The updated EASL Clinical Practice Guidelines on the management of hepatitis B virus (HBV) infection provide comprehensive, evidence-based recommendations for its management. Spanning ten thematic sections, the guidelines address diagnostics, treatment goals, treatment indications, therapeutic options, hepatocellular carcinoma surveillance, management of special populations, HBV reactivation prophylaxis, post-transplant care, HBV prevention strategies, and finally address open questions and future research directions. Chronic HBV remains a global health challenge, with over 250 million individuals affected and significant mortality due to cirrhosis and hepatocellular carcinoma. These guidelines emphasise the importance of early diagnosis, risk stratification based on viral and host factors, and tailored antiviral therapy. Attention is given to simplified algorithms, vaccination, and screening to support global HBV elimination targets. The guidelines also discuss emerging biomarkers and evolving definitions of functional and partial cure. Developed through literature review, expert consensus, and a Delphi process, the guidelines aim to equip healthcare providers across disciplines with practical tools to optimise HBV care and outcomes worldwide.

The Hepatitis B Virus (HBV) presents a formidable global health challenge, impacting hundreds of millions worldwide and imposing a considerable burden on healthcare systems. The elusive nature of the virus, with its ability to establish chronic infection and evade immune detection, and the absence of curative agents have prompted efforts to develop novel therapeutic approaches beyond current antiviral treatments. This review addresses the challenging concept of a functional cure for HBV, a state characterized by the suppression of HBV and HBsAg, mitigating disease progression and transmission without a complete cure. We provide an overview of HBV epidemiology and its clinical impact, followed by an exploration of the current treatment landscape and its limitations. The immunological basis of a functional cure is then discussed, exploring the intricate interplay between the virus and the host immune response. Emerging therapeutic approaches, such as RNA interference-based interventions, entry inhibitors, nucleic acid polymers, and therapeutic vaccines, are discussed with regard to their success in achieving a functional cure. Lastly, the review underscores the urgent need for innovative strategies to achieve a functional cure for HBV.

Hepatitis B virus (HBV) is a global health problem with over 250 million people affected worldwide. Nucleos(t)ide analogues remain the standard of care and suppress production of progeny virions; however, they have limited effect on the viral transcriptome and long-term treatment is associated with off-target toxicities. Promising results are emerging from clinical trials and several drug classes have been evaluated, including capsid assembly modulators and RNA interfering agents. Whilst peripheral biomarkers are used to monitor responses and define treatment endpoints, they fail to reflect the full reservoir of infected hepatocytes. Given these limitations, consideration should be given to the merits of sampling liver tissue, especially in the context of clinical trials. In this review article, we will discuss methods for profiling HBV in liver tissue and their value to the HBV cure programme.

Loss of hepatitis B surface antigen (HBsAg) is the pivotal component of functional cure in patients suffering from chronic hepatitis B (CHB). The predictive value of quantitative HBsAg (qHBsAg) in HBsAg loss among those undergoing nucleos(t)ide analog (NAs) therapy is an area of ongoing investigation.

A retrospective cohort study using electronic medical records was performed. CHB patients with NAs treatment between January 1, 2012, and December 31, 2020 were enrolled and followed up until discontinuation of NAs, as indicated by a gap more than 12 months in prescription refills, past medical record, or study end. Patients were grouped into NAs treatment-naïve cohort and treatment-experienced cohort. In both cohorts, Cox regression models assessed associations between 12-month reduction in qHBsAg, baseline qHBsAg, and HBsAg loss.

Overall, 2,627 CHB patients with NAs treatment was identified, including 1,179 in treatment-naïve cohort and 1,448 in treatment-experienced cohort. In treatment-naïve cohort, 9 patients had HBsAg loss (0.51/100 person-years). In treatment-experienced cohort, 30 patients had HBsAg loss (1.03/100 person-years). HBsAg loss was significantly associated with a 0.5-1 log10 (treatment-naïve: adjusted hazard ratio [aHR] 8.06, 95% confidence interval [CI] 1.29-50.40; treatment-experienced: aHR 4.34, 95% CI 1.40-13.47) and >1 log10 qHBsAg decrease (treatment-naïve: aHR 9.19, 95% CI 1.47-57.65; treatment-experienced: aHR 8.02, 95% CI 1.76-36.57) compared with qHBsAg not reduced. HBsAg loss was significantly associated with lower baseline qHBsAg in treatment-experienced cohort, while such difference was not significant in treatment-naïve cohort.

A rapid decline of qHBsAg in 12 months during NAs therapy, as opposed to merely maintaining a low level of qHBsAg, was associated with HBsAg loss.

Identifying hepatitis B virus (HBV) patients eligible for safe nucleos(t)ide analogues (NAs) discontinuation remains challenging. Discrepant data on combined HBV DNA and quantitative HBV surface antigen (qHBsAg) assessments are available. This study aimed to identify potential predictors for safe treatment discontinuation by evaluating clinical/virological outcomes in patients on long-term NA therapy.

A retrospective cohort of 139 chronic hepatitis B (CHB) patients - who consecutively started Entecavir or Tenofovir from 2007 to 2011 - was evaluated. The study population was selected based on anti-HBe positivity, absence of prior antiviral treatment, absence of non-HBV-related liver diseases or hepatocellular carcinoma (HCC), and long-term clinical/ultrasonographic/laboratory evaluations post-NA initiation. Serum samples collected before starting NA (T0) and over ten years (T1-T10) were tested for HBV DNA and qHBsAg.

Twenty-two/139 (15.8 %) CHB patients (12 chronic hepatitis, 10 cirrhosis) met the inclusion criteria. All patients showed a significant decrease in liver stiffness values in the ten years of follow-up (p = 0.001), and no hepatic decompensation occurred. Three/22 (13.6 %) patients developed HCC. Ten/22 patients (45.5 %; group-A) had fluctuating HBV DNA, while other 10/22 (45.5 %; group-B) showed undetectable HBV DNA for 5-9 years with more significant qHBsAg decline (p = 0.04) than group-A. Two/22 (9.1 %) patients showed a critical qHBsAg decline up to seroconversion together with undetectable HBV DNA.

Persistent undetectable HBV DNA levels correlate with qHBsAg reduction and the potential HBsAg seroclearance, suggesting that long-term HBV DNA monitoring in NA-treated CHB patients might help identify candidates for treatment discontinuation.

A functional cure is an essential endpoint in the management of patients with chronic hepatitis B virus (HBV) infection. We evaluated the cumulative probability and predictors of functional cure in patients with chronic HBV infection after hepatitis B e antigen (HBeAg) seroconversion.

We retrospectively analyzed 413 (249 males and 164 females) initially HBeAg-positive chronic HBV-infected patients who were followed up for a mean of 26.36 ± 0.53 years. All underwent HBeAg seroconversion during follow-up. A functional cure was defined as durable HBsAg and HBV DNA loss without antiviral treatment for more than 24 weeks.

After 10,888 person-years of follow-up, the cumulative probability of functional cure was 14.53% (n = 60). There were 24 (40%) subjects with functional cure after antiviral therapy. The annual functional cure rate was 0.55% per person-year, and increased to 0.96% per person-year after HBeAg seroconversion. In subjects with functional cure, the HBsAg and HBV DNA titers after HBeAg seroconversion were positively correlated with the time to functional cure (P < .001 and < .001, respectively). Multivariate Cox proportional hazards analysis of the cohort revealed that HBeAg seroconversion at <18 years of age, high-genetic-barrier nucleos(t)ide analogue(s) therapy before HBeAg seroconversion, and a serum HBsAg titer <1000 IU/mL at 18 months after HBeAg seroconversion were significant predictors of functional cure (P < .001, .001, and .001, respectively).

In a cohort of chronic HBV-infected patients with long-term follow-up, HBeAg seroconversion in childhood, high-genetic-barrier nucleos(t)ide analogue(s) therapy, and low HBsAg titers after HBeAg seroconversion were significant predictors of functional cure.

Changes in serum hepatitis B surface antigen (HBsAg) during treatment are associated with HBsAg loss. However, little is known about the trajectory patterns of HBsAg in early treatment and their relationship to subsequent HBsAg loss.

A retrospective study was conducted on 166 treatment-naive children with hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB). Latent class trajectory analysis was used to identify trajectory groups of serum HBsAg. Cox proportional hazards models were used to assess the association between HBsAg trajectory groups and HBsAg loss.

The median follow-up time was 20.70 (interquartile range, 12.54-34.17) months, and HBsAg loss occurred in 70 (42.17%) of all study participants. Using latent class trajectory analysis, HBeAg-positive patients with CHB were classified into 3 trajectory groups: trajectory 1 (sustained stability, 24.70%), trajectory 2 (slow decline, 38.55%), and trajectory 3 (rapid decline, 36.75%), respectively. The risk of achieving HBsAg loss was higher in both trajectory 2 (hazard ratio, 3.65 [95% confidence interval, 1.70-7.83]) and trajectory 3 (7.27 [3.01-17.61]), respectively.

Serum HBsAg levels during early treatment can be classified into distinct trajectory groups, which may serve as an additional predictive indicator for HBsAg loss in HBeAg-positive children with CHB.

Recent evidence has indicated that the O-glycosylated PreS2 domain of the middle HBsAg is a distinguishing characteristic that allows the identification of HBsAg of HBV Dane particles and SVPs. This study's objective was to assess the changes in serum O-glycosylated HBsAg levels in CHB patients undergoing ETV or Peg-IFNα treatment.

Our retrospective study enrolled 86 patients with genotype C CHB. We determined the O-glycosylated HBsAg, HBsAg, HBeAg, HBV DNA, and HBV RNA at baseline and during ETV or Peg-IFNα treatment. The correlations between O-glycosylated HBsAg and conventional HBV marker levels were also examined. Furthermore, we performed a ROC analysis to evaluate the predictive value of individual biomarkers for virological response.

At baseline, the serum O-glycosylated HBsAg levels were significantly correlated with the HBsAg (r = 0.754), HBV DNA (r = 0.498), HBeAg (r = 0.404), and HBV RNA (r = 0.399) in HBeAg positive patients. O-glycosylated HBsAg decreased after antiviral therapy. Both O-glycosylated HBsAg and HBsAg were significantly correlated with serum HBV DNA as well as HBV RNA at baseline, while only O-glycosylated HBsAg still correlated with HBV RNA (r = 0.397) in DNA-undetectable patients after ETV therapy. O-glycosylated HBsAg was significantly correlated with HBV RNA (r = 0.846) in DNA-undetectable patients after Peg-IFNα therapy compared to that of HBsAg (r = 0.800).

Serum O-glycosylated HBsAg level decreased during anti-viral therapy and correlated well with conventional HBV markers in HBeAg positive genotype C patients, suggesting that it could be a potential monitoring biomarker in HBV DNA-suppressed patients.

Prognostic factors for the long-term evolution of chronic hepatitis B e antigen (HBeAg)-negative hepatitis B virus (HBV) infection may vary depending on local epidemiology. We aimed to identify these factors in France, where the epidemiology is influenced by diverse immigration. Hepatitis B surface antigen (HBsAg)-positive, HBeAg-negative adults with normal transaminase levels and viral loads < 20,000 IU/mL for 1 year, without viral co-infection or advanced liver disease, were enrolled for a 5-year follow-up. A total of 564 patients were recruited from 23 centres (54.4% women, mean age 42.3 ± 12 years, 47.7% from sub-Saharan Africa). HBV DNA was detectable but < 2000 IU/mL for most (71.3%). Genotypes E (27.8%) and A (20.0%) were predominant. The mean HBsAg titre was 3.8 ± 3.4 log IU/mL, > 1000 IU/mL in 60% of cases, and higher in genotype E (p < 0.0001). During follow-up, 18 patients received antiviral treatment, 9 for viral reactivation (0.3% per year) and 9 preemptively. HBsAg loss occurred in 39 patients (1.4% per year). These patients were older (p < 0.0001), more frequently treated for dyslipidemia, hypertension or diabetes (p < 0.05), and had lower baseline HBV DNA (p = 0.0112) and HBsAg (p < 0.0001), but similar levels of HBcrAg compared to those who did not clear HBsAg. Baseline HBsAg was the only independent predictor of HBsAg loss (p = 0.009). In this cohort, HBsAg < 153 IU/mL predicted clearance with 87% sensitivity and specificity. In conclusion, baseline HBsAg accurately predicted seroclearance at 5 years in patients with chronic HBeAg-negative infection, regardless of genotype, sex, or geographical origin, indicating that this marker is widely applicable for reducing the frequency of patient monitoring.

The Hepatitis B surface antigen (HBsAg) as the only lipid-associated envelope protein of the Hepatitis B virus (HBV) acts as cellular attachment and entry mediator of HBV making it the main target of neutralizing antibodies to provide HBV immunity after infection or vaccination. Despite its central role in inducing protective immunity, there is however a surprising lack of comparative studies examining different HBsAgs and their ability to detect anti-HBs antibodies. On the contrary, various time-consuming complex HBsAg production protocols have been established, which result in structurally and functionally insufficiently characterized HBsAg. Here, we present an easy-to-perform, streamlined and robust method for recombinant S-HBsAg virus-like particle (VLP) production by transient expression in mammalian cells and purification from the cell lysate with the aim of displaying uniform antigenic epitopes on the surface to improve serological detection of anti-HBs antibodies. We not only compare assembly status and particle composition by transmission electron microscopy and mass photometry of our S-HBsAg and of commonly used HBsAg reference samples, but also assess their antigenic quality and functional suitability for anti-HBs antibody detection to identify the best performing sample for serological screenings. While we found that serum-isolated and recombinant HBsAg VLPs are assembled differently, our S-HBsAg VLPs detected anti-HBs antibodies with the highest sensitivity and specificity in multiplex serology when compared to yeast or serum HBsAg making it the most suitable antigen for analysis of HBV immunity through anti-HBs serostatus.

The induction of effective CD8+ T cells is thought to play a critical role in the functional cure of chronic hepatitis B (CHB). Additionally, the use of checkpoint inhibitors is being evaluated to overcome T-cell dysfunction during CHB.

A chimpanzee adenoviral vector (ChAdOx1-HBV) and a Modified vaccinia Ankara boost (MVA-HBV) encoding the inactivated polymerase, core, and S region from a consensus genotype C HBV were studied. Fifty-five patients with virally suppressed CHB and HBsAg <4,000 IU/ml were enrolled. Group 1 received MVA-HBV intramuscularly on Day 0 and 28, Group 2 received ChAdOx1-HBV on Day 0 and MVA-HBV on Day 28 (VTP-300), Group 3 received VTP-300 + low-dose nivolumab (LDN) on Day 28, and Group 4 received VTP-300 plus LDN with both injections.

VTP-300 alone and in combination with LDN was well tolerated with no treatment-related serious adverse events. Reductions of HBsAg were demonstrated in Group 2: 3 of 18 patients with starting HBsAg <50 IU/ml had durable log10 declines of >0.7 log10 at 2 months after the last dose. Group 3 (n = 18) had mean reductions in HBsAg of 0.76 log10 and 0.80 log10 (p <0.001) at 2 and 7 months after the last dose. Two patients developed persistent non-detectable HBsAg levels. CD4+ and CD8+ antigen-specific T-cell responses were generated and there was a correlation between IFN-γ ELISpot response and HBsAg decline in Group 2.

VTP-300 induced CD4+ and CD8+ T cells and lowered HBsAg in a subset of patients with baseline values below 100 IU/ml. The addition of LDN resulted in significant reduction in surface antigen. VTP-300 is a promising immunotherapeutic that warrants further development alone or in combination therapies.

The induction of potent, durable CD8+ T cells may be critical to achieving a functional cure in chronic HBV infection. A prime-boost immunotherapeutic consisting of an adenoviral-vector encoding hepatitis B antigens followed by a pox virus boost was shown to induce CD8+ T cells and to lower HBsAg, either alone or more impactfully when administered in conjunction with a checkpoint inhibitor, in patients with chronic hepatitis B. The use of immunotherapeutics in this setting warrants further evaluation.

NCT047789.

In patients who progress from acute hepatitis B virus (HBV) infection to a chronic HBV (CHB) infection, CD8+ T cells fail to eliminate the virus and become impaired. A functional cure of CHB likely requires CD8+ T cell responses different from those induced by the infection. Here we report preclinical immunogenicity and efficacy of an HBV therapeutic vaccine that includes herpes simplex virus (HSV) glycoprotein D (gD), a checkpoint modifier of early T cell activation, that augments CD8+ T cell responses. The vaccine is based on a chimpanzee adenovirus serotype 6 (AdC6) vector, called AdC6-gDHBV2, which targets conserved and highly immunogenic regions of the viral polymerase and core antigens fused to HSV gD. The vaccine was tested with and without gD in mice for immunogenicity, and in an AAV8-1.3HBV vector model of antiviral efficacy. The vaccine encoding the HBV antigens within gD stimulates potent and broad CD8+ T cell responses. In a surrogate model of HBV infection, a single intramuscular injection achieved pronounced and sustained declines of circulating HBV DNA copies and HBV surface antigen; both inversely correlated with HBV-specific CD8+ T cell frequencies in spleen and liver.

Chronic hepatitis B virus (HBV) infection is a global issue and can lead to cirrhosis and hepatocellular carcinoma (HCC). Hepatitis B surface antigen (HBsAg) is an important marker of HBV infection and HBsAg quantification could be a useful tool in clinical practice. This systematic literature review aimed to explore the association between HBsAg titres and long-term disease outcomes and evaluate the relationship between HBsAg titres, or changes in HBsAg titres, and clinical and treatment characteristics in patients with chronic HBV infection. Structured searches were performed in MEDLINE and Embase (January 2000 to 31 March 2023). Eighty-two studies were included, comprising 51% retrospective cohort studies, mostly conducted in Asia (85%). HBsAg levels were shown to predict the long-term development of cirrhosis and HCC in patients who were untreated prior to and during follow-up; however, these data were inconclusive in mixed and treated populations. HBsAg titres were significantly associated with various virological markers including serum HBV DNA, HBcrAg, HBeAg, HBV RNA levels, intrahepatic covalently closed circular DNA (cccDNA) and intrahepatic HBsAg expression. HBsAg titres generally declined over time; this decline was more pronounced in early (HBeAg-positive) than later disease phases (HBeAg-negative). Higher decline in HBsAg levels was consistently associated with subsequent HBsAg seroclearance and a greater decline in total intrahepatic HBV DNA and cccDNA levels. In conclusion, this review showed that HBsAg levels and rates of decline could inform assessment, management and prediction of outcomes in chronic HBV infection. Further studies in broader, more diverse populations and treated patients are needed.

Functional cure for chronic hepatitis B (CHB) requires finite treatment. Two agents under investigation with the goal of achieving functional cure are the small-interfering RNA JNJ-73763989 (JNJ-3989) and the capsid assembly modulator JNJ-56136379 (JNJ-6379; bersacapavir).

REEF-2, a phase IIb, double-blind, placebo-controlled, randomized study, enrolled 130 nucleos(t)ide analogue (NA)-suppressed hepatitis B e-antigen (HBeAg)-negative patients with CHB who received JNJ-3989 (200 mg subcutaneously every 4 weeks) + JNJ-6379 (250 mg oral daily) + NA (oral daily; active arm) or placebos for JNJ-3989 and JNJ-6379 +active NA (control arm) for 48 weeks followed by 48 weeks off-treatment follow-up.

At follow-up Week 24, no patients achieved the primary endpoint of functional cure (off-treatment hepatitis B surface antigen [HBsAg] seroclearance). No patients achieved functional cure at follow-up Week 48. There was a pronounced on-treatment reduction in mean HBsAg from baseline at Week 48 in the active arm vs. no decline in the control arm (1.89 vs. 0.06 log10 IU/ml; p = 0.001). At follow-up Week 48, reductions from baseline were >1 log10 IU/ml in 81.5% vs. 12.5% of patients in the active and control arms, respectively, and 38/81 (46.9%) patients in the active arm achieved HBsAg <100 IU/ml vs. 6/40 (15.0%) patients in the control arm. Off-treatment HBV DNA relapse and alanine aminotransferase increases were less frequent in the active arm, with 7/77 (9.1%) and 11/41 (26.8%) patients in the active and control arms, respectively, restarting NAs during follow-up.

Finite 48-week treatment with JNJ-3989 + JNJ-6379 + NA resulted in fewer and less severe post-treatment HBV DNA increases and alanine aminotransferase flares, and a higher proportion of patients with off-treatment HBV DNA suppression, with or without HBsAg suppression, but did not result in functional cure.

Achieving a functional cure from chronic hepatitis B (CHB) with finite treatments is a major unmet medical need. The current study assessed the rate of functional cure and clinical outcome after controlled nucleos(t)ide analogue (NA) withdrawal in patients with low levels of HBsAg induced by 48 weeks of treatment with the small-interfering RNA JNJ-3989 and the capsid assembly modulator JNJ-6379 plus NA vs. patients who only received NA treatment. Though functional cure was not achieved by any patient in either arm, the 48-week treatment regimen of JNJ-3989, JNJ-6379, and NA did result in more patients achieving pronounced reductions in HBsAg, with clinically meaningful reductions maintained for up to 48 weeks off all treatments, as well as fewer off-treatment HBV DNA increases and alanine aminotransferase flares. These findings provide valuable insights for future studies investigating potential finite treatment options, while the reported efficacy and safety outcomes may be of interest to healthcare providers making treatment decisions for patients with NA-suppressed HBeAg-negative CHB.

NCT04129554.

The detection of hepatitis B surface antigen (HBsAg) is critical in diagnosing hepatitis B virus (HBV) infection. However, existing clinical detection technologies inevitably cause certain inaccuracies, leading to delayed or unwarranted treatment. Here, we introduce a label-free plasmonic biosensing method based on the thickness-sensitive plasmonic coupling, combined with supervised deep learning (DL) using neural networks. The strategy of utilizing neural networks to process output data can reduce the limit of detection (LOD) of the sensor and significantly improve the accuracy (from 93.1%-97.4% to 99%-99.6%). Compared with widely used emerging clinical technologies, our platform achieves accurate decisions with higher sensitivity in a short assay time (∼30 min). The integration of DL models considerably simplifies the readout procedure, resulting in a substantial decrease in processing time. Our findings offer a promising avenue for developing high-precision molecular detection tools for point-of-care (POC) applications.

Hepatitis B surface antigen (HBsAg) is not only the biomarker of hepatitis B virus (HBV) infection and expression activity in hepatocytes, but it also contributes to viral specific T cell exhaustion and HBV persistent infection. Therefore, anti-HBV therapies targeting HBsAg to achieve HBsAg loss are key approaches for an HBV functional cure. In this study, we found that YZH-106, a rupestonic acid derivative, inhibited HBsAg secretion and viral replication. Further investigation demonstrated that YZH-106 promoted the lysosomal degradation of viral L- and M-HBs proteins. A mechanistic study using Biacore and docking analysis revealed that YZH-106 bound directly to the PreS2 domain of L- and M-HBsAg, thereby blocking their entry into the endoplasmic reticulum (ER) and promoting their degradation in cytoplasm. Our work thereby provides the basis for the design of a novel compound therapy to target HBsAg against HBV infection.

Viral hepatitis, caused by its etiology, hepatitis virus, is a public health problem globally. Among all infections caused by hepatitis-associated viruses, hepatitis B virus (HBV) infection remains the most serious medical concern. HBV infection particularly affects people in East Asia and Africa, the Mediterranean region, and Eastern Europe, with a prevalence rate of > 2%. Currently, approximately 1 billion people worldwide are infected with HBV, and nearly 30% of them experience chronic infection. Chronic HBV infection can lead to chronic hepatitis B (CHB), liver cirrhosis, and hepatocellular carcinoma (HCC), resulting in the related death of approximately 1 million people annually. Although preventative vaccines and antiviral therapies are currently available, there is no cure for this infection. Clinical testing is not only the gateway for diagnosis of HBV infection, but also crucial for judging the timing of medication, evaluating the effect of antiviral therapy, and predicting the risk of relapse after drug withdrawal in the whole follow-up management of hepatitis B infected persons. With advances in detection technology, it is now possible to measure various viral components in the blood to assess the clinical status of HBV infection. Serum viral products of HBV infection, such as HBV DNA, HBV RNA, hepatitis B surface antigen, hepatitis B e-antigen, and hepatitis B core-related antigen, are non-invasive indicators that are critical for the rapid diagnosis and management of related diseases. Improving the sensitivity of monitoring of these products is essential, and the development of corresponding detection technologies is pivotal in achieving this goal. This review aims to offer valuable insights into CHB infection and references for its effective treatment. We provide a comprehensive and systematic overview of classical and novel methods for detecting HBV serum viral products and discusses their clinical applications, along with the latest research progress in this field.

Nucleot(s)ide analogues, the current antiviral treatments against chronic hepatitis B (CHB) infection, are non-curative due to their inability to eliminate covalently closed circular DNA (cccDNA) from the infected hepatocytes. Preclinical studies have shown that coumarin derivatives can effectively reduce the HBV DNA replication. We evaluated the antiviral efficacy of thirty new coumarin derivatives in cell culture models for studying HBV. Furanocoumarins Fc-20 and Fc-31 suppressed the levels of pre-genomic RNA as well as cccDNA, and reduced the secretion of virions, HBsAg and HBeAg. The antiviral efficacies of Fc-20 and Fc31 improved further when used in combination with the hepatitis B antiviral drug Entecavir. There was a marked reduction in the intracellular HBx level in the presence of these furanocoumarins due to proteasomal degradation resulting in the down-regulation of HBx-dependent viral genes. Importantly, both Fc-20 and Fc-31 were non-cytotoxic to cells even at high concentrations. Further, our molecular docking studies confirmed a moderate to high affinity interaction between furanocoumarins and viral HBx via residues Ala3, Arg26 and Lys140. These data suggest that furanocoumarins could be developed as a new therapeutic for CHB infection.

Chronic Hepatitis B (CHB) remains a major public health problem, leading to various complications such as liver fibrosis, cirrhosis, and hepatocellular carcinoma. The existing diagnostic markers for Hepatitis B virus (HBV) are limited in distinguishing different CHB phases and intra-hepatic viral replication activity. In the past few years, several non-invasive potential blood markers that reflect viral intra-hepatic replicative state more accurately have been in progress and are gaining importance. Despite substantial efforts, the clinical utility of these new markers in CHB management is limited and unexplored. Therefore, in this review, we will discuss some of the newer HBV markers, their potential role in the diagnosis and monitoring of CHB patients.

Agarwal R, Gupta E, Samal J, et al. Newer Diagnostic Virological Markers for Hepatitis B Virus Infection. Euroasian J Hepato-Gastroenterol 2024;14(2):214-220.

Nanostructured metal oxides (NMOs) provide electrical properties such as high surface-to-volume ratio, reaction activity, and good adsorption strength. Furthermore, they serve as a conductive substrate for the immobilization of biomolecules, exhibiting notable biological activity. Capitalizing on these characteristics, they find utility in the development of various electrochemical biosensing devices, elevating the sensitivity and selectivity of such diagnostic platforms. In this review, different types of NMOs, including zinc oxide (ZnO), titanium dioxide (TiO2), iron (II, III) oxide (Fe3O4), nickel oxide (NiO), and copper oxide (CuO); their synthesis methods; and how they can be integrated into biosensors used for medical diagnosis are examined. It also includes a detailed table for the last 10 years covering the morphologies, analysis techniques, analytes, and analytical performances of electrochemical biosensors developed for medical diagnosis.

Quantitative fluorescence immunoassay is essential for the construction of biosensing mechanisms and the quantification of trace markers. But the interference problems caused by low fluorescence efficiency and broad fluorescence spectrum of fluorescent probes have hindered the continued development of ratiometric fluorescence sensing in biosensing. Perovskite materials, with ultra-high color purity (FWHM < 30 nm) and photoluminescence quantum yield (PLQY) (close to 100%), are expected to be next-generation fluorescent probes. However, poor water stability and biocompatibility are still non-negligible in biosensor applications. In this work, hyperstatic perovskite fluorescent microspheres prepared by swelling-shrinking method can be used as ratiometric fluorescence signals and biological immunoassay platforms. Meanwhile, inspired by p-aminophenol (AP) controlled synthesis and the catalytic reaction of 4-aminophenol phosphate (APP) triggered by alkaline phosphatase (ALP), a strategy to prepare fluorescent nanoparticles as fluorescence signals for ALP detection is proposed. Most importantly, it is proposed for the first time to combine this enzymatic fluorescence with perovskite materials using covalent linkage to create a novel cascade immunoassay and use it for quantitative and visualization determination of hepatitis B surface antigen (HBsAg) for application verification. These results indicate the biosensing potential of perovskite materials and provide a pathway for high sensitivity enzyme detection and enzyme triggered immune detection.

Despite the availability of vaccines, hepatitis B remains a significant cause of fulminant hepatitis, liver cirrhosis and hepatocellular carcinoma worldwide. The increase in reported hepatitis B cases in Germany is attributed to factors such as immigration and the hepatitis B surface antigen (HBsAg) screening introduced in 2020 as part of health check-ups. The indication for treatment depends on various factors, including the level of hepatitis B virus (HBV) DNA and inflammatory activity. Nucleos(t)ide analogues are the preferred treatment option, but functional cure, defined as HBsAg loss, is rare. In principle, treatment with nucleos(t)ide analogues should usually be discontinued after loss of HBsAg, but can be stopped earlier under certain conditions and is currently the subject of ongoing research. Pregnancy and immunosuppression in the context of hepatitis B require special attention. In addition, a possible hepatitis D virus co-infection must always be taken into account, which is why every HBsAg-positive person should be tested for anti-HDV. Since 2020, the entry inhibitor bulevirtide has become a new treatment option alongside pegylated interferon alfa, which represents a significant advance in the treatment landscape.

Reactivation of hepatitis B virus (HBV) infection is a well-known risk that can occur spontaneously or following immunosuppressive therapies, including cancer chemotherapy. HBV reactivation can cause significant morbidity and even mortality, which are preventable if at-risk individuals are identified through screening and started on antiviral prophylaxis.

To determine the prevalence of chronic HBV (CHB) and occult HBV infection (OBI) among oncology and hematology-oncology patients undergoing chemotherapy.

In this observational study, the prevalence of CHB and OBI was assessed among patients receiving chemotherapy. Serological markers of HBV infection [hepatitis B surface antigen (HBsAg)/anti-hepatitis B core antigen (HBc)] were evaluated for all patients. HBV DNA levels were assessed in those who tested negative for HBsAg but positive for total anti-HBc.

The prevalence of CHB in the study cohort was determined to be 2.3% [95% confidence interval (95%CI): 1.0-4.2]. Additionally, the prevalence of OBI among the study participants was found to be 0.8% (95%CI: 0.2-2.3).

The findings of this study highlight the importance of screening for hepatitis B infection in oncology and hematology-oncology patients undergoing chemotherapy. Identifying individuals with CHB and OBI is crucial for implementing appropriate antiviral prophylaxis to prevent the reactivation of HBV infection, which can lead to increased morbidity and mortality.

Hepatitis E virus (HEV) is a pathogen of global significance, but the value of HEV-related markers in the diagnosis of hepatitis E remains controversial. Previous studies on hepatitis E profiles have been mainly cross-sectional and conducted among inpatients in large hospitals, and hepatitis E cases have been primarily defined by limited partial markers. In this community-based study, 4,110 active hepatitis cases from a population of nearly 600,000 were followed over 48 months and serial serum samples were collected. Both HEV pathogen (HEV RNA and antigen) and anti-HEV antibody markers were used to determine HEV infection status and the relationship between hepatitis and HEV infection. In total, 98 hepatitis E patients were identified and all available isolates from 58 patients belonged to HEV genotype 4. The mean age of the patients was 58.14 years, with an overwhelming proportion of males (70.4%). Hepatitis E accounted for 22.86% of active hepatitis cases with alanine aminotransferase levels ≥15.0-fold the upper limit of normal, suggesting the need to include HEV in routine testing for these patients. Ninety-two hepatitis E patients were positive for at least 2 of HEV antigen, anti-HEV IgM, and HEV RNA markers at presentation, and 90.22% of them were positive for HEV antigen and anti-HEV IgM. HEV antigen, HEV RNA, and anti-HEV IgM positivity were observed in 89.80%, 82.65%, and 93.88% of hepatitis E patients at presentation, respectively. However, only 57.14% of anti-HEV IgM positivity occurred in hepatitis E patients. These findings will advance our understanding of hepatitis E and improve diagnosis.

The purpose of this study was to develop an effective and non-invasive nomogram for evaluating liver obvious inflammation in untreated HBeAg positive patients with chronic hepatitis B virus (HBV) infection. A nomogram was established on a model cohort of 292 treatment-naïve HBeAg positive patients with normal alanine aminotransferase (ALT ≤40 U/L) at Beijing Ditan Hospital from January 2008 to March 2018. Then the nomogram was prospectively validated in a cohort of 88 patients from July 2019 to May 2021. Calibration curves and Concordance index were used to evaluate the accuracy of prediction and identification performance of the model. In untreated HBeAg positive chronic hepatitis B virus infection patients with normal ALT, the formula for predicting liver inflammation was Logit (P) =-0.91-0.41×log10 (qHBeAg)+0.11×AST-0.01×PLT. The nomogram had C-index of 0.751 (95% CI, 0.688-0.815), indicating a good consistency between prediction and real observation on the model cohort. The validation cohort confirmed its good performance. In this study, liver inflammation nomograms based on HBeAg, AST, and PLT were established and verified in treatment-naïve HBeAg positive chronic HBV patients with normal ALT.

Indices for predicting HBsAg or HBeAg seroconversion in patients with chronic hepatitis B virus (HBV) infection during antiviral therapy remain elusive. We aimed to investigate if the presence of HBsAb-specific B cells at baseline can predict HBsAg or HBeAg seroconversion. In this study, 134 treatment-naive patients with chronic HBV were enrolled. A baseline HBsAb-specific B cell ELISpot assay was performed for all the patients that enrolled. Serum samples were collected at 12, 24, and 48 weeks for patients treated with Peg-IFN-α, or at 1 year, 3 years, and 5 years for patients treated with NAs. Laboratory testing of HBsAg, HBsAb, HBeAg, HBeAb, HBcAb, HBV DNA, ALT, and AST was done. We observed a significantly lower frequency of HBsAb-specific B cells in patients with chronic HBV than in healthy individuals . In the Peg-IFN-α-treated group, 41.2% of patients with baseline HBsAb-specific B cells achieved HBsAg seroconversion, while only 13.6% of patients without baseline HBsAb-specific B cells achieved HBsAg seroconversion (p = 0.006). By logistic regression analysis, patients with baseline HBsAb-specific B cells and HBsAg ≤ 1500 had higher HBsAg clearance at the end of treatment (p < 0.05). In the NA-treated group, 58.3% of patients with baseline HBsAb-specific B cells achieved HBeAg seroconversion, whereas only 30.0% of patients without baseline HBsAb-specific B cells achieved HBeAg seroconversion (p = 0.114). Our result revealed that baseline HBsAb-specific B cells by ELISpot assay might be a valuable predictive biomarker of HBsAg or HBeAg seroconversion in patients with chronic HBV on treatment.

To facilitate the achieving of the goal of "eliminating viral hepatitis as a major public health threat by 2030" set by the World Health Organization, the Chinese Society of Hepatology together with the Chinese Society of Infectious Diseases (both are branches of the Chinese Medical Association) organized a panel of experts and updated the guidelines for prevention and treatment of chronic hepatitis B in China (version 2022). With the support of available evidence, this revision of the guidelines focuses on active prevention, large scale testing, and expansion of therapeutic indication of chronic hepatitis B with the aim of reducing the hepatitis B related disease burden.

Previous studies have indicated that HBV pregenome RNA (HBV pgRNA) could predict HBeAg seroconversion among the chronic hapatitis B (CHB) patients treated with pegylated interferon (Peg-IFN) or nucleos(t)ide analogues (NAs). However, the data about the prediction of HBV pgRNA for spontaneous HBeAg seroconversion is limited.

One hundred thirteen CHB patients with HBeAg-positive in the immune active phase were followed up for 76 weeks without antiviral treatment. Based on the laboratory test results of liver function, HBeAg, anti-HBe, and HBV DNA at week 76, patients were assigned to two groups: spontaneous HBeAg seroconversion (group A, n = 18) and non-spontaneous HBeAg seroconversion group. Among the latter group, 36 patients were selected as controls (group B, n = 36).

At week 12, between group A and group B, there was a significant difference in the level of HBV pgRNA (group A 6.35 ± 1.24 log10 copies/ml and group B 7.52 ± 0.79 log10 copies/ml, P = 0.001), and the difference enlarged at week 28. The receiver operating characteristic curves (AUROCs) of the HBV pgRNA level and the ∆HBV pgRNA at week 28 were 0.912 (P = 0.001, 95% CI: 0.830-0.994), and 0.934 (P = 0.001, 95% CI: 0.872-0.996), respectively. The optimal cutoffs of HBV pgRNA and the reduction from baseline (∆HBV pgRNA) at week 28 for spontaneous HBeAg seroconversion prediction were 5.63 log10 copies/ml and 1.85 log10 copies/ml, respectively. The positive predictive value and negative predictive value of HBV pgRNA and ∆HBV pgRNA at week 28 were 86.7% and 87.2%, 87.5% and 89.5%, respectively. And the combination of the HBV pgRNA level and the HBV pgRNA decreased could provide better prediction.

HBV pgRNA is a sound predictor for spontaneous HBeAg seroconversion among the CHB patients in immune active phase. Dynamic monitoring of HBV pgRNA is helpful for clinical treatment decision.

Over 250 million people are living with chronic infection caused by the hepatitis B virus (HBV). HBV has three surface proteins, namely small (SHBs), medium (MHBs) and large (LHBs), and they play different roles in the virus life cycle. The approved hepatitis B vaccine only contains the SHBs protein and many studies have focused on characterising the functional domains in SHBs. Although the LHBs protein is less studied, recent studies have shown that it plays important roles in mediating viral entry, replication and assembly. Over the years, there have been major advancements in monoclonal antibody (mAb) discovery tools and multiple mAbs have been developed to specifically target the preS1 domain in LHBs. We summarise the HBV infection systems and antibody discovery strategies that have been utilised by various research groups to assess the potential use of anti-preS1 mAbs as therapeutic antibodies against HBV or in the development of new diagnostic assays.

Two novel assays have been developed, iTACT-hepatitis B core-related antigen (iTACT-HBcrAg) and iTACT-hepatitis B surface antigen (iTACT-HBsAg) assays. We investigated the longitudinal profiles of iTACT-HBcrAg- and -HBsAg in patients with HBsAg seroclearance (SC) (<0.05 IU/mL). This study comprises 60 HBV-infected patients with HBsAg SC, 27 in chronic hepatitis/liver cirrhosis (CH/LC) group and 33 in inactive carrier (IC) group. Longitudinal profiles of iTACT-HBcrAg and -HBsAg were examined using stored serum samples. The median period from HBsAg SC to iTACT-HBcrAg loss or to the last observation was longer in the CH/LC group than the IC group (39 vs. -3 months, p = 0.004), but this tendency was not observed in that by iTACT-HBsAg. Comparing the times of iTACT-HBcrAg and -HBsAg loss, the rate of patients who lost HBcrAg first was significantly higher in the IC group (p = 0.008). The cumulative incidence rate of iTACT-HBcrAg loss after HBsAg SC was higher in the IC group that the CH/LC group (p = 0.002). Patients in the CH/LC group had higher rates of detectable iTACT-HBcrAg than those in the IC group after HBsAg SC, suggesting that the presence of HBcrAg possibly contribute to the progression of chronic hepatitis B.

Hepatitis E virus (HEV) is a significant public health concern worldwide. Pregnant women are at high risk of severe HEV infection. Various adverse outcomes in pregnant women related to HEV infection have been well documented in low-income and middle-income countries with poor sanitation. However, previous studies have provided inconsistent conclusions regarding the effects of HEV infection on the health of pregnant women and their infants in developed countries and contemporary China. In China, previous studies on HEV in pregnant women mainly focused on anti-HEV IgM and/or anti-HEV IgG. In this study, 4244 pregnant women were retrospectively analyzed for HEV-related markers. The positive rates of HEV antigen, HEV RNA, anti-HEV IgM, and anti-HEV IgG were 0.28%, 0.54%, 0.35%, and 10.49%, respectively. Among the 467 pregnant women who tested positive for at least one HEV-related marker, 92.93% (434) were positive for anti-HEV IgG only and 0.21% (1) were positive for HEV antigen, anti-HEV IgM, and anti-HEV IgG. Although the prevalence of anti-HEV IgG significantly increased with age, the prevalence of anti-HEV IgM, HEV RNA, and HEV antigen did not differ among pregnant women of different ages. Thirty-three pregnant women were positive for at least one of anti-HEV IgM, HEV antigen, and HEV RNA, and these individuals were recently or currently infected with HEV. None of the 33 pregnant women exhibited obvious clinical symptoms. Of the 33 pregnant women, 39.39% (13) experienced adverse fetal outcomes, including preterm birth, fetal distress, and low birth weight, the incidence of which was significantly higher than in pregnant women who were not recently or currently infected with HEV. These findings suggest that maternal HEV infection may impact the health of fetuses; thus, these results may contribute to the development of appropriate public health interventions for this population.

Management of chronic hepatitis D (CHD) has entered a new era. In this new era, the virus entry inhibitor bulevirtide has received conditional approval as a treatment for compensated CHD. Three phase 3 studies with two new compounds are ongoing for the treatment of CHD. In this context, surrogate markers of treatment efficacy have been well defined for chronic hepatitis B (CHB) (7) and chronic hepatitis C (8) but not for CHD. The aim of this review is to give a perspective on treatment endpoints in CHD. For this, we took guidance from CHB studies and tried to make suggestions which differed according to finite versus prolonged treatment durations and also took into account the different characteristics of the new compounds.

Hepatitis B surface antigen (HBsAg) consists of six components of large/middle/small HBs proteins (L/M/SHBs) with non-glycosylated (ng)- or glycosylated (g)- isomers at sN146 in their shared S domain. g-SHBs plays a crucial role in hepatitis B virus (HBV) secretion. However, the host and viral factors impacting sN146 status in natural HBV infection remain revealed mainly due to the technical difficulty in quantifying g-SHBs and ng-SHBs in serum samples.

To establish a standardized Western blot (WB) assay (WB-HBs) for quantifying the SHBs isomers in serum samples of 328 untreated hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) patients with genotype B or C HBV infection. The 1.3-mer HBV genotype B or C plasmids were transiently transfected into HepG2 cells for in vitro study.

The median level of ng-SHBs was significantly higher than that of g-SHBs (N = 328) (2.6 vs. 2.0 log₁₀, P < 0.0001). The median g-/ng-SHBs ratio in female patients (N = 75) was significantly higher than that of male patients (N = 253) (0.35 vs. 0.31, P < 0.01) and the median g-/ng-SHBs ratio in genotype C patients (N = 203) was significantly higher than that of the genotype B patients (N = 125) (0.33 vs. 0.29, P < 0.0001).

Our findings suggest that the g-/ng-SHBs ratio is host-sex-biased and viral genotype dependent in treatment naïve patients with HBeAg-positive chronic hepatitis B, which indicates the glycosylation of SHBs could be regulated by both host and viral factors. The change of ratio may reflect the fitness of HBV in patients, which deserves further investigation in a variety of cohorts such as patients with interferon or nucleos(t)ide analogues treatment.

Chronic hepatitis B (CHB) is rarely cured using available treatments. Barriers to cure are: 1) persistence of reservoirs of hepatitis B virus (HBV) replication and antigen production (HBV DNA); 2) high burden of viral antigens that promote T cell exhaustion with T cell dysfunction; 3) CHB-induced impairment of immune responses.

We discuss options for new therapies that could address one or more of the barriers to functional cure, with particular emphasis on the potential role of immunotherapy.

Ideally, a sterilizing cure for CHB would translate into finite therapies that result in loss of HBV surface antigen and eradication of HBV DNA. Restoration of a functional adaptive immune response, a key facet of successful CHB treatment, remains elusive. Numerous strategies targeting the high viral DNA and antigen burden and aiming to restore the host immune responses will enter clinical development in coming years. Most patients are likely to require combinations of several drugs, personalized according to virologic and disease characteristics, patient preference, accessibility, and affordability. The management of CHB is a global health priority. Expedited drug development requires collaborations between regulatory agencies, scientists, clinicians, and within the industry to facilitate testing of the best drug combinations.