Sustained response after a 2-year course of lamivudine treatment of hepatitis B e antigen-negative chronic hepatitis B

Systematic review: Clinical outcomes of discontinuation of oral antivirals in hepatitis B-related liver cirrhosis

Background

Discontinuation of Nucleos(t)ide analogs (NAs) remains one of the most controversial topics in the management of hepatitis B-related liver cirrhosis. However, clinical outcomes after NAs discontinuation have not been studied.

Aim

The aim of this systematic review is to evaluate existing data on clinical outcomes of NAs withdrawal in chronic hepatitis B (CHB) patients with cirrhosis.

Methods

A literature search (until May 2022) was performed in order to identify all published studies including hepatitis B-related cirrhotic patients who discontinued NAs in virological remission with off-therapy follow-up >12 months.

Results

Nineteen studies with 1,287 hepatitis B-related cirrhotic patients were included. Most cirrhotic patients were compensated and achieved complete virological suppression when they stopped the antiviral therapy. The pooled proportions of virological relapse and clinical relapse after NAs discontinuation in cirrhotic patients were 55.23 (95% CI: 40.33-69.67) and 43.56% (95% CI: 26.13-61.85), respectively. HBsAg loss was observed in 56 of 500 (pooled proportion = 13.68%, 95% CI: 5.82-24.18) cirrhotic patients. And the pooled proportions of HCC development, hepatic decompensation and overall mortality were 8.76 (95% CI: 2.25-18.95), 3.63 (95% CI: 1.31-7.03), and 0.85% (95% CI: 0.35-1.57), respectively, after NAs discontinuation in cirrhotic patients.

Conclusion

In hepatitis B-related compensated cirrhosis, who have achieved complete virological suppression, discontinuation of oral antivirals still carries a high relapse rate, but the incidence of adverse events is generally low and controlled during follow-up of at least 12 months. Of attention is that discontinuation of NAs can achieve a high rate of HBsAg seroclearance. This study may be helpful in the management of NAs in cirrhotic patients.

Systematic review registration

http://www.crd.york.ac.uk/PROSPERO, identifier: CRD42020170103.

Risks and Benefits of Discontinuation of Nucleos(t)ide Analogue Treatment: A Treatment Concept for Patients With HBeAg-Negative Chronic Hepatitis B

Systematic discontinuation of long-term treatment with nucleos(t)ide analogues (NAs) is one strategy to increase functional cure rates in patients with chronic hepatitis B e antigen (HBeAg)-negative hepatitis B. Currently, available study results are heterogeneous; however, long-term hepatitis B surface antigen (HBsAg) loss rates of up to 20% have been reported in prospective trials. This review proposes criteria that can be used when considering NA discontinuation in patients with chronic hepatitis B virus (HBV). Discontinuing NA treatment frequently results in a virologic and biochemical relapse that runs through different phases: the lag phase, reactivation phase, and consolidation phase. The HBV-DNA flares observed during the reactivation phase are often transient and most likely represent a trigger for inducing a long-term immune control by specific CD8+ T cells, and therefore do not need immediate interventions but close follow-up evaluation. Low HBsAg levels at the time of treatment cessation predict a positive long-term response to NA discontinuation associated with a higher likelihood of HBsAg clearance. Other host and viral biomarkers are currently under evaluation that may prove to be helpful to further characterize the population that may benefit most from the finite NA treatment concept. Potential harmful biochemical flares during the reactivation phase need to be identified early and can be effectively terminated by reintroducing NA treatment. Hepatic decompensation represents a risk to patients with cirrhosis undergoing NA discontinuation. Therefore, the finite NA approach should only be considered after excluding advanced fibrosis and cirrhosis and if a close follow-up of the patient and supervision by an experienced physician can be guaranteed. Conclusion: For selected patients, NA discontinuation has become a powerful tool to achieve control over HBeAg-negative HBV infections. Its significant effect represents a challenge to novel treatment approaches, but it may also serve as their enhancer.

Challenges in the discontinuation of chronic hepatitis B antiviral agents

Long-term antiviral treatment of chronic hepatitis B patients has been proven to be beneficial in reducing liver-related complications. However, lengthy periods of daily administration of medication have some inevitable drawbacks, including decreased medication adherence, increased cost of treatment, and possible long-term side effects. Currently, discontinuation of antiviral agent has become the strategy of interest to many hepatologists, as it might alleviate the aforementioned drawbacks and increase the probability of achieving functional cure. This review focuses on the current evidence of the outcomes following stopping antiviral treatment and the factors associated with subsequent hepatitis B virus relapse, hepatitis B surface antigen clearance, and unmet needs.

Long-term clinical outcome of HBeAg-negative chronic hepatitis B patients who discontinued nucleos(t)ide analogues

BACKGROUND & AIMS

Discontinuation of nucleos(t)ide analogues (NA) remains a debatable issue in HBeAg-negative chronic hepatitis B (CHB). This study aimed to address the outcome of HBeAg-negative CHB patients who discontinued NA therapy.

METHODS

This prospective study included 57 non-cirrhotic HBeAg-negative Caucasian CHB patients who discontinued NA therapy after median virological remission of 6 years. All patients had regular blood tests. Virological relapse was defined as HBV DNA > 2000 IU/mL or >20 000 IU/mL and biochemical relapse as ALT > ULN (40 IU/mL) or >2xULN. All patients with retreatment predefined criteria restarted entecavir or tenofovir.

RESULTS

Of the 57 patients, 29 remained without retreatment after median follow-up of 65 months (range: 36-87) following treatment discontinuation. At 3, 6, 12, 24, 36 and 48 months, cumulative rates of retreatment were 16%, 20%, 32%, 35%, 46% and 50%, while the proportion of patients with HBV DNA < 2000 IU/mL and ALT < ULN were 73%, 60%, 52%, 52%, 47% and 37% respectively. All patients had virological and biochemical response after retreatment. No patient developed liver failure, hepatocellular carcinoma or death. Cumulative rates of HBsAg loss were 2%, 4%, 7%, 10% and 20% at 3, 6, 12, 24 and 36 months. HBsAg levels < 100 IU/mL at the end of NA treatment could predict HBsAg loss (P = .001).

CONCLUSIONS

Our study supports that NA therapy can be safely stopped in non-cirrhotic patients with HBeAg-negative CHB. Over a median follow-up of more than 5 years, half of the patients remained without retreatment with a substantial proportion of them achieving functional cure.

Perspectives on stopping nucleos(t)ide analogues therapy in patients with chronic hepatitis B

Long-term treatment with nucleos(t)ide analogs (NAs) is the current first line therapy for patients with chronic hepatitis B (CHB), recommended by most of the current guidelines. NAs prevent disease progression, liver failure, decrease the risk of hepatocellular carcinoma (HCC), and have favorable safety profiles. However, low rates of on-therapy functional cure (hepatitis B surface antigen [HBsAg] loss), which is regarded as the optimal end point, prevent many patients from stopping NA therapy with the need for a lifelong treatment. The higher likelihood of HBsAg loss associated with stopping as compared to continuing NAs has got a lot of attention recently. Recommendations regarding endpoints allowing for safely stopping NA therapy differ between international guidelines. Whereas in HBeAg-positive patients, HBeAg seroconversion with at least one year of consolidation therapy is an acceptable endpoint of treatment, the recommendations for HBeAg-negative ones differ. Some guidelines propose ≥3 years of HBV DNA undetectability to stop NA while others regard HBsAg loss as the only acceptable endpoint. Stopping NA can lead to substantial rates of virologic relapses and consequent ALT flares in some cases. Moreover, no reliable predictor(s) of post-NA relapses have been identified so far. Quantitative HBsAg is becoming an increasingly promising marker to predict safe NA cessation. On the other hand, investigating the role of the immune system in mediating sustained virologic responses after NA withdrawal is needed to suggest immunological biomarkers to safely stop NA. In this article, we will review relevant literature regarding NA stopping strategy and discuss promising viral and immunological biomarkers to predict antiviral responses and thus to help identify patients who are more likely to achieve HBsAg seroclearance.

Current practice and contrasting views on discontinuation of nucleos(t)ide analog therapy in chronic hepatitis B

Introduction: Long-term, even indefinite treatment with nucleos(t)ide analogs (NAs) is the current first-line therapy for patients with chronic hepatitis B (CHB), regardless of its histological stage. Guidelines and recommendations on duration and endpoints of NA therapy in CHB are not identical and change over time.Areas covered: The authors review NA discontinuation approaches and views with an emphasis on HBeAg-negative patients based on published studies relevant to the topic, stressing on whether or not the optimal endpoint of HBsAg loss is practically achievable.Expert opinion: Discontinuation of NA therapy in HBeAg-negative noncirrhotic patients has to be considered after long-term effective treatment with controlled liver disease activity, undetectable viremia, and significant decline in serum HBsAg titers. Close post-treatment monitoring is required for early intervention in cases of severe clinical relapse. Immediate retreatment hampers the favorable outcome of HBsAg clearance (functional cure) and should be avoided in transient ALT flares. Predictors of such relapses are still under investigation and include viral and patient factors. For HBeAg-positive noncirrhotic patients, there is wide acceptance of the endpoint of HBeAg seroconversion, after a long consolidation period.

Finite nucleos(t)ide analog therapy in HBeAg-negative chronic hepatitis B: an emerging paradigm shift

Potent nucleos(t)ide analogs (NUC), such as entecavir and tenofovir disoproxil fumarate, are able to suppress HBV DNA to undetectable level. These agents have no direct action on cccDNA, which is a very stable template for HBV production, hence long-term or even life-long NUC therapy is required in HBeAg-negative patients to maintain HBV suppression and to achieve the ultimate goal of HBsAg loss. However, there are concerns of indefinite or life-long NUC therapy, including drug resistance, financial burden, adherence and willingness for indefinite long-term NUC therapy. Patients lost to follow-up and hence, not monitored may risk severe relapse that may deteriorate to hepatic decompensation or even hepatic failure. This Review integrated the cumulated evidence and assessed the strategy of finite NUC therapy in HBeAg-negative patients which was first tried in early 2000s. Earlier Asian findings that 2-year NUC therapy is feasible and safe have founded APASL stopping rule for patients on NUC therapy over 2-3 years since 2008. Subsequent studies have supported the strategy of finite NUC therapy, which has finally been accepted as an option by American and European liver associations since 2016. More recent studies have further shown greatly increased HBsAg loss rate (up to 5-year 39%) after stopping NUC therapy. The cumulated evidence has shown that the paradigm shift from indefinite long-term therapy to finite NUC therapy in HBeAg-negative patients is emerging. More studies are needed to fine-tuning the strategy including research for the optimal duration of consolidation therapy, timing to stop and to start re-treatment.

Assessment of histopathological alterations in patients with chronic hepatitis B infection following long-term oral antiviral therapy

Objectives:

To evaluate the histopathological changes in the liver after oral antiviral therapy in patients with chronic hepatitis B.

Methods:

A total of 79 HBeAg-negative and positive patients who had been on lamivudine, entecavir, or tenofovir disoproxil for at least 3 years prior to inclusion were enrolled between March 2015 and 2016, retrospectively. There were 23 patients on lamivudine, 21 patients on entecavir, and 35 on tenofovir. All patients underwent a follow-up liver biopsy. Biochemical, serological, virological and histopathological data were recorded in all patients and were compared after at least 3 years of treatment with oral antiviral agents.

Results:

Histological activity index scores were reduced in patients who received lamivudine (p=0.011), entecavir (p=0.002), and tenofovir (p=0.001). Also, in contrast with a significant improvement in fibrosis scores in lamivudine (p=0.033) and tenofovir (p=0.001) groups no improvements were found in patients who received entecavir (p=0.090).

Conclusion:

Long term treatment with oral antiviral agents was associated with biochemical, virological, serological, and histopathological improvements. Long-term use of anti-viral agents as well as continuous suppression of HBV DNA are prerequisites for histopathological improvement.

Is it possible to stop nucleos(t)ide analogue treatment in chronic hepatitis B patients?

Chronic hepatitis B (CHB) remains a challenging global health problem, with nearly one million related deaths per year. Nucleos(t)ide analogue (NA) treatment suppresses viral replication but does not provide complete cure of the hepatitis B virus (HBV) infection. The accepted endpoint for therapy is the loss of hepatitis B surface antigen (HBsAg), but this is hardly ever achieved. Therefore, indefinite treatment is usually required. Many different studies have evaluated NA therapy discontinuation after several years of NA treatment and before HBsAg loss. The results have indicated that the majority of patients can remain off therapy, with some even reaching HBsAg seroconversion. Fortunately, this strategy has proved to be safe, but it is essential to consider the risk of liver damage and other comorbidities and to ensure a close follow-up of the candidates before considering this strategy. Unanswered questions remain, namely in which patients could this strategy be effective and what is the optimal time point at which to perform it. To solve this enigma, we should keep in mind that the outcome will ultimately depend on the equilibrium between HBV and the host’s immune system. Viral parameters that have been described as good predictors of response in HBeAg(+) cases, have proven useless in HBeAg(-) ones. Since antiviral immunity plays an essential role in the control of HBV infection, we sought to review and explain potential immunological biomarkers to predict safe NA discontinuation in both groups.

HBsAg Loss with Peg-interferon Alfa-2a in Hepatitis B Patients with Partial Response to Nucleos(t)ide Analog: New Switch Study

Background and Aims: Hepatitis B surface antigen (HBsAg) loss is seldom achieved with nucleos(t)ide analog (NA) therapy in chronic hepatitis B patients but may be enhanced by switching to finite pegylated-interferon (Peg-IFN) alfa-2a. We assessed HBsAg loss with 48- and 96-week Peg-IFN alfa-2a in chronic hepatitis B patients with partial response to a previous NA. Methods: Hepatitis B e antigen (HBeAg)-positive patients who achieved HBeAg loss and hepatitis B virus DNA <200 IU/mL with previous adefovir, lamivudine or entecavir treatment were randomized 1:1 to receive Peg-IFN alfa-2a for 48 (n = 153) or 96 weeks (n = 150). The primary endpoint of this study was HBsAg loss at end of treatment. The ClinicalTrials.gov identifier is NCT01464281. Results: At the end of 48 and 96 weeks' treatment, 14.4% (22/153) and 20.7% (31/150) of patients, respectively, who switched from NA to Peg-IFN alfa-2a cleared HBsAg. Rates were similar irrespective of prior NA or baseline HBeAg seroconversion. Among those who cleared HBsAg by the end of 48 and 96 weeks' treatment, 77.8% (14/18) and 71.4% (20/28), respectively, sustained HBsAg loss for a further 48 weeks. Baseline HBsAg <1500 IU/mL and week 24 HBsAg <200 IU/mL were associated with the highest rates of HBsAg loss at the end of both 48- and 96-week treatment (51.4% and 58.7%, respectively). Importantly, extending treatment from 48 to 96 weeks enabled 48.3% (14/29) more patients to achieve HBsAg loss. Conclusions: Patients on long-term NA who are unlikely to meet therapeutic goals can achieve high rates of HBsAg loss by switching to Peg-IFN alfa-2a. HBsAg loss rates may be improved for some patients by extending treatment from 48 to 96 weeks, although the differences in our study cohort were not statistically significant. Baseline and on-treatment HBsAg may predict HBsAg loss with Peg-IFN alfa-2a.

Why not to stop antiviral treatment in patients with chronic hepatitis B

Treatment of chronic hepatitis B with entecavir or tenofovir leads to viral suppression in almost all patients. However, prolonged or lifelong treatment is necessary. At present, there is no consensus among the three major guidelines for the treatment of chronic hepatitis B on whether or not to stop antiviral treatment. One of the main reasons for this controversy is that virological relapse has been well documented in patients with chronic hepatitis B who stop treatment. Relapse rate is particularly high in patients who are HBeAg-negative when treatment begins, with reported relapse rates of up to 70% 36 months after treatment discontinuation. Moreover, hepatic decompensation, jaundice and death have been described in patients with cirrhosis after treatment discontinuation. The main reason for stopping antiviral treatment is related to cost, however there is no robust evidence to support treatment discontinuation in most patients.

Stopping long-term treatment with nucleos(t)ide analogues is a favourable option for selected patients with HBeAg-negative chronic hepatitis B

The immune response against the infection is impaired in patients with chronic hepatitis B, and although HBV DNA can effectively be suppressed by nucleos(t)ide analogues (NA), durable immune control is only established in a minority of patients. This especially applies in HBeAg-negative patients who usually must receive lifelong NA treatment. Calculated withdrawal of NA leads to a relapse of HBV DNA in most patients. There is evidence that this sudden exposure of viral antigens can trigger immune control in some patients which may result in HBsAg loss or a form of immune control, then sustained low HBV DNA levels and normal alanine aminotransferase (ALT). In the first prospective randomized trial investigating tenofovir treatment cessation in HBeAg-negative patients, most patients did not need retreatment after NA cessation, although all patients showed a transient relapse in HBV DNA. HBsAg loss was identified in almost 20% nearly 3 years after stopping NA. Further confirmation of these findings is needed in larger randomized trials and patients who are most likely to benefit from finite therapy must be identified to individualize NA stopping strategies. However, these results suggest that in patients without risk factors such as cirrhosis or other severe conditions, NA treatment may be stopped, as long as adequate safety rules for retreatment are followed.

Long-term response after stopping tenofovir disoproxil fumarate in non-cirrhotic HBeAg-negative patients - FINITE study

BACKGROUND & AIMS

There is currently no virological cure for chronic hepatitis B but successful nucleos(t)ide analogue (NA) therapy can suppress hepatitis B virus (HBV) DNA replication and, in some cases, result in HBsAg loss. Stopping NA therapy often leads to viral relapse and therefore life-long therapy is usually required. This study investigated the potential to discontinue tenofovir disoproxil fumarate (TDF) therapy in HBeAg-negative patients.

METHODS

Non-cirrhotic HBeAg-negative patients who had received TDF for ≥4years, with suppressed HBV DNA for ≥3.5years, were randomly assigned to either stop (n=21) or continue (n=21) TDF monotherapy. Standard laboratory tests including HBV DNA viral load, HBsAg and alanine aminotransferase (ALT) measurements, and adverse event reporting were carried out during treatment and post-treatment follow-up for 144weeks.

RESULTS

Of the patients who stopped TDF therapy, 62% (n=13) remained off-therapy to Week 144. Median HBsAg change in this group was -0.59log₁₀IU/ml (range -4.49 to 0.02log₁₀IU/ml) vs. 0.21log₁₀IU/ml in patients who continued TDF therapy. Four patients (19%) achieved HBsAg loss. Patients stopping therapy had initial fluctuations in viral load and ALT; however, at Week 144, 43% (n=9) had either achieved HBsAg loss or had HBV DNA <2,000IU/ml. There were no unexpected safety issues identified with stopping TDF therapy.

CONCLUSIONS

This controlled study demonstrated the potential for HBsAg loss and/or sustained virological response in non-cirrhotic HBeAg-negative patients stopping long-term TDF therapy. Lay summary: Nucleos(t)ide analogue (NA) is usually a life-long therapy for HBV patients. This randomised controlled study investigated the discontinuation of tenofovir disoproxil fumarate (TDF) therapy in HBeAg-negative patients. Of the patients who stopped TDF therapy, 62% remained off-therapy to Week 144, of which 43% of patients had achieved either HBsAg loss or HBV DNA <2,000IU/ml. This offers a potential for long-term HBV-suppressed patients without cirrhosis to stop NA therapy under strict surveillance. Clinical trial number: NCT01320943.

On-treatment and off-treatment efficacy of entecavir in a real-life cohort of chronic hepatitis B patients

BACKGROUND AND AIMS

Entecavir (ETV) is a potent nucleoside analogue with high genetic barrier to resistance. In this study, real-life clinical experiences in the long-term use of ETV and the durability of its off-treatment effectiveness were analyzed.

MATERIALS AND METHODS

This study was based on a large real-life cohort of 2240 chronic hepatitis B patients treated with ETV between January 2006 and December 2012 using a centralized electronic data repository.

RESULTS

Among 2240 patients, 804 patients were treatment naive and underwent ETV monotherapy. Their mean treatment duration was 712±493 days, with a cumulative proportion of patients achieving HBV DNA less than 300 copies/ml in 85.8, 95.7, and 97.6% at years 1, 2, and 3, respectively. Predictors for earlier virologic response were female sex, lower HBV DNA, higher alanine transaminase, lower platelet count, and HBeAg negativity at baseline. In patients who achieved virologic response and HBeAg loss, the cumulative relapse rate was 91.3% in 2 years after the cessation of treatment. During the treatment, 34 patients developed hepatocellular carcinoma, among whom 30 patients had cirrhosis before treatment initiation. ETV treatment showed efficient virologic response as the treatment duration was extended, but off-treatment efficacy was not durable, and the antiviral treatment showed some limitation in preventing hepatocellular carcinoma among liver cirrhosis patients, implying that treatment cessation should be taken into consideration more carefully.

CONCLUSION

This study from a real-life cohort may provide data on treating chronic hepatitis B patients more close to everyday clinical practice.

Discontinuation of oral antivirals in chronic hepatitis B: A systematic review

The possibility of safe discontinuation of therapy with nucleos(t)ide analogues (NAs) remains one of the most controversial topics in the management of chronic hepatitis B. Therefore, we systematically reviewed the existing data on NA discontinuation in this setting and tried to identify factors affecting the probability of posttherapy remission. A literature search was performed in order to identify all published studies including patients who discontinued NAs in virological remission (VR) and were followed for ≥12 months thereafter. Twenty-five studies with 1716 patients were included. The pooled rates of durable VR remission were 51.4%, 39.3%, and 38.2% at 12, 24, and 36 months, respectively, after NA discontinuation, being relatively higher in initially hepatitis B e antigen (HBeAg)-positive patients (62.5%, 53.4%, 51.5%) than HBeAg-negative patients (43.7%, 31.3%, 30.1%) (P = 0.064). The weighted probability of durable biochemical remission was 65.4%, being numerically higher in HBeAg-positive than HBeAg-negative patients (76.2% versus 56.7%, P = 0.130). The weighted probability of hepatitis B surface antigen loss was 2.0%. The rates of durable VR did not significantly differ according to the VR definition (hepatitis B virus DNA <200, < 2000, < 20,000 IU/mL) or duration of on-therapy VR in HBeAg-positive patients, but they were significantly higher in studies with HBeAg-negative patients and on-therapy VR > 24 than ≤ 24 months (VR at 12 months off-NAs: 75.0% versus 35.6%, P = 0.005). The weighted probability of durable HBeAg seroconversion was 91.9% and 88.0% at 12 and 24 months, respectively, after NA discontinuation without being affected by the duration of on-therapy VR or consolidation therapy (>6 months in all studies).

CONCLUSION

Durable VR seems to be feasible in a substantial proportion of patients who discontinue long-term NA therapy; on-therapy VR > 24 months offers higher chances of off-NA VR in patients with HBeAg-negative chronic hepatitis B.

Off-treatment durability of antiviral response to nucleoside analogues in patients with chronic hepatitis B

BACKGROUND

Off-treatment durability of nucleoside analogue (NA) therapy in patients with chronic hepatitis B has not been well investigated. In this study we monitored antiviral effect of NA therapy and evaluated off-treatment durability after NA cessation in patients with chronic hepatitis B.

PATIENTS AND METHODS

A total of 94 consecutive patients (39 HBeAg-negative and 55 HBeAg-positive patients) who received NA therapy were followed up for approximately 9 years. We discontinued NA according to the following criteria; undetectable serum HBV-DNA by polymerase chain reaction (PCR) on three separate occasions at least 6 months apart in HBeAg-negative patients (APASL stopping recommendation), and seroconversion from HBeAg-positive to HBeAb-positive and undetectable serum HBV-DNA by PCR for at least 12 months in HBeAg-positive patients.

RESULTS

The cumulative rate of relapse after NA cessation was 48 % and 40 % in HBeAg-negative and -positive patients, respectively. Higher baseline serum alanine aminotransferase level was the only significant predictor for maintaining remission. No patients experienced decompensation after relapse. HBsAg loss occurred at an annual rate of 1.4 % and 0.4 % in HBeAg-negative and -positive patients, respectively. Hepatocellular carcinoma developed at an annual rate of 0.6 % in both HBeAg-negative and -positive patients.

CONCLUSIONS

Almost half of the patients did not relapse after cessation of NA therapy in both HBeAg-negative and -positive patients. Therefore, NA therapy could be discontinued with close monitoring if the APASL stopping recommendation is satisfied even in HBeAg-negative patients.

Cell Culture, Technology: Enhancing the Culture of Diagnosing Human Diseases

Cell culture involves a complex of processes of cell isolation from their natural environment (in vivo) and subsequent growth in a controlled environmental artificial condition (in vitro). Cells from specific tissues or organs are cultured as short term or established cell lines which are widely used for research and diagnosis, most specially in the aspect of viral infection, because pathogenic viral isolation depends on the availability of permissible cell cultures. Cell culture provides the required setting for the detection and identification of numerous pathogens of humans, which is achieved via virus isolation in the cell culture as the "gold standard" for virus discovery. In this review, we summarized the views of researchers on the current role of cell culture technology in the diagnosis of human diseases. The technological advancement of recent years, starting with monoclonal antibody development to molecular techniques, provides an important approach for detecting presence of viral infection. They are also used as a baseline for establishing rapid tests for newly discovered pathogens. A combination of virus isolation in cell culture and molecular methods is still critical in identifying viruses that were previously unrecognized. Therefore, cell culture should be considered as a fundamental procedure in identifying suspected infectious viral agent.

Pegylated interferon alfa for chronic hepatitis B: systematic review and meta-analysis

Conventional interferon alfa and nucleos(t)ide analogues, such as lamivudine, are frequently used for chronic hepatitis B (CHB) treatment, but are associated with adverse effects and viral resistance. Here we performed a systematic review and meta-analysis evaluating all studies of pegylated interferon alfa (PEG-IFNα) treatment in hepatitis B e antigen (HBeAg)-positive and HBeAg-negative patients with CHB. We searched electronic databases--PubMed, EMBASE, Cochrane Library and LILACS--for randomized controlled trials evaluating PEG-IFNα therapy between 1999 and September 2014. Virological response was the primary outcome. We identified 14 studies involving 2829 patients. Our analysis revealed that PEG-IFNα + lamivudine combination therapy produced better virological and biochemical responses than PEG-IFNα monotherapy in HBeAg-positive and HBeAg-negative patients at the end of treatment. PEG-IFNα + adefovir dipivoxil achieved better seroconversion rate than PEG-IFNα in HBeAg-positive patients at the end of treatment. The present findings demonstrated a beneficial response rate following PEG-IFNα combination therapy with nucelos(t)ides among HBeAg-positive and HBeAg-negative patients with CHB. Further trials are needed to investigate simultaneous and sequential therapy strategies.

Asian-Pacific clinical practice guidelines on the management of hepatitis B: a 2015 update

Worldwide, some 240 million people have chronic hepatitis B virus (HBV), with the highest rates of infection in Africa and Asia. Our understanding of the natural history of HBV infection and the potential for therapy of the resultant disease is continuously improving. New data have become available since the previous APASL guidelines for management of HBV infection were published in 2012. The objective of this manuscript is to update the recommendations for the optimal management of chronic HBV infection. The 2015 guidelines were developed by a panel of Asian experts chosen by the APASL. The clinical practice guidelines are based on evidence from existing publications or, if evidence was unavailable, on the experts' personal experience and opinion after deliberations. Manuscripts and abstracts of important meetings published through January 2015 have been evaluated. This guideline covers the full spectrum of care of patients infected with hepatitis B, including new terminology, natural history, screening, vaccination, counseling, diagnosis, assessment of the stage of liver disease, the indications, timing, choice and duration of single or combination of antiviral drugs, screening for HCC, management in special situations like childhood, pregnancy, coinfections, renal impairment and pre- and post-liver transplant, and policy guidelines. However, areas of uncertainty still exist, and clinicians, patients, and public health authorities must therefore continue to make choices on the basis of the evolving evidence. The final clinical practice guidelines and recommendations are presented here, along with the relevant background information.

Systematic review: cessation of long-term nucleos(t)ide analogue therapy in patients with hepatitis B e antigen-negative chronic hepatitis B

BACKGROUND

It has been debated whether finite nucleos(t)ide analogue therapy is feasible in HBeAg-negative chronic hepatitis B.

AIM

To review this issue systematically.

METHODS

Using text terms HBsAg and various nucleos(t)ide analogues, PubMed was searched between 1995 and 2014 to find studies on therapy >6 months in adult HBeAg-negative chronic hepatitis B patients with off-therapy follow-up >6 months.

RESULTS

Twenty-two studies with a total of 1732 patients were identified and included. The median duration of therapy, consolidation therapy and off-therapy follow-up ranged from 6 months to 8 years, 4 to 96 weeks and 6 to 80 months respectively. Patients were monitored with serum ALT and HBV DNA monthly in the first 1-3 months and every 3-6 months afterwards in most studies. The 1-year off-therapy 'virological relapse' (HBV DNA >2000 IU/mL) and 'clinical relapse' (HBV DNA > 2000 IU/mL + ALT elevation) occurred in <70% and <50% of the patients, respectively, and <40% of the patients received re-treatment. These rates were higher in patients with shorter treatment, shorter consolidation therapy and those treated with less potent nucleos(t)ide analogues. Off-therapy severe flares were rare and hepatic decompensation was reported in only one patient with cirrhosis. Biochemical relapse reflecting enhanced immune-mediated hepatocyte killing may lead to a higher chance for off-therapy HBsAg seroclearance and be possibly desirable.

CONCLUSION

With an appropriate stopping rule and a proper off-therapy monitoring plan, cessation of long-term nucleos(t)ide analogue therapy prior to HBsAg seroclearance in HBeAg-negative chronic hepatitis B is a feasible alternative to indefinite treatment.

Reduced risk of relapse after long-term nucleos(t)ide analogue consolidation therapy for chronic hepatitis B

BACKGROUND

Before stopping nucleos(t)ide analogue (NA) treatment in chronic hepatitis B (CHB), 6-12 months of consolidation therapy is recommended.

AIM

To investigate the effect of consolidation therapy on off-treatment outcomes in CHB patients.

METHODS

We included 94 patients who stopped NA after at least 1 year of therapy. Patients could be HBeAg-positive or HBeAg-negative at start-of-treatment, but were HBeAg-negative and had undetectable HBV DNA at time of discontinuation. Consolidation therapy was defined as treatment after the first undetectable HBV DNA (and HBeAg loss for HBeAg-positive patients) until NA cessation.

RESULTS

At 3 years, 74% of the start-of-treatment HBeAg-positive and 75% of the start-of-treatment HBeAg-negative patients developed HBV DNA >2000 IU/mL at a single time point, whereas a persistent virological relapse (≥2 tests of HBV DNA >2000 IU/mL 6 months apart within 1 year) developed in 49% of the start-of-treatment HBeAg-positive and 53% of the start-of-treatment HBeAg-negative patients. For both HBeAg-positive and HBeAg-negative patients, consolidation therapy of ≥3 years was associated with lower persistent virological relapse rates compared to <1 year (1-year relapse rate: 25% vs. 54%; P = 0.063 and 24% vs. 57%; P = 0.036, respectively). At 3 years, 9% of the HBeAg-positive and 14% of the HBeAg-negative patients became HBsAg-negative. Prolonged consolidation therapy increased the likelihood of HBsAg loss. Two cirrhotic patients developed hepatic decompensation but both recovered.

CONCLUSIONS

After nucleos(t)ide analogue discontinuation, relapse was common in patients with chronic hepatitis B. Prolongation of consolidation therapy beyond 3 years decreased the risk of persistent virological relapse and increased the likelihood of HBsAg loss.

[Is it possible to stop treatment with nucleos(t)ide analogs in patients with e-antigen negative chronic hepatitis B? Experience and new expectations]

BACKGROUND

Treatment of HBeAg-negative chronic hepatitis B (CHB) with nucleos(t)ide analogues (NA) is usually indefinite, since the loss of HBsAg, as a criterion for its discontinuation, is a rare event. Recent evidence suggests that discontinuing NA therapy may be feasible in selected patients.

OBJECTIVES

To analyze the rate of virological relapse in patients with HBeAg-negative CHB who discontinued treatment with NAs.

METHODS

We performed a single-center observational study that included 140 patients with HBsAg-negative CHB. Twenty-two patients, who received only NAs, discontinued treatment for different reasons and were subsequently monitored. All had normal ALT and AST, undetectable DNA and absence of cirrhosis or significant comorbidities before stopping treatment.

RESULTS

Twelve patients showed virologic relapse (54.54%). The mean interval between discontinuation and relapse was 6.38 months (± 1.9) (75% relapsed during the first 12 months after discontinuation). Five received adefovir, 1 lamivudine and adefovir, 1 tenofovir and 5 lamivudine alone. The mean treatment duration in this group was 38.5 months (± 4.5). The sustained response group had a higher mean age and longer treatment duration than patients with virologic relapse but these differences were not statistically significant.

CONCLUSIONS

The results suggest that NA treatment can be stopped in selected patients with CHB as long as they are not cirrhotic, have completed a minimum period of treatment, have normal ALT and sustained undetectable DNA. These patients should be closely monitored during the first year and then indefinitely.

High dose of Lamivudine and resistance in patients with chronic hepatitis B

Background. Lamivudine is the most affordable drug used for chronic hepatitis B and has a high safety profile. With the daily dose of 100 mg there is progressive appearance of resistance to lamivudine therapy. In our study we used 150 mg of lamivudine daily as a standard dose which warrants further exploration for the efficacy of the drug. Aims of the Study. To assess the efficacy of lamivudine 150 mg daily on resistance in patients with chronic hepatitis B. Methods. This retrospective study consists of 53 patients with chronic hepatitis B treated with 150 mg of lamivudine daily. The biochemical and virological response to the treatment were recorded at a 1-year and 2-, 3-, 4-, and 5-year period and time of emergence of resistance to the treatment was noted. Results. The mean age of the patients was 54 years with 80% being males. The resistance to lamivudine 150 mg daily at 1 year and 2, 3, and 5 years was 12.5%, 22.5%, 37.5%, and 60%, respectively, which is much less compared to the standard dose of 100 mg of lamivudine. Conclusions. Lamivudine is safe and a higher dose of 150 mg daily delays the resistance in patients with chronic hepatitis B.

Treatment cessation in noncirrhotic, e-antigen negative chronic hepatitis B is safe and effective following prolonged anti-viral suppression with nucleosides/nucleotides

BACKGROUND

The treatment of HBeAg-negative chronic hepatitis B (CHB) is considered to be open-ended, with no guidelines for treatment cessation.

AIM

To evaluate biochemical and virological relapse requiring retreatment in noncirrhotic HBeAg-negative CHB in patients who stopped treatment following a period of prolonged viral suppression with nucleotides/nucleosides.

METHODS

We performed a single-centre retrospective chart review of patients with HBeAg-negative CHB who maintained viral suppression for 4-5 years on anti-viral treatment, and thus subsequently stopped treatment. The primary end point of composite relapse was defined by an increase in HBV DNA >2000 IU/mL, ALT elevation above 1.25 × normal or doubling of ALT from cessation, and re-initiation of anti-viral therapy.

RESULTS

We identified 33 patients with HBeAg-negative CHB who stopped treatment following viral suppression. Mean treatment duration was 5.28 ± 2.73 years. Patients were treated with lamivudine (3), adefovir (14), entecavir (4), and tenofovir (12). Eleven (33%) patients met the primary end point of composite relapse. For individual end points, 21 (63%) patients had a viral relapse, 16 (48%) had a biochemical relapse, and 16 (48%) restarted treatment, leaving 17 (52%) patients who remained treatment-free over a median 36 months of follow-up. Lower pre-treatment ALT and detectable HBV DNA within the first month after treatment discontinuation were associated with increased rates of composite relapse (HR 1.01; P = 0.022 for ALT and HR 1.01; P = 0.038 for HBV DNA).

CONCLUSION

Patients with noncirrhotic HBeAg-negative CHB can stop treatment after greater than 4-5 years of suppressive therapy with nucleosides/nucleotides with more than 50% remaining treatment-free.

The feasibility of discontinuing lamivudine in lamivudine-resistant chronic hepatitis B patients on lamivudine and adefovir combination therapy

OBJECTIVES

This study investigated the antiviral efficacy of adefovir (ADV) rescue therapy and the feasibility of lamivudine (LAM) discontinuation in LAM-resistant chronic hepatitis B (CH-B) patients who had attained a virological response (VR) with LAM + ADV combination therapy.

METHODS

The VR and virological breakthrough (VBT) were analyzed in 106 consecutively enrolled LAM-resistant CH-B patients who received ADV rescue therapy during a mean follow-up period of 55.2 months. Seventy-four patients achieved VR, and were divided into the LAM-discontinuation group (n = 39) and the LAM-continuation group (n = 35). The VR and VBT between the 2 groups were compared.

RESULTS

For all 106 LAM-resistant CH-B patients, the overall cumulative probabilities of VR at 1, 2, 3 and 5 years of ADV rescue therapy were 40.6, 55.7, 64.6 and 81.3%, respectively. The cumulative probabilities of VBT at 1, 2, 3 and 5 years were 0, 2.9, 8.8 and 13.9%, respectively. Whether they discontinued or continued LAM after achieving VR on LAM + ADV therapy, VR and VBT were not significantly different during a mean follow-up period of 40.4 months.

CONCLUSIONS

There was a good long-term VR with ADV rescue therapy for LAM-resistant CH-B patients. Moreover, discontinuing LAM was found to be feasible for patients who attained VR during ADV + LAM therapy.

Off-treatment virologic relapse and outcomes of re-treatment in chronic hepatitis B patients who achieved complete viral suppression with oral nucleos(t)ide analogs

Background

The durability of off-treatment virologic responses has not been fully elucidated in chronic hepatitis B (CHB) patients who have previously achieved complete virologic suppression with nucleos(t)ide analog (NA) therapy. This study aimed to assess off-treatment virologic relapse rates and to characterize the outcomes of subsequent re-treatment in CHB patients who have discontinued oral NA following complete virologic suppression.

Methods

Ninety-five CHB patients who showed complete virologic suppression were withdrawn from NAs: entecavir, lamivudine, and clevudine in 67, 15, and 13 patients, respectively. Consolidation therapy was given for 6 and 12 months for HBeAg-positive and -negative CHB, respectively, before cessation. Virologic relapse was managed with the same NA that had induced complete virologic response before discontinuation.

Results

The cumulative rates of virologic relapse at 12 and 24 months were 73.8% and 87.1%, respectively. The relapse rates were independent of HBeAg positivity, HBeAg seroconversion, and type of oral NA. In a multivariate analysis, duration of oral NA therapy was the only significant predicting factor associated with off-treatment virologic relapse. Although the majority of patients regained complete virologic suppression, some patients did not respond to re-treatment with the initial NA and developed genotypic resistance.

Conclusions

NA consolidation therapy for 6 and 12 months is associated with high off-treatment virologic relapse in HBeAg-positive and -negative CHB patients, respectively. Drugs with high genetic barriers to resistance should be considered as a rescue therapy for off-treatment relapse in CHB.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2334-14-439) contains supplementary material, which is available to authorized users.

When to stop nucleos(t)ide analogues treatment for chronic hepatitis B? Durability of antiviral response

Introduction of nucleos(t)ide analogues (NAs) for oral antiviral therapy has dramatically improved the clinical outcome in patients with chronic hepatitis B (CHB). Although current international guidelines for the management of CHB provide information regarding when to begin the antiviral therapy with NAs, there is no clear consensus on when to stop the treatment, especially for those who respond to the therapy. Hepatitis B surface antigen loss has been regarded as an ideal endpoint of oral antiviral therapy with NAs, however since this is rarely achieved, practical endpoints have been suggested by the international guidelines. Despite the stopping rules recommended by the international guidelines, whether oral antiviral therapy with NAs can be safely discontinued is of major concern. While attention has been drawn to whether antiviral treatment with NAs can be a finite therapy, there is lack of sufficient data on off-treatment durability of highly potent NAs. Based on the available evidences, current guidelines for stopping NA therapy seems to be inadequate in terms of off-treatment durability, with relapse rates of more than 40% for both hepatitis Be antigen (HBeAg)-positive and HBeAg-negative patients. Therefore, further studies are required to accumulate data on off-treatment durability of highly potent NAs, and future studies are warranted to identify adequate predictive markers that could provide supplementary information to guide the timing of stopping NA therapy.

Peginterferon–α2a (40 kDa) (Pegasys®) for hepatitis B

Chronic hepatitis B virus is a serious and life threatening disease afflicting 350 million people worldwide, despite the availability of effective vaccines. Thus far, current monotherapy with conventional interferon-alpha, lamivudine and adefovir dipivoxil remains unsatisfactory. In addition, the use of conventional interferon-alpha needs to be administered subcutaneously three-times weekly and is associated with frequent adverse events. Although nucleoside/nucleotide analogs such as lamivudine and adefovir dipivoxil are well tolerated and can normalize serum alanine aminotransaminase rapidly, 1-year therapy with either lamivudine or adefovir dipivoxil results in low hepatitis B e antigen seroconversion rates. In hepatitis B e antigen-negative patients, most would relapse after lamivudine has been discontinued. Peginterferon-alpha2a, an immunomodulatory agent, is a new drug that has just completed Phase III clinical trials for the treatment of both hepatitis B e antigen-positive and -negative chronic hepatitis B virus infection. The advantage of peginterferon-alpha2a in achieving sustained virologic response over nucleoside/nucleotide analogs is particularly obvious in the hepatitis B e antigen-negative group. In both studies, sustained off-treatment response is superior to the use of monotherapy with lamivudine, and concomitant use of lamivudine and pegnterferon-alpha2a does not have advantages over the use of peginterferon-alpha2a alone. These recent data put peginterferon-alpha2a as the antihepatitis B virus therapy of choice, especially in young and motivated patients with chronic hepatitis B virus infection. However, despite the superiority of peginterferon-alpha2a over currently licensed nucleoside/nucleotide analogs, more research needs to be conducted in order to find the most optimal treatment regimen in our fight against chronic hepatitis B virus infection.

Off-therapy durability of response to entecavir therapy in hepatitis B e antigen-negative chronic hepatitis B patients

The optimal duration of nucelos(t)ide analog (Nuc) treatment in hepatitis B e antigen (HBeAg)-negative patients with chronic hepatitis B virus (HBV) infection is unknown. The Asian Pacific Association for the Study of the Liver (APASL) guidelines recommend that treatment can be discontinued if undetectable HBV-DNA has been documented on three occasions ≥ 6 months apart. This study aimed to test this stopping rule in HBeAg-negative chronic hepatitis B (CHB) patients treated with entecavir (ETV). Ninety-five patients (39 cirrhosis) were treated with ETV for a median of 721 (395-1,762) days before stopping therapy and were then monitored with serum HBV DNA and alanine aminotransferase (ALT) at least every 3 months. Within 1 year after stopping ETV therapy, "clinical relapse" (an episode of ALT elevation >2 × upper limit of normal plus HBV-DNA >2,000 IU/mL) occurred in 43 (45.3%) of the 95 patients. Of the 39 cirrhosis patients, 17 (43.6%) relapsed and one (2.6%) developed decompensation. The median duration until relapse was 230 days (74.4% >6 months). Logistic regression analysis showed that baseline HBV-DNA ≤ 2 × 10(5) IU/mL was the only significant independent factor for sustained response. The 1-year relapse rate was 29% in patients with a baseline HBV DNA ≤ 2 × 10(5) IU/mL versus 53% in those with HBV DNA >2 × 10(5) IU/mL (P = 0.027). For the latter, consolidation therapy >64 weeks reduced the relapse rate to 33.3% in patients without cirrhosis.

CONCLUSION

With an overall 1-year relapse rate of 45% and 29% in those with a baseline serum HBV DNA ≤ 2 × 10(5) IU/mL, the APASL stopping rule for HBeAg-negative CHB patients with proper off-therapy monitoring is adequate even in patients with cirrhosis. Consolidation therapy >64 weeks seems more appropriate for those with higher baseline HBV DNA.

Durability after discontinuation of nucleos(t)ide therapy in chronic HBeAg negative hepatitis patients

BACKGROUND/AIMS

Relapse has been reported after stopping nucleos(t)ide (NUC) therapy in the majority of chronic HBeAg negative hepatitis patients. However, the ideal treatment duration of HBeAg negative chronic hepatitis B (CHB) is not well known. We investigated the frequency of relapse in HBeAg negative CHB patients receiving NUC therapy.

METHODS

The NUC therapy was discontinued at least 3 times undetectable level of HBV DNA leave 6 months space in 45 patients. Clinical relapse was defined as HBV DNA >2,000 IU/mL and alanine aminotransferase (ALT) or aspartate aminotransferase (AST) >2 times of upper limit of normal range. Virological relapse was defined as HBV DNA >2,000 IU/mL.

RESULTS

Clinical relapse developed in 16 (35.6%) and 24 (53.3%) patients after stopping therapy at 6 months and 12 months off therapy, respectively. Virological relapse developed 22 (48.9%) and 33 (73.3%) patients at 6 months and 12 months off therapy. The factors such as age, gender, cirrhosis, baseline AST, ALT, HBV DNA levels, treatment duration, and consolidation duration were analyzed to investigate the predictive factors associated with 1 year sustained response. Of these factors, cirrhosis (86.1% in CHB, 22.2% in LC) was significantly associated with 1 year virological relapse rate. Baseline HBV DNA and total treatment duration tended to be associated with virological relapse.

CONCLUSIONS

Virological relapse developed in the majority (73.3%) of HBeAg negative CHB patients and clinical relapse developed in the half (53.3%) of patients at 1 year off therapy. Cirrhosis may be associated with the low rate of virological relapse.

Telbivudine treatment is associated with high hepatitis B e antigen seroconversion and immune modulatory effects in chronic hepatitis B patients

Chronic hepatitis B (CHB) is characterized by an impaired immune response to hepatitis B virus. Among the nucleos(t)ides used in CHB treatment, telbivudine is associated with the highest rates of hepatitis B e antigen (HBeAg) seroconversion rates, which are similar to those observed with pegylated interferon (PegIFN). Besides direct antiviral effect, modulation of the immune system may be an additional benefit for telbivudine-treated patients. Indeed, there is much clinical data indicating an IFN-like behaviour for telbivudine in contrast to other oral nucleos(t)ides, such as high HBeAg seroconversion, similar hepatitis B surface antigen (HBsAg) decline and biphasic viral kinetics. Clinical studies, animal models and in vitro studies suggest that both the innate and adaptive immune system responses contribute to high HBeAg seroconversion during telbivudine treatment through modulation of the function and/or expression of CD4+/CD8+ T cells, Th1/Th2, Treg, PD-1/PD-L1, Th17, IL-21 and TFH. The results described in this review suggest that the antiviral effect of telbivudine may be attributable not only to direct suppression of hepatitis B virus, but also to immunoregulatory effects. Hypothetically, telbivudine shares some common signal pathways with IFN.

Hepatitis B virus genotype D predominates HBsAg-positive egyptian blood donors and is mainly associated with a negative HBeAg serostatus

OBJECTIVES

Hepatitis B virus (HBV) infection is a global health burden. In this regard, Egypt has an intermediate HBV seroprevalence. HBV is classified into ten different genotypes (A-J) with different geographic distributions. Genotype D is the most prevalent in the Middle East. Limited data are available about HBV genotyping among Egyptian blood donors, particularly in Upper Egypt. We examined the seroprevalence of HBV among 12,000 blood donors attending the blood transfusion services center in Minia Governorate, Upper Egypt.

METHODS

HBsAg and HBeAg were examined by ELISA while HBV-DNA was examined by PCR. HBV genotyping was conducted by restriction fragment length polymorphism.

RESULTS

HBsAg was detected in 237 donors (1.98%). The HBV-DNA of 50 donors with the highest HBsAg OD was examined for the HBV genotype. All 50 DNA-positive samples were of genotype D. 82% of the DNA-positive donors were males, coinciding with their representation in the cohort. ALT levels were normal in 88% of genotyped subjects, while 84% of them were HBeAg negative.

CONCLUSION

Taken together, these data indicate that HBV genotype D is the predominant genotype among HBsAg-positive blood donors in Upper Egypt and was in >80% of the subjects associated with a negative HBeAg serostatus.

Sustained responses and loss of HBsAg in HBeAg-negative patients with chronic hepatitis B who stop long-term treatment with adefovir

BACKGROUND & AIMS

Little is known about the biochemical and virological effects of stopping long-term nucleos(t)ide analogue therapy for hepatitis B e antigen (HBeAg)-negative patients with chronic hepatitis B (CHB).

METHODS

We performed a cohort observational study, following 33 HBeAg-negative patients with CHB, undetectable serum HBV DNA, and normal levels of aminotransferases after long-term (4 or 5 years) treatment with adefovir dipivoxil (ADV). All patients were followed for 5.5 years; follow-up visits included measurements of serum alanine aminotransferase (ALT), hepatitis B surface antigen (HBsAg), and HBV DNA monthly for the first 6 months and every 3-6 months thereafter. Various factors were measured at baseline, the end of treatment (EOT), and following treatment to identify those associated with clearance of HBsAg.

RESULTS

During the first few months of the postdiscontinuation period, all patients experienced virological and 25 (76%) had biochemical relapse. During the follow-up period, 18 patients (55%) who had discontinued antiviral therapy achieved sustained response (HBV DNA level <2000 IU/L, persistently normal level of ALT). Among these, 13 (72%) cleared HBsAg. Fifteen patients (45%) with virological and/or biochemical relapse were re-treated with oral antiviral agents (11 during the first 18 months and 4 after the third year), without evidence of liver decompensation; only 1 lost HBsAg (6%). Higher pretreatment and EOT levels of ALT, no previous treatment with interferon, and lower level of HBsAg at the EOT were significantly associated with HBsAg clearance based on multivariate analysis.

CONCLUSIONS

In HBeAg-negative patients with CHB, it is safe and effective to discontinue ADV therapy after 4 or 5 years; 55% of patients have sustained responses, and 39% of patients lose HBsAg.

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.

Antiviral therapies: focus on hepatitis B reverse transcriptase

Hepatitis B virus (HBV) is the etiologic agent of mankind's most serious liver disease. While the availability of a vaccine has reduced the number of new HBV infections, the vaccine does not benefit the approximately 350 million people already chronically infected by the virus. Most of the drugs approved by the FDA for the treatment of hepatitis B target the reverse transcriptase (RT or P gene product) and are nucleoside RT inhibitors (NRTIs) that suppress viral replication. However, prolonged monotherapies directed against a single target result in the emergence of viral resistance. HBV genotypic differences affect NRTI resistance, and because the reading frames of the S (surface antigen) and P genes partially overlap, genomic differences that affect the surface of the virus may also alter the viral polymerase sequence, function and drug susceptibility. The scope of this review is to assess the effects of HBV genotypic variation on the development of drug resistance to NRTIs. Some RT residues that vary among different genotypes are in the vicinity of residues that mutate and give rise to NRTI resistance. Interactions between these amino acids can help explain the effect of HBV genotype on the development of NRTI resistance during antiviral therapies, and might help in the design of improved therapeutic strategies.

A prospective clinical study in hepatitis B e antigen-negative chronic hepatitis B patients with stringent cessation criteria for adefovir

Adefovir is usually applied for therapy of chronic hepatitis B (CHB), but its effectiveness after cessation is still unknown. This study was to evaluate the effectiveness of adefovir treatment with strict cessation criteria in hepatitis B e antigen (HBeAg)-negative patients and to identify potentially important factors. One hundred forty-five HBeAg-negative CHB patients who had received adefovir treatment for at least 24 months and for whom serum hepatitis B virus (HBV) DNA had remained undetectable for at least 18 months before cessation were included. They were followed up monthly during the first four months and at 3-month or 6-month intervals thereafter. Patients with ≥10(4) copies of HBV DNA per mL were defined as relapsed. In total, 95 patients relapsed within the follow-up time, and more than 93% relapsed within 12 months after adefovir cessation. Cumulative relapse rates at months 6, 12, 24, 36, 48 and 60 were 53.8%, 61.4%, 65.5%, 65.5%, 65.5% and 65.5%, respectively. Age was the only factor associated with relapse, with lower relapse rates in younger patients shown by Cox regression analysis. HBsAg seroconversion occurred in 12 patients, and none of them relapsed during follow-up. The effectiveness of adefovir therapy does not persist in HBeAg-negative CHB patients, even when strict cessation criteria are applied, except for patients aged ≤ 25 years. HBsAg seroconversion is the ideal endpoint of adefovir treatment.

Current Nucleos(t)ide Analogue Therapy for Chronic Hepatitis B

Although the prevalence of chronic hepatitis B has decreased considerably in recent years due to widespread use of the hepatitis B virus (HBV) vaccine, its prevalence still remains high in adults, and this can place a significant burden on health care in areas with endemic HBV. Since the introduction of nucleos(t)ide analogues (NUCs), there has been marked improvement in the care of patients with chronic hepatitis B, resulting in increased survival. However, the emergence of drug resistance in patients treated with NUCs is a major concern. The number of multi-drug resistant patients is increasing, and many patients may not respond to the currently available drugs. In this review, we describe the current status of NUC therapy for antiviral-naïve and -resistant patients.

Management of chronic hepatitis B

Chronic hepatitis B continues to be a major global health burden. It accounts for a substantial impact on health care resources and finances in many parts of the world including Europe. Natural history and disease spectrum are varied, depending on when and how the infection is acquired. The chronic infective state increases patients' risk of progression to liver cirrhosis or hepatocellular carcinoma. Several treatment options are currently available, but their use depends on the stage of the patient's infection, which is influenced by both host and viral factors. The ultimate goals in hepatitis B treatment are to prevent disease progression, hepatic decompensation, hepatocellular carcinoma, and death. Patients with decompensated liver cirrhosis should be referred to specialized transplant centers in a timely manner.

Poor durability of lamivudine effectiveness despite stringent cessation criteria: a prospective clinical study in hepatitis B e antigen-negative chronic hepatitis B patients

BACKGROUND AND AIMS

Lamivudine, a nucleoside analog, is commonly used for treatment of chronic hepatitis B (CHB) but its durability of effectiveness after withdrawal is still uncertain. This study was designed to assess the durability of lamivudine treatment with stringent cessation criteria in hepatitis B e antigen (HBeAg)-negative patients and to explore potential predictive factors.

METHODS

Sixty one HBeAg-negative CHB patients who had received lamivudine for at least 24 months and had maintained undetectable serum hepatitis B virus (HBV) DNA plus normal alanine aminotransferase for ≥ 18 months before withdrawal were included. They were followed up monthly during the first 4 months and at 3-month or 6-month intervals thereafter. Relapse was defined as serum HBV DNA ≥ 10(4) copies/mL.

RESULTS

Thirty one of 61 patients relapsed during follow-up, over 90% occurred within 18 months after lamivudine withdrawal. Cumulative relapse rates at months 6, 12, 24, 36, 48 and 60 were 26.2%, 43.6%, 49.7%, 52.1%, 56.1% and 56.1%, respectively. Cox regression revealed that age was the only predictive factor for relapse, with lower relapse rates found in younger patients. Hepatitis B surface antigen (HBsAg) turned negative in eight patients, and none of them relapsed during follow-up.

CONCLUSION

Effectiveness of lamivudine treatment is not durable in HBeAg-negative CHB patients even when stringent cessation criteria are adopted, with the exception of patients aged ≤ 20 years. The ideal end point of lamivudine treatment is clearance of serum HBsAg.

De novo combination of lamivudine and adefovir versus entecavir monotherapy for the treatment of naïve HBeAg-negative chronic hepatitis B patients

PURPOSE

Either combination treatment or monotherapy using agents with a high genetic barrier are recommended for hepatitis B e antigen (HBeAg)-negative chronic hepatitis B (CHB). The aim of this study was to compare effect of naïve HBeAg-negative CHB patients with either de novo combination of lamivudine (LAM) and adefovir dipivoxil (ADV) or entecavir (ETV) monotherapy.

METHODS

HBeAg-negative CHB patients (n = 71) with ALT levels between 2 and 10 times the upper normal limit and HBV DNA levels >10(4) copies/mL were enrolled. Patients were treated with either LAM 100 mg plus ADV 10 mg per day (n = 31) or ETV 0.5 mg per day (n = 40) for 48 weeks.

RESULTS

The average reduction in HBV DNA level compared with baseline were 5.16 ± 1.69 log in the LAM + ADV group and 5.36 ± 1.70 log in the ETV group by week 48 (P = 0.624). The virological response (VR) rates were 80.65 and 77.5%, the biochemical response (BR) rates were 93.55 and 90.00% at week 48 in the LAM + ADV and ETV groups, respectively. There was no significant difference in the VR and BR between the two groups. During the 48-week treatment period, virological breakthrough and serious side effects were not noted in any patient.

CONCLUSIONS

Both LAM + ADV combination therapy and ETV monotherapy are effective in naïve HBeAg-negative CHB patients, but further studies are needed to obtain long-term results.

Review of hepatitis B therapeutics

Currently, there are 7 approved therapies for chronic hepatitis B virus (HBV) infection, an increase from just 3 agents 5 years ago. This review will focus on the pharmacology, potency, and adverse events associated with immunomodulatory agents and nucleos(t)ide analogues, with an emphasis on targets of therapy within the HBV life cycle. We will also offer guidelines for the use of available anti-HBV agents and review the emerging challenges in hepatitis B management, including HBV drug resistance, its management, and the potential role of combination therapy.

Peginterferon therapy for HBeAg-negative chronic hepatitis B: less than meets the eye

Pegylated interferon (PEG IFN) has been recommended as a first-line therapy for hepatitis B e antigen (HBeAg)-negative chronic hepatitis B; however, data supporting this recommendation are derived from a single randomized controlled trial. In this issue of the Journal, Rijckborst et al. report the results of a second randomized controlled PEG IFN trial in 138 HBeAg-negative patients. The trial was undertaken to test the efficacy of adding ribavirin to PEG IFN; however, the results were unequivocal in concluding that adding ribavirin was not effective. Moreover, the efficacy of PEG IFN for these HBeAg-negative subjects was disappointing; only 7.5% of the study cohort had undetectable hepatitis B virus DNA (<400 copies/ml) 24 weeks after a 48-week course of therapy, and none lost hepatitis B surface antigen. This study challenges the value and limits the appeal of PEG IFN therapy for HBeAg-negative chronic hepatitis B.

Antiviral therapy for chronic hepatitis B

The goal of antiviral therapy for chronic hepatitis B is to prevent the development of cirrhosis and hepatocellular carcinoma. End points, including viral suppression, alanine aminotransferase normalization, hepatitis B e antigen loss, hepatitis B surface antigen loss, and improvement in liver histology, are used to determine treatment success. Treatment is based on hepatitis B virus (HBV) replication status and stage of liver disease, modulated by the age of the patient, hepatitis B e antigen (HBeAg) status and patient preference. Seven therapies are approved, including two formulations of interferon and five orally administered nucleos(t)ide analogs. These therapies are effective in suppressing HBV replication and have also been shown to prevent disease progression.

Clinical efficacy of a 24-months course of lamivudine therapy in patients with HBeAg negative chronic hepatitis B: a long-term prospective study

The optimal duration of oral nucleos(t)ide analogue therapy for HBeAg negative chronic hepatitis B (CHB) has not been defined. The aim of this study was to investigate the clinical efficacy of 24-months course of lamivudine therapy in patients with HBeAg negative CHB in Korea. A total of 50 Korean patients with HBeAg negative CHB were prospectively enrolled. The patients received 100 mg/day of lamivudine orally for 24 months. Patients who showed complete response at 24 months to lamivudine therapy stopped treatment, and regular follow-up was done thereafter. The mean follow-up duration after cessation of therapy was 40.8+/-22.7 (range 12-96) months. The complete response rate at months 12 and 24 were 86.0% (43/50) and 86.0% (43/50), respectively, and the clinical breakthrough at months 12 and 24 were 4.0% (2/50) and 14.0% (7/50), respectively. The expected durability of responses at months 12, 24, and 36 after cessation of lamivudine therapy in 43 complete responders was 79.1%, 64.0%, and 56.9%, respectively. In conclusion, a 24-months course of lamivudine therapy shows high end-treatment response rate and substantial durability of initial response after cessation of therapy in HBeAg negative CHB patients in Korea.

Antiviral treatment of chronic hepatitis B virus (HBV) infections

While 25 compounds have been formally licensed for the treatment of HIV infection (AIDS), only seven licensed products are currently available for the treatment of chronic hepatitis B virus (HBV) infection: interferon-α, pegylated interferon-α, lamivudine, adefovir (dipivoxil), entecavir, telbivudine and tenofovir (disoproxil fumarate). In contrast to the treatment of HIV infections where the individual drugs are routinely used in combination, for the treatment of chronic HBV infection the individual drugs are generally used in monotherapy. In principle, combination drug therapy should allow reducing the likelihood of drug-resistant development.