Randomized, placebo-controlled trial of tenofovir disoproxil fumarate in adolescents with chronic hepatitis B

From tenofovir disoproxil fumarate (TDF) to tenofovir alafenamide (TAF): perspectives in pediatric patients

INTRODUCTION

Hepatitis B virus (HBV) affects hundreds of millions globally, with many cases stemming from perinatal transmission. Chronic hepatitis B (CHB) in children can progress to cirrhosis and hepatocellular carcinoma (HCC) in adulthood. Treatment options include interferons and nucleos(t)ide reverse transcriptase inhibitors (N[t]RTIs) such as tenofovir alafenamide (TAF).

AREAS COVERED

This review covers the epidemiology of pediatric CHB and current treatments, with a focus on tenofovir-based therapies, particularly tenofovir disoproxil fumarate (TDF) and TAF. TDF has been used for years, but its risks of bone mineral density loss and renal impairment have raised concerns. TAF, with lower systemic exposure, appears to mitigate these risks. Ongoing trials are evaluating TAF's safety in younger children. There are knowledge gaps in long-term safety and the potential for combination therapies.

EXPERT OPINION

TAF offers a safer alternative to TDF for children with CHB, showing high antiviral efficacy and fewer side effects. However, more data is needed on its use in younger children and long-term safety. The future of CHB treatment in pediatrics may include combination therapies and personalized approaches, potentially improving outcomes and minimizing risks over a lifetime of treatment. As research progresses, TAF is likely to become a cornerstone in pediatric CHB management.

Determinants of HBeAg loss during follow-up of a multiethnic pediatric cohort

Hepatitis B e antigen (HBeAg) loss is a key event in the natural history of chronic hepatitis B virus infection. The rate and determinants of HBeAg loss depend upon cohort characteristics at baseline. Few studies have examined the age-dependent rate, and none have examined the effect of patient sex and ethnicity on the age-dependant rate. The study of age-dependent rates requires the identification and long-term follow-up of a pediatric cohort. We have studied the age-dependent rate of HBeAg loss, and the rate of HBeAg loss measured from baseline, in a multi-ethnic cohort of 454 pediatric patients. During observation, HBeAg loss was observed in 121/303 (39.9%) HBeAg-positive patients. The rate of HBeAg loss was greater in the second versus the first and third decades of life. The age-related rate of HBeAg loss was clearly affected by patient sex and ethnicity, with earlier loss observed for males and for White versus both South Asian and Chinese ethnicities. When measured from baseline, Chinese patients had a slower rate of HBeAg loss in comparison with White patients. In multivariate analysis of HBeAg loss during prolonged follow-up, male sex, older age, and White ethnicity were associated with HBeAg loss, but antiviral treatment was not.

The Efficacy of Antiviral Treatment for Chronic Hepatitis B Patients with Normal ALT Levels: A Systematic Review and Meta-analysis

Context: When nucleos(t)ide analogues (NAs) were applied clinically to manage chronic hepatitis B virus infection, the prognosis of chronic hepatitis B (CHB) patients greatly improved. However, certain CHB patients with normal alanine aminotransferase (ALT) levels were not used to be considered as the population with the need for antiviral treatment. Objectives: This systematic review and meta-analysis collected and analyzed data from clinical trials to assess and compare the efficacy of antiviral treatment among patients with elevated and normal ALT levels. Methods: A systematic search was performed to gather studies published from 1990.01 to 2022.08 in PubMed and Web of Science databases. The quality of the literature was assessed, and 16 studies were included for further analysis. Basic information on included studies and study populations was collected. A meta-analysis was carried out to evaluate three major outcomes of viral response, hepatitis B envelope antigen (HBeAg) loss, and HBeAg seroconversion after NAs treatment based on data extracted from these studies. Odds ratios (ORs) with 95% confidence intervals (CIs) for all outcomes were calculated using fixed-effects models. Results: In the 16 relevant studies, 5,345 patients met the inclusion criteria, including 3,687 patients receiving NAs treatment. All patients were grouped into one with elevated ALT and another with normal ALT based on whether their pretreatment ALT levels > 1*upper limit of normal (ULN). For patients receiving lamivudine, the viral response showed no significant difference between the groups with elevated and normal ALT levels (pooled log OR: 0.51 [-0.23 - 1.26], P = 0.79); the pooled log OR for HBeAg loss was 1.19 (0.63 - 1.76, P = 0.03) and pooled log OR for HBeAg seroconversion was 2.19 (0.91 - 3.47, P = 0.40). For patients receiving first-line therapy with tenofovir disoproxil fumarate (TDF) and entecavir (ETV), the viral response showed no significant difference between the two groups: Pooled log OR (0.38 [-0.22 - 0.97], P = 0.10). The pooled log OR for HBeAg loss and HBeAg seroconversion was (-0.07 [-0.81 - 0.67], P = 0.68) and (0.40 [-0.84 - 1.63], P = 0.88), respectively. Conclusions: The efficacies of first-line therapy with TDF and ETV treatments were similar in groups with elevated and normal ALT levels for the outcomes of viral response and HBeAg loss. These findings may support further treatment of CHB patients with normal ALT levels.

Incidence and Predictors of Relapse After Stopping Antiviral Therapy in Pediatric Chronic Hepatitis B

BACKGROUND

There are no definite end-points for stopping therapy in pediatric chronic hepatitis B (CHB). The study objective was to evaluate the incidence of relapse after stopping antiviral therapy and to identify its predictors.

METHODS

All hepatitis B surface antigen (HBsAg) positive children presenting to our hospital, who had been on antivirals for at least 2 years with undetectable hepatitis B virus-deoxyribonucleic acid (HBV-DNA) and normal alanine aminotransferase (ALT) on 3 consecutive occasions over last 12 months were included. Antivirals were stopped if liver biopsy showed histological activity index <5 and fibrosis (Ishak) <3. Virological relapse was defined as the elevation of HBV-DNA (>2000 IU/mL) and biochemical relapse as a rise in ALT levels to >2 times the upper limit of normal. Those having biochemical relapse were started on pegylated interferon alpha-2b-based sequential therapy.

RESULTS

Of the 114 children with CHB screened, 31 HBsAg-positive children fulfilled inclusion criteria and antivirals were stopped in them. Virological and biochemical relapse was seen in 12 (38.7%) and 5 (16.1%) children within 12 months of stopping antiviral treatment. On Cox regression, hepatitis B e antigen (HBeAg) positive status at the time of stopping antiviral therapy (HR: 6.208, 95% CI: 1.630-23.638) and longer time taken for HBV-DNA to become undetectable while on antivirals (HR: 1.027, 95% CI: 1.000-1.055) were the independent predictors of relapse.

CONCLUSION

Discontinuation of antiviral treatment in children with CHB resulted in relapse in one-third of the patients. Relapse was frequent in those who were HBeAg-positive at the time of stopping therapy and in those who required longer therapy for HBV-DNA to become undetectable.

Treatment of hepatitis B virus infection in children and adolescents

Hepatitis B virus (HBV) infection is one of the main causes of morbidity and mortality worldwide. Most children acquire the infection perinatally or during early childhood and develop a chronic hepatitis characterized by a high viral replication and a low-inflammation phase of infection, with normal or only slightly raised aminotransferases. Although a conservative approach in children is usually recommended, different therapies exist and different therapeutic approaches are possible. The main goals of antiviral treatment for children with chronic HBV infection are to suppress viral replication and to warn the disease progression to cirrhosis and hepatocellular carcinoma, although these complications are rare in children. Both United States Food and Drug Administration (US-FDA) and European Medicines Agency (EMA) have approved interferon alfa-2b for children aged 1 year and older, pegylated interferon alfa-2a and lamivudine for children aged 3 years and older, entecavir for use in children aged 2 years and older, and adefovir for use in those 12 years of age and older. Tenofovir disoproxil fumarate is approved by EMA for children aged 2 years and older and by US-FDA for treatment in children aged 12 years and older. Finally, EMA has approved the use of tenofovir alafenamide for treatment of children aged 12 years and older or for children weighing more than 35 kg independent of age. This narrative review will provide the framework for summarizing indications to antiviral therapy in the management of chronic HBV infection in children and adolescents.

Hepatitis B virus genome diversity in adolescents: Tenofovir disoproxil fumarate treatment effect and HBeAg serocon version

More systematic analysis of hepatitis B virus (HBV) genome diversity, linked with tenofovir disoproxil fumarate (TDF) treatment and HBeAg seroconversion, are needed. GS-US-174-0115 was a double-blind, placebo-controlled, Phase 3, 192-week clinical trial that evaluated TDF in adolescents with chronic hepatitis B (CHB). HBV full-genome deep sequencing was performed using Illumina MiSeq at baseline (BL; n = 85), Week 8 (W8; n = 80), Week 72 (W72; PBO only, n = 42), and treatment-free follow-up (TDF only, n = 25). The viral diversity was calculated using Shannon entropy and population nucleotide diversity with a 2% variant cutoff. Our data showed (i) a higher viral diversity in the X region at baseline than the core/polymerase/surface regions, (ii) higher core/surface viral diversity at baseline for patients with seroconversion, (iii) an expected reduction in viral diversity after 8 weeks of TDF treatment, and (iv) a drop in viral diversity at W72 for patients receiving placebo with a seroconversion (n = 7). The higher viral diversity in X was associated with higher baseline alanine aminotransferase (ALT) levels (p < .001). Patients with greater reduction of diversity at W8 of TDF treatment had higher baseline ALT levels. For placebo patients who seroconverted, the drop in viral diversity at W72 (p = .04) coincided with reduction of serum HBV DNA (average change from baseline = -4.10 log10 copies/ml) and unique combinations of variants were enriched in a patient's viral population post seroconversion. The basal core promoter (BCP) variants, A1762T and G1764A, and the pC variant, G1896A, were most often enriched at or after seroconversion.

Breakthroughs and challenges in the management of pediatric viral hepatitis

Chronic infections by hepatitis B virus (HBV) and hepatitis C virus (HCV) major causes of advanced liver disease and mortality worldwide. Although regarded as benign infections in children, their persistence through adulthood is undoubtedly of concern. Recent advances in HCV treatment have restored the visibility of these conditions and raised expectations for HBV treatment, which is currently far from being curative. Herein we describe direct-acting antivirals available for pediatric HCV (sofosbuvir/ledipasvir, sofosbuvir/velpatasvir, glecaprevir/pibrentasvir) and their real-world use. A critical review of the HBV pediatric classification is provided. Anti-HBV investigational compounds are reviewed in light of the pathophysiology in the pediatric population, including capsid assembly modulators, antigen secretion inhibitors, silencing RNAs, and immune modifiers. Recommendations for screening and management of immunosuppressed children or those with other risk factors or comorbidities are also summarized.

Management of Hepatitis-B Virus Infection in Immunocompromised Children: A Single Center Experience

OBJECTIVES

The aims of the study was to expand the pediatric experience on hepatitis-B virus (HBV) reactivation, a known complication in patients with hematologic malignancies or on immunosuppression.

METHODS

Retrospective appraisal of HBV therapy/prophylaxis in immunocompromised children, studied from April 2006 to March 2020.

RESULTS

Eighteen HBV-positive patients, 5 girls, median age 11.1 (4.1--17.9) years were included. Seventeen of 18 were immunosuppressed at HBV-infection diagnosis. Seventeen were at high risk of reactivation, 1 at moderate risk. Five of 18 had acute hepatitis B as first infection or reactivation, 6 had HBeAg-positive infection, 1 an HBeAg-negative infection and 6 HBsAg-negative infection. Median follow-up was 2.7 (0.7--12.5) years. No HBV-related mortality was observed. Prophylaxis had to be repeated in 1. Lamivudine was used in 6/12 viremic patients and HBV-DNA negativization obtained in 2/6 (33%). Tenofovir-DF was used in 2/12 and entecavir in 4/12: 100% attained HBV-DNA negativization. Therapy had to be switched from tenofovir-DF to entecavir in 1 patient because of renal impairment. Virological breakthroughs were observed in 1 lamivudine-treated patient, leading to a hepatitis flare; 1 patient on entecavir had a hepatitis flare at immunoreconstitution. Mortality was 33% in the HBsAg-positive group. Seven prophylactic treatments were administered to 6 patients with HBsAg-negative infection: tenofovir-DF in 2 HBV-DNA-positive, lamivudine in 5 HBV-DNA-negative, without reverse HBsAg seroconversion, morbidity or mortality.

CONCLUSIONS

There is a residual risk of acute hepatitis B in immunocompromised children, mortality rate was substantial, potentially related to the delays in commencing chemotherapy caused by liver dysfunction. Tenofovir-DF or entecavir are the drugs of choice for HBV treatment in immunocompromised children.

Pharmacotherapy options for managing hepatitis B in children

INTRODUCTION

To eliminate viral hepatitis by 2030, the World Health Organization (WHO) launched the first global health sector strategy on viral hepatitis, with particular focus given to hepatitis B and C in 2016. To achieve the reduction of mortality in children, it is indispensable to know which children should be treated and how to treat them.

AREA COVERED

In this article, the authors review the antiviral treatment of children with chronic hepatitis B virus (HBV) infection including antivirals available for children with chronic HBV infection.

EXPERT OPINION

The approvals of nucleos(t)ide analogues (NAs) and pegylated interferon (PEG-IFN) for children have lowered a hurdle to the initiation of antiviral treatment in children. The international guidelines use nearly the same criteria of antiviral treatment for children with chronic HBV infection, but the WHO guidelines provide a cautious stance on the antiviral treatment of children. Not only PEG-IFN but also NAs with a high genetic barrier to drug resistance should be the first-line treatment for children. In settings with limited medical resources, NAs can be the first-line treatment for children. Although the concept of an 'immune-tolerant phase' is challenged, evidence is not sufficient to recommend the treatment of HBeAg-positive immune-tolerant children.

Screening for Hepatitis B Virus Infection in Nonpregnant Adolescents and Adults: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force

Importance

A 2014 review for the US Preventive Services Task Force (USPSTF) found antiviral therapy for hepatitis B virus (HBV) infection associated with improved intermediate outcomes, although evidence on clinical outcomes was limited.

Objective

To update the 2014 HBV screening review in nonpregnant adolescents and adults to inform the USPSTF.

Data Sources

Cochrane Central Register of Controlled Trials, the Cochrane Database of Systematic Reviews, and Ovid MEDLINE (2014 to August 2019); with surveillance through July 24, 2020.

Study Selection

Randomized clinical trials (RCTs) on screening and antiviral therapy; cohort studies on screening, antiviral therapy clinical outcomes, and the association between achieving intermediate outcomes after antiviral therapy and clinical outcomes.

Data Extraction and Synthesis

One investigator abstracted data; a second investigator checked accuracy. Two investigators independently assessed study quality. Random-effects profile likelihood meta-analysis was performed.

Results

Thirty trials and 20 cohort studies, with a total of 94 168 participants, were included. No study directly evaluated the effects of screening for HBV infection vs no screening on clinical outcomes such as mortality, hepatocellular carcinoma, or cirrhosis. Screening strategies that focused on risk factors such as ever having immigrated from high-prevalence countries and demographic and behavioral risk factors would identify nearly all HBV infection cases. In 1 study (n = 21 008), only screening immigrants from high-prevalence countries would miss approximately two-thirds of infected persons. Based on 18 trials (n = 2972), antiviral therapy compared with placebo or no treatment was associated with greater likelihood of achieving intermediate outcomes, such as virologic suppression and hepatitis B e-antigen (HBeAg) or hepatitis B surface antigen loss or seroconversion; the numbers needed to treat ranged from 2.6 for virologic suppression to 17 for HBeAg seroconversion. Based on 12 trials (n = 4127), first-line antiviral therapies were at least as likely as nonpreferred therapies to achieve intermediate outcomes. Based on 16 trials (n = 4809), antiviral therapy might be associated with improved clinical outcomes, but data were sparse and imprecise. Nine cohort studies (n = 3893) indicated an association between achieving an intermediate outcome following antiviral therapy and improved clinical outcomes but were heterogeneous (hazard ratios ranged from 0.07 to 0.87). Antiviral therapy was associated with higher risk of withdrawal due to adverse events vs placebo or no antiviral therapy.

Conclusions and Relevance

There was no direct evidence for the clinical benefits and harms of HBV screening vs no screening. Antiviral therapy for HBV infection was associated with improved intermediate outcomes and may improve clinical outcomes.

Present and future management of viral hepatitis B and C in children

Having a hepatitis B virus (HBV) or hepatitis C virus (HCV) infection places a child at higher risk for subsequent chronic hepatitis B (CHB) or chronic hepatitis C (CHC) infection. The risk of mother-to-child transmission is higher for HBV (20% to 90%) than for HCV (<5%). Perinatal HBV infection generally causes CHB infection while perinatal HCV infection has a certain rate of spontaneous viral clearance (around 20% to 30%). Of the two, only HBV infection can benefit from passive/active perinatal immunoprophylaxis. The risk of CHB in children with HBV horizontal transmission decreases with age, whereas HCV transmission among teenagers commonly results into a long-life infection and CHC infection. Children with CHB or CHC should be carefully assessed for the need for antiviral treatment. When treatment cannot be deferred, pediatric CHB infection has different first-line treatment options: standard interferon (for children aged≥1 year), pegylated interferon (for children aged≥3 years), and the oral nucleotide analogues entecavir (for children aged≥2 years) and tenofovir (for children aged≥12 years). The choice of treatment depends on the child's age, virus genotypes, previous treatment failure and presence of contraindications. Expected responsiveness rate is 25% of hepatitis B e-antigen clearance, with both standard interferon and nucleotide analogues. Direct antiviral agents are first-line treatment for CHC infection in children aged 3 years or older. Hepatitis C virus sustained virus response is as high as 97%. Therefore, if direct antiviral agents can be proven to be safe and well tolerated in very young children, HCV eradication could be planned after the first screening.

Management of Hepatitis B Virus Infection and Prevention of Hepatitis B Virus Reactivation in Children With Acquired Immunodeficiencies or Undergoing Immune Suppressive, Cytotoxic, or Biological Modifier Therapies

Reactivation of hepatitis B virus (HBV) is a known complication of immune-suppressive, cytotoxic, and biological modifier therapies in patients currently infected with HBV or who have had past exposure to HBV. Nowadays, newer and emerging forms of targeted biologic therapies are available for the management of rheumatologic conditions, malignancies, inflammatory bowel disease, dermatologic conditions and solid-organ, bone marrow, or haematologic stem cell transplant but there is currently a lack of a systematic approach to the care of patients with or at risk of HBV reactivation. The Hepatology Committee of the European Society of Pediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) together with a working group of ESPGHAN members with clinical and research expertise in viral hepatitis developed an evidence-based position paper on reactivation of HBV infection in children identifying pertinent issues addressing the diagnosis, prevention, and treatment of this condition. Relevant clinical questions were formulated and agreed upon by all the members of the working group. Questions were answered and positions were based on evidence resulting from a systematic literature search on PubMed and Embase from their inception to July 1, 2019. A document was produced and the working group and ESPGHAN Hepatology Committee members voted on each recommendation, using a formal voting technique. A recommendation was accepted provided upon agreement by at least 75% of the working group members. This position paper provides a comprehensive update on the diagnosis, prevention and treatment of HBV reactivation in children.

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.

Entecavir is Safe and Effective in Long Term for the Treatment of Hepatitis B in Immunocompromised Children

OBJECTIVE

Hepatitis B infection is common in patients with cancer, and prompt treatment is necessary; otherwise, it can result in life-threatening complications. The objective of this study was to assess the long-term safety and efficacy of entecavir in immunocompromised children with hepatitis B.

METHODS

This single-center prospective study was conducted on children with different malignancies referred to our department with evidence of hepatitis B infection. Only those children were included in the study who had HBsAg positive and alanine aminotransferase (ALT) more than 2 times the upper limit of normal and whose hepatitis B virus (HBV) DNA was more than 20,000IU/ml. These children were put on entecavir and prospectively observed upto 192 weeks. Primary efficacy end point was the proportion of patients who achieved undetectable HBV DNA at 48 weeks of treatment. Other efficacy end points were the proportion of patients with HBeAg seroconversion, undetectable HBV DNA, and ALT normalization at weeks 48 and 96 weeks.

RESULTS

A total of 41 children met the inclusion criteria, of which 5 children died because of malignancy and 5 were lost to follow-up. Mean log DNA was 7.67 at the start which after starting entecavir reduced to 4.1, 2.8, 1.19, 1.09, and 0.84 at 12, 24, 48, 72, and 96 weeks, respectively (P value < 0.0001). Mean ALT decreased from 332.5 which reduced to 190, 115, 63, and 46 at 4, 12, 24, and 48 weeks, respectively (P < 0.0001). 67.7% achieved the primary outcome and had undetectable DNA at 48 weeks which increased to 26 (83.9%) at 96 weeks. At 48 weeks, 80.6% patients achieved ALT normalization. Thirty percent developed HBeAg seroconversion. Two patients developed virological breakthrough, one at 96 weeks and another at 192 weeks. No significant adverse effects were observed.

CONCLUSION

Entecavir is safe and effective in long term for the treatment of hepatitis B in immunocompromised children.

Present and Future Therapies for Chronic Hepatitis B

Chronic hepatitis B (CHB) remains the leading cause of liver-related morbidity and mortality across the world. If left untreated, approximately one-third of these patients will progress to severe end-stage liver diseases including liver failure, cirrhosis, and hepatocellular carcinoma (HCC). High level of serum HBV DNA is strongly associated with the development of liver failure, cirrhosis, and HCC. Therefore, antiviral therapy is crucial for the clinical management of CHB. Current antiviral drugs including nucleoside/nucleotide analogues (NAs) and interferon-α (IFN-α) can suppress HBV replication and reduce the progression of liver disease, thus improving the long-term outcomes of CHB patients. This chapter will discuss the standard and optimization antiviral therapies in treatment-naïve and treatment-experienced patients, as well as in the special populations. The up-to-date advances in the development of new anti-HBV agents will be also discussed. With the combination of the current antiviral drugs and the newly developed antiviral agents targeting the different steps of the viral life cycle or the newly developed agents modulating the host immune responses, the ultimate eradication of HBV will be achieved in the future.

Updates in the management of hepatitis B in children

Introduction: Universal infant hepatitis B virus (HBV) vaccination program has reduced HBV infection dramatically in vaccinated young generations. Management of chronically infected children is still challenging concerning high viral load with mostly mild diseases, yet with a nonnegligible proportion of advanced diseases, and long-term effect of antivirals. However, with more potent antivirals approved for pediatric patients, to start antivirals earlier in eligible patients may benefit their outcomes. This review aimed to update the current management of chronic hepatitis B in children.Areas covered: This review covered the natural history of chronic HBV infection, management of chronic hepatitis B in children from the past to the present, current consensus on the treatment of chronic hepatitis B in children, controversies in cessation of oral antivirals, and management of special populations such as pregnancy and co-infections.Expert opinions: Without contraindication, peginterferon is recommended for immune-active children ≥ 3 years old. For those intolerant, decompensating or preferring oral therapy, first-line Nucleos(t)ide analogs (NUC), Entecavir or Tenofovir, may be applied. For immune-tolerant or inactive carriers, close monitoring is crucial. When to stop NUCs and novel therapies for HBV cure await further research.

Long-term efficacy and safety of peginterferon in the treatment of children with HBeAg-positive chronic hepatitis B

Achieving 'clinical cure' in children with chronic hepatitis B (CHB) with safe and effective antiviral treatment is an unmet medical need. Peginterferon (PegIFN) has higher hepatitis B s antigen (HBsAg) clearance than nucleoside analogs (NUC). Currently, studies on interferon (IFN) in the treatment of Chinese children with CHB are relatively rare. This study aimed to further explore the efficacy of PegIFNα-2a as an antiviral treatment in Chinese children and analyse the long-term follow-up after drug discontinuation. We enrolled 118 patients with CHB (2-16 years old, 79 cases are males) treated with PegIFNα-2a by the author in the Third People's Hospital of Kunming City from February 2009 to February 2015. The course of treatment was 52 weeks, with a follow-up period of 104 weeks. All the patients completed at least 1 dose, of which 104 completed at least 36 weeks of treatment and 104 weeks of follow-up. During treatment and follow-up, indicators such as alanine aminotransferase (ALT), hepatitis B virus (HBV) DNA and HBV serological markers were monitored, and the efficacy and safety of PegIFNα-2a in the treatment of CHB patients were observed. Hepatitis B e antigen (HBeAg) clearance and seroconversion rates were 53.8% and 49%, respectively, when the drug was discontinued; 72.1% and 72.1%, respectively, at the end of the follow-up; and 98.2% and 98%, respectively, for sustained response. HBsAg clearance and seroconversion rates were 48.1% and 47.1%, respectively, when the drug was discontinued; 53.8% and 52.9%, respectively, at the end of the follow-up; and 94% and 95.9%, respectively, for sustained response. The HBV DNA suppression rate was 89.4% when the drug was discontinued, 90.4% at the end of the follow-up and 97.8% for sustained response. Two patients had virological relapse (2.3%) during follow-up; however, no clinical relapse occurred. Multivariate regression analysis showed that genotype B, weight < 25 kg or between 25 and 45 kg, and reduction of HBsAg by more than 1 log following 24 weeks of treatment were independent predictors of HBsAg clearance at the end of follow-up. Adverse events that occurred during treatment were similar to those reported in previous clinical studies on PegIFN. The results of this study showed that PegIFN was safe and effective in the treatment of children with CHB, and sustained response could be achieved after treatment. PegIFN treatment of children with CHB helps more achieve 'clinical cure'.

Hepatitis B virus infection in children and adolescents

Hepatitis B virus (HBV) infection is a major cause of acute and chronic liver disease and associated morbidity and mortality worldwide. Vertical (mother-to-child) and horizontal early childhood transmission are the main routes of HBV transmission and are responsible for most chronic infections, including among adults who bear the greatest burden of morbidity and mortality. Universal hepatitis B immunisation at birth and in infancy is the key strategy for global elimination of HBV infection, and has been highly effective in reducing new vertical infections. However, global progress in scale-up of HBV testing and treatment has been slow in adults and children. In this Series paper, we summarise knowledge on the epidemiology, natural history, and treatment of chronic HBV infection in adolescents and children, and we highlight key differences from HBV infection in adults. The estimated global prevalence of HBV infection in children aged 5 years or younger is 1·3%. Most children are in the high-replication, low-inflammation phase of infection, with normal or only slightly raised aminotransferases; cirrhosis and hepatocellular carcinoma are rare. Although entecavir is approved and recommended for children aged 2-17 years, and tenofovir for those aged 12-18 years, a conservative approach to treatment initiation in children is recommended. Key actions to address current policy gaps include: validation of non-invasive tests for liver disease staging; additional immunopathogenesis studies in children with HBV infection; long-term follow-up of children on nucleoside or nucleotide analogue regimens to inform guidance on when to start treatment; evaluation of different treatment strategies for children with high rates of HBV replication; and establishment of paediatric treatment registries and international consortia to promote collaborative research.

Management of Hepatitis B Virus Infection: 2018 Guidelines from the Canadian Association for the Study of Liver Disease and Association of Medical Microbiology and Infectious Disease Canada

Hepatitis B virus (HBV) infection is an important public health problem in Canada. In keeping with evolving evidence and understanding of HBV pathogenesis, the Canadian Association for the Study of Liver Disease periodically publishes HBV management guidelines. The goals of the 2018 guidelines are to (1) highlight the public health impact of HBV infection in Canada and the need to improve diagnosis and linkage to care, (2) recommend current best-practice guidelines for treatment of HBV, (3) summarize the key HBV laboratory diagnostic tests, and (4) review evidence on HBV management in special patient populations and include more detail on management of HBV in pediatric populations. An overview of novel HBV tests and therapies for HBV in development is provided to highlight the recent advances in HBV clinical research. The aim and scope of these guidelines are to serve as an up-to-date, comprehensive resource for Canadian health care providers in the management of HBV infection.

Taiwan consensus statement on the management of chronic hepatitis B

The experts of Taiwan Association for the Study of Liver (TASL) have actively participated and led the guidelines on hepatitis B virus (HBV) management by Asian Pacific Association for the Study of Liver (APASL) which is the first international association for the study of liver to publish the statement on HBV management before. However, there are more and more new data on the natural history and treatment of HBV infection in the past decade. These include new application of an old biomarker (quantitative HBsAg), clinical significance of HBV genotype and naturally occurring mutations, the role of non-invasive examination in evaluating severity of hepatic fibrosis, clinical significance of outcome calculators, new drug or new combination strategies towards more effective therapy and organ transplantation including liver and non-liver transplantation. It is time to publish the guidelines on HBV management of Taiwan. Hence, TASL have conducted an expert meeting to review, to discuss and to debate the relevant literatures, followed by draft the manuscript of HBV management guidelines and recommendations. The 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, patient receiving immune suppression or chemotherapy and patients in the setting of liver transplantation and hepatocellular carcinoma, are also included.

INASL Guidelines on Management of Hepatitis B Virus Infection in Patients receiving Chemotherapy, Biologicals, Immunosupressants, or Corticosteroids

Hepatitis B Virus (HBV) reactivation in patients receiving chemotherapy, biologicals, immunosupressants, or corticosteroids is emerging to be an important cause of morbidity and mortality in patients with current or prior exposure to HBV infection. These patients suffer a dual onslaught of illness: one from the primary disease for which they are receiving the culprit drug that led to HBV reactivation, and the other from HBV reactivation itself. The HBV reactivation not only leads to a compromised liver function, which may culminate into hepatic failure; it also adversely impacts the treatment outcome of the primary illness. Hence, identification of patients at risk of reactivation before starting these drugs, and starting treatment aimed at prevention of HBV reactivation is the best strategy of managing these patients. There are no Indian guidelines on management of HBV infection in patients receiving chemotherapy, biologicals, immunosupressants, or corticosteroids for the treatment of rheumatologic conditions, malignancies, inflammatory bowel disease, dermatologic conditions, or solid-organ or bone marrow transplantation. The Indian National Association for Study of the Liver (INASL) had set up a taskforce on HBV in 2016, with a mandate to develop consensus guidelines for management of various aspects of HBV infection, relevant to India. In 2017 the taskforce had published the first INASL guidelines on management of HBV infection in India. In the present guidelines, which are in continuation with the previous guidelines, the issues on management of HBV infection in patients receiving chemotherapy, biologicals, immunosupressants, or corticosteroids are addressed.

Efficacy and Safety of Peginterferon Alfa-2a (40KD) in Children With Chronic Hepatitis B: The PEG-B-ACTIVE Study

Children with chronic hepatitis B (CHB) represent an area of unmet medical need, attributed to increased lifetime risk of CHB sequelae and limited therapeutic options compared with adult CHB patients. The PEG-B-ACTIVE (NCT01519960) phase III study evaluated peginterferon (PegIFN) alfa-2a treatment in children aged 3 to <18 years with CHB. A total of 161 hepatitis B e antigen (HBeAg)-positive immune-active patients without advanced fibrosis (AF)/cirrhosis were randomized (2:1) to PegIFN alfa-2a (Group A, n = 101) or no treatment (Group B, n = 50); patients with AF were assigned to PegIFN alfa-2a (Group C, n = 10). PegIFN alfa-2a was administered for 48 weeks by body surface area (BSA) category, based on 180 μg/1.73 m² . HBeAg seroconversion rates at 24 weeks posttreatment were significantly higher in Group A (25.7% vs. 6%; P = 0.0043), as were the rates of hepatitis B surface antigen (HBsAg) clearance (8.9% vs. 0%; P = 0.03), hepatitis B virus (HBV) DNA <2,000 IU/mL (28.7% vs. 2.0%; P < 0.001) or undetectable (16.8% vs. 2.0%; P = 0.0069), and alanine aminotransferase (ALT) normalization (51.5% vs. 12%; P < 0.001). Safety, including incidence of ALT flares and neutropenia, was comparable to the established PegIFN alfa-2a profile in HBV-infected adults or hepatitis C virus-infected children. Changes in growth parameters were minimal during treatment and comparable to those in untreated patients. Safety and efficacy outcomes in Group C were in line with Group A. Conclusion: PegIFN alfa-2a treatment of children in the immune-active phase of CHB was efficacious and well tolerated, and associated with higher incidence of HBsAg clearance than in adults. This represents an important advance to the treatment options for children with CHB.

Pegylated interferon-based sequential therapy for treatment of HBeAg reactive pediatric chronic hepatitis B-First study in children

BACKGROUND

Our aim was to evaluate the efficacy and safety of sequential therapy using pegylated interferon (Peg-IFN) and nucleos(t)ide analogue (NA) for treatment of children in immunoactive (IA) and immunotolerant (IT) phases of chronic hepatitis B.

METHODS

It was a prospective observational study where those willing for sequential therapy were allocated to group 1 (sequential therapy) and others to group 2 (standard therapy). Sequential therapy included 8 weeks of NA followed by 44 weeks of combination of NA and Peg-IFN. In group 2, IA children received NA monotherapy, and IT children received no therapy. HBe seroconversion, HBs seroconversion, and loss of HBV DNA were the major outcome measures.

RESULTS

A total of 61 children (36 IA and 25 IT) were included in the analysis. Among the IA children, 17 received sequential therapy and 19 received standard therapy; whereas, among the IT children, 12 received sequential therapy and 13 did not receive any therapy. In IA phase, sequential therapy led to higher HBe seroconversion (64.7% vs. 21.05%, p = 0.017) and higher virological clearance (94.12% vs. 52.63%, p = 0.008). In IT children, there was no benefit of treatment with sequential therapy over observation alone. Baseline ALT > 100 IU/L predicted response to therapy with 100% sensitivity, 89.5% specificity, and LR⁺ of 9.52.

CONCLUSION

Sequential therapy leads to higher HBe seroconversion and virological response in children in IA phase. Children with baseline ALT > 100 IU/mL are more likely to respond to sequential therapy. There appears to be no role of sequential therapy in children in IT phase.

The Health Care Transition of Youth With Liver Disease Into the Adult Health System: Position Paper From ESPGHAN and EASL

BACKGROUND

Medical advances have dramatically improved the long-term prognosis of children and adolescents with once-fatal hepatobiliary diseases. However, there is no generally accepted optimal pathway of care for the transition from paediatric care to the adult health system.

AIM

The purpose of this position paper is to propose a transition process for young people with paediatric onset hepatobiliary diseases from child-centred to adult-centred healthcare services.

METHODS

Seventeen ESPGHAN/EASL physicians from 13 countries (Austria, Belgium, France, Germany, Hungary, Italy, the Netherlands, Norway, Poland, Spain, Sweden, Switzerland, and United Kingdom) formulated and answered questions after examining the currently published literature on transition from childhood to adulthood. PubMed and Google Scholar were systematically searched between 1980 and January 2018. Quality of evidence was assessed by the Grading of Recommendation Assessment, Development and Evaluation (GRADE) system. Expert opinions were used to support recommendations whenever the evidence was graded weak. All authors voted on each recommendation, using the nominal voting technique.

RESULTS

We reviewed the literature regarding the optimal timing for the initiation of the transition process and the transfer of the patient to adult services, principal documents, transition multi-professional team components, main barriers, and goals of the general transition process. A transition plan based on available evidence was agreed focusing on the individual young people's readiness and on coordinated teamwork, with transition monitoring continuing until the first year of adult services.We further agreed on selected features of transitioning processes inherent to the most frequent paediatric-onset hepatobiliary diseases. The discussion highlights specific clinical issues that will probably present to adult gastrointestinal specialists and that should be considered, according to published evidence, in the long-term tracking of patients.

CONCLUSIONS

Transfer of medical care of individuals with paediatric onset hepatobiliary chronic diseases to adult facilities is a complex task requiring multiple involvements of patients and both paediatric and adult care providers.

INASL Position Statements on Prevention, Diagnosis and Management of Hepatitis B Virus Infection in India: The Andaman Statements

Hepatitis B Virus (HBV) infection is one of the major causes of morbidity, mortality and healthcare expenditure in India. There are no Indian consensus guidelines on prevention, diagnosis and management of HBV infection. The Indian National Association for Study of the Liver (INASL) set up a taskforce on HBV in 2016, with a mandate to develop consensus guidelines for diagnosis and management of HBV infection, relevant to disease patterns and clinical practices in India. The taskforce first identified contentious issues on various aspects of HBV management, which were allotted to individual members of the taskforce who reviewed them in detail. A 2-day round table discussion was held on 11th and 12th February 2017 at Port Blair, Andaman & Nicobar Islands, to discuss, debate, and finalize the consensus statements. The members of the taskforce reviewed and discussed the existing literature threadbare at this meeting and formulated the 'INASL position statements' on each of the issues. The evidence and recommendations in these guidelines have been graded according to the Grading of Recommendations Assessment Development and Evaluation (GRADE) system with minor modifications. The strength of recommendations (strong: 1, weak: 2) thus reflects the quality (grade) of underlying evidence (A, B, C, D). We present here the INASL position statements on prevention, diagnosis and management of HBV in India.

Potential kidney toxicity from the antiviral drug tenofovir: new indications, new formulations, and a new prodrug

PURPOSE OF REVIEW

The antiviral agent tenofovir is highly effective for the treatment of HIV and hepatitis B virus infections, and the older prodrug tenofovir disoproxil fumarate (TDF) is also a component of daily preexposure prophylaxis (PrEP) to reduce the risk of HIV infection in high-risk populations. Although TDF is well tolerated, the potential for kidney and bone toxicity has important implications for public health given the large number of individuals exposed to TDF worldwide. This review summarizes the recent literature on kidney and bone health in individuals treated with TDF and the newer prodrug tenofovir alafenamide (TAF).

RECENT FINDINGS

Risk factors for TDF toxicity appear to be similar in patients treated for HIV or hepatitis B virus and in HIV-uninfected PrEP users, although drug-drug interactions are a more important concern in HIV-positive individuals. The risk of toxicity appears to be lower with TAF, but further studies are needed to confirm the safety of long-term use and to evaluate the efficacy of TAF-based PrEP.

SUMMARY

Nephrologists should be aware of the potential kidney and bone toxicity of TDF, as well as unique situations in which the newer prodrug TAF may contribute to kidney injury.

Antiviral Efficacy of Tenofovir Monotherapy in Children with Nucleos(t)ide-naive Chronic Hepatitis B

BACKGROUND

The purpose was to compare the efficacy between tenofovir disoproxil fumarate (TDF) and lamivudine (LMV) in children with nucleos(t)ide-naive chronic hepatitis B (CHB) infection. Patients with CHB were treated with TDF in the immune-reactive phase and compared with a historical control group of patients treated with LMV before the TDF era.

METHODS

Hepatitis B virus (HBV) DNA titer decrements (> 3 log₁₀ IU/mL) were monitored after treatment initiation. The treatment duration for HBV DNA clearance (< 357 IU/mL) and complete response (HBeAg loss and HBV DNA clearance) were analyzed. The follow-up period was 96 weeks.

RESULTS

Sixteen patients were treated with TDF and compared with a historical control group of 24 patients treated with LMV. HBV DNA decrement (> 3 log₁₀ IU/mL) was achieved in 100% (16/16) of the TDF group but in only 62.5% (15/24) of the LMV group (P = 0.005) at 48 weeks. The HBV DNA clearance (< 357 IU/mL) in the TDF and LMV groups was, respectively, as follows: 62.5% (10/16) and 25.0% (6/24) at 12 weeks (P = 0.018), 81.3% (13/16) and 37.5% (9/24) at 24 weeks (P = 0.006), 93.8% (15/16) and 50.0% (12/24) at 48 weeks (P = 0.004), and 100% (16/16) and 54.2% (13/24) at 96 weeks (P = 0.001). Complete response occurred in 41.7% (5/12) of HBeAg-positive patients in the TDF group and 28.6% (6/21) of the LMV group at 96 weeks (P = 0.443).

CONCLUSION

TDF monotherapy for 96 weeks produced a significantly more effective virologic response than LMV monotherapy in children with nucleos(t)ide-naive CHB.

Early Onset of Tenofovir-Related Fanconi Syndrome in a Child with Acute Hepatitis B: A Case Report and Systematic Review of Literature

Tenofovir disoproxil fumarate- (TDF-) related nephropathy is known to be a long-term complication of this drug, more commonly observed in HIV-infected patients, but occurring also in hepatitis B. Cases of Fanconi Syndrome associated with TDF have been reported in adult patients, usually as a long-term complication of chronic hepatitis B treatment. We present here a case of a 12-year-old male developing a severe acute HBV hepatitis treated with TDF. The patient achieved an early virological and biochemical response, but with a subsequent onset of proximal renal tubular damage, consistent with Fanconi Syndrome. After withdrawing this drug and switching to Entecavir, a complete resolution of tubulopathy and, after 6 months, a complete HBsAg seroconversion occurred. To our knowledge, this is the first report of an early renal injury due to TDF-therapy in a pediatric patient treated for acute hepatitis B.

EASL 2017 Clinical Practice Guidelines on the management of hepatitis B virus infection

Hepatitis B virus (HBV) infection remains a global public health problem with changing epidemiology due to several factors including vaccination policies and migration. This Clinical Practice Guideline presents updated recommendations for the optimal management of HBV infection. Chronic HBV infection can be classified into five phases: (I) HBeAg-positive chronic infection, (II) HBeAg-positive chronic hepatitis, (III) HBeAg-negative chronic infection, (IV) HBeAg-negative chronic hepatitis and (V) HBsAg-negative phase. All patients with chronic HBV infection are at increased risk of progression to cirrhosis and hepatocellular carcinoma (HCC), depending on host and viral factors. The main goal of therapy is to improve survival and quality of life by preventing disease progression, and consequently HCC development. The induction of long-term suppression of HBV replication represents the main endpoint of current treatment strategies, while HBsAg loss is an optimal endpoint. The typical indication for treatment requires HBV DNA >2,000IU/ml, elevated ALT and/or at least moderate histological lesions, while all cirrhotic patients with detectable HBV DNA should be treated. Additional indications include the prevention of mother to child transmission in pregnant women with high viremia and prevention of HBV reactivation in patients requiring immunosuppression or chemotherapy. The long-term administration of a potent nucleos(t)ide analogue with high barrier to resistance, i.e., entecavir, tenofovir disoproxil or tenofovir alafenamide, represents the treatment of choice. Pegylated interferon-alfa treatment can also be considered in mild to moderate chronic hepatitis B patients. Combination therapies are not generally recommended. All patients should be monitored for risk of disease progression and HCC. Treated patients should be monitored for therapy response and adherence. HCC remains the major concern for treated chronic hepatitis B patients. Several subgroups of patients with HBV infection require specific focus. Future treatment strategies to achieve 'cure' of disease and new biomarkers are discussed.

Tolerance and immunity to pathogens in early life: insights from HBV infection

Immunity is not static but varies with age. The immune system of a newborn infant is not "defective" or "immature." Rather, there are distinct features of innate and adaptive immunity from fetal life to adulthood, which may alter the susceptibility of newborn infants to infections compared to adults. Increased protection to certain infectious diseases during early life may benefit from a dampened immune response as a result of decreased immune pathology. This concept may offer an alternative interpretation of the different pathological manifestations clinically observed in hepatitis B virus (HBV)-infected patients during the natural history of infection. Herein, we review the immune pathological features of HBV infection from early life to adulthood and challenge the concept of a generic immune tolerant state in young people. We then discuss how the different clinical and virological manifestations during HBV infection may be related to the differential antiviral immunity and pro-inflammatory capacity generated at different ages. Lastly, we address the potential to consider earlier therapeutic intervention in HBV-infected young patients to achieve effective immune control leading to better outcomes.

Hepatitis B: changing epidemiology and interventions

Hepatitis B virus infection is still a major public health problem worldwide, since more than 350 million people have chronic, lifelong infection and nearly 1 million deaths occur each year owing to complications. Most infections are acquired at birth or during early childhood. Nowadays, low- and middle-income countries bear the majority of the burden of hepatitis B-related liver cancer deaths despite the availability of an effective vaccine and antiviral treatments. In this review the epidemiology, strategies of prevention and the recent advances in therapy, genotype diversity and resistance are discussed.

Hepatitis B and C

Chronic viral hepatitis is a global health threat and financial burden. Hepatitis B and C viruses (HBV and HCV) are the most common causes of chronic viral hepatitis in the United States. Most cases are asymptomatic before adulthood. Research has resulted in effective therapy for HCV and the promise of effective therapies for HBV. For HCV, therapy is pegylated interferon and ribavirin. Clinical trials with effective direct-acting antiviral agents are underway in pediatrics. For HBV, approved agents are alpha-interferon, lamivudine, adefovir, tenofovir, and entecavir. However, treatment seldom results in functional cure and more effective therapies are urgently needed.

Recommendations for the treatment of hepatitis B in 2017

The therapeutic goal which is currently unfrequent but realistic in HBV infected patients is sustained HBsAg clearance. It is preceded by the loss or significant suppression of HBV replication and leads to inhibition of the progression of liver fibrosis, normalization of biochemical indicators of liver damage, reduction in the risk of hepatocellular carcinoma, prolongation of survival, prevention of HBV infection in the transplanted organ in post-transplant patients, enhancement of the quality of life, inhibition or reversal of extrahepatic changes associated with HBV infection, and halting of the spread of HBV infections. Recommendations of Polish Group of Experts for HBV for 2017 provide guidelines to assess treatment eligibility, choice of the first-line drug, monitoring and duration of treatment, management of treatment failure as well as therapy of HBV associated cirrhosis or hepatocellular carcinoma. Moreover it contains advice for treatment of HBV infection in children, females planning pregnancy or pregnant. We also included recommendations for pre- and post-exposure prophylaxis, prevention of HBV transmission from mother to infant, after liver transplantation, on immunosuppressive therapy and during HCV treatment.

Response to Tenofovir Among Lamivudine-experienced Hepatitis B and HIV-coinfected Adolescents

We determined hepatitis B virus (HBV) suppression rates among 18 lamivudine (3TC)-experienced HBV-human immunodeficiency virus-coinfected adolescents after treatment with tenofovir disoproxil fumurate (TDF). At TDF initiation, their median age was 17.6 years, and duration of 3TC exposure was 7.3 years. Eleven patients (61%) achieved HBV DNA <60 IU/mL after 48 weeks on TDF and 3TC which was similar to adult studies, although hepatitis B surface antigen loss or hepatitis B envelope antigen seroconversion did not occur.

Vitamin E for the treatment of children with hepatitis B e antigen-positive chronic hepatitis: A systematic review and meta-analysis

AIM

To assess vitamin E efficacy, defined as its ability to induce hepatitis B e antigen (HBeAg) seroconversion, in children with HBeAg-positive persistent hepatitis.

METHODS

In July 2016, we extracted articles published in MEDLINE and the Cochrane Library using the following search terms: “chronic hepatitis B”, “children”, “childhood”, “therapy”, “treatment”, “vitamin E”, “tocopherols”, “tocotrienols”. Only randomized controlled trials (RCTs) published in English language were collected.

RESULTS

Three RCTs met inclusion criteria and were considered in the present meta-analysis. Overall, 23/122 children in the treatment group underwent HBeAg seroconversion vs 3/74 in the control group (OR = 3.96, 95%CI: 1.18-13.25, P = 0.025).

CONCLUSION

Although our meta-analysis has several limits, including the very small number of available studies and enrolled children with HBeAg positivity-related hepatitis, it suggests that vitamin E use may enhance the probability to induce HBeAg seroconversion in these patients. Further well designed and adequately sized trials are required to confirm or deny these very preliminary results.

Chronic hepatitis B in children: Therapeutic challenges and perspectives

Chronic hepatitis B virus (HBV) infection and HBV-related hepatitis in children remains an unmet medical need, as current treatments are only partially effective, and only in a limited number of affected children. So-called "immunotolerant" children have not shown increased serological responses to available treatments. In cases involving more active disease, serological response has only been obtained in approximately one-third of patients when using interferon, while other cases exhibited virological response solely under continuous treatment with nucleoside analogs. Guidelines have recently been established to aid pediatricians in effectively managing this condition. With the available medications, no treatment is so far indicated for immunotolerant children, but only for cases presenting increased alanine aminotransferase levels to over 1.5-2 times the upper limit of normal for over 6 months, and without spontaneous HB envelope antigen to antibody seroconversion. The therapeutic arsenal approved by the Food and Drugs Administration and European Medicines Agency for children remains limited because of the lack of large-scale clinical trials validating treatments already approved for the adult population. Yet, the recent discovery of a specific HBV-cell surface receptor, NTCP, allows for new treatment perspectives regarding the future.

Pediatric hepatitis B treatment

Although the introduction of hepatitis B vaccine has been contributing to the reduction in the prevalence of hepatitis B virus (HBV) carriers worldwide, the treatment of children with chronic HBV infection is a challenge to be addressed. HBeAg seroconversion, which induces low replication of HBV, is widely accepted as the first goal of antiviral treatment in children with chronic hepatitis B. However, spontaneous HBeAg seroconversion is highly expected in children with chronic HBV infection. Therefore, the identification of children who need antiviral treatment to induce HBeAg seroconversion is essential in the management of chronic HBV infection. Guidelines and experts' opinion show how to identify children who should be treated and how to treat them. If decompensated cirrhosis is absent, interferon-alpha is the first-line antiviral treatment. Nucleos(t)ide analogues (NAs), such as lamivudine, adefovir, entecavir and tenofovir, are also available for the treatment of children, although the approval age differs among them. If decompensated cirrhosis is present, NAs are the first-line antivirals. When the emergence of drug-resistant HBV variants is taken into consideration, entecavir (approved for age 2 years or older) and tenofovir (age 12 years or older), which have high genetic barriers, will play a central role in the treatment of HBV infection. However, the optimal duration of NA treatment and adverse events of long-term NA treatment remain unclear in children. In resource-constrained countries and regions, the financial burden of visiting hospitals, receiving routine blood examination and purchasing antiviral drugs is heavy. Moreover, there is no clear evidence that the induction of HBeAg seroconversion by antiviral treatment prevents the progression of liver disease to cirrhosis and hepatocellular carcinoma in children with chronic HBV infection. It is thus imperative to clarify the clinical impact of antiviral treatment in children with HBV infection.

Pediatric liver diseases: current challenges and future perspectives

Chronic liver diseases in children represent a rising problem with significant effects on public health. In fact, several pediatric liver diseases are precursors of adult chronic hepatopathies, cirrhosis and hepatocellular carcinoma. The prevalence of liver diseases in children is unknown. In the USA, every year, 15,000 children are hospitalized for liver diseases, but these disorders continue to be under-recognized or diagnosed late. The main reason is due to the frequent absence of symptoms in the vast majority of liver diseases, especially in the early stages. In the last few decades several advances have been made in understanding the pathogenesis of liver diseases, permitting the discovery of new therapeutic targets to treat liver diseases, thus improving the natural history of these disorders. In this article we discuss the most recent advances in the understanding of the pathogenesis, diagnosis and treatment of the most frequent pediatric liver diseases.

Hepatitis B immunity in the pediatric liver transplant population

PURPOSE OF REVIEW

Hepatitis B virus (HBV) infection contributes significantly to vaccine-preventable disease related deaths, and insufficient HBV immunity may have unique implications for the pediatric liver transplant population. This article reviews the significance of HBV infection and the vaccination and screening measures needed to achieve adequate HBV immunity in these children.

RECENT FINDINGS

HBV non-immunity among transplant candidates is higher than expected, even after appropriate completion of the vaccine series. Annual measurement of quantifiable HBV surface antibody in this vulnerable group should guide administration of booster and/or re-vaccination, improving immunoprotection from this potentially deadly hepatotropic virus. The liver plays a vital role in immune regulation; it induces immune tolerance and competence and both clears antigens from the circulation and generates liver-primed memory cells through antigen presentation via hepatic scavenger cells. Lymphocyte populations are depleted in patients with liver disease.

SUMMARY

Immunity provided during early childhood against HBV infection is important to both pediatric liver transplant candidates and aging recipients. Appropriate vaccination and achievement of adequate immunity pre-transplant and post-transplant is critical. The field of pediatric transplantation is ripe for functional cellular and humoral immunity studies that examine factors which predict poor immune response to childhood vaccines, particularly HBV.

Tenofovir in treatment of Iranian patients with chronic hepatitis B virus infection: An open-label case series

OBJECTIVE

Tenofovir is among the first-line treatments for chronic hepatitis B (CHB) virus infection. We evaluated the efficacy and safety of Tenofovir in treatment of Iranian patients with CHB.

METHODS

Forty treatment-native patients with CHB but without concurrent hepatitis C or human immunodeficiency virus infections were treated with Tenobiovir(™) 300 mg/day. The hepatitis B virus (HBV) DNA load, hepatitis B e antigen (HBe Ag), anti-hepatitis B e antibody (HBe Ab), liver enzymes, and creatinine were measured before and at least 3 months after the treatment.

FINDINGS

The mean age of patients was 38.1 ± 12.4 years and 65% of them were male. Seventeen (42.5%) patients were HBe Ag-positive and 15 (37.5%) patients had alanine aminotransferase (ALT) of two times above the normal. The HBV DNA load was significantly decreased after the treatment (P < 0.001). Twenty-seven (67.5%) patients had viral load of ≤2000 IU/ml and 22 (55%) patients had undetectable HBV DNA level after the treatment. Among positive HBe Ag patients, the HBe Ag became negative in 15 (88.2%) patients after the treatment and HBe Ab became positive in 3 (17.6%) patients. Liver enzymes' levels were significantly decreased after the treatment (P <0.05) and ALT transaminase level became normalized in 86.7% (13 out of 15) of cases with baseline levels twice the normal.

CONCLUSION

Treatment response rate to Tenofovir in Iranian patients with CHB was high. The virological and serological response rate and safety of Tenofovir in our population was comparable to other populations. Considering availability and costs, Tenobiovir(™) could be recommended as the first-line therapy of chronic HBV infection in Iran.

Review article: long-term safety of nucleoside and nucleotide analogues in HBV-monoinfected patients

BACKGROUND

Nucleos(t)ide analogues (NUCs) for chronic hepatitis B treatment achieve high rates of viral suppression and are generally well tolerated. Entecavir (ETV) and tenofovir disoproxil fumarate (TDF) are the currently preferred first-line agents. The safety of these agents in clinical practice is particularly relevant since long-term treatment is usually required.

AIM

To summarise and critically discuss recent real-world evidence on the safety of treatment with ETV or TDF in hepatitis B virus (HBV)-monoinfected patients.

METHODS

PubMed and conference proceedings up to 15th June 2015 were searched using the terms ((((Hepatitis_B) OR HBV) AND ((tenofovir) OR entecavir)) AND (((lactic_acidosis) OR bone) OR renal)).

RESULTS

In selected populations included in registration studies, both ETV and TDF were well tolerated with no clinically significant renal toxicity or lactic acidosis. Growing 'real-world' clinical experience with these agents includes some reports of ETV-associated lactic acidosis and TDF-associated renal impairment; however, evidence from cohort studies appears to be conflicting. In the case of ETV-related lactic acidosis, a small number of cases have been reported, all in patients with decompensated cirrhosis. The degree of association between TDF treatment and changes in markers of renal function varies between studies: discrepancies may result from the use of different definitions and cut-offs for reporting renal toxicities, and differences in patient populations.

CONCLUSIONS

Pre-treatment and on-treatment monitoring of eGFR and phosphorus, with prompt appropriate dose adjustment or treatment switch can minimise the impact of NUC renal toxicity. Standardisation of measures of renal impairment and identification of early molecular markers remain an unmet need.

Current treatments for chronic hepatitis B virus infections

Over 240 million people worldwide are chronically infected with hepatitis B virus (HBV) and although a prophylactic vaccine and effective antiviral therapies are available, no cure exists. Curative regimens are urgently needed because up to one million deaths per year are caused by HBV-related liver cancer and end-stage liver disease. HBV is an hepatotropic virus which belongs to the Hepadnaviridae family and replicates its DNA genome via a reverse transcriptase mechanism. Effective therapies have been developed for chronic hepatitis B (CHB) infection in the last two decades. They rely on the use of interferon alpha and its pegylated formulation, and on nucleos(t)ide analogs that inhibit viral polymerase activity. Their results are discussed in this review as well as future perspectives.

Randomized, controlled trial of entecavir versus placebo in children with hepatitis B envelope antigen-positive chronic hepatitis B

This ongoing, randomized phase III study assesses the safety and efficacy of entecavir versus placebo in nucleos(t)ide-naïve children (2 to <18 years) with hepatitis B envelope antigen (HBeAg)-positive chronic hepatitis B (CHB). Blinded treatment was administered for a minimum of 48 weeks. After week 48, patients with HBeAg seroconversion continued blinded treatment; those without switched to open-label entecavir. The primary endpoint was HBeAg seroconversion and HBV DNA <50 IU/mL at week 48. A total of 180 patients were randomized (2:1) and treated. Baseline median age was 12 years, with approximately 50% of children ages >12 to <18, and 25% each ages ≥2 to ≤6 and >6 to ≤12. Rates for the primary endpoint at week 48 were significantly higher with entecavir than placebo (24.2% [29 of 120] vs. 3.3% [2 of 60]; P = 0.0008). Furthermore, higher response rates were observed with entecavir compared with placebo for the key week 48 secondary endpoints: HBV DNA <50 IU/mL (49.2% [59 of 120] vs. 3.3% [2 of 60]; P < 0.0001); alanine aminotransferase normalization (67.5% [81 of 120] vs. 23.3% [14 of 60]; P < 0.0001); and HBeAg seroconversion (24.2% [29 of 120] vs. 10.0% [6 of 60]; P = 0.0210). Among entecavir-randomized patients, there was an increase in all efficacy endpoints between weeks 48 and 96, including an increase from 49% to 64% in virological suppression. The cumulative probability of emergent entecavir resistance through years 1 and 2 of entecavir was 0.6% and 2.6%, respectively. Entecavir was well tolerated with no observed differences in adverse events or changes in growth compared with placebo.

CONCLUSION

In childhood CHB, entecavir demonstrated superior antiviral efficacy to placebo with a favorable safety profile. These results support the use of entecavir as a therapeutic option in children and adolescents with CHB.

Antiviral therapy in management of chronic hepatitis B viral infection in children: A systematic review and meta-analysis

Most individuals with chronic hepatitis B viral (HBV) infection acquired the infection around the time of birth or during early childhood. We aimed to synthesize evidence regarding the effectiveness of antiviral therapy in the management of chronic HBV infection in children. We conducted a comprehensive search of multiple databases from 1988 to December 2, 2014, for studies that enrolled children (<18 years) with chronic HBV infection treated with antiviral therapy. We included observational studies and randomized controlled trials (RCTs). Two independent reviewers selected studies and extracted data. In the 14 included studies, two cohort studies showed no significant reduction in the already low risk of hepatocellular carcinoma or cirrhosis and 12 RCTs reported intermediate outcomes. In RCTs with posttreatment follow-up <12 months, antiviral therapy compared to placebo improved alanine aminotransferase normalization (risk ratio [RR] = 2.3, 95% confidence interval [CI] 1.7-3.2), hepatitis B e antigen (HBeAg) clearance/loss (RR = 2.1, 95% CI 1.5-3.1), HBV DNA suppression (RR = 2.9, 95% CI 1.8-4.6), HBeAg seroconversion (RR = 2.1, 95% CI 1.4-3.3), and hepatitis B surface antigen clearance (RR = 5.8, 95% CI 1.1-31.5). In RCTs with posttreatment follow-up ≥12 months, antiviral therapy improved cumulative HBeAg clearance/loss (RR = 1.9, 95% CI 1.7-3.1), HBeAg seroconversion (RR = 2.1, 95% CI 1.3-3.5), alanine aminotransferase normalization (RR = 1.4, 95% CI 1.1-1.7), and HBV DNA suppression (RR = 1.4, 95% CI 1.1-1.8) but not hepatitis B surface antigen clearance or seroconversion.

CONCLUSION

In children with chronic HBV infection, antivirals compared to no antiviral therapy improve HBV DNA suppression and frequency of alanine aminotransferase normalization and HBeAg seroconversion.