Linearized hepatitis B surface antigen and hepatitis B core-related antigen in the natural history of chronic hepatitis B

Association of Hepatitis B Surface Antigen Levels With Long-Term Complications in Chronic Hepatitis B Virus Infection: A Systematic Literature Review

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

Circulating HBV RNA and Hepatitis B Core-Related Antigen Trajectories in Persons With HIV/HBV Coinfection and Hepatitis B Surface Antigen Loss During Tenofovir Therapy

BACKGROUND

We evaluated long-term trajectories of circulating hepatitis B virus (HBV) RNA and hepatitis B core-related antigen (HBcrAg) in persons with and without hepatitis B surface antigen (HBsAg) loss during tenofovir therapy in the Swiss HIV Cohort Study.

METHODS

We included 29 persons with HIV with HBsAg loss and 29 matched persons with HIV without HBsAg loss. We compared HBV RNA and HBcrAg decline and assessed the cumulative proportions with undetectable HBV RNA and HBcrAg levels during tenofovir therapy using Kaplan-Meier estimates.

RESULTS

HBsAg loss occurred after a median of 4 years (IQR, 1-8). All participants with HBsAg loss achieved suppressed HBV DNA and undetectable HBV RNA preceding undetectable quantitative HBsAg levels, whereas 79% achieved negative HBcrAg. In comparison, 79% of participants without HBsAg loss achieved undetectable HBV-RNA and 48% negative HBcrAg. After 2 years of tenofovir therapy, an HBV RNA decline ≥1 log10 copies/mL had 100% sensitivity and 36.4% specificity for HBsAg loss, whereas an HBcrAg decline ≥1 log10 U/mL had 91.0% sensitivity and 64.5% specificity.

CONCLUSIONS

HBV RNA suppression preceded undetectable quantitative HBsAg levels and had high sensitivity but low specificity for HBsAg loss during tenofovir therapy in persons with HIV. HBcrAg remained detectable in approximately 20% of persons with HBsAg loss and 50% of persons without HBsAg loss.

Characteristics analysis of hepatitis B core-related antigen in children with hepatitis B e antigen-positive chronic viral hepatitis B infection

BACKGROUND

The objective of antiviral therapy for chronic viral hepatitis B infection (CHB) is to achieve a functional cure. An important viral marker in the serum of patients with CHB is the serum hepatitis B core-related antigen (HBcrAg). However, there is limited research on HBcrAg in juvenile patients with CHB. In this study, we aimed to investigate the correlation between serum HBcrAg and other hepatitis B virus (HBV) markers in children with CHB and its predictive significance for prognosis during antiviral therapy.

METHODS

A single-center retrospective study was conducted involving 79 children with CHB, aged between 0 and 16 years. All the children were treated with interferon [or combined nucleos(t)ide analogs] for 48 weeks. HBcrAg, hepatitis B surface antigen (HBsAg), and HBV DNA were measured before treatment, and at 12 and 48 weeks after treatment. The enrolled children were classified into the seroclearance group and the nonseroclearance group based on the therapeutic outcome.

RESULTS

HBsAg seroclearance was observed in 28 out of 79 patients and hepatitis B e antigen seroconversion without HBsAg seroclearance was observed in 14 out of 79 patients following the conclusion of the treatment, with baseline HBcrAg titer levels showing no statistical significance in both the seroclearance and nonseroclearance groups ( P  = 0.277). HBsAg and HBV DNA were positively correlated with HBcrAg in children with CHB ( R2  = 0.3289, 0.4388). The area under the receiver operating characteristic curve of the decrease in HBcrAg at 12 weeks of treatment as a predictor of seroclearance at 48 weeks of treatment, exhibited a value of 0.77.

CONCLUSION

A decrease in serum HBcrAg levels in children with hepatitis B serves as a prognostic indicator.

Profiles of HBcrAg and pgRNA in Pregnant Women With Chronic HBV Under Different Disease Phases and Antiviral Prophylaxis

Background

Pregnant women with chronic hepatitis B (CHB) exhibit unique clinical features in terms of postpartum immune system reconstitution and recovery from pregnancy-related changes. However, current studies focus primarily on the outcomes of maternal-infant transmission and postpartum hepatitis flares. We aimed to evaluate the profiles of hepatitis B core-related antigen (HBcrAg) and pregenomic RNA (pgRNA) in pregnant women with CHB.

Methods

This retrospective analysis included treatment-naïve pregnant women with CHB who were followed up regularly in an outpatient clinic from 2014 to 2021. Baseline HBcrAg and pgRNA levels were compared in patients with different disease phases. Changes in these parameters were examined in a subset of patients receiving antiviral prophylaxis. HBcrAg and pgRNA levels were measured before treatment, at 32 weeks of gestation, and postpartum.

Results

The final analysis included a total of 121 patients, 100 of whom were hepatitis B e antigen (HBeAg)-positive (96 and 4 in the immune-tolerant and -indeterminate phases, respectively) and 21 of whom were HBeAg-negative (6 and 15 in the immune-active and -inactive carrier phases, respectively). The HBeAg-negative group vs the HBeAg-positive group had lower levels of baseline HBcrAg (median [interquartile range {IQR}], 3.7 [3.0-5.9] vs 8.6 [8.4-8.7] log10 U/mL; P < .01) and pgRNA (median [IQR], 0.0 [0.0-2.5] vs 7.8 [7.6-8.1] log10 copies/mL; P < .01). The serum levels of HBcrAg and pgRNA were highest in immune-tolerant carriers and lowest in immune-inactive carriers. In HBeAg-positive patients, the correlation coefficients of HBcrAg and pgRNA with hepatitis B virus (HBV) DNA were 0.40 and 0.43, respectively; in HBeAg-negative patients, they were 0.53 and 0.51, respectively (all P < .05). The correlation coefficients with hepatitis B surface antigen (HBsAg) were 0.55 and 0.52 (P < .05) in HBeAg-positive patients, respectively, while in HBeAg-negative patients they were 0.42 and 0.37, respectively (P > .05). Among 96 patients receiving antiviral prophylaxis, we detected a rapid decrease in HBV DNA to an undetectable level during treatment but relatively stable levels of pgRNA and HBcrAg.

Conclusions

HBcrAg and pgRNA levels are lower in HBeAg-negative patients than in HBeAg-positive patients. These 2 markers are significantly associated with HBV DNA irrespective of HBeAg status, while they are significantly associated with HBsAg only in HBeAg-positive patients.

Clinical Significance and Remaining Issues of Anti-HBc Antibody and HBV Core-Related Antigen

Currently, hepatitis B virus (HBV) core antibody (anti-HBc antibody) and HBV core-related antigen (HBcrAg) are widely used as serum markers for diagnosis based on the HBV core region. This review focused on anti-HBc antibodies and HBcrAg and aimed to summarize the clinical significance of currently used assay systems and the issues involved. While anti-HBc is very significant for clinical diagnosis, the clinical significance of quantitative assay of anti-HBc antibody has been reevaluated with improvements in diagnostic performance, including its association with clinical stage and prediction of carcinogenesis and reactivation. In addition, concerning the new HBcrAg, a high-sensitivity assay method has recently been established, and its diagnostic significance, including the prediction of reactivation, is being reevaluated. On the other hand, the quantitative level of anti-HBc antibody expressed in different units among assay systems complicates the interpretation of the results. However, it is difficult to standardize assay systems as they vary in advantages, and caution is needed in interpreting the assay results. In conclusion, with the development of highly sensitive HBcrAg and anti-HBc antibody, a rapid and sensitive detection assay system has been developed and used in clinical practice. In the future, it is hoped that a global standard will be created based on the many clinical findings.

Quantitative Measurement of Serum HBcrAg Can Be Used to Assess the Feasibility of Safe Discontinuation of Antiviral Therapy for Chronic Hepatitis B

Hepatitis B virus (HBV) infection is a serious global health problem, and chronic HBV infection significantly increases the risk of liver fibrosis, cirrhosis, and even hepatocellular carcinoma in patients. Current first-line therapeutics such as nucleos(t)ide analogues and interferons are unable to completely clear cccDNA, so the vast majority of patients need to take long-term or even lifelong medication. However, long-term virological and biochemical responses can be achieved in some patients after drug withdrawal. Successfully screening these patients with drug withdrawal advantages is difficult. Hepatitis-B-core-related antigen (HBcrAg) is a new HBV serological marker that which can reflect the level and transcription activity of cccDNA in hepatocytes. Therefore, HBcrAg has potential value in guiding patients in drug withdrawal. This review summarizes previous reports on HBcrAg and evaluates the application value of HBcrAg in safe drug discontinuation.

Expression and purification of Hepatitis B virus core antigen using Escherichia coli and its utilization for the diagnosis of Hepatitis B virus infections

Hepatitis B virus (HBV) is responsible for most of the viral hepatitis worldwide. HBV is a partially double stranded DNA virus that is composed of four main open reading frames (ORFs) encoding its important antigens, namely hepatitis B surface antigen (HBsAg), hepatitis B core antigen (HBcAg), HBV polymerase and hepatitis B X antigen (HBxAg). In this study, we report a successful method for the cloning and expression of HBcAg. The ORF of HBcAg was successfully amplified using polymerase chain reaction (PCR), cloned into the expression vector pRSET-B and transformed to Escherichia coli (E. coli) BL-21 (DE3) pLysS strain for protein expression. Successful expression of HBcAg was accomplished, in which an induced protein with a molecular weight of 24 kDa was obtained and confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting. The produced HBcAg was successfully used for the diagnosis of HBV infected patient through detection of antibodies against HBcAg (anti-HBcAg) in the serum of the patient utilizing Western blotting. Overall, this study provides a simple, convenient and efficient protocol for the production of HBcAg that can be used as an important candidate to study the diagnosis and prognosis of HBV disease, as well as for understanding the epidemiological prevalence of HBV cases and production of anti-HBcAg.

Use of HBV RNA and to predict change in serological status and disease activity in CHB

BACKGROUND AND AIMS

Predicting changes in disease activity and serological endpoints is necessary for the management of patients with chronic hepatitis B (CHB). We examined whether HBV RNA and hepatitis B core-related antigen (HBcrAg), two specialized virological markers proposed to reflect the activity of covalently closed circular DNA, may improve the ability to predict not sustained inactive carrier phase, spontaneous alanine aminotransferase (ALT) flare, HBeAg loss, and HBsAg loss.

APPROACH AND RESULTS

Among eligible participants enrolled in the North American Hepatitis B Research Network Adult Cohort Study, we evaluated demographic, clinical, and virologic characteristics, including HBV RNA and HBcrAg, to predict not sustained inactive carrier phase, ALT flare, HBeAg loss, and HBsAg loss through a series of Cox proportional hazard or logistic regression models, controlling for antiviral therapy use. Among the study population, 54/103 participants experienced not sustained inactive carrier phase, 41/1006 had a spontaneous ALT flare, 83/250 lost HBeAg, and 54/1127 lost HBsAg. HBV RNA or HBcrAg were predictive of all 4 events. However, their addition to models of the readily available host (age, sex, race/ethnicity), clinical (ALT, use of antiviral therapy), and viral factors (HBV DNA), which had acceptable-excellent accuracy (e.g., AUC = 0.72 for ALT flare, 0.92 for HBeAg loss, and 0.91 for HBsAg loss), provided only small improvements in predictive ability.

CONCLUSION

Given the high predictive ability of readily available markers, HBcrAg and HBV RNA have a limited role in improving the prediction of key serologic and clinical events in patients with CHB.

Hepatitis B core-related antigen: A novel and promising surrogate biomarker to guide anti-hepatitis B virus therapy

The current requirement for biomarkers to detect hepatitis B virus (HBV) infection is polarized. One is a fully-automated and highly sensitive measurement system; the other is a simple system for point-of-care testing (POCT) in resource-limited areas. Hepatitis B core-related antigen (HBcrAg) reflects intrahepatic covalently closed circular DNA and serum HBV DNA. Even in patients with undetectable serum HBV DNA or HBsAg loss, HBcrAg may remain detectable. Decreased HBcrAg levels are associated with reduction of the occurrence of hepatocellular carcinoma (HCC) in chronic hepatitis B. Recently, a fully-automated, novel high-sensitivity HBcrAg assay (iTACT-HBcrAg, cut-off value: 2.1 logIU/mL) has been developed. This attractive assay has been released in Japan very recently. iTACT-HBcrAg can be useful for monitoring HBV reactivation and prediction of HCC occurrence, as an alternative to HBV DNA. Moreover, monitoring HBcrAg may be suitable for determining the therapeutic effectiveness of approved drugs and novel drugs under development. Presently, international guidelines recommend anti-HBV prophylaxis for pregnant women with high viral loads to prevent mother-to-child transmission of HBV. However, >95% of HBV-infected individuals live in countries where HBV DNA quantification is not available. Worldwide elimination of HBV needs the scaling-up of examination and medication services in resource-limited areas. Based on this situation, a rapid and easy HBcrAg assay as a POCT is valuable. This review provides the latest information regarding the clinical use of a new surrogate marker, HBcrAg, in HBV management, based on iTACT-HBcrAg or POCT, and introduces novel agents targeting HBV RNA/protein.

KGHeBTA (King George's Medical University Hepatitis B Therapeutic Algorithm): A New Diagnostic and Therapeutic Algorithm and Clinico-epidemiological Spectrum of Hepatitis B

Background

Diagnostic and therapeutic algorithms given by various societies for hepatitis B are fragmented and complex. The clinico-epidemiologic spectrum of hepatitis B is not studied with large-scale data from our region. We aimed to develop a comprehensive algorithm for the treatment of hepatitis B and study its clinico-epidemiological spectrum.

Methods

From 2014-2019, the clinico-laboratory data of hepatitis B surface antigen (HbsAg)-positive patients were prospectively recorded. King George's Medical University hepatitis B therapeutic algorithm (KGHeBTA) was developed on the basis of the standard existing guidelines. The prevalence of different clinical stages of HBsAg-positive patients was calculated and their treatment records reviewed. Testing circumstances and risk factors were noted.

Results

Among 1,508 data record sheets, 421 were complete. According to the KGHeBTA algorithm, 221 had detectable hepatitis B virus DNA. 21% were cirrhotic and 79% non-cirrhotic. 72% were incidentally detected asymptomatic hepatitis B, 7% were hepatitis B with acute symptoms, 0.7% were acute hepatitis B, and 22% were chronic hepatitis B. 20% patients were eligible for antivirals and 80% patients were not eligible. 32% patients were actually treated with antivirals due to the inclusion of some special indications as pregnancy and family history. Screening during various medical illnesses (40%) was the most common and during health camps (0.2%), the least common testing approach. Road-side shaving (52%) was the most common and intravenous drug abuse (0.2%) and the least common risk factor for the detection of hepatitis B in our data pool.

Conclusions

HBsAg-positive patients can be easily worked up and treated based on the proposed algorithm (KGHeBTA). About one fourth to one fifth of all HBsAg-positive patients were eligible and treated with oral antivirals. Most of the patients were incidentally detected asymptomatic hepatitis B screened during medical illnesses. Roadside shaving and intravenous drug abuse were the most and the least common risk factors.

Lower end of treatment HBsAg and HBcrAg were associated with HBsAg loss after nucleos(t)ide analog cessation

BACKGROUND

Since hepatitis B surface antigen (HBsAg) loss is rarely achieved with nucleos(t)ide analog (NA) treatment, most patients require life-long NA treatment. Previous studies have shown that some patients remain virologically responsive even after NA cessation. However, there is still controversy surrounding whether NA discontinuation increases the HBsAg loss rate. Therefore, this study aimed to assess the cumulative rate of HBsAg loss and identify the predictors of HBsAg loss after NA discontinuation.

METHODS

This multicenter prospective study included HBV e antigen (HBeAg)-positive patients without cirrhosis from 12 hospitals in China who met the inclusion criteria. The enrolled patients stopped NA and were followed up with clinical and laboratory assessments every 3 months for 24 months after NA cessation or until clinical relapse (CR) occurred.

RESULTS

Overall, 158 patients were classified into two groups. Group A included patients with HBsAg positivity at NA cessation (n = 139), and Group B included patients with HBsAg negativity at NA cessation (n = 19). In Group A, the 12-month and 24-month cumulative rates of HBsAg loss were4.3%and 9.4%, respectively. End of treatment (EOT) HBsAg (hazard ratio (HR) = 0.152, P < 0.001) and EOT hepatitis B core-related antigen (HBcrAg) (HR = 0.257, P = 0.001) were associated with HBsAg loss. The areas under the receiver operating characteristic curves for EOT HBsAg and HBcrAg levels were 0.952 (P < 0.001) and 0.765 (P < 0.001), respectively. Patients with EOT HBsAg ≤ 135 IU/mL (59.2% vs. 1.3%, P < 0.001) or HBcrAg ≤ 3.6 logU/mL (17% vs. 5.4%, P = 0.027) had a higher 24-month cumulative HBsAg loss rate. In Group B, none of the patients experienced virological relapse after NA cessation. Only 1 (5.3%) patient had HBsAg reversion.

CONCLUSIONS

EOT HBsAg ≤ 135 IU/mL or HBcrAg ≤ 3.6 logU/mL can be used to identify patients with a higher likelihood of HBsAg loss after NA cessation. Patients with HBsAg negativity after NA cessation have favorable clinical outcomes, and HBsAg loss was durable in most cases.

A critique and systematic review of the clinical utility of hepatitis B core-related antigen

BACKGROUND & AIMS

Hepatitis B core-related antigen (HBcrAg) is a new biomarker for chronic hepatitis B (CHB) whose performance has not been critically or systematically appraised. Herein, we performed a systematic review to determine its clinical utility.

METHODS

We evaluated the biological pathway of HBcrAg and performed a systematic review of PubMed for clinical trials, cohort studies, and case-control studies that evaluated the clinical utility of HBcrAg. The effectiveness of HBcrAg in predicting HBV-specific clinical events (e.g. HBeAg seroconversion, phases of CHB, HBsAg loss, treatment response, and relapse after stopping therapy) was examined using receiver-operating characteristic curves. The correlation coefficients of HBcrAg with HBV DNA, quantitative HBsAg (qHBsAg), HBV RNA, and cccDNA were summarised from published studies. Median values were used as estimates.

RESULTS

HBcrAg consists of three precore/core protein products: HBcAg, HBeAg, and a 22 kDa precore protein. HBcrAg assays have been associated with false-positive rates of 9.3% and false-negative rates of between 12-35% for CHB. The new iTACT-HBcrAg is more sensitive but does not reduce the false-positive rate. A PubMed search found 248 papers on HBcrAg, of which 59 were suitable for analysis. The clinical performance of HBcrAg was evaluated using AUROC analyses, with median AUROCs of 0.860 for HBeAg seroconversion, 0.867 for predicting HBeAg(-) hepatitis, 0.645 for HBsAg loss, 0.757 for treatment response, and 0.688 for relapse after stopping therapy. The median correlation coefficient (r) was 0.630 with HBV DNA, 0.414 with qHBsAg, 0.619 with HBV RNA and 0.550 with cccDNA. Correlation decreased during antiviral therapy, but combined biomarkers improved performance.

CONCLUSIONS

HBcrAg has a mixed performance and has a poor correlation with HBsAg loss and antiviral therapy, hence HBcrAg results should be interpreted with caution.

IMPACT AND IMPLICATIONS

Hepatitis B core-related antigen (HBcrAg) has been used to assess management of patients with chronic hepatitis B (CHB) without a systematic and critical Sreview of its performance. Our finding that HBcrAg had a false-positive rate of 9% and a false-negative rate of 12-35% raises concerns, although larger studies are needed for validation. A systematic review showed that the performance of HBcrAg was variable depending on the CHB endpoint; it was excellent at predicting HBeAg seroconversion and HBeAg-negative chronic hepatitis (vs. chronic infection), which should be its main use, but it was poor for relapse after stopping antiviral therapy and for HBsAg loss. HBcrAg results should be interpreted with considerable caution, particularly by physicians, researchers, guideline committees and agencies that approve diagnostic tests.

A longitudinal study to detect hepatitis B surface and core-related antigens in chronic hepatitis B patients with hepatitis B surface antigen seroclearance using highly sensitive assays

BACKGROUND

This study aimed to evaluate the usefulness of two novel assays, namely the iTACT-hepatitis B surface antigen (iTACT-HBsAg) and iTACT-hepatitis B core-related antigen (iTACT-HBcrAg) assays, in chronic hepatitis B (CHB) patients with HBsAg seroclearance (SC) documented by standard assays.

METHODS

HBsAg and HBcrAg were measured by the two iTACT-assays in 556 serial sera collected from 96 CHB patients at 7 different time points spanning from 5 years before to 10 years after SC and 120 HBsAg-negative, anti-HBc-positive individuals. As controls, 60 seronegative individuals, who were negative for HBsAg, anti-HBc and anti-HBs, were tested.

RESULTS

Using the iTACT-assays, HBsAg was detectable in 154/418 (36.8%) samples collected after SC. HBcrAg was detectable in 78.3% and 65.9% of samples collected before and after SC, respectively. The detectability rates of both HBsAg and HBcrAg progressively decreased over time after SC. At 10 years after SC, 20.4% and 64.5% of the patients still had detectable HBsAg and HBcrAg, respectively. 66 (71%) patients had detectable HBsAg and/or HBcrAg. Among the 120 HBsAg-negative, anti-HBc-positive individuals, 11 (9.2%) and 4 (3.3%) had detectable HBsAg and HBcrAg respectively. Both HBsAg and HBcrAg were undetectable in the controls.

CONCLUSION

The iTACT assays detected a low level of HBsAg and/or HBcrAg in >70% of patients even at 10 years after SC, suggesting that CHB patients with SC still harbour a low level of HBV protein expression. The clinical significance of detectable viral proteins after SC with regard to disease progression and HBV reactivation deserves further investigations.

Current Challenges and Future Perspectives of Diagnosis of Hepatitis B Virus

It is estimated that approximately 260 million people worldwide are infected with the hepatitis B virus (HBV), which is one of the leading causes of liver disease and liver cancer throughout the world. Compared with developed countries, low-income and middle-income countries have limited access to resources and advanced technologies that require highly specialized staff for HBV diagnosis. In spite of the heavy burden caused by hepatitis B virus, 90% of people are still undiagnosed. The World Health Organization (WHO) goal of eliminating hepatitis B by 2030 seems very difficult to achieve due to the existing diagnostic infrastructure in low-resource regions. The majority of diagnostic laboratories still use hepatitis B surface antigen (HBsAg)-based tests. WHO's elimination plan is at risk of derailment due to phases like the window period, immune control, and occult HBV infection (OBI) not being detected by standard tests. Here, in this article, we are focusing on various diagnostic platforms for the better diagnosis of HBV. The aim of the elimination of HBV can only be achieved by detecting all phases of HBV infection, which can be executed by a combined approach of using new marker assays along with advanced pretesting and testing methods.

Hepatitis B virus pre-genomic RNA and hepatitis B core-related antigen reductions at week 4 predict favourable hepatitis B surface antigen response upon long-term nucleos(t)ide analogue in chronic hepatitis B

BACKGROUND/AIMS

We investigated the dynamics of serum HBV pre-genomic RNA (pgRNA) and hepatitis B core-related antigen (HBcrAg) in patients receiving nucleos(t)ide analogues (NAs) and their predictability for favourable suppression of serum hepatitis B surface antigen (HBsAg).

METHODS

Serum viral biomarkers were measured at baseline, weeks 4, 12, 24, 36, and 48 of treatment. Patients were followed up thereafter and serum HBsAg level was measured at end of follow-up (EOFU). Favourable HBsAg response (FHR) was defined as ≤100 IU/mL or HBsAg seroclearance upon EOFU.

RESULTS

Twenty-eight hepatitis B e antigen (HBeAg)-positive and 36 HBeAg-negative patients (median, 38.2 years old; 71.9% male) were recruited with median follow-up duration of 17.1 years (interquartile range, 12.8-18.2). For the entire cohort, 22/64 (34.4%) achieved FHR. For HBeAg-positive patients, serum HBV pgRNA decline at week 4 was significantly greater for patients with FHR compared to non-FHR (5.49 vs. 4.32 log copies/mL, respectively; P=0.016). The area under the receiver-operating-characteristic curve (AUROC) for week 4 HBV pgRNA reduction to predict FHR in HBeAg-positive patients was 0.825 (95% confidence interval [CI], 0.661-0.989). For HBeAg-negative patients, instead of increase in serum HBcrAg in non-FHR patients, FHR patients had median reduction in HBcrAg at week 4 (increment of 1.75 vs. reduction of 2.98 log U/mL; P=0.023). The AUROC for week 4 change of HBcrAg to predict FHR in HBeAg-negative patients was 0.789 (95% CI, 0.596-0.982).

CONCLUSION

Early on-treatment changes of serum HBV pgRNA and HBcrAg at 4 weeks predict HBsAg seroclearance or ≤100 IU/mL in NA-treated CHB patients upon long-term FU.

Hepatitis delta virus: Disease assessment and stratification

Hepatitis D virus (HDV) causes one of the most severe forms of hepatitis in people with chronic hepatitis B (CHB) infection. Timely and accurate assessment of hepatitis delta virus (HDV) and disease stratification is mandatory for thorough pre-therapeutic evaluation for prioritizing treatment and outcome prediction. Viral biomarkers associated with HDV and hepatitis B virus (HBV) are crucial to aid in diagnosis, and monitoring of serum viral nucleic acids for both viruses is recommended. Liver biopsy remains the gold standard for staging of liver fibrosis and grading of histological activity and should remain central for diagnostic purposes, but is also of importance for research to enhance our understanding of HDV. The emergence of novel non-invasive tests for the assessment of liver fibrosis in HDV patients coupled with the well-recognized potential complications of liver biopsy has resulted in reduced utility of liver biopsy in clinical practice. Preliminary data suggest that these emerging non-invasive modalities appear to be reliable, and their use is supported, similar to other viral hepatitis. Nevertheless, further validation is required before their widespread adoption into clinical practice.

Low anti-HBc levels are associated with lower risk of virological relapse after nucleos(t)ide analogue cessation in HBe antigen-negative patients

BACKGROUND AND AIMS

Low anti-HBc serum levels at the time of therapy cessation were linked to a higher relapse risk in predominantly HBeAg-positive cohorts. We investigated the association of anti-HBc levels with relapse in HBeAg-negative patients.

METHODS

Serum levels of anti-HBc, HBsAg and HBcrAg were determined in 136 HBeAg-negative patients, participating in a vaccination trial (ABX-203, NCT02249988), before treatment cessation or vaccination. Importantly, vaccination showed no impact on relapse. The correlation between the biomarkers and their predictive value for relapse (HBV DNA >2000 IU/ml ± ALT >2xULN) was investigated.

RESULTS

After therapy cessation 50% (N = 68) of patients relapsed. Median anti-HBc prior to treatment stop was significantly higher among relapsers compared to off-treatment responders (520 IU/ml vs. 330 IU/mL, p = .0098). The optimal anti-HBc cut-off to predict relapse was 325 IU/ml according to the Youden-Index. About 35% of patients with anti-HBc level < 325 IU/ml versus 60% of those with values ≥325 IU/mL relapsed (p = .0103; sensitivity 50%, specificity 75%). Combining the optimal cut-offs of HBsAg (>3008 IU/mL) or HBcrAg (≥1790 U/ml) with anti-HBc increased the proportion of patients with relapse to 80% (p < .0001) and 74% (p = .0006), respectively.

CONCLUSION

In contrast to predominantly HBeAg-positive cohorts, in our cohort of HBeAg-negative patients lower anti-HBc levels are associated with a significantly lower relapse risk after nucleos(t)ide analogue cessation. The vast majority of included patients were either genotype B or C and the applicability to other genotypes has to be further evaluated. However, anti-HBc level as an indicator of the host response might be prospectively further explored for prediction models.

HBcrAg Predicts Hepatocellular Carcinoma Development in Chronic B Hepatitis Related Liver Cirrhosis Patients Undergoing Long-Term Effective Anti-Viral

Hepatitis B core-related antigen (HBcrAg) is a predictor of hepatocellular carcinoma (HCC) in chronic hepatitis B (CHB) patients. Studies on anti-viral therapy have shown that the use of NUC therapy in HBV patients could reduce the incidence of HCC. However, the incidence of HCC continues to increase after long-term anti-viral therapy. The relationship between HBcrAg and HCC development in CHB-related liver cirrhosis (LC) patients undergoing long-term anti-viral therapy is still unclear. This study enrolled 1108 treatment-naïve CHB patients diagnosed with HBV-related LC receiving NUC therapy from April 1999 to February 2015. The baseline biomarkers, disease history, and following results were collected by the hospital. Among the 1108 patients, 219 developed HCC within a median follow-up period of 6.85 years. A multivariable Cox regression model was used, with adjustment for age, gender, FIB-4, DM, and HBsAg-HQ. The adjusted hazard ratios for the HBcrAg tertile levels were 1.70 (95%CI: 1.21, 2.39) and 2.14 (95%CI: 1.50, 3.05) for levels 3.4-4.9 and >4.9 logU/mL, respectively, compared with levels ≤3.4. The effect of the HBcrAg level on HCC incidence was found to be significantly modified by HBsAg-HQ, where lower HBsAg-HQ (≤ 3) values were associated with a significantly higher risk, but HBsAg-HQ levels >3 were not. Our results highlight that, after adjustment for potential confounding factors, patients with CHB-related LC and higher HBcrAg levels are at significant risk for HCC development, even while undergoing long-term effective anti-viral therapy. The HBcrAg level is therefore an independent risk factor for HCC development, especially for patients with HBsAg-HQ levels <3.

A roadmap for serum biomarkers for hepatitis B virus: current status and future outlook

Globally, 296 million people are infected with hepatitis B virus (HBV), and approximately one million people die annually from HBV-related causes, including liver cancer. Although there is a preventative vaccine and antiviral therapies suppressing HBV replication, there is no cure. Intensive efforts are under way to develop curative HBV therapies. Currently, only a few biomarkers are available for monitoring or predicting HBV disease progression and treatment response. As new therapies become available, new biomarkers to monitor viral and host responses are urgently needed. In October 2020, the International Coalition to Eliminate Hepatitis B Virus (ICE-HBV) held a virtual and interactive workshop on HBV biomarkers endorsed by the International HBV Meeting. Various stakeholders from academia, clinical practice and the pharmaceutical industry, with complementary expertise, presented and participated in panel discussions. The clinical utility of both classic and emerging viral and immunological serum biomarkers with respect to the course of infection, disease progression, and response to current and emerging treatments was appraised. The latest advances were discussed, and knowledge gaps in understanding and interpretation of HBV biomarkers were identified. This Roadmap summarizes the strengths, weaknesses, opportunities and challenges of HBV biomarkers.

Clinical significance of novel biomarkers to predict the natural course of hepatitis B infection

Background and aim

Chronic hepatitis B (CHB) can be divided into immune tolerance (IT), immune clearance (IC), hepatitis B e antigen (HBeAg)-negative inactive/quiescent carrier (ENQ), and HBeAg-negative hepatitis (ENH) phases. The conventional biomarkers used to distinguish these phases have limitations. We examined the clinical significance of hepatitis B virus (HBV) RNA and hepatitis B core-related antigen (HBcrAg) as novel biomarkers.

Methods

One hundred eighty-nine patients without treatment currently were categorized by CHB phase (IT = 46, IC = 45, ENQ = 49, ENH = 49). The associations of HBV RNA and HBcrAg with HBV DNA and alanine transaminase (ALT) were analyzed. The decision tree model was used to distinguish the four phases in the natural course of CHB.

Results

The concentrations of HBV RNA and HBcrAg were highest in the IT and IC phases (P < 0.01). Serum HBV RNA was similar to HBcrAg in treatment-naïve patients. HBV RNA and HBcrAg correlated with HBV DNA in the HBeAg⁺ and HBeAg^- status (HBV RNA: e⁺ r = 0.51, e^- r = 0.62; HBcrAg: e⁺ r = 0.51, e^- r = 0.71), but their association with HBV DNA differed among phases. The accuracy, sensitivity, and specificity of HBcrAg with ALT in distinguishing the CHB phases were 95.65%, 95.83%, and 95.55%, respectively.

Conclusion

Serum HBV RNA and HBcrAg may be useful to monitor CHB progression.

A Mac-2 Binding Protein Glycosylation Isomer-Based Risk Model Predicts Hepatocellular Carcinoma in HBV-Related Cirrhotic Patients on Antiviral Therapy

Mac-2 binding protein glycosylation isomer (M2BPGi) has not been used in a risk score to predict hepatocellular carcinoma (HCC). We enrolled 1003 patients with chronic hepatitis B and cirrhosis receiving entecavir or tenofovir therapy for more than12 months to construct an HCC risk score. In the development cohort, Cox regression analysis identified male gender, age, platelet count, AFP and M2BPGi levels at 12 months of treatment as independent risk factors of HCC. We developed the HCC risk prediction model, the ASPAM-B score, based on age, sex, platelet count, AFP and M2BPGi levels at 12 months of treatment, with the total scores ranging from 0 to 11.5. This risk model accurately classified patients into low (0−3.5), medium (4−7), and high (>7) risk in the development and validation groups (p < 0.001). The areas under the receiver operating characteristic curve (AUROC) of 3-, 5- and 9-year risks of HCC were 0.742, 0.728 and 0.719, respectively, in the development cohort. All AUROC between the ASPAM-B and APA-B, PAGE-B, RWS-HCC and THRI scores at 3−9 years were significantly different. The M2BPGi-based risk model exhibited good discriminant function in predicting HCC in cirrhotic patients who received long-term antiviral treatment.

Correlations between serum hepatitis B core-related antigen and hepatitis B surface antigen in patients with hepatitis B cirrhosis and a hepatitis B virus-DNA-negative status: a retrospective study

OBJECTIVE

This study aimed to examine the correlations between serum hepatitis B core-related antigen (HBcrAg) and hepatitis B surface antigen (HBsAg) titers in patients with hepatitis B cirrhosis and a hepatitis B virus (HBV)-DNA-negative status.

METHODS

We retrospectively analyzed the data and blood samples of patients who were diagnosed with HBV liver cirrhosis and an HBV-DNA negative status. These patients were hospitalized between October 2018 and October 2019 at one hospital.

RESULTS

A total of 180 patients were included. The median (interquartile range) HBsAg and HBcrAg concentrations were 2.77 log₁₀ IU/mL (1.60-3.15) and 3.96 log₁₀ U/mL (2.70-4.97), respectively. A non-linear significant relationship was found between HBsAg and HBcrAg concentrations. The inflection point was 0.58. The effect size and confidence interval on the left and right sides of the inflection point were 0.10 (-0.23-0.42) and 0.62 (0.46-0.78), respectively. When HBsAg concentrations were ≥0.58 log₁₀ IU/mL, HBsAg concentrations were positively correlated with HBcrAg concentrations. When HBsAg concentrations increased by 1 log₁₀ IU/mL, HBcrAg concentrations increased by 0.62 log₁₀ U/mL (95% confidence interval: 0.46, 0.78).

CONCLUSIONS

There might be a non-linear relationship between HBcrAg and HBsAg concentrations in patients with hepatitis B cirrhosis and an HBV-DNA-negative status.

Review article: novel biomarkers in hepatitis B infection

BACKGROUND

Chronic hepatitis B remains a global health problem with an estimated 296 million people affected worldwide. Individuals are at risk of serious complications such as cirrhosis and hepatocellular carcinoma and accurately predicting these clinical endpoints has proven difficult. However, several viral biomarkers have recently been developed, including quantitative HBV surface antigen (qHBsAg), hepatitis B RNA (HBV RNA) and core-related antigen (HBcrAg), and shown promise in a range of clinical settings.

AIMS

To critically appraise these novel biomarkers, exploring their potential uses, availability of assays and areas for future development.

METHODS

We performed a literature search of PubMed, identifying articles published in the field of hepatitis B biomarkers between 2010 and 2022.

RESULTS

Novel biomarkers such as HBcrAg, HBV RNA and qHBsAg may be useful in predicting treatment outcomes, stratifying the risk of future complications and estimating off-treatment viral reactivation. Furthermore, HBV RNA and HBcrAg titres may accurately reflect cccDNA transcriptional activity, and this is particularly informative in the context of nucleoside analogue therapy. On a cautionary note, most studies have been performed in Caucasian or Asian populations, and methods for detecting HBV RNA lack standardisation.

CONCLUSION

Novel viral biomarkers have the potential to provide additional insights into the natural history of infection and allow a more bespoke, cost-effective framework of care. However, access remains limited, and further efforts are needed to validate their use in ethnically diverse populations, confirm predictive cut-off values, and establish their role in the era of novel antiviral therapies.

Surrogate Markers for Hepatitis B Virus Covalently Closed Circular DNA

Chronic infection with the hepatitis B virus (HBV) is one of the most common causes of liver disease worldwide. Chronic HBV infection is currently incurable because of the persistence of the viral template for the viral transcripts, covalently closed circular deoxyribonucleic acid (cccDNA). Detecting changes in cccDNA transcriptional activity is key to understanding fundamental virology, determining the efficacy of new therapies, and deciding the optimal clinical management of HBV patients. In this review, we summarize surrogate circulating biomarkers that have been used to infer cccDNA levels and activity in people with chronic hepatitis B. Moreover, we outline the current shortcomings of the current biomarkers and highlight the clinical importance in improving them and expanding their use.

Capabilities of hepatitis B surface antigen are divergent from hepatitis B virus DNA in delimiting natural history phases of chronic hepatitis B virus infection

Objective

Quantitative hepatitis B surface antigen (HBsAg) and hepatitis B virus (HBV) DNA in the natural history of chronic HBV infection have not been rationally evaluated. This study aimed to re-characterize quantitative HBsAg and HBV DNA in the natural history phases.

Methods

A total of 595 and 651 hepatitis B e antigen (HBeAg)-positive patients and 485 and 705 HBeAg-negative patients were assigned to the early and late cohorts, respectively. Based on the ‘S-shape’ receiver operating characteristic (ROC) curves, the HBeAg-positive sub-cohorts with possibly high HBV replication (PHVR) and possibly low HBV replication (PLVR) and the HBeAg-negative sub-cohorts with possibly high HBsAg expression (PHSE) and possibly low HBsAg expression (PLSE) were designated.

Results

The areas under the ROC curve (AUCs) of HBsAg and HBV DNA in predicting HBeAg-positive significant hepatitis activity (SHA) in the early cohort, sub-cohort with PHVR, and sub-cohort with PLVR were 0.655 and 0.541, 0.720 and 0.606, and 0.553 and 0.725, respectively; those in the late cohort, sub-cohort with PHVR, and sub-cohort with PLVR were 0.646 and 0.501, 0.798 and 0.622, and 0.603 and 0.674, respectively. The AUCs of HBsAg and HBV DNA in predicting HBeAg-negative SHA in the early cohort, sub-cohort with PHSE, and sub-cohort with PLSE were 0.508 and 0.745, 0.573 and 0.780, and 0.577 and 0.729, respectively; those in the late cohort, sub-cohort with PHSE, and sub-cohort with PLSE were 0.503 and 0.761, 0.560 and 0.814, and 0.544 and 0.722, respectively. The sensitivity and specificity of HBsAg ≤4.602 log10 IU/ml in predicting HBeAg-positive SHA in the early cohort were 82.6% and 45.8%, respectively; those in the late cohort were 87.0% and 44.1%, respectively. The sensitivity and specificity of HBV DNA &gt;3.301 log10 IU/ml in predicting HBeAg-negative SHA in the early cohort were 73.4% and 60.8%, respectively; those in the late cohort were 73.6% and 64.1%, respectively.

Conclusion

Quantitative HBsAg and HBV DNA are valuable, but their capabilities are divergent in delimiting the natural history phases.

Hepatitis B core-related antigen: Are we near a treatment endpoint?

Different serological and virological markers in chronic hepatitis B patients guide staging of viral infection, and initiation and response to therapy. Due to the persistence of intrahepatic covalently closed circular DNA (cccDNA) in the hepatocyte nucleus, hepatitis B is not curable. Even after undetectable hepatitis B virus DNA levels, the persistence of hepatitis B surface antigen and novel markers such as hepatitis B core-related antigen (HBcrAg) indicate the persistence of intrahepatic cccDNA. In this study, HBcrAg levels at baseline and after 24 and 48 wk of antiviral therapy predicted hepatitis B e antigen seroconversion. Due to the poor sensitivity of assays and detectable levels in HBsAg-negative patients, the long-term utility of HBcrAg needs future research.

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.

Getting to HBV cure: The promising paths forward

Chronic HBV infection is a global public health burden estimated to impact nearly 300 million persons worldwide. Despite the advent of potent antiviral agents that effectively suppress viral replication, HBV cure remains difficult to achieve because of the persistence of covalently closed circular DNA (cccDNA), HBV-DNA integration into the host genome, and impaired immune response. Indefinite treatment is necessary for most patients to maintain level of viral suppression. The success of direct-acting antivirals (DAAs) for hepatitis C treatment has rejuvenated the search for a cure for chronic hepatitis B (CHB), though an HBV cure likely requires an additional layer: immunomodulators for restoration of robust immune responses. DAAs such as entry inhibitors, capsid assembly modulators, inhibitors of subviral particle release, cccDNA silencers, and RNA interference molecules have reached clinical development. Immunomodulators, namely innate immunomodulators (Toll-like receptor agonists), therapeutic vaccines, checkpoint inhibitors, and monoclonal antibodies, are also progressing toward clinical development. The future of the HBV cure possibly lies in triple combination therapies with concerted action on replication inhibition, antigen reduction, and immune stimulation. Many obstacles remain, such as overcoming translational failures, choosing the right endpoint using the right biomarkers, and leveraging current treatments in combination regimens to enhance response rates. This review gives an overview of the current therapies for CHB, HBV biomarkers used to evaluate treatment response, and development of DAAs and immune-targeting drugs and discusses the limitations and unanswered questions on the journey to an HBV cure.

Serum Pregenomic RNA Combined With Hepatitis B Core-Related Antigen Helps Predict the Risk of Virological Relapse After Discontinuation of Nucleos(t)ide Analogs in Patients With Chronic Hepatitis B

Background and Aim

Cessation of nucleos(t)ide analogs (NAs) therapy in patients with chronic hepatitis B (CHB) is uncommon. Although criteria for discontinuation appear in some guidelines, the indicators for assessing discontinuation of NAs are limited, whether NAs can be safely ceased remains a difficult clinical issue. Our study aimed to investigate the role of serum pregenomic RNA (pgRNA) and hepatitis B core-related antigen (HBcrAg) at the end of treatment (EOT) in guiding the safe discontinuation of NAs in CHB patients.

Methods

This is a retrospective study, clinical data of all CHB patients who discontinued NAs treatment at West China Hospital between June 2020 and January 2021 were collected, including EOT pgRNA, HBcrAg, hepatitis B surface antigen (HBsAg), etc. All patients should meet the Asian-Pacific guideline for discontinuation. Observing virological relapse (VR) rates during 1 year of NAs discontinuation and analyzing the relationship between EOT pgRNA, HBcrAg, and VR.

Results

A total of 64 patients were enrolled in this study and 33 (51.5%) patients experienced VR in 1 year. EOT pgRNA positivity (OR = 14.59, p = 0.026) and EOT higher HBcrAg levels (OR = 14.14, p = 0.001) were independent risk factors for VR. The area under the receiver-operating characteristic (AUROC) value of EOT HBcrAg for VR was 0.817 (p < 0.001), optimal cut-off value was 3.3 log10 U/mL. Patients with EOT pgRNA positivity and EOT HBcrAg >3.3 log10 U/mL were more likely to experience VR after discontinuation of NAs (88.9 vs. 45.5%, p = 0.027).

Conclusion

According to current guidelines, a higher VR rate occurs after cessation of NAs. EOT pgRNA positivity and higher HBcrAg level carries a higher risk of VR. Combining these novel markers can better help us assess whether patients can safely cease NAs treatment.

Kinetics in HBsAg after Stopping Entecavir or Tenofovir in Patients with Virological Relapse but Not Clinical Relapse

This study investigated the kinetics in HBsAg and the HBsAg loss rate after entecavir or tenofovir disoproxil fumarate (TDF) cessation in patients with chronic hepatitis B (CHB) who achieved virological suppression after virological relapse without clinical relapse. A total 504 HBeAg-negative, non-cirrhotic patients who previously received entecavir or TDF with post-treatment and who were followed up for at least 30 months were included. Of the 504 patients, 128 achieved sustained virological suppression (Group I), and 81 experienced virological relapse without clinical relapse. Of the 81 patients, 52 had intermittent or persistent HBV DNA > 2000 IU/mL (Group II), and 29 achieved persistent virological suppression (HBV DNA < 2000 IU/mL) for at least 1.5 years (Group III) after virological relapse. A generalized estimating equations analysis showed that Groups I and III experienced larger off-treatment HBsAg declines than Group II (both, p < 0.001). The post-treatment HBsAg declines of Group I and Group III were similar (p = 0.414). A multivariate analysis showed that there were no differences in the HBsAg change and HBsAg decline (p = 0.920 and 0.886, respectively) or HBsAg loss rate (p = 0.192) between Group I and Group III. The patients who achieved persistent viral suppression after HBV relapse without clinical relapse have a similar decline in HBsAg and the HBsAg loss rate as the sustained responders.

Impact of HCV viremia on HBV biomarkers in patients coinfected with HBV and HCV

BACKGROUNDS

Hepatitis B virus (HBV) biomarkers reflect the status of HBV infection; however, their role in patients with chronic hepatitis B and C (HBV/HCV) coinfection remains unknown. This study evaluated the characteristics of HBV biomarkers in patients with chronic HBV/HCV coinfection.

METHODS

One hundred untreated HBV/HCV coinfected patients were enrolled. Active viral infection was defined as viral load above 2000 U/L and 15 U/L for HBV and HCV, respectively. Blood samples were analyzed for HBV biomarkers, including hepatitis B surface antigen (HBsAg), hepatitis B core-related antigen (HBcrAg), HBV DNA, and HBV pregenomic RNA (HBV pgRNA). The impact of HCV viremia was also studied.

RESULTS

A total of 15 patients were HBV-inactive/HCV-inactive, 63 patients were HBV-inactive/HCV-active, 14 patients were HBV-active/HCV-inactive and 8 patients were HBV-active/HCV-active. A total of 71 (71%) patients were active HCV and 22 (22%) were active HBV. HBsAg, HBcrAg, and HBV DNA correlated with each other (P < 0.001). HBV pgRNA displayed no correlations with HBV DNA, HBsAg, or HBcrAg. Patients with HCV viremia had significantly lower HBV DNA, HBsAg, and HBcrAg levels as well as higher HBV pgRNA levels and lower HBV DNA:pgRNA ratio than those without viremia (HBV DNA, P < 0.001; HBsAg, P = 0.015; HBcrAg, P = 0.006; HBV pgRNA, P = 0.073; and HBV DNA:pgRNA ratio, P < 0.001).

CONCLUSIONS

In patients coinfected with HBV and HCV, HBsAg, HBcrAg, and HBV DNA significantly correlated with each other. HBV and HCV coinfected patients with HCV viremia have lower HBV DNA, HBsAg, HBcrAg, and HBV DNA:pgRNA ratio as well as higher HBV pgRNA levels.

Hepatitis B Core-Related Antigen Is Useful for Predicting Phase and Prognosis of Hepatitis B e Antigen-Positive Patients

The role of hepatitis B core-related antigen (HBcrAg) level in defining clinical phase and predicting prognosis of chronic hepatitis B (CHB) has not been fully studied. CHB patients who had undergone liver biopsy in Korea University Medical Center were included. Patients with liver cirrhosis were excluded. The associations of HBcrAg level with CHB phase, and nucleos(t)ide analogue (NA)-induced hepatitis B e antigen (HBeAg) seroconversion were analyzed. In total, 387 patients (median follow-up of 82.4 months) were included. The CHB phases of patients were defined histologically as immune-tolerant (IT, n = 32, 8.3%), HBeAg-positive and immune-active (PIA, n = 211, 54.5%), HBeAg-negative and immune-active (n = 125, 32.3%), and inactive (n = 19, 4.9%), respectively. In HBeAg-positive patients, the mean HBV DNA levels were comparable between the two groups (p = 0.990). However, the mean HBsAg (7.4 log IU/mL and 6.9 log IU/mL, p = 0.002) and HBcrAg levels (8.2 log U/mL vs. 7.6 log U/mL, p < 0.001) of IT patients were significantly higher than that of PIA patients. In multivariate analysis, younger age (odds ratio [OR] 0.949, p = 0.025), lower alanine aminotransferase (OR 0.988, p = 0.002) and higher HBcrAg level (OR = 2.745 p = 0.022) were independent predictors of the IT phase. Of the patients in the PIA phase, 194 received NA after liver biopsy, and 61 (31.4%) had achieved HBeAg seroconversion after antiviral therapy. In Cox regression analysis, the higher HBcrAg level was the only independent predictor of the NA-induced HBeAg seroconversion (hazard ratio 1.285, p = 0.028). The HBcrAg level is useful for predicting clinical phase of CHB and NA-induced HBeAg seroconversion in HBeAg-positive patients.

HBcrAg Levels Are Associated With Virological Response to Treatment With Interferon in Patients With Hepatitis Delta

Standard treatment of hepatitis delta virus (HDV) infection remains pegylated-interferon alfa (peg-IFNα) in most centers, which is not only associated with rather low efficacy but several adverse events. Hepatitis B core-related antigen (HBcrAg) is linked to intrahepatic covalently closed circular DNA levels and has previously been suggested as response predictor in IFN-based treatment of hepatitis B virus (HBV) mono-infection. This study aimed to investigate the value of HBcrAg in the management of patients with HBV/HDV co-infection undergoing peg-IFNα treatment. The Hep-Net-International-Delta-Hepatitis-Intervention Trial-2 study included 120 patients co-infected with HBV/HDV. Patients were treated for 96 weeks with peg-IFNα and either tenofovir or placebo. Ninety-nine patients with HDV-RNA results 24 weeks after end of treatment (FU24) were included in this analysis, of whom 32 patients (32.3%) had undetectable HDV RNA at FU24. HBcrAg was measured at baseline, week 12, 24, 48, 96, and FU24. HBcrAg levels showed no significant correlation with HDV RNA but were significantly linked to treatment outcome. HBcrAg levels < 4.5 log IU/mL at baseline, week 24, and week 48 had high negative predictive value (NPV) for achieving undetectable HDV RNA at FU24 (81.8%, 87.1% and 95.0%, respectively). Similarly, HBcrAg levels at week 96 were significantly higher in patients with viral relapse until FU24 (3.0 vs. 3.63 log IU/mL; P = 0.0089). Baseline, week 24, and week 48 HBcrAg levels were also associated with the likelihood of achieving HBsAg level < 100 IU/mL at FU24 (HBcrAg < 3.0 log IU/mL: NPV 91.7%, 90.4% and 92.3%, respectively). Test statistics improved when combining HBcrAg with additional viral and clinical parameters. Conclusion: HBcrAg is linked to treatment response to peg-IFNα in patients with HBV/HDV co-infection and could be a promising marker to determine treatment futility.

Current laboratory tests for diagnosis of hepatitis B virus infection

BACKGROUND

Hepatitis B virus (HBV) has a long history in human infectious diseases. HBV infection can progress chronically, leading to cancer. After introduction of a vaccine, the overall incidence rate of HBV infection has decreased, although it remains a health problem in many countries.

PURPOSE

The aim of this review was to summarise current diagnostic efforts for HBV infection and future HBV diagnosis perspectives.

METHODS

We reviewed and summarised current laboratory diagnosis related with HBV infection in clinical practice.

RESULTS

There have been various serologic- and molecular-based methods to diagnose acute or chronic HBV infection. Since intrahepatic covalently closed circular DNAs (cccDNAs) function as robust HBV replication templates, cure of chronic HBV infection is limited. Recently, new biomarkers such as hepatitis B virus core-related antigen (HBcrAg) and HBV RNA have emerged that appear to reflect intrahepatic cccDNA status. These new biomarkers should be validated before clinical usage.

CONCLUSION

An effective diagnostic approach and current updated knowledge of treatment response monitoring are important for HBV infection management. Brand new ultrasensitive and accurate immunologic methods may pave the way to manage HBV infection in parallel with immunotherapy era.

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.

Comparison of HBV RNA and Hepatitis B Core Related Antigen With Conventional HBV Markers Among Untreated Adults With Chronic Hepatitis B in North America

BACKGROUND AND AIMS

The clinical utility of two biomarkers, hepatitis B virus (HBV) RNA and hepatitis B core-related antigen (HBcrAg), as compared to conventional markers of HBV replication and disease activity, is unclear.

APPROACH AND RESULTS

Untreated participants in the North American Hepatitis B Research Network Adult Cohort Study were categorized by chronic hepatitis B (CHB) phases based on HBsAg and HBeAg status and HBV DNA and alanine aminotransferase (ALT) levels. HBV RNA and HBcrAg were measured (Abbott HBV pgRNA Research Assay and Fujirebio Lumipulse Immunoassay, respectively), and cross-sectional associations with conventional CHB markers were tested. Among 1,409 participants across all CHB phases, median HBV DNA was 3.8 log₁₀ IU/mL and ALT was 34 U/L. HBV RNA was quantifiable in 99% of HBeAg⁺ and 58% of HBeAg^- participants; HBcrAg was quantifiable in 20% of HBeAg⁺ (above linear range in the other 80%) and 51% of HBeAg^- participants. Both markers differed across CHB phases (P < 0.001), with higher levels in the HBeAg⁺ and HBeAg^- immune active phases. HBV RNA and HBcrAg correlated moderately strongly with HBV DNA in both HBeAg⁺ and HBeAg^- phases (HBV RNA: e⁺ ρ = 0.84; e^- ρ = 0.78; HBcrAg: e⁺ ρ = 0.66; e^- ρ = 0.56; P for all, <0.001), but with HBsAg levels among HBeAg⁺ phases only (HBV RNA: e⁺ ρ = 0.71; P < 0.001; e^- ρ = 0.18; P = 0.56; HBcrAg: e⁺ ρ = 0.51; P < 0.001; e^- ρ = 0.27; P < 0.001). Associations of higher HBV RNA and HBcrAg levels with higher ALT, APRI, and Fibrosis-4 levels were consistent in HBeAg^- , but not HBeAg⁺ , phases.

CONCLUSIONS

Despite clear relationships between HBV RNA and HBcrAg levels and CHB phases, these markers have limited additional value in differentiating CHB phases because of their strong association with HBV DNA and, to a lesser extent, with clinical disease indicators.

Hepatitis B Core-Related Antigen and New Therapies for Hepatitis B

The hepatitis B core-related antigen (HBcrAg) is an unprecedented novel HBV biomarker that plays an essential role in reflecting covalently closed circular DNA (cccDNA) in chronic hepatitis B (CHB) because its levels correlate with intrahepatic cccDNA and serum HBV DNA. In this review, we describe the clinical application of serum HBcrAg in CHB patients, with a particular focus on new therapies targeting intrahepatic HBV replication. (1) HBcrAg can be detected in clinical cases where serum HBV DNA is undetectable during anti-HBV therapy. (2) A highly sensitive HBcrAg assay (iTACT-HBcrAg) may be useful for monitoring HBV reactivation, as an alternative to HBV DNA. (3) Decreased HBcrAg levels have been significantly associated with promising outcomes in CHB patients, reducing the risk of progression or recurrence of hepatocellular carcinoma. Additionally, we focus on and discuss several drugs in development that target HBV replication, and monitoring HBcrAg may be useful for determining the therapeutic efficacies of such novel drugs. In conclusion, HBcrAg, especially when measured by the recently developed iTACT-HBcrAg assay, may be the most appropriate surrogate marker, over other HBV biomarkers, to predict disease progression and treatment response in CHB patients.

Hepatitis B core-related antigen predicts disease progression and hepatocellular carcinoma in hepatitis B e antigen-negative chronic hepatitis B patients

BACKGROUND AND AIM

The serum hepatitis B core-related antigen (HBcrAg) is considered a surrogate marker of the amount and activity of intrahepatic covalently closed circular DNA. This study aims to investigate the virological characteristics of HBcrAg in chronic hepatitis B (CHB) patients and to reveal the hepatocellular carcinoma (HCC) risk factors of hepatitis B e antigen (HBeAg)-negative patients.

METHODS

Hepatitis B core-related antigen was measured in 245 naive CHB patients before receiving nucleoside/nucleotide analog (NA) therapy. All patients were receiving NA (entecavir, tenofovir disoproxil fumarate, and tenofovir alafenamide) continuously for more than 1 year until the end of follow-up, and they did not have a history of HCC. Hepatitis B viral status was compared between 106 HBeAg-positive and 139 HBeAg-negative patients.

RESULTS

Median HBcrAg levels were significantly higher in HBeAg-positive patients than in HBeAg-negative patients (> 6.8 vs 3.7 log U/mL, P < 0.01). In HBeAg-negative patients, higher HBcrAg levels were associated with cirrhosis (119 chronic hepatitis/20 cirrhosis = 3.5/4.7 log U/mL, P = 0.03) and higher serum hepatitis B virus DNA. During a median follow-up of 5.28 (1.03-12.0) years, the 5-year cumulative HCC incidence rate was 5.4% in the HBeAg-negative cohort. In the multivariate Cox regression analysis, higher HBcrAg levels at 1 year were independent predictive factors for HCC development in HBeAg-negative patients who received NA therapy (cutoff value, 4.1 log U/mL; hazard ratio, 6.749; 95% confidence interval, 1.334-34.15, P < 0.01) and even in non-cirrhosis patients.

CONCLUSION

Hepatitis B core-related antigen was useful for understanding disease progression in CHB patients and for stratifying the risk for carcinogenesis in HBeAg-negative patients receiving NA therapy.

Ultrasensitive Assay for Hepatitis B Core-Related Antigen Predicts Hepatocellular Carcinoma Incidences During Entecavir

Serum hepatitis B core‐related antigen (HBcrAg) and surface antigen (HBsAg) are surrogate markers of intrahepatic covalently closed circular DNA. The measurement range of the current HBcrAg assay is relatively narrow. Thus, we examined the potential of HBcrAg and HBsAg measured by ultrasensitive assays for predicting hepatocellular carcinoma (HCC) development in patients with chronic hepatitis B treated with entecavir (ETV). We conducted a retrospective cohort study of 180 patients who received ETV for >1 year. All patients had hepatitis B e‐antigen negativity at baseline. Serum HBcrAg and HBsAg levels at baseline and year 1 were measured in all patients by ultrasensitive assays using immunoassay for total antigen including complex by pretreatment (iTACT) technology. During the median follow‐up of 11.0 years, 22 patients developed HCC (11.8/1,000 person‐years). Baseline HBsAg levels were not associated with HCC development during ETV treatment. However, high HBcrAg levels at baseline and at year 1 were significantly associated with HCC development (log‐rank test; P < 0.001). In 110 patients (61.1%) with ≥4.0 log U/mL at baseline (high HBcrAg cohort), HBcrAg declined to ≤2.9 log U/mL at year 1 in 25 patients (22.7%). The adjusted hazard ratio for HCC incidence was significantly lower in patients with HBcrAg ≤2.9 log U/mL at year 1 than in those in the high HBcrAg cohort. Conclusion: Measurement of HBcrAg by ultrasensitive assay has better potential for predicting HCC during antiviral treatment than the current HBcrAg assay.

The role of hepatitis B virus core-related antigen in predicting hepatitis B virus relapse after cessation of entecavir in hepatitis B e antigen-negative patients

This study investigated the ability of hepatitis B core-related antigen (HBcrAg) to predict hepatitis B virus (HBV) relapse in HBeAg-negative patients after cessation of entecavir therapy. A total of 301 HBeAg-negative patients without cirrhosis who had stopped entecavir therapy for at least 12 months were recruited. All patients fulfilled the stopping criteria proposed by the APASL 2012 guidelines. The five-year cumulative rates of virological relapse, clinical relapse and HBsAg loss were 71.6%, 57.3% and 18.7%, respectively. Serum HBsAg at end of treatment (EOT) was an independent predictor of virological relapse, clinical relapse and HBsAg loss; an EOT HBsAg of 150 IU/ml was the optimal cut-off value. The 5-year virological relapse rates for patients with <150 and ≥150 IU/ml HBsAg at EOT were 43.3% and 82.2% (p < 0.001), clinical relapse rates were 32.3% and 66.3% (p < 0.001), and HBsAg loss rates were 46.1% and 5.2% (p < 0.001), respectively. A baseline HBcrAg of 4 IU/ml was the optimal cut-off value for predicting HBV relapse. Among patients with an EOT HBsAg <150 IU/ml, the five-year virological relapse rates for patients with baseline HBcrAg levels ≤4 and >4 log U/ml were 27.9% and 59.1% (p = 0.006) and the clinical relapse rates were 18% and 48.1% (p = 0.014), respectively. EOT HBcrAg was not a significant predictor of virological or clinical relapse after cessation of entecavir. In conclusion, the combination of an EOT HBsAg of 150 IU/ml and baseline HBcrAg of 4 log U/ml can effectively predict the risk of HBV relapse after stopping entecavir therapy.

Clinical efficacy of a novel, high-sensitivity HBcrAg assay in the management of chronic hepatitis B and HBV reactivation

BACKGROUND & AIMS

A fully automated, novel high-sensitivity hepatitis B core-related antigen assay (iTACT-HBcrAg) has been developed. We demonstrate the clinical utility of iTACT-HBcrAg for monitoring chronic hepatitis B (CHB) and for the early detection of HBV reactivation.

METHODS

After fundamental assessments, the clinical performance of iTACT-HBcrAg was compared with other HBV markers. i) Serial sera, available from 161 HBeAg-negative patients with CHB and persistently undetectable HBV DNA, were measured by iTACT-HBcrAg and a conventional HBcrAg assay (G-HBcrAg). ii) Serial sera from 13 HBV-reactivated patients were measured by iTACT-HBcrAg and an ultra-high-sensitivity HBsAg immune complex transfer-chemiluminescent enzyme immunoassay (lower limit of detection; 0.0005 IU/ml, ICT-CLEIA) to compare HBV DNA detection. iii) To elucidate the various HBcrAg components detected by iTACT-HBcrAg, OptiPrep density gradient centrifugation analysis was performed on sera obtained before and after HBV reactivation.

RESULTS

The analytical performance of iTACT-HBcrAg was satisfactory. The sensitivity of iTACT-HBcrAg (2.1 Log U/ml) was approximately 10-fold greater than that of G-HBcrAg (2.8 Log U/ml). i) HBcrAg was detectable in the sera of 97.5% (157/161) of patients with CHB by iTACT-HBcrAg, of whom 75.2% (121/161) had ≥2.8 Log U/ml HBcrAg and 22.4% (36/161) had 2.1-2.8 Log U/ml HBcrAg, which was undetectable by G-HBcrAg. ii) 9 and 2 of 13 HBV-reactivated patients were HBcrAg-positive by iTACT-HBcrAg before and at HBV DNA positivity, respectively; 7 and 4 were HBcrAg-positive by iTACT-HBcrAg before and at HBsAg-positivity by ICT-CLEIA, respectively. iii) The HBcrAg detected by iTACT-HBcrAg before HBV reactivation was contained in empty particles (22 KDa precore protein).

CONCLUSIONS

iTACT-HBcrAg could be used to better monitor responses to anti-HBV treatments in HBeAg-negative patients and for the early detection of HBV reactivation.

LAY SUMMARY

A fully automated, novel high-sensitivity hepatitis B core-related antigen assay (iTACT-HBcrAg) has been developed. iTACT-HBcrAg can be used to monitor HBeAg-negative patients with chronic hepatitis B, as well as for the early detection of HBV reactivation. iTACT-HBcrAg could be used as a general marker of disease progression and treatment response.

Advances in treatment and prevention of hepatitis B

Chronic hepatitis B (CHB) continues to contribute to worldwide morbidity and mortality significantly. Scientists, clinicians, pharmaceutical companies, and health organizations have dedicated substantial Intellectual and monetary resources to finding a cure, increasing immunization rates, and reducing the global burden of CHB. National and international health-related organizations including the center for disease control, the national institute of health, the American Association for the study of liver disease (AASLD), The European association for the study of the Liver (EASL), The Asia Pacific association for the study of the Liver (APASL) and the world health organization release periodic recommendations for disease prevention and treatment. Our review of the most recent guidelines by EASL, AASLD, APASL, and Taiwan Association for the Study of the Liver revealed that an overwhelming majority of cited studies were published before 2018. We reviewed Hepatitis B-related literature published 2018 onwards to identify recent developments and current barriers that will likely direct future efforts towards eradicating hepatitis B. The breakthrough in our understanding of the hepatitis B virus life cycle and resulting drug development is encouraging with significant room for further progress. Data from high-risk populations, most vulnerable to the devastating effects of hepatitis B infection and reactivation remain sparse. Utilization of systems approach, optimization of experimental models, identification and validation of next-generation biomarkers, and precise modulation of the human immune response will be critical for future innovation. Within the foreseeable future, new treatments will likely complement conventional therapies rather than replace them. Most Importantly, pragmatic management of CHB related population health challenges must be prioritized to produce real-world results.

Quantitative serum HBV markers in predicting phases of natural history of chronic HBV infection

BACKGROUND

Clinical importance of commercially available quantitative HBV markers has not been fully investigated.

OBJECTIVE

To choice and to evaluate clinically valuable HBV markers for predicting phases of natural history with chronic HBV infection.

METHODS

472 naïve patients with chronic HBV infection were enrolled, in which 21 and 220 were confirmed as HBeAg-positive inactive and active hepatitis (EPIH and EPAH), respectively, and 106 and 125 were confirmed as HBeAg-negative inactive and active hepatitis (ENIH and ENAH), respectively. HBsAg, HBcrAg and anti- HBc were measured using chemiluminescent immunoassay, and HBV DNA was measured using PCR-fluorescence probing assay.

RESULTS

There were all statistical differences in medians of HBsAg, anti-HBc, HBcrAg and HBV DNA between EPIH and EPAH and between ENIH and ENAH (all P < 0.01). According to binary logistic stepwise regressions, HBsAg and anti-HBc were preferred variables for predicting EPAH, and HBcrAg and HBV DNA were preferred variables for predicting ENAH. Based on normalization for coefficients of preferred variables entering regression equations, a handy model of MEPAH for predicting EPAH and of MENAH for predicting ENAH was constructed, respectively. Area under receiver operating characteristic curves of MEPAH and MENAH for predicting EPAH and ENAH were 0.882 and 0.931, respectively. With standard of MEPAH ≤ 5.997 and MENAH > 10.535, sensitivity or specificity of which for predicting EPAH and ENAH were about 81.0 % and 87.0 %, respectively.

CONCLUSION

HBsAg and anti-HBc for predicting EPAH and HBcrAg and HBV DNA for predicting ENAH are dependable markers; MEPAH for predicting EPAH and MENAH for predicting ENAH have very good performance.

HBV RNA Profiles in Patients With Chronic Hepatitis B Under Different Disease Phases and Antiviral Therapy

BACKGROUND AND AIMS

Large-scale comprehensive studies on HBV RNA in chronic hepatitis B are lacking. We aimed to study the HBV RNA profile and its correlation with other viral markers in patients with chronic hepatitis B who are treatment-naïve and patients receiving nucleos(t)ide analogues (NA).

APPROACH AND RESULTS

Biomarkers, including HBV RNA and hepatitis B core-related antigen (HBcrAg), were measured in 388 patients. Of these, 246 were treatment-naïve and were categorized into HBeAg-positive chronic infection (n = 41), HBeAg-positive chronic hepatitis (n = 81), HBeAg-negative chronic infection (n = 39), HBeAg-negative chronic hepatitis (n = 66), and HBsAg seroclearance (n = 19). These biomarkers were also measured in 142 patients who were NA-treated receiving tenofovir or entecavir at baseline, week 48, and week 96. The pattern of serum HBV RNA levels mirrored HBV DNA (1-2 logs higher than HBV RNA) and HBcrAg in patients who were treatment-naïve. HBV RNA correlated best with HBcrAg (r = 0.84) and to a lesser extent with HBV DNA (r = 0.737) (both P < 0.001). In patients with HBsAg seroclearance, 15.8% and 15.8% had detectable serum HBV RNA and HBcrAg, respectively. NA treatment reduced serum HBV RNA by 1.46 logs and 1.77 logs at weeks 48 and 96, respectively. At week 96 of NA therapy, only 19.1% patients who were tenofovir-treated and 25.7% patients who were entecavir-treated had unquantifiable HBV RNA (P > 0.05). In patients who were treated and had undetectable HBV DNA, 77.5% and 30% had quantifiable HBV RNA and HBcrAg, respectively.

CONCLUSIONS

HBV RNA showed distinct and corresponding profiles in patients with HBV in different disease phases. HBV RNA and HBcrAg could be used to monitor residual transcriptional activities in patients with HBsAg seroclearance. NA led to reduction of serum HBV RNA. Monitoring of viral activities can still be achieved in patients with undetectable HBV DNA by serum HBV RNA.

Novel Biomarkers of Hepatitis B Virus and Their Use in Chronic Hepatitis B Patient Management

Even though an approved vaccine for hepatitis B virus (HBV) is available and widely used, over 257 million individuals worldwide are living with chronic hepatitis B (CHB) who require monitoring of treatment response, viral activity, and disease progression to reduce their risk of HBV-related liver disease. There is currently a lack of predictive markers to guide clinical management and to allow treatment cessation with reduced risk of viral reactivation. Novel HBV biomarkers are in development in an effort to improve the management of people living with CHB, to predict disease outcomes of CHB, and further understand the natural history of HBV. This review focuses on novel HBV biomarkers and their use in the clinical setting, including the description of and methodology for quantification of serum HBV RNA, hepatitis B core-related antigen (HBcrAg), quantitative hepatitis B surface antigen (qHBsAg), including ultrasensitive HBsAg detection, quantitative anti-hepatitis B core antigen (qAHBc), and detection of HBV nucleic acid-related antigen (HBV-NRAg). The utility of these biomarkers in treatment-naïve and treated CHB patients in several clinical situations is further discussed. Novel HBV biomarkers have been observed to provide critical clinical information and show promise for improving patient management and our understanding of the natural history of HBV.

Residual HBV DNA and pgRNA viraemia is associated with hepatocellular carcinoma in chronic hepatitis B patients on antiviral therapy

BACKGROUND

We aimed to assess whether residual hepatitis B virus (HBV) viraemia is associated with HCC development.

METHODS

This is a case-control study of 104 patients [52 HCC and 52 non-HCC (matched with age, gender, cirrhosis and treatment duration)] on ≥ 3 years entecavir (ETV) with unquantifiable HBV DNA by Cobas Taqman assay v2.0 (Roche Diagnostics; lower limit of quantification [LLOQ] 20 IU/mL). Serial sera within 1, 1-2, and > 2 years prior to HCC diagnosis or last follow-up (LFU) were measured for HBV DNA and pre-genomic (pg) RNA using a highly sensitive semi-quantitative PCR assay with lower limit of detection of 10 IU/mL and LLOQ of 51.5 IU/mL, respectively.

RESULTS

Among the 104 patients (80.8% male, median age 61.2 years old, 38.5% cirrhosis, median duration of ETV 45.5 months), 38.5% and 9.6% HCC patients had undetectable serum DNA and pgRNA, respectively, compared to 65.4% and 36.5% in non-HCC patients; P = 0.005 & 0.001, respectively, at the time of HCC diagnosis/LFU. Detectable HBV DNA and pgRNA were associated with a higher 2-year risk of HCC development (HR 2.79, 95% CI 1.424-5.468 & HR 4.544, 95% CI 1.07-19.289, respectively). No significant differences were observed for qHBsAg levels between HCC and non-HCC patients.

CONCLUSIONS

More than 50% CHB patients on ETV with HBV DNA < LLOQ by standard assay had persistent viraemia as determined by a more sensitive assay. Detectable HBV DNA or pgRNA by more sensitive assays was associated with HCC development. More potent viral suppression is required to further reduce the risk of HCC.