The role of quantitative hepatitis B surface antigen revisited

Role of quantitative hepatitis B surface antigen levels in predicting liver biopsy time in treatment-naive chronic hepatitis B patients

Aim of the study

The quantitative hepatitis B surface antigen (qHBsAg) level indicates the amount of transcriptional activity of covalently closed circular DNA (cccDNA) and integrated DNA in hepatocytes which plays a role in development of chronic hepatitis B (CHB) and may help decide whether the treatment is necessary or not. The aim of this study is to evaluate the association between serum qHBsAg levels and viral replication and stage of liver fibrosis in treatment-naive CHB patients and to determine the role of qHBsAg levels in predicting when liver biopsy is necessary.

Material and methods

967 patients were included in the study. Because of refusal of liver biopsy the study was conducted on 123 patients. The association between qHBsAg levels with HBV DNA, a-fetoprotein, fibrosis stage and histology activity index was evaluated.

Results

Of the patients, mean age was 48 ±11.2 years and 56.1% were male. We found that patients with HBV DNA ≥ 2000 IU/ml had a higher qHBsAg titer in comparison with HBV DNA < 2000 IU/ml. However, there was no relationship between qHBsAg titer and liver necroinflammation or fibrosis stage.

Conclusions

Monitoring of qHBsAg together with HBV DNA may be helpful in CHB management. However, qHBsAg level does not provide knowledge about the timing of biopsy or the decision of CHB treatment.

Circulating serum HBsAg level is a biomarker for HBV-specific T and B cell responses in chronic hepatitis B patients

Chronic hepatitis B (CHB) infection functional cure is defined as sustained loss of HBsAg and several therapeutic strategies are in clinical development designed to pharmacologically reduce serum HBsAg, break immune tolerance, and increase functional cure rates. However, little is known about pre-treatment HBsAg levels as an indicator of HBV immune potential. Here, we compared the phenotypes and HBV-specific response of lymphocytes in CHB patients stratified by serum HBsAg levels <500 (HBs^lo) or >50,000 IU/ml (HBs^hi) using immunological assays (flow cytometry, ICS, ELISPOT). HBs^hi patients had significantly higher expression of inhibitory PD-1 on CD4⁺ T cells, particularly among TEMRA subset, and higher FcRL5 expression on B cells. Upon HBcAg(core) or HBsAg(env)-stimulation, 85% and 60% of HBs^lo patients had IFNγ⁺TNFα⁺ and IFNγ⁺ IL2⁺ CD4⁺ T cell responses respectively, in comparison to 33% and 13% of HBs^hi patients. Checkpoint blockade with αPD-1 improved HBV-specific CD4⁺ T cell function only in HBs^lo patients. HBsAg-specific antibody-secreting cells (ASCs) response was not different between these groups, yet αPD-1 treatment resulted in significantly higher fold change in ASCs among patients with HBsAg <100 IU/ml compared to patients with HBsAg >5,000 IU/ml. Thus, serum HBsAg correlates with inhibitory receptor expression, HBV-specific CD4⁺ T cell responses, and augmentation by checkpoint blockade.

Quantitation of large, middle and small hepatitis B surface proteins in HBeAg-positive patients treated with peginterferon alfa-2a

BACKGROUND & AIMS

Hepatitis B virus (HBV) contains three viral surface proteins, large, middle and small hepatitis B surface protein (LHBs, MHBs, SHBs). Proportions of LHBs and MHBs are lower in patients with inactive vs active chronic infection. Interferon alfa may convert hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) to an inactive carrier state, but prediction of sustained response is unsatisfactory. The aim of this study was to test the hypothesis that quantification of MHBs and LHBs may allow for a better prognosis of therapeutic response than total hepatitis B surface antigen (HBsAg) concentration.

METHODS

Hepatitis B surface proteins were measured before and during peginterferon alfa-2a therapy in serum from 127 Asian patients with HBeAg-positive CHB. Sustained response was defined as HBeAg seroconversion 24 weeks post-treatment.

RESULTS

Mean total HBs levels were significantly lower in responders vs nonresponders at all time points (P < .05) and decreased steadily during the initial 24 weeks treatment (by 1.16 vs 0.86 ng/mL in responders/nonresponders respectively) with unchanged relative proportions. Genotype B had a two-fold higher proportion of LHBs than genotype C (13% vs 6%). HBV DNA, HBeAg, HBsAg and HBs protein levels predicted response equally well but not optimally (area under the receiver operating characteristic curve values >0.70).

CONCLUSIONS

Hepatitis B surface protein levels differ by HBV genotype. However, quantification of HBs proteins has no advantage over the already established HBsAg assays to predict response to peginterferon alfa-2a therapy in HBeAg-positive patients.

Hepatitis B and Pregnancy: Virologic and Immunologic Characteristics

The hepatitis B virus (HBV) is an important human pathogen. Unvaccinated infants infected through mother-to-child transmission (MTCT) are at >95% risk of developing serum hepatitis B surface antigen-positive chronic hepatitis B (CHB). Despite complete passive-active HBV immunoprophylaxis, approximately 10% of infants born to mothers who are highly viremic develop CHB, and thus maternal treatment with nucleos(t)ide analogs (tenofovir disoproxil fumarate, lamivudine, or telbivudine) is recommended in the third trimester of pregnancy to reduce MTCT risk. Viral rebound usually occurs after stopping treatment and, in the context of maternal immunologic reconstitution postpartum, can also precipitate host immune-mediated hepatic (biochemical) flares. In this article, we review the epidemiology of HBV MTCT, discuss management and potential mechanisms of HBV vertical transmission, and highlight recent studies on virologic and immunologic aspects of hepatitis B in pregnancy and postpartum.

Unresolved issues of immune tolerance in chronic hepatitis B

During the natural course of chronic hepatitis B virus infection, immune-tolerant phase is characterized by high viral replication, the presence of HBV e antigen (HBeAg), and normal or minimally elevated serum alanine aminotransferase. Immune-tolerant phase is usually regarded as a benign course of the disease. International guidelines recommend observation rather than treatment during immune-tolerant phase. In this article, we review unresolved issues related to the definition of true immune-tolerant phase and the benefit of antiviral treatment. Defining true immune-tolerant phase requires a careful approach and long-term follow-up. In previous studies, many patients were misclassified as being immune-tolerant phase. Noninvasive methods of assessing fibrosis are warranted for patients in the immune-tolerant phase. Yet, there has been controversy over the benefit and harm of antiviral treatment for immune-tolerant phase patients. Thus, further larger scale studies are needed to investigate the prognosis of patients in true immune-tolerant phase and their need for antiviral therapy.

Dynamics of HBV surface antigen related end points in chronic hepatitis B infection: a systematic review and meta-analysis

BACKGROUND

In chronic hepatitis B (CHB) treatment, hepatitis B surface antigen (HBsAg) is regarded as a promising clinical end point associated with long-term clinical outcomes. We performed a meta-analysis to characterize the dynamics and influencing factors of HBsAg.

METHODS

Literature search was conducted through PubMed from January 1995 to May 2015 for papers reporting HBsAg in patients receiving various antiviral treatments. We conducted weighted linear regression to select for potential influencing factors on maximum HBsAg loss percentage, and subgroup analysis to calculate the pooled estimates of maximum HBsAg loss and seroconversion percentage following treatment of interferon (IFN), nucleoside analogue (NUC) or combination therapies (NUC+IFN), respectively. Study heterogeneity was assessed through sensitivity test and I-square statistics.

RESULTS

We collected data from 24 papers involving 6,674 adult CHB patients. In most studies, average HBsAg level decreased during treatment but relapsed after treatment cessation, while HBsAg loss or seroconversion percentage continued to increase or remained stable after treatment cessation. No strong relationship was observed between maximum HBsAg change and its baseline level. The pooled estimates of maximum HBsAg loss percentage for IFN (5.3%, 2.7-7.9%) and NUC+IFN (5.2%, 3.1-7.4%) were significantly higher than that of NUC (0.93%, 0.29-1.6%). Higher maximum HBsAg loss percentage is associated with longer peak time. Pooled maximum HBsAg seroconversion percentage estimates were 1.6%, 0.56% and 6.2% for IFN, NUC and NUC+IFN.

CONCLUSIONS

With respect to HBsAg lowering, this meta-analysis confirmed the importance of longer treatment duration and addition of IFN, which revealed the potential value of immune-based therapies.

Quantitative Hepatitis B Surface Antigen Predicts Hepatitis B Transmission in Infants Born to e Antigen-positive Mothers

GOALS

This study aimed to explore whether quantitative surface antigen [hepatitis B surface antigen (HBsAg)] can be used as a surrogate marker of hepatitis B virus (HBV) DNA to predict hepatitis B transmission before the first hepatitis vaccine dose in infants born to hepatitis B e antigen (HBeAg)-positive pregnant women.

BACKGROUND

Currently, HBV transmission persistently occurs worldwide, especially in infants born to e antigen (HBeAg)-positive highly viremic mothers. However, due to high cost, the extensive use of viral load testing to identify these high-risk mothers is limited.

MATERIALS AND METHODS

In total of 275 HBeAg-positive pregnant women paired with 280 infants were enrolled in this study. Quantitative HBsAg and HBV DNA levels were measured in the third trimester. Spearman rank correlation was used to assess the correlation between HBsAg levels and viral load, and multivariate logistic regression to identify factors related to HBV transmission in infants.

RESULTS

Among 280 infants included, 15 (5.4%) infants were infected with HBV. In this study, we observed that quantitative HBsAg was positively correlated with maternal viral load (r=0.70, P<0.001) and highly predicted HBV transmission in infants born to HBeAg-positive mothers with area under the curve of 0.76 (95% confidence interval, 0.71-0.81). The optimum threshold HBsAg levels above 4.6 log10 IU/mL to predict HBV transmission in infants had a sensitivity of 80.0%, specificity of 67.9%.

CONCLUSIONS

Quantitative HBsAg could be used as a surrogate marker of HBV DNA levels to predict hepatitis B transmission occurring before the injection of first-dose vaccine in infants born to e antigen-positive mothers.

Effect of nucleos(t)ide analogue on serum HBsAg level in chronic hepatitis B patients: A 3-years study

AIM

We aim to explore the effects of nucleos(t)ide analogues (NUCs) on the changes of HBsAg in chronic hepatitis B (CHB) patients.

METHODS

A total of 264 CHB patients were enrolled in our study. All of them were treated with NUCs for at least three years. Quantification of HBsAg levels were measured by Elecsys HBsAg II.

RESULTS

Although HBsAg levels were significantly higher in HBeAg seropositive CHB patients at baseline than in HBeAg seronegative CHB patients (3.84 ± 0.82 vs 3.21 ± 0.59 IU/mL), HBsAg levels declined more rapidly in the HBeAg seropositive group (P < 0.001). In HBeAg-positive CHB patients, HBsAg level in the telbivudine (LDT)-treated group was 3.68 ± 0.56 IU/mL after 52-week of treatment, which was significantly higher than that in lamivudine (LAM)-treated group (P = 0.009). Multivariable analyses showed that baseline HBV DNA viral load (OR = 0.75, P = 0.018), baseline ALT level (OR = 0.99, P = 0.015), and baseline HBsAg level (OR = 0.188, P < 0.001) were independent factors that affected HBsAg decline in HBeAg seropositive CHB patients. For HBeAg seronegative CHB patients, the average of serum HBsAg levels in LAM-, LdT-, adefovir (ADV)-, and entecavir (ETV)-treated groups at baseline, 52 weeks, 104 weeks, and 156 weeks were similar. Multivariable analyses showed that only baseline HBV DNA level (OR = 0.56, P = 0.020) and baseline HBsAg level (OR = 0.57, P = 0.012) were independent factors that affected HBsAg decline in HBeAg seronegative patients with CHB. Baseline HBV DNA level (OR = 0.72, P = 0.010) and baseline HBsAg level (OR = 0.19, P < 0.001) were independent factors that affected all CHB patients.

CONCLUSIONS

CHB Patients who had received NUCs antiviral treatment showed a slow but significant decrease in serum HBsAg level. Long-term monitoring and continuous antiviral treatment are necessary, especially for those patients with risk factors associated with HBsAg decline.

Baseline and kinetics of serum hepatitis B virus RNA predict response to pegylated interferon-based therapy in patients with hepatitis B e antigen-negative chronic hepatitis B

Serum hepatitis B virus (HBV) RNA has emerged as a novel biomarker of treatment response. This study aimed to investigate the role of this marker in predicting long-term outcome of patients with hepatitis B e antigen (HBeAg)-negative chronic hepatitis B (CHB) receiving pegylated interferon (PEG-IFN)-based therapy. Serial serum samples from 91 patients with HBeAg-negative CHB previously treated with PEG-IFN alone or combined with entecavir in a randomized trial were retrospectively analysed. HBV RNA quantification was examined by droplet digital PCR. At the end of 3 years post-treatment follow-up, maintained virological response (MVR, HBV DNA < 2000 IU/mL), and hepatitis B surface antigen (HBsAg) clearance were achieved in 37.4% (34/91) and 7.7% (7/91), respectively. Baseline serum HBV RNA concentrations correlated with HBV DNA and covalently closed circular DNA but did not correlate with HBsAg levels. Multiple regression analysis showed that pre-treatment HBV RNA and HBsAg were independently associated with MVR and HBsAg clearance. Baseline HBV RNA (cut-off 2.0 log₁₀  copies/mL) had a positive predictive value (PPV) and a negative predictive value in predicting MVR of 80.8% and 80.0%, respectively. At the same cut-off value, PPV and NPV for predicting HBsAg clearance were 30.8% and 95.4%, respectively. At week 12 during therapy, HBV RNA level ≥ 2 log₁₀ copies/mL displayed high NPVs of achieving MVR and HBsAg clearance (95% and 100%, respectively). In conclusion, the measurement of HBV RNA prior to PEG-IFN-based therapy could identify patients with high probability of MVR. In addition, HBV RNA kinetics may serve as a promising "stopping rule" in patients infected with HBV genotypes B or C.

Emerging tools in the changing landscape of chronic hepatitis B management

Introduction: The availability of a preventative vaccine, interferon, and nucleos(t)ide analogs have provided progress in the control of chronic hepatitis B (CHB). Despite this, it remains a major contributor to global morbidity and mortality. Developments in our understanding of the pathogenesis of CHB and the emergence of new therapies are paving the way, as we move toward HBV cure.Areas covered: We performed bibliographical searches of online databases to review the literature regarding conventional disease phases of CHB. We provide the latest evidence challenging the perception of the natural history of CHB, noting that previously considered quiescent disease phases may not represent benign disease states devoid of progression. We explore the use of potential novel immunological and viral tools which should enhance disease stratification and management decisions in the coming years. Finally, we discuss the timing of treatment and how this could be initiated earlier to improve treatment outcomes, preventing sequelae of chronic infection.Expert opinion: The treatment paradigm in CHB is set to change with multiple novel agents in early phase clinical trials with the aim of a functional cure. An improved understanding of disease pathogenesis and the timing of treatment will be critical to the success of new therapies.

HBV Genome and Life Cycle

Chronic hepatitis B virus (HBV) infection remains to be a serious threat to public health and is associated with many liver diseases including chronic hepatitis B (CHB), liver cirrhosis, and hepatocellular carcinoma. Although nucleos(t)ide analogues (NA) and pegylated interferon-α (Peg-IFNα) have been confirmed to be efficient in inhibiting HBV replication, it is difficult to eradicate HBV and achieve the clinical cure of CHB. Therefore, long-term therapy has been recommended to CHB treatment under the current antiviral therapy. In this context, the new antiviral therapy targeting one or multiple critical steps of viral life cycle may be an alternative approach in future. In the last decade, the functional receptor [sodium-taurocholate cotransporting polypeptide (NTCP)] of HBV entry into hepatocytes has been discovered, and the immature nucleocapsids containing the non- or partially reverse-transcribed pregenomic RNA, the nucleocapsids containing double-strand linear DNA (dslDNA), and the empty particles devoid of any HBV nucleic acid have been found to be released into circulation, which have supplemented the life cycle of HBV. The understanding of HBV life cycle may offer a new instruction for searching the potential antiviral targets, and the new viral markers used to monitor the efficacy of antiviral therapy for CHB patients in the future.

Guidance for design and endpoints of clinical trials in chronic hepatitis B - Report from the 2019 EASL-AASLD HBV Treatment Endpoints Conference

Representatives from academia, industry, regulatory agencies, and patient groups convened in March 2019 with the primary goal of developing agreement on chronic hepatitis B virus (HBV) treatment endpoints to guide clinical trials aiming to 'cure' HBV. Agreement among the conference participants was reached on some key points. 'Functional' but not sterilizing cure is achievable and should be defined as sustained HBsAg loss in addition to undetectable HBV DNA 6 months post-treatment. The primary endpoint of phase 3 trials should be functional cure; HBsAg loss in ≥30% of patients was suggested as an acceptable rate of response in these trials. Sustained virologic suppression (undetectable serum HBV DNA) without HBsAg loss, 6 months after discontinuation of treatment would be an intermediate goal. Demonstrated validity in predicting sustained HBsAg loss was considered the most appropriate criterion for the approval of new HBV assays to determine efficacy endpoints. Clinical trials aimed at HBV functional cure should initially focus on patients with HBeAg-positive and HBeAg-negative chronic hepatitis, treatment-naïve or virally suppressed on nucleos(t)ide analogues. A hepatitis flare associated with increase in bilirubin or INR should prompt temporary or permanent cessation of investigational treatment. New treatments must be as safe as existing nucleos(t)ide analogues. The primary endpoint for phase 3 trials for hepatitis D virus (HDV) co-infection should be undetectable serum HDV RNA 6 months after stopping treatment. On treatment HDV RNA suppression associated with normalization of ALT is considered an intermediate goal. CONCLUSION: For HBV 'functional cure', sustained HBsAg loss with undetectable HBV DNA after completion of treatment is the primary goal and sustained undetectable HBV DNA without HBsAg loss after stopping treatment an intermediate goal.

Insulin Resistance Associated Disorders Pivoting Long-Term Hepatitis B Surface Antigen Decline During Entecavir Therapy

Insulin resistance associated disorders (IRAD), including prediabetes, type 2 diabetes mellitus (T2DM), and fatty liver are significant risk factors of liver-related death in chronic hepatitis B (CHB). However, their relationship remains unclear. We aimed to evaluate how IRAD influence the kinetics of serum hepatitis B surface antigen (HBsAg) in patients with CHB during long-term entecavir treatment. We enrolled 140 patients with CHB receiving at least 3 years of consecutive entecavir treatment in this retrospective study. A linear mixed effects model was adopted to examine the effects of variables and their interaction over time on the HBsAg trajectory. Furthermore, we acquired cytokine profiles and baseline fibrosis-4 index (FIB-4) scores for in-depth analysis. The median treatment time was 6.90 (4.47–9.01) years. Multivariate analysis revealed that older patients or those with prediabetes or T2DM had a significantly slower HBsAg decline over time (p = 0.0001 and p < 0.0001, respectively). Conversely, advanced fatty liver engendered a more rapid HBsAg decrease (p = 0.001). Patients with prediabetes or T2DM possessed higher IP-10 levels six years after entecavir therapy (p = 0.013). Compared to patients without prediabetes or T2DM, diabetic patients had more unfavorable features at the baseline, especially higher FIB-4 scores. Prediabetes or T2DM delays the clearance of HBsAg, but advanced hepatic fatty change counterbalances the effect. Additionally, IRAD could cause hepatic sequelae in CHB through immune-metabolic pathways.

An Automated, Quantitative, and Multiplexed Assay Suitable for Point-of-Care Hepatitis B Virus Diagnostics

Hepatitis B virus (HBV) infection has a global reach with high prevalence in resource-limited areas like China and Africa. HBV patients in these areas have limited access to the currently used, costly HBV assays, which are performed in centralized clinical laboratories using single-plexed assays with bulky and expensive instruments. We aim to overcome these limitations by developing a simple and affordable HBV diagnostic platform to allow for timelier diagnosis and intervention of HBV infection. Using giant magnetoresistive (GMR) biosensor chips, we developed an automated and multiplexed quantitative platform for the measurement of a panel of HBV serology markers, including HBV “e” antigen (HBeAg), HBV surface antigen (HBsAg), and the antibody against HBsAg (anti-HBs). Our assay platform was able to detect each HBV marker with high specificity and sensitivity (with three orders of magnitude in dynamic range for each marker). Blinded analysis of HBV patient sera showed excellent correlation between our multiplexed quantitative HBsAg results and the qualitative results obtained using FDA-approved immunoassays, as well as those obtained using quantitative, single-plexed, enzyme-linked immunosorbent assays (ELISAs). The portable, automated, multiplexed, quantitative HBV serology assay platform we designed shows great promise as a more accessible alternative for HBV screening, diagnosis, and treatment monitoring.

An update on the management of chronic hepatitis D

Hepatitis D virus (HDV) infection is associated with severe liver-related morbidity and mortality. The prevalence of HDV is rising especially among people who abuse drugs and immigrants from endemic areas. Reliable diagnostic assays with enhanced sensitivity and specificity are essential for screening at-risk populations. Until recently, interferon has been the only treatment for hepatitis D. Its efficacy is, however, limited and it is associated with significant side effects. A number of novel antiviral agents that target various stages of the HDV life cycle show promising results. They are currently in different phases of clinical development. This review focuses on the changing epidemiology, novel therapeutic agents, and updated management of chronic hepatitis delta.

Early Hepatitis B Surface Antigen Seroclearance Following Antiviral Treatment in Patients with Reactivation of Resolved Hepatitis B

BACKGROUND AND AIMS

Long-term results on hepatitis B virus (HBV) reactivation in patients with resolved infection during anti-cancer therapy are unknown. This study investigated long-term risk and therapeutic endpoints including hepatitis B surface antigen (HBsAg) seroclearance following antiviral therapy in patients developing reactivation of resolved HBV.

METHODS

The study included 528 consecutive HBsAg-negative/hepatitis B core antibody-positive patients who underwent rituximab treatment or hematopoietic stem cell transplantation (HSCT) between 2006 and 2016. Long-term outcomes of patients with reactivation after antiviral therapy were examined in comparison with 37 HBsAg-positive chronic carriers under the same medical settings.

RESULTS

The 7-year cumulative rate of HBV reactivation was 10.8% and 57.9% in patients receiving rituximab treatment and HSCT, respectively. After antiviral initiation, patients with reactivation of resolved HBV showed significantly higher 1-year cumulative rates of hepatitis B e antigen seroconversion (69.2% vs. 22.6%, P = 0.008) and HBsAg seroclearance (61.8% vs. 3.3%, P < 0.001) than chronic HBsAg carriers. Reactivation of resolved HBV was independently predictive of HBsAg seroclearance in a combined group of reactivated patients and chronic HBsAg carriers. Low viral load at reactivation was predictive of HBsAg seroclearance in reactivated patients. The majority of patients with HBsAg seroclearance developed anti-HBs. None of the reactivated patients who achieved HBsAg seroclearance relapsed after cessation of antiviral therapy.

CONCLUSIONS

HBsAg seroclearance rapidly occurs following antiviral therapy for reactivation of resolved HBV infection, suggesting distinct clinical phenotypes as well as shorter duration of HBV infection associated with this particular disease setting-HBV reactivation.

Soluble immune markers in the different phases of chronic hepatitis B virus infection

Chronic hepatitis B virus (HBV) infection may follow four different consecutive phases, which are defined by virology as well as biochemical markers and differ in terms of prognosis and need for antiviral treatment. Currently, host responses reflected by immune markers are not considered in this definition. We aimed to study soluble immune markers and their distribution in different phases of chronic HBV infection. In this cross-sectional retrospective study, we investigated a panel of 14 soluble immune markers (SIM) including CXCL10 in 333 patients with chronic HBV infection. In a small cohort of HBeAg positive patients we analyzed SIM before and after HBeAg seroconversion and compared seroconverters to patients with unknown outcome. Significant differences were documented in the levels of several SIM between the four phases of chronic HBV infection. The most pronounced difference among all investigated SIM was observed for CXCL10 concentrations with highest levels in patients with hepatitis. TGF-β and IL-17 revealed different levels between HBeAg negative patients. HBeAg positive patients with HBeAg seroconversion presented higher amounts of IL-12 before seroconversion compared to HBeAg positive patients with unknown follow up. SIM such as CXCL10 but also IL-12, TGF-β and IL-17 may be useful markers to further characterize the phase of chronic HBV infection.

Hepatitis B core-related antigen monitoring during peginterferon alfa treatment for HBeAg-negative chronic hepatitis B

Serum Hepatitis B core-related antigen (HBcrAg) level moderately correlates with cccDNA. We examined whether HBcrAg can add value in monitoring the effect of peginterferon (PEG-IFN) therapy for HBeAg-negative chronic hepatitis B (CHB) infection. Thus, serum HBcrAg level was measured in 133 HBeAg-negative, mainly Caucasian CHB patients, treated with 48 weeks of PEG-IFN alfa-2a. We assessed its association with response (ALT normalization & HBV DNA < 2000 IU/mL) at week 72. HBcrAg level strongly correlated with HBV DNA level (r = 0.8, P < 0.001) and weakly with qHBsAg and ALT (both r = 0.2, P = 0.01). At week 48, mean HBcrAg decline was -3.3 log U/mL. Baseline levels were comparable for patients with and without response at week 72 (5.0 vs 4.9 log U/mL, P = 0.59). HBcrAg decline at week 72 differed between patients with and without response (-2.4 vs -1.0 log U/mL, P = 0.001), but no cut-off could be determined. The pattern of decline in responders resembled that of HBV DNA, but HBcrAg decline was weaker (HBcrAg -2.5 log U/mL; HBV DNA: -4.0 log IU/mL, P < 0.001). For early identification of nonresponse, diagnostic accuracy of HBV DNA and qHBsAg decline at week 12 (AUC 0.742, CI-95% [0.0.629-0.855], P < 0.001) did not improve by adding HBcrAg decline (AUC 0.747, CI-95% [0.629-0.855] P < 0.001), nor by replacing HBV DNA decline by HBcrAg decline (AUC 0.754, CI-95% [0.641-0.867], P < 0.001). In conclusion, in Caucasian patients with HBeAg-negative CHB, decline of HBcrAg during PEG-IFN treatment was stronger in patients with treatment response. However, HBcrAg was not superior to HBV DNA and qHBsAg in predicting response during PEG-IFN treatment.

Understanding the patient population and test utilization for hepatitis B virus testing

BACKGROUND

Hepatitis B virus (HBV) infection remains a global concern with different epidemiologies due to several factors including migration, vaccination policies, and new antiviral treatment regimens. It is important to understand the characteristics of a patient population, including the prevalence of diseases, and to assess test utilization to understand and evaluate the clinical performance of laboratory tests and to improve the quality of clinical laboratories.

MATERIALS AND METHODS

In this study, we evaluated serologic and virologic laboratory tests including hepatitis B surface antigen, hepatitis B surface antibody, hepatitis B envelope antigen (HBeAg), hepatitis B envelope antibody, and HBV DNA in Korean adults who were exposed to HBV.

RESULTS

During the 1-year study period, we obtained 22 750 specimens from 17 523 adult Korean patients (>18.0 years; 9894 males and 7629 females) with a median age of 50.1 years (interquartile range, 42.2-58.2 years). Among them, five serologic and virologic laboratory tests were performed for 1340 (5.9%) specimens from 1172 adult Korean patients (>18.0 years; 647 males and 525 females) with a median age of 46.8 years (range, 19.0-84.5 years). The prevalence of serologic and virologic tests indicating several clinical situations was evaluated. The correlation coefficient between HBV DNA and HBeAg was ρ = 0.85 (P < .0001). However, 51.9% (695/1340) of samples did not show agreement between the two test results.

CONCLUSIONS

Analysis of the prevalence of patients categorized into five serologic and virologic laboratory results would be helpful to expand our knowledge about patient population characteristics and to improve test utilization.

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

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

Divergent preS Sequences in Virion-Associated Hepatitis B Virus Genomes and Subviral HBV Surface Antigen Particles From HBV e Antigen-Negative Patients

Background

Hepatitis B virus (HBV) surface proteins (HBsAg) coat the viral particle and form subviral particles (SVPs). Loss of HBsAg represents a functional cure and is an important treatment goal.

Methods

We analyzed the impact of the HBV genotypes A-E and pre-S mutations on SVP expression in hepatitis B virus e antigen (HBeAg)-negative chronic HBV-infected patients. A HBV genome harboring a preS1-deletion was analyzed in hepatoma cells.

Results

We observed a genotype-specific ratio of the 3 surface proteins (SHBs/MHBs/LHBs), reflecting differences in the morphology and composition of SVPs. Deletions/mutations in the preS1/preS2 domain, detected in released viral genomes, did not affect the molecular weight of MHBs and LHBs in these patients. In contrast, LHB molecular weight was altered in vitro using an HBV genome harboring a preS1-deletion derived from one of these patients.

Conclusion

Differences in composition of SVPs may result in genotype-specific immunogenicity and pathogenesis. In the patients with preS-mutations, secreted HBsAg and released viral genomes cannot be derived from the same genetic source. As viral genomes are derived from covalently closed circular DNA (cccDNA), HBsAg is presumably derived from integrated DNA. This important HBsAg source should be considered for novel antiviral strategies in HBeAg-negative chronic HBV-infected patients.

A Global View to HBV Chronic Infection: Evolving Strategies for Diagnosis, Treatment and Prevention in Immunocompetent Individuals

Hepatitis B Virus (HBV) is a significant public health challenge. Around 250 million people live with chronic HBV infection. With a global approach to this issue, we focus on new perspective in diagnosis, management and prevention of HBV chronic infection. Precise diagnosis of HBV status is crucial to guide patient management. Although available drugs reduce the risk of liver disease progression, they are not able to definitely eradicate HBV, and new therapeutic options are urgently needed. Thus, prevention of HBV infection is still the most effective strategy to achieve the control of the disease. Key aspects of prevention programs include surveillance of viral hepatitis, screening programs and immunization strategies. In spite of the high success rate of licensed HBV vaccines, a need for improved vaccine persists, especially in order to provide coverage of current non-responders.

Therapeutic strategies for hepatitis B virus infection: towards a cure

Chronic hepatitis B virus (HBV) infection is a common cause of liver disease globally, with a disproportionately high burden in South-East Asia. Vaccines and nucleoside or nucleotide drugs are available and reduce both new infection rates and the development of liver disease in HBV-positive persons who adhere to long-term suppressive treatment. Although there is still considerable value in optimizing access to virus-suppressing regimens, the scientific and medical communities have embarked on a concerted journey to identify new antiviral drugs and immune interventions aimed at curing infection. The mechanisms and drug targets being explored are diverse; however, the field universally recognizes the importance of addressing the persistence of episomal covalently closed circular DNA, the existence of integrated HBV DNA in the host genome and the large antigen load, particularly of hepatitis B surface antigen. Another major challenge is to reinvigorate the exhausted immune response within the liver microenvironment. Ultimately, combinations of new drugs will be required to cure infection. Here we critically review the recent literature that describes the rationale for curative therapies and the resulting compounds that are being tested in clinical trials for hepatitis B.

The modulation of HBsAg level by sI126T is affected by additional amino acid substitutions in the S region of HBV

The hepatitis B surface antigen (HBsAg) is a vital serum marker for hepatitis B virus (HBV) infection. Amino acid (AA) substitutions in small hepatitis B surface protein (SHBs) are known to affect HBsAg level. However, how the genetic backbones of SHBs sequences would affect the roles of a specific AA substitution on HBsAg level remains unclear. In this study, we found that sI126 had a very high substitution detection rate of 17.54% (40/228) in untreated chronic hepatitis B cohort with subgenotype C2 HBV infection. Among different substitution types at sI126, the sI126T (N = 28) was found to be associated with significantly lower serum HBsAg level. Clone sequencing revealed that sI126T-harboring SHBs sequences had varied genetic backbones with zero to nine additional AA substitutions. Thus, we constructed 24 HBsAg expression plasmids harboring sI126T without (plasmid 1, P1) or with (P2-P24) additional AA substitution(s) and studied them in the HepG2 cells. The HBsAg levels were determined by both ELISA and Western blot. In vitro experiments showed that P1 significantly reduced HBsAg level and its secretion (p < .05), however, P2-P24 showed various extracellular and intracellular HBsAg levels. No significant differences were detected among the HBsAg mRNA levels of nine representative mutant plasmids. Our findings suggest that the modulation of HBsAg level by sI126T is affected by additional AA substitution(s) in the S region of HBV. The effects of AA combination substitutions in SHBs sequences on HBsAg levels are worthwhile for more attentions in terms of HBV biology and its clinical application.

Next generation sequencing identifies baseline viral mutants associated with treatment response to pegylated interferon in HBeAg-positive chronic hepatitis B

Current data of hepatitis B virus (HBV) variants associated with treatment outcome identified by next generation sequencing (NGS) are limited. This study was aimed at determining the role of baseline sequence variations in the enhancer II (EnhII), basal core promotor (BCP) and pre-core (PC) regions of HBV genotype C in patients treated with pegylated interferon (PEG-IFN). Patients with HBeAg-positive chronic hepatitis B (CHB) treated with 48-week PEG-IFN were enrolled. Combined response (CR) at week 96 was defined by HBeAg seroconversion plus HBV DNA < 2000 IU/mL and HBsAg < 1000 IU/mL. Pre-treatment viral mutations were characterized by Sanger sequencing and NGS (Miseq Illumina platform). Among 47 patients (32 male, mean age 32.4 years), CR was achieved in 12 (25.5%) individuals. Overall, NGS was superior to Sanger sequencing in detecting mutations (61.7% vs. 38.3%, P < 0.001). Based on NGS, the prevalence of T1753V (T1753C/A/G) and A1762T/G1764A variants were significantly lower in responders compared to non-responders (8.3% vs. 51.4%, P = 0.009 and 33.3% vs. 68.6%, P = 0.032, respectively). No significant difference between groups was found regarding C1653T and G1896A mutants. The absence of T1753V and A1762T/G1764A mutations were factors associated with CR (OR 11.65, 95%CI 1.36-100.16, P = 0.025, and OR 4.36, 95%CI 1.08-17.63, P = 0.039, respectively). The existence of pre-treatment T1753V, A1762T/G1764A mutations and their combination yielded negative predictive values of 94.7%, 85.7% and 93.8%, respectively. The presence of HBV mutants in the BCP region determined by NGS at baseline was associated with poor treatment outcome in patients with HBeAg-positive CHB receiving PEG-IFN.

Characteristics of an Outpatient Cohort with HBeAg-Negative Chronic Hepatitis B

BACKGROUND:

Patients with hepatitis Be antigen-negative chronic hepatitis B (HBeAg-negative CHB), and patients’ inactive carriers (IC) have similar laboratory and serologic characteristics and are not always easy to distinguish.

AIM:

To characterise hepatitis Be antigen (HBeAg) negative chronic hepatitis B cohort based on their laboratory and virology evaluations at one point of time.

METHODS:

A prospective non-randomized study was conducted on 109 patients with HBeAg negative chronic hepatitis B treated as outpatients at the Clinic for Infectious Diseases and Febrile Conditions. All patients underwent laboratory and serology testing, quantification of HBV DNA and HBs antigen (qHBsAg).

RESULTS:

A group of 56 patients were inactive carriers (IC), and 53 patients had HBeAg-negative CHB (AH). The mean values of ALT, HBV DNA and qHBsAg in IC were 29.13 U/L; 727.95 IU/ml and 2753.73 IU/ml respectively. In the AH group, the mean values of ALT, HBV DNA and quantitative HBsAg were 50.45 U/L; 7237363.98 IU/ml and 12556.06 IU/ml respectively. The serum value of ALT was more influenced by qHBsAg than HBV DNA in both IC and AH groups (R = 0.22 vs R = 0.15) (p > 0.05).

CONCLUSION:

patients with inactive and active HBeAg-negative CHB have similar laboratory and serology profile. It is necessary to combine analysis of ALT, HBV DNA and qHBsAg for better discrimination between patient’s IC and patient with HBeAg-negative CHB.

Non-invasive biomarkers for chronic hepatitis B virus infection management

Chronic hepatitis B virus (HBV) infection remains a major health burden with over 250 million cases worldwide. This complex infection can lead to chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. Complete recovery is seldom achieved due to the persistence in infected hepatocytes of covalently closed circular (ccc)DNA, which is not targeted by current antiviral therapies. Routine circulating biomarkers used for clinical monitoring of patients do not accurately reflect the cccDNA pool and transcriptional activity. New biomarkers, such as serum HB core-related Ag and circulating HBV RNAs, are under development. In this review, we discuss surrogate non-invasive biomarkers for evaluating intrahepatic cccDNA abundance and transcriptional activity. We also present their relevance for improving the classification of patients with regards to their natural history and for evaluating novel compounds to assess target engagement and to define new virological endpoints.

High risk of clinical events in untreated HBeAg-negative chronic hepatitis B patients with high viral load and no significant ALT elevation

BACKGROUND

It remains unknown whether antiviral treatment for HBeAg-negative chronic hepatitis B (CHB) patients having high viral loads without significant elevation of alanine aminotransferase (ALT) levels would reduce the risks of clinical events.

AIM

To compare clinical outcomes of high viral load CHB patients untreated for normal or mildly elevated ALT vs those treated for ALT ≥ 2 upper limit of normal (ULN).

METHODS

This historical cohort study included 5414 HBeAg-negative CHB patients without cirrhosis at a tertiary hospital in Korea from 2000 to 2013. Inactive phase was defined as serum hepatitis B virus [HBV] DNA < 2000 IU/mL and persistently normal ALT (n = 3572). High viral load (HBV DNA ≥ 2000 IU/mL) patients were classified into three phases by ALT levels: Replicative (persistently normal ALT, n = 900); Mildly active (ALT 1-2ULN, n = 396); and Active (ALT ≥ 2ULN, n = 546) phases. All Active phase patients were treated with nucleos(t)ide analogues.

RESULTS

The mean age of the patients was 47 years without a significant difference among the groups. Compared with the treated Active phase group, the untreated Replicative phase group showed a significantly higher risk of hepatocellular carcinoma (HCC; HR 1.76; 95% CI 1.00 - 3.10, P = 0.05) and death/transplantation (HR 2.14; 5% CI 1.09 - 4.21, P = 0.03) by propensity score-matched analysis. The untreated mildly active phase patients had further increase in risk of HCC and death/transplantation compared with the treated Active phase group by unadjusted, PS-matched, competing risks, and multivariable-adjusted analyses.

CONCLUSIONS

Untreated high viral load HBeAg-negative CHB patients without significant ALT elevation had higher risks of clinical events than treated Active phase patients with elevated ALT.

Baseline HBsAg levels associated with HBsAg loss in HBeAg-negative chronic hepatitis B infection with persistently normal alanine aminotransferase

BACKGROUND

We aimed to assess the long-term outcomes of e antigen-negative chronic hepatitis B (CHB) infection with low hepatitis B virus (HBV) DNA level (< 200 IU/mL) and persistently normal alanine aminotransferase (PNALT) and to explore the factors associated with the results.

METHODS

This retrospective cohort study enrolled consecutive baseline CHB patients with PNALT from January 2005 to June 2008. In total, 252 e antigen-negative CHB patients with PNALT and low HBV DNA level (< 200 IU/mL) were enrolled, of whom 188 were eligible for this analysis. Among the 188 patients, 131 were followed up more than twice per year and 57 were followed up at least once per year, with a median follow-up period of 102 (73-123) months.

RESULTS

Of 188 patients, 16 had HBV DNA level of > 200 IU/mL and PNALT, 164 had HBV DNA level of < 200 IU/mL and PNALT and 8 had HBV DNA level of > 200 IU/mL and elevated ALT level, of which 3 used an antiviral drug during follow-up. Twelve of 164 experienced HBsAg loss. Cox regression analysis suggested that baseline HBsAg levels were associated with HBsAg loss in patients after follow-up, especially the baseline HBsAg levels of < 200 IU⁄mL, which is a risk factor for HBsAg loss. The AUC of baseline HbsAg level in the e antigen-negative CHB group was 0.772 (cutoff value 426, P < 0.001). The cumulative probability of HBsAg loss in the HBsAg < 400 IU/L group was 20% (7/35), which ws higher than that in the HBsAg ≥ 400 IU/L group (3.88%; 5/129; X2 = 11.75, P = 0.0006).

CONCLUSION

The e antigen-negative CHB infection with low HBV DNA level (< 200 IU/mL) and PNALT will progress to chronic hepatitis, although the probability of its occurrence is low. Spontaneous HBsAg loss may not occur frequently because the manifested cumulative probability of HBsAg loss was higher in the HBsAg < 400 IU/L group than in the HBsAg ≥ 400 IU/L group.

Pregenomic RNA: How to assist the management of chronic hepatitis B?

Pregenomic RNA (pgRNA) is an emerging serological marker for chronic hepatitis B virus (HBV) infection. While pgRNA is principally the template for viral proteins and viral DNAs, additional novel functions for the serum pgRNA have recently been described. These results extend for pgRNA a regulatory function in the viral life cycle and potentially a role in pathogenesis. Here, we review the diverse roles of pgRNA in HBV replication and pathogenesis, emphasizing how the unique structure of this RNA is key to its various functions. We focus in particular on the role of HBV pgRNA in guiding antiviral therapy including nucleot(s)ide analog interruption and role as a marker of cure with new curative therapies. We also briefly allude to the emerging niche for new direct-acting or indirect-acting antivirals targeting pgRNA.

Serum hepatitis B core-related antigen is an effective tool to categorize patients with HBeAg-negative chronic hepatitis B

The discrimination between active chronic hepatitis B (CHB) and the clinically quiescent infection (CIB) is not always easy, as a significant portion of patients falls in a "grey" zone. Hepatitis B core-related antigen (HBcrAg) is a now quantifiable serological marker with potential applications in diagnosis and therapy monitoring. The aim of the present study was to evaluate the HBcrAg serum levels in HBeAg-negative HBV infection, and its ability in identifying the clinical profile, in comparison with HBsAg serum levels. HBcrAg was retrospectively assessed on serum samples from a population of treatment-naive HBeAg-negative patients by ChemiLuminescent Enzyme Immunoassay (CLEIA). HBsAg and HBV-DNA data were collected. Serological data were associated to clinical profile, defined in the subsequent follow-up of at least 1 year. In the overall population of 160 HBeAg-negative patients, HBcrAg results weakly correlated with qHBsAg levels (Spearman r = 0.471, P < 0.0001) and correlated closely with HBV-DNA (Spearman r = 0.746, P < 0.0001). HBcrAg levels were significantly higher in 85 CHB patients relative to 75 CIB carriers. A value of 2.5 logU/mL produced the optimal cut-off to identify CIB patients, with diagnostic accuracy comparable to HBsAg levels. In long-term clinical evaluation, a single measurement of HBcrAg at the established cut-off was optimally consistent with clinical outcome. Conversely, the HBsAg cut-off performed well in the true quiescent phase and less in more difficult-to-categorize patients. In conclusion, single-point use of HBcrAg serum levels provides an accurate identification of CIB and represents a useful tool for patient classification.

Serum hepatitis B core-related antigen (HBcrAg) correlates with covalently closed circular DNA transcriptional activity in chronic hepatitis B patients

BACKGROUND & AIMS

It has been proposed that serum hepatitis B core-related antigen (HBcrAg) reflects intrahepatic covalently closed circular (ccc)DNA levels. However, the correlation of HBcrAg with serum and intrahepatic viral markers and liver histology has not been comprehensively investigated in a large sample. We aimed to determine if HBcrAg could be a useful therapeutic marker in patients with chronic hepatitis B.

METHODS

HBcrAg was measured by chemiluminescent enzyme immunoassay in 130 (36 hepatitis B e antigen [HBeAg]+ and 94 HBeAg-) biopsy proven, untreated, patients with chronic hepatitis B. HBcrAg levels were correlated with: a) serum hepatitis B virus (HBV)-DNA, quantitative hepatitis B surface antigen and alanine aminotransferase levels; b) intrahepatic total (t)HBV-DNA, cccDNA, pregenomic (pg)RNA and cccDNA transcriptional activity (defined as pgRNA/cccDNA ratio); c) fibrosis and necroinflammatory activity scores.

RESULTS

HBcrAg levels were significantly higher in HBeAg+ vs. HBeAg- patients and correlated with serum HBV-DNA, intrahepatic tHBV-DNA, pgRNA and cccDNA levels, and transcriptional activity. Patients who were negative for HBcrAg (<3 LogU/ml) had less liver cccDNA and lower cccDNA activity than the HBcrAg+ group. Principal component analysis coupled with unsupervised clustering identified that in a subgroup of HBeAg- patients, higher HBcrAg levels were associated with higher serum HBV-DNA, intrahepatic tHBV-DNA, pgRNA, cccDNA transcriptional activity and with higher fibrosis and necroinflammatory activity scores.

CONCLUSIONS

Our results indicate that HBcrAg is a surrogate marker of both intrahepatic cccDNA and its transcriptional activity. HBcrAg could be useful in the evaluation of new antiviral therapies aiming at a functional cure of HBV infection either by directly or indirectly targeting the intrahepatic cccDNA pool.

LAY SUMMARY

Hepatitis B virus causes a chronic infection which develops into severe liver disease and liver cancer. The viral covalently closed circular DNA (cccDNA) is responsible for the persistence of the infection in hepatocytes. To better manage patient treatment and follow-up, and to develop new antiviral treatments directly targeting the intrahepatic pool of cccDNA, serum surrogate markers reflecting the viral activity in the liver are urgently needed. In this work, we demonstrate that quantification of hepatitis B core-related antigen in serum correlates with cccDNA amount and activity and could be used to monitor disease progression.

Serum Hepatitis B Virus RNA: A New Potential Biomarker for Chronic Hepatitis B Virus Infection

Chronic hepatitis B infection is one of the major etiological causes of liver failure, cirrhosis, and hepatocellular carcinoma (HCC) worldwide. This condition cannot be completely cured by currently available drugs due to the persistent existence of hepatitis B virus (HBV) covalently closed circular DNA (cccDNA), the bona fide transcription template for HBV RNAs, in infected hepatocytes. Because quantifying cccDNA per se requires an invasive procedure, serum biomarkers reflecting intrahepatic cccDNA activity are warranted. Recently, a growing body of research suggests that the circulating HBV RNA may serve as a serum biomarker for HBV infection, treatment, and prognosis. In order to delineate the molecular and clinical characteristics of serum HBV RNA, we systematically reviewed the available literature on serum HBV RNA dating back to the early 1990s. In this review, we summarize the reported serum HBV RNA quantification methods and discuss the potential HBV RNA species in patient serum. We also compare the reported correlations of serum HBV RNA with other serological markers, including HBV DNA, hepatitis B surface antigen, e antigen, and core-related antigen, as well as their correlations with intrahepatic cccDNA, to assess their potential in clinical applications. Future directions for serum HBV RNA research are also discussed.

Variants of hepatitis B virus surface antigen observed during therapy with nucleic acid polymer REP 2139-Ca have no influence on treatment outcome and its detection by diagnostic assays

The treatment of patients suffering from HBeAg-positive chronic hepatitis B with REP 2139-Ca resulted in potent reductions in HBsAg and HBV DNA, seroconversion to anti-HBs and the establishment of functional control of infection. In this cohort of 12 patients, we investigated whether differences between HBsAg sequences might explain the lack of response to REP 2139-Ca observed in 3 of 12 patients. We also assessed if the reduction or complete loss of HBsAg in serum observed during therapy were caused by mutations in the "a" determinant preventing the detection of HBsAg by standard diagnostic assays. The complete pre-S/S open reading frame (ORF) was sequenced and pre-S1, pre-S2 and S amino acid sequences were analysed. We found no major differences between pre-S1, pre-S2 and S sequences in responders and nonresponders correlated with low reduction in HBsAg. In addition, we found no mutations in the "a" determinant that would significantly affect the reactivity of HBsAg in diagnostic assays. These results demonstrate that the amino acid sequence of complete pre-S/S ORF has no direct influence on response to REP 2139-Ca therapy.

Okuda lecture: Challenges of hepatitis B in the era of antiviral therapy

Nucleos(t)ide analogs (NAs) are effective, safe, and convenient antiviral therapy to suppress replication of hepatitis B virus, which can be translated into improved long-term outcome of chronic hepatitis B patients. The current recommended first-line NAs, namely, entecavir and tenofovir, are largely free from problems of drug resistance. Nonetheless, there are still a few challenges in the era of NA. First, the risk of hepatocellular carcinoma can only be reduced but not eliminated, particularly among cirrhotic patients. For cirrhotic patients who have persistent low-level viremia on NA, that is, partial responders, the risk of hepatocellular carcinoma is higher than those with complete viral suppression. The best strategy to manage partial responders to entecavir or tenofovir is uncertain. Second, immune-tolerant patients are very difficult to treat with NA. A significant proportion of immune-tolerant patients will have detectable viremia despite a few years of continuous NA treatment, and the rate of hepatitis B e-antigen seroconversion is very low. Third, most patients need long-term treatment as NA cannot eliminate covalently closed circular DNA in the hepatocytes. Some patients can consider stop NA according to treatment guidelines, but viral and clinical relapses often occur after treatment cessation. There is no concrete consensus on when one should stop NA in a hepatitis B e-antigen-negative patient among different treatment guidelines. New biomarkers such as hepatitis B surface antigen level can be used to select patients to stop NA, but the data are still preliminary.

Automated Diagnosis of Hepatitis B Using Multilayer Mamdani Fuzzy Inference System

In this research, a new multilayered mamdani fuzzy inference system (Ml-MFIS) is proposed to diagnose hepatitis B. The proposed automated diagnosis of hepatitis B using multilayer mamdani fuzzy inference system (ADHB-ML-MFIS) expert system can classify the different stages of hepatitis B such as no hepatitis, acute HBV, or chronic HBV. The expert system has two input variables at layer I and seven input variables at layer II. At layer I, input variables are ALT and AST that detect the output condition of the liver to be normal or to have hepatitis or infection and/or other problems. The further input variables at layer II are HBsAg, anti-HBsAg, anti-HBcAg, anti-HBcAg-IgM, HBeAg, anti-HBeAg, and HBV-DNA that determine the output condition of hepatitis such as no hepatitis, acute hepatitis, or chronic hepatitis and other reasons that arise due to enzyme vaccination or due to previous hepatitis infection. This paper presents an analysis of the results accurately using the proposed ADHB-ML-MFIS expert system to model the complex hepatitis B processes with the medical expert opinion that is collected from the Pathology Department of Shalamar Hospital, Lahore, Pakistan. The overall accuracy of the proposed ADHB-ML-MFIS expert system is 92.2%.

Effect of hepatitis B virus (HBV) surface-gene variability on markers of replication during treated human immunodeficiency virus-HBV infection in Western Africa

BACKGROUND & AIMS

Replication markers exhibit substantial variation during chronic hepatitis B virus (HBV) infection, part of which can be explained by mutations on the surface (S) gene. We aimed to identify S-gene mutations possibly influencing the quantification of HBV replication markers (MUPIQH) in HBV genotype E infection, common to Western Africa.

METHODS

Seventy-three antiretroviral treatment (ART)-naïve human immunodeficiency virus (HIV)-HBV co-infected patients from Côte d'Ivoire, initiating anti-HBV-containing ART, had available HBV S-gene sequences. S-gene MUPIQHs were screened at ART initiation based on lower HBV-DNA or HBsAg quantification (qHBsAg) compared to wildtype. Their association with HBV virological response and qHBsAg slope during treatment was evaluated.

RESULTS

Genotype E was predominant (95.9%). At ART initiation, median HBV-DNA was 7.27 log₁₀ copies/mL (IQR = 5.26-8.33) and qHBsAg 4.08 log₁₀ IU/mL (IQR = 3.49-4.61). Twelve S-gene MUPIQHs were identified among 21 patients (28.8%): sS140L (n = 4), sD144A (n = 1), sS167L (n = 2), sS174N (n = 6), sP178Q (n = 2), sG185L (n = 2), sW191L (n = 2), sP203Q/R (n = 2), sS204N/I/R/K/T/G (n = 7), sN207T (n = 2), sF212C (n = 1) and sV224A/Y (n = 7). MUPIQHs at positions s185+s191+s224 and s178+s204 were within highly covarying networks of S-gene mutations. Older age (P = 0.02), elevated transaminases (P = 0.03) and anti-hepatitis B "e" antibody-positive serology (P = 0.009) were significantly associated with prevalent MUPIQHs at ART initiation. During treatment, baseline MUPIQHs were not associated with time-to-undetectable HBV-DNA (P = 0.7) and qHBsAg levels decreased at similar rates between those with vs without MUPIQHs (P = 0.5).

CONCLUSION

Several novel S-gene mutations were associated with reductions in replication markers among West African co-infected patients. These mutations, however, do not affect response during antiviral treatment. Their diagnostic and clinical consequences need clarification.

Hepatitis B Treatment: What We Know Now and What Remains to Be Researched

Chronic hepatitis B virus (HBV) infection remains a major global health burden. Currently, two types of treatment, interferons (IFNs) and nucleos(t)ide analogues (NAs), have been approved. These treatments are effective in suppressing HBV replication and in decreasing the risk of developing cirrhosis, liver failure, hepatocellular carcinoma (HCC), and death. However, these treatments do not eliminate the virus, and the risk of HCC remains. This review article summarizes current knowledge about the safety, efficacy, and clinical indications of hepatitis B treatment. It also discusses limitations of existing treatment, gaps in knowledge, and feasibility of a hepatitis B cure.

New and Old Biomarkers for Diagnosis and Management of Chronic Hepatitis B Virus Infection

Tests to detect the presence and activity of hepatitis B virus (HBV) are the cornerstones of diagnosis and management. Assays that detect or measure serum levels of HB surface antigen, HB surface antibody, and HB core antibody are used to identify patients with exposure to HBV, whereas other tests provide information on the level of virus replication, presence of specific variants, and presence of virus reservoirs. Newer diagnostic tests, used only in research settings so far, aim to quantify levels of intrahepatic HBV replication. Other tests have been developed to detect HBV infection in resource-limited settings. We review point-of-care tests (essential in global screening efforts), standard diagnostic tests used in routine clinical management, and newer tests that might be used in clinical trials of agents designed to cure HBV infection.

Switching to peginterferon for chronic hepatitis B patients with hepatitis B e antigen seroconversion on entecavir - A prospective study

Nucleos(t)ide analogues (NA) are effective in suppressing hepatitis B virus (HBV) replication, but most patients require long-term treatment. This study aimed to investigate switching to peginterferon as a strategy to stop NA. Hepatitis B e antigen (HBeAg)-positive chronic hepatitis B patients who developed HBeAg seroconversion during NA treatment were studied. All patients received open-label peginterferon alfa-2a 180 μg/wk for 48 weeks, and NA was stopped at week 4 of peginterferon treatment. The primary endpoint was sustained response, which was defined as negative HBeAg, positive anti-HBe and HBV DNA <2000 IU/mL at week 72. Other secondary endpoints including HBsAg loss at week 72 were also studied. Forty-one patients treated with entecavir for 56 ± 23 months were recruited. Sustained response was achieved in 30 patients (73%, 95% confidence interval 58%-84%). At week 72, 31 (76%) patients had HBeAg seroconversion, 56 (23%) patients had undetectable HBV DNA, 31 (76%) patients had normal ALT, and 6 patients (15%) had HBsAg loss. Baseline HBsAg level was the best predictor for both sustained response and HBsAg loss; the best HBsAg cut-off for sustained response was <1500 IU/mL and that for HBsAg loss was <500 IU/mL by receiver operating characteristic curve analysis. Twenty-two of 25 (88%) patients with baseline HBsAg <1500 IU/mL had sustained response. Five of 10 (50%) patients with baseline HBsAg <500 IU/mL developed HBsAg loss. Switching to peginterferon can be considered as a treatment option in NA-treated patients with HBeAg seroconversion, particularly among those with lower HBsAg levels.

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.

Performance of Hepatitis B Core-Related Antigen Versus Hepatitis B Surface Antigen and Hepatitis B Virus DNA in Predicting HBeAg-positive and HBeAg-negative Chronic Hepatitis

BACKGROUND

We examined changes in hepatitis B core-related antigen (HBcrAg) during the four sequential phases of chronic hepatitis B virus (HBV) infection: hepatitis B e antigen (HBeAg)-positive chronic infection (EPCI) and hepatitis (EPCH), followed by HBeAg-negative chronic infection (ENCI) and hepatitis (ENCH). We compared the performance of serum HBcrAg, hepatitis B surface antigen (HBsAg), and HBV DNA in predicting EPCH and ENCH.

METHODS

We enrolled 492 consecutive patients: 49 with EPCI, 243 with EPCH, 101 with ENCI, and 99 with ENCH. HBcrAg was detected by chemiluminescent enzyme immunoassays. HBsAg and HBeAg were detected by chemiluminescent microparticle immunoassays. HBV DNA was detected by real-time PCR. Predictive performance of HBcrAg, HBsAg, and HBV DNA was evaluated using ROC curves.

RESULTS

Areas under ROC curves (AUCs) of HBcrAg, HBsAg, and HBV DNA for predicting EPCH were 0.738, 0.812, and 0.717, respectively; optimal cutoffs were ≤1.43×10⁵ kU/mL, ≤1.89×10⁴ IU/mL, and ≤3.97×10⁷ IU/mL, with sensitivities and specificities of 66.3% and 77.6%, 65.0% and 93.9%, and 60.5% and 79.6%, respectively. AUCs of HBcrAg, HBsAg, and HBV DNA for predicting ENCH were 0.887, 0.581, and 0.978, respectively; optimal cutoffs were >26.8 kU/mL, >2.29×10² IU/mL, and >8.75×10³ IU/mL, with sensitivities and specificities of 72.7% and 95.1%, 86.9% and 39.6%, and 89.9% and 92.1%, respectively.

CONCLUSIONS

HBsAg and HBV DNA were the best predictors of EPCH and ENCH, respectively. HBcrAg is an important surrogate marker for predicting EPCH and ENCH.

Application strategies of serum HBV DNA detection in HBV infection patients: A retrospective study of 5611 specimens

The detection of hepatitis B virus (HBV) DNA plays a critical role in determining the level of viral replication in HBV-infected patients. However, how to select appropriate HBV DNA detection method, low-sensitivity (ls) and hypersensitivity (hs) remains unclear. In this study, hepatitis B surface antigen (HBsAg), hepatitis B e-antigen (HBeAg), alanine transaminase (ALT), aspartate transaminase (AST), and hs HBV DNA titers in serum of 5611 cases with suspected HBV infection were reviewed. Besides, the dynamic changes of HBV DNA and HBsAg in 85 chronic hepatitis B (CHB) patients receiving peginterferon α (PegIFNα) or entecavir (ETV) were observed. The results showed the positive rate of HBV DNA was 32.8%, of which low viral load (20 to 500 IU/mL) accounted for 51.8%. In the 5611 cases, when the HBsAg was less than 1000 IU/mL, the proportion of low viral load was 76.3%. Moreover, in patients receiving antiviral treatment, when HBsAg was less than 2000 IU/mL (PegIFNα) or HBsAg was less than 3500 IU/mL (ETV), the proportion of patients with low viral load was 79.5% or 78.0%, respectively. We developed a strategy of serum HBV DNA detection in HBV-infected patients. When HBsAg was negative, HBV DNA detection should be unnecessary. When HBsAg was 0.05 to 1000 IU/mL, hs HBV DNA should be detected in patients with abnormal level of ALT, AST, or HBeAg. While HBsAg was greater than or equal to 1000 IU/mL, ls HBV DNA was recommended. Moreover, the cutoff value of HBsAg increased during antiviral therapy of CHB patients. In conclusion, hs HBV DNA is of great value in HBV-infected patients with low viral load. HBV DNA detection methods should be selected reasonably according to the levels of HBsAg, HBeAg, ALT, and AST.

New viral biomarkers for Hepatitis B: Are we able to change practice?

The management of chronic hepatitis B virus (HBV) infection is challenged by its varying natural course and its stealthy nature. Not all HBV-infected patients will develop complications of infection; however, it is of utmost importance to identify patients who are at risk and require antiviral treatment and/or close surveillance. Hepatic inflammation and quantification of HBV DNA have guided treatment decisions in the last decade, and these guided interventions have been shown to reduce liver-related complications and death. Data on the quantification of additional HBV markers such as hepatitis B surface antigen (HBsAg), hepatitis B core-related antigen (HBcrAg) and hepatitis B virus RNA (HBV RNA) have accumulated in recent years. Here, we review the current evidence of how to use these markers and discuss open issues that require additional research.

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.