HBV genotypes: relevance to natural history, pathogenesis and treatment of chronic hepatitis B

Viral Hepatitis: Host Immune Interaction, Pathogenesis and New Therapeutic Strategies

Viral hepatitis is a major cause of liver illness worldwide. Despite advances in the understanding of these infections, the pathogenesis of hepatitis remains a complex process driven by intricate interactions between hepatitis viruses and host cells at the molecular level. This paper will examine in detail the dynamics of these host-pathogen interactions, highlighting the key mechanisms that regulate virus entry into the hepatocyte, their replication, evasion of immune responses, and induction of hepatocellular damage. The unique strategies employed by different hepatitis viruses, such as hepatitis B, C, D, and E viruses, to exploit metabolic and cell signaling pathways to their advantage will be discussed. At the same time, the innate and adaptive immune responses put in place by the host to counter viral infection will be analyzed. Special attention will be paid to genetic, epigenetic, and environmental factors that modulate individual susceptibility to different forms of viral hepatitis. In addition, this work will highlight the latest findings on the mechanisms of viral persistence leading to the chronic hepatitis state and the potential implications for the development of new therapeutic strategies. Fully understanding the complex host-pathogen interactions in viral hepatitis is crucial to identifying new therapeutic targets, developing more effective approaches for treatment, and shedding light on the mechanisms underlying progression to more advanced stages of liver damage.

Extrahepatic malignancies and antiviral drugs for chronic hepatitis B: A nationwide cohort study

BACKGROUND/AIMS

Chronic hepatitis B (CHB) is related to an increased risk of extrahepatic malignancy (EHM), and antiviral treatment is associated with an incidence of EHM comparable to controls. We compared the risks of EHM and intrahepatic malignancy (IHM) between entecavir (ETV) and tenofovir disoproxil fumarate (TDF) treatment.

METHODS

Using data from the National Health Insurance Service of Korea, this nationwide cohort study included treatment-naïve CHB patients who initiated ETV (n=24,287) or TDF (n=29,199) therapy between 2012 and 2014. The primary outcome was the development of any primary EHM. Secondary outcomes included overall IHM development. E-value was calculated to assess the robustness of results to unmeasured confounders.

RESULTS

The median follow-up duration was 5.9 years, and all baseline characteristics were well balanced after propensity score matching. EHM incidence rate differed significantly between within versus beyond 3 years in both groups (P<0.01, Davies test). During the first 3 years, EHM risk was comparable in the propensity score-matched cohort (5.88 versus 5.84/1,000 person-years; subdistribution hazard ratio [SHR]=1.01, 95% confidence interval [CI]=0.88-1.17, P=0.84). After year 3, however, TDF was associated with a significantly lower EHM incidence compared to ETV (4.92 versus 6.91/1,000 person-years; SHR=0.70, 95% CI=0.60-0.81, P<0.01; E-value for SHR=2.21). Regarding IHM, the superiority of TDF over ETV was maintained both within (17.58 versus 20.19/1,000 person-years; SHR=0.88, 95% CI=0.81-0.95, P<0.01) and after year 3 (11.45 versus 16.20/1,000 person-years; SHR=0.68, 95% CI=0.62-0.75, P<0.01; E-value for SHR=2.30).

CONCLUSION

TDF was associated with approximately 30% lower risks of both EHM and IHM than ETV in CHB patients after 3 years of antiviral therapy.

Personalized Antiviral Drug Selection in Patients With Chronic Hepatitis B Using a Machine Learning Model: A Multinational Study

INTRODUCTION

Tenofovir disoproxil fumarate (TDF) is reportedly superior or at least comparable to entecavir (ETV) for the prevention of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B; however, it has distinct long-term renal and bone toxicities. This study aimed to develop and validate a machine learning model (designated as Prediction of Liver cancer using Artificial intelligence-driven model for Network-antiviral Selection for hepatitis B [PLAN-S]) to predict an individualized risk of HCC during ETV or TDF therapy.

METHODS

This multinational study included 13,970 patients with chronic hepatitis B. The derivation (n = 6,790), Korean validation (n = 4,543), and Hong Kong-Taiwan validation cohorts (n = 2,637) were established. Patients were classified as the TDF-superior group when a PLAN-S-predicted HCC risk under ETV treatment is greater than under TDF treatment, and the others were defined as the TDF-nonsuperior group.

RESULTS

The PLAN-S model was derived using 8 variables and generated a c-index between 0.67 and 0.78 for each cohort. The TDF-superior group included a higher proportion of male patients and patients with cirrhosis than the TDF-nonsuperior group. In the derivation, Korean validation, and Hong Kong-Taiwan validation cohorts, 65.3%, 63.5%, and 76.4% of patients were classified as the TDF-superior group, respectively. In the TDF-superior group of each cohort, TDF was associated with a significantly lower risk of HCC than ETV (hazard ratio = 0.60-0.73, all P < 0.05). In the TDF-nonsuperior group, however, there was no significant difference between the 2 drugs (hazard ratio = 1.16-1.29, all P > 0.1).

DISCUSSION

Considering the individual HCC risk predicted by PLAN-S and the potential TDF-related toxicities, TDF and ETV treatment may be recommended for the TDF-superior and TDF-nonsuperior groups, respectively.

Inverse Propensity Score-Weighted Analysis of Entecavir and Tenofovir Disoproxil Fumarate in Patients with Chronic Hepatitis B: A Large-Scale Multicenter Study

Tenofovir disoproxil fumarate (TDF) is reportedly superior or at least comparable to entecavir (ETV) in preventing hepatocellular carcinoma (HCC) among chronic hepatitis B (CHB) patients; however, it remains controversial. This study aimed to conduct comprehensive comparisons between the two antivirals. CHB patients initially treated with ETV or TDF between 2012 and 2015 at 20 referral centers in Korea were included. The primary outcome was the cumulative incidence of HCC. The secondary outcomes included death or liver transplantation, liver-related outcome, extrahepatic malignancy, development of cirrhosis, decompensation events, complete virologic response (CVR), seroconversion rate, and safety. Baseline characteristics were balanced using the inverse probability of treatment weighting (IPTW). Overall, 4210 patients were enrolled: 1019 received ETV and 3191 received TDF. During the median follow-ups of 5.6 and 5.5 years, 86 and 232 cases of HCC were confirmed in the ETV and TDF groups, respectively. There was no difference in HCC incidence between the groups both before (p = 0.36) and after IPTW was applied (p = 0.81). Although the incidence of extrahepatic malignancy was significantly higher in the ETV group than in the TDF group before weighting (p = 0.02), no difference was confirmed after IPTW (p = 0.29). The cumulative incidence rates of death or liver transplantation, liver-related outcome, new cirrhosis development, and decompensation events were also comparable in the crude population (p = 0.24-0.91) and in the IPTW-adjusted population (p = 0.39-0.80). Both groups exhibited similar rates of CVR (ETV vs. TDF: 95.1% vs. 95.8%, p = 0.38), and negative conversion of hepatitis B e antigen (41.6% vs. 37.2%, p = 0.09) or surface antigen (2.8% vs. 1.9%, p = 0.10). Compared to the ETV group, more patients in the TDF group changed initial antivirals due to side effects, including decreased kidney function (n = 17), hypophosphatemia (n = 20), and osteoporosis (n = 18). In this large-scale multicenter study, ETV and TDF demonstrated comparable effectiveness across a broad range of outcomes in patients with treatment-naïve CHB during similar follow-up periods.

Hepatitis B Virus Genotype D: An Overview of Molecular Epidemiology, Evolutionary History, and Clinical Characteristics

The hepatitis B virus (HBV) genotype D (HBV/D) is the most extensively distributed genotype worldwide with distinct molecular and epidemiological features. This report provides an up-to-date review on the history of HBV/D subgenotyping and misclassifications, along with large-scale analysis of over 1000 HBV/D complete genome sequences, with the aim of gaining a thorough understanding of the global prevalence and geographic distribution of HBV/D subgenotypes. We have additionally explored recent paleogenomic findings, which facilitated the detection of HBV/D genomes dating back to the late Iron Age and provided new perspectives on the origins of modern HBV/D strains. Finally, reports on distinct disease outcomes and responses to antiviral therapy among HBV/D subgenotypes are discussed, further highlighting the complexity of this genotype and the importance of HBV subgenotyping in the management and treatment of hepatitis B.

Hepatitis B virus haplotype number at baseline is a predictive marker of functional cure during antiviral therapy for patients with genotypes A and D HBeAg-positive chronic hepatitis B

BACKGROUNDS AND AIMS

We investigated associations between hepatitis B virus (HBV) genome-length haplotype number (HN) at baseline in subjects with HBeAg-positive chronic hepatitis B (CHB), and the likelihood of achieving functional cure during direct-acting antiviral therapy METHOD: We analysed 86 HBeAg-positive baseline samples from patients with HBV genotypes A and D who were enrolled in a Phase II trial of tenofovir disoproxil fumarate (TDF) to determine if HN was a biomarker of HBsAg loss during therapy. Findings were validated using baseline samples from 181 patients with HBV genotypes A and D from an independent clinical trial utilising TDF or tenofovir alafenamide therapy in HBeAg-positive CHB.

RESULTS

In the HBeAg-positive test cohort, patients with genotypes A or D and ≤2 haplotypes had a minimum of 21-fold higher likelihood of achieving HBsAg loss on TDF. Baseline HN (p < 0.0001) was a stronger predictor of HBsAg loss on therapy than HBsAg titre (p = 0.03), HBeAg titre (p = 0.0002), or the presence of HBV basal core promoter (A1762T, p = 0.0379 and G1764A, p = 0.0176) or G1896A precore mutations (p = 0.0218). This finding was validated in the independent validation cohort. HN was statistically higher in patients with HBV genotypes B or C infection compared to genotypes A and D.

CONCLUSION

Baseline HN ≤2 predicts which patients with HBV genotypes A or D will more likely progress to functional cure on current direct-acting antiviral therapy, with greater accuracy than current biomarkers including baseline HBsAg and HBeAg titre.

Metabolic dysfunction associated fatty liver disease identifies subjects with cardiovascular risk better than non-alcoholic fatty liver disease

BACKGROUND AND AIMS

Cardiovascular disease (CVD) is the main cause of mortality in subjects with non-alcoholic fatty liver disease (NAFLD). We investigated the association between CVD risk and metabolic dysfunction-associated fatty liver disease (MAFLD) or NAFLD and the influence of significant liver fibrosis on the CVD risk.

METHODS

Subjects who underwent a comprehensive medical check-up were recruited (2014-2019). Significant liver fibrosis was defined using NAFLD fibrosis score, fibrosis-4 index, aspartate aminotransferase to platelet ratio index, or FibroScan-aspartate aminotransferase score. High probability of atherosclerotic CVD (ASCVD) was defined as ASCVD risk score > 10%.

RESULTS

Of the study population (n = 78 762), 27 047 (34.3%) and 24 036 (30.5%) subjects had MAFLD and NAFLD respectively. A total of 1084 (4.0%) or 921 (3.8%) subjects had previous CVD history in MAFLD or NAFLD subgroup respectively. The previous CVD history and high probability of ASCVD were significantly higher in MAFLD or NAFLD subgroup with significant liver fibrosis than in the other groups (all p < .001). In multivariable analysis, MAFLD was independently associated with previous CVD history after adjusting for confounders (adjusted odds ratio [aOR] = 1.10, p = .038), whereas NAFLD was not (all p > .05). MAFLD (aOR = 1.40) or NAFLD (aOR = 1.22) was independently associated with high probability of ASCVD after full adjustment respectively (all p < .001). Significant liver fibrosis was independently associated with previous CVD history and high probability of ASCVD after adjustment in MAFLD or NAFLD subgroup respectively (all p < .05).

CONCLUSION

MAFLD might better identify subjects with CVD risk than NAFLD. Fibrosis assessment might be helpful for detailed prognostication in subjects with MAFLD.

Alanine aminotransferase levels as therapeutic targets after nucleotide/nucleoside analog therapy in patient with chronic hepatitis B

AIM

Alanine aminotransferase (ALT) is a criterion for the introduction of nucleotide/nucleoside analog (NA), and ALT levels are decreased by NA treatment. However, the association between post-treatment ALT levels and hepatocellular carcinoma (HCC) risk remains unclear. To fill this gap, we aimed to establish a target value of ALT level during NA treatment.

METHODS

In total, 413 patients with chronic hepatitis B who received entecavir, tenofovir alafenamide, or tenofovir disoproxil fumarate were enrolled. The subsequent development of HCC was examined and a target value of ALT level during NA treatment as a risk marker for HCC was evaluated.

RESULTS

The median follow-up duration was 5.1 years, during which time 27 patients (8.6%) developed HCC. ALT level at the start of treatment was not associated with HCC development (p = 0.08). When stratified by ALT at 1 year after NA initiation, the cumulative 3- and 5-year rates of HCC for patients with ALT ≥21 IU/L were 11.5% and 18.1%, and those with ALT <21 IU/L was 2.3% and 6.5%, respectively. Patients with ALT <21 IU/L had a significantly lower risk of HCC development compared with patients with ALT ≥21 IU/L (p = 0.002). In multivariable analysis adjusting age, sex, and platelet counts, ALT ≥21 IU/L was an independent risk factor of HCC development with hazard ratio of 4.5 (95% confidence interval: 1.01-20.4).

CONCLUSIONS

ALT <21 IU/L at 1 year after NA initiation has a lower risk of HCC and could be used as a target value for NA treatment.

Prevalence and Risk Factors of Cardiovascular Disease in Patients with Chronic Hepatitis B

BACKGROUND

The association between chronic hepatitis B (CHB) and cardiovascular disease (CVD) remains unclear. We investigated the prevalence and risk factors of CVD in patients with CHB.

METHODS

Data from the Korean National Health and Nutrition Examination Surveys 2008-2011 were analyzed. Significant liver fibrosis was defined as the highest nonalcoholic fatty liver disease fibrosis score quartile, highest Forns index quintile, or fibrosis-4 ≥ 2.67. The CVD risk was calculated using the 10-year atherosclerotic cardiovascular disease (ASCVD) risk score from the 2013 ACC/AHA Guidelines.

RESULTS

Among the 506 subjects with CHB, 15 (3.0%) and 150 (29.6%) patients had a CVD history and significant liver fibrosis, respectively. Patients with CVD history were significantly older; showed a significantly higher prevalence of hypertension, metabolic syndrome, and significant liver fibrosis; and had a significantly higher platelet count, lower aspartate and alanine aminotransferase levels, higher triglyceride level, lower high-density lipoprotein level, and higher ASCVD risk than those without (all p < 0.05). In multivariate analysis, higher ASCVD risk (odds ratio [OR] = 1.090) and significant liver fibrosis (OR = 4.341) independently predicted the risk of CVD history (p < 0.05). The prevalence of CVD risk (6.7% vs. 1.4%; OR = 5.014) and high ASCVD risk (> 15%) (34.0% vs. 7.3%; OR = 6.538) was significantly higher in patients with significant liver fibrosis than in those without (all p < 0.05).

CONCLUSIONS

Significant liver fibrosis was independently associated with the risk of CVD history in patients with CHB. Prospective studies are needed to validate the longitudinal association between fibrotic burden and CVD development in patients with CHB.

Virological Treatment Monitoring for Chronic Hepatitis B

More than 250 million people worldwide are currently infected with hepatitis B, despite the effectiveness of vaccination and other preventive measures. In terms of treatment, new therapeutic approaches are rapidly developing, promising to achieve the elimination of infected cells and the complete cure of infection. The on-treatment monitoring of these innovative antiviral treatments will require the implementation of new virological tools. Therefore, new biomarkers are being evaluated besides the traditional virological and serological assays in order to obtain information on different steps of the viral replication cycle and to monitor response to therapy more accurately. The purpose of this work is to describe both standard and innovative tools for chronic hepatitis B treatment monitoring, and to analyse their potential and feasibility.

An artificial intelligence model to predict hepatocellular carcinoma risk in Korean and Caucasian patients with chronic hepatitis B

BACKGROUND & AIMS

Several models have recently been developed to predict risk of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B (CHB). Our aims were to develop and validate an artificial intelligence-assisted prediction model of HCC risk.

METHODS

Using a gradient-boosting machine (GBM) algorithm, a model was developed using 6,051 patients with CHB who received entecavir or tenofovir therapy from 4 hospitals in Korea. Two external validation cohorts were independently established: Korean (5,817 patients from 14 Korean centers) and Caucasian (1,640 from 11 Western centers) PAGE-B cohorts. The primary outcome was HCC development.

RESULTS

In the derivation cohort and the 2 validation cohorts, cirrhosis was present in 26.9%-50.2% of patients at baseline. A model using 10 parameters at baseline was derived and showed good predictive performance (c-index 0.79). This model showed significantly better discrimination than previous models (PAGE-B, modified PAGE-B, REACH-B, and CU-HCC) in both the Korean (c-index 0.79 vs. 0.64-0.74; all p <0.001) and Caucasian validation cohorts (c-index 0.81 vs. 0.57-0.79; all p <0.05 except modified PAGE-B, p = 0.42). A calibration plot showed a satisfactory calibration function. When the patients were grouped into 4 risk groups, the minimal-risk group (11.2% of the Korean cohort and 8.8% of the Caucasian cohort) had a less than 0.5% risk of HCC during 8 years of follow-up.

CONCLUSIONS

This GBM-based model provides the best predictive power for HCC risk in Korean and Caucasian patients with CHB treated with entecavir or tenofovir.

LAY SUMMARY

Risk scores have been developed to predict the risk of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B. We developed and validated a new risk prediction model using machine learning algorithms in 13,508 antiviral-treated patients with chronic hepatitis B. Our new model, based on 10 common baseline characteristics, demonstrated superior performance in risk stratification compared with previous risk scores. This model also identified a group of patients at minimal risk of developing HCC, who could be indicated for less intensive HCC surveillance.

Dried blood spot sampling for hepatitis B virus quantification, sequencing and mutation detection

Hepatitis B virus (HBV) diagnosis is performed on serum samples, but the access to this diagnosis is difficult in low-income regions. The use of dried blood spot (DBS) samples does not require special structure for collection, storage or transport. This study evaluates the use of DBS for detection, quantification and sequencing of HBV DNA using in-house techniques. Two study groups were included: 92 HBsAg + individuals and 49 negative controls. Serum and DBS samples were submitted to quantitative and qualitative in-house PCR for S/pol genes, sequencing and phylogenetic analyses. Total of 84 serum samples were successfully amplified. Of them, 63 paired DBS were also positive in qualitative PCR. Qualitative PCR in DBS presented a sensitivity of 75% and specificity of 100% (Kappa = 0.689). Quantitative PCR in DBS presented a detection limit of 852.5 copies/mL (250 IU/mL), sensitivity of 77.63% and specificity of 100% (Kappa = 0.731). A total of 63 serum samples and 36 DBS samples were submitted to sequencing, revealing the circulation of genotypes A (65.08%), D (4.8%), E (3.2%) and F (27%) with 100% of correspondence between serum and DBS. All sequenced samples displayed polymorphisms in HBsAg gene. An HIV-coinfected patient presented the rtM204V/I-rtL180M double resistance mutation in serum and DBS. In conclusion, DBS is an alternative to detect, quantify and characterize HBV DNA, being a possibility of increasing diagnosis in low-income settings, closing gaps in HBV control.

Efficacy and Safety of Tenofovir Disoproxil Orotate in Chronic Hepatitis B Patients Previously Treated with Tenofovir Disoproxil Fumarate: Multicenter, Open-Label, Prospective Study

Background/Aim: We aimed to demonstrate the efficacy and safety of tenofovir disoproxilorotate (TDO) compared with that of tenofovir disoproxil fumarate (TDF) in patients with chronic hepatitis B. Methods: This multicenter, open-label, prospective clinical trial (KCT0004185) was conducted to evaluate the efficacy and safety of TDO on switching from TDF for 24 weeks in virologically suppressed chronic hepatitis B patients. The primary efficacy endpoint was the maintenance of virologic response. Safety was assessed by evaluating major adverse events, changes in renal function, and occurrence of hepatocellular carcinoma (HCC). Results: TDO treatment was not inferior in terms of virological response when compared with that on TDF treatment, with a noninferiority margin of −10% (risk difference, −3.17%; 95% confidence interval, −7.5–1.15%). The biological response of TDO was also comparable to that of TDF, with no significant difference in the proportion of patients with normalized alanine transaminase levels. After 24 weeks of treatment, hepatitis B core-related antigen (HBcrAg) significantly decreased to a mean titer of 3.91 log U/mL from 4.15 log U/mL at baseline (p = 0.01). There were no cases of grade 3 or higher adverse events and HCC. The mean estimated glomerular filtration rate increased from 91.09 mL/min to 93.34 mL/min (p = 0.056), and the mean serum level of phosphorus increased from 3.33 mg/dL to 3.44 mg/dL (p = 0.045), suggesting improvement in renal function with TDO treatment. Conclusion: In patients with chronic hepatitis B, the efficacy of TDO was noninferior to that of TDF, with a significant decrease in the HBcrAg titer and improved renal function.

Biological Characterization of Hepatitis B virus Genotypes: Their Role in Viral Replication and Antigen Expression

Hepatitis B virus (HBV) inter-host evolution has resulted in genomic diversification reflected in the existence of nine genotypes (A-I) and numerous subgenotypes. There is growing evidence that genotypes influence HBV natural history, clinical outcomes, and treatment response. However, the biological characteristics underlying these differences have not yet been established. By transfecting HuH-7 cells with unit-length constructs of genotypes A2, B2, C1, D1, and F1b, we identified major differences in HBV replicative capacity and antigen expression across genotypes. Genotypes B2 and F1b showed a 2-fold increase in cccDNA levels compared to the other genotypes (p<0.005). Genotype A2 expressed the lowest pgRNA levels, with a 70-fold decrease in relation to the other genotypes (p<0.0001), while genotype B2 showed the lowest Precore RNA levels, with a 100-fold reduction compared to genotype A2 (p<0.0001). The highest intracellular HBV DNA levels were observed for genotype B2 and the lowest for genotypes A2 and C1 (p<0.0001). Regarding antigen expression, genotype F1b secreted the highest HBsAg levels and genotype D1 the lowest (p<0.0001), while genotypes A2 and B2 showed the highest intracellular HBsAg levels (p<0.0001). Interestingly, genotype C1 secreted the highest HBeAg levels, while genotype A2 showed the highest intracellular levels (p<0.0001). Finally, the analysis of the intra/extracellular antigen ratios revealed that most genotypes retained intracellularly 5-20% of the antigens, except the genotype A2 that retained 50% of the total expressed antigens. In conclusion, this study provides new insights into the biological characteristics of HBV genotypes, being the first study to comparatively analyze European (A and D) and Asian (B and C) genotypes with the Latin American (F) genotype. The differences in HBV replication and antigen expression might contribute to understand the differential role of genotypes in pathogenesis.

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

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

Impact of tenofovir alafenamide vs. entecavir on hepatocellular carcinoma risk in patients with chronic hepatitis B

BACKGROUND AND AIMS

Whether entecavir (ETV) or tenofovir alafenamide (TAF) is better at preventing hepatocellular carcinoma (HCC) development among patients with chronic hepatitis B (CHB) remains unclear. The present study was conducted to explore the ability of these two antivirals to prevent HCC.

METHODS

From 2012 to 2019, treatment-naïve CHB patients undergoing ETV or TAF therapy were recruited at three academic teaching hospitals. The TAF group comprised patients starting TAF as first-line antiviral and those switching antivirals from tenofovir disoproxil fumarate to TAF. Patients with decompensated cirrhosis or HCC at enrollment were excluded from the analysis. Cumulative probabilities of HCC were assessed using the Kaplan-Meier method.

RESULTS

In total, 1810 patients (1525 and 285 in ETV and TAF groups, respectively) were recruited. The annual HCC incidence was statistically not different between the ETV and TAF groups (1.67 vs. 1.19 per 100 person-years, respectively) with an adjusted hazard ratio (HR) of 0.681 (p = 0.255), as determined by multivariate analysis. Male, hypertension, liver cirrhosis, FIB-4 index, and albumin were independent prognostic factors for HCC development. Propensity score-matched and inverse probability of treatment weighting analyses yielded similar results, with non-statistically different HCC incidence between the ETV and TAF groups (1.07 vs. 1.19 per 100 person-years (HR = 0.973; p = 0.953) and 1.67 vs. 1.89 per 100 person-years, respectively (HR = 0.949; p = 0.743).

CONCLUSIONS

These findings suggest that ETV- and TAF-treated CHB patients have similar risk of developing HCC. Further studies with the larger sample size and longer follow-up are needed to validate these results.

Hepatitis B virus infection modeling using multi-cellular organoids derived from human induced pluripotent stem cells

Chronic infection with hepatitis B virus (HBV) remains a global health concern despite the availability of vaccines. To date, the development of effective treatments has been severely hampered by the lack of reliable, reproducible, and scalable in vitro modeling systems that precisely recapitulate the virus life cycle and represent virus-host interactions. With the progressive understanding of liver organogenesis mechanisms, the development of human induced pluripotent stem cell (iPSC)-derived hepatic sources and stromal cellular compositions provides novel strategies for personalized modeling and treatment of liver disease. Further, advancements in three-dimensional culture of self-organized liver-like organoids considerably promote in vitro modeling of intact human liver tissue, in terms of both hepatic function and other physiological characteristics. Combined with our experiences in the investigation of HBV infections using liver organoids, we have summarized the advances in modeling reported thus far and discussed the limitations and ongoing challenges in the application of liver organoids, particularly those with multi-cellular components derived from human iPSCs. This review provides general guidelines for establishing clinical-grade iPSC-derived multi-cellular organoids in modeling personalized hepatitis virus infection and other liver diseases, as well as drug testing and transplantation therapy.

Cost-effectiveness of adding a birth dose of hepatitis B vaccine in the Dafra district of the Hauts-Bassins Region in Burkina Faso (NéoVac Study)

BACKGROUND

The World Health Organization (WHO) recommends a first hepatitis B vaccine dose within 24 h of birth (HepB-BD) to prevent mother-to-child transmission. Evidence for this strategy's economic value in Africa is limited. We assessed the costs and cost-effectiveness of adding HepB-BD to the current three-dose pentavalent schedule (HepB3) in the Dafra district of the Hauts-Bassins Region in Burkina Faso.

METHODS

Using a decision tree combined with a Markov model, we estimated the expected number of life-years (LY) and disability-adjusted life-years (DALYs) saved, incremental costs, and incremental cost-effectiveness ratios (ICER) of HepB-BD + HepB3 versus HepB3 alone in Dafra's 2017 birth cohort (n = 11,462). Institutional delivery rates, vaccine coverage, and vaccination costs from a health system perspective were estimated from field-collected data. We estimated the effectiveness of HepB-BD, age-specific transition probabilities, and horizontal transmission risks using data from previous African studies. Costs and health outcomes were discounted at an annual rate of 3%. We conducted one-way and probabilistic sensitivity analyses to assess uncertainty.

RESULTS

In the base-case analysis without discounting, HepB-BD + HepB3 yielded a net cost saving of US$18,979 and saved 163 DALYs compared with HepB3 alone. With discounting, HepB-BD + HepB3 compared with HepB3 resulted in an incremental cost of US$554 and 31 DALYs averted, translating into an ICER of US$18/DALY averted. In one-way sensitivity analyses, HepB-BD + HepB3 remained cost-effective (at the cost-effectiveness threshold of US$671 i.e. the Burkina Faso per-capita gross domestic product) for all parameter changes. However, results were very sensitive to variations in HepB-BD unit cost per vaccinated neonate and perinatal transmission risk in mothers carrying the hepatitis B e antigen. The probabilities of HepB-BD + HepB3 being cost-effective were 71.7% and 86.7%, at the cost-effectiveness thresholds of US$335 and US$671, respectively.

CONCLUSION

Introducing HepB-BD in Burkina Faso is likely to be cost-effective.

The efficacies of entecavir and tenofovir in terms of enhancing prognosis after curative treatment of hepatitis B virus-related hepatocellular carcinoma

BACKGROUND/AIMS

Whether entecavir (ETV) or tenofovir disoproxil fumarate (TDF) affords the better prognosis after curative treatment of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) remains unclear. We compared recurrence and death rates between patients taking ETV and those taking TDF.

METHODS

Between 2013 and 2017, patients with HBV-related HCC who had undergone hepatic resection (n=421) or radiofrequency ablation (n=305) as first-line anti-HCC treatment in three institutes were consecutively enrolled. All patients received ETV or TDF as a first-line antiviral. The cumulative probabilities of recurrence and death were assessed. We adjusted for viral factors, including the HBV-DNA load, and tumor and demographic factors.

RESULTS

During the study period (median 46.6 [interquartile range 25.3-58.9] months), 227 patients experienced recurrence and 53 died. In the ETV (n=405) and TDF (n=321) groups, the annual incidences of recurrence (10.61 and 11.21 per 100 person-years, respectively; P=727) and death (2.28 and 1.79 per 100 person-years, respectively; P=277) were similar, with adjusted hazard ratios (aHRs) of 0.932 (P=0.622) and 0.667 (P=0.193), respectively. When stratified by treatment modality and the timing of antiviral therapy commencement, the values were similar (all P>0.05). Inverse probability of treatment weighting (IPTW) analyses yielded results that were similar in the two groups in terms of recurrence (aHR=1.038, P=0.963) and death (aHR=0.799, P=0.431). Furthermore, the early (<2 years) and late (≥2 years) recurrence risks were not statistically different in the two groups (both P=0.400), as confirmed by IPTW analysis (P=0.502 and P=0.377, respectively).

CONCLUSIONS

The prognoses in terms of recurrence and death after curative treatment of HBV-related HCC were not statistically different between the ETV and TDF groups. Further validation studies are needed.

Entecavir versus tenofovir in patients with chronic hepatitis B: Enemies or partners in the prevention of hepatocellular carcinoma

Over the past several decades, entecavir (ETV) and tenofovir disoproxil fumarate (TDF) have remained the first-line antiviral agents in several international guidelines. These two antiviral agents have shown similar short to intermediateterm efficacy, including virologic, biochemical, serologic, and histologic responses. However, huge controversies regarding the antiviral efficacy of ETV and TDF in preventing the development of hepatocellular carcinoma (HCC) still exist. In this review, we summarized recent studies that compared the treatment efficacy of ETV and TDF in terms of HCC development.

External validation of CAGE-B and SAGE-B scores for Asian chronic hepatitis B patients with well-controlled viremia by antivirals

CAGE-B and SAGE-B scores, consisting of age and fibrotic burden as cirrhosis and/or liver stiffness, were recently proposed to predict hepatocellular carcinoma (HCC) risk among Caucasian chronic hepatitis B (CHB) patients undergoing long-term antiviral therapy. We externally validated their predictive performances among an independent cohort from Asia, compared to other conventional prediction models. We consecutively recruited CHB patients with well-controlled viremia (serum HBV DNA < 2000 IU/mL) receiving antiviral therapy. Patients with decompensated cirrhosis or HCC at baseline were excluded. Among 1763 patients, CAGE-B score provided the highest Heagerty's integrated area under the curve (iAUC) (0.820), followed by SAGE-B (0.804), mREACH-B (0.800), CAMD (0.786), mPAGE-B (0.748) and PAGE-B (0.721) scores. CAGE-B score showed a significantly better performance than SAGE-B, CAMD, PAGE-B and mPAGE-B scores, but was similar to mREACH-B. SAGE-B score also showed significantly better performance than mPAGE-B and PAGE-B, but was similar to CAMD and mREACH-B. According to CAGE-B score 0-5, 6-10 and ≥11, the annual HCC incidences were 0.18, 1.34 and 6.03 per 100 person-years, respectively (all p < 0.001 between each pair). Likewise, by SAGE-B score 0-5, 6-10 and ≥11, those were 0.31, 1.49 and 8.96 per 100 person-years, respectively (all p < 0.001 between each pair). Hence, CAGE-B and SAGE-B scores showed acceptable predictive performances for Asian CHB patients undergoing antiviral therapy, with the higher performance by CAGE-B score. They show a trend towards better prognostic capability to predict HCC risk than previous models.

Natural History of Untreated HBeAg-Positive Chronic HBV Infection With Persistently Elevated HBV DNA but Normal Alanine Aminotransferase

Nucleos(t)ide analogues (NUCs) are not routinely recommended for patients with hepatitis B e antigen–positive chronic hepatitis B virus (HBV) infection who have persistently elevated serum HBV DNA level (>20,000 IU/mL) but normal alanine aminotransferase (<40 IU/L) level. Here, we evaluated the cumulative risks of hepatocellular carcinoma (HCC) in such patients (the untreated persistently elevated serum HBV DNA [pEDNA] group) compared with inactive carriers (the IC group).

Analysis of Hepatitis B Virus Haplotype Diversity Detects Striking Sequence Conservation Across Genotypes and Chronic Disease Phase

BACKGROUND AND AIMS

We conducted haplotype analysis of complete hepatitis B virus (HBV) genomes following deep sequencing from 368 patients across multiple phases of chronic hepatitis B (CHB) infection from four major genotypes (A-D), analyzing 4,110 haplotypes to identify viral variants associated with treatment outcome and disease progression.

APPROACH AND RESULTS

Between 18.2% and 41.8% of nucleotides and between 5.9% and 34.3% of amino acids were 100% conserved in all genotypes and phases examined, depending on the region analyzed. Hepatitis B e antigen (HBeAg) loss by week 192 was associated with different haplotype populations at baseline. Haplotype populations differed across the HBV genome and CHB history, this being most pronounced in the precore/core gene. Mean number of haplotypes (frequency) per patient was higher in immune-active, HBeAg-positive chronic hepatitis phase 2 (11.8) and HBeAg-negative chronic hepatitis phase 4 (16.2) compared to subjects in the "immune-tolerant," HBeAg-positive chronic infection phase 1 (4.3, P< 0.0001). Haplotype frequency was lowest in genotype B (6.2, P< 0.0001) compared to the other genotypes (A = 11.8, C = 11.8, D = 13.6). Haplotype genetic diversity increased over the course of CHB history, being lowest in phase 1, increasing in phase 2, and highest in phase 4 in all genotypes except genotype C. HBeAg loss by week 192 of tenofovir therapy was associated with different haplotype populations at baseline.

CONCLUSIONS

Despite a degree of HBV haplotype diversity and heterogeneity across the phases of CHB natural history, highly conserved sequences in key genes and regulatory regions were identified in multiple HBV genotypes that should be further investigated as targets for antiviral therapies and predictors of treatment response.

Impact of antiviral therapy on risk prediction model for hepatocellular carcinoma development in patients with chronic hepatitis B

AIM

Risk prediction models for hepatocellular carcinoma (HCC) development are available. However, the influence of antiviral therapy (AVT) on these models in patients with chronic hepatitis B is unknown.

METHODS

The dynamic changes in risk prediction models during AVT and the association between risk prediction model and the risk of chronic hepatitis B-related HCC development were investigated. Between 2005 and 2017, 4917 patients with chronic hepatitis B (3361 noncirrhotic, 1556 cirrhotic) were recruited.

RESULTS

The mean age of the study population was 49.3 years and 60.6% (n = 2980) of the patients were male. The mean Chinese University-HCC (CU-HCC) score was 12.7 at baseline in the overall study population, and decreased significantly (mean, 8.7) after 1 year of AVT (p < 0.001). The score was maintained throughout 5 years of AVT (mean, 8.4-8.8; p > 0.05). The proportion of high-risk patients (CU-HCC score ≥ 20) was 28.9% at baseline, and decreased significantly after 1 year of AVT (5.0%; p < 0.001), and remained stable through 5 years of AVT (2.2%-3.6%; p > 0.05). In addition to the score at baseline, the CU-HCC score at 1 year of AVT independently predicted the risk of HCC development (hazard ratio = 1.072; p < 0.001), together with male gender and platelet count (all p < 0.05).

CONCLUSIONS

The CU-HCC score significantly decreased at 1 year of AVT and was maintained thereafter. The CU-HCC score after 1 year of AVT independently predicted the risk of HCC development in patients with chronic hepatitis B.

Negligible HCC risk during stringently defined untreated immune-tolerant phase of chronic hepatitis B

BACKGROUND & AIMS

Whether chronic hepatitis B (CHB) patients during immune-tolerant (IT) phase are at low risk of hepatocellular carcinoma (HCC) is still controversial. We performed a multicenter study to determine their long-term prognosis.

METHODS

Untreated IT group included patients < 40 years of age, with persistently hepatitis B e antigen [HBeAg] positivity, serum HBV-DNA>6 log₁₀IU/mL, and ALT level < 40 U/L, using age and HBV-DNA criteria by the American Association for the Study of Liver Diseases (AASLD) guideline. Cumulative HCC risk of untreated IT group (n=194) was compared to HBeAg-positive patients undergoing antiviral therapy according to the practice and reimbursement guidelines (treated HBeAg[+] group, n=454). Patients with history of cirrhosis or HCC at baseline were excluded.

RESULTS

During follow-up (median 62.1 months), HCC did not develop in any patient among untreated IT group, whereas the cumulative probability of HCC at 3, 5, and 9 years in the treated HBeAg(+) group was 0.5%, 0.7%, and 1.3%, respectively (p=0.203). Ninety-seven patients among untreated IT group entered immune-active phase, of whom 86 (88.7%) started antiviral treatment. A high normal ALT level (20-39 U/L) was associated with an increased risk of a phase change, compared to ALT < 20 U/L. After censoring at the time of phase change, the cumulative HCC risk was also not significantly different between two groups (p=0.258).

CONCLUSIONS

No actual HCC risk during untreated IT phase defined by age and HBV-DNA criteria of the AASLD guideline exists, supporting their diagnostic validity from the perspective of long-term prognosis. Further validation studies are required.

Effectiveness of entecavir in preventing hepatocellular carcinoma development is genotype-dependent in hepatitis B virus-associated liver cirrhosis

BACKGROUND

The oral nucleos(t)ide analogue, entecavir (ETV) was demonstrated to reduce the rate of hepatocellular carcinoma (HCC) in patients with hepatitis B virus (HBV)-associated liver cirrhosis. However, the reduction of HCC differs in various regions of the world.

AIM

To investigate the reduction of HCC development due to ETV therapy by meta-analysis.

METHODS

We surveyed the differences in HCC development following ETV treatment based on published articles using PubMed (2004-2019).

RESULTS

The regions with the most marked reduction in HCC development due to ETV therapy were Spain (1.0%/year) and Canada (Southern part, 1.3%/year), and the most ineffective areas were South Korea (3.6%-3.8%/year), China (3.3%/year), Taiwan (2.4%-3.1%/year), and Hong Kong (2.8%/year). Following ETV administration, the incidence of HCC in genotype D regions (1.89% ± 0.28%/year, mean ± SE) was significantly lower than that in genotype C regions (2.91% ± 0.24%/year, P < 0.01). With regard to the initial HBV-DNA level, in genotype C patients (average: 5.61 Log₁₀IU/mL) this was almost the same as that in genotype D patients (average: 5.46 Log₁₀IU/mL). Moreover, there was no association between the prevalence ratio of HBV and the incidence of HCC on ETV treatment.

CONCLUSION

The effectiveness of ETV in preventing HCC development in HBV-associated liver cirrhosis is genotype-dependent.

Long-term risk of primary liver cancers in entecavir versus tenofovir treatment for chronic hepatitis B

It remains controversial whether entecavir (ETV) and tenofovir disoproxil fumarate (TDF) is associated with different clinical outcomes for chronic hepatitis B (CHB). This study aimed to compare the long-term risk of ETV versus TDF on hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC) in CHB patients from a large multi-institutional database in Taiwan. From 2011 to 2018, a total of 21,222 CHB patients receiving ETV or TDF were screened for eligibility. Patients with coinfection, preexisting cancer and less than 6 months of follow-up were excluded. Finally, 7248 patients (5348 and 1900 in the ETV and TDF groups, respectively) were linked to the National Cancer Registry database for the development of HCC or ICC. Propensity score matching (PSM) (2:1) analysis was used to adjust for baseline differences. The HCC incidence between two groups was not different in the entire population (hazard ratio [HR] 0.82; 95% confidence interval [CI] 0.66–1.02, p = 0.078) and in the PSM population (HR 0.83; 95% CI 0.65–1.06, p = 0.129). Among decompensated cirrhotic patients, a lower risk of HCC was observed in TDF group than in ETV group (HR 0.54; 95% CI 0.30–0.98, p = 0.043, PSM model). There were no differences between ETV and TDF groups in the ICC incidence (HR 1.84; 95% CI 0.54–6.29, p = 0.330 in the entire population and HR 1.04; 95% CI 0.31–3.52, p = 0.954 in the PSM population, respectively). In conclusion, treatment with ETV and TDF showed a comparable long-term risk of HCC and ICC in CHB patients.

Validation of risk prediction scores for hepatocellular carcinoma in patients with chronic hepatitis B treated with entecavir or tenofovir

Several prediction scores for the early detection of hepatocellular carcinoma (HCC) are available. We validated the predictive accuracy of age, albumin, sex, liver cirrhosis (AASL), RESCUE-B, PAGE-B and modified PAGE-B (mPAGE-B) scores in chronic hepatitis B (CHB) patients treated with entecavir (ETV) or tenofovir disoproxil fumarate (TDF). Between 2007 and 2014, 3171 patients were recruited (1645, ETV; 1517, TDF). The predictive accuracy of each prediction score was assessed. The mean age of the study population (1977 men; 1194 women) was 48.8 years. Liver cirrhosis was present in 1040 (32.8%) patients. During follow-up (median, 58.2 months), 280 (8.8%) patients developed HCC; these patients were significantly older; more likely to be male; had significantly higher proportions of liver cirrhosis, hypertension and diabetes; and had significantly higher values for the four risk scores than those who did not develop HCC (all P < .05). Older age (hazard ratio [HR] = 1.048), male sex (HR = 2.142), liver cirrhosis (HR = 3.144) and prolonged prothrombin time (HR = 2.589) were independently associated with an increased risk of HCC (all P < .05), whereas a higher platelet count (HR = 0.996) was independently associated with a decreased risk of HCC (P < .05). The predictive accuracy of AASL score was the highest for 3- and 5-year HCC predictions (areas under the curve [AUCs] = 0.818 and 0.816, respectively), followed by RESCUE-B, PAGE-B and mPAGE-B scores (AUC = 0.780-0.815 and 0.769-0.814, respectively). In conclusion, four HCC prediction scores were assessed in Korean CHB patients treated with ETV or TDF. The AASL score showed the highest predictive accuracy.

High Risk of HBV Infection Among Vaccinated Polytransfused Children With Malignancy

AIM OF THE STUDY

The national Egyptian hepatitis B virus (HBV) vaccination program coverage of all infants started in 1992. The study aimed to assess immunity against HBV and occurrence of HBV breakthrough infections in vaccinated polytransfused children with malignancies.

PATIENTS AND METHODS

Eighty-nine polytransfused children with malignancies were recruited; 37 were on chemotherapy (male:female 20:17; mean age 7.7±4.0 y), and there were 52 naive patients (male:female 31:21; mean age 7.6±3.2 y). In addition, 162 age-matched and sex-matched healthy controls were recruited. Patients' sera were tested for quantitative anti-hepatitis B surface (HBs) (enzyme-linked immunoassays technique), hepatitis B surface antigen (HBsAg), total anti-hepatitis B core, and HBV-DNA (nested polymerase chain reaction for surface, core, and x-regions).

RESULTS

There was a significant lower percentage of having protective anti-HBs (10 to 100 IU/L) level among those receiving chemotherapy (13.5%) than those without (44.2%) and controls (32.1%). Twenty-one (67.7%) of those on chemotherapy were HBsAg positive compared with 10 (32.2%) of those without. Overall, 46 patients were HBV-DNA positive; 38 were c-region positive, 5 were s-region positive, 2 positive for the c-region and the s-region, and 1 tested positive for the c-region and the x-region. Of 46 patients, 20 were also positive for HBsAg (overt infection), while 26 had occult HBV infection (HBsAg-negative). Anti-HBs ≥10 IU/L co-existed among 45% of patients with overt infection and in 50% of those with occult infection. There was nonsignificant impact of receiving chemotherapy on the level of HBV-DNA.

CONCLUSIONS

Vaccinated children with malignancies, especially those under chemotherapy, are at a significant risk of HBV infection. The co-existence of anti-HBs with HBsAg and/or HBV-DNA may represent a possible residual transfusion-transmission risk with mutant HBV strains.

Comprehensive Analysis of Clinically Significant Hepatitis B Virus Mutations in Relation to Genotype, Subgenotype and Geographic Region

Hepatitis B virus (HBV) is a highly variable DNA virus due to its unique life cycle, which involves an error-prone reverse transcriptase. The high substitution rate drives the evolution of HBV by generating genetic variants upon which selection operates. HBV mutants with clinical implications have been documented worldwide, indicating the potential for spreading and developing their own epidemiology. However, the prevalence of such mutants among the different HBV genotypes and subgenotypes has not been systematically analyzed. In the current study, we performed large-scale analysis of 6,479 full-length HBV genome sequences from genotypes A-H, with the aim of gaining comprehensive insights into the relationships of relevant mutations associated with immune escape, antiviral resistance and hepatocellular carcinoma (HCC) development with HBV (sub)genotypes and geographic regions. Immune escape mutations were detected in 10.7% of the sequences, the most common being I/T126S (1.8%), G145R (1.2%), M133T (1.2%), and Q129R (1.0%). HBV genotype B showed the highest rate of escape mutations (14.7%) while genotype H had no mutations (P < 0.001). HCC-associated mutations were detected in 33.7% of the sequences, with significantly higher frequency of C1653T, T1753V and A1762T/G1764A in genotype G than C (P < 0.001). The overall frequencies of lamivudine-, telbivudine-, adefovir-, and entecavir-resistant mutants were 7.3, 7.2, 0.5, and 0.2%, respectively, while only 0.05% showed reduced susceptibility to tenofovir. In particular, the highest frequency of lamivudine-resistant mutations was observed in genotype G and the lowest frequency in genotype E (32.5 and 0.3%; P < 0.001). The prevalence of HBV mutants was also biased by geographic location, with North America identified as one of the regions with the highest rates of immune escape, antiviral resistance, and HCC-associated mutants. The collective findings were discussed in light of natural selection and the known characteristics of HBV (sub)genotypes. Our data provide relevant information on the prevalence of clinically relevant HBV mutations, which may contribute to further improvement of diagnostic procedures, immunization programs, therapeutic protocols, and disease prognosis.

Persistence of intrahepatic hepatitis B virus DNA integration in patients developing hepatocellular carcinoma after hepatitis B surface antigen seroclearance

Background/Aims

The role of hepatitis B virus (HBV) integration into the host genome in hepatocarcinogenesis following hepatitis B surface antigen (HBsAg) seroclearance remains unknown. Our study aimed to investigate and characterize HBV integration events in chronic hepatitis B (CHB) patients who developed hepatocellular carcinoma (HCC) after HBsAg seroclearance.

Methods

Using probe-based HBV capturing followed by next-generation sequencing technology, HBV integration was examined in 10 samples (seven tumors and three non-tumor tissues) from seven chronic carriers who developed HCC after HBsAg loss. Genomic locations and patterns of HBV integration were investigated.

Results

HBV integration was observed in six patients (85.7%) and eight (80.0%) of 10 tested samples. HBV integration breakpoints were detected in all of the non-tumor (3/3, 100%) and five of the seven (71.4%) tumor samples, with an average number of breakpoints of 4.00 and 2.43, respectively. Despite the lower total number of tumoral integration breakpoints, HBV integration sites in the tumors were more enriched within the genic area. In contrast, non-tumor tissues more often showed intergenic integration. Regarding functions of the affected genes, tumoral genes with HBV integration were mostly associated with carcinogenesis. At enrollment, patients who did not remain under regular HCC surveillance after HBsAg seroclearance had a large HCC, while those on regular surveillance had a small HCC.

Conclusions

The biological functions of HBV integration are almost comparable between HBsAg-positive and HBsAg-serocleared HCCs, with continuing pro-oncogenic effects of HBV integration. Thus, ongoing HCC surveillance and clinical management should continue even after HBsAg seroclearance in patients with CHB.

A multi-centre study of trends in hepatitis B virus-related hepatocellular carcinoma risk over time during long-term entecavir therapy

The risk of developing hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) is reduced by antiviral therapy. Here, we evaluated the chronological trends in HCC development risk starting in 2007, when entecavir reimbursement was first initiated in South Korea. Treatment-naïve patients with chronic hepatitis B (CHB) receiving entecavir 0.5 mg/d were stratified into three groups according to entecavir start time: early (2007-2010), middle (2011-2012) and late (2013-2014) cohorts Among 2442 patients, cumulative probabilities of developing HCC after 1, 3 and 5 years were, respectively, 1.7%, 5.1%, and 8.2% (early cohort; n = 672); 1.5%, 5.1% and 8.9% (middle cohort; n = 757); and 1.2%, 5.3% and 10.6% (late cohort; n = 1013; P > .05 between each pair). Older age, male, positive hepatitis B e antigen, liver cirrhosis, Child-Pugh class B (vs A) and lower platelet count significantly predicted HCC development in univariate analysis (P < .001), whereas entecavir start time (early vs middle vs late cohorts) did not affect the risk of HCC development (P = .457). A multivariate analysis revealed that older age (adjusted hazard ratio [aHR]=1.041), male gender (aHR = 2.069), liver cirrhosis (aHR = 3.771) and Child-Pugh class B (vs A, aHR = 1.548) were independently associated with an increased risk of HCC development, whereas higher platelet count was independently associated with a reduced risk of HCC development (aHR = 0.993; all P < .05). In conclusion, the risk of developing HCC among patients receiving entecavir in South Korea has been stable since 2007. To establish more effective HCC surveillance programs, further studies regarding the carcinogenic roles of nonviral factors are required.

The evolution and clinical impact of hepatitis B virus genome diversity

The global burden of hepatitis B virus (HBV) is enormous, with 257 million persons chronically infected, resulting in more than 880,000 deaths per year worldwide. HBV exists as nine different genotypes, which differ in disease progression, natural history and response to therapy. HBV is an ancient virus, with the latest reports greatly expanding the host range of the Hepadnaviridae (to include fish and reptiles) and casting new light on the origins and evolution of this viral family. Although there is an effective preventive vaccine, there is no cure for chronic hepatitis B, largely owing to the persistence of a viral minichromosome that is not targeted by current therapies. HBV persistence is also facilitated through aberrant host immune responses, possibly due to the diverse intra-host viral populations that can respond to host-mounted and therapeutic selection pressures. This Review summarizes current knowledge on the influence of HBV diversity on disease progression and treatment response and the potential effect on new HBV therapies in the pipeline. The mechanisms by which HBV diversity can occur both within the individual host and at a population level are also discussed.

Prognosis of Untreated Minimally Active Chronic Hepatitis B Patients in Comparison With Virological Responders by Antivirals

Serum hepatitis B virus (HBV)-DNA > 2,000 IU/mL is associated with higher risk of disease progression. However, without hepatocellular carcinoma (HCC) or cirrhosis, nucleos(t)ide analogs (NUCs) are recommended only for patients with elevated serum HBV-DNA and alanine aminotransferase ≥2 × upper normal limit.

An optimized hepatocellular carcinoma prediction model for chronic hepatitis B with well-controlled viremia

BACKGROUND AND AIMS

Hepatocellular carcinoma (HCC) risk in chronic hepatitis B (CHB) substantially decreased in the era of potent antiviral therapy. We developed an optimized HCC risk prediction model for CHB with well-controlled viremia by nucelos(t)ide analogs (NUCs).

METHOD

We analysed those who achieved virological response (VR; serum HBV-DNA < 2000 IU/mL on two consecutive assessments) by NUCs. Liver stiffness by transient elastography, ultrasonography and laboratory tests was performed at the time of confirmed VR. Patients with decompensated cirrhosis or HCC at baseline were excluded. Multivariate Cox-regression analysis was used to determine key variables to construct a novel risk-scoring model.

RESULTS

Among 1511 patients, 9.5% developed HCC. Cirrhosis on ultrasonography (adjusted HR [aHR] 2.47), age (aHR 1.04), male (aHR 1.90), platelet count <135 000/uL (aHR 1.57), albumin <4.5 g/dL (aHR 1.77) and liver stiffness ≥11 kPa (aHR 6.09) were independently associated with HCC. Using these, CAMPAS model was developed with c-index of 0.874. The predicted and observed HCC probabilities were calibrated with a reliable agreement. Such results were reproduced from internal validation and external validation among the independent cohort (n = 252). The intermediate-risk (CAMPAS model score 75 ~ 161) and high-risk (score >161) groups were more likely to develop HCC compared with the low-risk group (score ≤75) with statistical significances (HRs; 4.43 and 47.693 respectively; both P < .001).

CONCLUSION

CAMPAS model derived through comprehensive clinical evaluation of liver disease allowed the more delicate HCC prediction for CHB patients with well-controlled viremia by NUCs.

Extremely low risk of hepatocellular carcinoma development in patients with chronic hepatitis B in immune-tolerant phase

BACKGROUND

Anti-viral therapy is not indicated for patients with chronic hepatitis B (CHB) in the immune-tolerant phase.

AIMS

To investigate the cumulative incidence of phase change and hepatocellular carcinoma (HCC) and independent predictors for phase change in patients with CHB in immune-tolerant phase.

METHODS

In total, 946 patients in immune-tolerant phase, defined as hepatitis B e antigen positivity, HBV-DNA >20 000 IU/mL and alanine aminotransferase (ALT) ≤40 IU/L, between 1989 and 2017 were enrolled from eight institutes.

RESULTS

The mean age of study population (429 men and 517 women) was 36.7 years. The mean ALT and HBV-DNA levels were 24.6 IU/L and 8.50 log₁₀ IU/mL, respectively. Of the study population, 476 (50.3%) patients remained in immune-tolerant phase throughout the study period (median: 63.6 months). The cumulative incidence rates of phase change and HCC at 10 years were 70.7% and 1.7%, respectively. Multivariate analyses revealed that HBV-DNA level >10⁷  IU/mL was associated independently with a reduced risk of phase change (hazard ratio [HR] = 0.734, P = 0.008), whereas a high ALT level, above the cut-off recommended in the Korean Association for the Study of the Liver guidelines (34 IU/L for men and 30 IU/L for women), was associated independently with a greater risk of phase change (HR = 1.885, P < 0.001).

CONCLUSIONS

The criterion of HBV-DNA level > 10⁷  IU/mL may be useful to define immune-tolerant phase. In addition, an extremely low risk of HCC development was observed in patients with CHB in immune-tolerant phase.

Molecular epidemiology of hepatitis B virus genotypes in blood donors in Islamabad, Pakistan

BACKGROUND:

Hepatitis B virus (HBV) is a major causative agent of early, severe and prolonged liver infection that subsequently leads to cirrhosis of liver and hepatocellular carcinoma. The aim of this study was to evaluate the molecular epidemiology of hepatitis B virus (HBV) genotypes and comparison of serological assay performance versus polymerase chain reaction (PCR) in HBV screening.

METHODS:

Blood samples of 8517 healthy blood donors were collected during the period of January to June 2017 from Blood Bank of Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad. Samples were screened for HBsAg assay using technique of chemiluminescence immunoassay. PCR of positive samples was carried out using already reported genotype-specific primers by Naito et al. (2001). The results were confirmed by visualizing genotype bands.

RESULTS:

The study confirmed the presence of HBV in 2.5% of blood donors, and PCR confirmed the presence of HBV-DNA in 92 samples. The genotyping was done by PCR using type-specific primer sequences. PCR was dogged to check six genotypes, i.e., A, B, C, D, E, and F. The results of this study show high levels of Genotype D is this region, i.e., 52.17% with less dominating Genotype C, which is 16.30% with decreasing ratio of Genotype E (14.13%), Genotype A and B (9.78%), and mixed D + E (2.17%). The presence of coinfection is found at lowest rate. Due to the high percentage of HBV/D, it is concluded that D genotype is common in our population.

CONCLUSION:

The most prevalent HBV genotype in ICT region was genotype D, which is responsible for liver cirrhosis and hepatocellular carcinoma. Efficacy of drugs varies with variation in genotypes of hepatitis B virus and also with geographical distribution.

Validation of the CAMD Score in Patients With Chronic Hepatitis B Virus Infection Receiving Antiviral Therapy

BACKGROUND & AIMS

Researchers previously developed a scoring system to determine the risk of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B virus (HBV) infection, based on the presence of cirrhosis, patient age, male sex, and diabetes (called the CAMD scoring system). We validated the CAMD scoring system and compared its performance with that of other risk assessment models in an independent cohort.

METHODS

We followed up 3277 patients with chronic HBV infection (mean age, 48.7 y; 62.6% male; 32.4% with cirrhosis) who were treated with entecavir (n = 1725) or tenofovir (n = 1552) as the first-line antiviral agent in 4 academic teaching hospitals in the Republic of Korea. The primary outcome was development of HCC. We evaluated the ability of the CAMD, PAGE-B, and mPAGE-B scoring systems to identify patients who would develop HCC using integrated area under the curve (iAUC) analysis.

RESULTS

Over a median follow-up period of 58.2 months, 8.9% of the patients developed HCC. Patients who developed HCC were older, more likely to be male, and had higher proportions of cirrhosis and diabetes than patients who did not develop HCC (all P < .05). CAMD scores identified patients who developed HCC with an iAUC of 0.790, mPAGE-B scores with an iAUC of 0.769, and PAGE-B scores with an iAUC of 0.760. The 5-year cumulative risks of HCC were 1.3% in patients with low CAMD scores (<8), 8.0% in patients with intermediate CAMD scores (8-13), and 24.3% in patients with high CAMD scores (>13) (P < .001 for comparison of low- vs intermediate-score groups and between intermediate- vs high-score groups). The predicted and observed probabilities of HCC had excellent agreement.

CONCLUSIONS

We validated the CAMD scoring system in determining the risk of HCC in patients with chronic HBV treatment receiving entecavir or tenofovir treatment. Validation was performed in a cohort of patients in the Republic of Korea, where most patients have genotype C2 HBV infection.

Liver diseases in the Asia-Pacific region: a Lancet Gastroenterology & Hepatology Commission

The Asia-Pacific region is home to more than half of the global population and accounted for 62·6% of global deaths due to liver diseases in 2015. 54·3% of global deaths due to cirrhosis, 72·7% of global deaths due to hepatocellular carcinoma, and more than two-thirds of the global burden of acute viral hepatitis occurred in this region in 2015. Chronic hepatitis B virus (HBV) infection caused more than half of the deaths due to cirrhosis in the region, followed by alcohol consumption (20·8%), non-alcoholic fatty liver disease (NAFLD; 12·1%), and chronic infection with hepatitis C virus (HCV; 15·7%). In 2015, HBV accounted for about half the cases of hepatocellular carcinoma in the region. Preventive strategies for viral hepatitis-related liver disease include increasing access to clean drinking water and sanitation. HBV vaccination programmes for neonates have been implemented by all countries, although birth-dose coverage is extremely suboptimal in some. Availability of screening tests for blood and tissue, donor recall policies, and harm reduction strategies are in their initial stages in most countries. Many governments have put HBV and HCV drugs on their essential medicines lists and the availability of generic versions of these drugs has reduced costs. Efforts to eliminate viral hepatitis as a public health threat, together with the rapid increase in per-capita alcohol consumption in countries and the epidemic of obesity, are expected to change the spectrum of liver diseases in the Asia-Pacific region in the near future. The increasing burden of alcohol-related liver diseases can be contained through government policies to limit consumption and promote less harmful patterns of alcohol use, which are in place in some countries but need to be enforced more strictly. Steps are needed to control obesity and NAFLD, including policies to promote healthy lifestyles and regulate the food industry. Inadequate infrastructure and insufficient health-care personnel trained in liver diseases are issues that also need to be addressed in the Asia-Pacific region. The policy response of most governments to liver diseases has thus far been inadequate and poorly funded. There must be a renewed focus on prevention, early detection, timely referral, and research into the best means to introduce and improve health interventions to reduce the burden of liver diseases in the Asia-Pacific region.

Hepatocellular Carcinoma Risk Steadily Persists over Time Despite Long-Term Antiviral Therapy for Hepatitis B: A Multicenter Study

BACKGROUND

Long-term antiviral therapy (AVT) for chronic hepatitis B (CHB) reduces the risk of hepatocellular carcinoma (HCC). We assessed the temporal trends in the incidence of HCC over time during long-term AVT among Asian patients with CHB.

METHODS

Patients with CHB receiving entecavir/tenofovir (ETV/TDF) as a first-line antiviral were recruited from four academic hospitals in the Republic of Korea. We compared the incidence of HCC during and after the first 5 years of ETV/TDF treatment.

RESULTS

Among 3,156 patients, the median age was 49.6 years and males predominated (62.4%). During the follow-up, 9.0% developed HCC. The annual incidence of HCC per 100 person-years during the first 5 years (n = 1,671) and after the first 5 years (n = 1,485) was statistically similar (1.93% vs. 2.27%, P = 0.347). When the study population was stratified according to HCC prediction model, that is, modified PAGE-B score, the annual incidence of HCC was 0.11% versus 0.39% in the low-risk group (<8 points), 1.26% versus 1.82% in the intermediate-risk group (9-12 points), and 4.63% versus 5.24% in the high-risk group (≥13 points; all P > 0.05). A Poisson regression analysis indicated that the duration of AVT did not significantly affect the overall trend of the incidence of HCC (adjusted annual incidence rate ratio = 0.85; 95% confidence interval, 0.66-1.11; P = 0.232).

CONCLUSIONS

Despite long-term AVT, the risk of HCC steadily persists over time among patients with CHB in the Republic of Korea, in whom HBV genotype C2 predominates.

IMPACT

Careful HCC surveillance is still essential.

Analysis of the in vitro replication phenotype of African hepatitis B virus (HBV) genotypes and subgenotypes present in Australia identifies marked differences in DNA and protein expression

Hepatitis B virus infection in Africa is characterised by distinct genotypes with observed differences in natural history and clinical outcomes. Replication-competent cDNA clones of African genotypes were generated from patient-derived sequences identified in African children with chronic hepatitis B infection living in Australia: A1 (wild-type and basal core promotor (BCP) mutant), D2, D6, and E, comparing the replication phenotype to an established D3 cDNA clone in a transient transfection cell culture model. All clones replicated efficiently although less than the European D3 reference clone, and demonstrated marked differences in replication capacity, highest for subgenotypes A1 and D2. The BCP mutation increased the replication levels of the A1 subgenotype compared to wild-type. Intracellular and secreted surface antigen and HBeAg protein expression also varied across genotypes. We observed differences in functional activity in the upstream regulatory region across the genotypes that may contribute to the replication and protein differences observed.

Molecular epidemiology, phylogenetic analysis and genotype distribution of hepatitis B virus in Saudi Arabia: Predominance of genotype D1

Despite the implementation of various vaccination programs, hepatitis B virus (HBV) poses a considerable health problem in Saudi Arabia. Insight on HBV evolutionary history in the region is limited. We performed a comprehensive epidemiological and phylogenetic reconstruction based on a large cohort of HBV infected patients. Three hundred and nineteen HBV-infected patients with different clinical manifestations, including inactive and active chronic carriers and patients with cirrhosis and hepatocellular carcinoma (HCC), were enrolled in this study. The full-length large S gene was amplified and sequenced. Phylogenetic analysis was performed to determine the genotype and subgenotypes of the isolates. Phylogenetic tree analysis revealed that genotype D is the most dominant genotype among patients. Moreover, this analysis identified two strains with genotype E isolated from active carriers. Detailed phylogenetic analyses confirmed the presence of four HBV D subgenotypes, D1 (93%, n = 296), D2 (0.02%, n = 5), D3 (0.003%, n = 1), and D4 (0.003%, n = 1). In addition, six genotype D strains were not assigned to any existing HBV D subgenotype. The large S gene of eight strains showed signatures of genotype recombination between the genotypes D and A and between D and E. Several strains harbored medically important point mutations at the protein level. Along with the dominance of the HBV genotype D, isolation of the E genotype and several recombinant strains from patients with Saudi Arabian origin is an essential result for decisions involving therapeutic measures for patients. Development of vaccines and detection of diagnostic escape mutations at antigenic epitopes on the HBsAg will be valuable to public health authorities. Furthermore, the diversity at the nucleotide and amino acid levels and different proportions of dN/dS at the PreS1, PreS2, and HBsAg reveal the selective pressure trend from inactive status towards advanced liver diseases.

Prevalence of Hepatitis B Virus Infection in Shenzhen, China, 2015-2018

China has nearly 10% of the general HBV carrier population in the world; this infection is the most common cause of chronic liver disease. Understanding HBV epidemiology is essential for future infection control, evaluation, and treatment. This study determined the prevalence of HBV infection in Shenzhen by serological testing and analysis in 282,166 HBV screening cases for the following: HBcAb, indicative of previous HBV infection; HBsAg, indicative of chronic (current) infection; HBsAb, indicative of immunity from vaccination; and 34,368 HBV etiological screening cases for HBV-DNA, indicative of virus carriage, in which 1,204 cases were genotyped and mutation analyzed for drug-resistance evaluation. Shenzhen was a highly endemic area of HBV throughout the study period (prevalence 9.69%). HBV infections were almost entirely in the 20 and older age groups with a male-to-female ratio of 1.16:1 which is approximately the same as the male-to-female ratio of the general population in China. However, only 71.25% of the general population retained HBV immune protection. Genotype B and C were identified as the most common agents; recombinant B/C and B/D also existed; some cases, however, could not be genotyped. NAs resistant mutation occurrence patterns were multitudinous; single mutation patterns of rtM204I/V and rtL180M occurrences accounted for majority, followed by the combinational mutation pattern L180M + M204I/V. Drug-resistance was prevalent, mainly occurring in the cross resistance patterns LAM + LdT and LAM + LdT + ETV, and significantly more critical in males. These results demonstrate that all people free from HBV infection should obtain injections of the vaccine or booster shots, and conventional virologic detection in a clinical laboratory center should incorporate genotype and mutation alongside the serological factors for etiology and develop better classification methods, such as sequencing.

External validation of the modified PAGE-B score in Asian chronic hepatitis B patients receiving antiviral therapy

BACKGROUND AND AIMS

The modified PAGE-B (mPAGE-B) score comprising age, gender, platelet count and albumin was recently proposed to predict hepatocellular carcinoma (HCC) risk among chronic hepatitis B (CHB) patients undergoing antivirals. Here, in the independent cohort, we externally validated the predictive performance of the mPAGE-B score and compared it with those of conventional HCC prediction models.

METHODS

We consecutively recruited CHB patients treated with lamivudine, entecavir or tenofovir as the first-line antiviral regimen. Patients with decompensated cirrhosis or HCC at baseline were excluded. Predictive performances of the mPAGE-B score and other models were assessed with comparison.

RESULTS

Among 1330 patients, 9.6% developed HCC during follow-up. The mPAGE-B score provided the highest Harrell's c-index (0.769), followed by the GAG-HCC (0.751), PAGE (0.744), REACH-B (0.686) and CU-HCC (0.618) scores. The mPAGE-B score showed the similar performance to the PAGE-B and GAG-HCC scores and the better performance than the REACH-B and CU-HCC scores. Cumulative HCC probabilities at 5- and 7-years were 0.0% and 0.0% in low-risk group (mPAGE-B score ≤ 8), 6.1% and 10.8% in intermediate-risk group (mPAGE-B score 9-12) and 18.7% and 26.7% in high-risk group (mPAGE-B score ≥ 13) respectively (both P < 0.001 between adjacent two groups). C-indices of the mPAGE-B score were 0.785 and 0.724 among subgroups treated with entecavir or tenofovir (n = 1011) and with lamivudine (n = 319), respectively, which are overall similar to those of the PAGE-B score.

CONCLUSION

The mPAGE-B score showed acceptable predictive performances. Compared to the PAGE-B score, addition of albumin as a constituent provided the marginal benefit.

A multicenter study of entecavir vs. tenofovir on prognosis of treatment-naïve chronic hepatitis B in South Korea

BACKGROUND & AIMS

It is currently unclear which antiviral agent, entecavir (ETV) or tenofovir disoproxil fumarate (TDF), is superior for improving prognosis in patients with chronic hepatitis B (CHB). Here, we assessed the ability of these 2 antivirals to prevent liver-disease progression in treatment-naïve patients with CHB.

METHODS

From 2012 to 2014, treatment-naïve patients with CHB who received ETV or TDF as a first-line antiviral agent were recruited from 4 academic teaching hospitals. Patients with decompensated cirrhosis or hepatocellular carcinoma (HCC) at enrollment were excluded. Cumulative probabilities of HCC and death or orthotopic liver transplant (OLT) were assessed.

RESULTS

In total, 2,897 patients (1,484 and 1,413 in the ETV and TDF groups, respectively) were recruited. The annual HCC incidence was not statistically different between the ETV and TDF groups (1.92 vs. 1.69 per 100 person-years [PY], respectively; adjusted hazard ratio [HR] 0.975 [p = 0.852] by multivariate analysis). Propensity score (PS)-matched and inverse probability of treatment weighting (ITPW) analyses yielded similar patterns of results (HR 1.021 [p = 0.884] and 0.998 [p = 0.988], respectively). The annual incidence of death or OLT was not statistically different between the ETV and TDF groups (0.52 vs. 0.53 per 100 PY, respectively; adjusted HR 1.202 [p = 0.451]). PS-matched and ITPW analyses yielded similar patterns of results (HR 1.248 [p = 0.385] and 1.239 [p = 0.360], respectively). These findings were consistently reproduced in patients with compensated cirrhosis (all p >0.05).

CONCLUSIONS

The overall prognosis in terms of HCC and death or OLT was not statistically different between the ETV and TDF groups. Further studies are needed to validate our results.

LAY SUMMARY

It is currently unclear which antiviral agent, entecavir or tenofovir disoproxil fumarate, is superior for improving prognosis in patients with chronic hepatitis B virus infection. In this analysis we found that there was no difference in terms of overall prognosis, including risk of hepatocellular carcinoma, death, or the need for a liver transplant, in patients receiving either antiviral.

Efficacy and Safety of Besifovir Dipivoxil Maleate Compared With Tenofovir Disoproxil Fumarate in Treatment of Chronic Hepatitis B Virus Infection

BACKGROUND & AIMS

Besifovir dipivoxil maleate (BSV) has activity against hepatitis B virus (HBV). We performed a phase 3 study to compare the antiviral efficacy and safety of BSV vs tenofovir disoproxil fumarate (TDF) in patients with chronic HBV infection in Korea.

METHODS

We conducted a double-blind, non-inferiority trial of 197 patients with chronic HBV infection at 22 sites in South Korea, from November 2013 through February 2016. Patients were randomly assigned to groups given BSV (150 mg, n = 99) or TDF (300 mg, n = 98) for 48 weeks. We evaluated virologic responses to therapy (HBV DNA <69 IU/mL or 400 copies/ml), bone mineral density (BMD), and renal outcomes for safety analysis. The main efficacy endpoint was the proportion of patients with a virologic response at week 48. After 48 weeks, TDF was switched to BSV (150 mg) for an additional 48 weeks.

RESULTS

After 48 weeks of treatment, 80.9% of patients given BSV and 84.9% of patients given TDF met the efficacy endpoint, indicating the non-inferiority of BSV to TDF. At week 96, 87.2% of patients in the BSV-BSV and 85.7% of patients in the TDF-BSV had a virologic response. At week 48, changes in hip and spine BMD differed significantly between the BSV and TDF groups, whereas the estimated glomerular filtration rate in the TDF group was significantly lower than that in the BSV group. However, at 96 weeks, there were no significant differences in BMD and estimated glomerular filtration rate between the BSV-BSV and TDF-BSV groups.

CONCLUSIONS

BSV has antiviral efficacy comparable to that of TDF after 48 weeks of treatment, with durable effects for 96 weeks. BSV has a better safety profile than TDF, in terms of bone and renal outcomes. ClinicalTrials.gov no: NCT01937806.

rt269I Type of Hepatitis B Virus (HBV) Leads to HBV e Antigen Negative Infections and Liver Disease Progression via Mitochondrial Stress Mediated Type I Interferon Production in Chronic Patients With Genotype C Infections

Hepatitis B virus infection is a serious global health problem and causes life-threatening liver disease. In particular, genotype C shows high prevalence and severe liver disease compared with other genotypes. However, the underlying mechanisms regarding virological traits still remain unclear. This study investigated the clinical factors and capacity to modulate Type I interferon (IFN-I) between two HBV polymerase polymorphisms rt269L and rt269I in genotype C. This report compared clinical factors between rt269L and rt269I in 220 Korean chronic patients with genotype C infections. The prevalence of preC mutations between rt269L and rt269I was compared using this study's cohort and the GenBank database. For in vitro and in vivo experiments, transient transfection using HBV genome plasmid and HBV virion infection using HepG2-hNTCP-C4 and HepaRG systems and hydrodynamic injection of HBV genome into mice tails were conducted, respectively. This report's clinical data indicated that rt269I vs. rt269L was more significantly related to HBV e antigen (HBeAg) negative serostatus, lower levels of HBV DNA and HBsAg, and disease progression. Our epidemiological study showed HBeAg negative infections of rt269I infections were attributed to a higher frequency of preC mutations at 1896 (G to A). Our in vitro and in vivo studies also found that rt269I could lead to mitochondrial stress mediated STING dependent IFN-I production, resulting in decreasing HBV replication via the induction of heme-oxygenase-1. In addition, we also found that rt269I could lead to enhanced iNOS mediated NO production in an IFN-I dependent manner. These data demonstrated that rt269I can contribute to HBeAg negative infections and liver disease progression in chronic patients with genotype C infections via mitochondrial stress mediated IFN-I production.

Genomic analysis of Hepatitis B virus and its association with disease manifestations in Bangladesh

The direct cytopathic effects of the hepatitis B virus (HBV) on subsequent liver damage are not fully understood in HBV-infected patients. However, associations between the prevalence of various HBV genotypes and the extent of liver damage have been reported from different parts of the world. The purpose of this study was to determine the distribution of HBV genotypes in patients with chronic HBV infection in Bangladesh, a country of 160 million people, of which approximately 3–6 million are chronically infected HBV patients. In addition, whole and partial genome sequencing of HBV was performed to evaluate the relationship between HBV mutations and genotypes. We found that 42% of the patients with low HBV DNA and normal levels of alanine aminotransferase (ALT) had HBV genotype D. In contrast, the HBV genotype C was dominant among patients with high HBV DNA levels (>2000 IU/ml) and elevated ALT and in patients with liver cirrhosis (LC) and hepatocellular carcinomas (HCC). Whole and partial genome sequences of HBV revealed that most patients with LC and HCC had HBV genotype C with mutations at the T1762/A1764 positions. It seems that Bangladesh represents a borderline country, situated within East Asia, which mainly consists of individuals with HBV genotypes B and C, whereas in the western parts of Asia, HBV genotypes A and D are prevalent. Bangladesh is, therefore, an excellent model for the comparison of the pathophysiology of three major HBV genotypes in a single population. The findings of this study suggest a possible association between HBV viral factors and the extent of liver damage in chronic HBV-infected patients.