Relapse of hepatitis B in HBeAg-negative chronic hepatitis B patients who discontinued successful entecavir treatment: the case for continuous antiviral therapy

Developments in pharmacotherapeutic agents for hepatitis B - how close are we to a functional cure?

INTRODUCTION

Hepatitis B virus (HBV) remains a public health concern given its global prevalence and potential complications including hepatocellular carcinoma (HCC). Current therapies, including nucleos(t)ide analogs (NA) and interferons (IFN), are effective in chronic treatment of HBV but rarely provide a functional cure due to inadequate host response and the presence of viral DNA. Therefore, novel therapies that enhance the innate immune response while suppressing DNA transcription may provide definitive treatment of HBV.

AREAS COVERED

In this review, the authors provide a brief overview of commonly used agents and their efficacy in treatment of HBV. Newer therapies with direct antiviral agents such as bepirovirsen (antisense oligonucleotide (ASO)) and entry inhibitors such as bulevirtide have shown efficacy in reducing viral load but demonstrate further reductions in conjunction with immune modulators such as therapeutic vaccines.

EXPERT OPINION

Combination therapy is far superior to monotherapy alone, necessitating the need for both immunomodulators and direct antiviral agents in chronic treatment of HBV. Therapies that target covalently closed circular (cccDNA) with immunomodulators like therapeutic vaccines have shown promising results and may ultimately achieve functional cure. However, therapies need to be evaluated in the context of the patient, considering both financial and socioeconomic factors.

The long and stumble way to find potential active compounds from plants for defeating hepatitis B and C: review

Hepatitis is a liver illness caused by virus such as hepatitis A virus, hepatitis B virus and hepatitis C virus. Hepatitis B and C are considerably more usual and induce more cirrhosis and dead worldwide than hepatitis A. Although drugs that are currently often used in the medication of hepatitis B and C, the finding of recent drug from various resources including herbal has been intensively developed. Therefore, the purpose of this review is to consider the possibility of plant’s compounds as anti-HBV and anti-HCV. From the results of a review of several articles, several plant’s compound have shown effectiveness againts HBV and HCV by in silico, in vitro and in vivo studies. In conclusion, several plant’s active compounds are possibility to be developed as anti-hepatitis B and C.

Transaminase Elevations during Treatment of Chronic Hepatitis B Infection: Safety Considerations and Role in Achieving Functional Cure

While current therapies for chronic HBV infection work well to control viremia and stop the progression of liver disease, the preferred outcome of therapy is the restoration of immune control of HBV infection, allowing therapy to be removed while maintaining effective suppression of infection and reversal of liver damage. This “functional cure” of chronic HBV infection is characterized by the absence of detectable viremia (HBV DNA) and antigenemia (HBsAg) and normal liver function and is the goal of new therapies in development. Functional cure requires removal of the ability of infected cells in the liver to produce the hepatitis B surface antigen. The increased observation of transaminase elevations with new therapies makes understanding the safety and therapeutic impact of these flares an increasingly important issue. This review examines the factors driving the appearance of transaminase elevations during therapy of chronic HBV infection and the interplay of these factors in assessing the safety and beneficial nature of these flares.

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.

Bayesian Network Meta-Analysis for Assessing Adverse Effects of Anti-hepatitis B Drugs

BACKGROUND AND OBJECTIVE

Oral nucleoside/nucleotide analogues (NAs) have been advocated for chronic hepatitis B (CHB) treatment with good efficacy. However, less attention has been put on their adverse events. Therefore, a Bayesian network meta-analysis (NMA) was performed to evaluate the relative safety of five NAs (lamivudine, adefovir dipivoxil, entecavir, telbivudine, and tenofovir disoproxil fumarate) in CHB treatment among adults.

METHODS

Eligible randomized clinical trials (RCTs) and prospective cohort studies were systematically and thoroughly searched until May 1, 2019. Poisson-prior-based Bayesian NMA was performed to synthesize both direct and indirect evidence with reporting hazard ratios (HRs) and 95% credible intervals (CrIs) for serious adverse events (SAEs) and hepatic/renal impairments.

RESULTS

Thirty-three RCTs and 11 prospective cohort studies were identified. As to SAEs, no statistically significant difference was found of any comparison among five NAs. In terms of hepatotoxicity, lamivudine was safer than telbivudine (HR 0.45; 95% CrI 0.21, 0.85), and entecavir increased the risk by 102% (entecavir vs lamivudine: HR 2.02; 95% CrI 1.19, 3.27).

CONCLUSIONS

The findings from this large NMA could influence clinical practice, and the methodological framework of this study could provide evidence-based support to analyze sparse safety data in the field.

Varying 10-year off-treatment responses to nucleos(t)ide analogues in patients with chronic hepatitis B according to their pretreatment hepatitis B e antigen status

OBJECTIVE

To evaluate the long-term durability and efficacy of nucleos(t)ide analogues (NAs) and to determine the related factors for virological relapse in chronic hepatitis B (CHB) patients.

METHODS

CHB patients who fulfilled the criteria for discontinuing NAs therapy in accordance with the published guidelines were included in the study from December 2001. Virological relapse was defined as serum hepatitis virus B (HBV) DNA >10⁴ copies/mL twice at least 2 weeks apart.

RESULTS

A total of 223 CHB patients were enrolled at the time their NAs therapy was discontinued. The 10-year cumulative relapse rate (CRR) in hepatitis B e antigen (HBeAg)-positive patients was statistically lower than that in HBeAg-negative patients (30.9% vs 62.3%, P < 0.001). In the HBeAg-positive group, Cox regression analysis showed that age at cessation (hazard ratio [HR] 1.067, P < 0.001), consolidation therapy (HR 0.958, P = 0.021), and time to HBeAg seroconversion (HR 0.943, P = 0.019) were predictors for relapse. In the HBeAg-negative group, age at cessation (HR 1.040, P = 0.004) and time to HBV DNA negativity (HR 1.246, P = 0.010) were potential predictors for virological relapse.

CONCLUSIONS

The off-treatment responses to NAs differ in CHB patients with different pretreatment HBeAg status. NA withdrawal is generally safe and feasible in young patients with CHB. Long consolidation periods should be preferred in HBeAg-positive patients to achieve better durability. Benefits of cessation of NAs do not last long in HBeAg-negative CHB patients.

Efficacy and safety of entecavir versus lamivudine over 5 years of treatment: A randomized controlled trial in Korean patients with hepatitis B e antigen-negative chronic hepatitis B

BACKGROUND/AIMS

Long-term data on antiviral therapy in Korean patients with hepatitis B e antigen (HBeAg)-negative chronic hepatitis B (CHB) are limited. This study evaluated the efficacy and safety of entecavir (ETV) and lamivudine (LAM) over 240 weeks.

METHODS

Treatment-naive patients with HBeAg-negative CHB were randomized to receive ETV 0.5 mg/day or LAM 100 mg/day during the 96 week double-blind phase, followed by open-label treatment through week 240. The primary endpoint was the proportion of patients with virologic response (VR; hepatitis B virus [HBV] DNA<300 copies/mL) at week 24. Secondary objectives included alanine aminotransferase (ALT) normalization and emergence of ETV resistance (week 96), VR and log reduction in HBV DNA levels (week 240), and safety evaluation.

RESULTS

In total, 120 patients (>16 years old) were included (ETV, n=56; LAM, n=64). Baseline characteristics were comparable between the two groups. A significantly higher proportion of ETV-treated patients achieved VR compared to LAM at week 24 (92.9% vs. 67.2%, P=0.0006), week 96 (94.6% vs. 48.4%, P<0.0001), and week 240 (95.0% vs. 47.6%, P<0.0001). At week 96, ALT normalization was observed in 87.5% and 51.6% of ETV and LAM patients, respectively (P<0.0001). Virologic breakthrough occurred in one patient (1.8%) receiving ETV and 26 patients (42.6%) receiving LAM (P<0.0001) up to week 96. Emergence of resistance to ETV was not detected. The incidence of serious adverse events was low and unrelated to the study medications.

CONCLUSIONS

Long-term ETV treatment was superior to LAM, with a significantly higher proportion of patients achieving VR. Both treatments were well tolerated.

Effect of switching from treatment with nucleos(t)ide analogs to pegylated interferon α-2a on virological and serological responses in chronic hepatitis B patients

AIM

To investigate the efficacy of switching to pegylated interferon-α-2a (PegIFNα-2a) treatment in nucleos(t)ide analog (NA)-treated chronic hepatitis B (CHB) responder patients.

METHODS

A 48-wk prospective and retrospective treatment trial of NA-treated CHB patients who had received entecavir (ETV) for at least 48 wk and had serum hepatitis B virus (HBV)-DNA < 500 IU/mL, serum hepatitis B envelope antigen (HBeAg) < 100 S/CO, serum alanine aminotransferase, and aspartate aminotransferase levels < 2 × the upper limit of normal of 40 IU/L was performed. The effects on virological and serological responses and adverse reactions to 0.5 mg daily ETV for 48 wk vs switching to PegIFNα-2a were compared. Forty-four patients were randomized to be switched from NA treatment to the PegIFNα-2a group, and 44 patients were simultaneously randomized to the ETV group.

RESULTS

After 48 wk of therapy, the decrease in hepatitis B surface antigen (HBsAg) levels was greater in the PegIFNα-2a group than in the ETV group (3.1340 log₁₀ IU/mL vs 3.6950 log₁₀ IU/mL, P = 0.00). Seven patients who were anti-HBs-positive at baseline achieved HBsAg loss when switched to PegIFNα-2a (15.91% vs 0%, P = 0.018). The HBeAg serological conversion rate was higher in the PegIFNα-2a group than in the ETV group; however, the difference was not significant because of the small sample sizes (34.38% vs 21.88%, P = 0.232). In the PegIFNα-2a group, patients with HBsAg levels < 1500 IU/mL at baseline had higher HBeAg seroconversion and HBsAg loss rates at week 48 than those with HBsAg levels ≥ 1500 IU/mL (HBeAg seroconversion: 17.86% vs 62.5%, P = 0.007; HBsAg loss: 41.67% vs 6.25%, P = 0.016). Moreover, patients with HBsAg levels < 1500 IU/mL at week 24 had higher HBsAg loss rates after therapy than those with HBsAg levels ≥ 1500 IU/mL (36.84% vs 0%, P = 0.004). However, there were no statistically significant differences in HBeAg seroconversion rates (47.06% vs 25.93%, P = 0.266).

CONCLUSION

NA-treated CHB patients switched to sequential PegIFNα-2a achieved highly potent treatment termination safely.

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.

Efficacy of PEGylated Interferon in Treatment-Experienced Chinese Patients With HBeAg Positive Chronic Hepatitis B

BACKGROUND

After treatment cessation, a high prevalence of relapse was reported in chronic hepatitis B (CHB) patients in China, especially in nucleot(s)ide analogues (NUCs)-experienced patients. Re-treatment for these patients remains unsolved.

OBJECTIVES

This study aims to evaluate the efficacy of PEGylated interferon in HBeAg positive patients with exposure to antiviral therapy.

PATIENTS AND METHODS

A total of 55 treatment-experienced, HBeAg positive Chinese patients were enrolled in this study. Of these patients, 33 were NUCs-experienced and 22 were interferon-experienced. PEGylated interferon was administered to 34 patients; and 21 patients were retreated with conventional interferon.

RESULTS

Of the 34 treatment-experienced patients who received PEGylated interferon, 52.9% achieved virologic response, and 41.2% achieved HBeAg loss and seroconversion. Patients who were treated with PEGylated interferon for 48 weeks achieved higher virologic response (80%); HBeAg loss (60%); HBeAg seroconversion (60%); and HBsAg loss (5%) than patients treated for 24 weeks with PEGylated interferon. Their responses were also higher than those who were treated with conventional interferon. HBeAg seroconversion in treatment-experienced patients was independently associated with 48-week PEGylated interferon therapy duration.

CONCLUSIONS

PEGylated interferon was effective in treatment-experienced patients with HBeAg positive CHB, and showed higher rates of virological response, HBeAg loss, and seroconversion. The results provide important information regarding the role of re-treatment with PEGylated interferon in treatment-experienced HBeAg positive patients.

Extended duration versus standard duration of peginterferon alfa-2a in treatment of chronic hepatitis B: A systematic review and meta-analysis

In the last decade, PEG-IFNa-2a has been widely used in the treatment of chronic hepatitis B (CHB). The current standard duration is 48 weeks; however, several studies based on small sample sizes have indicated that treatment extended beyond 48 weeks improved clinical outcomes than standard 48 weeks of therapy. Therefore, we performed a meta-analysis to compare the efficacy and safety of extended duration versus standard duration treatment with PEG-IFNa-2a monotherapy for patients with CHB. Four studies comprising of 350 patients were included in our study. Our analysis showed that extended treatment resulted in a higher HBsAg clearance rate compared with the standard treatment at the end of treatment, 24 and 48 weeks post-treatment [odds ratio (OR)=2.45, 95% confidence intervals (CI) (1.17-5.11), P=0.02; OR=3.17, 95% CI (1.62-6.21), P<0.01; OR=5.02, 95% CI (1.63-15.45), P<0.01, respectively]. Higher HBeAg seroconversion rates were also obtained in the extended treatment group than the standard treatment group at the end of treatment and 48 weeks post-treatment [OR=2.09, 95% CI (1.10-3.98), P=0.02, and OR=2.67, 95% CI (1.39-5.13), P<0.01, respectively]. In addition, extended treatment was superior to standard treatment in HBV-DNA inhibition rate at 48 weeks post-treatment [OR=3.15, 95% CI (1.51-6.57), P<0.01]. Therefore, extended treatment with PEG-IFNa-2a beyond 48 weeks may be a promising strategy to achieve higher rates of sustained HBV-DNA inhibition, HBeAg seroconversion and HBsAg clearance off-therapy for patients with CHB.

Entecavir safety and effectiveness in a national cohort of treatment-naïve chronic hepatitis B patients in the US - the ENUMERATE study

BACKGROUND

Entecavir (ETV) has been shown to be safe and efficacious in randomised controlled trials in highly selected patients with hepatitis B virus (HBV) infection.

AIM

To determine the safety and effectiveness of ETV in 'real-world' HBV patients in the United States (US).

METHODS

Treatment-naïve HBV patients ≥18 years old who received ETV for ≥12 months between 2005 and 2013 were included in a retrospective, cohort study. Rates of ALT normalisation, undetectable HBV DNA, HBeAg and HBsAg loss/seroconversion, adverse events (AE) and clinical outcomes were evaluated.

RESULTS

Of 841 patients, 658 [65% male, 83% Asian; median age 47 years] met the inclusion criteria. 36% were HBeAg+ and 9.3% cirrhotic. 89% had abnormal ALT. Baseline median HBV DNA was 5.8 log 10 IU/mL. Median duration of ETV treatment was 4 years. Rates of ALT normalisation at 1, 3 and 5 years were 37.2%, 48.7% and 56.2% in HBeAg+ and 39.6%, 46.8% and 55.6% in HBeAg- patients. HBV DNA was undetectable at 1, 3 and 5 years in 34.6%, 64.7% and 84.6% in HBeAg+ patients, and 81.9%, 90.3% and 96.2% in HBeAg patients. Five-year cumulative probability of HBeAg loss and seroconversion was 46% and 33.7% and HBsAg loss was 4.6%. ETV was discontinued due to adverse events in 1.2% of patients. Hepatic decompensation occurred in 0.8%, liver cancer in 2.7% and death in 0.6%.

CONCLUSION

Entecavir treatment was safe in a large cohort of US patients, but ALT normalisation and hepatitis B virus DNA suppression rates were lower than previously reported in clinical trials.

Risk Factors for Renal Functional Decline in Chronic Hepatitis B Patients Receiving Oral Antiviral Agents

Renal functional decline that is frequently seen during chronic hepatitis B (CHB) treatment can exert adverse effects on overall prognosis. It, however, is difficult to distinguish vulnerable patients who may experience renal dysfunction because most previous CHB studies were conducted in relatively healthy individuals. In this retrospective observational study, renal functional decline in CHB patients receiving oral antiviral agents for more than 6 months was analyzed and risk factors of chronic kidney disease (CKD) progression were determined. Renal functional decline was defined when the estimated glomerular filtration rate (eGFR) decreased by more than 25% from baseline and rapid CKD progression was defined as eGFR decreased by more than 5 mL/min/1.73 m2/y among patients who experienced renal functional decline. A total of 4178 patients were followed up for a median 23 months. Antiviral agents included lamivudine (17.0%), adefovir (3.7%), entecavir (70.4%), telbivudine (0.6%), tenofovir (4.0%), or clevudine (4.3%). Renal functional decline occurred in 706 (16.9%) patients. Based on multivariate Cox regression analysis, age, hypertension, diabetes, history of liver or kidney transplantation, underlying underlying CKD, and simultaneous administration of diuretics increased the hazard ratio for renal functional decline; however, clevudine reduced risk. The eGFR significantly increased over time in patients receiving telbivudine or clevudine compared with lamivudine. Among the 3175 patients followed up for more than 1 year, 407 (12.8%) patients experienced rapid CKD progression. Patients with rapid CKD progression showed lower serum albumin, higher total bilirubin, and prolonged prothrombin time compared with patients with stable renal function, but hepatitis B envelope antigen positivity and hepatitis B virus deoxyribonucleic acid level did not differ between the control and rapid CKD progression groups. Age, diabetes, kidney transplantation, underlying CKD, and simultaneous administration of diuretics were identified as risk factors for rapid CKD progression, and clevudine showed a beneficial effect. Age, hypertension, diabetes, liver or kidney transplantation, underlying CKD, and diuretics were identified as risk factors for renal functional decline. This study suggests that close monitoring of renal function and adequate management are required for CHB patients receiving antiviral agents with these risk factors.

Cost-Effectiveness and Cost Thresholds of Generic and Brand Drugs in a National Chronic Hepatitis B Treatment Program in China

Chronic liver disease and liver cancer associated with chronic hepatitis B (CHB) are leading causes of death among adults in China. Although newborn hepatitis B immunization has successfully reduced the prevalence of CHB in children, about 100 million Chinese adults remain chronically infected. If left unmanaged, 15–25% will die from liver cancer or liver cirrhosis. Antiviral treatment is not necessary for all patients with CHB, but when it is indicated, good response to treatment would prevent disease progression and reduce disease mortality and morbidity, and costly complications. The aim of this study is to analyze the cost-effectiveness of generic and brand antiviral drugs for CHB treatment in China, and assessing various thresholds at which a highly potent, low resistance antiviral drug would be cost-saving and/or cost-effective to introduce in a national treatment program. We developed a Markov simulation model of disease progression using effectiveness and cost data from the medical literature. We measured life-time costs, quality adjusted life years (QALYs), incremental cost-effectiveness ratios (ICERs), and clinical outcomes. The no treatment strategy incurred the highest health care costs ($12,932-$25,293) per patient, and the worst health outcomes, compared to the antiviral treatment strategies. Monotherapy with either entecavir or tenofovir yielded the most QALYs (14.10–19.02) for both HBeAg-positive and negative patients, with or without cirrhosis. Threshold analysis showed entercavir or tenofovir treatment would be cost saving if the drug price is $32–75 (195–460 RMB) per month, highly cost-effective at $62–110 (379–670 RMB) per month and cost-effective at $63–120 (384–734 RMB) per month. This study can support policy decisions regarding the implementation of a national health program for chronic hepatitis B treatment in China at the population level.

Application of CRISPR/Cas9 Technology to HBV

More than 240 million people around the world are chronically infected with hepatitis B virus (HBV). Nucleos(t)ide analogs and interferon are the only two families of drugs to treat HBV currently. However, none of these anti-virals directly target the stable nuclear covalently closed circular DNA (cccDNA), which acts as a transcription template for viral mRNA and pre-genomic RNA synthesis and secures virus persistence. Thus, the fact that only a small number of patients treated achieve sustained viral response (SVR) or cure, highlights the need for new therapies against HBV. The clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 gene editing system can specifically target the conserved regions of the HBV genome. This results in robust viral suppression and provides a promising tool for eradicating the virus. In this review, we discuss the function and application of the CRISPR/Cas9 system as a novel therapy for HBV.

Efficacy and safety of tenofovir in nucleos(t)ide-naïve patients with genotype C chronic hepatitis B in real-life practice

BACKGROUND

Tenofovir disoproxil fumarate (TDF) has demonstrated potent antiviral activity against hepatitis B virus (HBV) in clinical trials. Although its efficacy has been demonstrated in Caucasian populations, TDF has not previously been studied in Korean patients who present the predominance of HBV genotype C and of vertical or perinatal transmission.

OBJECTIVE

The aim of this study was to evaluate the efficacy of TDF in Korean chronic hepatitis B (CHB) patients in real-life practice, and to determine the clinical variables that contribute to virologic response.

SETTING

Large academic medical center in Korea.

METHOD

We retrospectively investigated the efficacy of TDF treatment for more than 6 months in 151 nucleos(t)ide-naïve CHB patients.

MAIN OUTCOME MEASURE

The primary endpoint was a virologic response (VR), defined as an HBV DNA level of <12 IU/mL. Secondary endpoints were rates of alanine aminotransaminase (ALT) normalization, hepatitis B e antigen (HBeAg) seroconversion, virologic breakthrough, and safety.

RESULTS

All patients were the genotype C2. The median duration of TDF treatment was 13 months (range 7-18 months). Ninety-two (61.0 %) patients were HBeAg positive. The mean pre-treatment HBV DNA level was 6.34 ± 1.42 log10 IU/mL. Among the 131 patients with elevated ALT levels at baseline, 128 (97.7 %) patients achieved ALT normalization during TDF treatment. VR was achieved in 97 (64.2 %) patients. The cumulative rates of VR at 6, 9, 12, and 18 months were 47.0, 59.4, 67.9, and 69.3 %, respectively. Among the 92 HBeAg-positive patients, 14 (15.2 %) patients achieved HBeAg seroconversion. In multivariate analysis, absolute HBV DNA levels at baseline (P < 0.001; OR 0.529; 95 % CI 0.560-0.744) and HBeAg positivity (P = 0.015; OR 0.731; 95 % CI 0.615-0.869) were significantly associated with VR. Virologic breakthrough was observed in four patients. These four patients had poor adherence to TDF. Most of the adverse events were mild in severity. No significant changes were observed in serum creatinine and phosphorus levels.

CONCLUSIONS

TDF was effective and well tolerated in Korean genotype C CHB patients in real life practice, consistent with larger registration trials. The absolute HBV DNA levels at baseline and HBeAg positivity were significantly associated with VR.

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.

Tenofovir discontinuation after long-term viral suppression in HBeAg negative chronic hepatitis B. Can HBsAg levels be useful?

BACKGROUND

Recent studies have shown that antiviral treatment discontinuation is safe and associated with virologic remission in HBeAg-negative patients. However, the period of viral suppression and follow-up in these studies was relatively short.

OBJECTIVES

To investigate whether continuous viral suppression with tenofovir disoproxil fumarate for more than 7 years is associated with HBsAg loss and sustained response after treatment discontinuation and receiving a full course of hepatitis B vaccination.

STUDY DESIGN

Patients with HBeAg-negative chronic HBV infection and more than 7 years of persistent viral suppression with tenofovir therapy were selected for treatment discontinuation and HBV vaccination. Follow-up with monthly ALT, HBV-DNA, and HBsAg determinations lasted 72 weeks. In patients with viral relapse, the viral quasispecies in the overlapping reverse transcriptase and small surface protein regions was analysed by ultra-deep pyrosequencing.

RESULTS

Eight of 17 HBeAg-negative patients accepted tenofovir discontinuation: 5 patients achieved sustained response (persistent HBV-DNA levels <2000IU/mL and normal ALT) despite an initial virologic relapse, one lost HBsAg, and two needed re-treatment. All patients with an on-treatment HBsAg level decline >5000IU/mL achieved sustained response. Patients with HBsAg level <100IU/mL during an ALT flare after antiviral discontinuation achieved sustained response. Significant changes were seen in the composition of the HBV quasispecies, and half the patients showed changes in HBV genotype.

CONCLUSIONS

Even though the majority of patients presented an initial relapse with selection of HBV variants, most achieved sustained response. Changes in HBsAg levels on and off treatment may be useful for predicting the likelihood of virologic remission.

Chronic hepatitis B: Virology, natural history, current management and a glimpse at future opportunities

The host immune system plays an important role in chronic hepatitis B (CHB), both in viral clearance and hepatocellular damage. Advances in our understanding of the natural history of the disease have led to redefining the major phases of infection, with the "high replicative, low inflammatory" phase now replacing what was formerly termed the "immune tolerant" phase, and the "nonreplicative phase" replacing what was formerly termed the "inactive carrier" phase. As opposed to the earlier view that HBV establishes chronic infection by exploiting the immaturity of the neonate's immune system, new findings on trained immunity show that the host is already somewhat "matured" following birth, and is actually very capable of responding immunologically, potentially altering future hepatitis B treatment strategies. While existing therapies are effective in reducing viral load and necroinflammation, often restoring the patient to near-normal health, they do not lead to a cure except in very rare cases and, in many patients, viremia rebounds after cessation of treatment. Researchers are now challenged to devise therapies that will eliminate infection, with a particular focus on eliminating the persistence of viral cccDNA in the nuclei of hepatocytes. In the context of chronic hepatitis B, new definitions of 'cure' are emerging, such as 'functional' and 'virological' cure, defined by stable off-therapy suppression of viremia and antigenemia, and the normalization of serum ALT and other liver-related laboratory tests. Continued advances in the understanding of the complex biology of chronic hepatitis B have resulted in the development of new, experimental therapies targeting viral and host factors and pathways previously not accessible to therapy, approaches which may lead to virological cures in the near term and functional cures upon long term follow-up. This article forms part of a symposium in Antiviral Research on "An unfinished story: from the discovery of the Australia antigen to the development of new curative therapies for hepatitis B."

Treatment cessation of entecavir in Asian patients with hepatitis B e antigen negative chronic hepatitis B: a multicentre prospective study

BACKGROUND AND OBJECTIVE

The off-treatment durability of nucleos(t)ide analogue therapy in Asian hepatitis B e antigen (HBeAg) negative chronic hepatitis B (CHB) and the role of hepatitis B surface antigen (HBsAg) levels in predicting off-treatment durability has not been well investigated.

METHODS

Following Asia-Pacific Association for the Study of the Liver guidelines, entecavir was stopped in Asian HBeAg negative patients treated for ≥ 2 years with undetectable HBV DNA levels on ≥ 3 separate occasions 6 months apart before treatment cessation. HBsAg and HBV DNA levels were prospectively monitored every 6-12 weeks for 48 weeks. Entecavir was restarted if there was virologic relapse (defined as HBV DNA >2000IU/mL).

RESULT

184 patients (mean age 53.9 years, 67.9% male) were recruited. The cumulative rate of virologic relapse at 24 and 48 weeks was 74.2% and 91.4%, respectively. The median HBV DNA level at virologic relapse was 11000 (range 2115 to >1.98×10(8)) IU/mL. 42 (25.8%) patients had elevated alanine aminotransferase (median level 97 U/L, range 37-1058 U/L) during virologic relapse. Mean rate of off-treatment HBsAg decline was 0.018 (± 0.456) log IU/mL/year. No patients cleared HBsAg. There was no correlation between off-treatment serial HBsAg and HBV DNA levels (r=-0.026, p=0.541). HBsAg levels at the time of entecavir commencement, entecavir cessation and the subsequent rate of HBsAg reduction were not associated with virologic relapse (all p>0.05).

CONCLUSIONS

Entecavir cessation in Asian HBeAg negative CHB resulted in high rates of virologic relapse, suggesting nucleos(t)ide analogue therapy should be continued indefinitely until the recognised treatment endpoint of HBsAg seroclearance.

Entecavir has high efficacy and safety in white patients with chronic hepatitis B and comorbidities

OBJECTIVES

The aim of this study was to evaluate the efficacy and safety of entecavir monotherapy in nucleos(t)ide-naive chronic hepatitis B patients and to analyse the influence of the comorbidity burden on therapy outcome.

METHODS

We retrospectively analysed data from 237 nucleos(t)ide-naive chronic hepatitis B white patients treated with entecavir (0.5 mg/day) at 23 Spanish centres. For the efficacy and safety analyses, patients were grouped according to their baseline comorbidities.

RESULTS

The mean age of the cohort was 43 years (range: 19-82 years); 73% were male, 83% were white, and 33% were hepatitis B e antigen (HBeAg) positive. At baseline, the median hepatitis B virus DNA level was 6.20 log10 IU/ml. Of the patients, 18% had cirrhosis, 9.7% had diabetes, 16.3% had hypertension, and 15.7% had obesity; 13.4% of patients had more than one comorbid condition. Virological and biochemical responses at month 36 were obtained independently of the patients' baseline comorbid condition. Of 10 HBeAg-positive patients who discontinued treatment after HBeAg seroconversion, those who had not also cleared HBsAg (six) experienced virological recurrence in a median 5.6 months. There were no treatment discontinuations due to adverse events. Three patients were diagnosed with hepatocellular carcinoma at months 12, 30 and 54, and six experienced hepatic decompensation during follow-up. The median serum creatinine levels did not increase after 36 months of treatment, even in patients with comorbidities.

CONCLUSION

Entecavir is safe, well tolerated, and highly effective, even in patients with comorbid condition(s). Discontinuation of treatment in patients who have not been cleared of HBsAg may lead to virological recurrence.

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.

Practical approach in hepatitis B e antigen-negative individuals to identify treatment candidates

The natural history of chronic hepatitis B is characterized by different phases of infection, and patients may evolve from one phase to another or may revert to a previous phase. The hepatitis B e antigen (HBeAg)-negative form is the predominant infection worldwide, which consists of individuals with a range of viral replication and liver disease severity. Although alanine transaminase (ALT) remains the most accessible test available to clinicians for monitoring the liver disease status, further evaluations are required for some patients to assess if treatment is warranted. Guidance from practice guidelines together with thorough investigations and classifications of patients ensure recognition of who needs which level of care. This article aims to assist physicians in the assessment of HBeAg-negative individuals using liver biopsy or non-invasive tools such as hepatitis B s antigen quantification and transient elastography in addition to ALT and hepatitis B virus DNA, to identify who will remain stable, who will reactivate or at risk of disease progression hence will benefit from timely initiation of anti-viral 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.

Population health impact and cost-effectiveness of monitoring inactive chronic hepatitis B and treating eligible patients in Shanghai, China

Inactive chronic hepatitis B (CHB) carriers make up the largest group of hepatitis B virus-infected patients, and China bears the largest total CHB burden of any country. We therefore assessed the population health impact and cost-effectiveness of a strategy of lifelong monitoring for inactive CHB and treatment of eligible patients in Shanghai, China. We used a computer simulation model to project health outcomes among a population cohort of CHB based on age-specific prevalence of hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg), and cirrhosis. Using a Markov model we simulated patients' progression through a discrete series of health states, and compared current practice to a monitor and treat (M&T) strategy. We measured lifetime costs and quality-adjusted life years (QALYs) (both discounted at 3% per year), incremental cost-effectiveness ratios (ICERs), and clinical outcomes such as development of hepatocellular carcinoma (HCC). We estimated that there are 1.5 million CHB-infected persons in Shanghai. The M&T strategy costs US$20,730 per patient and yields a discounted QALY of 15.45, which represents incremental costs and health benefits of US$275 and 0.10 QALYs compared to current practice, and an ICER of US$2,996 per QALY gained. In the base case, we estimated that the M&T strategy will reduce HCC and CHB-related mortality by only around 1%. If variables such as adherence to monitoring and treatment could be substantially improved the M&T strategy could reduce HCC by 70% and CHB-related mortality by 83%.

CONCLUSION

Lifelong monitoring of inactive CHB carriers is cost-effective in Shanghai according to typical benchmarks for value for money, but achieving substantial population-level health gains depends on identifying more CHB-infected cases in the population, and increasing rates of treatment, monitoring, and treatment adherence.

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.

Is increasing the dose of Entecavir effective in partial virological responders?

OBJECTIVE

To analyze the effect of increasing Entecavir (ETV) dosage in patients with chronic hepatitis B (CHB) who partially responded to ETV after 1 year.

METHODS

Twenty-three hepatitis B e antigen (HBeAg)-positive and 36 HBeAg-negative patients with CHB were treated with ETV 0.5 mg daily. After 1 year of the treatment, those with detectable hepatitis B virus (HBV-DNA) were randomized to either ETV 0.5 mg or 1 mg daily. The resistance to ETV was excluded. Both groups received ETV for 3 years. The groups were compared in aspects of undetectable DNA.

RESULTS

Group 1 was given 0.5 mg ETV and included 32 patients (20 HBeAg-negative and 12 HBeAg-positive). Group 2 was given 1 mg ETV and consisted of 27 patients (16 HBeAg-negative and eleven HBeAg-positive). Group 2 had more effective suppression of HBV-DNA while both groups had comparable rates of HBeAg loss (58% and 63% for group 1 and group 2, respectively) and alanine transaminase (ALT) normalization at the end of 4 years.

CONCLUSION

Increasing ETV dose from 0.5 mg to 1 mg after 1 year of ETV treatment may provide an effective suppression of viral replication.

New therapeutic perspectives in HBV: when to stop NAs

The goal of chronic hepatitis B (CHB) treatment is to achieve seroclearance of HBsAg. Nucleos(t)ide analogues (NAs) are one of the first-line treatments for CHB. NAs produce a potent suppression of viral replication but are associated with a low rate of HBsAg seroclearance and a high risk of virological relapse after discontinuation. Because of these reasons, long-term treatment is needed. They are well-tolerated oral drugs, and it seems they do not produce important side-effects in long-term administration. The duration of NA treatment remains unclear, nevertheless, in some patients NAs can be stopped with a low rate of relapse. HBeAg-positive patients could discontinue NA therapy if they achieved HBeAg seroclearance and maintain undetectable HBV DNA. For HBeAg-negative patients, to stop NA treatment is not recommended. In addition to other factors, serum HBsAg titres during treatment have recently been proposed to guide NA-based therapy duration in selected patients. All patients could be stopped from taking treatment if they achieve HBsAg loss.

Then and now: The progress in hepatitis B treatment over the past 20 years

The ultimate goals of treating chronic hepatitis B (CHB) is prevention of hepatocellular carcinoma (HCC) and hepatic decompensation. Since the advent of effective antiviral drugs that appeared during the past two decades, considerable advances have been made not only in controlling hepatitis B virus (HBV) infection, but also in preventing and reducing the incidence of liver cirrhosis and HCC. Furthermore, several recent studies have suggested the possibility of reducing the incidence of recurrent or new HCC in patients even after they have developed HCC. Currently, six medications are available for HBV treatment including, interferon and five nucleoside/nucleotide analogues. In this review, we will examine the antiviral drugs and the progresses that have been made with antiviral treatments in the field of CHB.

Prior exposure to lamivudine increases entecavir resistance risk in chronic hepatitis B Patients without detectable lamivudine resistance

The efficacy of entecavir (ETV) treatment in chronic hepatitis B (CHB) patients who were exposed to lamivudine (LAM) but had no detectable LAM resistance (LAM-R) is not well evaluated. In this study, we aimed to evaluate whether the probability of developing genotypic resistance to ETV in LAM-exposed patients with or without LAM-R is comparable to that in antiviral-naive patients. This retrospective cohort study included 500 consecutive patients with CHB who started ETV monotherapy at a single tertiary hospital in Korea. The patients were divided into three groups: nucleos(t)ide analogue (NA)-naive patients (group 1, n=142), patients who were previously exposed to LAM and had no currently or previously detected LAM-R (group 2, n=233), and patients with LAM-R when starting ETV (group 3, n=125). The overall median ETV treatment duration was 48.7 months. The probabilities of virologic breakthrough were significantly increased not only in group 3 (hazard ratio [HR]=14.4, P<0.001) but also in group 2 (HR=5.0, P<0.001) compared to group 1. Genotypic ETV resistance (ETV-R) developed more frequently in group 2 (HR=13.0, P=0.013) as well as group 3 (HR=43.9, P<0.001) than in group 1: the probabilities of developing ETV-R in groups 1, 2, and 3 were <1.0%, 8.0%, and 28.2%, respectively, at month 48. The results of this study indicate that ETV-R occurred more frequently in LAM-exposed patients, even though they had no detectable LAM-R, than in NA-naive patients. Therefore, LAM-exposed CHB patients, regardless of the presence or absence of LAM-R, should be monitored more cautiously for the development of ETV-R during ETV monotherapy.

Is increasing the dose of Entecavir effective in partial virological responders?

OBJECTIVE

To analyze the effect of increasing Entecavir (ETV) dosage in patients with chronic hepatitis B (CHB) who partially responded to ETV after 1 year.

METHODS

Twenty-three hepatitis B e antigen (HBeAg)-positive and 36 HBeAg-negative patients with CHB were treated with ETV 0.5 mg daily. After 1 year of the treatment, those with detectable hepatitis B virus (HBV-DNA) were randomized to either ETV 0.5 mg or 1 mg daily. The resistance to ETV was excluded. Both groups received ETV for 3 years. The groups were compared in aspects of undetectable DNA.

RESULTS

Group 1 was given 0.5 mg ETV and included 32 patients (20 HBeAg-negative and 12 HBeAg-positive). Group 2 was given 1 mg ETV and consisted of 27 patients (16 HBeAg-negative and eleven HBeAg-positive). Group 2 had more effective suppression of HBV-DNA while both groups had comparable rates of HBeAg loss (58% and 63% for group 1 and group 2, respectively) and alanine transaminase (ALT) normalization at the end of 4 years.

CONCLUSION

Increasing ETV dose from 0.5 mg to 1 mg after 1 year of ETV treatment may provide an effective suppression of viral replication.

Add-on peg-interferon leads to loss of HBsAg in patients with HBeAg-negative chronic hepatitis and HBV DNA fully suppressed by long-term nucleotide analogs

BACKGROUND AND OBJECTIVE

The aim of this study was to prospectively evaluate whether the addition of peg-IFN to a stable NA regimen leads to loss of HBsAg in HBeAg-negative patients with chronic hepatitis and HBV DNA fully suppressed by long-term NA treatment.

STUDY DESIGN

We analyzed HBsAg levels in 10 HBsAg-positive, HBeAg-negative patients who received peg-IFN alpha-2a in addition to a NA regimen. Treatment lasted a maximum of 96 weeks, according to changes in the HBsAg titer. Before peg-IFN therapy, HBV DNA levels had been below the limit of detection for at least three years.

RESULTS

HBsAg levels declined in nine patients. Among these nine, four became HBsAg-negative after 48 weeks of peg-IFN treatment; these patients received peg-IFN for only 48 weeks. NAs were stopped in these four patients, and these levels remained stable for at least 18 months (loss of HBsAg; HBV-DNA negative). HBs seroconversion was observed in two patients. The remaining five patients received 96 weeks of peg-IFN therapy. One patient became HBsAg-negative at the end of peg-IFN therapy; another became HBsAg-negative six months later. Three patients did not become HBsAg-negative. NAs were stopped in the two patients who became HBsAg-negative with no relapse during 12 months of follow up.

CONCLUSIONS

In HBsAg-positive, HBeAg-negative patients with HBV DNA were fully suppressed by long-term NA treatment, the addition of peg-INF for a maximum of 96 weeks based on HBsAg-titer monitoring led to a loss of HBsAg and cessation of NA therapy in six out of ten patients, with no relapse for 12-18 months of follow up. HBs seroconversion was observed in two patients.

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.

A Novel Estimation of the Impact of Treatment with Entecavir on Long-Term Mortality, Morbidity, and Health Care Costs of Chronic Hepatitis B in China

OBJECTIVES

Health care decision makers are increasingly concerned about the value of chronic hepatitis B (CHB) treatments in China. This analysis aims at estimating the relative value of entecavir as a first-line option at treatment initiation and for different treatment durations from a holistic perspective.

METHODS

CHB was simulated by using a Markov disease transition model with disease states based on available natural history data. The model assumed 5-year treatment duration with entecavir, lamivudine, telbivudine, and adefovir based on published clinical data. The speed of disease progression varies by viral load and hepatitis B "e" antigen status. Direct medical costs included medication and management of liver complications. The primary output was the estimated cost savings of entecavir per patient per day versus the comparator.

RESULTS

For treatment duration of 5 years and a follow-up period of 30 years, entecavir treatment was translated into specific patient benefit of an estimated cost saving of $2.69 per day compared with no treatment. In addition, long-term usage of entecavir resulted in daily $2.33 and $1.73 cost saving compared with short-term usage (1-year and 2-year, respectively). Among available treatment options in China, entecavir treatment exhibited about $0.90 to $1.81 daily cost saving versus the comparators. The detailed daily cost saving of entecavir is summarized as follows-entecavir versus lamivudine: $1.81, entecavir versus telbivudine: $0.90, entecavir versus adefovir: $2.02, and entecavir versus generic adefovir: $1.37.

CONCLUSIONS

Long-term usage of entecavir exhibits the characteristics of a favorable CHB treatment, which translates into economic value as opposed to either no treatment or alternative strategies.

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.

Australian tertiary care outcomes of entecavir monotherapy in treatment naive patients with chronic hepatitis B

AIM: To evaluate the long-term treatment outcomes of entecavir monotherapy in treatment naive patients in an Australian tertiary care setting.

METHODS: A retrospective analysis of treatment naive patients receiving entecavir monotherapy through Westmead Hospital was performed. Patients were excluded if they had received previous treatment with another nucleoside or nucleotide analogue, were pregnant or less than 18 years old.

RESULTS: Out of 336 patients, 163 patients fulfilled the selection criteria. Range of follow up was 3-46 mo (mean 26 mo). 134 patients (82.2%) had pre-treatment biopsies, with 26 patients (16.0 %) demonstrating F3-4 fibrosis. In total, 153 patients (93.9%) achieved at least Partial Virological Suppression (PVS), with 134 patients (82.2%) achieving complete virological suppression. The cumulative CVS and PVS rates at 36 mo were 92.2% and 97.3%, respectively. 3 patients (1.8%) failed to achieve PVS, while 5 patients (3.0%) developed virological rebound. 128 patients (78.5%) maintained CVS throughout follow up. Predictors of CVS included lower baseline DNA level (P = 0.001), hepatitis B virus e antigen negative status (P = 0.001) and increasing age at treatment (log rank 0.001). No significant adverse effects were reported necessitating cessation of entecavir.

CONCLUSION: Entecavir monotherapy is efficacious and safe in an Australian tertiary care setting. Resistance and rebound rates are very low. This is similar to data from controlled and uncontrolled trials around the world.

Cost effectiveness of first-line oral antiviral therapies for chronic hepatitis B : a systematic review

BACKGROUND

Chronic hepatitis B is a common, progressive disease, particularly when viral replication is detected. Oral antivirals can suppress viral replication and prevent or delay the development of cirrhosis and liver-related complications.

OBJECTIVE

The aim of this study was to systematically review the quality of cost-effectiveness evidence on first-line treatment with entecavir (ETV) or tenofovir difumarate (TDF) for patients with chronic hepatitis B.

METHODS

We searched electronic databases and retrieved articles published up to October 2011, in which the cost effectiveness of ETV or TDF was compared with that of other oral antivirals. The quality of the studies identified was assessed with a standard checklist for critical appraisal.

RESULTS

We selected 16 original papers, all published in the last 5 years. There was a conflict of interest in 12 of the 16 studies due to sponsorship by the corresponding pharmaceutical companies. According to the validity assessment, ten studies were classified as high quality. Five studies performed a cost-effectiveness analysis comparing ETV with TDF; they concluded that TDF dominates ETV. The other 11 studies compared ETV or TDF with other strategies; all concluded that ETV and TDF are both cost-effective interventions.

CONCLUSIONS

This systematic review shows that there is valid evidence suggesting that ETV and TDF are cost-effective interventions for the treatment of patients with chronic hepatitis B in many health systems. In countries where both alternatives are available, it appears that TDF dominates ETV. These results could help decision makers and clinicians to understand economic issues regarding the available drugs for first-line treatment of hepatitis B.

Considerations for the long-term treatment of chronic hepatitis B with nucleos(t)ide analogs

Treatment of chronic hepatitis B (CHB) with nucleos(t)ide analogs is often required over a prolonged period to achieve durable virologic suppression. One barrier to the success of long-term therapy is the emergence of drug-resistant mutants. Current guidelines therefore recommend the most potent drugs with optimal resistance profiles, that is, entecavir and tenofovir are used as first-line monotherapies in CHB. Characteristics of the hepatitis B virus, the disease, the patient and the drug can influence the response to antiviral treatment and risk of relapse. This review discusses factors to consider maximizing the chances of successful long-term treatment of CHB, and provides an overview of the long-term efficacy and safety data that have become available over the 4-5 years since entecavir and tenofovir were first approved for the treatment of CHB. Recent findings on whether and under what circumstances long-term therapy of CHB might be stopped are also discussed.

Direct acting antivirals for the treatment of chronic viral hepatitis

The development and evaluation of antiviral agents through carefully designed clinical trials over the last 25 years have heralded a new dawn in the treatment of patients chronically infected with the hepatitis B and C viruses, but not so for the D virus (HBV, HCV, and HDV). The introduction of direct acting antivirals (DDAs) for the treatment of HBV carriers has permitted the long-term use of these compounds for the continuous suppression of viral replication, whilst in the case of HCV in combination with the standard of care [SOC, pegylated interferon (PegIFN), and ribavirin] sustained virological responses (SVRs) have been achieved with increasing frequency. Progress in the case of HDV has been slow and lacking in significant breakthroughs.This paper aims to summarise the current state of play in treatment approaches for chonic viral hepatitis patients and future perspectives.

The cost-effectiveness of treating chronic hepatitis B patients in a median endemic and middle income country

BACKGROUND/AIMS

Chronic hepatitis B (CHB) infection is a serious public health problem due to its potential liver disease sequelae and highly expensive medical costs such as the need for liver transplantation. The aim of this study was to quantify the burden of active CHB in terms of mortality and morbidity, the eligibility of antiviral treatment and to assess various treatment scenarios and possible salvage combinations for cost-effectiveness.

METHODS

A population cohort from a large data base of chronic hepatitis B patients was constructed and stratified according to 10-year age groups, the prevalence of HBsAg, HBV DNA level, ALT level, HBeAg status and the presence of cirrhosis. An age-specific Markov model for disease progression and cost-effectiveness analysis was constructed and calibrated for the specific population setting.

RESULTS

Of about 3.2 million estimated HBsAg carriers, 25% are eligible for treatment. If the active cohort remains untreated, 31% will die due to liver related complications. Within a 20-year period, 11% will have developed decompensated cirrhosis, 12% liver cancer and 6% will need liver transplantation. Quality adjusted life years (QALYs) for the no treatment scenario ranged from 9.3 to 14.0. For scenarios with antiviral treatment, QALYs ranged from 9.9 to 14.5 for lamivudine, 13.0-17.5 for salvage therapy, and 16.6-19.0 for the third generation drugs entecavir and tenofovir.

CONCLUSION

In a country with considerable amount of active CHB patients, monotherapy with a highly potent third generation drug has the most health-gain, and is cost-effective in both HBeAg-positive and negative in all stages of liver disease.

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.

Long-term follow-up of hepatitis B e antigen-negative patients treated with peginterferon α-2a: progressive decrease in hepatitis B surface antigen in responders

OBJECTIVE

Peginterferon (PEG-IFN) is considered as a first-line treatment option for hepatitis B e antigen (HBeAg)-negative chronic hepatitis B. We aimed to evaluate the long-term response to PEG-IFN in HBeAg-negative patients.

METHODS

All patients enrolled in the PARC study who completed the treatment phase were eligible for this long-term follow-up (LTFU) study. Patients received PEG-IFN α-2a (180 μg weekly) ± ribavirin (1000-1200 mg daily) for 48 weeks and had at least one additional LTFU visit after the initial follow-up period of 24 weeks (mean duration 2.1 ± 0.2 years). Retreated patients were considered nonresponders.

RESULTS

Of 117 patients who completed the treatment phase, 79 (68%) were included in this LTFU study. Among 19 patients with a combined response at 24 weeks after treatment [initial responders; hepatitis B virus DNA<10 000 copies/ml (<1714 IU/ml) and normal alanine aminotransferase], 12 (63%) sustained this response through LTFU. Three additional patients showed such a response at LTFU, resulting in a total of 15 (19%) combined responders at LTFU. A marked decrease in the serum hepatitis B surface antigen (HBsAg) levels was observed in initial responders, resulting in HBsAg clearance in 26% of the patients (6% of all LTFU participants).

CONCLUSION

About one-third of HBeAg-negative patients with a response to PEG-IFN at 24 weeks after treatment subsequently had a relapse during 2 years of follow-up. Despite the limited overall efficacy of PEG-IFN, patients responding to PEG-IFN treatment showed a marked decrease in serum HBsAg, resulting in a high rate of HBsAg clearance, which indicates the need for predictors of response to PEG-IFN in HBeAg-negative disease.

Targeted DNA mutagenesis for the cure of chronic viral infections

Human immunodeficiency virus type 1 (HIV-1), hepatitis B virus (HBV), and herpes simplex virus (HSV) have been incurable to date because effective antiviral therapies target only replicating viruses and do not eradicate latently integrated or nonreplicating episomal viral genomes. Endonucleases that can target and cleave critical regions within latent viral genomes are currently in development. These enzymes are being engineered with high specificity such that off-target binding of cellular DNA will be absent or minimal. Imprecise nonhomologous-end-joining (NHEJ) DNA repair following repeated cleavage at the same critical site may permanently disrupt translation of essential viral proteins. We discuss the benefits and drawbacks of three types of DNA cleavage enzymes (zinc finger endonucleases, transcription activator-like [TAL] effector nucleases [TALENs], and homing endonucleases [also called meganucleases]), the development of delivery vectors for these enzymes, and potential obstacles for successful treatment of chronic viral infections. We then review issues regarding persistence of HIV-1, HBV, and HSV that are relevant to eradication with genome-altering approaches.

Chronic hepatitis B infection

The management of chronic hepatitis B virus (HBV) infection requires understanding the natural history of the disease as well as the risks, benefits, and limitations of the therapeutic options. This article covers the principles governing when to start antiviral therapy, discusses recent advances using hepatitis B surface antigen quantification to better define various phases of infection, describes the use of HBV core, precore, and viral genotyping as well as host IL28B genotyping to predict response to interferon therapy, and reports on the management of HBV in 3 special populations (pregnancy, postliver transplantation, and in the setting of chemotherapy or immunosuppression).