Loss of HBsAg antigen during treatment with entecavir or lamivudine in nucleoside-naïve HBeAg-positive patients with chronic hepatitis B

Development of Therapy Based on the Exploration of Biological Events Underlying the Pathogenetic Mechanisms of Chronic Hepatitis B Infection

According to the World Health Organization (WHO), an estimated 296 million people are chronically infected with hepatitis B virus (HBV). Approximately 15-25% of these people develop complications such as advanced chronic liver diseases (ACLDs). Mortality due to HBV-related complications accounted for an estimated 882,000 deaths in 2019. Potent preventive vaccines have already restricted new HBV infections, and several drugs are available to treat chronic HBV infections. However, the positive impacts of these drugs have been recorded in only a few patients with chronic HBV infection. These drugs do not show long-term efficacy and cannot halt the progression to complications. Thus, more effective and evidence-based therapeutic strategies need to be urgently developed for patients with chronic HBV infection. CHB is a pathological entity induced by HBV that progresses due to impaired host immunity. This indicates the inherent limitations of antiviral-drug-based monotherapy for treating patients with chronic HBV infection. Additionally, commercially available antiviral drugs are not available to patients in developing and resource-constrained countries, posing a challenge to achieving the following WHO goal: "Elimination of Hepatitis by 2030". As such, this review aimed to provide insights regarding evidence-based and effective management strategies for chronic HBV infection.

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.

Understanding Hepatitis B Virus Dynamics and the Antiviral Effect of Interferon Alpha Treatment in Humanized Chimeric Mice

Whereas the mode of action of lamivudine (LAM) against hepatitis B virus (HBV) is well established, the inhibition mechanism(s) of interferon alpha (IFN-α) is less completely defined. To advance our understanding, we mathematically modeled HBV kinetics during 14-day pegylated IFN-α-2a (pegIFN), LAM, or pegIFN-plus-LAM (pegIFN+LAM) treatment of 39 chronically HBV-infected humanized uPA/SCID chimeric mice. Serum HBV DNA and intracellular HBV DNA were measured frequently. We developed a multicompartmental mathematical model and simultaneously fit it to the serum and intracellular HBV DNA data. Unexpectedly, even in the absence of an adaptive immune response, a biphasic decline in serum HBV DNA and intracellular HBV DNA was observed in response to all treatments. Kinetic analysis and modeling indicate that the first phase represents inhibition of intracellular HBV DNA synthesis and secretion, which was similar under all treatments with an overall mean efficacy of 98%. In contrast, there were distinct differences in HBV decline during the second phase, which was accounted for in the model by a time-dependent inhibition of intracellular HBV DNA synthesis, with the steepest decline observed during pegIFN+LAM treatment (1.28/day) and the slowest (0.1/day) during pegIFN monotherapy. Reminiscent of observations in patients treated with pegIFN and/or LAM, a biphasic HBV decline was observed in treated humanized mice in the absence of an adaptive immune response. Interestingly, combination treatment did not increase the initial inhibition of HBV production but rather enhanced second-phase decline, providing insight into the dynamics of HBV treatment response and the mode of action of IFN-α against HBV. IMPORTANCE Chronic hepatitis B virus (HBV) infection remains a global health care problem, as we lack sufficient curative treatment options. Elucidating the dynamics of HBV infection and treatment response at the molecular level could facilitate the development of novel, more effective HBV antivirals. Currently, the only well-established small animal HBV infection model available is the chimeric uPA/SCID mice with humanized livers; however, the HBV inhibition kinetics under pegylated IFN-α-2a (pegIFN) in this model system have not been determined in sufficient detail. In this study, viral kinetics in 39 humanized mice treated with pegIFN and/or lamivudine were monitored and analyzed using a mathematical modeling approach. We found that the main mode of action of IFN-α is blocking HBV DNA synthesis and that the majority of synthesized HBV DNA is secreted. Our study provides novel insights into HBV DNA dynamics within infected human hepatocytes.

Functional cure for chronic hepatitis B: accessibility, durability, and prognosis

Hepatitis B surface antigen (HBsAg) clearance is regarded as the ideal endpoint for antiviral treatment in terms of drug withdrawal safety and improvements in prognosis. However, the overall rate of HBsAg clearance is low and differs based on treatment method and course. The recent application of combined and extended treatment strategies have improved the HBsAg clearance rate, and several patients achieved HBsAg clearance in clinical treatment. In addition, the durability of and clinical outcomes after HBsAg clearance have become the focus of both researchers and clinicians. This article reviews HBsAg clearance in terms of accessibility, durability, improvements in prognosis and relevant advances.

Comparison of Long-Term Clinical Outcomes Between Spontaneous and Therapy-Induced HBsAg Seroclearance

BACKGROUND AND AIMS

HBsAg seroclearance is considered a realistic goal in patients with chronic hepatitis B (CHB), known as "functional cure." However, it remains elusive whether nucleos(t)ide analogue (NUC)-induced HBsAg seroclearance, compared with spontaneous HBsAg seroclearance, differs in its association with favorable long-term clinical outcomes.

APPROACH AND RESULTS

A total of 1,972 CHB patients with confirmed HBsAg seroclearance at least two consecutive times, 6 months apart, were retrospectively analyzed. Risks of HCC development and composite clinical events, including HCC, liver-related death, and liver transplantation, were compared between spontaneous and NUC-induced HBsAg seroclearance. Of 1,972 patients, mean patient age was 53.7 years, and 64.4% were men. Cirrhosis was present in 297 (15.1%) patients. HBsAg seroclearance was achieved spontaneously in 1,624 (82.4%) patients and by NUC treatment in 348 (17.6%). HCC developed in 49 patients, with an annual incidence of 0.38 of 100 person-years (PY) during a median follow-up of 5.6 years. With 336 propensity-score-matched pairs, risks of HCC (P = 0.52) and clinical events (P = 0.14) were not significantly different between NUC-induced and spontaneous HBsAg seroclearance. By multivariable analysis, NUC-induced HBsAg seroclearance, compared with spontaneous HBsAg seroclearance, was not associated with the significantly higher risk of HCC (adjusted HR [AHR], 1.49; P = 0.26) and clinical events (AHR, 1.78; P = 0.06).

CONCLUSIONS

Risks of HCC and clinical events were not significantly different between spontaneous and NUC-induced HBsAg seroclearance. Nonetheless, annual risk of HCC exceeds the recommended cutoff for HCC surveillance even after HBsAg seroclearance, suggesting that continued HCC surveillance is required.

Incidences and Determinants of Functional Cure during Entecavir or Tenofovir Disoproxil Fumarate for Chronic Hepatitis B

BACKGROUND

Long-term incidences and baseline determinants of functional cure (HBsAg seroclearance) during entecavir (ETV) or tenofovir disoproxil fumarate (TDF) treatment are incompletely understood.

METHODS

This is an international multicenter cohort study of treatment-naïve chronic hepatitis B (CHB) patients who initiated on ETV or TDF without baseline malignancy. Patients were observed for HBsAg seroclearance until death or loss to follow-up. We calculated the incidences and explored the baseline determinants of HBsAg seroclearance using competing risk regression.

RESULTS

The analysis included 4,769 patients (median age, 50 years; 69.05% male), with a median follow-up of 5.16 years (26,614.47 person-years). HBsAg clearance occurred in 58 patients, yielding a 10-year cumulative incidence of 2.11% (95% CI, 1.54 -- 2.88%) and an annual rate of 0.22% (95% CI, 0.17--0.28%). Baseline predictors included low-level viremia with HBV DNA <2,000 IU/mL (adjusted sub-distribution HR [aSHR], 3.14; 95% CI, 1.80--5.49), elevated serum alanine aminotransferase (ALT) >200 U/L (aSHR, 3.68; 95% CI, 2.07--6.53), serum bilirubin (aSHR, 1.11 per mg/dL; 95% CI, 1.06--1.17), and fatty liver (aSHR, 1.84; 95% CI, 1.03--3.29).

CONCLUSION

HBsAg seroclearance rarely occurs in CHB patients treated with ETV or TDF and is associated with low-level viremia, ALT flare, bilirubin level, and fatty liver.

Pleural Effusion Related to Chronic Hepatitis B Virus Reactivation: A Rare Association

Despite worldwide vaccination campaigns, hepatitis B virus (HBV) infection remains a major public health problem. The natural history ranges from asymptomatic infection to severe liver injury or failure, chronic complications or reactivation episodes. The effects of HBV on the organism are immunomediated, possibly triggering extrahepatic manifestations. Since 1971, only a few cases of pleural effusion related to HBV infection have been described. We report HBV-associated pleural effusion occurring during a viral reactivation episode. Antiviral treatment directed towards pleural effusion related to HBV infection should be dictated by underlying liver disease severity and not pleural effusion severity.

LEARNING POINTS

In the presence of pleural effusion of unknown origin, especially if with simultaneous acute hepatitis, a viral aetiology should be suspected and pursued.The severity of liver disease and not the pleural effusion should guide antiviral treatment.

Sequential therapy from entecavir to tenofovir alafenamide versus continuous entecavir monotherapy for patients with chronic hepatitis B

Background and Aim

Although tenofovir alafenamide (TAF), as well as entecavir (ETV), is widely used as first‐line treatment for patients with chronic hepatitis B, there are only a few studies comparing sequential therapy from ETV to TAF and continuous ETV monotherapy in patients with maintained virologic response to ETV.

Methods

In a retrospective multicenter study, we investigated the efficacy and safety of sequential therapy from ETV to TAF (ETV‐TAF group) and compared them with continuous ETV monotherapy (ETV group), using propensity score matching, in chronic hepatitis B patients.

Results

From 442 patients, we analyzed 142 patients from each group comprising 71 patients matched for several data, including age, HBV genotype, hepatitis B envelope antigen, cirrhosis, alanine aminotransferase, platelet count, prior ETV monotherapy period, and hepatitis B surface antigen (HBsAg) change during prior ETV monotherapy. In the ETV‐TAF group, HBsAg levels significantly decreased from baseline to 48 weeks after switching to TAF (−0.02 log IU/mL, P = 0.038). HBcrAg levels also significantly decreased after switching to TAF (−0.1 log IU/mL, P = 0.004). However, there were no significant differences in the reduction of HBsAg and HBcrAg levels between the ETV‐TAF and ETV groups. There was no significant difference in the change of estimated glomerular filtration rate levels from baseline to 48 weeks between the two groups.

Conclusions

The present study indicated that the efficacy, especially of the HBsAg‐reducing action, and safety of sequential therapy from ETV to TAF were similar to those of continuous ETV monotherapy among chronic hepatitis B patients with maintained virologic response to ETV.

Factors Associated with Hepatitis B Surface Antigen Kinetics and Responses in Pegylated Interferon Alpha-2a Monotherapy for Patients with Chronic Hepatitis B

Objective Pegylated-interferon monotherapy is the standard treatment for patients with chronic hepatitis B; however, the factors associated with its therapeutic effects remain unclear. Methods Patients with chronic hepatitis B were treated with pegylated interferon α-2a for 48 weeks. We evaluated the kinetics of hepatitis B surface antigen (HBsAg) during treatment and follow-up periods and the factors associated with an HBsAg response (defined as a change in HBsAg of ≥-1 log IU/mL from baseline). Results The study population comprised 50 patients. The median baseline levels of hepatitis B virus DNA and HBsAg were 5.00 and 3.40 log IU/mL. The median values of HBsAg reduction from baseline were -0.44 (n=48), -0.41 (n=40), and -0.68 (n=11) log IU/mL at the end of treatment and at 48 and 144 weeks post-treatment, respectively. The rates of HBsAg response were 24.0% and 22.5% at the end of treatment and at 48 weeks post-treatment, respectively. A multivariate analysis identified HBsAg <3.00 log IU/mL as an independent baseline factor contributing to the HBsAg response at the end of treatment and 48 weeks post-treatment (p=1.07×10^-2 and 4.42×10^-2, respectively). There were significant differences in the reduction of the HBsAg levels at 12 weeks of treatment and in the incidence of serum ALT increase during treatment between patients with and without an HBsAg response. Conclusion These findings suggest that the baseline HBsAg level, HBsAg kinetics at 12 weeks of treatment, and ALT increase during treatment are important factors contributing to the HBsAg response in pegylated interferon α-2a monotherapy for patients with chronic hepatitis B.

Hepatitis B surface antigen seroclearance: Immune mechanisms, clinical impact, importance for drug development

HBsAg seroclearance occurs rarely in the natural history of chronic hepatitis B (CHB) infection and is associated with improved clinical outcomes. Many factors are associated with HBsAg seroconversion, including immune and viral factors. However, the immune mechanisms associated with HBsAg seroclearance are still difficult to elucidate. HBsAg seroclearance is the ideal aim of HBV treatment. Unfortunately, this goal is rarely achieved with current treatments. Understanding the mechanisms of HBsAg loss appears to be important for the development of curative HBV treatments. While studies from animal models give insights into the potential immune mechanisms and interactions occurring between the immune system and HBsAg, they do not recapitulate all features of CHB in humans and are subject to variability due to their complexity. In this article, we review recent studies on these immune factors, focusing on their influence on CHB progression and HBsAg seroconversion. These data provide new insights for the development of therapeutic approaches to partially restore the anti-HBV immune response. Targeting HBsAg will ideally relieve the immunosuppressive effects on the immune system and help to restore anti-HBV immune responses.

Stem Cell-Derived Viral Antigen-Specific T Cells Suppress HBV Replication through Production of IFN-γ and TNF-⍺

The viral antigen (Ag)-specific CD8⁺ cytotoxic T lymphocytes (CTLs) derived from pluripotent stem cells (PSCs), i.e., PSC-CTLs, have the ability to suppress hepatitis B virus (HBV) infection. After adoptive transfer, PSC-CTLs can infiltrate into the liver to suppress HBV replication. Nevertheless, the mechanisms by which the viral Ag-specific PSC-CTLs provoke the antiviral response remain to be fully elucidated. In this study, we generated the functional HBV surface Ag-specific CTLs from the induced PSC (iPSCs), i.e., iPSC-CTLs, and investigated the underlying mechanisms of the CTL-mediated antiviral replication in a murine model. We show that adoptive transfer of HBV surface Ag-specific iPSC-CTLs greatly suppressed HBV replication and prevented HBV surface Ag expression. We further demonstrate that the adoptive transfer significantly increased T cell accumulation and production of antiviral cytokines. These results indicate that stem cell-derived viral Ag-specific CTLs can robustly accumulate in the liver and suppress HBV replication through producing antiviral cytokines.

Long-term observation on hepatitis B surface antigen seroclearance in therapy experienced HIV/HBV co-infected Chinese

The aim of this retrospective study was to observe hepatitis B surface antigen (HBsAg) seroclearance and explore predictors of HBsAg loss in HIV/HBV-co-infected patients receiving long-term lamivudine or both tenofovir and lamivudine containing therapies. Quantification of HBsAg, hepatitis B e antigen and HBV DNA before and after initiation of HBV-active antiretroviral therapy in a total of 268 HIV/HBV-co-infected patients started treatment between 2005 and 2017 were performed. Over a median of 65.63 months of follow-up, 10 (3.7%) were observed HBsAg loss and the quantification of HBsAg in 7 (2.6%) patients were less than 50 IU/mL. With the prolongation of antiretroviral therapy duration time, the rates of HBsAg seroclearance tended to increase gradually, rising from 1.8% (3/163) during 2-4 years treatment to 29.4% (10/34) after antiretroviral therapy for up to 10 years. Lower baseline qHBsAg and HBV DNA levels and strong 12-month declines in qHBsAg were significantly associated with HBsAg seroclearance. The event of HBsAg seroclearance is uncommon among Chinese individuals with HIV/HBV co-infection who have been treated with anti-HBV containing antiretroviral therapy, and lifelong therapy for HBV is needed for HIV/HBV co-infected patients. Baseline qHBsAg and HBV DNA levels and qHBsAg decline rate were predictors for HBsAg seroclearance.

Stem Cell-Derived Viral Ag-Specific T Lymphocytes Suppress HBV Replication in Mice

Hepatitis B virus (HBV) infection is a global health issue. With over 350 million people affected worldwide, HBV infection remains the leading cause of liver cancer. This is a major concern, especially in developing countries. Failure of the immune system to mount an effective response against HBV leads to chronic infection. Although HBV vaccine is present and novel antiviral medicines are being created, eradication of virus-reservoir cells remains a major health topic. Described here is a method for the generation of viral antigen (Ag) -specific CD8⁺ cytotoxic T lymphocytes (CTLs) derived from induced pluripotent stem cells (iPSCs) (i.e., iPSC-CTLs), which have the ability to suppress HBV replication. HBV replication is efficiently induced in mice through hydrodynamic injection of an HBV expression plasmid, pAAV/HBV1.2, into the liver. Then, HBV surface Ag-specific mouse iPSC-CTLs are adoptively transferred, which greatly suppresses HBV replication in the liver and blood as well as prevents HBV surface Ag expression in hepatocytes. This method demonstrates HBV replication in mice after hydrodynamic injection and that stem cell-derived viral Ag-specific CTLs can suppress HBV replication. This protocol provides a useful method for HBV immunotherapy.

Association of virological breakthrough and clinical outcomes in entecavir-treated HBeAg-positive chronic hepatitis B

Background & aims

To evaluate virological breakthrough (VBT) and the risk of hepatocellular carcinoma (HCC) in HBeAg-positive chronic hepatitis B (CHB) patients receiving entecavir (ETV) treatment.

Methods

A retrospective cohort study was conducted in a tertiary referral hospital and a total of 228 HBeAg-positive CHB patients treated with ETV for more than 48 weeks were enrolled. Clinical outcome measures included HBeAg seroclearance, maintained virological response and the development of HCC.

Results

During a median follow-up period of 197 weeks, VBT developed in 26 (11.4%) patients (VBT group), and the other 202 patients without VBT (non-VBT group). The overall cumulative rate of HBeAg seroclearance in the VBT group and non-VBT group were 23.1% and 23.8%, 27.1% and 37.9%, 27.1% and 55.1%, 27.1% and 74.1%, 27.1% and 76.7% from week 48 to 240, respectively(p = 0.013). The cumulative probability of maintained virological responses from week 48 to 240 were 7.69% and 21.78%, 7.69% in the VBT groups and 36.85%, 7.69% and 51.68%, 7.69% and 64.97%, 7.69% and 72.1% in the non-VBT groups, respectively (p<0.001). In the multivariate analysis, age (p<0.001) and virological response at week 24 (p = 0.005) were independently associated with VBT. Cox regression analysis showed that cirrhosis had carried the highest risk for HCC (HR = 4.99, CI = 1.14–21.81, p = 0.033). Subgroup survival analysis by Kaplan–Meier method showed that patients with VBT had higher incidence of developing HCC than without VBT in cirrhotic patients (50% (95%CI = 1–99%) vs 9% (95% CI = 1–9%); p = 0.048).

Conclusions

VBT was associated with adverse clinical outcomes, including a low probability of HBeAg seroclearance, failure to achieve maintained virological responses, and a risk of developing HCC. Patients, particularly with cirrhosis, who had experienced VBT during ETV treatment, more likely developed HCC.

Improvements in the management of chronic hepatitis B virus infection

The primary goals of managing chronic hepatitis B (CHB) are prevention of liver-related complications and reduction of mortality. Universal vaccination has dramatically reduced the incidence of new infection, but the management of existing CHB patients are still challenging. Areas covered: This review compares the similarities and differences among the latest published regional guidelines on the indications and choices of antiviral therapy. We have summarized advances in virological biomarkers and non-invasive tests for liver fibrosis in disease assessment. Benefits and remaining challenges of current standard of care by peginterferon and nucleos(t)ide analogs (NA) have been presented. Data on combination therapy of peginterferon and NA in seeking functional cure of the disease is also critically discussed. We have also described the improvement in the management of CHB at pregnancy and prophylaxis in patients on chemotherapy and immunosuppressants. Expert commentary: Controversies exist in the assessment of disease activity for selection patients for treatment as well as on the use of tenofovir alafenamide as a safe and cost-effective alternative to tenofovir disoproxil fumarate. Though combination therapy of peginterferon and NA has induced HBsAg seroclearance in a small proportion of patients, peginterferon is not preferred in the future trend of drug development.

Clinical and virological outcomes of entecavir therapy in patients with chronic hepatitis B: A real life experience

BACKGROUND

Entecavir (ETV) is a nucleoside analogue (NA) that is effective for treatment of chronic hepatitis B (CHB) due to its low resistance rates and potent antiviral effects. We aimed to evaluate the clinical, biochemical and virological response to ETV in patients without a prior use of nucleos(t)ide (NA-naïve) vs. those who failed prior NA use (NA-experienced) in the treatment of CHB.

METHODS

Patients treated between April 2012 and December 2017 were retrospectively studied. A comparison was made between patients treated with ETV in NA-naïve Vs. NA-experienced. Complete virological response (CVR) was defined as achieving undetectable HBV-DNA level, up to 15 IU/ml, partial virological response (PVR) as 15-200 IU/ml and >200 IU/ml for no virological response (NVR) after one year of therapy.

RESULTS

Overall, 148 patients were included (69 NA-naïve and 79 NA-experienced). In NA-naïve group, 51%, 17% and 32% achieved CVR, PVR and NVR vs. 17%, 9% and 75% in NA-experienced group, respectively (p < 0.001). HBsAg seroconversion was achieved in 5.8% in NA-naïve group vs. 6.3% in NA-experienced group (p = 1.00). HBeAg seroconversion was 17% in NA-naïve group and 25% in NA-experienced group (p = 0.24). There was no significant difference in alanine transaminase normalization or in mortality rate between both groups; p = 0.87 and p = 1.00 respectively.

CONCLUSION

ETV therapy in CHB results in a better virological response in NA-naïve patients compared to NA-experienced. There were no differences between both groups in regards to the rate of HBsAg or HBeAg seroconversions, biochemical improvements or mortality.

Inhibition of HBV Expression in HBV Transgenic Mice Using AAV-Delivered CRISPR-SaCas9

The chronic production of hepatitis B viral (HBV) antigens could cause inflammation and necrosis, leading to elevation of liver enzymes from necrotic hepatocytes, hepatitis, cirrhosis, hepatocellular carcinoma, and liver failure. However, no current treatment is capable of significantly reducing HBsAg expression in patients. Our previous studies had confirmed the ability of CRISPR-Cas9 in disrupting HBV cccDNA. Here, to inhibit HBV expression efficiently in the mouse model of chronic HBV infection, the miniaturized CRISPR-SaCas9 system compatible with a HBV core region derived guide-RNA had been packaged in recombinant adeno-associated virus (AAV) type 8, which lowered the levels of serum HBsAg, HBeAg, and HBV DNA efficiently in HBV transgenic mice during 58 days continuous observation after vein injection. It further confirms the potential of the CRISPR-Cas9 technique for use in hepatitis B gene therapy.

Analysis of hepatitis B surface antigen (HBsAg) using high-sensitivity HBsAg assays in hepatitis B virus carriers in whom HBsAg seroclearance was confirmed by conventional assays

AIM

We investigated the utility of high-sensitivity hepatitis B surface antigen (HBsAg) assays compared with conventional HBsAg assays.

METHODS

Using serum samples from 114 hepatitis B virus (HBV) carriers in whom HBsAg seroclearance was confirmed by conventional HBsAg assays (cut-off value, 0.05 IU/mL), the amount of HBsAg was re-examined by high-sensitivity HBsAg assays (cut-off value, 0.005 IU/mL). Cases negative for HBsAg in both assays were defined as consistent cases, and cases positive for HBsAg in the high-sensitivity HBsAg assay only were defined as discrepant cases.

RESULTS

There were 55 (48.2%) discrepant cases, and the range of HBsAg titers determined by high-sensitivity HBsAg assays was 0.005-0.056 IU/mL. Multivariate analysis showed that the presence of nucleos(t)ide analog therapy, liver cirrhosis, and negative anti-HBs contributed to the discrepancies between the two assays. Cumulative anti-HBs positivity rates among discrepant cases were 12.7%, 17.2%, 38.8%, and 43.9% at baseline, 1 year, 3 years, and 5 years, respectively, whereas the corresponding rates among consistent cases were 50.8%, 56.0%, 61.7%, and 68.0%, respectively. Hepatitis B virus DNA negativity rates were 56.4% and 81.4% at baseline, 51.3% and 83.3% at 1 year, and 36.8% and 95.7% at 3 years, among discrepant and consistent cases, respectively. Hepatitis B surface antigen reversion was observed only in discrepant cases.

CONCLUSIONS

Re-examination by high-sensitivity HBsAg assays revealed that HBsAg was positive in approximately 50% of cases. Cumulative anti-HBs seroconversion rates and HBV-DNA seroclearance rates were lower in these cases, suggesting a population at risk for HBsAg reversion.

Advances with using CRISPR/Cas-mediated gene editing to treat infections with hepatitis B virus and hepatitis C virus

Chronic infections with hepatitis B and hepatitis C viruses (HBV and HCV) account for the majority of cases of cirrhosis and hepatocellular carcinoma. Current therapies for the infections have limitations and improved efficacy is necessary to prevent complications in carriers of the viruses. In the case of HBV persistence, the replication intermediate comprising covalently closed circular DNA (cccDNA) is particularly problematic. Licensed therapies have little effect on cccDNA and HBV replication relapses following treatment withdrawal. Disabling cccDNA is thus key to curing HBV infections and application of gene editing technology, such as harnessing the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9 (Cas9) system, has curative potential. Several studies have reported good efficacy when employing CRISPR/Cas technologies to disable HBV replication in cultured cells and in hydrodynamically injected mice. Recent advances with HCV drug development have revolutionized treatment of the infection. Nevertheless, individuals may be refractory to treatment. Targeting RNA from HCV with CRISPR/Cas isolated from Francisella novicida may have therapeutic utility. Although preclinical work shows that CRISPR/Cas technology has potential to overcome infection with HBV and HCV, significant challenges need to be met. Ensuring specificity for viral targets and efficient delivery of the gene editing sequences to virus-infected cells are particularly important. The field is at an interesting stage and the future of curative antiviral drug regimens, particularly for treatment of chronic HBV infection, may well entail use of combinations that include derivatives of CRISPR/Cas.

Host genetic factors in predicting response status in chronic hepatitis B patients discontinuing nucleos(t)ide analogs

BACKGROUND/AIMS

The optimal duration of nucleos(t)ide analogs (NAs) therapy in chronic hepatitis B (CHB) patients remains unsatisfactory. Previous studies have confirmed the important role of host genetic factors in determining the outcome of HBV infection. This study tries to determine the role of host genetic factors in predicting response status in CHB patients discontinuing NAs according to stringent cessation criteria.

PATIENTS AND METHODS

Participating patients came from a prospective NAs- discontinuation cohort since June 1999. Six single-nucleotide polymorphisms (SNPs) were selected according to previous report. SNaPshot assay was used for DNA SNPs analyses.

RESULTS

Seventy-six CHB patients were enrolled in our study, of which 61 patients were HBeAg-positive and 15 patients were HBeAg-negative. rs1883832 in the Kozak sequence of CD40 displayed an AUROC of 0.778 in predicting response status in CHB patients with HBeAg seroconversion and a genotype of CT was associated with sustained response in this subpopulation. The diagnostic performance of combinative index (rs1883832, age, and HBsAg at discontinuation) seemed to be better than that of rs1883832, but no statistical difference was observed. rs1883832 was also evaluated as an independent factor for response status by multivariate logistic regression. For HBeAg-negative CHB patients, rs9277535 at HLA-DP presents a Spearman correlation coefficient of 0.582 (P = 0.023) with virological relapse after discontinuation of NAs.

CONCLUSIONS

rs1883832 serves as a valuable predictive factor for CHB patients with HBeAg seroconversion. rs9277535 at HLA-DP might also be a valuable predictive factor for CHB patients with HBeAg-negative, however, further verifications are recommended due to study limitations.

Research priorities for the discovery of a cure for chronic hepatitis B: Report of a workshop

In early 2017, the Hepatitis B Foundation invited 30 experts in the fields of hepatitis B and liver cancer research to identify projects they deemed important to the goal of finding a cure for chronic hepatitis B and D and the diseases with which these viral infections are associated. They were also asked to identify general categories of research and to prioritize sub-project topics within those areas. The experts generally agreed on broadly defined areas of research, but there was usually little difference between the highest and lowest scoring projects; for the most part, all programs described in this document were considered valuable and necessary. An executive summary of this discussion was recently published (Alter et al., Hepatology 2017). The present manuscript reports the areas of research identified by the workshop participants, provides a brief rationale for their selection, and attempts to express differences among the priorities assigned to each area of research, when such distinctions were expressed.

Hepatitis B surface antigen loss and sustained viral suppression in Asian chronic hepatitis B patients: A community-based real-world study

Community-based real-world outcomes on effectiveness of antiviral therapies for chronic hepatitis B virus (CHB) in Asians are limited. Whether hepatitis B surface antigen (HBsAg) loss correlates with undetectable virus and alanine aminotransferase (ALT) normalization on treatment or what predicts risk of seroreversion or detectable virus after stopping therapy is unclear. We aim to evaluate rates and predictors of HBsAg loss, seroconversion, ALT normalization and undetectable HBV DNA, including HBsAg seroreversion or re-emergence of HBV DNA among Asian CHB patients. We retrospectively evaluated 1072 CHB adults on antiviral therapy at two community gastroenterology clinics from 1997 to 2015. Rates of HBsAg loss, ALT normalization, achieving undetectable HBV DNA and developing surface antibody (anti-HBs) were stratified by HBeAg status. Following HBsAg loss, HBsAg seroreversion or re-emergence of detectable HBV DNA was analysed. With median treatment of 76.7 months, the overall rate of HBsAg loss was 4.58%, with similar HBsAg loss rates between HBeAg-positive and HBeAg-negative patients (4.44% vs 4.71%, P=.85) in a predominantly Asian population (98.1%). Among HBsAg loss patients, 33.3% developed anti-HBs, 95.8% achieved undetectable virus and 66.0% normalized ALT. No significant baseline or on-treatment predictors of HBsAg loss were observed. While six patients who achieved HBsAg loss had seroreversion with re-emergence of HBsAg positivity, viral load remained undetectable, demonstrating the sustainability of viral suppression. Among a large community-based real-world cohort of Asian CHB patients treated with antiviral therapy, rate of HBsAg loss was 4.58%. Despite only 33.3% of HBsAg loss patients achieving anti-HBs, nearly all patients achieved sustained undetectable virus.

Clinical response to long-term tenofovir monotherapy in Korean chronic hepatitis B patients

BACKGROUND

Tenofovir disoproxil fumarate (TDF) is a potent nucleotide analogue recommended as first-line monotherapy for chronic hepatitis B (CHB). We investigated the clinical response to TDF monotherapy in Korean CHB patients.

METHODS

A total of 90 CHB patients [55 hepatitis B e antigen (HBeAg)-positive and 35 HBeAg-negative] who received TDF monotherapy for >2year, were enrolled. Quantitative hepatitis B surface antigen (qHBsAg) levels, serum alanine aminotransferase (ALT), HBeAg, anti-HBe and HBV DNA levels were measured during treatment. Virologic response (VR) was defined as undetectable HBV DNA level.

RESULTS

The cumulative incidences of complete virologic response (CVR) were 75.6% and 89.9% at months 12 and 24, respectively. The cumulative CVR rates were significantly higher in HBeAg-negative than HBeAg-positive group (P<0.001). HBeAg loss/seroconversion was observed in 21 (38.2%) out of 55 HBeAg-positive patients. One HBeAg-positive and 1 HBeAg-negative patients (2.2%) achieved HBsAg loss at months 6 and 8 of TDF therapy, respectively. Baseline HBV DNA level and qHBsAg were significant predictive factors for a CVR (P=0.001 and P<0.001, respectively).

CONCLUSIONS

Virologic, serologic, biochemical responses were achieved in both HBeAg-positive and HBeAg-negative patients under 24-month TDF therapy. Monitoring using baseline HBV DNA and qHBsAg levels would be helpful to predict CVR.

Antibody-mediated immunotherapy against chronic hepatitis B virus infection

The currently available drugs to treat hepatitis B virus (HBV) infection include interferons and nucleos(t)ide analogs, which can only induce disease remission and are inefficient for the functional cure of patients with chronic HBV infection (CHB). Since high titers of circulating hepatitis B surface antigen (HBsAg) may be essential to exhaust the host anti-HBV immune response and they cannot be significantly reduced by current drugs, new antiviral strategies aiming to suppress serum hepatitis B surface antigen (HBsAg) could help restore virus-specific immune responses and promote the eradication of the virus. As an alternative strategy, immunotherapy with HBsAg-specific antibodies has shown some direct HBsAg suppression effects in several preclinical and clinical trial studies. However, most described previously HBsAg-specific antibodies only had very short-term HBsAg suppression effects in CHB patients and animal models mimicking persistent HBV infection. More-potent antibodies with long-lasting HBsAg clearance effects are required for the development of the clinical application of antibody-mediated immunotherapy for CHB treatment. Our recent study described a novel mAb E6F6 that targets a unique epitope on HBsAg. It could durably suppress the levels of HBsAg and HBV DNA via Fcγ receptor-dependent phagocytosis in vivo. In this commentary, we summarize the current research progress, including the therapeutic roles and mechanisms of antibody-mediated HBV clearance as well as the epitope-determined therapeutic potency of the antibody. These insights may provide some clues and guidance to facilitate the development of therapeutic antibodies against persistent viral infection.

HBsAg seroclearance or seroconversion induced by peg-interferon alpha and lamivudine or adefovir combination therapy in chronic hepatitis B treatment: a meta-analysis and systematic review

BACKGROUND AND AIMS

Seroclearance or seroconversion of hepatitis B surface antigen (HBsAg) is generally considered as the clinical endpoint. The purpose of the present meta-analysis was to evaluate pegylated interferon alpha (PEG-IFNα) with or without lamivudine (LAM) or adefovir (ADV) combination treatment in HBsAg seroclearance or seroconversion with CHB.

METHODS

Randomized controlled trials of adults with CHB prior to May 30th 2015, with 48-52 weeks of PEG-IFNα and LAM or ADV combination therapy or monotherapy, were included. Review Manager Software 5.2.0 was used for meta-analysis.

RESULTS

No statistical difference was noticed in HBsAg seroclearance (9.9% vs 7.1%, OR = 1.47, 95% CI 0.75, 2.90; p = 0.26) or observed in HBsAg seroconversion (4.2% vs 3.7%, OR = 1.17, 95% CI 0.57, 2.37; p = 0.67) between PEG-IFNα + LAM and PEG-IFNα + placebo for 24-26 weeks follow-up after treatment on hepatitis B e antigen (HBeAg)-positive CHB. Statistical difference was not showed in HBsAg disappearance (10.5% vs 6.4%, OR = 1.68, 95% CI 0.75, 3.76; p = 0.21) but was demonstrated in HBsAg seroconversion (6.3% vs 0%, OR = 7.22, 95% CI 1.23, 42.40; p = 0.03) between PEG-IFNα + ADV and PEG-IFNα for 48-52 weeks treatment on HBeAg-positive CHB By systematical evaluation, there were no differences in HBsAg disappearance and seroconversion between PEG-IFNα + placebo and PEG-IFNα + LAM for 48-52 weeks treatment on HBeAg-positive CHB. There were no differences in HBsAg disappearance and seroconversion between PEG-IFNα + placebo and PEG-IFNα + LAM during 24 weeks to 3 years follow-up after treatment on HBeAg-negative CHB by systematical evaluation.

CONCLUSION

The combination between PEG-IFNα and LAM or ADV was not superior to monotherapy of PEG-IFNα in terms of HBsAg seroclearance or seroconversion.

Antiviral effects of anti-HBs immunoglobulin and vaccine on HBs antigen seroclearance for chronic hepatitis B infection

BACKGROUND AND AIMS

Interferon and nucleotide/nucleoside analogues are the main treatments for chronic hepatitis B. These drugs effectively reduce serum hepatitis B virus (HBV) DNA titers but fail to sufficiently reduce hepatitis B surface antigen (HBsAg) levels. Following the recent identification of sodium taurocholate cotransporting polypeptide as a receptor for HBV entry, inhibition of HBV entry has become an attractive therapeutic target for chronic hepatitis B treatment. We therefore evaluated the antiviral effects of antibody to HBsAg (anti-HBs) immunoglobulin (HBIG), which can inhibit HBV entry, by in an vivo study and a clinical trial.

METHODS

In the in vivo study, HBV-infected mice were generated from human hepatocyte chimeric mice and treated with HBIG. A clinical trial evaluating HBIG therapy in patients was also performed.

RESULTS

In the mouse study, HBV DNA titers were reduced and serum HBsAg titers decreased to undetectable levels following high-dose HBIG injection. On the basis of this result, eight chronic hepatitis B patients, who had received long-term nucleotide analogue treatment, were treated with monthly HBIG injections as an additional treatment. After 1 year of treatment, an HBsAg level reduction of more than 1 log IU/mL was observed in four patients, and three patients became anti-HBs positive. No adverse events occurred during HBIG therapy.

CONCLUSION

These results suggest that monthly HBIG injection might benefit patients with chronic hepatitis B whose HBsAg titer becomes lower following long-term nucleotide/nucleoside analogue treatment.

Spontaneous resolution of de novo hepatitis B after living donor liver transplantation with hepatitis B core antibody positive graft: a case report

Background

Hepatitis B core antibody (HBcAb)-positive graft is reported to cause de novo hepatitis B after liver transplantation with a probability of 38–100 % without prophylaxis. Hepatitis B surface antigen loss is reported to be achieved with a probability of only 3–8 % in the patients treated by antiviral agents. We present an extremely rare case of spontaneous resolution of de novo hepatitis B after living donor liver transplantation (LDLT) with HBcAb-positive graft.

Case presentation

An 8-year-old female patient underwent LDLT for end-stage biliary atresia using an HBcAb-positive left lobe graft. After transplantation, she did not receive any prophylactic agents for hepatitis B. Two years after LDLT, she was diagnosed with chronic hepatitis B. Six years after LDLT, liver fibrosis and hepatitis activity were advanced and lamivudine was started. Two years after lamivudine administration, emergence of a lamivudine-resistant YMDD mutant was detected and adefovir dipivoxil was combined with lamivudine. Hepatitis B virus deoxyribonucleic acid (HBV-DNA) became undetectable soon after the addition of adefovir dipivoxil. Twelve years after transplantation, acute rejection occurred and steroid pulse therapy was performed, but hepatitis B did not become severe and HBV-DNA continued to be undetectable. Fifteen years after LDLT, she voluntarily discontinued medication of all drugs, including immunosuppressive agents and antiviral drugs for 1 year because of mental instability. After an interval of 1 year, liver function was normal and her serological HBV status was as follows: HBsAg(−), HBsAb(+), HBeAb(−), HBeAb(+), HBcAb(+) and HBV-DNA(−). From these results, we diagnosed her condition as spontaneous clearance of de novo hepatitis B. The patient is free of antiviral therapies and continues to take a low dose of immunosuppressive drugs and is leading a normal life.

Conclusions

In this case, HBsAg loss is finally achieved but we need to follow carefully for HBV reactivation with the fibrosis of the graft in mind.

Treatment strategies according to genotype for chronic hepatitis B in children

This review article was requested by editor-in-chief of this journal as 'pediatric CHB treatment' for the upcoming special issue. The main objective of chronic hepatitis B (CHB) treatment is diminishing the risk of complications related to chronic liver disease. In Asia, there are already some reports about hepatocellular carcinoma (HCC) in hepatitis B virus (HBV) infected children. The key points of treatment in children with CHB infections are selection of which patients to treat and conformation of the optimal therapy time that would reduce viral resistance. The choice of therapy is determined by the district (Western/Eastern), HBV genotype, medical accessibility, and economic state of the country. Newly developed nucleos(t)ide analogues (NAs) are potent in children with CHB. However, to improve therapeutic efficacy, physicians are recommended to follow treatment guidelines and determine the specific genotype in the CHB patient. In this article, the treatment of pediatric CHB is reviewed according to differences in genotype.

An Effective Molecular Target Site in Hepatitis B Virus S Gene for Cas9 Cleavage and Mutational Inactivation

Chronic hepatitis B infection remains incurable because HBV cccDNA can persist indefinitely in patients recovering from acute HBV infection. Given the incidence of HBV infection and the shortcomings of current therapeutic options, a novel antiviral strategy is urgently needed. To inactivate HBV replication and destroy the HBV genome, we employed genome editing tool CRISPR/Cas9. Specifically, we found a CRISPR/Cas9 system (gRNA-S4) that effectively targeted the HBsAg region and could suppress efficiently viral replication with minimal off-target effects and impact on cell viability. The mutation mediated by CRISPR/Cas9 in HBV DNA both in a stable HBV-producing cell line and in HBV transgenic mice had been confirmed and evaluated using deep sequencing. In addition, we demonstrated the reduction of HBV replication was caused by the mutation of S4 site through three S4 region-mutated monoclonal cells. Besides, the gRNA-S4 system could also reduce serum surface-antigen levels by 99.91 ± 0.05% and lowered serum HBV DNA level below the negative threshold in the HBV hydrodynamics mouse model. Together, these findings indicate that the S4 region may be an ideal target for the development of innovative therapies against HBV infection using CRISPR/Cas9.

Chronic Hepatitis B Virus Infection: Disease Revisit and Management Recommendations

Chronic hepatitis B virus (HBV) infection evolves from immune-tolerance phase, through immune clearance phase to a quiescent phase or reactivation as hepatitis B e antigen-negative hepatitis. Persistent infection may result in the development of cirrhosis and hepatocellular carcinoma (HCC). Host factors including gender, age, family history, HLA-DP, and viral factors including HBV DNA, genotypes, precore mutations, pre-S deletions, and hepatitis B surface antigen (HBsAg) level are associated with the development of these complications. Risk scores for the development of HCC have been derived. Patients with persistently elevated alanine aminotransferase levels (>30 for males; >19 U/L for females) and HBV DNA levels >2000 IU/mL should be treated. Patients with established cirrhosis with detectable HBV DNA should also be treated. The recommended first-line agents include pegylated interferon and 2 nucleos(t)ide analogs, entecavir and tenofovir. NAs require long-term treatment to maintain suppression of HBV DNA. They have been shown to decrease hepatic fibrosis, or reverse cirrhosis and to reduce the development of HCC. They have very low rates (0% to 1.2%) of resistance. HBsAg seroclearance, although the ideal endpoint, is only achievable in 10% to 12% of patients by multicenter trials usually studying relatively young patients. Patients on long-term treatment should be monitored for viral breakthrough that may be due to noncompliance or the development of resistance. Newer agents are under trials to enhance the rate of HBsAg seroclearance. However, even with the current NAs, long-term treatment of >6 years can markedly reduce the covalently closed circular DNA, the viral component responsible for initiation of viral replication.

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

BACKGROUND

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

PATIENTS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

A comparison of lamivudine vs entecavir for prophylaxis of hepatitis B virus reactivation in allogeneic hematopoietic stem cell transplantation recipients: a single-institutional experience

The aim of this study was to compare the efficacy of lamivudine vs entecavir in the prevention of hepatitis B virus (HBV) reactivation in HBV surface Ag (HBsAg)-positive patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). A total of 216 consecutive patients were enrolled and retrospectively reviewed. Of these patients, 119 received lamivudine and 97 received entecavir. The median treatment duration to complete virological response in patients with baseline HBV-DNA levels >10(5) copies/mL was 2.0 months in the entecavir group, significantly shorter than that of the lamivudine group. After a median follow-up of 24 months post transplantation, the cumulative incidence rates of HBV reactivation at 6, 12 and 24 months following transplantation were 3.0%, 7.0% and 24.0% in the lamivudine group, and 0%, 0% and 2.0% in the entecavir group, respectively. In addition, entecavir treatment was associated with lower cumulative incidence rates of severe hepatitis caused by HBV reactivation. Mutations leading to drug resistance were detected in 25 patients in the lamivudine group and in only one patient in the entecavir group. Our data indicate that compared with lamivudine, entecavir has more potent antiviral efficacy and may be a better choice for prophylaxis of HBV reactivation in HBsAg-positive allo-HSCT recipients.

Long-term effects of peginterferon alfa-2a therapy in Japanese patients with chronic hepatitis B virus infection

Background

There is no information on the long-term effects of peginterferon (PEG-IFN) alfa-2a therapy for chronic hepatitis B (CHB) in Japan. This double-blind, randomized trial investigated the efficacy of PEG-IFN therapy.

Methods

We analyzed 22 Japanese patients with CHB (hepatitis B e antigen [HBeAg]-positive: 17, HBeAg-negative: 5) treated with PEG-IFN alfa-2a and followed-up posttreatment for 5 years. Responders represented patients who showed persistent normalization of alanine transferase (ALT) levels, HBeAg clearance, and low hepatitis B virus (HBV) DNA levels (HBeAg-positive patient; <5 log copies/mL, HBeAg-negative patient; <4.3 log copies/mL) at end of treatment, and at 1, 2, 3, 4 and 5 years posttreatment. In addition, baseline HBeAg-positive patients who showed sustained normalization of ALT level, HBeAg clearance, and low HBV DNA level for more than 6 months until at 1, 2, 3, 4, and 5 years after completion of PEG-IFN were also classified as “triple responders” and the proportion of triple responders relative to all patients was termed the “triple response rate”.

Results

The response rates among HBeAg-positive patients were 13 %, 25 %, 14 %, 21 % and 21 % at end of treatment, and at 1, 2, 3, 4, and 5 years, respectively. The response rate tended to be higher in patients treated for 48 than 24 weeks. The respective response rates among HBeAg-negative patients were 0 %, 20 %, 20 %, 20 % and 25 %. During the treatment period, hepatitis B surface antigen (HBsAg) clearance at 3.5 years was noted in one patient, who was 37-year-old, male, had genotype C and received PEG-IFN alfa-2a at 90 μg for 48 weeks.

Conclusion

At 5 years after completion of PEG-IFN, the triple response rate in HBeAg-positive patients and combined response rate in HBeAg-negative patients were 21 % (3/14) and 25 % (1/4), respectively. The triple response was seen in three patients who had all been treated with PEG-IFN for 48 weeks.

Monotherapy for hepatitis B infection: a review of treatment options

Chronic hepatitis B (CHB) is a global health problem, causing liver failure, cirrhosis and hepatocellular carcinoma. CHB treatment aims to prevent liver-related complication. The treatment of CHB infection includes monotherapy with either interferons (IFNs) or nucleos(t)ide (NUC) analogs. IFNs have moderate antiviral effects, and their use is limited by side effects. With the availability of NUCs, IFN-intolerant and decompensated cirrhotic patients began to be treated. Lamivudine and telbivudine, nucleoside analogs, have low genetic barrier to resistance. Adefovir, a nucleotide analog, has moderate potency and potential nephrotoxicity. Entecavir and tenofovir, with their high potency, high genetic barrier to resistance and favorable safety profile are the standard of care in CHB treatment. Long-term use of NUCs with maintained viral suppression results in a decrease in liver-related complications.

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.

Long-Term Telbivudine Treatment Results in Resolution of Liver Inflammation and Fibrosis in Patients with Chronic Hepatitis B

Introduction

The long-term goal of chronic hepatitis B (CHB) treatment is improvement of liver disease and prevention of cirrhosis. The aim of this study was to assess whether prolonged telbivudine treatment improves liver inflammation and fibrosis. The primary objective was to evaluate the proportion of patients with absence/minimal inflammation (Knodell necroinflammatory score ≤3) on liver biopsy at Year 5.

Methods

Fifty-seven patients aged 16–70 years with a clinical history of CHB and active viral replication (38 hepatitis B e antigen [HBeAg] positive and 19 HBeAg negative) were followed for 6 years: 33 received telbivudine 600 mg/day continuously for 5 years; 24 received lamivudine 100 mg/day for 2 years and then telbivudine for 3 years. Liver biopsies were taken pre-treatment and after 5 years of treatment.

Results

At baseline, mean (standard deviation) serum hepatitis B virus (HBV) DNA load was 8.5 (1.7) log₁₀ copies/mL, Knodell necroinflammatory score was 7.6 (2.9), and Ishak fibrosis score was 2.2 (1.1). After antiviral treatment (median duration: 261 weeks), liver histology improved with increased proportions of patients with absence/minimal liver inflammation (Knodell necroinflammatory score ≤3), from 16% (9/57) at baseline to 98% (56/57), and absence/minimal fibrosis (Ishak score ≤1), from 25% (14/57) at baseline to 84% (48/57). At Year 5, HBV DNA load was <300 copies/mL for all patients; cumulative HBeAg loss and seroconversion rates were 88% and 77%, respectively. At Year 6, 95% of patients with abnormal baseline glomerular filtration rate (60–90 mL/min/1.73 m²) improved to normal GFR (>90 mL/min/1.73 m²).

Conclusion

Long-term telbivudine treatment with profound and durable viral suppression significantly improved liver histology, thus achieving the long-term goals of CHB treatment. FibroScan^® results after 5 and 6 years of treatment (in almost 20% of patients) were consistent with this information.

Funding

Novartis and National Science and Technology Major Project (2012ZX10002003).

Trial registration

ClinicalTrials.gov # NCT00877149.

Electronic supplementary material

The online version of this article (doi:10.1007/s12325-015-0232-2) contains supplementary material, which is available to authorized users.

Incidence of hepatocellular carcinoma after HBsAg seroclearance in chronic hepatitis B patients: a need for surveillance

BACKGROUND & AIMS

Little is known about whether surveillance for hepatocellular carcinoma (HCC) is worthwhile in chronic hepatitis B virus (HBV)-infected patients who have achieved HBsAg seroclearance.

METHODS

A retrospective analysis of 829 patients (mean age: 52.3 years; 575 males; 98 with cirrhosis) achieving HBsAg seroclearance was performed at a tertiary hospital in Korea between 1997 and 2012. We evaluated incidence rates of HCC, and validated CU-HCC score based on data at the time of HBsAg seroclearance.

RESULTS

During a follow-up of 3464 patient-years, 19 patients developed HCC (annual rate: 0.55%). Liver cirrhosis (hazard ratio [HR]: 10.80; 95% confidence interval [CI]: 4.25-27.43), male gender (HR: 8.96; 95% CI: 1.17-68.80), and age ⩾50 years at the time of HBsAg seroclearance (HR: 12.14; 95% CI: 1.61-91.68) were independently associated with HCC. The estimated annual incidence of HCC was 2.85% and 0.29% in patients with and without cirrhosis, respectively. Among the non-cirrhotic patients, the annual rate of HCC was higher in the male patients than in the females (0.40% vs. 0%, respectively), and all the HCCs developed after age 50. The time-dependent area under the receiver operating characteristic curves for the CU-HCC score for 5 year and 10 year HCC prediction were 0.85 and 0.74, respectively.

CONCLUSIONS

HCC surveillance should be considered for cirrhotic patients and non-cirrhotic male patients over age 50, even after HBsAg seroclearance, especially those infected with HBV genotype C. HBsAg seroclearance at age ⩾50years was also an independent predictor for HCC.

Hepatitis B virus genotypes and variants

At least 10 hepatitis B virus (HBV) genotypes (A to J) with distinct geographic distributions and several HBV mutants, including precore/core promoter mutations and pre-S/S deletion mutations, have been recognized to be not only predictive of liver disease progression but also associated with response to antiviral therapy. HBV genotype-specific pathogenesis may contribute to heterogeneous clinical outcomes in chronic hepatitis B patients across the world. For example, patients with HBV genotypes C and D infection have a lower rate of spontaneous HBeAg seroconversion. In addition, HBV genotypes C and D have a higher frequency of core promoter and pre-S mutations than genotypes A and B. Genotypes C and D also carry a higher lifetime risk of cirrhosis and HCC development than genotypes A and B. Core promoter and pre-S mutations also correlate with an increased risk of hepatocellular carcinoma (HCC). Therapeutically, genotypes A and B patients have a better response to interferon-based therapy than genotypes C and D patients, but the response to nucleos(t)ide analogs is comparable across different HBV genotypes. In conclusion, HBV genotypes and variants may serve as viral genetic markers to predict disease progression as well as help practicing physicians optimize individualized antiviral therapy in clinical practice.

Seroclearance of Hbsag in Chronic Hepatitis B Virus Patients on Lamivudine Therapy: A 10 Year Experience

Introduction:

The aim of this study was to determine hepatitis B surface antigen (HBsAg) seroclearance rate among patients treated with lamivudine at a specialized tertiary care referral hospital in Tehran, Iran.

Methods:

All patients on lamivudine (biovudin®) therapy at a dose of 100 mg/day, who showed seroclearnace between March 2001 and September 2011 were recruited. The main evaluation parameters were duration of HBsAg seroclearance and duration of HBsAg seroconversion. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were evaluated using standard methods. HBsAg seroclearance was defined as two consecutive negative serums HBsAg at least 6 months apart, whereas HBsAg seroconversion was defined as the disappearance of serum HBsAg and the presence of anti-HBs for >6 months.

Results:

A total of 203 chronic HBV patients treated with lamivudine at a dose of 100 mg/day were included in the study. HBsAg seroclearance and seroconversion were observed in 11 patients after the initiation of the lamivudine therapy. Overall, in lamivudine responder patients, the mean time to HBsAg seroclearance was 26.90±10.93 months (range: 12-48 months). Furthermore, the responders showed seroconversion after a mean time of 26.90±11.08 months from the initiation of lamivudine therapy. When comparing the characteristics of those who have responded to lamivudine and those who have not responded, baseline HBV-DNA levels was significantly lower in responder than non responder patients (p<0.001). Meantime, there was no difference in age, sex, baseline ALT, AST and liver biopsy score between lamivudine responder and lamivudine non-responder patients.

Conclusion:

Despite introduction of tenofovir and entecavir as first line treatment for chronic HBV infection, lamivudine remains to be a low cost, safe and effective drug for HBsAg seroclearnace.

Seven-year efficacy and safety of treatment with tenofovir disoproxil fumarate for chronic hepatitis B virus infection

BACKGROUND

Long-term tenofovir disoproxil fumarate (TDF) treatment for chronic hepatitis B (CHB) is associated with sustained viral suppression and regression of fibrosis and cirrhosis at year 5 (240 weeks) and no TDF resistance through 6 years (288 weeks).

AIM

We assessed the efficacy, safety, and resistance of TDF for up to 7 years (336 weeks) in HBeAg-positive and HBeAg-negative CHB patients.

METHODS

Patients who completed 1 year (48 weeks) of randomized treatment with TDF or adefovir dipivoxil were eligible to receive open-label TDF for a total duration of 8 years (384 weeks).

RESULTS

Of 641 patients initially randomized, 585 (91.3 %) entered the open-label phase; 437/585 (74.7 %) remained on study at year 7. For patients on treatment at year 7, 99.3 % maintained viral suppression (HBV DNA < 69 IU/mL), 80.0 % achieved serum alanine aminotransferase normalization, and in HBeAg-positive patients, 84/154 (54.5 %) and 25/154 (11.8 %) achieved HBeAg and HBsAg loss, respectively. One/375 (0.3 %) HBeAg-negative patients achieved HBsAg loss. No resistance to TDF was detected through 7 years. During the open-label phase, grade 3/4 drug-related adverse events were uncommon (1.0 %); ten (1.7 %) patients had elevation of serum creatinine ≥ 0.5 mg/dL above baseline. No significant change in bone mineral density was observed from year 4 to year 7 (week 192 to week 336).

CONCLUSIONS

Long-term TDF treatment was associated with sustained virologic, biochemical, and serologic responses, without resistance. TDF treatment was well tolerated, with a low incidence of renal and bone events. These data confirm the safety and efficacy of long-term TDF for CHB.

Targeted in vivo delivery of siRNA and an endosome-releasing agent to hepatocytes

The discoveries of RNA interference (RNAi) and short interfering RNAs (siRNAs) have provided the opportunity to treat diseases in a fundamentally new way: by co-opting a natural process to inhibit gene expression at the mRNA level. Given that siRNAs must interact with the cells' natural RNAi machinery in order to exert their silencing effect, one of the most fundamental requirements for their use is efficient delivery to the desired cell type and, specifically, into the cytoplasm of those cells. Numerous research efforts involving the testing of a large number of delivery approaches using various carrier molecules and inventing several distinct formulation technologies during the past decade illustrate the difficulty and complexity of this task. We have developed synthetic polymer formulations for in vivo siRNA delivery named Dynamic PolyConjugates™ (DPCs) that are designed to mimic the features viruses possess for efficient delivery of their nucleic acids. These include small size, long half-life in circulation, capability of displaying distinct host cell tropism, efficient receptor binding and cell entry, disassembly in the endosome and subsequent release of the nucleic acid cargo to the cytoplasm. Here we present an example of this delivery platform composed of a hepatocyte-targeted endosome-releasing agent and a cholesterol-conjugated siRNA (chol-siRNA). This delivery platform forms the basis of ARC-520, an siRNA-based therapeutic for the treatment of chronic hepatitis B virus (HBV) infection. In this chapter, we provide a general overview of the steps in developing ARC-520 and detailed protocols for two critical stages of the discovery process: (1) verifying targeted in vivo delivery to hepatocytes and (2) evaluating in vivo drug efficacy using a mouse model of chronic HBV infection.

Kinetics of hepatitis B surface antigen loss in patients with HBeAg-positive chronic hepatitis B treated with tenofovir disoproxil fumarate

BACKGROUND & AIMS

In a study of 266 chronic hepatitis B e antigen (HBeAg)-positive patients, 23 experienced hepatitis B surface antigen (HBsAg) loss with up to 5 years of tenofovir disoproxil fumarate (TDF) treatment. HBsAg kinetics in patients with and without HBsAg loss and predictors of HBsAg loss were evaluated.

METHODS

HBsAg levels were quantified every 12 weeks. A multivariable regression analysis, involving prespecified baseline characteristics and on-treatment response parameters, was performed; a stepwise procedure identified independent predictors of HBsAg loss.

RESULTS

Among patients with HBsAg loss, 14 (61%), 1 (4%), 0 and 7 (30%) were genotypes A through D, respectively; 1 (4%) was genotype F. HBsAg loss was preceded by viral suppression (HBV DNA <29 IU/ml; n=23) and HBeAg loss (n=19). Among treated patients the strongest independent predictors of HBsAg loss were Caucasian race with genotype A/D and ⩽4 years of infection (HR=14.3, 95% confidence interval [CI] 4.7-43.4; p<0.0001) and an HBsAg decline of ⩾1 log10 IU/ml at week 24 (HR=13.7, 95% CI 5.6-33.7; p<0.0001). Among TDF-treated patients, a reduction in HBsAg level of ⩾1-log10 by week 12 or 24 had a positive predictive value of 35%-45%, respectively, and a negative predictive value of 94%-97%, respectively.

CONCLUSIONS

HBsAg loss in HBeAg-positive patients receiving TDF involves a chronology of virologic and serologic responses; patients with HBV genotypes A or D and a rapid early decline in HBsAg are more likely to lose HBsAg.

Hepatitis B surface antigen seroclearance: Relationship to hepatitis B e-antigen seroclearance and hepatitis B e-antigen-negative hepatitis

OBJECTIVES

The objective of this study was to determine factors associated with hepatitis B surface antigen (HBsAg) seroclearance after hepatitis B e-antigen (HBeAg) seroclearance.

METHODS

This is a cohort study of HBeAg-positive patients with HBeAg seroclearance. Factors associated with subsequent HBsAg seroclearance were examined.

RESULTS

A total of 775 patients were included. At 1, 5, 10, 15, 20, and 25 years after HBeAg seroclearance, the HBsAg seroclearance rate was 0.3, 1.3, 3.0, 8.9, 15.7, and 23.6%, respectively. The rate of HBsAg seroclearance was highest in those who underwent spontaneous HBeAg seroclearance and required no treatment afterward (group 1), compared with those who underwent treatment-induced HBeAg seroclearance (group 2), and those who required antiviral therapy after spontaneous HBeAg seroclearance (group 3). At 25 years after HBeAg seroclearance, the HBsAg seroclearance rate was 38.0, 14.9, and 0% in groups 1, 2, and 3, respectively (P<0.001). There was no difference in the rate of HBsAg seroclearance between those who received interferon-based therapy compared with nucleos(t)ide analogs. The median HBV DNA level was similar between those with and without HBsAg seroclearance. The median HBsAg level was significantly lower in those who had HBsAg seroclearance compared with those who did not achieve loss of HBsAg (2.81 vs. 3.52 log IU/ml, respectively, P=0.009). The area under receiver operating characteristic curve for HBsAg at 1 year after HBeAg seroclearance for predicting HBsAg seroclearance was 0.742, with an optimal cutoff of 751 IU/ml.

CONCLUSIONS

Spontaneous HBeAg seroclearance without need for subsequent antiviral therapy was associated with the highest rate of subsequent HBsAg seroclearance. Lower HBsAg levels were also associated with higher chance of HBsAg seroclearance.