Hepatitis B surface antigen seroclearance during chronic HBV infection

Rate and durability of the clearance of HBsAg in Alaska Native persons with long-term HBV infection: 1982-2019

BACKGROUND AND AIMS

A functional cure and therapeutic end point of chronic HBV infection is defined as the clearance of HBsAg from serum. Little is known about the long-term durability of HBsAg loss in the Alaskan Native population.

APPROACH AND RESULTS

We performed a retrospective cohort study of Alaska Native patients with chronic HBV-monoinfection from January 1982 through December 2019. The original group in this cohort was identified during a 1982 to 1987 population-based screening for 3 HBV serologic markers in 53,000 Alaska Native persons. With close to 32,000 years of follow-up, we assessed the frequency and duration of HBsAg seroclearance (HBsAg-negative for > 6 mo). We examined factors associated with HBsAg clearance and followed persons for a median of 13.1 years afterward to assess the durability of HBsAg clearance. Among 1079 persons with an average length of follow-up of 33 years, 260 (24%) cleared HBsAg at a constant rate of 0.82% per person/per year. Of the 260 persons who cleared, 249 (96%) remained HBsAg-negative, while 11 persons had ≥ 2 transient HBsAg-positive results in subsequent follow-up.

CONCLUSIONS

Of the patients with chronic HBV monoinfection, 0.82% of people per year achieved a functional cure. HBsAg seroclearance was durable for treated and nontreated patients and lasted, on average, over 13 years without seroreversion.

Hepatitis B surface antigen (HBsAg) glycan isomer is predictive of HBsAg seroclearance in patients with chronic hepatitis B

AIM

Measurement of O-glycosylated middle hepatitis B surface antigen (HBsAg glycan isomer, HBsAgGi) has been developed to quantify hepatitis B virus (HBV) infectious virions and distinguish them from subviral particles. This study aimed to evaluate the association between serum HBsAg seroclearance and serum HBV virions measured by HBsAgGi in patients with chronic hepatitis B (CHB).

METHODS

Serum HBsAgGi levels were quantified in 232 treatment-naïve patients with CHB genotype C. Cox proportional hazards analysis was used to calculate hazard ratios (HRs) for factors associated with HBsAg seroclearance.

RESULTS

Baseline HBsAgGi levels showed significant differences among HBV phenotypes. During a median follow-up period of 7.4 years, 22 of the 232 patients achieved HBsAg seroclearance. Multivariate analysis demonstrated that quantitative HBsAg, nucleoside/nucleotide analog therapy during the follow-up period, and HBsAgGi levels were independent predictors of seroclearance. The adjusted HR indicated that the HBsAg seroclearance probability in patients with low HBsAgGi (≤3.5log ng/mL) was over five times higher than that in patients with high HBsAgGi. Kaplan-Meier analysis indicated that the 10-year probabilities of HBsAg seroclearance were 21.0% and 3.0% in patients with low and high HBsAgGi levels, respectively (p < 0.001), and that patients with high HBsAgGi levels showed low seroclearance probabilities irrespective of the other predictors.

CONCLUSION

Serum HBV infectious virion levels, measured using HBsAgGi, may be a novel predictor of HBsAg seroclearance.

Advances in discovery of novel investigational agents for functional cure of chronic hepatitis B: A comprehensive review of phases II and III therapeutic agents

Chronic hepatitis B virus (HBV) infection affects over 295 million people globally and an estimated 1.6 million people in the United States. It is associated with significant morbidity and mortality due to cirrhosis, liver failure, and liver cancer. Antiviral therapy with oral nucleos(t)ide analogues is associated with high rates of virologic suppression, which in turn has been associated with a decreased risk of liver complications. However, current antiviral regimens are limited by concerns with adverse effects, adherence, resistance, long-term treatment, and ongoing risk for liver events. Novel investigational agents are currently in development and are targeted at achieving functional cure with sustained hepatitis B surface antigen (HBsAg) loss and suppression of HBV DNA. Herein we review key evidence from phases II and III trials defining the efficacy and safety profiles for key investigational agents for functional cure of chronic hepatitis B, including core/capsid inhibitors, entry inhibitors, RNA interference (siRNA/ASO), HBsAg inhibitors, Toll-like receptor agonists, checkpoint inhibitors, and therapeutic vaccines.

Long-Term HBsAg Titer Kinetics with Entecavir/Tenofovir: Implications for Predicting Functional Cure and Low Levels

The long-term kinetics of quantitative HBsAg levels in HBV-infected patients treated with entecavir or tenofovir, as well as the role of quantitative HBsAg in predicting functional cure (HBsAg loss) and low HBsAg levels (<2 log IU/mL) remain unclear. Of some 1661 consecutively enrolled patients newly treated with entecavir or tenofovir, we analyzed 852 patients who underwent serial HBsAg level checks every 6-12 months. The primary outcomes included long-term kinetics in HBsAg levels and the rate of functional cure and achieving low HBsAg levels. Over a mean 6.3-year follow-up, the functional cure rate was 2.28% (n = 19), and 12.9% (n = 108) achieved low HBsAg levels. A significant HBsAg level reduction was seen in the first treatment year (p < 0.05), with another stepwise decrease between year 6-7. These trends were pronounced in patients with chronic hepatitis and HBeAg-positivity compared to those with cirrhosis and HBeAg-negativity, respectively. Baseline HBsAg of ≤3 log IU/mL and the first-year HBsAg reduction were key predictors for both functional cure and low HBsAg levels (p < 0.05). In conclusion, our findings elucidate the stepwise reduction in quantitative HBsAg dynamics during high-potency NA therapy (entecavir or tenofovir) along with variations based on different conditions. We also underscore the significance of quantitative HBsAg titer in predicting functional cure and low-HBsAg levels.

Evaluate the clinical efficacy of traditional Chinese Medicine as the neoadjuvant treatment in reducing the incidence of hepatocellular carcinoma in patients with hepatitis B-related cirrhosis: A systematic review and meta-analysis

Background

Traditional Chinese Medicine (TCM), has been used for hepatocellular carcinoma (HCC) at every therapeutic stage, even before tumor formation. However, the efficacy of TCM in reducing the incidence of HCC in patients with chronic hepatitis B-related cirrhosis remains unclear. This study aims to address this gap.

Methods

Publications were collected from PubMed, EMBASE, Cochrane Library, Web of Science, CNKI, Sino Med, VIP, and Wan Fang Databases. Relative risk (RR) was calculated with a 95 % confidence interval (CI). Heterogeneity was assessed. The Cochrane Collaboration's tool was used to assess the risk of bias.

Results

10 studies with 2702 patients showed that the combination therapy significantly reduced the incidence of HCC in patients with post-hepatitis B cirrhosis at 1, 3, and 5 years. However, the preventive effects of TCM were in compensated cirrhosis, but not the decompensated cirrhosis. Furthermore, TCM correlated with improved liver function and enhanced virological response.

Conclusion

Combination therapy with TCM demonstrated the certain potential in reducing the incidence of HCC in patients with hepatitis B cirrhosis. This is attrinuted to the improvement of liver function and enhancement of the viral response. However, the efficacy of TCM in the field still needs more high-quality RCTs to provide stronger evidence in the future.

Hepatitis-B virus: replication cycle, targets, and antiviral approaches

An estimated 257 million people are chronic carriers of hepatitis-B virus (HBV) infection, which resulted in around 1 million deaths, mainly due to hepatocellular carcinoma (HCC). Long-term nucleotide analog treatment of HBV infection is associated with favorable prognosis, no disease progression, and a reduction of HCC risk, but lifelong treatments are required. A better understanding of HBV replication cycle and the host immune response will likely improve the identification of new targets for drug development. Studies are ongoing to determine if it is possible to successfully combine direct-acting antivirals (DAA) with an immunomodulatory therapy to allow increased cure rates. This review will start with summarizing the HBV replication cycle, recall current treatments, and then discuss potential targets and antiviral approaches in development to optimistically reach the HBV cure.

Natural History and Hepatitis B Virus Surface Antigen (HBsAg) Spontaneous Seroclearance in Hepatitis B Virus e-Antigen (HBeAg)-Negative Patients with Inactive Chronic Infection: A Multicenter Regional Study from South Italy

Spontaneous HBsAg seroclearance has been mainly studied in populations from Asia, Australia, the Pacific Islands, and Polynesia. For the first time, we evaluated the spontaneous HBsAg seroclearance and its possible associated factors and the risk of disease progression in HBeAg-negative patients with inactive infection all coming from the same region in South Italy. In this multicenter retrospective study, 146 patients were selected after 18 months of observation and followed for a median of 82 months (IQR 60-107). For our analyses, they were divided into three groups based on their HBsAg levels: <100 IU/mL, 100-1000 IU/mL, and >1000 IU/mL. Crude and adjusted hazard ratios (HRs) for HBsAg seroclearance were determined. During the follow-up period, three patients (2.0%) showed a disease progression with an increased liver stiffness, whereas 17 (11.6%) cleared the HBsAg. Patients with HBsAg levels <100 IU/mL had the highest probability of HBsAg seroclearance compared to the other two groups (p = 0.009). In the multivariate analysis, the HBsAg level <100 IU/mL was the only parameter independently associated with HBsAg seroclearance (adjusted HR = 3.53; CI 1.29-9.69; p = 0.01). In patients with chronic HBV inactive infection, HBsAg levels <100 IU/mL predicted the highest probability of HBsAg seroclearance.

Hepatitis B infection status among South Africans attending public health facilities over a five-year period: 2015 to 2019

Hepatitis B, a potentially life-threatening viral infection of the liver, remains a global public health concern despite the availability of effective vaccines for over three decades. The aim of our study was to provide national data on active hepatitis B infections in the public health sector of South Africa. We conducted retrospective analyses on national laboratory data over the period 2015 to 2019. We identified 176,530 cases who tested positive for HBsAg (active infection) with a test positivity rate of 9.02%. Of these active infections, 11,355 (6.43%) were found to be chronically infected. We linked 24,839 (14.07%) and 2,461 (21.67%) HBeAg positive results to all active HBV infections and identified chronic infections respectively. Clearance of HBsAg was observed in 5,569 cases, inclusive of clearance in 135 chronic cases. Active HBV infections were significantly higher in men than women over the five years (p < 0.0001). Among individuals who were vaccine-eligible as infants (0 to 19 years old), we observed 4,981 active HBV infections, including 1,131 infections under five years old, majority of which (65.78%) were under one year old. In the under five-year age group, the HBsAg population positivity rate was 0.02% and test positivity rate was 4.83%. Among all women with active HBV infections (78,935), 85.17% were of reproductive age and of these, 13.73% were HBeAg positive. Without a birth dose of the HBV vaccine, lack of routine HBsAg screening at antenatal care, and HBsAg and HBeAg prevalence among women of reproductive age, it is likely that the majority of cases under five years old were vertically infected. Optimal HBV vaccine coverage, inclusive of a birth dose, is key to eliminating horizontal and vertical transmission of HBV. Early identification of HBV chronicity through real time data analysis is fundamental in reducing the risk of liver cirrhosis and hepatocellular carcinoma.

Implications of viral infections and oncogenesis in uterine cervical carcinoma etiology and pathogenesis

Background

Uterine Cervical Carcinoma (UCC) is the most prevalent gynecological malignancy globally, with a rising incidence in recent years. Accumulating evidence indicates that specific viral infections, including human papillomavirus (HPV), Epstein-Barr virus (EBV), Hepatitis B and C viruses (HBV and HCV), and human herpesvirus (HHV), may contribute to UCC development and progression. Understanding the complex interplay between viral infections and UCC risk is crucial for developing novel preventative and therapeutic interventions.

Methods

This comprehensive review investigates the association between viral infections and UCC risk by examining the roles of various viral pathogens in UCC etiology and pathogenesis, and possible molecular mechanisms. Additionally, we evaluate current diagnostic methods and potential therapeutic strategies targeting viral infections for UCC prevention or treatment.

Results

The prevention of UCC has been significantly advanced by the emergence of self-sampling for HPV testing as a crucial tool, allowing for early detection and intervention. However, an essential challenge in UCC prevention lies in understanding how HPV and other viral coinfections, including EBV, HBV, HCV, HHV, HIV, or their concurrent presence, may potentially contribute to UCC development. The molecular mechanisms implicated in the association between viral infections and cervical cancer development include: (1) interference of viral oncogenes with cellular regulatory proteins, resulting in uncontrolled cell proliferation and malignant transformation; (2) inactivation of tumor suppressor genes by viral proteins; (3) evasion of host immune responses by viruses; (4) induction of a persistent inflammatory response, contributing to a tumor-promoting microenvironment; (5) epigenetic modifications that lead to aberrant gene expression; (6) stimulation of angiogenesis by viruses; and (7) activation of telomerase by viral proteins, leading to cellular immortalization. Additionally, viral coinfections can also enhance oncogenic potential through synergistic interactions between viral oncoproteins, employ immune evasion strategies, contribute to chronic inflammation, modulate host cellular signaling pathways, and induce epigenetic alterations, ultimately leading to cervical carcinogenesis.

Conclusion

Recognizing the implications of viral oncogenes in UCC etiology and pathogenesis is vital for addressing the escalating burden of UCC. Developing innovative preventative and therapeutic interventions requires a thorough understanding of the intricate relationship between viral infections and UCC risk.

HBV genotype-dependent association of HLA variants with the serodecline of HBsAg in chronic hepatitis B patients

Seroclearance of hepatitis B surface antigen (HBsAg) is regarded as the functional cure for chronic hepatitis B (CHB). The relationship between human leukocyte antigen (HLA) variants, hepatitis B virus genotype, and longitudinal HBsAg serodecline remains to be explored. A total of 1735 HBeAg-seronegative CHB patients with genotype B or C infection of the community-based REVEAL-HBV cohort were genotyped for rs1710 (HLA-G) and rs2770 (HLA-B) using TaqMan assay. Cox proportional hazard regression and generalized linear mixed models were used to analyze the association of HLA genetic variants with the rate of HBsAg seroclearance and longitudinal HBsAg serodecline. Rs1710 G allele was differentially associated with the HBsAg seroclearance in genotype B [aRR (95% CI) = 0.74 (0.56-0.98)] and genotype C [aRR (95%CI) = 1.43 (1.08-1.88)] infection. Rs2770 G allele was associated with HBsAg seroclearance only in genotype B infection [aRR (95% CI) = 0.69 (0.52-0.91)]. The alleles associated with HBsAg seroclearance were significant predictors for the serodecline of HBsAg levels in an HBV genotype-dependent manner (genotype B infection: rs1710, P = 0.013; rs2770, P = 0.0081; genotype C infection: rs1710, P = 0.0452). Our results suggest both spontaneous HBsAg seroclearance and serodecline are modified by the interaction between HLA variants and HBV genotype.

Interferon and interferon-stimulated genes in HBV treatment

Human hepatitis B virus (HBV) is a small enveloped DNA virus with a complex life cycle. It is the causative agent of acute and chronic hepatitis. HBV can resist immune system responses and often causes persistent chronic infections. HBV is the leading cause of liver cancer and cirrhosis. Interferons (IFNs) are cytokines with antiviral, immunomodulatory, and antitumor properties. IFNs are glycoproteins with a strong antiviral activity that plays an important role in adaptive and innate immune responses. They are classified into three categories (type I, II, and III) based on the structure of their cell-surface receptors. As an effective drug for controlling chronic viral infections, Type I IFNs are approved to be clinically used for the treatment of HBV infection. The therapeutic effect of interferon will be enhanced when combined with other drugs. IFNs play a biological function by inducing the expression of hundreds of IFN-stimulated genes (ISGs) in the host cells, which are responsible for the inhibiting of HBV replication, transcription, and other important processes. Animal models of HBV, such as chimpanzees, are also important tools for studying IFN treatment and ISG regulation. In the present review, we summarized the recent progress in IFN-HBV treatment and focused on its mechanism through the interaction between HBV and ISGs.

Heterogeneity of immune control in chronic hepatitis B virus infection: Clinical implications on immunity with interferon-α treatment and retreatment

Hepatitis B virus (HBV) infection is a global public health issue. Interferon-α (IFN-α) treatment has been used to treat hepatitis B for over 20 years, but fewer than 5% of Asians receiving IFN-α treatment achieve functional cure. Thus, IFN-α retreatment has been introduced to enhance antiviral function. In recent years, immune-related studies have found that the complex interactions between immune cells and cytokines could modulate immune response networks, in-cluding both innate and adaptive immunity, triggering immune responses that control HBV replication. However, heterogeneity of the immune system to control HBV infection, particularly HBV-specific CD8⁺ T cell heterogeneity, has consequ-ential effects on T cell-based immunotherapy for treating HBV infection. Altogether, the host’s genetic variants, negative-feedback regulators and HBV components affecting the immune system's ability to control HBV. In this study, we reviewed the literature on potential immune mechanisms affecting the immune control of HBV and the clinical effects of IFN-α treatment and retreatment.

Serum HBcrAg and Hepatocellular Carcinoma in a Taiwanese Population Seronegative for HBsAg and Anti-HCV

BACKGROUND & AIMS

Hepatitis B core-related antigen (HBcrAg) is a surrogate seromarker of intrahepatic hepatitis B virus covalently closed circular DNA quantity and activity and a predictor of hepatocellular carcinoma (HCC) in chronic hepatitis B patients. We assess association between HBcrAg and HCC in individuals seronegative for hepatitis B surface antigen and anti-hepatitis C virus (NBNC) in Taiwan.

METHODS

A total of 129 newly developed HCC cases and 520 frequency-matched non-HCC controls were drawn from the REVEAL-NBNC cohort. Serum HBcrAg and other risk factors measured at recruitment were compared between cases and controls. Regression analysis was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

The proportion of baseline HBcrAg positivity (≥1000 U/mL) was significantly higher in HCC cases than in controls (12.4% vs 1.4%, P < .001). In multivariate analysis, HBcrAg positivity was associated with significantly higher risk of HCC (adjusted OR [95% CI]: 9.3 [3.3-26.4]; P < .001]. The HCC population attributable to HBcrAg positivity was 11.1% (95% CI: 9.7%-12.5%).

CONCLUSIONS

Seropositivity of HBcrAg might identify a subset of the NBNC population at higher risk of HCC in hepatitis B virus endemic areas.

Evaluating the potential cost-effectiveness of microarray patches to expand access to hepatitis B birth dose vaccination in low-and middle-income countries: A modelling study

Timely birth dose vaccination is key for achieving elimination of hepatitis B, however, programmatic requirements for delivering current vaccine presentations to births outside of health facilities inhibits coverage within many low-and middle-income countries (LMICs). Vaccine technologies in development such as microarray patches (MAPs) could assist in overcoming these barriers, but procurement could incur higher per-dose commodity costs than current ten-dose (US$0.34) and single-dose (US$0.62) vial presentations, necessitating an evaluation of the economic value proposition for MAPs. Within 80 LMICs offering universal hepatitis B birth dose vaccination, the cost-effectiveness of using MAPs to expand coverage was evaluated using a mathematical model. We considered three potential per dose MAP prices (US$1.65, US$3.30, and US$5.00), and two potential MAP use-cases: (1) MAPs are used by lay-health workers to expand birth dose coverage outside of health facility settings, and (2) MAPs are also preferred by qualified health workers, replacing a proportion of existing coverage from vaccine vials. Analysis took the health system perspective, was costed in 2020 US$, and discounted at 3% annually. Across minimal (1% additional coverage) and maximal (10% additional and 10% replacement coverage) MAP usage scenarios, between 2.5 (interquartile range [IQR]: 1.9, 3.1) and 38 (IQR: 28,44) thousand DALYs were averted over the estimated 2020 birth cohort lifetime in 80 LMICs. Efficiency of MAPs was greatest when used to provide additional coverage (scenario 1), on average saving US$88.65 ($15.44, $171.22) per DALY averted at a price of US$5.00 per MAP. Efficiency was reduced when used to replace existing coverage (scenario 2); however, at prices up to US$5.00 per MAP, we estimate this use-case could remain cost-effective in at least 73 (91%) modelled LMICs. Our findings suggest even at higher procurement costs, MAPs are likely to represent a highly cost-effective or cost-saving mechanism to expand reach of birth dose vaccination in LMICs.

HBsAg Loss as a Treatment Endpoint for Chronic HBV Infection: HBV Cure

Despite the availability of effective vaccines and antiviral therapy over the past two to three decades, chronic hepatitis B virus (HBV) infection remains a major global health threat as a leading cause of cirrhosis and liver cancer. Functional HBV cure defined as hepatitis B surface antigen (HBsAg) loss and undetectable serum HBV DNA is associated with improved clinical outcomes in patients with chronic HBV infection. However, spontaneous loss of HBsAg is rare and occurs in only 1% of all HBsAg-positive individuals annually. Furthermore, the rate of functional cure with currently available antiviral therapy is even lower, <1% patients on treatment per year. Nonetheless, HBsAg loss has become the new target or therapeutic endpoint for antiviral treatment. Recently, there has been much excitement surrounding the development of novel antiviral agents such as small interfering RNA (siRNA), core assembly modulators (CAMs), nucleic acid polymers (NAPs) among others, which may be used in combination with nucleos(t)ide analogs and possibly immunomodulatory therapies to achieve functional cure in a significant proportion of patients with chronic hepatitis B. Novel assays with improved sensitivity for detection of very low levels of HBsAg and to determine the source of HBsAg production will also be required to measure efficacy of newer antiviral treatments for HBV cure. In this narrative review, we will define HBV cure, discuss various sources of HBsAg production, evaluate rates of HBsAg loss with current and future antiviral agents, review clinical factors associated with spontaneous HBsAg loss, and explore clinical implications of functional cure.

Consolidation treatment needed for sustained HBsAg-negative response induced by interferon-alpha in HBeAg positive chronic hepatitis B patients

Hepatitis B surface antigen (HBsAg) clearance is considered as functional cure in patients with chronic hepatitis B (CHB). This study aimed to assess the durability of HBsAg clearance achieved by interferon-based therapies in patients with CHB who were originally positive for hepatitis B envelope antigen (HBeAg). In this prospective study, HBeAg-positive CHB patients with confirmed HBsAg loss under interferon-based therapies were enrolled within 12 weeks from end of treatment and followed up for 48 weeks. Virological markers, biochemical indicators, and liver imaging examinations were observed every 3–6 months. Sustained functional cure was analysed as primary outcome. Factor associated with sustained HBsAg loss or reversion was also investigated. The rate of HBsAg loss sustainability was 91.8% (212/231). Patients receiving consolidation treatment for 12–24 weeks or ≥ 24 weeks had higher rates of sustained HBsAg negativity than those receiving consolidation treatment for < 12 weeks (98.3% and 91.2% vs. 86.7%, P ​= ​0.068), and the former groups had significantly higher anti-HBs levels than the later (P ​< ​0.05). The cumulative incidence of HBsAg reversion and HBV DNA reversion was 8.2% and 3.9%, respectively. Consolidation treatment of ≥ 12 weeks [odd ratio (OR) 3.318, 95% confidence interval (CI) 1.077–10.224, P ​= ​0.037) was a predictor of sustained functional cure, and HBeAg-positivity at cessation of treatment (OR 12.271, 95% CI 1.076–139.919, P ​= ​0.043) was a predictor of HBsAg reversion. Interferon-alpha induced functional cure was durable and a consolidation treatment of ≥ 12–24 weeks was needed after HBsAg loss in HBeAg-positive CHB patients.

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It is a large prospective study of clinical cure in HBeAg-positive CHB patients.

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It showed the functional cure induced by interferon-alpha was durable.

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The extended IFN therapy is critical for HBsAg loss in HBeAg-positive CHB patients.

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Therapy of IFN consolidation ≥12–24 weeks is necessary in the clinical cure of CHB.

Viral hepatitis: Innovations and expectations

Viral hepatitis is a significant health problem worldwide, associated with morbidity and mortality. Hepatitis B, C, D, and occasionally E viruses (HBV, HCV, HDV, and HEV) can evolve in chronic infections, whereas hepatitis A virus (HAV) frequently produces acute self-limiting hepatitis. In the last years, different studies have been performed to introduce new antiviral therapies. The most important goal in the treatment of viral hepatitis is to avoid chronic liver disease and complications. This review analyzes currently available therapies, in particular for viruses associated with chronic liver disease. The focus is especially on HBV and HCV therapies, investigating new drugs already introduced in clinical practice and clinical trials. We also describe new entry inhibitors, developed for the treatment of chronic HDV and HBV and currently available treatments for HEV. The last drugs introduced have shown important efficacy in HCV, with achievable target HCV elimination by 2030. Concurrently, renewed interest in curative HBV therapies has been registered; current nucleotide/ nucleoside analogs positively impact liver-related complications, ensuring high safety and tolerability. Novel approaches to HBV cure are based on new antivirals, targeting different steps of the HBV life cycle and immune modulators. The improved knowledge of the HDV life cycle has facilitated the development of some direct-acting agents, as bulevirtide, the first drug conditionally approved in Europe for HDV associated compensated liver disease. Further studies are required to identify a new therapeutic approach in hepatitis E, especially in immunosuppressed patients.

Systematic review with meta-analysis: the impact of functional cure on clinical outcomes in patients with chronic hepatitis B

BACKGROUND

Although hepatitis B surface antigen (HBsAg) loss is considered the ideal therapeutic endpoint for the treatment of chronic hepatitis B virus (HBV) infection, its impact on clinical outcomes remains uncertain.

AIM

To assess the impact of HBsAg loss on clinical outcomes following spontaneous and treatment-related HBsAg loss.

METHODS

We searched PUBMED, Embase, the Cochrane library, and published abstracts through to May 2021 for studies that reported HBsAg loss, had >1 year of follow-up and reported at least one clinical outcome in adults with chronic HBV infection.

RESULTS

We identified 57 studies (258 744 HBsAg-positive patients, 63 270 with HBsAg loss). Based on 24 studies including 160 598 patients with and without HBsAg loss, HBsAg loss was associated with a non-significant 23% relative risk reduction of developing hepatocellular carcinoma (HCC) compared to those who remained HBsAg-positive (RR = 0.77; 95% CI: 0.38-1.57). In subgroup meta-analysis of 10 studies, treatment-related HBsAg loss was associated with a non-significant higher pooled proportion of HCC (0.94%) compared to spontaneous HBsAg loss (0.45%). HCC development after HBsAg loss was significantly higher in males, those with underlying cirrhosis, and those with a family history of HCC. HBsAg loss was associated with lower pooled proportions of incident cirrhosis, hepatic decompensation, overall and liver-related mortality compared to no HBsAg loss. Substantial heterogeneity was noted across studies for all outcomes.

CONCLUSION

HBsAg loss is associated with a reduced risk of clinical outcomes. However, several shortcomings in the published studies prevent a more definitive conclusion on the potential benefits of HBsAg loss.

Role of hepatosteatosis in HBsAg seroconversion in HBeAg-negative chronic hepatitis B patients

BACKGROUND

In chronic Hepatitis B virus (HBV) infection, certain individual and viral characteristics such as advanced age, presence of hepatic steatosis (HS), normal ALT levels, initially negative HBeAg and HBV DNA, and genotype of the virus are associated with HBsAg seroclearance and seroconversion. Herein, we report the results of our study evaluating the association between hepatosteatosis and HbsAg seroconversion.

METHODS

The clinical and biochemical data of patients with CHB and hepatosteatosis (HS) (HBsAg seroconversion, n:52, and non-HbsAg seroconversion, n:352), and the rate of development of HBsAg seroconversion were evaluated.

RESULTS

We collected data from 404 patients with HBeAg negative CBH (mean age ± SD: 36.2 ± 11 years; 223 [55.2%] men, 181 [44.8%] women). The mean age at diagnosis of disease was 36.2 ± 11 years. The mean duration of the disease was 10.6 ± 7 years. Seroconversion developed in 52 patients (12.8%) with serum HBsAg positive (mean ± SD: 12.7 ± 5.8). Elderly age and the duration of disease time were significantly associated with seroconversion (P < .001). The presence of serum HBsAg seroconversion was significantly associated with hepatosteatosis (OR: 3.06, 95% CI 1.64-5.71, P < .01). Serum HBsAg seroconversion was more frequent in patients with mild HS than patients with moderate-severe HS (P = .04). In multivariate regression analysis, the presence of HS was found to be an independent factor predicting the development of HBsAg seroconversion (OR: 2.07 95% GA:1.07-4.0 P = .03).

CONCLUSION

The presence of mild HS in HBeAg negative chronic hepatitis B patients contributes to HBsAg seroconversion. Further studies are required to better understand the relationship between steatosis and HBsAg seroconversion.

How to interpret viral markers in the management of chronic hepatitis B infection

BACKGROUND

Hepatitis B virus (HBV) infection is a global public health issue with several unsolved clinical challenges. As multiple new drugs are under development, HBV markers are gaining importance for both diagnostic and prognostic purposes.

OBJECTIVES

This review summarizes the most important data on the usefulness of HBV markers in the natural history of this infection, and in predicting clinical and treatment outcomes.

SOURCES

Selected peer-reviewed publications on HBV markers published between January 2009 and July 2021.

CONTENT

In addition to the classical markers (e.g. HBV-DNA), newer ones, such as quantitative HBsAg, HBcrAg, HBV-RNA and quantitative anti-HBc, have proven useful for predicting events within the natural history of HBV infection, the development of complications (e.g. hepatocellular carcinoma) and the response to antiviral therapy. Most data regarding the response to treatment have been related to nucleos(t)ide analogues, whereas evidence on new therapeutic agents, such as capsid assembly modulators or small interference RNAs, is promising, but still scarce.

IMPLICATIONS

Knowledge on the use of viral markers is a key factor for optimizing the clinical appraisal of HBV infection. The new markers have an enhanced ability to predict clinical outcomes. Further studies should expand the current evidence on the use of markers in relation to antiviral agents currently under evaluation. Wide availability of these markers in regions with a high incidence of HBV infection is of paramount importance.

No influence of hepatic steatosis on the 3-year outcomes of patients with quiescent chronic hepatitis B

The influence of hepatic steatosis on the natural history of chronic hepatitis B (CHB) virus is unclear. Therefore, we investigated whether concurrent steatosis in patients with CHB influences the probability of hepatitis B surface antigen (HBsAg) loss, fibrosis progression and hepatocellular carcinoma (HCC) development. This study enrolled treatment-naïve patients with virologically (HBV DNA <2,000 IU/ml) and biochemically (alanine aminotransferase level <40 IU/L) quiescent CHB who underwent transient elastography between January 2004 and December 2015 and completed 3 years of follow-up. RESULTS: The mean age of the study population (n = 720) was 52.0 years, and there were more men than women (n = 419, 58.2%). The mean HBV DNA level was 321.6 IU/ml. During the 3-year period, 74 (10.3%) patients achieved HBsAg seroclearance. Lower HBV DNA levels (hazard ratio = 0.995, p < .05) were independently associated with HBsAg seroclearance, while hepatic steatosis was not (p > .05). Fibrosis progressed in 89 (12.4%) patients. Male gender (odds ratio [OR] = 1.720) and higher body mass index (OR = 1.083) were independently associated with an increased probability of fibrosis progression (all p < .05), while higher total cholesterol levels (OR = 0.991) and higher liver stiffness values (OR = 0.862) were independently associated with a decreased probability of fibrosis progression (all p < .05). HCC developed in 46 (6.4%) patients. Male gender (OR = 3.917) and higher AST levels (OR = 1.036) were independently associated with an increased probability of HCC development (p < .05). Hepatic steatosis was not associated with the probability of HBsAg seroclearance, fibrosis progression or HCC development in patients quiescent CHB in our study. Further studies with longer follow-up periods are required to validate our findings.

Seroreversion of hepatitis B surface antigen among subjects with resolved hepatitis B virus infection: A community-based cohort study

BACKGROUND AND AIM

Hepatitis B virus (HBV) surface antigen (HBsAg) seroreversion usually occurs during immunosuppressive therapy. The risk and factors of HBsAg seroreversion from resolved HBV infection in the general population remained unclear.

METHODS

This retrospective study enrolled subjects with resolved HBV infection and who had received at least two times of screening in a longitudinal community screening program. HBsAg, hepatitis B surface antibody (anti-HBs), and hepatitis C virus antibody (anti-HCV) were tested every time in all subjects. The primary endpoint was HBsAg seroreversion.

RESULTS

Of the 7630 subjects enrolled, 5158 (67.6%) subjects had positive anti-HBs at baseline. HBsAg seroreversion occurred in 84 subjects during 42 815-person-year follow-up with an annual incidence of 0.2% and a 10-year cumulative risk of 1.9%. Anti-HBV treatment-experienced subjects had a significantly higher risk of HBsAg seroreversion than anti-HBV treatment-naive subjects (83/310 [26.8%] vs 1/7320 [0.01%], P < 0.001). Lower rates of positive anti-HBs and anti-HCV were observed in anti-HBV treatment-experienced subjects who developed HBsAg seroreversion. Both positive anti-HBs (hazard ratio/95% confidence interval: 0.56/0.348-0.903, P = 0.017) and positive anti-HCV (hazard ratio/95% confidence interval: 0.08/0.030-0.234, P < 0.001) were independent factors of HBsAg seroreversion in anti-HBV treatment-experienced subjects. Less than 5% of the HBsAg seroreverters had clinical hepatitis flare at HBsAg seroreversion. The HBsAg titer was low, and only transient reappeared in most of the HBsAg seroreverters.

CONCLUSIONS

Subjects with resolved HBV infection were at a minimal risk of HBsAg seroreversion, unless with prior anti-HBV treatment experience. Fortunately, even with a reappearance of HBsAg, it was transient and clinically non-relevant.

Guidelines for Prevention and Treatment of Chronic Hepatitis B

To achieve the goal of the World Health Organization to eliminate viral hepatitis as a major public health threat by 2030, the Chinese Society of Infectious Diseases and the Chinese Society of Hepatology convened an expert panel in 2019 to update the guidelines for the prevention and treatment of chronic hepatitis B (CHB). The current guidelines cover recent advances in basic, clinical, and preventive studies of CHB infection and consider the actual situation in China. These guidelines are intended to provide support for the prevention, diagnosis, and treatment of CHB.

Nanomedicine as a promising strategy for the theranostics of infectious diseases

Infectious diseases caused by bacteria, viruses, and fungi and their global spread pose a great threat to human health. The 2019 World Health Organization report predicted that infection-related mortality will be similar to cancer mortality by 2050. Particularly, the global cumulative numbers of the recent outbreak of coronavirus disease (COVID-19) have reached 110.7 million cases and over 2.4 million deaths as of February 23, 2021. Moreover, the crisis of these infectious diseases exposes the many problems of traditional diagnosis, treatment, and prevention, such as time-consuming and unselective detection methods, the emergence of drug-resistant bacteria, serious side effects, and poor drug delivery. There is an urgent need for rapid and sensitive diagnosis as well as high efficacy and low toxicity treatments. The emergence of nanomedicine has provided a promising strategy to greatly enhance detection methods and drug treatment efficacy. Owing to their unique optical, magnetic, and electrical properties, nanoparticles (NPs) have great potential for the fast and selective detection of bacteria, viruses, and fungi. NPs exhibit remarkable antibacterial activity by releasing reactive oxygen species and metal ions, exerting photothermal effects, and causing destruction of the cell membrane. Nano-based delivery systems can further improve drug permeability, reduce the side effects of drugs, and prolong systemic circulation time and drug half-life. Moreover, effective drugs against COVID-19 are still lacking. Recently, nanomedicine has shown great potential to accelerate the development of safe and novel anti-COVID-19 drugs. This article reviews the fundamental mechanisms and the latest developments in the treatment and diagnosis of bacteria, viruses, and fungi and discusses the challenges and perspectives in the application of nanomedicine.

Detection of the serological markers hepatitis B virus surface antigen (HBsAg) and hepatitis B core IgM antibody (anti-HBcIgM) in the diagnosis of acute hepatitis B virus infection after recent exposure

The serological diagnosis of acute hepatitis B virus (HBV) infection after recent exposure has been established by the hepatitis B virus surface antigen (HBsAg) and anti-hepatitis B core IgM antibody (anti-HBcIgM) detection in serum, sometimes accompanied by the detection of hepatitis B "e" antigen (HBeAg). Despite this characteristic serological profile, misdiagnosis can occur in cases of unexpected or atypical behavior of the serological markers in the bloodstream, or if the true meaning of its expression is not properly investigated, or even if there is a possibility of interference from factors not necessarily linked to the infectious process, in the detection of these markers. This review discusses the influence of these variables on laboratory results for these two serological markers and, therefore, the potential risk of these variables compromising the correct diagnosis of acute infection after recent HBV exposure.

B Cell-mediated Humoral Immunity in Chronic Hepatitis B Infection

B cell-mediated humoral immunity plays a vital role in viral infections, including chronic hepatitis B virus (HBV) infection, which remains a critical global public health issue. Despite hepatitis B surface antigen-specific antibodies are essential to eliminate viral infections, the reduced immune functional capacity of B cells was identified, which was also correlated with chronic hepatitis B (CHB) progression. In addition to B cells, T follicular helper (Tfh) cells, which assist B cells to produce antibodies, might also be involved in the process of anti-HBV-specific antibody production. Here, we provide a comprehensive review of the role of various subsets of B cells and Tfh cells during CHB progression and discuss current novel treatment strategies aimed at restoring humoral immunity. Understanding the mechanism of dysregulated B cells and Tfh cells will facilitate the ultimate functional cure of CHB patients.

Challenges and opportunities for hepatitis B cure in the setting of HIV--hepatitis B virus co-infection

PURPOSE OF REVIEW

To examine issues specific to HIV--HBV co-infection that are relevant to the search for and achieving hepatitis B cure in this the setting RECENT FINDINGS: In HIV--HBV co-infection, high rates of hepatitis B surface antigen (HBsAg) loss early after initiation of HBV-active antiretroviral therapy (ART) have previously been reported. Between 2012 and 2016, HBsAg loss from 2.8 to 23% was reported in numerous studies, including those already on suppressive HBV-active ART. Data published in 2018-2019 show that these rates have remained fairly stable (3.0-13.9%). However, it appears that higher HBsAg loss on starting HBV-active ART in co-infection falls within a few years to levels similar to that observed in long-term treated HBV mono-infection. Immune reconstitution and CD4+ T-cell recovery are likely to play a role in high HBsAg loss rates seen in early treated co-infection, although the mechanisms driving this are yet to be fully elucidated.

SUMMARY

High rates of HBsAg loss early after HBV-active ART initiation is unique to HIV--HBV co-infection, making it the ideal setting to investigate underlying mechanisms of HBV loss and develop new HBV cure strategies. This phenomenon could be used to enhance HBsAg loss with new therapeutic approaches currently being investigated; however, this is obstructed by excluding co-infection from such studies.

Usefulness of a Hepatitis B Surface Antigen-Based Model for the Prediction of Functional Cure in Patients with Chronic Hepatitis B Virus Infection Treated with Nucleos(t)ide Analogues: A Real-World Study

In patients with chronic hepatitis B (CHB) under long-term treatment with nucleso(t)ide analogues (NAs), the loss of hepatitis B surface antigen (HBsAg) is a rare event. A growing body of evidence supports the use of quantitative HBsAg for the prediction of functional cure, although these results are mainly derived from studies performed on Asian patients with hepatitis B e antigen (HBeAg)-positive CHB. Here, we investigated the clinical role of quantitative HBsAg in a real-life cohort of CHB patients under treatment with NAs in a tertiary care center from North-West Italy. A total of 101 CHB patients (HBeAg-negative, n = 86) undergoing NAs treatment were retrospectively enrolled. HBsAg was measured at baseline (T0), 6 months (T1), 12 months (T2) and at the last follow-up (FU). Median FU was 5.5 (3.2–8.3) years; at the end of FU, 11 patients lost the HBsAg (annual incidence rate = 1.8%). Baseline HBsAg levels were significantly different between patients with no HBsAg loss and those achieving a functional cure (3.46, 2.91–3.97 vs. 1.11, 0.45–1.98 Log IU/mL, p < 0.001). Similarly, the HBsAg decline (Δ) from T0 to T2 was significantly different between the two groups of patients (0.05, −0.04–0.13, vs. 0.38, 0.11–0.80 Log IU/mL, p = 0.002). By stratified cross-validation analysis, the combination of baseline HBsAg and ΔHBsAg T0–T2 showed an excellent accuracy for the prediction of HBsAg loss (C statistic = 0.966). These results corroborate the usefulness of quantitative HBsAg in Caucasian CHB patients treated with antivirals for the prediction of HBsAg seroclearance.

Cost-effectiveness analysis of first-line treatment for chronic hepatitis B in China

OBJECTIVES

Hepatitis B virus infection is an important public health problem. We analysed the cost-effectiveness of the first-line therapies, including nucleotide analogues (namely tenofovir alafenamide fumarate (TAF), tenofovir disoproxil fumarate (TDF) and entecavir) and pegylated interferon (Peg-IFN) for patients with chronic hepatitis B (CHB) in China.

METHODS

A Markov model describing CHB disease progression was constructed to compare the cost-effectiveness of the first-line therapies, considering both satisfactory (HBeAg seroconversion) and optimal (HBsAg seroclearance) treatment goals. We examined the main outcomes, including cumulative lifetime cost per patient, incremental quality-adjusted life years (QALYs), incremental cost-effectiveness ratio and net monetary benefit. Uncertainty analysis was conducted to identify key influential parameters.

RESULTS

Compared with the baseline strategy, Peg-IFN had the highest QALY gain for HBeAg-positive (HBeAg+) CHB patients achieving a satisfactory goal and an optimal goal (3.19 and 6.32 respectively), and TDF was the most cost-effective therapy for HBeAg-negative CHB patients ($1418/QALY) achieving a satisfactory goal. Among nucleotide analogues, TAF was the most-effective strategy and had higher acceptability to achieve an optimal goal in the Eastern region of China (under 1 x GDP per capita threshold).

CONCLUSIONS

Among nucleotide analogues, TDF was the most cost-effective treatment in China for CHB patients to achieve satisfactory and optimal treatment goals, whereas TAF was cost-effective and more effective in the wealthier region. Peg-IFN was most cost-effective among HBeAg+ CHB patients to achieve both goals, with better clinical outcomes. Our findings also indicate the importance of regular monitoring during and after CHB treatment, and could inform treatment strategies in China and other countries.

Changes in the Hepatitis B Surface Antigen Level According to the HBeAg Status and Drug Used in Long-term Nucleos(t)ide Analog-treated Chronic Hepatitis B Patients

Backgrounds/Aims

The HBsAg levels have been used to monitor the chronic hepatitis B (CHB) treatment response to antiviral therapy. On the other hand, it is unclear if the HBsAg quantification levels at each treatment point differ according to the HBeAg status and drug in CHB patients. This study compared the changes in HBsAg in CHB patients according to the HBeAg status and treatment drugs.

Methods

CHB patients with at least 1 year of follow-up treatment with one drug, either entecavir (ETV) or tenofovir (TDF), were enrolled in this study. The mean HBsAg levels were measured annually for up to 6 years. A linear mixed model was used to compare the HBsAg quantification levels during the follow-up period. An independent samples t-test was used to analyze the differences in the HBsAg quantification levels at each treatment time point.

Results

Ninety-seven patients were enrolled in this study; 59 among them were HBeAg-positive. Two patients in the TDF group achieved HBsAg seroconversion. The HBsAg level decreased during the follow-up in the ETV and TDF groups. The HBsAg level was lower in the TDF group than the ETV group during the follow-up. On the other hand, subgroup analysis showed that this trend was the same only in the HBeAg-negative patients, not in the HBeAg-positive patients. In the HBeAg-negative patients, HBsAg level in the TDF group was significantly lower than that in the ETV group at 36, 48, and 72 months. The change in HBsAg level from the baseline increased at a decreasing rate during the follow-up in both groups. Furthermore, the change in the HBsAg level in the TDF group was significantly larger than that of the ETV group at 36 months in the HBeAg-negative patients.

Conclusions

Although TDF might be more efficient than ETV in reducing the HBsAg level in HBeAg-negative patients in a few years, HBsAg seroconversion occurred very rarely. A further large-scale, long-term study will be needed to confirm the antiviral effects on the HBsAg level.

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

BACKGROUND AND AIMS

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

APPROACH AND RESULTS

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

CONCLUSIONS

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

Understanding the antiviral effects of RNAi-based therapy in HBeAg-positive chronic hepatitis B infection

The RNA interference (RNAi) drug ARC-520 was shown to be effective in reducing serum hepatitis B virus (HBV) DNA, hepatitis B e antigen (HBeAg) and hepatitis B surface antigen (HBsAg) in HBeAg-positive patients treated with a single dose of ARC-520 and daily nucleosidic analogue (entecavir). To provide insights into HBV dynamics under ARC-520 treatment and its efficacy in blocking HBV DNA, HBsAg, and HBeAg production we developed a multi-compartmental pharmacokinetic-pharamacodynamic model and calibrated it with frequent measured HBV kinetic data. We showed that the time-dependent single dose ARC-520 efficacies in blocking HBsAg and HBeAg are more than 96% effective around day 1, and slowly wane to 50% in 1-4 months. The combined single dose ARC-520 and entecavir effect on HBV DNA was constant over time, with efficacy of more than 99.8%. The observed continuous HBV DNA decline is entecavir mediated, the strong but transient HBsAg and HBeAg decays are ARC-520 mediated. The modeling framework may help assess ongoing RNAi drug development for hepatitis B virus infection.

Spontaneous Flares of Chronic Hepatitis B Virus in Hepatitis Be Antigen Negative Carriers Who Subsequently Clear Hepatitis B Surface Antigen

BACKGROUND

Acute exacerbations of chronic hepatitis B virus (HBV) infections can occur in HBV-infected, hepatitis e antigen (HBeAg)-negative patients in the absence of recent withdrawal of antiviral or immunosuppressive therapies. Whether these spontaneous "flares" predict subsequent loss of hepatitis B surface antigen (HBsAg) has yet to be determined.

OBJECTIVES

To document the percent of patients who experience spontaneous HBV flares and severity of the flares in chronic HBeAg-negative carriers.

METHODS

A retrospective review of an HBV database identified and followed HBeAg-negative patients for biochemical evidence of flares (ALT > 5× normal) and subsequent HBsAg status. Patients that subsequently cleared HBsAg were matched 1:1 with those who remained HBsAg positive.

RESULTS

Of 1299 HBeAg-negative patients followed for 10.2 ± 6.1 years, 88 (6.8%) developed spontaneous HBV flares. Flares occurred in 14/115 (12.2%) patients who subsequently cleared HBsAg and 4/111 (3.6%) matched patients who remained HBsAg positive (p = 0.025). The severity of flares was similar in the two study cohorts. Following multivariate analyses, only low HBV-DNA levels at baseline identified patients likely to subsequently clear HBsAg.

CONCLUSIONS

Although more common in patients who subsequently clear HBsAg, spontaneous HBV flares do not predict subsequent HBsAg clearance.

Prediction Model of HBsAg Seroclearance in Patients with Chronic HBV Infection

Background

Prediction of HBsAg seroclearance, defined as the loss of circulating HBsAg with or without development of antibodies for HBsAg in patients with chronic hepatitis B (CHB), is highly difficult and challenging due to its low incidence. This study is aimed at developing and validating a nomogram for prediction of HBsAg loss in CHB patients.

Methods

We analyzed a total of 1398 patients with CHB. Two-thirds of the patients were randomly assigned to the training set (n = 918), and one-third were assigned to the validation set (n = 480). Univariate and multivariate analysis by Cox regression analysis was performed using the training set, and the nomogram was constructed. Discrimination and calibration were performed using the training set and validation set.

Results

On multivariate analysis of the training set, independent factors for HBsAg loss including BMI, HBeAg status, HBsAg titer (quantitative HBsAg), and baseline hepatitis B virus (HBV) DNA level were incorporated into the nomogram. The HBsAg seroclearance calibration curve showed an optimal agreement between predictions by the nomogram and actual observation. The concordance index (C-index) of nomogram was 0.913, with confirmation in the validation set where the C-index was 0.886.

Conclusions

We established and validated a novel nomogram that can individually predict HBsAg seroclearance and non-seroclearance for CHB patients, which is clinically unprecedented. This practical prognostic model may help clinicians in decision-making and design of clinical studies.

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

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

Hepatitis B Surface Antigen Levels Are Related to Spontaneous Hepatitis B Surface Antigen Seroconversion in Inactive Hepatitis B Carriers

BACKGROUND

The cure for hepatitis B is defined as the hepatitis B surface antigen (HBsAg) seroclearance and/or seroconversion. Predictors of spontaneous seroconversion are not well described. The objective of this study is to identify predictors of spontaneous HBsAg seroconversion from community practice.

METHODS

We performed a matched analysis of patients who HBsAg seroconverted (cases) and patients who did not HBsAg seroconvert (control) in a 1:5 ratio according to date of clinic visit between 2014 and 2019 in a large community practice situated in Los Angeles area. Baseline laboratory and clinical data were collected. Univariate analysis and 2-sided t tests were performed, χ test for proportions, and logistic regression.

RESULTS

We identified 14 cases and 70 controls. The mean (±SD) ages of the cases and controls were 53.6 (±12.2) and 49.5 (±13.1), respectively (P=0.45). Most patients were women, and all patients were of Asian descent. There were statistically significant mean (±SD) baseline differences between cases and controls in HBsAg titers (459.8±311.0 and 782.0±393.3 IU/mL, P=0.01) and alanine aminotransferase (ALT) values (17.6±4.4 and 25.1±16.7 IU/mL, P<0.01), respectively. Baseline hepatitis B virus DNA and other pertinent laboratory values did not differ between cases and controls. Eleven of 14 cases (79%) and 11 of 70 controls (16%) baseline HBsAg titers were <1000 IU/mL (P<0.01). The results of a logistic regression demonstrated that HBsAg titers and ALT values were predictor variables for HBsAg seroconversion (P=0.01 and <0.01, respectively).

CONCLUSIONS

Spontaneous HBsAg seroclearance and seroconversion is an uncommon event in patients with chronic hepatitis B. The most important predictors of seroconversion are HBsAg titers<1000 IU/mL and low baseline ALT values.

Targeting Host Innate and Adaptive Immunity to Achieve the Functional Cure of Chronic Hepatitis B

Despite the availability of an effective preventive vaccine for hepatitis B virus (HBV) for over 38 years, chronic HBV (CHB) infection remains a global health burden with around 257 million patients. The ideal treatment goal for CHB infection would be to achieve complete cure; however, current therapies such as peg-interferon and nucleos(t)ide analogs are unable to achieve the functional cure, the newly set target for HBV chronic infection. Considering the fact functional cure has been accepted as an endpoint in the treatment of chronic hepatitis B by scientific committee, the development of alternative therapeutic strategies is urgently needed to functionally cure CHB infection. A promising target for future therapeutic strategies is immune modulation to restore dysfunctional HBV-specific immunity. In this review, we provide an overview of the progress in alternative therapeutic strategies, including immune-based therapeutic approaches that enhance host innate and adaptive immunity to achieve and increase the functional cure from CHB infection.

Enhancing the hepatitis B care cascade in Australia: A cost-effectiveness model

If Australia is to successfully eliminate hepatitis B as a public health threat, it will need to enhance the chronic hepatitis B (CHB) care cascade. This study used a Markov model to assess the impact, cost and cost-effectiveness of scaling up CHB diagnosis, linkage to care and treatment to reach national and international elimination targets for hepatitis B in Australia. Compared to continued current trends, the model calculated the difference in care cascade projection, disability-adjusted life years (DALYs), costs and the incremental cost-effectiveness ratio (ICER), of scaling up CHB diagnosis, linkage to care and treatment to reach: (a) Australia's 2022 national targets and (b) the WHO's 2030 global targets. Achieving the national and WHO targets had ICERs of A$13 435 (A$10 236-A$21 165) and A$14 482 (A$13 031-A$25 641) per DALY averted between 2016 and 2030 in Australia, respectively. However, this excluded implementation and demand generation costs. The ICER for the National Strategy and WHO Strategy remained under A$50 000 per DALY averted if Australia spent up to A$328 or A$538 million, respectively, per annum (for 2016-2030) on implementation and demand generation activities. Sensitivity analysis showed that cost-effectiveness was predominately driven by the cost of CHB treatment and influenced by disease progression rates. Hence for Australia to reach the National Hepatitis B Strategy 2022 targets and WHO Strategy 2030 targets, it requires an improvement in the CHB care cascade. We estimated it is cost-effective to spend up to A$328 million or A$538 million per year to reach the National and WHO Strategy targets, respectively.

Clinical features of chronic hepatitis B patients with low hepatitis B surface antigen levels and determinants of hepatitis B surface antigen seroclearance

Background and Aim

A low hepatitis B surface antigen (HBsAg) level is reported to be predictive of future HBsAg seroclearance. A hospital-based cohort study was conducted to clarify the clinical features of patients with low HBsAg levels and to demonstrate the usefulness of low HBsAg levels for predicting HBsAg seroclearance.

Methods

A total of 1459 patients with chronic hepatitis B were included in the study. Of these, 587 had repeated measurements for HBsAg levels and two or more records of HBsAg-positive results. HBsAg levels were measured with a commercially available HBsAg assay. Based on a cut-off index (COI) of 2000, a high HBsAg level was defined as HBsAg ≥2000 COI, and a low HBsAg level was defined as HBsAg <2000 COI.

Results

The proportion of patients with low HBsAg levels at baseline tended to increase with age. Patients with low HBsAg levels at baseline had significantly older age, lower transaminase levels, and lower hepatitis B virus (HBV) DNA levels than those with high HBsAg levels. The annual HBsAg seroclearance rate was 1.30%/year. The cumulative incidences of HBsAg seroclearance differed significantly by HBsAg level at baseline (<2000 vs ≥2000 COI), age (≥50 vs <50 years), and HBV DNA level (<4.0 vs ≥4.0 log copies/mL). Cox proportional hazards regression analyses showed that low HBsAg level (<2000 COI) and low HBV DNA level (<4.0 log copies/mL) were significantly associated with HBsAg seroclearance.

Conclusion

Aging was one of the factors affecting HBsAg level. HBsAg seroclearance was significantly associated with low HBsAg level and low HBV DNA level at baseline.

The safety of stopping nucleos(t)ide analogue treatment in patients with HBeAg-negative chronic hepatitis B

BACKGROUND

The rates of hepatitis B surface antigen (HBsAg) seroclearance after stopping nucleos(t)ide analogues (NA) in European (19% in 2 years) and Asian (13% in 6 years) patients with chronic hepatitis B (CHB) vary dramatically. We evaluated the incidence of hepatitis flare and HBsAg seroclearance in hepatitis B e antigen (HBeAg)-negative Chinese CHB patients who had stopped NA.

METHODS

This was a territory-wide retrospective study in Hong Kong. We identified HBeAg-negative CHB patients from January 2000 to December 2017 who had stopped NA treatment for more than 3 months. Hepatitis flare was defined as ALT >2×ULN.

RESULTS

The 1076 patients were predominantly middle-aged men (mean age 52 years, male 74.8%) when starting NA; they stopped NA after 82 ± 35 months of treatment. At 44.3 ± 24.6 months after stopping NA, 147 (13.6%) patients had hepatitis flare, which led to resumption of NA; whereas 77 (7.2%) patients had flare but did not resume NA. Decompensation occurred in 7/914 (0.8%) patients. A total of 695 (64.6%) patients remained on NA treatment at the last visit. Eleven patients had achieved HBsAg seroclearance (6 of them had hepatitis flare and 1 of these 6 patients achieved HBsAg seroclearance after NA was restarted). Hepatic events developed in 75/695 (10.8%) patients who had NA resumed vs 43/381 (11.3%) patients who did not resume NA (P = .677).

CONCLUSIONS

Hepatitis flare and retreatment were common in HBeAg-negative CHB patients who stopped NA treatment; whereas HBsAg seroclearance rarely occurred. Stopping NA to achieve functional cure should not be recommended at this moment.

Will we need novel combinations to cure HBV infection?

Chronic hepatitis B is a numerically important cause of cirrhosis and hepatocellular carcinoma. Nucleoside analogue therapy may modify the risk. However, maintenance suppressive therapy is required, as a functional cure (generally defined as loss of HBsAg off treatment) is an uncommon outcome of antiviral treatment. Chronic hepatitis B is a numerically important cause of cirrhosis and hepatocellular carcinoma. Nucleoside analogue therapy may modify the risk. However, maintenance suppressive therapy is required, as a functional cure (generally defined as loss of HBsAg off treatment) is an uncommon outcome of antiviral treatment. Currently numerous investigational agents being developed to either interfere with specific steps in HBV replication or as host cellular targeting agents, that inhibit viral replication, and deplete or inactivate cccDNA, or as immune modulators. Synergistic mechanisms will be needed to incorporate a decrease in HBV transcription, impairment of transcription from HBV genomes, loss of cccDNA or altered epigenetic regulation of cccDNA transcription, and immune modulation or immunologically stimulated hepatocyte cell turnover. Nucleoside analogue suppressed patients are being included in many current trials. Trials are progressing to combination therapy as additive or synergistic effects are sought. These trials will provide important insights into the biology of HBV and perturbations of the immune response, required to effect HBsAg loss at different stages of the disease. The prospect of cures of hepatitis B would ensure that a wide range of patients could be deemed candidates for treatment with new compounds if these were highly effective, finite and safe. Withdrawal of therapy in short-term trials is challenging because short-term therapies may risk severe hepatitis flares, and hepatic decompensation. The limited clinical trial data to date suggest that combination therapy is inevitable.

Single-nucleotide polymorphism of rs7944135 (macrophage-expressed gene 1) is associated with hepatitis B surface antigen seroclearance in chronic hepatitis B infection: A cohort study

Clearance of the hepatitis B surface antigen (HBsAg) is the ultimate aim of treatment for patients with chronic hepatitis B (CHB) infection. Genetic, factor age, and gender were reported to be involved in the clearance of HBsAg. However, the rate of HBsAg seroclearance in CHB patients is still low globally and few of the single-nucleotide polymorphism (SNP) had been identified to associated with HBsAg seroclearance in CHB patients.Recently, 3 associated SNPs (rs7944135, rs171941, and rs6462008) were reported in the clearance of HBsAg in the Korean population. However, these SNPs have not been investigated in the CHB Taiwanese population. In present study, these 3 SNPs were genotyped in 2565 Taiwanese CHB patients including 493 CHB patients with HBsAg seroclearance and 2072 without HBsAg seroclearance.We observed that SNP rs7944135 was solely associated with HBsAg seroclearance. Subjects with the AA genotype at rs7944135 of macrophage-expressed gene 1 had a higher susceptibility to HBsAg clearance, compared to those with the AG or GG genotype under the genotypic model (odds ratio [OR] = 1.76. 95% confidence interval [CI] = 1.14-2.72, P = .045). Furthermore, we found a 1.74-fold increased risk of acquiring HBsAg seroclearance associated with the AA genotype compared to AG + GG of rs7944135 under the recessive model (OR = 1.74. 95% CI = 1.13-2.66, P = .014). According to the cumulative fraction curve with the log-rank test revealed that patients with the AA genotype of rs7944135 showed higher susceptibility to occur HBsAg seroclearance (P = .039) and HBV DNA undetectable (P = .0074) compared to those with the AG or GG genotype.This study examined the associations of 3 SNPs (rs7944135, rs171941, and rs6462008) with HBsAg seroclearance, and we identified that rs7944135 is solely associated with HBsAg seroclearance in Taiwanese CHB patients.

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

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

Predictors of sustained functional cure in hepatitis B envelope antigen-negative patients achieving hepatitis B surface antigen seroclearance with interferon-alpha-based therapy

Hepatitis B surface antigen (HBsAg) loss is considered a functional cure in chronic hepatitis B (CHB). However, the durability of HBsAg loss after stopping treatment remains unknown. This study aimed to assess the sustained functional cure achieved by interferon therapy in hepatitis B envelope antigen (HBeAg)-negative CHB patients. In this prospective study, 176 HBeAg-negative CHB patients with functional cure were enrolled for 12 weeks of cessation treatment, and treatment information and baseline data were collected. Hepatitis B virus (HBV) biomarkers and clinical biochemical indicators were evaluated every 3 months; liver imaging examinations were performed every 3-6 months during the 48-week follow-up. The sustained functional cure was evaluated. After the 48-week follow-up, the sustained functional cure rate was 86.63%. The cumulative rates of HBsAg reversion and HBV DNA reversion were 12.79% and 2.33%, respectively. Consolidation treatment ≥ 12 weeks after HBsAg loss achieved a significantly higher rate of sustained functional cure and significantly lower rate of HBsAg reversion than consolidation treatment < 12 weeks (76.19% vs 90.00%, P = 0.022 and 23.81% vs 9.23%, P = 0.014, respectively). Patients with hepatitis B surface antibody (HBsAb) had higher rate of sustained functional cure than patients achieving HBsAg loss but without HBsAb (89.86% vs 73.53%, P = 0.012). Consolidation treatment ≥ 12 weeks (odds ratio [OR] 16.478; 95% confidence interval [CI], 2.135-127.151; P = 0.007) and high HBsAb levels (OR 8.312; 95% CI, 1.824-37.881; P = 0.006) were independent predictors of sustained functional cure. Results suggested that 12 weeks of consolidation therapy after HBsAg clearance and elevated HBsAb levels help to improve functional cure.

Using Machine Learning Algorithms to Predict Hepatitis B Surface Antigen Seroclearance

Hepatitis B surface antigen (HBsAg) seroclearance during treatment is associated with a better prognosis among patients with chronic hepatitis B (CHB). Significant gaps remain in our understanding on how to predict HBsAg seroclearance accurately and efficiently based on obtainable clinical information. This study aimed to identify the optimal model to predict HBsAg seroclearance. We obtained the laboratory and demographic information for 2,235 patients with CHB from the South China Hepatitis Monitoring and Administration (SCHEMA) cohort. HBsAg seroclearance occurred in 106 patients in total. We developed models based on four algorithms, including the extreme gradient boosting (XGBoost), random forest (RF), decision tree (DCT), and logistic regression (LR). The optimal model was identified by the area under the receiver operating characteristic curve (AUC). The AUCs for XGBoost, RF, DCT, and LR models were 0.891, 0.829, 0.619, and 0.680, respectively, with XGBoost showing the best predictive performance. The variable importance plot of the XGBoost model indicated that the level of HBsAg was of high importance followed by age and the level of hepatitis B virus (HBV) DNA. Machine learning algorithms, especially XGBoost, have appropriate performance in predicting HBsAg seroclearance. The results showed the potential of machine learning algorithms for predicting HBsAg seroclearance utilizing obtainable clinical data.

A retrospective serological survey of hepatitis B virus infection in Northeast China

BACKGROUND

Hepatitis B virus (HBV) infection is a major public health burden in China although it has steadily declined over the last two decades. A valid updated prevalence of HBV infection in China relies on a large sample size. Hence this study aimed to estimate HBV seroprevalence using a large inpatient population in Northeast China.

METHODS

We consecutively enrolled 218,627 inpatients aged 1-70 years admitted to the First Hospital of Jilin University from January 2010 through December 2014. HBV serological markers were detected by chemiluminescence immunoassay (CLIA).

RESULTS

Among the 218,627 collected samples, 16,254 (7.43%) were positive for HBsAg and 41.64% of patients were negative for all the HBV markers. The highest HBsAg prevalence was 10.05% in the 41-50 year age group and the lowest were 0.47% in the 1-10 and 2.35% in the 11-20 year age groups, respectively. HBsAg positivity was higher in males compared to females (8.94% vs. 5.80%). An HBsAg positivity of nearly 14% was found in middle-aged males, and positivity was 6.2% in females of childbearing age. One-third of this population only had a single HBsAb marker, which was also detected in 60% of patients aged under 20 years.

CONCLUSION

Though universal hepatitis B vaccination of infants has significantly reduced HBsAg prevalence in children, the number of most adults who have been infected with HBV remains steady. Extra care and resources should be provided to HBV-infected middle-aged males to stop the progression of chronic hepatitis B, and HBsAg positive females of childbearing age to block vertical HBV transmission.

REP 2139: Antiviral Mechanisms and Applications in Achieving Functional Control of HBV and HDV Infection

Nucleic acid polymers (NAPs) are broad spectrum antiviral agents whose antiviral activity in hepatitis B virus (HBV) infection is derived from their ability to block the release of the hepatitis B virus surface antigen (HBsAg). This pharmacological activity blocks replenishment of HBsAg in the circulation, allowing host mediated clearance. This effect has important clinical significance as the clearance of circulating HBsAg dramatically potentiates the ability of immunotherapies to restore functional control of HBV infection which persists after antiviral therapy is removed. These effects are reproducible in preclinical evaluations and in several clinical trials that have evaluated the activity of the lead NAP, REP 2139, in monotherapy and in combination with immunotherapy in hepatitis B e antigen (HBeAg) negative and HBeAg positive HBV infection and also in HBeAg negative HBV/hepatitis D virus (HDV) coinfection. These antiviral effects of REP 2139 are achieved in the absence of any direct immunostimulatory effect in the liver and also without any discernible direct interaction with viral components. The search for the host protein interaction with NAPs that drives their antiviral effects is ongoing, and the interaction targeted by REP 2139 within infected cells has not yet been elucidated. This article provides an updated review of available data on the effects of REP 2139 in HBV and HDV infection and the ability of REP 2139-based combination therapy to achieve functional control of HBV and HDV infection in patients.