How to achieve functional cure of HBV: Stopping NUCs, adding interferon or new drug development?

Virological markers for clinical trials in chronic viral hepatitis

Chronic hepatitis virus infections remain a major public health problem, despite significant therapeutic advances over the past two decades. Considerable progress has been made in the treatment of chronic viral hepatitis, but continued efforts are needed to develop and bring to market new drugs to fill the gaps in the current therapeutic armamentarium. Thus, clinical trials to assess the safety and efficacy of these new therapeutic approaches, including the selection of reliable and objective treatment endpoints, are still needed. Virological biomarkers play an important role in the diagnosis, monitoring, and evaluation of antiviral treatment efficacy. They are often used as primary or secondary endpoints in the evaluation of new treatments for chronic viral hepatitis. However, these markers are not all equally informative. The aim of this review article is to provide a comprehensive overview of the available virological tests for chronic viral hepatitis due to hepatitis B, D, C and E viruses, the information they provide and lack, the specific challenges associated with each, and their use in clinical trials of new treatments.

Effect of tenofovir versus entecavir on the long-term prognosis in hepatocellular carcinoma patients with concurrent metabolic dysfunction-associated steatotic liver disease and hepatitis B

BACKGROUND

Currently, there remains ongoing controversy about the selection of postoperative antiviral drugs for hepatocellular carcinoma (HCC) patients with concurrent metabolic dysfunction-associated steatotic liver disease (MASLD) and hepatitis B virus (HBV) infection (HPMH) who underwent hepatectomy.

METHOD

A multivariate Cox proportional hazards model and a propensity score matching (PSM) analysis were implemented to ensure equal baseline characteristics. The Kaplan‒Meier survival curves were employed for prognosis comparison between the two groups.

RESULTS

This study included 225 HPMH who all received post-hepatectomy antiviral therapy; with 107 in the tenofovir disoproxil fumarate (TDF) group and 118 in the entecavir (ETV) group. In the entire cohort, according to the multivariate analysis, patients in the TDF group showed better recurrence-free survival (RFS) (HR = 0.78; 95% CI, 0.55-0.95; p = 0.030) and overall survival (OS) (HR = 0.52; 95% CI, 0.30-0.97; p = 0.021) than those in the ETV group. After executing a PSM analysis, Kaplan‒Meier survival curve analysis disclosed significant differences for both RFS and OS between the two groups (p = 0.03 and p = 0.01, respectively).

CONCLUSIONS

In summary, our study suggests a more significant association of TDF in improving RFS and OS than ETV in HPMH who underwent hepatectomy through multivariate and PSM analysis. These findings indicate that the choice of antiviral drugs in HPHM holds crucial significance in guiding patient long-term prognosis.

Preclinical and clinical antiviral characterization of AB-836, a potent capsid assembly modulator against hepatitis B virus

HBV capsid assembly modulators (CAMs) target the core protein and inhibit pregenomic RNA encapsidation and viral replication. HBV CAMs also interfere with cccDNA formation during de novo infection, which in turn suppresses transcription and production of HBV antigens. In this report, we describe the antiviral activities of AB-836, a potent and highly selective HBV CAM. AB-836 inhibited viral replication (EC50 = 0.010 μM) in HepDE19 cells, and cccDNA formation (EC50 = 0.18 μM) and HBsAg production (EC50 = 0.20 μM) in HepG2-NTCP cells during de novo infection. AB-836 showed broad genotype coverage, remained active against variants resistant to nucleos(t)ide analogs, and demonstrated improved antiviral potency against core variants resistant to other CAMs. AB-836 also mediated potent inhibition of HBV replication in a hydrodynamic injection mouse model, reducing both serum and liver HBV DNA. In a Phase 1 clinical study, 28 days of once-daily AB-836 oral dosing at 50, 100, and 200 mg resulted in mean serum HBV DNA declines of 2.57, 3.04, and 3.55 log10 IU/mL from baseline, respectively. Neither on-treatment viral rebound nor the emergence of viral resistance was observed during the 28-day treatment period. Furthermore, HBV DNA sequence analysis of baseline samples from the Phase 1 study revealed that 51.4% of the chronic hepatitis B participants contained at least one core polymorphism within the CAM-binding pocket, suggesting that genetic variations exist at this site. While AB-836 was discontinued due to clinical safety findings, data from the preclinical and clinical studies could help inform future optimization of HBV CAMs.

A nation-wide medical record database study: Value of hepatitis B surface antigen loss in chronic hepatitis B patients in Japan

AIM

Hepatitis B surface antigen (HBsAg) seroclearance is considered to be one of the best surrogate endpoints of functional cure for hepatitis B virus (HBV) infection. However, evidence regarding the relationship between achieving HBsAg seroclearance or a low baseline HBsAg level, and long-term clinical outcomes in Japanese patients with chronic HBV infection remains to be confirmed in a real-world setting.

METHODS

A retrospective observational cohort study was performed with an electronic medical record database, including data from 230 hospitals across Japan. Chronic HBV infection was defined as two consecutive, positive HBsAg laboratory measurements for HBV infection. The date of the second positive was used as a baseline to identify subsequent HBsAg seroclearance and liver disease progression.

RESULTS

In the database, 2523 patients with chronic HBV infection were identified as the chronic hepatitis B (CHB) cohort. Among the CHB cohort with an average observational period of 5.19 ± 3.87 years, 202 patients (8%) achieved HBsAg seroclearance after baseline. They had a lower risk of developing hepatocellular carcinoma (HCC) (adjusted hazard ratio [aHR] 0.206, p < 0.01) and cirrhosis (aHR 0.361, p < 0.01). When the CHB cohort was stratified into two groups based on baseline HBsAg levels (<100 IU/mL and ≥100 IU/mL), patients with a lower baseline level of HBsAg (<100 IU/mL) had a lower risk of developing liver disease (HCC aHR 0.600, p < 0.01; cirrhosis aHR 0.618, p < 0.05).

CONCLUSIONS

These results confirm the clinical significance of HBsAg seroclearance and low HBsAg level at baseline with respect to long-term outcomes of patients with CHB in the Japanese population.

The efficacy and safety of addition of pegylated interferon to long-term nucleos(t)ide analogue therapy on functional cure of chronic hepatitis B patient: a systematic review and meta-analysis

Objective

This meta-analysis aims to assess the efficacy and safety of adding pegylated interferon (Peg-IFN) to long-term nucleos(t)ide analogs (NAs) treatment for achieving functional cure in patients with chronic hepatitis B (CHB).

Methods

This meta-analysis was registered in PROSPERO (CRD42024519116). We searched PubMed, Embase, Cochrane Library and Web of Science for randomized controlled trials that compared adding Peg-IFN to long-term NAs with NAs alone for the treatment of CHB. Relative risks (RR) and 95% confidence interval (CI) were pooled using a random-effects model.

Results

Seven trials with 692 participants were included. Compared to NAs monotherapy, sequential combination therapy significantly increased the HBsAg seroclearance rate (RR 4.37, 95%CI: 1.92-9.55; I2 = 0%) and HBsAg seroconversion rate (RR 3.98, 95%CI: 1.50-10.54; I2 = 0%), and the results reached statistical significance. Compared to NAs monotherapy, sequential combination therapy showed a significant increase in HBeAg seroclearance rate (RR 2.04; 95%CI: 0.47-8.82; I2 = 73%) and HBeAg seroconversion rate (RR 2.10; 95%CI: 0.41-10.71; I2 = 67%), but did not reach statistical significance. Sequential combination therapy was more likely to experience adverse events. Although most reactions are mild and reversible, vigilant monitoring for treatment-related adverse events is essential, with prompt intervention when needed.

Conclusion

For CHB patients on long-term NAs treatment, sequential combination therapy boosts HBsAg seroclearance and HBsAg seroconversion rates compared to monotherapy. However, it may increase adverse events. Additional studies are needed to thoroughly evaluate its clinical effectiveness, given the current limited research available.

Systematic Review Registration

PROSPERO, identifier CRD42024519116.

A case report: cccDNA and pgRNA remain positive in liver tissue in a chronic hepatitis B patient with functional cure

Hepatitis B surface antigen (HBsAg) seroclearance is recommended as the ideal endpoint for nucleos(t)ide analog (NA) treatments. Functional cure of chronic hepatitis B (CHB) is defined as having undetectable serum hepatitis B virus (HBV) deoxyribonucleic acid and serum HBsAg. We report a functional cure case of CHB with a family history of hepatocellular carcinoma (HCC) after long-term NA therapy. Despite achieving functional cure for over 7 years, both HBV covalently closed circular deoxyribonucleic acid (cccDNA) and pregenomic ribonucleic acid (pgRNA) remain positive in the liver tissue of the patient, indicating that a sterilizing cure has not been achieved. This case highlights the importance of active surveillance of HBV cccDNA and pgRNA for sterilizing the cure and risk of HCC.

Optimization of culture conditions for HBV-specific T cell expansion in vitro from chronically infected patients

BACKGROUND

Hepatitis B virus (HBV) clearance depends on an effective adaptive immune response, especially HBV-specific T cell-mediated cellular immunity; however, it is difficult to produce enough HBV-specific T cells effectively.

RESULTS

In this work, we investigated the proportions of stimulated cells, serum, and culture media as the three primary factors to determine the most effective procedure and applied it to HLA-A2 (+) people. In parallel, we also examined the correlation between clinical parameters and HBV-specific immunity. Concerning amplification efficiency, 4 × 105 cells stimulation was superior to 2 × 106 cells stimulation, AIM-V medium outperformed 1640 medium, and fetal bovine serum (FBS) exceeded human AB serum under comparable conditions. As expected, this procedure is also suitable for developing HBV-specific CD8 + T cells in HLA-A2(+) individuals. Expanded HBV-specific T cell responses decreased with treatment time and were negatively correlated with HBV DNA and HBsAg. Furthermore, the number of HBV-specific IFN-γ + SFCs was strongly correlated with the ALT level and negatively correlated with the absolute lymphocyte count and the ALB concentration.

CONCLUSIONS

We confirm that stimulating 4 × 105 PBMCs in AIM-V medium supplemented with 10% FBS is the best approach and that HBeAg, HBsAg, and ALB are independent predictors of HBV-specific T-cell responses.

Efficacy of short-term Peg-IFN α-2b treatment in chronic hepatitis B patients with ultra-low HBsAg levels: a retrospective cohort study

PURPOSE

Peginterferon alfa-2b (Peg-IFN α-2b) has demonstrated superior efficacy over nucleos(t)ide analogs (NAs) in the treatment of chronic hepatitis B (CHB), particularly among patients with low levels of hepatitis B surface antigen (HBsAg). This study aims to determine whether patients with ultra-low HBsAg levels (< 200 IU/mL) can achieve significantly higher clinical cure rates with abbreviated courses of Peg-IFN α-2b therapy.

METHODS

In this retrospective analysis, CHB patients with HBsAg levels below 200 IU/mL were categorized into a Peg-IFN α-2b group and a control group. The Peg-IFN α-2b group received Peg-IFN α-2b for a minimum of 24 weeks, with the possibility of early discontinuation upon achieving HBsAg clearance, and were followed through week 48. The control group remained untreated for hepatitis B virus (HBV), and was observed for 24 weeks. HBsAg clearance rates were compared between groups. Univariate and multivariate logistic regression analyses were employed to identify factors associated with HBsAg clearance .

RESULTS

By week 24, the HBsAg clearance rate in the Peg-IFN α-2b group was notably 52.1% (38/73), contrasting sharply with the mere 1.3% (1/77) observed in the control group. Within the Peg-IFN α-2b group, a substantial 97.3% (71/73) of patients noted a reduction in HBsAg levels. Besides, the decision to continue or discontinue treatment after the 24-week mark had no significant impact on the HBsAg clearance rate at week 48. Multivariable analysis pinpointed baseline HBsAg levels (OR = 0.984, p = 0.001) and the presence of fatty liver (OR = 5.960, p = 0.033) as independent predictors of HBsAg clearance.

CONCLUSION

Our findings confirm that a 24-week course of Peg-IFN α-2b yields robust efficacy in CHB patients with ultra-low HBsAg levels. Prolonging treatment beyond the 24-week threshold is deemed unnecessary. Both baseline HBsAg level and the presence of fatty liver emerged as significant predictors for HBsAg clearance.

High accuracy model for HBsAg loss based on longitudinal trajectories of serum qHBsAg throughout long-term antiviral therapy

OBJECTIVE

Hepatitis B surface antigen (HBsAg) loss is the optimal outcome for patients with chronic hepatitis B (CHB) but this rarely occurs with currently approved therapies. We aimed to develop and validate a prognostic model for HBsAg loss on treatment using longitudinal data from a large, prospectively followed, nationwide cohort.

DESIGN

CHB patients receiving nucleos(t)ide analogues as antiviral treatment were enrolled from 50 centres in China. Quantitative HBsAg (qHBsAg) testing was prospectively performed biannually per protocol. Longitudinal discriminant analysis algorithm was used to estimate the incidence of HBsAg loss, by integrating clinical data of each patient collected during follow-up.

RESULTS

In total, 6792 CHB patients who had initiated antiviral treatment 41.3 (IQR 7.6-107.6) months before enrolment and had median qHBsAg 2.9 (IQR 2.3-3.3) log10IU/mL at entry were analysed. With a median follow-up of 65.6 (IQR 51.5-84.7) months, the 5-year cumulative incidence of HBsAg loss was 2.4%. A prediction model integrating all qHBsAg values of each patient during follow-up, designated GOLDEN model, was developed and validated. The AUCs of GOLDEN model were 0.981 (95% CI 0.974 to 0.987) and 0.979 (95% CI 0.974 to 0.983) in the training and external validation sets, respectively, and were significantly better than those of a single qHBsAg measurement. GOLDEN model identified 8.5%-10.4% of patients with a high probability of HBsAg loss (5-year cumulative incidence: 17.0%-29.1%) and was able to exclude 89.6%-91.5% of patients whose incidence of HBsAg loss is 0. Moreover, the GOLDEN model consistently showed excellent performance among various subgroups.

CONCLUSION

The novel GOLDEN model, based on longitudinal qHBsAg data, accurately predicts HBsAg clearance, provides reliable estimates of functional hepatitis B virus (HBV) cure and may have the potential to stratify different subsets of patients for novel anti-HBV therapies.

HBcrAg values may predict virological and immunological responses to pegIFN-α in NUC-suppressed HBeAg-negative chronic hepatitis B

OBJECTIVE

Selected populations of patients with chronic hepatitis B (CHB) may benefit from a combined use of pegylated interferon-alpha (pegIFN-α) and nucleos(t)ides (NUCs). The aim of our study was to assess the immunomodulatory effect of pegIFN-α on T and natural killer (NK) cell responses in NUC-suppressed patients to identify cellular and/or serological parameters to predict better T cell-restoring effect and better control of infection in response to pegIFN-α for a tailored application of IFN-α add-on.

DESIGN

53 HBeAg-negative NUC-treated patients with CHB were randomised at a 1:1 ratio to receive pegIFN-α-2a for 48 weeks, or to continue NUC therapy and then followed up for at least 6 months maintaining NUCs. Serum hepatitis B surface antigen (HBsAg) and hepatitis B core-related antigen (HBcrAg) levels as well as peripheral blood NK cell phenotype and function and HBV-specific T cell responses upon in vitro stimulation with overlapping HBV peptides were measured longitudinally before, during and after pegIFN-α therapy.

RESULTS

Two cohorts of pegIFN-α treated patients were identified according to HBsAg decline greater or less than 0.5 log at week 24 post-treatment. PegIFN-α add-on did not significantly improve HBV-specific T cell responses during therapy but elicited a significant multispecific and polyfunctional T cell improvement at week 24 post-pegIFN-α treatment compared with baseline. This improvement was maximal in patients who had a higher drop in serum HBsAg levels and a lower basal HBcrAg values.

CONCLUSIONS

PegIFN-α treatment can induce greater functional T cell improvement and HBsAg decline in patients with lower baseline HBcrAg levels. Thus, HBcrAg may represent an easily and reliably applicable parameter to select patients who are more likely to achieve better response to pegIFN-α add-on to virally suppressed patients.

Exploration of 1-(indolin-1-yl)-2-(thiazol-2-yl)ethan-1-one derivatives as novel anti-HBV agent with potential TLR7-agonistic effect

Hepatitis B virus (HBV) infection, as a serious global public health issue, is closely related to the immune dysfunction. Herein, thirty-seven 1-(indolin-1-yl)-2-(thiazol-4-yl)ethan-1-one derivatives were prepared as potential immunomodulatory anti-HBV agents. Anti-HBV activity evaluation confirmed compound 11a could significantly suppress the HBV DNA replication in both wild and resistant HBV stains, with IC50 values of 0.13 μM and 0.36 μM, respectively. Preliminary action mechanism studies showed that 11a had an inhibitory effect on cellular HBsAg secretion and could effectively activate TLR7, thereby inducing the secretion of TLR7-regulated cytokines IL-12, TNF-α and IFN-α in human PBMC cells. SPR analysis confirmed that 11a could bind to TLR7 protein with an affinity of 7.06 μM. MD simulation predicted that 11a could form tight interactions with residues in the binding pocket of TLR7. Physicochemical parameters perdition and pharmacokinetic analysis indicated that 11a displayed relatively favorable drug-like properties. Considering all the results, compound 11a might be a promising lead for developing novel immunomodulatory anti-HBV agents.

Elevated Hepatitis B virus RNA levels in hepatocellular carcinoma patients compared to cirrhotic individuals: A propensity score matched analysis

BACKGROUND

To delineate the levels of serum Hepatitis B virus (HBV) RNA in patients with HBV-related hepatocellular carcinoma (HCC) and study comparisons with those of individuals afflicted with cirrhosis.

METHODS

Adult patients diagnosed with HBV-related cirrhosis or HCC (initial diagnosis) were enrolled in the cross-sectional study. Serum HBV DNA level was quantified through a real-time polymerase chain reaction assay with a lower limit of quantification (LLQ) of 20 IU/ml. Additionally, serum HBV RNA was quantified employing RNA real-time fluorescence thermostatic amplification detection technology with LLQ of 100 copies/ml. Propensity score matching (PSM) was conducted to ensure balance in between-group confounders.

RESULTS

A total of 187 patients (47 with HCC and 140 with cirrhosis) were recruited, among whom 140 (74.9%) had undergone antiviral therapy prior to their inclusion, with varying durations. Serum HBV RNA was detectable in 89.4% of HCC patients at the time of carcinoma diagnosis. After PSM, individuals with HCC exhibited significantly elevated levels of serum HBV DNA and HBV RNA compared to those with cirrhosis (median lgHBV RNA 3.1 vs 2.0 copies/ml, P = 0.001). Subgroup analysis, including 38 patients who exhibited ultrasensitive HBV DNA negativity, revealed similar results (median lgHBV RNA 3.0 vs 0.0 copies/ml, P < 0.001).

CONCLUSIONS

Serum HBV RNA levels were significantly higher in HBV-related HCC patients compared to cirrhotic patients. The presence of serum HBV RNA positivity or elevated levels was associated with the onset of HCC.

Investigating the role of GTPase in inhibiting HBV replication and enhancing interferon therapy efficacy in chronic hepatitis B patients

BACKGROUND

Interferon-alpha (IFNα) is a common treatment for chronic hepatitis B virus (HBV) infection, but its efficacy varies widely among patients. GTPASE, an interferon-stimulated gene (ISG), has recently been identified as a factor in antiviral immunity, though its role in HBV infection is not fully understood.

OBJECTIVE

This study investigates the role of GTPASE in enhancing the antiviral effects of IFNα against HBV and elucidates its mechanism of action.

METHODS

We analyzed the impact of GTPASE overexpression and silencing on HBV replication and clearance in HBV-infected cells. Molecular docking studies assessed the interaction between GTPASE and HBV surface antigens (HBs). Clinical samples from HBV patients undergoing Peg-IFNα treatment were also evaluated for GTPASE expression and its correlation with treatment efficacy.

RESULTS

Overexpression of GTPASE led to significant inhibition of HBV replication, increased HBeAg seroconversion, and enhanced HBsAg clearance. GTPASE directly bound to HBs proteins, reducing their levels and affecting viral particle formation. Silencing GTPASE reduced these effects, while combined treatment with Peg-IFNα and GTPASE overexpression further improved antiviral outcomes. Mutational analysis revealed that specific sites in GTPASE are crucial for its antiviral activity.

CONCLUSIONS

GTPASE acts as a positive regulator in IFNα-induced antiviral immunity against HBV. It enhances the therapeutic efficacy of IFNα by targeting HBs and modulating viral replication. GTPASE levels may serve as a predictive biomarker for response to Peg-IFNα therapy, highlighting its potential for improving individualized treatment strategies for chronic HBV infection.

Lymph node-targeted STING agonist nanovaccine against chronic HBV infection

Chronic hepatitis B virus (HBV) infection is a global health problem that substantially increases the risk of developing liver disease. The development of a novel strategy to induce anti-HB seroconversion and achieve a long-lasting immune response against chronic HBV infection remains challenging. Here, we found that chronic HBV infection affected the signaling pathway involved in STING-mediated induction of host immune responses in dendritic cells (DCs) and then generated a lymph node-targeted nanovaccine that co-delivered hepatitis B surface antigen (HBsAg) and cyclic diguanylate monophosphate (c-di-GMP) (named the PP-SG nanovaccine). The feasibility and efficiency of the PP-SG nanovaccine for CHB treatment were evaluated in HBV-carrier mice. Serum samples were analyzed for HBsAg, anti-HBs, HBV DNA, and alanine aminotransferase levels, and liver samples were evaluated for HBV DNA and RNA and HBcAg, accompanied by an analysis of HBV-specific cellular and humoral immune responses during PP-SG nanovaccine treatment. The PP-SG nanovaccine increased antigen phagocytosis and DC maturation, efficiently and safely eliminated HBV, achieved a long-lasting immune response against HBV reinjection, and disrupted chronic HBV infection-induced immune tolerance, as characterized by the generation and multifunctionality of HBV-specific CD8+ T and CD4+ T cells and the downregulation of immune checkpoint molecules. HBV-carrier mice immunized with the PP-SG nanovaccine achieved partial anti-HBs seroconversion. The PP-SG nanovaccine can induce sufficient and persistent viral suppression and achieve anti-HBs seroconversion, rendering it a promising vaccine candidate for clinical chronic hepatitis B therapy.

Risk factors related to low-level viraemia in chronic hepatitis B patients receiving entecavir treatment

Background

About 20% of on-treatment patients with chronic hepatitis B (CHB) experienced low-level viraemia (LLV), which is associated with persistent low-grade inflammation, fibrosis progression, and increased risk of hepatocellular carcinoma. We aimed to investigate the high-risk factors related to LLV.

Methods

In this retrospective study, patients receiving entecavir (ETV) treatment from January 2018 to January 2023 were enrolled, and were divided into a LLV (HBV DNA 20-2000 IU/mL) cohort and a complete virological response (CVR) (HBV DNA < 20 IU/mL) cohort according to the virological response at week 48 posttreatment. Treatment baseline characteristics were retrieved from electronic medical records. Multivariate logistic regression was performed.

Results

Totally, 1653 patients were enrolled, male patients accounted for 73.0%; the median age was 44 years; the mean HBV DNA level was 5.9 Log10 IU/ml. Among them, 472 (28.6%) experienced LLV. Multivariate analysis showed that HBeAg positivity (OR = 2.650, 95% CI: 2.000-3.511, p < 0.001), HBV DNA ≥ 6.0 Log10 IU/mL (OR = 1.370, 95% CI: 1.054-1.780, p = 0.019), qHBsAg ≥ 9000 IU/mL (OR = 4.472, 95% CI: 3.410-5.866, p < 0.001), cirrhosis (OR = 1.650, 95% CI: 1.234-2.207, P = 0.001), LSM ≥ 13.0 kPa (OR = 1.644, 95% CI: 1.203-2.246, p = 0.002), and PLT < 100×109/L (OR = 1.450, 95% CI: 1.094-1.922, p = 0.010) at baseline were related to the development of LLV.

Conclusions

High HBV DNA/HBsAg quantification/LSM, low PLT, HBeAg positivity, and liver cirrhosis were high-risk factors associated with LLV in patients receiving entecavir treatment.

Surveillance for Hepatocellular Carcinoma in Patients with Successfully Treated Viral Disease of the Liver: A Systematic Review

Background

Surveillance for hepatocellular carcinoma (HCC) has been proven to increase the proportion of tumors detected at early stages and the chance of receiving curative therapies, reducing mortality by about 30%.

Summary

Current recommendations consist of a semi-annual abdominal ultrasound with or without serum alpha-fetoprotein measurement in patients with cirrhosis and specific subgroups of populations with chronic viral hepatitis. Antiviral therapies, such as nucleot(s)ide analogs that efficiently suppress the replication of hepatitis B virus (HBV) and direct-acting antiviral drugs able to eliminate the hepatitis C virus (HCV) in >90% of patients, have radically changed the outcomes of viral liver disease and decreased, but not eliminated, the risk of HCC in both cirrhotic and non-cirrhotic patients. HCC risk is a key starting point for implementing a cost-effective surveillance and should also guide the decision-making process concerning its modality. As the global number of effectively treated viral patients continues to rise, there is a pressing need to identify those for whom the benefit-to-harm ratio of surveillance is favorable and to determine how to conduct cost-effective screening on such patients.

Key Messages

This article addresses this topic and attempts to determine which patients should continue HCC surveillance after HBV suppression or HCV eradication, based on cost-effectiveness principles and the fact that HCC risk declines over time. We also formulate a proposal for a surveillance algorithm that switches the use of surveillance for HCC from the "one-size-fits-all" approach to individualized programs based on oncologic risk (precision surveillance).

Systematic review and meta-analysis: de novo combination of nucleos(t)ide analogs and pegylated interferon alpha versus pegylated interferon alpha monotherapy for the functional cure of chronic hepatitis B

Introduction: Chronic hepatitis B (CHB) is a worldwide infectious disease caused by hepatitis B virus (HBV). Optimizing antiviral treatment strategies could improve the functional cure (FC) rate of patients with CHB. This study aims to systematically review the FC rate of the de novo combination of nucleos(t)ide analogs (NAs) and pegylated interferon α (PEG-IFNα) versus that of PEG-IFNα monotherapy for CHB. Methods: Databases were searched until 31 December 2023. Selected studies included randomized controlled trials on the de novo combination of NAs and PEG-IFNα versus PEG-IFNα monotherapy for 48 weeks in patients with CHB to achieve FC, which was defined as hepatitis B surface antigen (HBsAg) loss and/or HBsAg seroconversion. Meta-analysis was conducted in accordance with the efficacy at the end of treatment and different time points during follow-up. Results: A total of 10 studies, encompassing 2,339 patients in total, were included. Subgroup analysis was conducted in accordance with whether first-line NAs were used. It found no statistically significant difference between HBsAg loss and HBsAg seroconversion at the end of treatment. Serum HBV DNA <500 copies/mL significantly differed between the two groups at the end of treatment and did not significantly differ during follow-up. Meanwhile, HBsAg loss and HBsAg seroconversion showed statistically significant differences at 24 weeks of follow-up. By contrast, no statistically significant difference was found in HBsAg loss at 48 weeks of follow-up. Discussion: Without distinguishing the eligible preponderant population, the efficacy of the de novo combination of NAs and PEG-IFNα in treating patients with CHB was not superior to that of PEG-IFNα monotherapy. Systematic Review Registration: PROSPERO, identifier CRD42022325239.

Identification of risk groups for advanced liver fibrosis in the general population using the Fibrosis-3 index

Background and Aim

We conducted a study using the Fibrosis-3 (FIB-3) index, which is the established age-independent index of fibrosis in nonviral liver disease and addresses the limitations of the FIB-4 index in older age group, to assess the liver fibrosis risk among diverse demographic groups in the general population.

Methods

We analyzed 31 327 individuals who underwent health examinations between 2013 and 2020 and investigated the distribution of the FIB-3 index by age group. In addition, we examined the age distribution of the FIB-3 index stratified by background factors, such as sex, body mass index (BMI), alcohol consumption habits, and the presence or absence of fatty liver.

Results

In terms of age-specific distribution, the FIB-3 index remained below 1.5 in >90% of cases until the age of 50 years but exceeded 1.5 beyond the age of 50 years, in approximately 30% among those aged 70 years. Notably, the FIB-3 index above 31 years old was significantly higher in men than in women. Among the different BMI categories, individuals with BMI < 18.5 exhibited the highest prevalence of fibrosis. Habitual drinkers had a higher proportion with FIB-3. index ≥1.5, and some had FIB-3 index ≥2.5, raising the suspicion of advanced hepatic fibrosis. No distinct association was identified between the FIB-3 index and the presence of fatty liver.

Conclusions

The FIB-3 index was useful for identifying cases of advancing hepatic fibrosis in a health checkup population. Liver fibrosis progresses with age in the general population, especially among men, those with low BMI, and habitual drinkers.

HeberNasvac: Development and Application in the Context of Chronic Hepatitis B

The immune system plays a central role in controlling acute hepatitis B infection and in patients resolving chronic hepatitis B (CHB). Given that 221 million (75%) of CHB patients reside in low- and middle-income countries, the development of a vaccine with therapeutic properties represents a rational and cost-effective approach more than a romantic endeavor. This review systematically analyzes the key variables related to the safety, efficacy, and effectiveness of CHB treatments. HeberNasvac experience is revisited for addressing the challenges and potentialities of therapeutic vaccines, as well as the current roadblocks in research and development, registration, and large-scale implementation.

How to cite this article

Aguilar JC, Akbar SMF, Al-Mahtab M, et al. HeberNasvac: Development and Application in the Context of Chronic Hepatitis B. Euroasian J Hepato-Gastroenterol 2024;14(2):221-237.

Hepatitis B Virus Reactivation in Non-Liver Solid Organ Transplantation: Incidence and Risk Analysis

INTRODUCTION

Hepatitis B virus reactivation (HBVr) can occur in solid organ transplant (SOT) recipients with previously inactive hepatitis B virus (HBV) infection. Previous studies have reported that HBVr is generally less than 10% in nonliver SOT recipients with past HBV infection.

METHODS

We conducted a retrospective study from January 2018 to August 2023 at Mayo Clinic sites in Arizona, Florida, and Minnesota. We examined the antiviral prophylaxis strategy used and the characteristics of HBVr in hepatitis B core antibody-positive (HBcAb +) nonliver SOT adult recipients. Past HBV infection was defined as HBcAb + / hepatitis B surface antigen (HBsAg) -. Chronic HBV infection was defined as HBcAb + / HBsAg +.

RESULTS

A total of 180 nonliver SOT recipients were identified during the study period. Indefinite antiviral prophylaxis was utilized in 77 recipients, and none developed HBVr after transplantation. In 103 recipients without antiviral prophylaxis, the incidence of HBVr was 12% (12/97) and 33% (2/6) in those with past HBV infection and chronic HBV infection. The incidence of HBVr in patients with past HBV infection is 16% (8/50), 15% (3/20), and 5% (1/22) in kidney, heart, and lungs, respectively. HBVr was more frequent in those who received alemtuzumab. Among 14 recipients with HBVr, none had HBV-associated liver failure or death.

CONCLUSIONS

Our study observed a higher rate of HBVr (12%) in nonliver SOT recipients with past HBV infection compared to the previous studies. Further studies are needed to identify predictors of HBVr in nonliver SOT recipients and optimize antiviral prophylaxis guidance.

N-Hydroxypiridinedione: A Privileged Heterocycle for Targeting the HBV RNase H

Hepatitis B virus (HBV) remains a global health threat. Ribonuclease H (RNase H), part of the virus polymerase protein, cleaves the pgRNA template during viral genome replication. Inhibition of RNase H activity prevents (+) DNA strand synthesis and results in the accumulation of non-functional genomes, terminating the viral replication cycle. RNase H, though promising, remains an under-explored drug target against HBV. We previously reported the identification of a series of N-hydroxypyridinedione (HPD) imines that effectively inhibit the HBV RNase H. In our effort to further explore the HPD scaffold, we designed, synthesized, and evaluated 18 novel HPD oximes, as well as 4 structurally related minoxidil derivatives and 2 barbituric acid counterparts. The new analogs were docked on the RNase H active site and all proved able to coordinate the two Mg2+ ions in the catalytic site. All of the new HPDs effectively inhibited the viral replication in cell assays exhibiting EC50 values in the low μM range (1.1-7.7 μM) with low cytotoxicity, resulting in selectivity indexes (SI) of up to 92, one of the highest reported to date among HBV RNase H inhibitors. Our findings expand the structure-activity relationships on the HPD scaffold, facilitating the development of even more potent anti-HBV agents.

Tripartite motif-containing protein 21 is involved in IFN-γ-induced suppression of hepatitis B virus by regulating hepatocyte nuclear factors

The antiviral role of the tripartite motif-containing (TRIM) protein family , a member of the E3-ubiquitin ligase family, has recently been actively studied. Hepatitis B virus (HBV) infection is a major contributor to liver diseases; however, the host factors regulated by cytokine-inducible TRIM21 to suppress HBV remain unclear. In this study, we showed the antiviral efficacy of TRIM21 against HBV in hepatoma cell lines, primary human hepatocytes isolated from patient liver tissues, and mouse model. Using TRIM21 knock-out cells, we confirmed that the antiviral effects of interferon-gamma, which suppress HBV replication, are diminished when TRIM21 is deficient. Northern blot analysis confirmed a reduction of HBV RNA levels by TRIM21. Using Luciferase reporter assay, we also discovered that TRIM21 decreases the activity of HBV enhancers, which play a crucial role in covalently closed circular DNA transcription. The participation of the RING domain and PRY-SPRY domain in the anti-HBV effect of TRIM21 was demonstrated through experiments using deletion mutants. We identified a novel interaction between TRIM21 and hepatocyte nuclear factor 4α (HNF4α) through co-immunoprecipitation assay. More specifically, ubiquitination assay revealed that TRIM21 promotes ubiquitin-mediated proteasomal degradation of HNF4α. HNF1α transcription is down-regulated as a result of the degradation of HNF4α, an activator for the HNF1α promoter. Therefore, the reduction of key HBV enhancer activators, HNF4α and HNF1α, by TRIM21 resulted in a decline in HBV transcription, ultimately leading to the inhibition of HBV replication.IMPORTANCEDespite extensive research efforts, a definitive cure for chronic hepatitis B remains elusive, emphasizing the persistent importance of this viral infection as a substantial public health concern. Although the risks associated with hepatitis B virus (HBV) infection are well known, host factors capable of suppressing HBV are largely uncharacterized. This study elucidates that tripartite motif-containing protein 21 (TRIM21) suppresses HBV transcription and consequently inhibits HBV replication by downregulating the hepatocyte nuclear factors, which are host factors associated with the HBV enhancers. Our findings demonstrate a novel anti-HBV mechanism of TRIM21 in interferon-gamma-induced anti-HBV activity. These findings may contribute to new strategies to block HBV.

The dual function of cGAS-STING signaling axis in liver diseases

Numerous liver diseases, such as nonalcoholic fatty liver disease, hepatitis, hepatocellular carcinoma, and hepatic ischemia-reperfusion injury, have been increasingly prevalent, posing significant threats to global health. In recent decades, there has been increasing evidence linking the dysregulation of cyclic-GMP-AMP synthase (cGAS)-stimulator of interferon gene (STING)-related immune signaling to liver disorders. Both hyperactivation and deletion of STING can disrupt the immune microenvironment dysfunction, exacerbating liver disorders. Consequently, there has been a surge in research investigating medical agents or mediators targeting cGAS-STING signaling. Interestingly, therapeutic manipulation of the cGAS-STING pathway has yielded inconsistent and even contradictory effects on different liver diseases due to the distinct physiological characteristics of intrahepatic cells that express and respond to STING. In this review, we comprehensively summarize recent advancements in understanding the dual roles of the STING pathway, highlighting that the benefits of targeting STING signaling depend on the specific types of target cells and stages of liver injury. Additionally, we offer a novel perspective on the suitability of STING agonists and antagonists for clinical assessment. In conclusion, STING signaling remains a highly promising therapeutic target, and the development of STING pathway modulators holds great potential for the treatment of liver diseases.

Guanylate-Binding Protein 1 (GBP1) Enhances IFN-α Mediated Antiviral Activity against Hepatitis B Virus Infection

Interferon-alpha (IFN-α) is a first-line drug for treating chronic hepatitis B (CHB). Guanylate-binding protein 1 (GBP1) is one of the interferon-stimulating factors, which participates in the innate immunity of the host and plays an antiviral and antibacterial role. In this study, we explored how GBP1 is involved in IFN-α antiviral activity against HBV. Before being gathered, HepG2-NTCP and HepG2 2.15 cells were transfected with the wild-type hGBP1 plasmid or si-GBP1, respectively, and followed by stimulation with Peg-IFNα-2b. We systematically explored the role of GBP1 in regulating HBV infection in cell models. Additionally, we also examined GBP1 levels in CHB patients. GBP1 activity increased, and its half-life was prolonged after HBV infection. Overexpression of GBP1 inhibited the production of HBsAg and HBeAg, as well as HBs protein and HBV total RNA levels, whereas silencing of GBP1 inhibited its ability to block viral infections. Interestingly, overexpressing GBP1 co-treatment with Peg-IFNα-2b further increased the antiviral effect of IFN-α, while GBP1 silencing co-treatment with Peg-IFNα-2b partly restored its inhibitory effect on HBV. Mechanistically, GBP1 mediates the anti-HBV response of Peg-IFNα-2b by targeting HBs. Analysis of clinical samples revealed that GBP1 was elevated in CHB patients and increased with Peg-IFNα-2b treatment, while GBP1 showed good stability in the interferon response group. Our study demonstrates that GBP1 inhibits HBV replication and promotes HBsAg clearance. It is possible to achieve antiviral effects through the regulation of IFN-α induced immune responses in response to HBV.

KLRG1-expressing CD8+ T cells are exhausted and polyfunctional in patients with chronic hepatitis B

Killer cell lectin-like receptor G1 (KLRG1) has traditionally been regarded as an inhibitory receptor of T cell exhaustion in chronic infection and inflammation. However, its exact role in hepatitis B virus (HBV) infection remains elusive. CD8+ T cells from 190 patients with chronic hepatitis B were analyzed ex vivo for checkpoint and apoptosis markers, transcription factors, cytokines and subtypes in 190 patients with chronic hepatitis B. KLRG1+ and KLRG1- CD8+ T cells were sorted for transcriptome analysis. The impact of the KLRG1-E-cadherin pathway on the suppression of HBV replication mediated by virus-specific T cells was validated in vitro. As expected, HBV-specific CD8+ T cells expressed higher levels of KLRG1 and showed an exhausted molecular phenotype and function. However, despite being enriched for the inhibitory molecules, thymocyte selection-associated high mobility group box protein (TOX), eomesodermin (EOMES), and Helios, CD8+ T cells expressing KLRG1 produced significant levels of tumour necrosis factor (TNF)-α, interferon (IFN)-γ, perforin, and granzyme B, demonstrating not exhausted but active function. Consistent with the in vitro phenotypic assay results, RNA sequencing (RNA-seq) data showed that signature effector T cell and exhausted T cell genes were enriched in KLRG1+ CD8+ T cells. Furthermore, in vitro testing confirmed that KLRG1-E-cadherin binding inhibits the antiviral efficacy of HBV-specific CD8+ T cells. Based on these findings, we concluded that KLRG1+ CD8+ T cells are not only a terminally exhausted subgroup but also exhibit functional diversity, despite inhibitory signs in HBV infection.

Perioperative remedial antiviral therapy in hepatitis B virus-related hepatocellular carcinoma resection: How to achieve a better outcome

BACKGROUND

Although the benefits of antiviral therapy for hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) have been proven, researchers have not confirmed the differences in patient outcomes between patients who received preoperative antiviral therapy for a period of time (at least 24 wk) and patients who received remedial antiviral therapy just before radical resection for HBV-related HCC.

AIM

To investigate the efficacy of perioperative remedial antiviral therapy in patients with HBV-related HCC.

METHODS

A retrospective study of patients who underwent radical resection for HBV-related HCC at the First Affiliated Hospital of Xi'an Jiaotong University from January 2016 to June 2019 was conducted. Considering the history of antiviral therapy, patients were assigned to remedial antiviral therapy and preoperative antiviral therapy groups.

RESULTS

Kaplan-Meier analysis revealed significant differences in overall survival (P < 0.0001) and disease-free survival (P = 0.035) between the two groups. Multivariate analysis demonstrated that a history of preoperative antiviral treatment was independently related to improved survival (hazard ratio = 0.27; 95% confidence interval: 0.08-0.88; P = 0.030).

CONCLUSION

In patients with HBV-related HCC, it is ideal to receive preoperative long-term antiviral therapy, which helps patients tolerate more extensive hepatectomy; however, remedial antiviral therapy, which reduces preoperative HBV-DNA levels to less than 4 Log10 copies DNA/mL, can also result in improved outcomes.

Model-based meta-analysis to quantify the effects of short interfering RNA therapeutics on hepatitis B surface antigen turnover in hepatitis B-infected mice

The objective of this study was to compare the efficacy of short interfering RNA therapeutics (siRNAs) in reducing hepatitis B surface antigen (HBsAg) levels in hepatitis B-infected (HBV) mice across multiple siRNA therapeutic classes using model-based meta-analysis (MBMA) techniques. Literature data from 10 studies in HBV-infected mice were pooled, including 13 siRNAs, formulated as liposomal nanoparticles (LNPs) or conjugated to either cholesterol (chol) or N-acetylgalactosamine (GalNAc). Time course of the baseline- and placebo-corrected mean HBsAg profiles were modeled using kinetics of drug effect (KPD) model coupled to an indirect response model (IRM) within a longitudinal non-linear mixed-effects MBMA framework. Single and multiple dose simulations were performed exploring the role of dosing regimens across evaluated siRNA classes. The HBsAg degradation rate (0.72 day-1) was consistent across siRNAs but exhibited a large between-study variability of 31.4% (CV%). The siRNA biophase half-life was dependent on the siRNA class and was highest for GalNAc-siRNAs (21.06 days) and lowest for chol-siRNAs (2.89 days). ID50 estimates were compound-specific and were lowest for chol-siRNAs and highest for GalNAc-siRNAs. Multiple dose simulations suggest GalNAc-siRNAs may require between 4 and 7 times less frequent dosing at higher absolute dose levels compared to LNP-siRNAs and chol-siRNAs, respectively, to reach equipotent HBsAg-lowering effects in HBV mice. In conclusion, non-clinical HBsAg concentration-time data after siRNA administration can be described using the presented KPD-IRM MBMA framework. This framework allows to quantitatively compare the effects of siRNAs on the HBsAg time course and inform dose and regimen selection across siRNA classes. These results may support siRNA development, optimize preclinical study designs, and inform data analysis methodology of future anti-HBV siRNAs; and ultimately, support siRNA model-informed drug development (MIDD) strategies.

Spatial transcriptomics reveals a low extent of transcriptionally active hepatitis B virus integration in patients with HBsAg loss

OBJECTIVE

Hepatitis B virus (HBV) can integrate into the chromosomes of infected hepatocytes, contributing to the production of hepatitis B surface antigen (HBsAg) and to hepatocarcinogenesis. In this study, we aimed to explore whether transcriptionally active HBV integration events spread throughout the liver tissue in different phases of chronic HBV infection, especially in patients with HBsAg loss.

DESIGN

We constructed high-resolution spatial transcriptomes of liver biopsies containing 13 059 tissue spots from 18 patients with chronic HBV infection to analyse the occurrence and relative distribution of transcriptionally active viral integration events. Immunohistochemistry was performed to evaluate the expression of HBsAg and HBV core antigen. Intrahepatic covalently closed circular DNA (cccDNA) levels were quantified by real-time qPCR.

RESULTS

Spatial transcriptome sequencing identified the presence of 13 154 virus-host chimeric reads in 7.86% (1026 of 13 059) of liver tissue spots in all patients, including three patients with HBsAg loss. These HBV integration sites were randomly distributed on chromosomes and can localise in host genes involved in hepatocarcinogenesis, such as ALB, CLU and APOB. Patients who were receiving or had received antiviral treatment had a significantly lower percentage of viral integration-containing spots and significantly fewer chimeric reads than treatment-naïve patients. Intrahepatic cccDNA levels correlated well with viral integration events.

CONCLUSION

Transcriptionally active HBV integration occurred in chronically HBV-infected patients at different phases, including in patients with HBsAg loss. Antiviral treatment was associated with a decreased number and extent of transcriptionally active viral integrations, implying that early treatment intervention may further reduce the number of viral integration events.

Functional cure is associated with younger age in children undergoing antiviral treatment for active chronic hepatitis B

BACKGROUND AND AIMS

Functional cure is difficult to achieve using current antiviral therapies; moreover, limited data are available regarding treatment outcomes in children. This retrospective study aimed to assess the frequency of functional cure among children undergoing antiviral treatment for active chronic hepatitis B (CHB).

METHODS

A total of 372 children aged 1-16 years, with active CHB were enrolled and underwent either nucleos(t)ide analog monotherapy or combination therapy with interferon-α (IFN-α) for 24-36 months. All children attended follow-up visits every 3 months. Functional cure was defined as evidence of hepatitis B virus (HBV) DNA loss, circulating hepatitis B e antigen (HBeAg) loss/seroconversion, and hepatitis B surface antigen (HBsAg) loss.

RESULTS

After 36 months of antiviral treatment and/or follow-up visits, children with CHB aged 1- < 7 years exhibited higher rates of HBV DNA clearance, HBeAg seroconversion, and HBsAg loss than CHB children ≥ 7-16 years of age (93.75% versus [vs.] 86.21% [p < 0.0001]; 79.30% vs. 51.72% [p < 0.0001]; and 50.78% vs. 12.93% [p < 0.0001], respectively). Longitudinal investigation revealed more rapid dynamic reduction in HBV DNA, HBeAg, and HBsAg levels in children aged 1-7 years than in those aged ≥ 7-16 years with CHB. According to further age-stratified analysis, HBsAg loss rates were successively decreased in children with CHB who were 1- < 3, 3- < 7, 7- < 12, and 12-16 years of age (62.61% vs. 41.13% vs. 25.45% vs. 1.64%, respectively; p < 0.0001) at 36 months. In addition, baseline HBsAg level < 1,500 IU/mL was found to favor disease cure among these pediatric patients. No serious adverse events were observed throughout the study period.

CONCLUSION

Results of the present study demonstrated that children aged 1- < 7 years, with active CHB can achieve a high functional cure rate by undergoing antiviral therapy compared to those aged ≥ 7 years, who undergo antiviral therapy. These data support the use of antiviral treatment at an early age in children with CHB. However, future prospectively randomized controlled trials are necessary to validate the findings of this study.

Longterm Outcome of Therapeutic Vaccination with a Third Generation Pre-S/S HBV Vaccine (PreHevbrioR) of Chronically HBV Infected Patients

Several antiviral treatment regimens for chronic hepatitis B (CHB) virus infection have been shown to be effective in suppressing viral load and reducing the risk of hepatocellular injury and its complications. It has been hypothesized that high levels of circulating HBV surface antigen(s) may lead to immune tolerance against HBV and contribute to chronic carriership. Conversely, low-level HBsAg may create a window for the reconstitution of an HBV-specific immune response through vaccination and control of infection. Previous studies in non-responders to yeast-derived HBV vaccines, using a third-generation pre-S/S vaccine, have led to up to 95% anti-HBs seroconversion. This report evaluates the long-term outcome after experimental vaccination with a pre-S/S HBV vaccine intended as a therapeutic intervention in chronic HBV carriers. Four low-level HBsAg carriers (<500 IU/mL) were vaccinated three to seven times with 20 μg PreHevbrioR. Three out of four carriers eliminated HBsAg completely and seroconverted to anti-HBs. One patient seroconverted to anti-HBs but remained with a borderline HBsAg titer (10 IU/mL). Serum anti-HBs levels following repeated vaccination varied between 27 and >1000 IU/L, respectively. Long-term observation (>6 years) showed that after discontinuing NUC treatment for at least two years, HBsAg and HBV DNA remained negative with anti-HBs positive titers ranging between 80 and >1000 IU/L. Based on our preliminary observations, there is a rationale to further evaluate the role of this vaccine as a therapeutic agent.

Risk of HBV reactivation in HCC patients undergoing combination therapy of PD-1 inhibitors and angiogenesis inhibitors in the antiviral era

BACKGROUND

Although routine antiviral therapy has been implemented in HCC patients, the risk of HBV reactivation (HBVr) remains with the use of programmed cell death-1(PD-1) blockade-based combination immunotherapy and the relevant risk factors are also unclear. Therefore, we aimed to identify the incidence and risk factors of HBVr in HCC patients undergoing combination therapy of PD-1 inhibitors and angiogenesis inhibitors and concurrent first-line antivirals.

METHODS

We included a total of 218 HBV-related HCC patients with first-line antivirals who received PD-1 inhibitors alone or together with angiogenesis inhibitors. According to the anti-tumor therapy modalities, patients were divided into PD-1 inhibitors monotherapy group (anti-PD-1 group) and combination therapy group (anti-PD-1 plus angiogenesis inhibitors group). The primary study endpoint was the incidence of HBVr.

RESULTS

HBVr occurred in 16 (7.3%) of the 218 patients, 2 cases were found in the anti-PD-1 group and the remaining 14 cases were in the combination group. The Cox proportional hazard model identified 2 independent risk factors for HBVr: combination therapy (hazard ratio [HR], 4.608, 95%CI 1.010-21.016, P = 0.048) and hepatitis B e antigen (HBeAg) positive (HR, 3.695, 95%CI 1.246-10.957, P = 0.018). Based on the above results, we developed a simple risk-scoring system and found that the high-risk group (score = 2) developed HBVr more frequently than the low-risk group (score = 0) (Odds ratio [OR], 17.000, 95%CI 1.946-148.526, P = 0.01). The area under the ROC curve (AUC-ROC) was 7.06 (95%CI 0.581-0.831, P = 0.006).

CONCLUSION

HBeAg-positive patients receiving combination therapy have a 17-fold higher risk of HBVr than HBeAg-negative patients with PD-1 inhibitors monotherapy.

Hypermethylation of the glutathione peroxidase 4 gene promoter is associated with the occurrence of immune tolerance phase in chronic hepatitis B

BACKGROUND

Hepatitis B virus (HBV) infection is a public health problem that seriously threatens human health. This study aimed to investigate the clinical significance of glutathione peroxidase 4(GPX4) in the occurrence and development of chronic hepatitis B (CHB).

METHODS

A total of 169 participants including 137 patients with CHB and 32 healthy controls (HCs) were recruited. We detected the expression of GPX4 and stimulator of interferon genes (STING) in peripheral blood mononuclear cells (PBMCs) by real-time quantitative polymerase chain reaction (RT-qPCR). The methylation level of GPX4 gene promoter in PBMCs was detected by TaqMan probe-based quantitative methylation-specific PCR (MethyLight). Enzyme-linked immunosorbent assay (ELISA) was performed to detect the serum levels of GPX4, IFN-β, oxidative stress (OS) related molecules, and pro-inflammatory cytokines.

RESULTS

The expression levels of GPX4 in PBMCs and serum of CHB patients were lower than those of HCs, but the methylation levels of GPX4 promoter were higher than those of HCs, especially in patients at the immune tolerance phase. STING mRNA expression levels in PBMCs and serum IFN-β levels of patients at the immune activation phase and reactivation phase of CHB were higher than those at other clinical phases of CHB and HCs. GPX4 mRNA expression level and methylation level in PBMCs from patients with CHB had a certain correlation with STING and IFN-β expression levels. In addition, the methylation level of the GPX4 promoter in PBMCs from patients with CHB was correlated with molecules associated with OS and inflammation.

CONCLUSIONS

GPX4 may play an important role in the pathogenesis and immune tolerance of CHB, which may provide new ideas for the functional cure of CHB.

In Vitro Lactic Acid Bacteria Anti-Hepatitis B Virus (HBV) Effect and Modulation of the Intestinal Microbiota in Fecal Cultures from HBV-Associated Hepatocellular Carcinoma Patients

Hepatocellular carcinoma (HCC), being ranked as the top fifth most prevalent cancer globally, poses a significant health challenge, with a considerable mortality rate. Hepatitis B virus (HBV) infection stands as the primary factor contributing to HCC, presenting substantial challenges in its treatment. This study aimed to identify lactic acid bacteria (LAB) with anti-HBV properties and evaluate their impact on the intestinal flora in HBV-associated HCC. Initially, two LAB strains, Levilactobacillus brevis SR52-2 (L. brevis SR52-2) and LeviLactobacillus delbrueckii subsp. bulgaicus Q80 (L. delbrueckii Q80), exhibiting anti-HBV effects, were screened in vitro from a pool of 498 LAB strains through cell experiments, with extracellular expression levels of 0.58 ± 0.05 and 0.65 ± 0.03, respectively. These strains exhibited the capability of inhibiting the expression of HBeAg and HBsAg. Subsequent in vitro fermentation, conducted under simulated anaerobic conditions mimicking the colon environment, revealed a decrease in pH levels in both the health control (HC) and HCC groups influenced by LAB, with a more pronounced effect observed in the HC group. Additionally, the density of total short-chain fatty acids (SCFAs) significantly increased (p < 0.05) in the HCC group. Analysis of 16S rRNA highlighted differences in the gut microbiota (GM) community structure in cultures treated with L. brevis SR52-2 and L. delbrueckii Q80. Fecal microflora in normal samples exhibited greater diversity compared to HBV-HCC samples. The HCC group treated with LAB showed a significant increase in the abundance of the phyla Firmicutes, Bacteroidetes and Actinobacteria, while Proteobacteria significantly decreased compared to the untreated HCC group after 48 h. In conclusion, the findings indicate that LAB, specifically L. brevis SR52-2 and L. delbrueckii Q80, possessing antiviral properties, contribute to an improvement in gastrointestinal health.

Preclinical Antiviral and Safety Profiling of the HBV RNA Destabilizer AB-161

HBV RNA destabilizers are a class of small-molecule compounds that target the noncanonical poly(A) RNA polymerases PAPD5 and PAPD7, resulting in HBV RNA degradation and the suppression of viral proteins including the hepatitis B surface antigen (HBsAg). AB-161 is a next-generation HBV RNA destabilizer with potent antiviral activity, inhibiting HBsAg expressed from cccDNA and integrated HBV DNA in HBV cell-based models. AB-161 exhibits broad HBV genotype coverage, maintains activity against variants resistant to nucleoside analogs, and shows additive effects on HBV replication when combined with other classes of HBV inhibitors. In AAV-HBV-transduced mice, the dose-dependent reduction of HBsAg correlated with concentrations of AB-161 in the liver reaching above its effective concentration mediating 90% inhibition (EC90), compared to concentrations in plasma which were substantially below its EC90, indicating that high liver exposure drives antiviral activities. In preclinical 13-week safety studies, minor non-adverse delays in sensory nerve conductance velocity were noted in the high-dose groups in rats and dogs. However, all nerve conduction metrics remained within physiologically normal ranges, with no neurobehavioral or histopathological findings. Despite the improved neurotoxicity profile, microscopic findings associated with male reproductive toxicity were detected in dogs, which subsequently led to the discontinuation of AB-161's clinical development.

Long-Term Outcomes after Switching to Tenofovir Alafenamide in Patients with Chronic Hepatitis B

We sought to determine the long-term outcomes of chronic hepatitis B (CHB) cases switching to tenofovir alafenamide (TAF, n = 104, median age = 63.5 years). Data at switching to TAF (baseline) and those at 1, 2, 3, 4, and 5 years from switching to TAF were compared. At baseline, HB envelop antigen (HBeAg) seropositivity was found in 20 patients (19.2%), and undetectable HBV-DNA in 77 patients (74.0%). Percentage of detectable HBV-DNA significantly reduced at any time point. HB surface antigen (HBsAg) levels significantly reduced at 3, 4, and 5 years. The percentage of HBeAg seropositivity significantly reduced at 5 years. HB core related antigen levels did not significantly change. In patients with baseline HbeAg seropositivity, HbsAg levels significantly reduced at any time point, and a similar trend was found in patients without HBeAg seropositivity. In patients with baseline FIB4 index >1.85, HBsAg levels significantly reduced at 3, 4, and 5 years, and in patients with baseline FIB4 index <1.85, HBsAg levels significantly reduced at any time point. The estimated glomerular filtration rate significantly reduced only at 5 years. The discontinuation rate owing to the side effects of TAF was 0%. In conclusion, switching to TAF therapy in patients with CHB may be effective and safe at least up to 5 years.

Adeno-associated viruses for gene therapy - clinical implications and liver-related complications, a guide for hepatologists

Gene therapy has garnered increasing interest over recent decades. Several therapies employing gene transfer mechanisms have been developed, and, of these, adeno-associated virus (AAV) vectors have demonstrated viability for use with in vivo gene therapy. Several AAV-based therapeutics have received regulatory approval in the last few years including those for retinal disease, spinal muscular atrophy or aromatic L-amino acid decarboxylase deficiency. Lately, with the introduction of novel liver-directed AAV vector-based therapeutics for the treatment of haemophilia A and B, gene therapy has attracted significant attention in the hepatology community, with the liver increasingly recognised as a target for gene therapy. However, the introduction of foreign DNA into hepatocytes is associated with a risk of hepatic reactions, with raised ALT (alanine aminotransferase) and AST (aspartate aminotransferase) being - so far - the most commonly reported side effects. The complete mechanisms underlying the ALT flairs remain to be determined and the long-term risks associated with these new treatments is not yet known. The liver community is increasingly being asked to support liver-directed gene therapy to mitigate potential liver associated harm. In this review, we focus on AAV vector-based gene therapy, shedding light on this promising technique and its remarkable success in haemophilia, with a special focus on hepatic complications and their management in daily clinical practice.

HBV promotes its replication by up-regulating RAD51C gene expression

Chronic hepatitis B virus (HBV) infection is a major cause of hepatocellular carcinoma (HCC), pegylated-interferon-α(PEG-IFNα) and long-term nucleos(t)ide analogs (NUCs) are mainly drugs used to treat HBV infection, but the effectiveness is unsatisfactory in different populations, the exploration of novel therapeutic approaches is necessary. RAD51C is associated with DNA damage repair and plays an important role in the development and progression of tumors. Early cDNA microarray results showed that RAD51C expression was significantly increased in HBV-infected HCC cells, however, the relationship between HBV infection and abnormal expression of RAD51C has not been reported. Therefore, we conducted RT-PCR, western blot, Co-immunoprecipitation(Co-IP), and immunofluorescence(IF) to detect HBV-RAD51C interaction in RAD51C overexpression or interfering HCC cells. Our results showed that RAD51C and HBV X protein(HBX) produced a direct interaction in the nucleus, the HBV infection of HCC cells promoted RAD51C expression, and the increased expression of RAD51C promoted HBV replication. This indicated that RAD51C is closely related to the occurrence and development of HCC caused by HBV infection, and may bring a breakthrough in the the prevention and treatment study of HCC.

Interferon lambda receptor-1 isoforms differentially influence gene expression and HBV replication in stem cell-derived hepatocytes

BACKGROUND

In the tolerogenic liver, inadequate or ineffective interferon signaling fails to clear chronic HBV infection. Lambda IFNs (IFNL) bind the interferon lambda receptor-1 (IFNLR1) which dimerizes with IL10RB to induce transcription of antiviral interferon-stimulated genes (ISG). IFNLR1 is expressed on hepatocytes, but low expression may limit the strength and antiviral efficacy of IFNL signaling. Three IFNLR1 transcriptional variants are detected in hepatocytes whose role in regulation of IFNL signaling is unclear: a full-length and signaling-capable form (isoform 1), a form that lacks a portion of the intracellular JAK1 binding domain (isoform 2), and a secreted form (isoform 3), the latter two predicted to be signaling defective. We hypothesized that altering expression of IFNLR1 isoforms would differentially impact the hepatocellular response to IFNLs and HBV replication.

METHODS

Induced pluripotent stem-cell derived hepatocytes (iHeps) engineered to contain FLAG-tagged, doxycycline-inducible IFNLR1 isoform constructs were HBV-infected then treated with IFNL3 followed by assessment of gene expression, HBV replication, and cellular viability.

RESULTS

Minimal overexpression of IFNLR1 isoform 1 markedly augmented ISG expression, induced de novo proinflammatory gene expression, and enhanced inhibition of HBV replication after IFNL treatment without adversely affecting cell viability. In contrast, overexpression of IFNLR1 isoform 2 or 3 partially augmented IFNL-induced ISG expression but did not support proinflammatory gene expression and minimally impacted HBV replication.

CONCLUSIONS

IFNLR1 isoforms differentially influence IFNL-induced gene expression and HBV replication in hepatocytes. Regulated IFNLR1 expression in vivo could limit the capacity of this pathway to counteract HBV replication.

Higher TP53BP2 expression is associated with HBsAg loss in peginterferon-α-treated patients with chronic hepatitis B

BACKGROUND & AIMS

HBsAg loss is only observed in a small proportion of patients with chronic hepatitis B (CHB) who undergo interferon treatment. Investigating the host factors crucial for functional cure of CHB can aid in identifying individuals who would benefit from peginterferon-α (Peg-IFNα) therapy.

METHODS

We conducted a genome-wide association study (GWAS) by enrolling 48 patients with CHB who achieved HBsAg loss after Peg-IFNα treatment and 47 patients who didn't. In the validation stage, we included 224 patients, of whom 90 had achieved HBsAg loss, to validate the identified significant single nucleotide polymorphisms. To verify the functional involvement of the candidate genes identified, we performed a series of in vitro and in vivo experiments.

RESULTS

GWAS results indicated a significant association between the rs7519753 C allele and serum HBsAg loss in patients with CHB after Peg-IFNα treatment (p = 4.85 × 10-8, odds ratio = 14.47). This association was also observed in two independent validation cohorts. Expression quantitative trait locus analysis revealed higher hepatic TP53BP2 expression in individuals carrying the rs7519753 C allele (p = 2.90 × 10-6). RNA-sequencing of liver biopsies from patients with CHB after Peg-IFNα treatment revealed that hepatic TP53BP2 levels were significantly higher in the HBsAg loss group compared to the HBsAg persistence group (p = 0.035). In vitro and in vivo experiments demonstrated that loss of TP53BP2 decreased interferon-stimulated gene levels and the anti-HBV effect of IFN-α. Mechanistically, TP53BP2 was found to downregulate SOCS2, thereby facilitating JAK/STAT signaling.

CONCLUSION

The rs7519753 C allele is associated with elevated hepatic TP53BP2 expression and an increased probability of serum HBsAg loss post-Peg-IFNα treatment in patients with CHB. TP53BP2 enhances the response of the hepatocyte to IFN-α by suppressing SOCS2 expression.

IMPACT AND IMPLICATIONS

Chronic hepatitis B (CHB) remains a global public health issue. Although current antiviral therapies are more effective in halting disease progression, only a few patients achieve functional cure for hepatitis B with HBsAg loss, highlighting the urgent need for a cure for CHB. This study revealed that the rs7519753 C allele, which is associated with high expression of hepatic TP53BP2, significantly increases the likelihood of serum HBsAg loss in patients with CHB undergoing Peg-IFNα treatment. This finding not only provides a promising predictor for HBsAg loss but identifies a potential therapeutic target for Peg-IFNα treatment. We believe our results are of great interest to a wide range of stakeholders based on their potential clinical implications.

Novel Approaches to Inhibition of HBsAg Expression from cccDNA and Chromosomal Integrants: A Review

Hepatitis B virus (HBV) is a widely prevalent liver infection that can cause acute or chronic hepatitis. Although current treatment modalities are highly effective in the suppression of viral levels, they cannot eliminate the virus or achieve definitive cure. This is a consequence of the complex nature of HBV-host interactions. Major challenges to achieving sustained viral suppression include the presence of a high viral burden from the HBV DNA and hepatitis B surface antigen (HBsAg), the presence of reservoirs for HBV replication and antigen production, and the HBV-impaired innate and adaptive immune response of the host. Those therapeutic methods include cell entry inhibitors, HBsAg inhibitors, gene editing approaches, immune-targeting therapies and direct inhibitors of covalently closed circular DNA (cccDNA). Novel approaches that target these key mechanisms are now being studied in preclinical and clinical phases. In this review article, we provide a comprehensive review on mechanisms by which HBV escapes elimination from current treatments, and highlight new agents to achieve a definitive HBV cure.

Efficacy of pegylated interferon α-2b plus entecavir therapy and predictors of treatment success in children with chronic hepatitis B

Introduction

Interferon therapy, used in the treatment of chronic hepatitis B (CHB), is one of the means by which patients can achieve a functional cure. Pegylated interferon is currently used in the treatment of CHB. There are two main types of pegylated interferon: α-2b and α-2a.

Methods

This study explored the efficacy, safety, and predictors of treatment response for α-2b plus entecavir among children in a real-world setting.

Results

The study included 76 patients aged 3-18 years, all of whom were treated with interferon α-2b plus entecavir. The mean duration of treatment was 401.99 days, and 31.6% (24/76) of patients achieved HBsAg clearance. Competing risk model analyses showed that children with baseline HBsAg <1500 IU/mL (subdistribution hazard ratio [sHR]=2.643, P=0.022) and a higher baseline alanine aminotransferase (ALT) level (sHR=1.005, P=0.000) had a higher probability of achieving HBsAg clearance during treatment. Conversely, children with a higher hepatitis B virus loading level (sHR=0.835, P=0.043) and age ≥10 years (sHR=0.243, P=0.002) had a lower probability of achieving HBsAg clearance during treatment. A decrease of >1 log10 in HBsAg level (sHR=3.479, P=0.001) at 12 weeks of treatment was associated with a higher probability of achieving surface antigen clearance.

Discussion

These results indicated that interferon plus entecavir therapy is a promising means of achieving HBsAg clearance in children with CHB. Moreover, HBsAg, ALT, virus loading, and age are indicators of treatment success probability.

Desmethoxycurcumin aids IFNα's anti-HBV activity by antagonising CRYAB reduction and stabilising IFNAR1 protein

The eradication of chronic hepatitis B (CHB) caused by hepatitis B virus (HBV) infection is a crucial goal in clinical practice. Enhancing the anti-HBV activity of interferon type I (IFNI) is a key strategy for achieving a functional cure for CHB. In this study, we investigated the effect of combined treatment with IFNα and Desmethoxycurcumin (DMC) on HBV replication in HepG2 cells and explored the underlying mechanism. Our results indicated IFNα alone was ineffective in completely inhibiting HBV replication, which was attributed to the virus-induced down-regulation of IFNI receptor 1 (IFNAR1) protein. However, the addition of a low dose of DMC significantly synergized with IFNα, leading to notable enhancement of IFNα anti-HBV activity. This effect was achieved by stabilising the IFNAR1 protein. Further investigation revealed that low dose DMC effectively blocked the ubiquitination-mediated degradation of IFNAR1, which was accomplished by rescuing the protein levels of alphaB-crystallin (CRYAB) and orchestrating the interaction between CRYAB and the E3 ubiquitin ligase, β-Trcp. Importantly, over-expression of CRYAB was found to favour the antiviral activity of IFNα against HBV replication. In conclusion, our study demonstrates that low-dose DMC enhanced the anti-HBV activity of IFNα by counteracting the reduction of CRYAB and stabilising the IFNAR1 protein.

Patient acceptability of, and attitudes towards, hepatitis B cure research - A scoping review and identification of knowledge gaps

Functional cure, defined as durable loss of hepatitis B surface antigen (HBsAg) and hepatitis B virus (HBV) DNA suppression off therapy, is an increasingly important goal in the treatment of chronic hepatitis B. Although novel treatments aimed at achieving functional cure are being developed and tested in clinical trials, it is important to assess the perspectives of people living with HBV towards these potential treatments and their participation in HBV functional cure research. We have performed a scoping review that revealed that there is limited knowledge regarding patient perspectives of HBV functional cure research and then identified gaps in knowledge for further investigation. Our work highlights the need for further studies in patient perspectives in HBV functional cure research.

Association of Alanine Aminotransferase Flares to Hepatitis B Surface Decline During Tenofovir Alone or With Pegylated Interferon Alfa

INTRODUCTION

We aimed to determine whether the intensity of alanine aminotransferase (ALT) flares during antiviral therapy is associated with the level of hepatitis B surface antigen (HBsAg) decline.

METHODS

Quantitative HBsAg was determined during tenofovir monotherapy or tenofovir plus peginterferon alfa-2a in 201 participants with hepatitis B e antigen-positive or -negative chronic hepatitis B. A multivariable analysis identified factors associated with a shorter time to reduction in HBsAg.

RESULTS

Fifty flares occurred during treatment of which 74% were moderate (ALT >5-10 × upper limit of normal) or severe (ALT >10 × upper limit of normal). These flares were associated with greater HBsAg decline compared with no flares. Significantly faster times to HBsAg decline >1 log 10 IU ( P = 0.04) and to HBsAg level <100 IU/mL ( P = 0.01) were observed with severe flares.

DISCUSSIONS

Flare severity is a potentially important factor associated with shorter time to HBsAg reduction. These findings can be useful when evaluating HBsAg response to evolving hepatitis B virus therapies.

Editorial: Time to consider early treatment for chronic hepatitis B in both children and adults-authors' reply

This article is linked to Wu et al papers. To view these articles, visit https://doi.org/10.1111/apt.17667 and https://doi.org/10.1111/apt.17679