Impact of hepatitis B core-related antigen on the incidence of hepatocellular carcinoma in patients treated with nucleos(t)ide analogues

Differential HBV RNA and HBcrAg patterns in untreated patients with chronic hepatitis delta

BACKGROUND & AIMS

Serum HBV RNA and hepatitis B core-related antigen (HBcrAg) levels have been proposed as useful biomarkers in the management of patients with HBV; however, their role in chronic hepatitis delta (CHD) is currently unknown.

METHODS

Consecutive untreated patients with CHD were enrolled in a cross-sectional study in three EU centers. Clinical and virological characteristics were collected. Serum HBV RNA and HBcrAg levels were quantified by an automated real-time investigational assay (Cobas® 6800, Roche Diagnostics, Pleasanton, Ca, USA) and by LUMIPULSE® G HBcrAg assay (Fujirebio Europe), respectively. In 18 patients with available liver biopsies, intrahepatic analyses were performed.

RESULTS

Overall, 240 patients with HDV were enrolled: median age 46 years, 62% male, 53% with cirrhosis, 57% nucleos(t)ide analogue treated, median ALT 70 U/L, median HBsAg 3.8 log10 IU/ml, 88% HBeAg negative, and median HDV RNA 4.9 log10 IU/ml. HBV RNA was positive (>10 copies/ml) in only 8% of patients (median 40 [13-82,000] copies/ml), whereas HBcrAg was ≥3 log10 U/ml in 77% (median 4.2 [3.0-8.0] log10 U/ml). By combining these biomarkers, three categories were identified: 23% double negative (HBV RNA/HBcrAg), 9% double positive (HBV RNA/HBcrAg) and 68% HBV RNA negative/HBcrAg positive. HBV RNA levels positively correlated with male sex and detectable HBV DNA, while positive HBcrAg correlated with higher HBsAg levels. Double-positive patients were younger, non-European, with elevated ALT and HDV RNA levels and detectable HBV DNA. Intrahepatic HDV RNA and HBV RNA were positive in most samples, while intrahepatic levels of covalently closed circular DNA were low.

CONCLUSIONS

In untreated CHD, most patients had undetectable HBV RNA but quantifiable HBcrAg ("divergent pattern") in the absence of HBeAg. Additional studies aiming to unravel the molecular mechanisms underlying these findings are warranted.

IMPACT AND IMPLICATIONS

Serum HBV RNA and HBcrAg (hepatitis B core-related antigen) are promising biomarkers of the transcriptional activity of covalently closed circular DNA in chronic HBV infection; however, their role in patients with HBV-HDV coinfection is unknown. At variance with what is commonly observed in HBV-monoinfected patients, HBV RNA was undetectable and HBcrAg detectable in the serum of most patients with HDV ("divergent pattern"). The understanding of the viral interplay between HBV and HDV is crucial to dissect the pathogenic mechanisms associated with the distinct phenotypes of patients with HDV.

Hepatitis B core-related antigen as a predictive biomarker for recurrence in primary hepatocellular carcinoma: A meta-analysis

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the most common malignancies, with high recurrence rates after treatment. Identifying reliable biomarkers for predicting recurrence is essential for improving patient outcomes. Hepatitis B core-related antigen (HBcrAg) has shown potential as a predictive marker for HCC recurrence.

AIM

To evaluate the association between HBcrAg levels and the risk of HCC recurrence.

METHODS

A systematic review was conducted following PRISMA guidelines. PubMed, EMBASE, Web of Science, and the Cochrane Library were searched without restrictions on date or language. Observational studies reporting hazard ratios (HRs) for HBcrAg as a predictor of HCC recurrence were included. Data extraction and quality assessment were performed independently by two reviewers. Statistical analyses used a random-effects model to account for heterogeneity (I² ≥ 50%), and sensitivity analysis was performed to ensure the robustness of the results.

RESULTS

A total of 1339 articles were initially identified, and 17 studies were included in the final meta-analysis after screening. The pooled analysis showed a significant association between elevated HBcrAg levels and HCC recurrence (HR = 4.42, 95% confidence interval: 3.43-5.41) with substantial heterogeneity (I² = 92.6%). Subgroup analysis revealed higher pooled HRs in studies with ≥ 500 participants (HR = 4.18) and HBcrAg cut-offs ≥ 4.0 LogU/mL (HR = 5.29). Studies with ≥ 10 years of follow-up showed a lower HR (2.89) compared to those with < 10 years (3.27). Patients treated with nucleos(t)ide analogs had a pooled HR of 1.98, while those without nucleos(t)ide analog had a higher HR of 3.87. Sensitivity analysis confirmed the robustness of the results, with no significant publication bias detected.

CONCLUSION

This meta-analysis provides strong evidence that elevated HBcrAg levels are associated with an increased risk of HCC recurrence. HBcrAg may serve as a valuable biomarker for predicting recurrence, aiding personalized management and surveillance strategies for HCC patients.

Observational pilot study of switching from entecavir to tenofovir alafenamide in patients with chronic hepatitis B

This study evaluated the long-term efficacy and safety of the widely used drugs entecavir (ETV) and tenofovir alafenamide (TAF), as well as the incidence of HCC.A nonrandomized, prospective, observational analysis included 77 patients with chronic hepatitis B who were assigned to continue ETV or switch TAF. After 240 weeks, the mean changes in serum hepatitis B surface antigen (- 0.365 ± 0.069 log IU/mL vs. 0.301 ± 0.039 log IU/mL, p = 0.39) and hepatitis B core-related antigen (- 0.215 ± 0.092 log IU/mL vs. - 0.195 ± 0.056 log IU/mL) were not significantly different between the ETV and TAF groups. There were also no differences between the two groups in estimated glomerular filtration rate (- 5.407 ± 1.660 vs. - 2.666 ± 1.52, p = 0.240), urinary β2-microglobulin β/creatinine (ETV: 2.330 ± 0.374 at baseline and 2.335 ± 0.257 at 240 weeks; TAF: 2.720 ± 0.073 and 2.123 ± 0.310, p = 0.996 and 0.455, respectively) or urinary N-acetyl-β-D-glucosaminidase/creatinine (ETV: 0.040 ± 0.005 at baseline and 0.044 ± 0.004 at 240 weeks; TAF: 0.049 ± 0.005 and 0.053 ± 0.005, p = 0.642 and 0.684, respectively). Finally, no significant difference was found in the incidence of HCC between the ETV and TAF groups (log-rank test, p = 0.08). In conclusion, the long-term observation of this study demonstrated that ETV and TAF have comparable efficacy and safety.Clinical trial registration: UMIN000026465.

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.

Kinetics of the hepatitis B core-related antigen and treatment responses in chronic hepatitis B patients treated with tenofovir alafenamide

AIM

An association between hepatitis B core-related antigen (HBcrAg) kinetics and hepatocarcinogenesis during nucleoside (t)id analog (NA) treatment has recently been reported. HBcrAg kinetics and factors associated with HBcrAg response during tenofovir alafenamide (TAF) administration remain unclear. In this multicenter retrospective study, we aimed to clarify the efficacy and safety of TAF in treatment-naïve patients with chronic hepatitis B, focusing on the reduction in HBcrAg levels.

METHODS

Patients were treated with TAF monotherapy for 96 weeks, and the kinetics of HBcrAg during treatment and the factors associated with HBcrAg response (defined as a change in HBcrAg of -1 log IU/mL from baseline) were evaluated.

RESULTS

The study population comprised 241 patients, 36.9% of whom were HBeAg-positive. The median baseline HBcrAg level was 4.7 log IU/mL. The median change in HBcrAg from baseline was -1.1 log IU/mL at 96 weeks after treatment. The HBcrAg response rate at 96 weeks was 56.6% (43/76). Multivariate analysis revealed high alanine transaminase level as an independent baseline factor associated with HBcrAg response at 96 weeks of treatment (p = 4.53 × 10-6). No correlation was found between the HBcrAg and hepatitis B surface antigen kinetics in patients treated with TAF monotherapy.

CONCLUSIONS

In TAF monotherapy for patients with chronic hepatitis B, HBcrAg levels were significantly decreased and baseline alanine transaminase level is an important factor associated with HBcrAg reduction. As no correlation was found between HBcrAg and reduced hepatitis B surface antigen levels in this study, HBcrAg kinetics in addition to hepatitis B surface antigen may need to be monitored during TAF treatment.

High serum growth differentiation factor 15 is a risk factor for the occurrence of hepatocellular carcinoma in chronic hepatitis B patients treated with nucleos(t)ide analogs

AIM

Patients with chronic hepatitis B (CHB) remain at risk for hepatocellular carcinoma (HCC) even with nucleos(t)ide analog therapy. We evaluated risk factors for HCC development, including serum hepatitis B virus (HBV) RNA, hepatitis B core-related antigen level, and growth differentiation factor 15 (GDF15) level, a predictor of HCC development in patients with chronic hepatitis C.

METHODS

We collected clinical data and stored serum from CHB patients without a history of HCC who were receiving nucleos(t)ide analog treatment for more than 1 year and whose HBV DNA level was less than 3.0 log IU/mL. We measured the serum levels of HBV RNA and GDF15.

RESULTS

Among 242 CHB patients, 57 had detectable HBV RNA, and GDF15 was quantified in all patients. The median GDF15 level was 0.86 ng/mL. Cox proportional hazards analysis revealed that male sex and higher GDF15, FIB-4 index, alpha-fetoprotein and gamma-glutamyl transpeptidase were independent risk factors for HCC. The presence of HBV RNA above the lower limit of quantification was not a risk factor. When we set cutoff values based on the Youden index, the cumulative incidence of HCC was significantly higher in the male, AFP ≥3.0 ng/mL, gamma-glutamyl transpeptidase ≥22 U/L, FIB-4 index ≥1.93, and GDF-15 ≥1.17 ng/mL groups. In patients with no or more than three of these five risk factors, the 10-year HCC cumulative incidence rates were 0% and 41.0%, respectively.

CONCLUSIONS

High serum GDF15 is an independent risk factor for the occurrence of HCC in CHB patients treated with nucleos(t)ide analogs.

Role of hepatitis B core-related antigen in predicting the occurrence and recurrence of hepatocellular carcinoma in patients with chronic hepatitis B: A systemic review and meta-analysis

BACKGROUND AND AIM

The purpose of the current study was to investigate the predictive value of hepatitis B core-related antigen (HBcrAg) on the occurrence and recurrence of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B (CHB).

METHODS

We searched PubMed, Embase, Scopus, and Web of Science from database inception to April 6, 2023. Pooled hazard ratio (HR) or odds ratio (OR) with 95% confidence interval (CI) was calculated for the occurrence and recurrence of HCC.

RESULTS

Of the 464 articles considered, 18 articles recruiting 10 320 patients were included. The pooled results showed that high serum HBcrAg level was an independent risk factor for the occurrence of HCC in CHB patients (adjusted HR = 3.12, 95% CI: 2.40-4.06, P < 0.001, I2 = 43.2%, P = 0.043; OR = 5.65, 95% CI: 3.44-5.82, P < 0.001, I2 = 0.00%, P = 0.42). Further subgroup analysis demonstrated that the predictive ability of HBcrAg for the occurrence of HCC is not influenced by the hepatitis B e antigen (HBeAg) status or the use of nucleoside/nucleotide analogs (NAs). In addition, our meta-analysis also suggests that HBcrAg is a predictor of HCC recurrence (adjusted HR = 1.71, 95% CI: 1.26-2.32, P < 0.001, I2 = 7.89%, P = 0.031).

CONCLUSIONS

For patients with CHB, serum HBcrAg may be a potential predictive factor for the occurrence of HCC, regardless of HBeAg status or NA treatment. It may also serve as a novel prognostic biomarker for the recurrence of HCC. More studies are needed to confirm our conclusions.

Newer Diagnostic Virological Markers for Hepatitis B Virus Infection

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

How to cite this article

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

Clinical performance of Circulating HBV RNA and iTACT-HBcrAg Assays in HBeAg-negative and HBsAg-cleared Chronic Hepatitis B Patients

Hepatitis B virus (HBV) RNA and hepatitis B core-related antigen (HBcrAg) have been reported to reflect the transcriptional activity of covalently closed circular HBV DNA. We retrospectively investigated the proportions of quantifiable serum HBV RNA and immunoassay for total antigen including complex via pretreatment-hepatitis B core-related antigen (iTACT-HBcrAg) in chronic hepatitis B patients negative for hepatitis B e antigen (HBeAg) and/or with hepatitis B surface antigen (HBsAg) seroclearance. This study included 246 HBeAg-negative HBV-infected patients, who comprised 13 with liver cirrhosis (LC, the LC group), 118 chronic hepatitis (CH, the CH group), and 115 inactive carriers (IC, the IC group), and 44 patients with HBsAg seroclearance. iTACT-HBcrAg and HBV RNA levels were determined using stored serum samples. Higher proportions of the patients had quantifiable iTACT-HBcrAg than HBV RNA in all groups of HBeAg-negative patients (iTACT-HBcrAg: 84.6%, 90.7%, 35.7%, HBV RNA: 23.1%, 26.3%, 14.8%, for the LC, CH, IC groups). With HBsAg seroclearance (HBsAg <0.05 IU/mL), the proportions of quantifiable samples for HBV RNA were also lower than iTACT-HBcrAg (0% for HBV RNA). Thus, iTACT-HBcrAg was more often detectable than circulating HBV RNA in this study population. Further long-term prospective evaluation of iTACT-HBcrAg is desirable for its utilization in clinical practice.

Latest insights into the epidemiology, characteristics, and therapeutic strategies of chronic hepatitis B patients in indeterminate phase

As a hepatotropic virus, hepatitis B virus (HBV) can establish a persistent chronic infection in the liver, termed, chronic hepatitis B (CHB), which causes a series of liver-related complications, including fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). HCC with HBV infection has a significantly increased morbidity and mortality, whereas it could be preventable. The current goal of antiviral therapy for HBV infection is to decrease CHB-related morbidity and mortality, and achieve sustained suppression of virus replication, which is known as a functional or immunological cure. The natural history of chronic HBV infection includes four immune phases: the immune-tolerant phase, immune-active phase, inactive phase, and reactivation phase. However, many CHB patients do not fit into any of these defined phases and are regarded as indeterminate. A large proportion of indeterminate patients are only treated with dynamic monitoring rather than recommended antiviral therapy, mainly due to the lack of definite guidelines. However, many of these patients may gradually have significant liver histopathological changes during disease progression. Recent studies have focused on the prevalence, progression, and carcinogenicity of indeterminate CHB, and more attention has been given to the prevention, detection, and treatment for these patients. Herein, we discuss the latest understanding of the epidemiology, clinical characteristics, and therapeutic strategies of indeterminate CHB, to provide avenues for the management of these patients.

Two Concepts of Hepatitis B Core-Related Antigen Assay: A Highly Sensitive and Rapid Assay or an Effective Tool for Widespread Screening

Hepatitis B core-related antigen (HBcrAg) reflects the activity of intrahepatic covalently closed circular DNA. HBcrAg can be detected even in chronic hepatitis B patients in whom serum HBV DNA or hepatitis B surface antigen is undetectable. The HBcrAg measurement system was developed based on two concepts. One is a fully-automated and highly-sensitive HBcrAg assay (iTACT-HBcrAg) and the other is a point-of-care testing (POCT) that can be used in in resource-limited areas. iTACT-HBcrAg is an alternative to HBV DNA for monitoring HBV reactivation and predicting the development of hepatocellular carcinoma. This validated biomarker is available in routine clinical practice in Japan. Currently, international guidelines for the prevention of mother-to-child transmission recommend anti-HBV prophylaxis for pregnant women with high viral loads. However, over 95% of HBV-infected individuals live in countries where HBV DNA quantification is widely unavailable. Given this situation, a rapid and simple HBcrAg assay for POCT would be highly effective. Long-term anti-HBV therapy may have potential side effects and appropriate treatment should be provided to eligible patients. Therefore, a simple method of determining the indication for anti-HBV treatment would be ideal. This review provides up-to-date information regarding the clinical value of HBcrAg in HBV management, based on iTACT-HBcrAg or POCT.

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.

Clinical outcome after cessation of nucleos(t)ide analog treatment in chronic hepatitis B patients who achieved HBsAg seroclearance

BACKGROUND

We determined the long-term clinical outcome and the durability of treatment cessation after HBsAg seroclearance following nucleos(t)ide analog (NA) therapy in patients with chronic hepatitis B (CHB).

METHODS

We analyzed virological relapse (VR), HBsAg reversion, clinical relapse, and changes in HBsAg and HBcrAg levels by iTACT assay after treatment cessation of 90 CHB patients who achieved HBsAg seroclearance by NA treatment.

RESULTS

Median age of patients at treatment cessation was 57 years. Median duration of NA treatment and follow-up from cessation of NA were 9.25 and 5.2 years, respectively. Although VR occurred in 19 of 90 (21.1%) patients, HBV DNA levels of 18 patients had temporal elevations and sustained levels under the detection level thereafter. HBsAg reversion using Architect HBsAg QT assay occurred in six patients (6.7%) after cessation of NA. Five patients had temporal HBsAg level elevations and sustained levels under the detection level thereafter. One patient had virological and clinical relapse at 6 months after cessation of NA, and received NA re-treatment. HBsAg levels by iTACT assay from end of treatment (EOT) gradually decreased and in 18 of 28 (64%) patients reached an undetectable level at 5 years after EOT. In contrast, HBcrAg levels by iTACT assay slowly decreased, and in 8 of 29 patients (28%) reached an undetectable level at 5 years after EOT.

CONCLUSIONS

Patients receiving NA treatment who achieved HBsAg seroclearance as determined by HBsAg QT assay rarely experienced virological or clinical relapse after the cessation of treatment.

Kinetics of HBcrAg and HBsAg using highly sensitive iTACT assays in chronic hepatitis B patients with HBsAg seroclearance

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

High-risk population of progressive hepatic fibrosis in chronic hepatitis B patients on antiviral therapy

BACKGROUND

Progressive hepatic fibrosis leads to hepatocellular carcinoma (HCC) and decompensated cirrhosis. The aim of this study was to identify the high-risk population for progressive hepatic fibrosis and the incidence of HCC and decompensated cirrhosis in chronic hepatitis B (CHB) patients with antiviral therapy.

METHODS

The data came from a multicenter, center-randomized, double-blind clinical trial that analyzed only patients in the ETV-treated arm. There was 156 hepatitis B e antigen (HBeAg)-positive and 135 HBeAg-negative patients in 14 institutions. The primary endpoint was fibrosis reversal on 72-week Entecavir (ETV) treatment. The 7-year cumulative incidence of HCC and decompensated cirrhosis were analyzed. Multivariate logistic and LASSO regression analyses were used to screen variables associated with fibrosis reversal.

RESULTS

86/156 (55%) HBeAg-positive and 58/135 (43%) HBeAg-negative patients achieved fibrosis reversal on 72-week ETV treatment. Average age was 43 years, 203 (69.8%) was male, and 144 (49.5%) patients had cirrhosis. Age ≥ 40 years (OR: 0.46, 95% CI 0.23-0.93) and HBcrAg ≥ 8.23 log U/ml (OR: 2.72, 95% CI 1.33-5.54) in HBeAg-positive patients and HBV genotype C (OR: 0.44, 95% CI 0.21-0.97) in HBeAg-negative patients were independent factors of fibrosis reversal. It was confirmed in patients with cirrhosis. After 7-year ETV treatment, seven (4.5%) HBeAg-positive patients occurred HCC or decompensated cirrhosis, including four patients with age ≥ 40 years and six with HBcrAg 8.23log U/ml, while twelve (8.9%) HBeAg-negative patients occurred, including eleven with HBV genotype C.

CONCLUSIONS

HBeAg-positive patients with a low HBcrAg level or old age, and HBeAg-negative patients with HBV genotype C tended to develop progressive hepatic fibrosis and had a high incidence of HCC and decompensated cirrhosis, even on ETV treatment.

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.

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.

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.

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.

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.

Recurrent hepatocellular carcinoma with osteoclast-like giant cells: a case report

Background

Hepatocellular carcinoma with osteoclast-like giant cells is very rare and has an extremely poor prognosis. Here, we report a case of hepatocellular carcinoma with osteoclast-like giant cells that had a relatively better prognosis.

Case presentation

A 70-year-old Japanese man with hepatitis B virus-related liver cirrhosis was admitted to our hospital for the treatment of recurrent hepatocellular carcinoma. At the age of 60 years, he was first diagnosed as having hepatocellular carcinoma in the right lobe (9 cm in diameter), and liver resection of segment 7/8 was performed. Histological findings showed well-differentiated hepatocellular carcinoma. Since then, imaging studies have been performed every 3 or 4 months. One year later, hepatocellular carcinoma recurred in the lateral segment, and radiofrequency ablation was performed. Nine years after the first presentation, hepatocellular carcinoma recurrences were detected in the caudate lobe and segment 5 by imaging studies. Surgical resection of the caudate lobe was performed, and ultrasonography-guided radiofrequency ablation was subsequently performed for the segment 5 tumor. The resected tumor was simple nodular, well-differentiated HCC; it measured 21 × 21 mm and contained many osteoclast-like giant cells. As neither vascular nor bile duct invasion was found, we believe that radical resection was achieved. Since then, the hepatocellular carcinoma has not recurred for over a year and a half.

Conclusion

Hepatocellular carcinoma with osteoclast-like giant cells is very rare and the prognosis is extremely poor, but early detection can lead to a better clinical course.

Episodic Detectable Viremia Does Not Affect Prognosis in Untreated Compensated Cirrhosis With Serum Hepatitis B Virus DNA <2,000 IU/mL

INTRODUCTION

The necessity of antiviral therapy (AVT) for hepatitis B virus (HBV)-infected compensated cirrhosis with low-level viremia (LLV) is controversial. Herein, we evaluated its natural history.

METHODS

From 3 tertiary hospitals, we enrolled untreated patients with compensated cirrhosis with persistent serum HBV-DNA levels <2,000 IU/mL; LLV was defined as having at least 1 detectable serum HBV-DNA (20-2,000 IU/mL) episode, whereas maintained virological response (MVR) was defined as having persistently undetectable serum HBV-DNA (<20 IU/mL). When serum HBV-DNA was ≥2,000 IU/mL during follow-up, AVT was administered according to guidelines. Study end points were development of cirrhotic complication event (CCE) or hepatocellular carcinoma (HCC).

RESULTS

Among 567 patients analyzed, cumulative HCC risk at 3, 5, and 7 years was comparable between LLV (n = 391) vs MVR (n = 176) groups (5.7%, 10.7%, and 17.3% vs 7.2%, 15.5%, and 19.4%, respectively [P = 0.390]). CCE risk was also comparable between 2 groups (7.5%, 12.8%, and 13.7% vs 7.8%, 12.3%, and 14.6%, respectively [P = 0.880]). By multivariate analysis, LLV (vs MVR) was not associated with HCC or CCE risks, with adjusted hazard ratios of 1.422 (95% confidence interval [CI] 0.694-2.913; P = 0.336) and 1.816 (95% CI: 0.843-3.911; P = 0.128), respectively. Inverse probability of treatment weighting analysis yielded comparable outcomes between 2 groups, regarding HCC and CCE risks with hazard ratios of 0.903 (95% CI: 0.528-1.546; P = 0.711) and 1.192 (95% CI: 0.675-2.105; P = 0.545), respectively.

DISCUSSION

Episodic LLV among untreated patients with compensated cirrhosis does not increase the risk of disease progression compared with MVR status. Thus, the benefits of AVT for episodic LLV should be re-evaluated.

Soluble programmed cell death-1 predicts hepatocellular carcinoma development during nucleoside analogue treatment

Soluble immune checkpoint molecules are emerging novel mediators of immune regulation. However, it is unclear whether soluble immune checkpoint proteins affect the development of hepatocellular carcinoma (HCC) during nucleos(t)ide analogue (NA) treatment in patients with chronic hepatitis B virus infection. This study included 122 NA-naïve patients who received NA therapy. We assessed the associations of clinical factors, including soluble immune checkpoint proteins, with HCC development during NA treatment. The baseline serum concentrations of 16 soluble immune checkpoint proteins were measured using multiplexed fluorescent bead-based immunoassay. In total, 13 patients developed HCC during the follow-up period (median duration, 4.3 years). Of the 16 proteins, soluble inducible T-cell co-stimulator (≥ 164.71 pg/mL; p = 0.014), soluble programmed cell death-1 (sPD-1) (≤ 447.27 pg/mL; p = 0.031), soluble CD40 (≤ 493.68 pg/mL; p = 0.032), and soluble herpes virus entry mediator (≤ 2470.83 pg/mL; p = 0.038) were significantly associated with HCC development (log-rank test). In multivariate analysis, an sPD-1 level ≤ 447.27 pg/mL (p = 0.014; hazard ratio [HR], 4.537) and α-fetoprotein level ≥ 6.4 ng/mL (p = 0.040; HR, 5.524) were independently and significantly associated with HCC development. Pre-treatment sPD-1 is a novel predictive biomarker for HCC development during NA treatment.

Development of hepatocellular carcinoma from various phases of chronic hepatitis B virus infection

BACKGROUND & AIMS

There is insufficient data on the clinical course of chronic hepatitis B (CHB) patients in the immune-tolerant (IT) and immune-clearance, inactive (IC) phases over a long follow-up period.

DESIGN

We enrolled 466 CHB patients from our historical cohort, including 56 IT+MA　 (mildly active), 134 IC, 230 with chronic active hepatitis (CH) and 46 with liver cirrhosis (LC), who were categorized to each phase by at least one year of follow-up period from the first visit to our hospital. We investigated long-term risks, and their factors, of developing hepatocellular carcinoma (HCC), and the transition between the clinical phases, especially in the IT+MA and IC groups.

RESULTS

Of the 56 patients in the IT+MA group, 27 remained the IT+MA phase, but 29 transitioned to the CH phase and started nucleot(s)ide analogue (NA) treatment during the follow-up period. Meanwhile, of the 134 patients in the IC group, only 5 started NA treatment after progressing to the CH phase. The development of HCC from the IT+MA, IC, CH, and LC groups was observed in 2, 2, 9, and 20 cases, respectively. The cumulative incidence rates of developing HCC in the IT+MA, IC, CH, and LC groups were 9.9, 1.8, 3.0, and 53.1% at 10 years. In the CH and LC group, patients who developed HCC were older, had higher levels of FIB-4 index, M2BPGi, HBcrAg and AFP, and had lower levels of albumin and platelet counts. In CH patients, FIB-4 index levels were elevated at the diagnosis of HCC compared to baseline, whereas these decreased during the follow-up period in non-HCC patients.

CONCLUSIONS

HCC occurred at a certain rate among patients in the IT+MA and IC groups. Careful follow-up is required for CH patients with higher levels of FIB-4 index and/or M2BPGi because of the high incidence of HCC development. (299 words).

The association between hepatocarcinogenesis and intracellular alterations due to hepatitis B virus infection

Chronic hepatitis B virus (HBV) infection is a worldwide health problem leading to severe liver dysfunction, including liver cirrhosis and hepatocellular carcinoma. Although current antiviral therapies for chronic HBV infection have been improved and can lead to a strong suppression of viral replication, it is difficult to completely eliminate the virus with these therapies once chronic HBV infection is established in the host. Furthermore, chronic HBV infection alters intracellular metabolism and signalling pathways, resulting in the activation of carcinogenesis in the liver. HBV produces four viral proteins: hepatitis B surface-, hepatitis B core-, hepatitis B x protein, and polymerase; each plays an important role in HBV replication and the intracellular signalling pathways associated with hepatocarcinogenesis. In vitro and in vivo experimental models for analyzing HBV infection and replication have been established, and gene expression analyses using microarrays or next-generation sequencing have also been developed. Thus, it is possible to clarify the molecular mechanisms for intracellular alterations, such as endoplasmic reticulum stress, oxidative stress, and epigenetic modifications. In this review, the impact of HBV viral proteins and intracellular alterations in HBV-associated hepatocarcinogenesis are discussed.

Blood-Based Biomarkers in Hepatitis B Virus-Related Hepatocellular Carcinoma, Including the Viral Genome and Glycosylated Proteins

Hepatitis B virus (HBV) infection is a major risk factor for hepatocellular carcinoma (HCC) development and is a global public health issue. High performance biomarkers can aid the early detection of HCC development in HBV-infected individuals. In addition, advances in the understanding of the pathogenesis of HBV infection and in clinical laboratory techniques have enabled the establishment of disease-specific tests, prediction of the progression of liver diseases, including HCC, and auxiliary diagnosis of HCC, using blood-based methods instead of biopsies of liver or HCC tissues. Viral factors such as the HBV genotype, HBV genetic mutations, HBV DNA, and HBV-related antigens, as well as host factors, such as tumor-associated proteins and post-translational modifications, especially glycosylated proteins, can be blood-based, disease-specific biomarkers for HCC development in HBV-infected patients. In this review, we describe the clinical applications of viral biomarkers, including the HBV genome and glycosylated proteins, for patients at a risk of HBV-related HCC, based on their molecular mechanisms. In addition, we introduce promising biomarker candidates for practical use, including colony stimulating factor 1 receptor (CSF1R), extracellular vesicles, and cell-free, circulating tumor DNA. The clinical use of such surrogate markers may lead to a better understanding of the risk of disease progression and early detection of HCC in HBV-infected patients, thereby improving their prognosis.

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.

Entecavir Reduced Serum Hepatitis B Core-Related Antigen in Chronic Hepatitis B Patients with Hepatocellular Carcinoma

Serum hepatitis B core-related antigen (HBcrAg) was shown to predict the risk of hepatocellular carcinoma (HCC) in chronic hepatitis B (CHB) patients undergoing treatment. We investigated the longitudinal profile of HBcrAg in entecavir (ETV)-treated CHB patients with subsequent HCC development. We identified HCC cases diagnosed at ≥1 year after ETV initiation. CHB patients without HCC (matched for age, sex, cirrhosis status, baseline hepatitis B virus [HBV] DNA level, and ETV treatment duration) were identified as controls at an HCC:non-HCC ratio of 1:2. Serum samples were retrieved at baseline (ETV initiation) and at 3 and 5 years of ETV therapy for HBcrAg measurement (log IU/mL). In total, 180 patients (60 HCC patients matched with 120 CHB patients without HCC; median age, 56.5 years; 80.6% male; baseline HBV DNA, 5.9 log IU/mL; median follow-up, 6.8 years) were recruited. The median time from ETV initiation to HCC development was 3.2 years. HBcrAg levels were higher in HCC cases than in controls at all three time points: 5.69 log IU/mL versus 5.02 log IU/mL (p=0.025), 4.23 log IU/mL versus 3.36 log IU/mL (p=0.007), and 3.86 log IU/mL versus 3.36 log IU/mL (p=0.009), respectively. ETV led to similar rates of decline in HBcrAg from baseline to 3 years in both groups (0.34 log IU/mL/year vs 0.39 log IU/mL/year, p=0.774), although the decline from 3 to 5 years was slower in the non-HCC group (0.05 log IU/mL/year) than in the HCC group (0.09 log IU/mL/year, p=0.055). ETV time-dependently reduced HBcrAg in HCC and non-HCC patients. HBcrAg interpretation should consider the antiviral treatment duration.

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.

Screening for Hepatocellular Carcinoma in Chronic Hepatitis B: An Update

(1) Background: Hepatocellular carcinoma (HCC) is an important cause of mortality in individuals with chronic hepatitis B infection, with screening of high-risk groups recommended in all major international guidelines. Our understanding of the risk factors involved has improved over time, encouraging researchers to develop models that predict future risk of HCC development. (2) Methods: A literature search of the PubMed database was carried out to identify studies that derive or validate models predicting HCC development in patients with chronic hepatitis B. Subsequently, a second literature search was carried out to explore the potential role of novel viral biomarkers in this field. (3) Results: To date, a total of 23 models have been developed predicting future HCC risk, of which 12 have been derived from cohorts of treatment-naïve individuals. Most models have been developed in Asian populations (n = 20), with a smaller number in Caucasian cohorts (n = 3). All of the models demonstrate satisfactory performance in their original derivation cohorts, but many lack external validation. In recent studies, novel viral biomarkers have demonstrated utility in predicting HCC risk in patients with chronic hepatitis B, amongst both treated and treatment-naïve patients. (4) Conclusion: Several models have been developed to predict the risk of HCC development in individuals with chronic hepatitis B infection, but many have not been externally validated outside of the Asian population. Further research is needed to refine these models and facilitate a more tailored HCC surveillance programme in the future.

Viral Biomarkers for Hepatitis B Virus-Related Hepatocellular Carcinoma Occurrence and Recurrence

Hepatocellular carcinoma (HCC) is the sixth most common cancer worldwide and the fourth leading cause of cancer-related death. The most common risk factor for developing HCC is chronic infection with hepatitis B virus (HBV). Early stages of HBV-related HCC (HBV-HCC) are generally asymptomatic. Moreover, while serum alpha-fetoprotein (AFP) and abdominal ultrasound are widely used to screen for HCC, they have poor sensitivity. Thus, HBV-HCC is frequently diagnosed at an advanced stage, in which there are limited treatment options and high mortality rates. Serum biomarkers with high sensitivity and specificity are crucial for earlier diagnosis of HCC and improving survival rates. As viral-host interactions are key determinants of pathogenesis, viral biomarkers may add greater diagnostic power for HCC than host biomarkers alone. In this review, we summarize recent research on using virus-derived biomarkers for predicting HCC occurrence and recurrence; including circulating viral DNA, RNA transcripts, and viral proteins. Combining these viral biomarkers with AFP and abdominal ultrasound could improve sensitivity and specificity of early diagnosis, increasing the survival of patients with HBV-HCC. In the future, as the mechanisms that drive HBV-HCC to become clearer, new biomarkers may be identified which can further improve early diagnosis of HBV-HCC.

Clinical Implications of Serum Hepatitis B Virus Pregenomic RNA Kinetics in Chronic Hepatitis B Patients Receiving Antiviral Treatment and Those Achieving HBsAg Loss

Serum hepatitis B virus (HBV) pregenomic RNA (pgRNA) is correlated with covalently closed circular DNA. We aimed to investigate the utility of serum HBV pgRNA in chronic hepatitis B patients receiving nucleos(t)ide analogue treatment and those achieving HBsAg loss. One hundred and eighty-five patients were enrolled for studying long-term HBV pgRNA kinetics during treatment. Twenty patients achieving HBsAg loss after treatment were enrolled for examining HBV pgRNA kinetics around HBsAg loss. HBV pgRNA significantly decreased in the high baseline HBV pgRNA (≥6 log copies/mL) group but significantly increased in the low baseline HBV pgRNA (<4 log copies/mL) group after 3-month entecavir treatment. Among the 20 patients achieving HBsAg loss, 13 (65%) patients had serum HBV pgRNA higher than the limit of detection (LOD, 1466 copies/mL) when they achieved HBsAg loss. Finally, all 20 patients had HBV pgRNA going below the LOD within 3 years after achieving HBsAg loss. In conclusion, baseline serum HBV pgRNA alone is insufficient for predicting the trajectory of HBV pgRNA. Most patients still had HBV pgRNA higher than the LOD when they achieved HBsAg loss. Further studies on HBV pgRNA kinetics around HBsAg loss would provide an enhanced basis for further applications of HBV pgRNA.

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.

Hepatitis B Core-Related Antigen: From Virology to Clinical Application

Hepatitis B core-related antigen (HBcrAg) is a composite measure of the serum levels of hepatitis B e antigen, hepatitis B core antigen, and a 22-kDa precore protein. It has been shown to reflect the level and transcriptional activity of covalently closed circular DNA in the liver. Longitudinal cohort studies have improved our understanding of the role of this novel viral marker in the natural history of chronic hepatitis B. HBcrAg kinetics reflect the response to peginterferon, and its role in defining guidelines for stopping peginterferon therapy has been evaluated. HBcrAg is a marker of intrahepatic viral activity, which may influence the risk of hepatocellular carcinoma. In this article, we review the virology and role of HBcrAg in defining phases of chronic hepatitis B. Furthermore, the function of HBcrAg in predicting treatment outcomes and its role in monitoring response to novel antiviral agents will be discussed.

Potential of ultra-highly sensitive immunoassays for hepatitis B surface and core-related antigens in patients with or without development of hepatocellular carcinoma after hepatitis B surface antigen seroclearance

AIMS

Hepatitis B surface antigen (HBsAg) seroclearance indicates a "functional cure" in chronic hepatitis B (CHB) virus infection. However, several cases of hepatocellular carcinoma (HCC) development have been reported after HBsAg seroclearance. We evaluated the potential of HBsAg and hepatitis B core-related antigen (HBcrAg), measured by the ultra-highly sensitive assays, in cases with HCC development after HBsAg seroclearance.

METHODS

We enrolled 17 patients with CHB who achieved HBsAg seroclearance, defined by the conventional assay using Architect HBsAg QT kit (five HCC patients and 12 non-HCC patients). HBsAg and HBcrAg were measured in their stored serum samples using ultra-highly sensitive assays featuring "immunoassay for total antigen including complex via pretreatment (iTACT)" technology.

RESULTS

All five patients who developed HCC were positive for HBsAg or HBcrAg by iTACT-HBsAg or iTACT-HBcrAg at all follow-up points. HBcrAg levels in the HCC group, using iTACT-HBcrAg, were significantly higher than those in the non-HCC group at HBsAg seroclearance (3.6 LogU/ml (2.8-4.2) versus 2.6 (<2.1-3.8), p = 0.020). The best cutoff value of iTACT-HBcrAg for predicting HCC development was 2.7 LogU/ml by receiver operating characteristic curve analysis. The prevalence of HBcrAg ≥2.7 in the HCC group was significantly higher than that in non-HCC group (100% [5/5] versus 33% [4/12], p = 0.029).

CONCLUSIONS

Residual low viral antigen might predict HCC development even if HBsAg seroclearance was achieved according to a conventional assay. The results suggest that iTACT assays of HBsAg and HBcrAg would be useful for monitoring CHB patients.

Three Heads are Better than Two: HBcrAg as a New Predictor of HBV-related HCC

Patients with chronic hepatitis B virus (HBV) infection are at risk of developing hepatocellular carcinoma (HCC), and serum markers reflecting viral replication are potential predictors for HCC development. Besides the levels of serum HBV DNA and hepatitis B surface antigen (HBsAg), hepatitis B core-related antigen (HBcrAg) quantification is an emerging serological marker for viral replication. Unlike HBV DNA and HBsAg, HBcrAg is a covalently closed circular DNA-derived protein marker, consisting of hepatitis B e antigen (HBeAg), p22cr, and hepatitis B core antigen. In treatment-naïve HBV patients, higher HBcrAg levels are shown to be associated with an increased risk of HCC in several studies. More importantly, HBcrAg may complement HBV DNA level to predict HCC development. For example, an Asian treatment-naïve cohort study’s data showed that HBcrAg level of 4 log U/mL was effective to stratify HCC risk in HBeAg-negative patients with intermediate viral loads, who may not need antiviral therapy because of the low to moderate risk of HCC. In patients receiving prolonged nucleos(t)ide analogue with profound viral suppression, most data indicated that HBV DNA and HBsAg levels no longer serve as HCC predictors. However, several studies suggested on-treatment HBcrAg levels may remain as an HCC predictor. In summary, HBcrAg level can be a useful biomarker for treatment-naïve patients, but its value in on-treatment patients needs validation. The next challenge is how to combine HBcrAg with the other viral markers to construct a better HCC prediction model, optimizing the management of HBV patients.

Hepatitis B virus-related hepatocellular carcinoma in the era of antiviral therapy: The emerging role of non-viral risk factors

Hepatocellular carcinoma (HCC), one of the major malignant lethal tumours, is most prevalent in Asian patients with chronic hepatitis B virus (HBV) infection. Both viral and non-viral factors contribute to the development of HCC. It is established that viral factors associated with HBV DNA level, HBV genotype, designated gene mutation, HBV DNA integration, HBx protein, hepatitis B surface antigen (HBsAg), hepatitis B core-related antigen (HBcrAg) and HBV RNA are correlated with hepatocarcinogenesis. Before the introduction of antiviral therapy, viral factors once attracted more attention during the development of HCC. With the widespread use of antiviral therapy, predominantly nucleos(t)ide analogues (NAs), most patients with chronic hepatitis B (CHB) have achieved sustained viral control. The role of non-viral factors, especially modifiable factors, is anticipated to be reinforced in the future. Herein, we reviewed the modifiable non-viral risk factors of HBV-related HCC, in the hope of providing substantial evidence for further development of novel precautionary measures for HCC. In addition, the therapeutic interventions for reducing the risk of HCC, like potential conventional pharmaceutical interventions and lifestyle modification are also discussed in this review. Future studies that would explore the specific mechanism of HBV-related HCC development in patients with satisfactory viral control and related precision treatment are warranted.

Magnitude of and prediction for risk of hepatocellular carcinoma in patients with chronic hepatitis B taking entecavir or tenofovir therapy: A systematic review

BACKGROUND AND AIM

Entecavir (ETV) and tenofovir disoproxil fumarate (TDF) have been shown to reduce incidence of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B (CHB). This systematic review aims to evaluate the magnitude, change over time, and prediction of residual HCC risks in CHB patients treated with ETV/TDF therapy.

METHODS

Available literature was systematically reviewed through searches of PubMed and EMBASE databases from January 1, 2006 to September 1, 2019, to identify cohort studies that reported HCC incidence in CHB patients during ETV/TDF therapy. Studies were screened by title and abstract and then evaluated for eligibility in terms of full text.

RESULTS

We identified 141 studies for full-text review, and 34 were eligible for analysis. From 19 studies with data separated by cirrhosis status, the 5-year cumulative incidence of HCC was 0.5-6.9% in patients without cirrhosis, 4.5-21.6% in compensated cirrhosis, and 36.3-46.5% in decompensated cirrhosis. All four studies that addressed temporal changes in HCC risks consistently found the incidence rate decreased over time in patients with cirrhosis, although the findings were inconsistent in patients without cirrhosis. Six predictive scores were developed and validated to predict incident HCC during ETV/TDF therapy in CHB patients. Common scoring variables included age, sex, cirrhosis (fibrosis grade), and hepatic function. Conflicting results were reported in seven individual studies and two meta-analyses that compared ETV versus TDF.

CONCLUSIONS

The residual risk of HCC remains during ETV/TDF treatment in CHB patients with cirrhosis but declines over time. Risk stratification is attainable by validated predictive scores.

Recent Advances in Understanding, Diagnosing, and Treating Hepatitis B Virus Infection

Chronic hepatitis B virus (HBV) infection affects 292 million people worldwide and is associated with a broad range of clinical manifestations including cirrhosis, liver failure, and hepatocellular carcinoma (HCC). Despite the availability of an effective vaccine HBV still causes nearly 900,000 deaths every year. Current treatment options keep HBV under control, but they do not offer a cure as they cannot completely clear HBV from infected hepatocytes. The recent development of reliable cell culture systems allowed for a better understanding of the host and viral mechanisms affecting HBV replication and persistence. Recent advances into the understanding of HBV biology, new potential diagnostic markers of hepatitis B infection, as well as novel antivirals targeting different steps in the HBV replication cycle are summarized in this review article.

Validation of hepatocellular carcinoma risk scores in Japanese chronic hepatitis B cohort receiving nucleot(s)ide analog

BACKGROUND AND AIM

The prediction of hepatocellular carcinoma (HCC) development during nucleotide/nucleoside analog (NA) therapy is clinically important in patients with chronic hepatitis B. Although several useful models for HCC prediction have been previously reported, their usefulness in the Japanese population is unclear. Therefore, this study examines the applicability of these models in Japanese patients.

METHODS

Four hundred forty-three patients with no history of HCC who were treated with entecavir, tenofovir alafenamide, or tenofovir disoproxil fumarate were enrolled. PAGE-B, modified-PAGE-B, and REACH-B scores were calculated, and subsequent HCC development was investigated.

RESULTS

The mean follow-up duration was 5.1 years, and a total of 33 patients (7.4%) developed HCC during the follow-up period. Multivariate analysis revealed that old age (hazard ratio [HR] 1.05, 95% confidence interval [CI] 1.01-1.09, P = 0.011), male gender (HR 2.62, 95% CI 1.06-6.49, P = 0.037), and low platelet count (HR 0.83, 95% CI 0.77-0.91, P < 0.001) were independent predictors of HCC development. These factors are the same as the factors identified in the PAGE-B model. Time-dependent area under the receiver operating characteristic (AUROC) curve revealed that the AUROCs for 3 and 7 years of PAGE-B (AUROC: 0.786 and 0.744 at 3 and 7 years, respectively) were continuously higher than those of REACH-B (0.658 and 0.543) and modified PAGE-B AUROC (0.772 and 0.731).

CONCLUSIONS

PAGE-B, which can easily identify high-risk cases, can be useful for predicting HCC development in Japanese patients treated with NA therapy.