Hepatitis B: From control to cure

Hepatitis B Virus DNA Integration, Chronic Infections and Hepatocellular Carcinoma

Hepatitis B Virus (HBV) is an Old World virus with a high mutation rate, which puts its origins in Africa alongside the origins of Homo sapiens, and is a member of the Hepadnaviridae family that is characterized by a unique viral replication cycle. It targets human hepatocytes and can lead to chronic HBV infection either after acute infection via horizontal transmission usually during infancy or childhood or via maternal-fetal transmission. HBV has been found in ~85% of HBV-related Hepatocellular Carcinomas (HCC), and it can integrate the whole or part of its genome into the host genomic DNA. The molecular mechanisms involved in the HBV DNA integration is not yet clear; thus, multiple models have been described with respect to either the relaxed-circular DNA (rcDNA) or the double-stranded linear DNA (dslDNA) of HBV. Various genes have been found to be affected by HBV DNA integration, including cell-proliferation-related genes, oncogenes and long non-coding RNA genes (lincRNAs). The present review summarizes the advances in the research of HBV DNA integration, focusing on the evolutionary and molecular side of the integration events along with the arising clinical aspects in the light of WHO's commitment to eliminate HBV and viral hepatitis by 2030.

Combined viral quasispecies diversity and hepatitis B core-related antigen predict off-nucleos(t)ide analog durability in HBeAg-negative patients

BACKGROUND

Viral quasispecies dynamics between pre- and post-nucleos(t)ide analog (NA) therapy remains unclear.

AIM

This study aimed to investigate the HBV quasispecies evolution and its relationship with durability of off-therapy responses in HBeAg-negative chronic hepatitis B (CHB) patients who stopped NA therapy.

METHODS

Fifty-four HBeAg-negative CHB patients who stopped NAs, including 19 virological controllers (VC) who maintained serum HBV DNA < 2000 IU/mL beyond 1-year off-therapy, and 35 virological relapsers (VR) experiencing virological relapse within 1-year off-therapy were recruited. Viral quasispecies was analyzed by deep sequencing. Hepatitis B core-related antigen (HBcrAg) and HBsAg were also measured.

RESULTS

VC had significantly higher baseline viral quasispecies diversity of the precore/core gene, measured by nucleotide diversity, than VR. Low baseline viral nucleotide diversity (< 0.01) and high HBcrAg (≧ 2.0 KU/mL), but not HBsAg, at end of treatment (EOT) were significantly associated with higher risk of 1-year virological relapse (hazard ratio [HR] 6.09 and 3.31, respectively). Combination of low baseline viral nucleotide diversity and high HBcrAg at EOT could identify patients at high risk (HR 15.82). Further analysis of the evolution of HBV whole genome showed that HBV nucleotide diversity negatively correlated with serum HBV DNA levels. Notably, the viral quasispecies diversity between pre- and post-NA treatment remained relatively unchanged.

CONCLUSION

Higher baseline HBV quasispecies diversity associates with more durable off-therapy viral suppression in HBeAg-negative CHB patients. Combination of baseline viral nucleotide diversity and HBcrAg at EOT can identify patients at high risk for virological relapse after stopping NAs.

Baseline Mac-2 Binding Protein Glycosylation Isomer Level Stratifies Risks of Hepatocellular Carcinoma in Chronic Hepatitis B Patients with Oral Antiviral Therapy

BACKGROUND AND AIMS

Mac-2 binding protein glycosylation isomer (M2BPGi) is a novel biomarker correlating with liver fibrosis stages. However, little is known about how it predicts risks of hepatocellular carcinoma (HCC) in chronic hepatitis B (CHB) patients receiving long-term antiviral treatment.

MATERIALS AND METHODS

The study contained 2 parts. The first part was to explore whether M2BPGi could be an HCC predictor in 899 CHB patients receiving long-term entecavir therapy. The second part was to validate the findings in an independent cohort of 384 on-treatment CHB patients with more severe liver disease.

RESULTS

In the discovery cohort, there were 64 patients developing HCC within an average follow-up of 7.01 years. Our data showed that M2BPGi level was positively associated with HCC development. When stratifying the patients by an M2BPGi level of 1.73 (the third quartile), the high M2BPGi group was shown to have an increased HCC risk compared to the low M2BPGi group with hazard ratio of 5.80 (95% CI 3.50-9.60). Furthermore, we found that the M2BPGi level complements PAGE-B score, a well-validated HCC prediction model, to predict HCC development. Lastly, the cutoff was validated in the independent cohort, especially those with an intermediate PAGE-B score.

CONCLUSIONS

In CHB patients receiving long-term antiviral treatment, serum M2BPGi level not only serves as an independent HCC predictor but also complements PAGE-B in stratifying HCC risks.

Progress towards elimination goals for viral hepatitis

The global burden of viral hepatitis is substantial; in terms of mortality, hepatitis B virus and hepatitis C virus infections are on a par with HIV, malaria and tuberculosis, among the top four global infectious diseases. In 2016, the 194 Member States of the World Health Organization committed to eliminating viral hepatitis as a public health threat by 2030, with a particular focus on hepatitis B virus and hepatitis C virus infection. With only 10 years to go until the 2030 deadline is reached, and although much progress has been made towards elimination, there are still some important gaps in terms of policy and progress. In this Viewpoint, we asked a selection of scientists and clinicians working in the viral hepatitis field for their opinions on whether elimination of viral hepatitis by 2030 is feasible, what the key areas of progress are and what the focus for the next 10 years and beyond should be for viral hepatitis elimination.

High Level of Hepatitis B Core-Related Antigen Associated With Increased Risk of Hepatocellular Carcinoma in Patients With Chronic HBV Infection of Intermediate Viral Load

BACKGROUND & AIMS

Chronic hepatitis B virus (HBV) infection is a risk factor for hepatocellular carcinoma (HCC). Serum levels of HB core-related antigen (HBcrAg) have been associated with active replication of HBV. We investigated whether HBcrAg levels are associated with development of HCC, especially in patients who do not require antiviral treatment.

METHODS

We collected data from 2666 adults positive for hepatitis B surface antigen (HBsAg), infected with HBV genotypes B or C, and without liver cirrhosis, who had long-term follow-up at the National Taiwan University Hospital from 1985 through 2000. None of the patients received antiviral treatment during the follow-up. Baseline levels of HBV DNA, HBsAg, and HBcrAg were determined retrospectively and participants were followed for a mean of 15.95 years. The primary end point was an association between serum level of HBcrAg and HCC development.

RESULTS

HCC developed in 209 patients in the cohort (incidence rate, 4.91 cases/1000 person-years). We found a positive association between baseline level of HBcrAg and HCC development; HBcrAg level was an independent risk factor in multivariable analysis. In the subgroup of hepatitis B e antigen-negative patients with HBV DNA levels from 2000 to 19,999 IU/mL (intermediate viral load [IVL]) and normal levels of alanine aminotransferase, HBcrAg levels of 10 KU/mL or more identified patients at increased risk of HCC (hazard ratio, 6.29; confidence interval, 2.27-17.48). Patients with an IVL and a high level of HBcrAg had a risk for HCC that did not differ significantly from that of patients with a high viral load (≥20,000 IU/mL). Patients with an IVL but a low level of HBcrAg had a low risk of HCC, with an annual incidence rate of 0.10% (95% confidence interval, 0.04%-0.24%).

CONCLUSIONS

In a long-term follow-up study of 2666 patients with chronic HBV infection (genotypes B or C), level of HBcrAg is an independent risk factor of HCC. Moreover, HBcrAg level of 10 KU/mL identifies patients with an IVL who are at high risk for HCC.

Chronic hepatitis B is associated with an increased risk of B-cell non-Hodgkin's lymphoma and multiple myeloma

BACKGROUND

Chronic hepatitis B has been linked to lymphoma with contradictory results.

AIM

To investigate the association between chronic hepatitis B and lymphoma by using a nationwide population-based cohort.

METHODS

Records of patients diagnosed with chronic hepatitis B (hepatitis B virus [HBV] cohort) or without (non-HBV cohort) during 2004-2007 were retrieved from the Taiwan National Health Insurance Research Database. Age, sex, comorbidities, and medical visits were matched using propensity scores between both cohorts, and they were followed up longitudinally until 2012 to determine any new lymphoma development.

RESULTS

A total of 203 031 patients were included in each cohort with a mean follow-up of 7-9 years. The lymphoma incidence rate was significantly higher in the HBV cohort than in the non-HBV cohort (29.4 vs 15.9 per 100 000 person-years, P < 0.0001). After adjustment for comorbidities and medical visits, HBV infection was found to be an independent risk factor associated with the development of lymphoma (hazard ratio [HR]: 2.07, 95% confidence interval [CI]: 1.76-2.43, P < 0.0001) and non-Hodgkin's lymphoma (HR: 2.18, 95% CI: 1.80-2.65, P < 0.0001); specifically with an increased risk of diffuse large B-cell lymphoma (HR: 2.69, 95% CI: 2.05-3.52, P < 0.0001), other B-cell lymphoma (HR: 3.11, 95% CI: 1.89-5.11, P < 0.0001), and also for multiple myeloma (HR: 1.63, 95% CI: 1.10-2.42, P = 0.016). The association was significant even after excluding lymphoma development within the first year (HR: 2.08, 95% CI: 1.75-2.47, P < 0.0001).

CONCLUSIONS

Chronic hepatitis B is temporally associated with a 2-fold increased risk of lymphoma, particularly with B-cell non-Hodgkin's lymphoma, and also an increased risk for multiple myeloma.

Taiwan consensus statement on the management of chronic hepatitis B

The experts of Taiwan Association for the Study of Liver (TASL) have actively participated and led the guidelines on hepatitis B virus (HBV) management by Asian Pacific Association for the Study of Liver (APASL) which is the first international association for the study of liver to publish the statement on HBV management before. However, there are more and more new data on the natural history and treatment of HBV infection in the past decade. These include new application of an old biomarker (quantitative HBsAg), clinical significance of HBV genotype and naturally occurring mutations, the role of non-invasive examination in evaluating severity of hepatic fibrosis, clinical significance of outcome calculators, new drug or new combination strategies towards more effective therapy and organ transplantation including liver and non-liver transplantation. It is time to publish the guidelines on HBV management of Taiwan. Hence, TASL have conducted an expert meeting to review, to discuss and to debate the relevant literatures, followed by draft the manuscript of HBV management guidelines and recommendations. The guidelines include general management, indications for fibrosis assessment, time to start or stop drug therapy, choice of drug to initiate therapy, when and how to monitor the patients during and after stopping drug therapy. Recommendations on the therapy of patients in special circumstances, including women in childbearing age, patients with antiviral drug resistance, concurrent viral infection, hepatic decompensation, patient receiving immune suppression or chemotherapy and patients in the setting of liver transplantation and hepatocellular carcinoma, are also included.