%. In conclusion as a first study investigating the effect of zinc and IFN combination therapy in children with CHB, SR and HR rates were not better than previously reported monotherapy or combination therapies.

Systematic review: combination therapies for treatment-naïve chronic hepatitis B

BACKGROUND

There is a renewed interest in use of combination therapies in treatment-naïve chronic hepatitis B (CHB) because of limitations of monotherapies.

AIM

To discuss the current status of combination therapies in treatment-naïve CHB.

METHODS

PubMed search was done using 'combination', 'sequential' and 'chronic hepatitis B' as the search terms.

RESULTS

The two most popular combination therapies include 'combination of nucleos(t)ide analogues' and 'combination of interferons and nucleos(t)ide analogues'. Combination therapies using two nucleos(t)ide analogues do not lead to higher long-term efficacy. However, addition of a nucleos(t)ide analogue with a good resistance profile to a nucleos(t)ide analogue with a lower genetic barrier to resistance decreases the risk of emergent resistance to the latter. Greater sustained virological, biochemical and seroconversion rates are observed with addition of lamivudine to conventional interferon, but pegylated-interferon monotherapy is equally effective as combination with lamivudine. Again, resistance to lamivudine is lower with its combination with interferons.

CONCLUSIONS

The answer to the question whether hepatitis B can be treated better with combination or monotherapy remains largely unknown. Additional trials are warranted of combination therapies of peginterferon and potent nucleos(t)ide analogues or therapies with the combined use of nucleos(t)ide analogues or immunomodulators.

Novel Approaches to New Therapies for Hepatitis B Virus Infection

Hepatitis B is one of the most prevalent viral diseases in the world. It leads to chronic liver disease in 10% of infected individuals, putting them at an increased risk for liver-related morbidity and mortality from complications of cirrhosis and hepatocellular carcinoma. Despite the success of universal hepatitis B vaccination in many countries, this disease remains a major public health problem, resulting in more than 500,000 deaths per year. Although the current therapy for chronic hepatitis B (CHB) is effective, it is not optimal; novel approaches to the management of CHB are needed. An improved understanding of virus-host interactions, advances in gene therapy, the development of molecular therapies targeted at different stages of the hepatitis B virus life cycle, and new insights into various approaches of immune modulation will lead to the development of better therapeutic agents for the management of CHB. These advances herald a new era of combination therapy. In this review, we will discuss emerging therapies and potential mechanisms, and highlight the promises and pitfalls of these new treatment strategies.

Hepatitis B virus and hepatitis C virus infections in children

PURPOSE OF REVIEW

To analyse the most relevant recent information on efficacy, duration and coverage of anti-hepatitis B virus vaccination; correlates of mother-to-child hepatitis C virus transmission; the natural history and outcomes of hepatitis B and C virus infections in children; the efficacy and safety of specific therapies.

RECENT FINDINGS

Insufficient hepatitis B virus vaccine coverage and incomplete or delayed vaccine cycles need improvement in many countries. Hepatitis B virus mutants may explain some fulminant hepatitis in perinatally infected infants and vaccine failures. No interventions to prevent vertical hepatitis C virus transmission have been identified. Spontaneous clearance of hepatitis B is lower in children than in adults, while the rates appear to be similar for hepatitis C. The disease progression is slower for both infections in childhood. Several studies support the efficacy and safety of interferons and lamivudine in chronic hepatitis B or of interferons and ribavirin in chronic hepatitis C in children, but the optimal therapy remains unclear.

SUMMARY

There are doubts as to the long-term persistence of anti-hepatitis B immunization in low-endemicity areas. Routine hepatitis C virus testing in pregnancy is not recommended as there are no available prophylactic measures. Although hepatitis B and C virus infections are usually asymptomatic or with mild manifestations in childhood, concerns around their long-term clinical impact suggest the need for early treatment. Children should preferably be treated in the context of targeted trials for a better understanding of the efficacy and tolerance of drugs currently used in adults.

Emerging treatments in chronic hepatitis B

Although the management of chronic hepatitis B has improved over the last decade, none of the available therapeutic agents, IFN-alpha, lamivudine and adefovir dipivoxil, can achieve sustained off-therapy responses in most cases. Therefore, several newer, mainly antiviral and immunomodulatory agents, are being evaluated. Pegylated IFN-alpha(2a) has been shown to be more effective than lamivudine or standard IFN-alpha monotherapy in achieving post-therapy biochemical and virological responses, and is expected to be licensed soon for the treatment of chronic hepatitis B. Newer antiviral agents, such as entecavir and telbivudine, appear to be quite effective initially, but their sustained off-therapy response rates remain unknown. The preliminary data of monotherapies with immunomodulatory agents, or of combination therapies, have been rather disappointing. Long-term maintenance treatment with antiviral agent(s) with good safety and tolerability profiles and low resistance rates appears to be the most realistic future therapeutic option for most chronic hepatitis B patients.