Distribution of hepatitis B virus genotypes in Korea

Predictive value of HBeAg titer dynamics for HBsAg clearance in pediatric chronic hepatitis B

Introduction

Achieving functional cure of chronic hepatitis B (CHB), characterized by the loss of HBV DNA and HBsAg, remains challenging in adults but demonstrates higher success rates in children. Elucidating the factors influencing HBsAg loss in pediatric patients is crucial for optimizing treatment strategies. This study aimed to evaluate the predictive value of HBeAg titer dynamics for HBsAg clearance in pediatric CHB and develop a predictive model incorporating these dynamics.

Material and methods

This retrospective cohort study analyzed 119 children aged 1-18 years with CHB treated with nucleos(t)ide analogues. Patient outcomes were evaluated using two independent classification approaches: HBsAg loss status and age stratification (≤6 vs. >6 years). Treatment response was assessed through longitudinal HBeAg titer measurements during the first 12 months. Based on identified predictors, a logistic regression model was developed incorporating age and HBeAg titer dynamics to predict HBsAg clearance probability.

Results

The study population exhibited a median age of 6.2 years. Factors associated with HBsAg loss encompassed younger age, female sex, and absence of breakthrough. In multivariate analysis, younger age was identified as the only significant factor. The cumulative HBsAg loss rate demonstrated markedly higher values in the ≤6 years group (Hazard ratio 7.69). HBeAg titer decline exhibited significantly steeper trajectories in the HBsAg loss group. The developed predictive model, "Log Odds = -1.182 + 0.308 × log_reduction-0.205 × age", demonstrated good performance with high accuracy.

Conclusions

Early HBeAg titer dynamics combined with age at treatment initiation may serve as useful predictors of HBsAg clearance in pediatric CHB. Our predictive model, utilizing readily available semi-quantitative HBeAg measurements, could potentially assist clinicians in therapeutic decision-making and individualized treatment strategies.

Hepatitis B virus immunity prior to and after administration of a ‘booster’ dose of vaccine among health-care students at a South African university

Background

Health-care students (HCSs) are at risk of occupational exposure to hepatitis B virus (HBV) infection despite an effective hepatitis B vaccine (HepB) being available. The majority of current HCSs are born after HepB was introduced into the South African Expanded Programme on Immunisation in 1995. Thus, it is assumed that having received HepB in infancy, a single 'booster' dose would suffice. This study aimed to investigate HBV immunity prior to and after administration of a HepB 'booster' dose.

Methods

Hepatitis B surface antibody (anti-HBs) levels were determined in first year HCSs at the University of the Witwatersrand, before and after receiving the 'booster'. Participant demographics and HepB history were captured using a structured questionnaire.

Results

Before receiving the 'booster', 56% (101/180) had anti-HBs < 10 mIU/mL and were non-immune. A further 35% had anti-HBs levels of 10 - 99 mIU/mL, and 9% had ≥100 mIU/mL. <30% of HCSs self-reported completion of a three-dose primary series, which was significantly associated with higher baseline anti-HBs levels compared to those with a partial schedule (p = 0.045). Following vaccination, 39% (71/180) returned for follow-up with a significant median (IQR) increase of 476 (151 - 966) mIU/mL (p < 0.001). Of the 45 students who had non-immune baseline levels, 73% (33/45) responded with ≥100 mIU/mL, 16% (7/45) with 10 - 99 mIU/mL and 11% (5/45) remained non-immune. Levels of ≥100 mIU/mL were achieved by 100% of students with baseline levels ≥10 mIU/mL (n = 26).

Conclusion

More than half of the HCSs were not immune to HBV prior to receiving the recommended 'booster' vaccine. Following vaccination, 7% (5/71) remained unprotected. This study highlights that in the absence of vaccination records and without confirming the immune status of HCSs, it cannot be assumed that HCSs will be protected following a 'booster'. Policy reform and inclusion of serological tests for immunity prior to HCSs initiating clinical exposure are recommended.

Global prevalence and molecular characteristics of three clades within hepatitis B virus subgenotype C2: Predominance of the C2(3) clade in South Korea

Hepatitis B Virus (HBV) genotypes reflect geographic, ethical or clinical traits and are currently divided into 10 genotypes (A-J). Of these, genotype C is mainly distributed in Asia, is the largest group and comprises more than seven subgenotypes (C1-C7). Subgenotype C2 is divided into three phylogenetically distinct clades, C2(1), C2(2), and C2(3), and is responsible for most genotype C infections in three East Asian nations, including China, Japan, and South Korea, which are major HBV endemic areas. However, despite the significance of subgenotype C2 with regard to clinical or epidemiologic aspects, its global distribution and molecular characteristics remain largely unknown. Here, we analyze the global prevalence and molecular characteristics between 3 clades within subgenotype C2 using 1,315 full genome sequences of HBV genotype C retrieved from public databases. Our data show that almost all HBV strains from South Korean patients infected with genotype C belong to clade C2(3) within subgenotype C2 [96.3%] but that HBV strains from Chinese or Japanese patients belong to diverse subgenotypes or clades within genotype C, suggesting clonal expansion of a specific HBV type, C2(3), among the Korean population. Our genome sequence analysis indicated a total of 21 signature sequences specific to the respective clades C2(1), C2(2), and C2(3). Of note, two types of four nonsynonymous C2(3) signature sequences, sV184A in HBsAg and xT36P in the X region, were detected in 78.9 and 82.9% of HBV C2(3) strains, respectively. In particular, HBV strains C2(3) versus C2(1) and C2(2) show a higher frequency of reverse transcriptase mutations related to nucleot(s)ide analog (NA) resistance, including rtM204I and rtL180M, suggesting an increased possibility of C2(3) infection in those with NA treatment failure. In conclusion, our data show that HBV subgenotype C2(3) is extremely prevalent in Korean patients with chronic HBV infection, which is distinct from two other East Asian nations, China and Japan, where diverse subgenotypes or clades within genotype C coexist. This epidemiologic trait might affect distinct virological and clinical traits in chronic HBV patients in Korea, where exclusively C2(3) infection is predominant.

Lack of geographical and ethnic distribution of Hepatitis B virus genotypes in Hainan Island, China

Recent studies showed that the distribution of hepatitis B virus (HBV) genotype exhibited geographical and ethnic characteristics. Haikou city is the largest city on Hainan Island that geographically isolated from mainland of China, and is the home of multiple ethnic groups. The aim of the study was to investigate the characteristics of the HBV genotype/subgenotype distribution in Haikou city. HBV DNA was isolated from180 serum samples derived from the Han and Li groups. The HBV genotype was detected by polymerase chain reaction using genotype-specific primers and was further determined by full-length genome sequences. The results revealed that the genotype B (37.2%) and C (62.8%) were the predominant HBV genotypes in Haikou, regardless of ethnic background., Additionally, the genotype distribution was not significantly different regarding ethnicity, sex or level of serum HBV DNA. Moreover, there were multiple subgenotypes circulating in the region. In conclusion, our study revealed the diverse HBV genotypes/subgenotypes in Haikou. These findings provide a preliminary study of the distribution of HBV genotypes circulating on Hainan Island.

Baseline and on-treatment HBcrAg levels as predictors of HBeAg seroconversion in chronic hepatitis B patients treated with antivirals

HBeAg seroconversion is an important treatment endpoint. We aimed to identify predictors of seroconversion using serum HBsAg and hepatitis B core-related antigen (HBcrAg) in HBeAg-positive patients treated with nucleos(t)ide analogs (NAs). Data and samples from 70 HBeAg-positive patients treated with entecavir or tenofovir between January 2007 and December 2017 were retrospectively analysed. The mean follow-up period was 11 years. The predictive power for HBeAg seroconversion of HBcrAg levels at baseline and 2 years after antiviral therapy was determined using receiver operating curve analysis. Twenty-one patients (30%) achieved HBeAg seroconversion at a mean of 28 (range, 12-84) months after antiviral treatment. The median baseline HBcrAg and HBsAg levels were 6.9(5.7-7.0) vs. 5.8(5.5-6.5) log10 U/mL (p = .006), 4.9(4.5-5.1) vs. 4.5(4.1-5.0) log10 IU/mL (p = .044) in the no seroconversion group and seroconversion group, respectively. In the multivariate analysis, the serum HBcrAg levels at baseline and 2 years after antiviral therapy were predictive factors for HBeAg seroconversion ([HR]; 0.326; [CI], 0.111-0.958; p = .042 and HR, 0.4555; CI, 0.211-0.984; p = .045). HBcrAg levels≤6.5log10 U/mL at baseline and ≤5.3log10 U/mL at 2 years after antiviral therapy had sensitivities of 53.1% and 69.8%, specificities of 95.2% and 70.6%, positive predictive values of 82.6% and 50.0%, and negative predictive values of 82.6% and 84.5%, respectively, with AUROCs of 0.712 (95%CI, 0.596-0.830) and 0.745 (95%CI, 0.599-0.891) for predicting HBeAg seroconversion. In chronic hepatitis B patients treated with NAs, HBcrAg levels≤6.5log10 U/mL at baseline and ≤5.3log10 U/mL at 2 years after antiviral therapy were useful predictive factors of HBeAg seroconversion.

Hepatitis B virus genotypes in Brazil: Introduction and dissemination

Hepatitis B is a viral infectious disease highly spread worldwide with a long evolutionary history associated with human migrations through the continents and countries. Hepatitis B virus (HBV) was disseminated probably from Africa and diverged into ten genotypes (HBV-A to HBV-J) distributed around the world. In Brazil, almost all HBV genotypes were already reported, with a predominance of three ones: A (52.1%), D (36.8%), and F (7.7%). This review aimed to evaluate the introduction and dissemination of the main HBV genotypes and subgenotypes in Brazil over the last centuries to explain the current epidemic scenario. The highest frequency of HBV-A is a consequence of the introduction and spreading of HBV-A1 in the 16th to 19th centuries due to the African slave trade, but the more recent introduction of HBV-A2 from Europe also contributed to the current situation. HBV-D is the second most frequent genotype because it was consecutively introduced by migrations from Europe (mainly subgenotype D3, but also D2) and the Middle East (D1) in the 19th to 20th centuries. On contrary, HBV-F (F1a, F1b, F2a, F2b, F3, and F4) was disseminated by the Amerindians in all South American countries, including Brazil, by migrations inside the continent for more than three centuries ago. Other HBV genotypes are rare and eventually frequent in some human groups because of the dissemination by very specific epidemiological routes. In conclusion, the current scenario of the HBV epidemics is a consequence of the introduction and dissemination of some subgenotypes from the three main genotypes A, D, and F over the last five centuries.

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.

GWAS identifying HLA-DPB1 gene variants associated with responsiveness to hepatitis B virus vaccination in Koreans: Independent association of HLA-DPB1*04:02 possessing rs1042169 G - rs9277355 C - rs9277356 A

Recently, HLA class II loci, including HLA-DPB1, have been reported to be associated with interindividual variance in the hepatitis B (HB) vaccine response. In this study, we investigated significant single nucleotide polymorphisms (SNPs) for anti-HBs antibody levels in 6867 healthy Koreans using a genome-wide association study (GWAS). In GWAS, the top 20 SNPs that showed significant association with anti-HBs levels (P < 1.0 × 10^-29 ) all resided in HLA-DPB1. Utilizing PCR sequencing, we verified the relationship of the top 3 most significant SNPs (rs1042169, rs9277355 and rs9277356) from the GWAS and genotypes of HLA-DPB1 with the HB vaccine response in Korean infants who received a scheduled vaccination. The DPB1*04:02 allele has G, C and A nucleotides for the 3SNP sites, and was significantly more frequent in responders than in nonresponders (10.9% vs 1.0%, P_c  = 0.018). DPB1*05:01 was significantly more frequent in nonresponders than in responders (49.0% vs 31.1%, P_c  = 0.018). In multivariate logistic regression, DPB1*04:02 showed a significant association with both vaccine response (P = 0.037, OR = 8.465) and high-titre response (P = 0.027, OR = 9.860). The haplotypes rs1042169 G - rs9277355 C - rs9277356 A showed a significant association with a high-titre response only (P = 0.002, OR = 2.941). In conclusion, DPB1*04:02 possessing rs1042169 G - rs9277355 C - rs9277356 A is an independent predictor of the HB vaccine response in Koreans.

Prediction model for hepatocellular carcinoma risk in treatment-naive chronic hepatitis B patients receiving entecavir/tenofovir

BACKGROUND/AIM

Accurate assessment of hepatocellular carcinoma (HCC) risk in chronic hepatitis B (CHB) patients receiving entecavir (ETV)/tenofovir disoproxil fumarate (TDF) is likely to play a pivotal role in post-treatment follow-up strategy. We aimed to develop a simple and reliable predictive model for HCC risk in these patients.

PATIENTS AND METHODS

A database of 1242 consecutive treatment-naive CHB patients who initially underwent ETV/TDF between February 2007 and January 2017 at four referral hospitals in South Korea was analyzed. The HCC risk model was constructed on the basis of a multivariable Cox proportional hazards model in the derivation dataset (n=944) and was validated using Harrell's C-statistic in a validation dataset (n=298).

RESULTS

The 3/5-year cumulative incidence rates of HCC were 3.9/6.5 and 4.2/11.6% in the derivation and the validation dataset, respectively (P=0.08). In the derivation dataset, we identified four factors associated with HCC, namely, age, albumin, sex, and liver cirrhosis. The AASL (age, albumin, sex, liver cirrhosis)-HCC scoring system was developed on the basis of these factors, and simplified to an integer scoring system. AASL-HCC scores were found to have high discriminating performance for the prediction of HCC development at 5 years in the derivation (C-statistics=0.802, 95% confidence interval: 0.716-0.888) and validation dataset (C-statistics=0.805, 95% confidence interval: 0.671-0.939). When AASL-HCC scores were classified as 5 or less, 6-19, and at least 20 (low-risk, intermediate-risk, and high-risk groups, respectively), the 5-year cumulative incidence rates of HCC were 0, 4.2, and 17.6%, respectively, in the derivation dataset.

CONCLUSIONS

The AASL-HCC model was simple and reliable for HCC risk prediction in treatment-naive CHB patients receiving ETV/TDF, and is easily applicable in the clinical setting.

Origin and dissemination of hepatitis B virus genotype C in East Asia revealed by phylodynamic analysis and historical correlates

Hepatitis B virus disease progression in East Asia is most frequently associated with genotype C (HBV/C). The increasing availability of HBV/C genetic sequences and detailed annotations provides an opportunity to investigate the epidemiological factors underlying its evolutionary history. In this study, the Bayesian phylogeography framework was used to investigate the origins and patterns in spatial dissemination of HBV/C by analyzing East Asian sequences obtained from 1992 to 2010. The most recent common ancestor of HBV/C was traced back to the early 1900s in China, where it eventually diverged into two major lineages during the 1930s-1960s that gave rise to distinct epidemic waves spreading exponentially to other East Asian countries and the USA. Demographic inference of viral effective population size over time indicated similar dynamics for both lineages, characterized by exponential growth since the early 1980s, followed by a significant bottleneck in 2003 and another increase after 2004. Although additional factors cannot be ruled out, we provide evidence to suggest this bottleneck was the result of limited human movement from/to China during the SARS outbreak in 2003. This is the first extensive evolutionary study of HBV/C in East Asia as well as the first to assess more realistic spatial ecological influences between co-circulating infectious diseases.

Performance Evaluation of the Beckman Coulter DxN VERIS Hepatitis B Virus (HBV) Assay in Comparison With the Abbott RealTime HBV Assay

The detection and quantification of hepatitis B virus (HBV) DNA plays an important role in diagnosing and monitoring HBV infection as well as in assessing the therapeutic response. We compared the analytical performance of a random access, fully automated HBV assay—DxN VERIS Molecular Diagnostics System (Beckman Coulter, Brea, CA, USA)—with that of Abbott RealTime HBV assay (Abbott Laboratories, Des Plaines, IL, USA). The between-day precision of the VERIS assay ranged from 0.92% (mean 4.68 log IU/mL) to 4.15% (mean 2.09 log IU/mL) for pooled sera from HBV patients. HBV DNA levels measured by the VERIS HBV assay correlated with the calculated HBV DNA levels (r²=0.9994; P<0.0001). The lower limit of quantification was estimated as 8.76 IU/mL (Probit analysis, 95% confidence interval: 7.32–12.00 IU/mL). Passing-Bablok regression analysis showed good concordance between the VERIS and RealTime assays for 187 chronic HBV samples (y=−0.2397+0.9712x; r=0.981), as well as for 20 drug-resistant HBV genotype C positive samples (y=−0.5415+0.9954x; r=0.961). The VERIS assay demonstrated performance similar to the RealTime assay and is suitable for high-throughput HBV DNA monitoring in large hospital laboratories.

Remaining hepatocellular carcinoma risk in chronic hepatitis B patients receiving entecavir/tenofovir in South Korea

AIM

We aimed to identify the incidence rate of hepatocellular carcinoma (HCC) in chronic hepatitis B (CHB) patients treated with entecavir or tenofovir in South Korea, and to identify predictors of HCC development in these patients.

METHODS

Between January 2007 and December 2015, 582 CHB patients initially received entecavir (n = 406, 69.8%) or tenofovir (n = 176, 30.2%) for CHB.

RESULTS

During a median follow-up of 57.1 months, HCC developed in 38 (6.5%) of the 582 patients, regardless of antiviral agent type. Entecavir- and tenofovir-treated patients had similar HCC development rates (P = 0.471). For the 582 patients, 2-, 4-, and 6-year cumulative HCC development rates were 2.6%, 4.4%, and 8.3%, respectively, and the 2-, 4-, and 6-year cumulative HCC development rates of patients with liver cirrhosis were significantly greater than those of patients without liver cirrhosis (6.2%, 9.8%, and 18.4% vs. 0.3%, 1.1%, and 2.2%, respectively; P < 0.001). Older (≥60 years) patients, regardless of the presence of cirrhosis, and cirrhotic patients aged ≥40 years showed significantly higher risk of HCC development compared to others (both P < 0.05). Multivariate analysis showed that an older age (≥50 years; hazard ratio [HR] 5.02, P = 0.009), and the presence of cirrhosis (HR 4.95, P = 0.002) independently predicted HCC development.

CONCLUSIONS

The 6-year cumulative HCC development rate was 6.5% in CHB patients treated with entecavir or tenofovir. Age ≥50 years and liver cirrhosis were found to predict HCC development in these patients.

Efficacy of Pegylated Interferon Monotherapy versus Sequential Therapy of Entecavir and Pegylated Interferon in Hepatitis B e Antigen-Positive Hepatitis B Patients: A Randomized, Multicenter, Phase IIIb Open-Label Study (POTENT Study)

BACKGROUND

Until now, various types of combined therapy with nucleotide analogs and pegylated interferon (Peg-INF) in patients with hepatitis B patients have been tried. However, studies regarding the benefits of de novo combination, late-add on, and sequential treatment are very limited. The objective of the current study was to identify the efficacy of sequential treatment of Peg-INF after short-term antiviral treatment.

METHODS

Between June 2010 and June 2015, hepatitis B e antigen (HBeAg)-positive patients (n = 162) received Peg-IFN for 48 weeks (mono-treatment group, n = 81) and entecavir (ETV) for 12 weeks with a 48-week course of Peg-IFN starting at week 5 of ETV therapy (sequential treatment group, n = 81). The primary endpoint was HBeAg seroconversion at the end of follow-up period after the 24-week treatment. The primary endpoint was analyzed using Chi-square test, Fisher's exact test, and regression analysis.

RESULTS

HBeAg seroconversion rate (18.2% vs. 18.2%, t = 0.03, P = 1.000) and seroclearance rate (19.7% vs. 19.7%, t = 0.03, P = 1.000) were same in both mono-treatment and sequential treatment groups. The rate of alanine aminotransferase (ALT) normalization (45.5% vs. 54.5%, t = 1.12, P = 0.296) and serum hepatitis B virus (HBV)-DNA <2000 U/L (28.8% vs. 28.8%, t = 0.10, P = 1.000) was not different in sequential and mono-treatment groups at 24 weeks of Peg-INF. Viral response rate (HBeAg seroconversion and serum HBV-DNA <2000 U/L) was not different in the two groups (12.1% vs. 16.7%, t = 1.83, P = 0.457). Baseline HBV-DNA level (7 log10U/ml vs. 7.5 log10U/ml, t = 1.70, P = 0.019) and hepatitis B surface antigen titer (3.6 log10U/ml vs. 4.0 log10U/ml, t = 2.19, P = 0.020) were lower and predictors of responder in mono-treatment and sequential treatment groups, respectively.

CONCLUSIONS

The current study shows no differences in HBeAg seroconversion rate, ALT normalization, and HBV-DNA levels between mono-therapy and sequential therapy regimens.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT01220596; https://clinicaltrials.gov/ct2/show/NCT01220596?term=NCT01220596&rank=1.

Expression of Hepatocyte Hepatitis B Core Antigen and Hepatitis B Surface Antigen as a Marker in the Management of Chronic Hepatitis B Patients

Background/Aims

We aimed to clarify the association of hepatitis B surface antigen (HBsAg)/hepatitis B core antigen (HBcAg) with the disease status and treatment response in patients with chronic hepatitis B (CHB).

Methods

We investigated 171 biopsy-proven entecavir-treated CHB patients (109 hepatitis B e antigen [HBeAg]-positive, 62 HBeAg-negative). HBcAg expression was positive when ≥10% of hepatocytes stained, and classified into nuclear, mixed, and cytoplasmic patterns. HBsAg expressions were intracytoplasmic (diffuse, globular, and submembranous) and membranous. The histologic activity index (HAI) and fibrosis stage followed Ishak system.

Results

In HBeAg-positive patients, older age, increased HAI score, advanced fibrosis, and reduced viral load were observed when HBcAg expression shifted from nucleus to cytoplasm in HBcAg-positive patients, and HBsAg expression from non-submembranous to submembranous in HBcAg-negative patients (all, p<0.05). In HBeAg-negative patients, only intracytoplasmic HBsAg expression patterns had clinical relevance with decreased ALT levels and viremia. In HBeAg-positive patients without favorable predictors of virologic response, negative HBcAg and membranous HBsAg expression predicted greater virologic response (both, p<0.05). The probability of HBeAg seroclearance was higher in patients with increased HAI or lacking HBcAg expression (both, p<0.05). Higher serum HBsAg levels and hepatocyte HBcAg positivity were associated with reduced serum HBsAg during first and post-first year treatment, respectively (both, p<0.05).

Conclusions

Hepatocyte HBcAg/HBsAg expression is a good marker for disease status and predicting treatment response.

Risk score model for the development of hepatocellular carcinoma in treatment-naïve patients receiving oral antiviral treatment for chronic hepatitis B

Background/Aims

This study aimed to develop and validate a risk prediction model for the development of hepatocellular carcinoma (HCC) in treatment-naïve patients receiving oral antiviral treatment for chronic hepatitis B (CHB).

Methods

We investigated 2,061 Korean treatment-naïve patients with CHB treated with entecavir as an initial therapy. A risk score model for HCC development was developed based on multivariable Cox regression model in a single center (n=990) and was validated using the time-dependent area under the receiver operating characteristic curve (AUROC) in three other centers (n=1,071). The difference of HCC development among risk groups (low, intermediate, and high) categorized by risk score was also investigated.

Results

The cumulative incidence rates of HCC at 5 years were 11.2% and 8.9% in the testing and validation cohorts, respectively. HCC-Risk Estimating Score in CHB patients Under Entecavir (HCC-RESCUE) is formulated as (age+15×gender [female=0 / male=1]+23×cirrhosis [absence=0 / presence=1]). The AUROCs at 1 year, 3 years, and 5 years were 0.82, 0.81, and 0.81, respectively, in the validation cohort. A significant difference of HCC development in each risk group was determined by the 5-year HCC risk score in the validation cohort (low risk group, 2.1%; intermediate risk group, 9.3%; high risk group, 41.2%, p<0.001).

Conclusions

The study presents a new risk score model with a good ability to predict HCC development and determine high risk patients for HCC development consisting of readily available clinical factors in treatment-naïve CHB patients receiving entecavir.

Antiviral response is not sustained after cessation of lamivudine treatment in chronic hepatitis B patients: A 10-year follow-up study

Although the ideal end point for antiviral treatment in patients with chronic hepatitis B (CHB) is loss of HBsAg, the typical clinical end points are HBeAg seroconversion in HBeAg-positive patients and long-term DNA suppression in HBeAg-negative patients. We evaluated the long-term antiviral response after cessation of lamivudine treatment in CHB patients. A total of 157 patients who had discontinued lamivudine between 1997 and 2014 were enrolled (97 HBeAg-positive and 60 HBeAg-negative CHB patients). The long-term durability of the antiviral response (viralogical relapse; HBV DNA ≥10⁴  copies/ml) and the clinical course of these patients were analyzed retrospectively. In HBeAg-positive patients, the mean follow-up period after discontinuation was 72.3 months. The cumulative probabilities of virological relapse at 1, 12, 24, 48, 60, 96, and 120 months were 10.3%, 40.2%, 55.6%, 62.8%, 65.9%, 67.0%, and 67.0%, respectively. In HBeAg-negative patients, the cumulative probabilities of a virological relapse at 1, 12, 24, 48, 60, 96, and 120 months were 25.0%, 35.0%, 41.7%, 43.3%, 43.3%, 46.7%, and 48.3%, respectively. Younger age (HR 1.732, 95%CI: 1.058-2.835, P = 0.02) was predictive of non-virological relapse in HBeAg-positive patients. And achievement of undetectable HBV DNA level within 3 months of treatment discontinuation was associated with decreased rate of virological relapse (HR 0.159, 95%CI: 0.069-0.367 P < 0.01) in HBeAg-negative patients. Despite meeting the requirements for treatment discontinuation, approximately half of the CHB patients treated with lamivudine relapsed. Thus, the antiviral response is not reliably sustained after lamivudine treatment cessation. J. Med. Virol. 89:849-856, 2017. © 2016 Wiley Periodicals, Inc.

Analytical and clinical evaluation of the Abbott RealTime hepatitis B sequencing assay

BACKGROUND

Long-term nucleoside analogue (NA) treatment leads to selection for drug-resistant mutations in patients undergoing hepatitis B virus (HBV) therapy. The Abbott RealTime HBV Sequencing assay (Abbott assay; Abbott Molecular Inc., Des Plaines, IL, USA) targets the reverse transcriptase region of the polymerase gene and as such has the ability to detect NA resistance-associated mutations in HBV.

OBJECTIVES

We evaluated the analytical performance of the Abbott assay and compared its diagnostic performance to that of a laboratory-developed nested-PCR and sequencing method.

STUDY DESIGN

The analytical sensitivity of the Abbott assay was determined using a serially-diluted WHO International Standard. To validate the clinical performances of the Abbott assay and the laboratory-developed assay, 89 clinical plasma samples with various levels of HBV DNA were tested using both assays.

RESULTS

The limit of detection of the Abbott assay, was 210IU/ml and it successfully detected mutations when the mutant types were present at levels ≥20%. Among 89 clinical specimens, 43 and 42 were amplification positive in the Abbott and laboratory-developed assays, respectively, with 87.6% overall agreement (78/89; 95% confidence interval [CI], 78.6-93.4). The Abbott assay failed to detect the minor mutant populations in two specimens, and therefore overall concordance was 85.3% (76/89), and the kappa value was 0.79 (95% CI, 0.67-0.90).

CONCLUSIONS

The Abbott assay showed comparable diagnostic performance to laboratory-developed nested PCR followed by direct sequencing, and may be useful as a routine method for detecting HBV NA resistance-associated mutations in clinical laboratory settings.

X region mutations of hepatitis B virus related to clinical severity

Chronic hepatitis B virus (HBV) infection remains a major health problem, with more than 240 million people chronically infected worldwide and potentially 650000 deaths per year due to advanced liver diseases including liver cirrhosis and hepatocellular carcinoma (HCC). HBV-X protein (HBx) contributes to the biology and pathogenesis of HBV via stimulating virus replication or altering host gene expression related to HCC. The HBV X region contains only 465 bp encoding the 16.5 kDa HBx protein, which also contains several critical cis-elements such as enhancer II, the core promoter and the microRNA-binding region. Thus, mutations in this region may affect not only the HBx open reading frame but also the overlapped cis-elements. Recently, several types of HBx mutations significantly associated with clinical severity have been described, although the functional mechanism in most of these cases remains unsolved. This review article will mainly focus on the HBx mutations proven to be significantly related to clinical severity via epidemiological studies.

Molecular Evolution and Phylodynamics of Acute Hepatitis B Virus in Japan

Hepatitis B virus (HBV) is prevalent worldwide and causes liver diseases, including acute and chronic hepatitis. Ten HBV genotypes (A–J) with distinct geographic distributions have been reported. Cases of acute HBV infection with genotype A have increased in Japan nationwide since the 1990s, mainly through sexual transmission. To investigate the molecular evolution and phylodynamics of HBV genotypes, we collected acute HBV isolates acquired in Japan from 1992–2002. Full genomes were obtained for comprehensive phylogenetic and phylodynamic analysis, with other Japanese HBV sequences from GenBank that were isolated during 1991–2010. HBV genotypes were classified using the maximum-likelihood and Bayesian methods. The GMRF Bayesian Skyride was used to estimate the evolution and population dynamics of HBV. Four HBV genotypes (A, B, C, and H) were identified, of which C was the major genotype. The phylodynamic results indicated an exponential growth between the 1960s and early 1990s; this was followed by a population bottleneck after 1995, possibly linked with successful implementation of a nationwide vaccination program. However, HBV/A increased from 1990 to 2003–2004, and then started to decrease. The prevalence of genotype A has increased over the past 10 years. Phylodynamic inference clearly demonstrates a steady population growth compatible with an ongoing subepidemic; this might be due to the loss of immunity to HBV in adolescents and people being born before the vaccination program. This is the first phylodynamic study of HBV infection in Japan and will facilitate understanding the molecular epidemiology and long-term evolutionary dynamics of this virus in Japan.

Hepatitis B Surface Antigen Quantification across Different Phases of Chronic Hepatitis B Virus Infection Using an Immunoradiometric Assay

BACKGROUND/AIMS

Quantification of hepatitis B surface antigen (HBsAg) is an emerging serologic test and may be useful for identifying treatment strategies for chronic hepatitis B (CHB). This study aimed to evaluate HBsAg titers during the natural course of CHB and identify correlations between HBsAg titers and hepatitis B virus (HBV) DNA concentrations across different CHB phases measured using an immunoradiometric assay (IRMA).

METHODS

CHB phases were defined on the basis of HBV DNA concentrations, the presence of hepatitis B e antigen/antibody (HBeAg/Ab) and serum alanine aminotransferase levels. Serum HBsAg titers and paired HBV DNA concentrations in the different phases of CHB were compared using 627 serum samples.

RESULTS

Mean HBsAg titers were significantly higher in the immunotolerant (IT) phase and immunoreactive (IR) HBeAg-positive phase than in the low-replicative (LR) and HBeAg-negative CHB (ENH) states. The correlation between HBsAg titers and HBV DNA concentrations was modest in the IT (n=36, r=0.804, p<0.001) and IR (n=48, r=0.773, p<0.001) phases, and it was poor in the LR state (n=116, r=0.289, p=0.002); however, no significant correlation was observed in the ENH state (n=67, r=0.146, p=0.237) or in the oral nucleos(t)ide analogue-treated group (n=267).

CONCLUSIONS

HBsAg quantification using IRMA might be useful for discriminating different CHB phases and different stages of chronic liver disease.

Precore/core region mutations of hepatitis B virus related to clinical severity

Despite the availability of an effective vaccine, hepatitis B virus (HBV) infection remains a major health problem, with more than 350 million chronically infected people worldwide and over 1 million annual deaths due to cirrhosis and liver cancer. HBV mutations are primarily generated due both to a lack of proofreading capacity by HBV polymerase and to host immune pressure, which is a very important factor for predicting disease progression and therapeutic outcomes. Several types of HBV precore/core (preC/C) mutations have been described to date. The host immune response against T cells drives mutation in the preC/C region. Specifically, preC/C mutations in the MHC class II restricted region are more common than in other regions and are significantly related to hepatocellular carcinoma. Certain mutations, including preC G1896A, are also significantly related to HBeAg-negative chronic infection. This review article mainly focuses on the HBV preC/C mutations that are related to disease severity and on the HBeAg serostatus of chronically infected patients.

Influence of hepatitis B virus reactivation on the recurrence of HBV-related hepatocellular carcinoma after curative resection in patients with low viral load

It is unclear whether the reactivation of hepatitis B virus (HBV) influences the prognosis of hepatocellular carcinoma (HCC) after resection in patients with chronic hepatitis B. The aim of this study was to identify the influence of HBV reactivation on the recurrence of hepatitis B-related HCC after curative resection in patients with low viral load (HBV DNA <2000 IU/mL). We retrospectively analysed a total of 130 patients who underwent curative resection for HBV-related early stage HCC (single nodule; <5 cm/two or three nodules; <3 cm) with pre-operative HBV DNA levels <2000 IU/mL with serial HBV DNA tests. The predictive factors including HBV reactivation for the recurrence of HBV-related HCC after curative resection were investigated. Fifty-three patients (41%) had HBV reactivation after resection among 130 patients. HBV reactivation was observed in 22 of 53 patients with undetectable baseline HBV DNA and in 31 of 77 patients with detectable baseline HBV DNA. Cumulative recurrence rates after resection at 1, 2 and 3 years were 17.0%, 23.3% and 31.4%, respectively. The multivariable analysis demonstrated that the risk factors for the recurrence were the presence of microvascular invasion (hazard ratio (HR) 2.62, P = 0.003), multinodularity (HR 4.61, P = 0.005), HBV reactivation after resection (HR 2.03, P = 0.032) and HBeAg positivity (HR 2.06, P = 0.044). HBV reactivation after curative resection is associated with the recurrence of HBV-related HCC in patients with low viral load.

Analysis of HBV genotype, drug resistant mutations, and pre-core/basal core promoter mutations in Korean patients with acute hepatitis B

Acute hepatitis B, caused by hepatitis B virus (HBV) strains with drug resistant mutations or pre-core/basal core promoter (PC/BCP) mutations, is a public health concern, because this infection is often associated with poor disease outcome or difficulty in therapeutic choice. The HBV genotype, the prevalence of drug resistant mutations, and PC/BCP mutations in Korean patients with acute hepatitis B were studied. From 2006 to 2008, 36 patients with acute hepatitis B were enrolled prospectively in four general hospitals. Among them, 20 showed detectable HBV DNA (median value was 4.8 log copies/mL). HBV genotyping and analysis of HBV mutations that conferred resistance against lamivudine, adefovir, or entecavir and of PC/BCP mutations were performed using highly sensitive restriction fragment mass polymorphism (RFMP) analysis. All 20 patients were infected with HBV genotype C, which causes almost all cases of chronic hepatitis B in Korea. No patient showed mutations that conferred resistance against lamivudine (L180M, M204V/I), adefovir (A181T, N236S), or entecavir (I169M, A184T/V, S202I/G, M250V/I/L). However, four patients had BCP mutations, and two had PC mutations. Platelet counts were significantly lower in the four patients with PC/BCP mutations compared to those with wild type. In this study, all acute hepatitis B patients had genotype C HBV strains with no drug resistant mutations. However, 20% showed PC/BCP mutations. This highlights the need for further study on the significance of PC/BCP mutations.

Long-term efficacy of tenofovir disoproxil fumarate therapy after multiple nucleos(t)ide analogue failure in chronic hepatitis B patients

BACKGROUND/AIMS

The efficacy of tenofovir disoproxil fumarate (TDF) for the treatment of chronic hepatitis B (CHB) patients following prior treatment failure with multiple nucleos(t)ide analogues (NAs) is not well defined, especially in Asian populations. In this study we investigated the efficacy and safety of TDF rescue therapy in CHB patients after multiple NA treatment failure.

METHODS

The study retrospectively analyzed 52 CHB patients who experienced failure with two or more NAs and who were switched to regimens containing TDF. The efficacy and safety assessments included hepatitis B virus (HBV) DNA undetectability, hepatitis B envelop antigen (HBeAg) seroclearance, alanine transaminase (ALT) normalization and changes in serum creatinine and phosphorus levels.

RESULTS

The mean HBV DNA level at baseline was 5.4 ± 1.76 log10 IU/mL. At a median duration of 34.5 months of TDF treatment, the cumulative probabilities of achieving complete virological response (CVR) were 25.0%, 51.8%, 74.2%, and 96.7% at 6, 12, 24, and 48 months, respectively. HBeAg seroclearance occurred in seven of 48 patients (14.6%). ALT levels were normalized in 27 of 31 patients (87.1%) with elevated ALT at baseline. Lower levels of HBV DNA at baseline were significantly associated with increased CVR rates (p < 0.001). However, CVR rates did not differ between TDF monotherapy or combination therapy with other NAs, and were not affected by mutations associated with resistance to NAs. No significant adverse events were observed.

CONCLUSIONS

TDF is an efficient and safe rescue therapy for CHB patients after treatment failure with multiple NAs.

Tenofovir in the treatment of naïve and refractory chronic Hepatitis B: A single center experience in Saudi Arabia

BACKGROUND/AIMS

Tenofovir disoproxil fumarate (TDF) is a nucleotide analog used in the treatment of chronic hepatitis B (CHB) infection. This study evaluated the efficacy of TDF in achieving undetectable HBV DNA after 48 weeks of treatment in a Saudi cohort of CHB patients.

PATIENTS AND METHODS

This retrospective study included patients treated at a tertiary care center in Saudi Arabia from January 2009 to December 2012. Of the 68 eligible patients, 51 were treatment naïve and 17 were treatment-refractory. Twenty-three patients tested positive for HBeAg. The remaining 45 patients were HBeAg-negative.

RESULTS

The mean HBV DNA viral load decreased from 95 million IU/mL at baseline to 263 IU/mL after 48 weeks of treatment (P < 0.001). Overall, 62% of patients achieved a complete virological response (CVR) and 37% a partial virological response (PVR). Respective CVR and PVR rates according to subgroup were: HBeAg-positive (21.7% and 78.3%) and HBeAg-negative (84.4% and 15.6%). At 48 weeks, HBV DNA was undetectable in 66.7% of treatment-naÏve and 53% of treatment-refractory patients (P = 0.3). Seroconversion occurred in 13 (57%) of HBeAg-positive patients. Two (3%) of the HBeAg-negative patients lost HBsAg at follow up. Mean alanine aminotransferase decreased significantly from 134 U/L before treatment to 37 U/L at 48 weeks (P < 0.001). Significant adverse events were not encountered during the study period.

CONCLUSION

Forty-eight weeks of treatment with TDF reduced HBV DNA to undetectable levels in more than half of our patients regardless of whether they were treatment-naïve or refractory. HBeAg-negative (vs positive) patients experienced a better response rate.

Predisposing factors for recurrence of HBV-related small hepatocellular carcinoma after percutaneous radiofrequency ablation

BACKGROUND. Radiofrequency ablation (RFA) as a curative therapy for hepatocellular carcinoma (HCC) is widely used. The aim of this study was to investigate predisposing factors for HCC recurrence in patients with hepatitis B virus (HBV)-related small HCC after RFA. METHods. A total of 170 patients underwent percutaneous RFA for HBV-related small HCC (≤3 cm in diameter) from January 2008 to December 2010 at Samsung Medical Center. We analyzed the risk factors for recurrence of HCC after RFA. RESULTS. The median follow-up duration was 27.0 months. A total of 89 patients (52%) experienced recurrence after percutaneous RFA. Cumulative recurrence-free rates after RFA at 1-, 3-, and 5 years were 81.3%, 47.2% and 35.7%, respectively. Univariate analysis showed that predisposing factors for HCC recurrence were the multinodularity (hazard ratio (HR) 2.22, p = 0.005), pre-RFA HBV DNA levels ≥2000 IU/mL (HR 1.61, p = 0.025), and Barcelona Clinic Liver Cancer stage A (HR 1.54, p = 0.046). The independent risk factors for recurrence by multivariate analysis were the multinodularity (HR 1.94, p = 0.026) and pre-RFA HBV DNA levels ≥2000 IU/mL (HR 1.57, p = 0.039). CONCLUSION. Multinodularity and HBV DNA levels were associated with the recurrence of HBV-related small HCC after RFA.

Genotypic polymorphisms of hepatitis B virus provide useful information for estimating geographical origin or place of long-term residence of unidentified cadavers

Increasing numbers of unidentified cadavers are a major problem. We have developed a new method for providing identification information that can determine the geographical origin or place of long-term residence of unidentified cadavers based on genotypic polymorphisms of hepatitis B virus (HBV) known to correlate with their geographical distribution. PCR of serum samples detected HBV DNA from 4 (3.9%) of 102 randomly selected Japanese forensic cadavers. Multiplex PCR did not detect multiple HBV genotypes from any single cadaver, confirming the absence of coinfection. Phylogenetic tree analysis based on a 485-bp mutant region of the HBV S gene successfully classified the HBV genotypes into A to J. Among 10 HBV-infected cadavers, 8 had genotype Ce/C2, a genotype prevalent in East Asia, and 2 had genotype Bj/B1, a Japanese-specific genotype. HBV genotypic polymorphisms correlate with the geographical distribution of the virus and thus provide important information for identifying unidentified cadavers infected with HBV.

Treatment strategies using adefovir dipivoxil for individuals with lamivudine-resistant chronic hepatitis B

AIM: To investigate retrospectively the long-term efficacy of various treatment strategies using adefovir dipivoxil (adefovir) in patients with lamivudine-resistant chronic hepatitis B.

METHODS: We included 154 consecutive patients in two treatment groups: the “add-on” group (n = 79), in which adefovir was added to ongoing lamivudine treatment due to lamivudine resistance, and the “switch/combination” group (n = 75), in which lamivudine was first switched to adefovir and then re-added later as needed. The “switch/combination” group was then divided into two subgroups depending on whether participants followed (group A, n = 30) or violated (group B, n = 45) a proposed treatment strategy that determined whether to add lamivudine based on the serum hepatitis B virus (HBV) DNA levels (< 60 IU/mL or not) after 6 mo of treatment (roadmap concept).

RESULTS: The cumulative probability of virologic response (HBV DNA < 60 IU/mL) was higher in group A than in the “add-on” group and in group B (P < 0.001). In contrast, the cumulative probability of virologic breakthrough was lower in the “add-on” group than in group B (P = 0.002). Furthermore, the risk of virologic breakthrough in the multivariate analysis was significantly lower in the “add-on” group than in group A (hazard ratio = 0.096; 95%CI, 0.015-0.629; P = 0.015).

CONCLUSION: The selective combination of adefovir with lamivudine based upon early treatment responses increased the odds of virologic breakthrough relative to the use of uniform combination therapy from the beginning of treatment.

Tenofovir rescue therapy for chronic hepatitis B patients after multiple treatment failures

AIM: To evaluate the efficacy and safety of tenofovir disoproxil fumarate (TDF) for chronic hepatitis B (CHB) patients after multiple failures.

METHODS: A total of 29 CHB patients who had a suboptimal response or developed resistance to two or more previous nucleoside/nucleotide analogue (NA) treatments were included. Study subjects were treated with TDF alone (n = 13) or in combination with lamivudine (LAM, n = 12) or entecavir (ETV, n = 4) for ≥ 6 mo. Complete virologic response (CVR) was defined as an achievement of serum hepatitis B virus (HBV) DNA level ≤ 60 IU/mL by real-time polymerase chain reaction method during treatment. Safety assessment was based on serum creatinine and phosphorus level. Eleven patients had histories of LAM and adefovir dipivoxil (ADV) treatment and 18 patients were exposed to LAM, ADV, and ETV. Twenty-seven patients (93.1%) were hepatitis B e antigen (HBeAg) positive and the mean value of the baseline serum HBV DNA level was 5.5 log IU/mL ± 1.7 log IU/mL. The median treatment duration was 16 mo (range 7 to 29 mo).

RESULTS: All the patients had been treated with LAM and developed genotypic and phenotypic resistance to it. Resistance to ADV was present in 7 patients and 10 subjects had a resistance to ETV. One patient had a resistance to both ADV and ETV. The cumulative probabilities of CVR at 12 and 24 mo of TDF containing treatment regimen calculated by the Kaplan Meier method were 86.2% and 96.6%, respectively. Although one patient failed to achieve CVR, serum HBV DNA level decreased by 3.9 log IU/mL from the baseline and the last serum HBV DNA level during treatment was 85 IU/mL, achieving near CVR. No patients in this study showed viral breakthrough or primary non-response during the follow-up period. The cumulative probability of HBeAg clearance in the 27 HBeAg positive patients was 7.4%, 12%, and 27% at 6, 12, and 18 mo of treatment, respectively. Treatment efficacy of TDF containing regimen was not statistically different according to the presence of specific HBV mutations. History of prior exposure to specific antiviral agents did not make a difference to treatment outcome. Treatment efficacy of TDF was not affected by combination therapy with LAM or ETV. No patient developed renal toxicity and no cases of hypophosphatemia associated with TDF therapy were observed. There were no other adverse events related to TDF therapy observed in the study subjects.

CONCLUSION: TDF can be an effective and safe rescue therapy in CHB patients after multiple NA therapy failures.

A novel multiplex real-time PCR assay for the concurrent detection of hepatitis A, B and C viruses in patients with acute hepatitis

A novel multiplex real-time PCR assay for concurrent detection of hepatitis viruses was evaluated for its clinical performance in screening patients with acute hepatitis. A total of 648 serum samples were collected from patients with acute symptoms of hepatitis. Concurrent detection of nucleic acids of HAV, HBV and HCV was performed using the Magicplex™ HepaTrio Real-time Detection test. Serum nucleic acid levels of HBV and HCV were also quantified by the Cobas® AmpliPrep/Cobas® TaqMan® (CAP/CTM) HBV and HCV tests. Patients’ medical records were also reviewed. Concordance rates between the results from the HepaTrio and the CAP/CTM tests for the detection of HBV and HCV were 94.9% (k = 0.88) and 99.2% (k = 0.98), respectively. The cycle threshold values with the HepaTrio test were also correlated well with the levels of HBV DNA (r = −0.9230) and HCV RNA (r = −0.8458). The sensitivity and specificity of the HepaTrio test were 93.8% and 98.2%, respectively, for detecting HBV infection, and 99.1% and 100.0%, respectively, for HCV infection. For the HepaTrio test, 21 (3.2%) cases were positive for both HBV and HCV. Among the positive cases, 6 (0.9%) were true coinfections. This test also detected 18 (2.8%) HAV positives. The HepaTrio test demonstrated good clinical performance and produced results that agreed well with those of the CAP/CTM assays, especially for the detection of HCV. This assay was also able to detect HAV RNA from anti-HAV IgM-positive individuals. Therefore, this new multiplex PCR assay could be useful for the concurrent detection of the three hepatitis viruses.

Clinical course of chronic hepatitis B patients who were off-treated after lamivudine treatment: analysis of 138 consecutive patients

BACKGROUND/AIMS

Little is known about the long-term outcome of chronic hepatitis B (CHB) patients who discontinued antiviral therapy. We intended to analyze the long-term outcome of CHB patients who discontinued lamivudine therapy and to evaluate predictors for post-treatment outcome.

MATERIAL/METHODS

From 2007 to 2008, 138 lamivudine off-treated CHB patients with alanine aminotransferase normalization were consecutively enrolled. Post-treatment virologic relapse, biochemical breakthrough, hepatitis flare, and retreatment results were retrospectively analyzed.

RESULTS

Among 138 patients, 102 were initially HBeAg-positive at the start of lamivudine treatment. Virologic relapse, biochemical breakthrough, and hepatitis flare were observed in 45.2, 52.9, and 12.7% of HBeAg-positive and 29.4, 30.6, and 8.3% of HBeAg-negative patients during the median follow-up of 28 and 30 months, respectively. The cumulative virologic relapse and biochemical breakthrough rates were significantly lower in patients with HBV DNA <50 copies/mL than 50-104 copies/mL at lamivudine cessation. Hepatitis flare was observed in 4.8 and 11.8% of HBeAg-positive and HBeAg-negative patients with HBV DNA <50copies/mL, respectively. Thirty-eight among 138 patients received retreatment and most of them achieved biochemical (37/38) and virologic response (35/38) within 1 year of retreatment. Undetectable serum HBV DNA (<50 copies/mL) and young age at lamivudine cessation were inversely associated with virologic relapse. Undetectable HBV DNA at cessation, female, and initial HBeAg-negative were inversely associated with biochemical breakthrough.

CONCLUSIONS

Post-treatment virologic relapse and biochemical breakthrough incidence were low in patients who achieved undetectable viral titer at lamivudine cessation. Retreatment after biochemical breakthrough or virologic relapse was safe and effective. Intermittent antiviral therapy might be cautiously considered in appropriately selected CHB patients.

Multiplicative synergistic risk of hepatocellular carcinoma development among hepatitis B and C co-infected subjects in HBV endemic area: a community-based cohort study

Background

There has been limited study on the effect of infection with different hepatitis C virus (HCV) genotypes on the risk of hepatocellular carcinoma (HCC) in hepatitis B virus (HBV) endemic regions of Asia.

Methods

Hazard ratios of HCC development were estimated for HBV and HCV co-infected subjects among a community-based prospective cohort. HCV genotype was determined in HCV RNA-positive samples. Incident HCC cases were identified through linkage to the cancer registry.

Results

HCC incidence was 79 per 100,000 person-years in the study population (50 incident cases among 6,694 individuals within 63,170 person-years with an average of 9.4 years of follow-up); seroprevalence of HBsAg and anti-HCV was 5.2% and 5.6%. Adjusted hazard ratios of HCC by HBsAg positivity and anti-HCV positivity were 13.3 (CI: 7.3-24.4) and 6.7 (CI: 3.6-12.6). HRs of HBV and HCV monoinfection, and HBV/HCV coinfection were 17.1 (CI: 8.4-34.8), 10.4 (CI: 4.9-22.1) and 115.0 (CI: 32.5-407.3). Multiplicative synergistic effect of HBV/HCV coinfection on HCC risk was also observed (synergy index: 4.5, CI: 1.3-15.5). Infection with HCV genotype 1 (HR: 29.7, CI: 13.6-46.8) and mixed infection with genotype 1 and 2 (HR: 68.7, CI: 16.4-288.4) significantly elevated HCC risk, much higher than HBV infection.

Conclusions

The effect of differences in HCV genotype and the multiplicative synergistic effect of HBV/HCV coinfection on HCC risk shown in the present study underline the need for comprehensive identification of hepatitis infection status in order to prevent and control HCC in this HBV endemic area.

Viral response at 6 months is associated with treatment outcome of adefovir add-on therapy for lamivudine-resistance

BACKGROUND AND AIM

  Adefovir add-on therapy is recommended for patients infected with lamivudine-resistant hepatitis B virus (HBV). We aimed to describe the long-term treatment outcome and predictors for good response of adefovir add-on therapy.

METHODS

A total of 559 chronic hepatitis B (CHB) patients who had been treated for at least 12 months with adefovir add-on therapy due to resistance to lamivudine were retrospectively included. Complete virologic response (CVR) was defined as serum HBV DNA <9IU/mL. Viral responses at 6months were classified as PCR negativity, partial virologic response (PVR, HBV DNA <2000 IU/mL), or inadequate virologic response (IVR, HBV DNA≥2000IU/mL).

RESULTS

The median duration of follow-up was 31.5 months (range, 12-56). The cumulative probabilities of CVR during adefovir add-on therapy were 58%, 70%, 78%, and 80% at 12, 24, 36, and 43 months, respectively. The cumulative rates of resistance to adefovir were 0.4%, 0.8%, and 3.1% at 12, 24, and 36 months, respectively. The only baseline factor associated with CVR (hazard ratio 0.83, 95% confidence interval 0.62-0.91, P≤0.001) and resistance to adefovir (hazard ratio 1.925, 95% confidence interval 1.13-3.30, P=0.017) was serum HBV DNA level. Comparison of the cumulative rates of CVR and resistance to adefovir according to viral response at 6months showed significant differences among the three groups (P<0.0001 and P= 0.0005, respectively).

CONCLUSIONS

Pre-treatment HBV DNA level and viral response at 6months is associated with treatment outcome for adefovir-add on therapy in lamivudine resistance.

High HBV-DNA titer in surrounding liver rather than in hepatocellular carcinoma tissue predisposes to recurrence after curative surgical resection

GOALS

In this study the authors intended to investigate the relationship between intrahepatic hepatitis B virus (HBV)-DNA concentrations and posthepatectomy recurrence of HBV-associated hepatocellular carcinoma (HCC).

BACKGROUND

High HBV-DNA level is strongly associated with HCC development in chronic HBV infection and considered to be a risk factor of HCC recurrence.

STUDY

A total of 109 patients with HBV-associated HCC who underwent curative surgical resection were followed up every 3 to 6 months for a median of 82 months. Intrahepatic total HBV-DNA titer was measured in HCC and surrounding liver tissues using a TaqMan probe-based real-time polymerase chain reaction method. HBV-DNA titers in HCC and surrounding liver were compared in accordance with patients' clinical, radiologic, and histopathological characteristics. The relationships between HBV-DNA titers in HCC or surrounding liver tissues and cumulative HCC recurrence rates were determined.

RESULTS

Of the 109 patients, 67 (62%) showed posthepatectomy recurrence of HCC. In all patients, total HBV-DNA titers were significantly higher in HCCs than in surrounding liver tissues (P=0.019). HCC recurred more frequently in patients with higher than those with lower HBV-DNA titers in surrounding liver tissues (P=0.009). In contrast, the HCC recurrence rates were similar in patients with higher and those with lower HBV-DNA titers in HCC specimens (P=0.301). Multivariate analysis showed that tumor size >5 cm (P=0.008), the presence of portal vein thrombus (P=0.001), and high HBV-DNA titer in surrounding liver tissues (P=0.002) were independent risk factors for posthepatectomy HCC recurrence in patients with HBV-associated HCC.

CONCLUSIONS

In patients with HBV-associated HCC, high HBV-DNA titer in surrounding liver rather than in the HCC itself is associated with posthepatectomy HCC recurrence after curative surgical resection.

The change of the quantitative HBsAg level during the natural course of chronic hepatitis B

BACKGROUND

There is insufficient information about HBsAg levels and their correlation with serum hepatitis B virus (HBV) DNA in chronic hepatitis B (CHB).

AIMS

We aimed to describe HBsAg levels during various phases of CHB and to investigate the correlation with serum HBV DNA levels.

METHODS

A total of 645 treatment-naïve Korean CHB patients were included in this retrospective cross-sectional study. They were categorized into immune tolerance (IT, n=56), HBeAg-positive hepatitis (EPH, n=150), inactive carrier (IC, n=274) and HBeAg-negative hepatitis (ENH, n=165). The baseline HBsAg and HBV DNA levels were measured.

RESULTS

The mean HBsAg titres (log IU/ml) differed (P<0.001): IT 4.29, EPH 3.64, IC 2.05 and ENH 3.23. In 645 patients, HBsAg and HBV DNA showed a significant correlation (r=0.693, P<0.001), and this was also observed in the IT, EPH and IC groups (r=0.664, r=0.541, r=0.505, respectively, all P<0.001), but not in the ENH group (r=0.093, P=0.321). Age had a negative correlation with HBsAg (r=-0.451, P<0.001). The cirrhotic patients had a significantly lower HBsAg level than the non-cirrhotic patients (2.41 ± 1.36 vs. 3.02 ± 1.21 log IU/ml, P<0.001).

CONCLUSIONS

The HBsAg level varied significantly in different phases of CHB and was correlated with HBV DNA during the IT, EPH and IC phases. These findings can provide additional information to understand the natural course and pathogenesis of CHB.

JGH Foundation emerging leadership lecture. Significance of hepatitis B virus genotypes and mutations in the development of hepatocellular carcinoma in Asia

Advances in molecular biology technology in the last two decades have allowed detailed study of the viral mutations and genomic heterogeneity of hepatitis B virus (HBV). The first mutant discovered was precore stop codon mutation. It was reported in HBeAg-negative patients and initially thought to associate with fulminant hepatitis. Subsequent studies have suggested that it is merely one of the mechanisms of losing HBeAg by the virus. Another mutation that can downregulate the production of HBeAg is the basal core promoter mutation, which is located in the X gene upstream of the precore region. Based on the configuration of codon 15 and the stability of the epsilon of the precore region, these two mutants will be differentially selected during the course of HBeAg seroconversion. The most common HBV genotypes in South-East Asia are genotype B and C HBV. The higher hepatocellular carcinoma (HCC) risk of genotype C HBV has been confirmed by longitudinal studies in Hong Kong and Taiwan. One possible carcinogenic mechanism is its association with basal core promoter mutation, which has also been found to be a risk factor of HCC. Within genotype C HBV, subgenotype Cs is predominant in South-East Asia and subgenotype Ce is predominant in East Asia. Subgenotype Ce HBV has been found to have the highest risk of HCC as compared with subgenotype Cs or genotype B HBV. The understanding of the carcinogenic mechanisms of these HBV strains may shed light into future therapeutics in the prevention and treatment of HBV-related HCC.

Partial virological response to entecavir in treatment-naive patients with chronic hepatitis B

BACKGROUND

The proposed definition of a partial virological response (PVR) to nucleos(t)ide analogue therapy in the 2009 European Association for the Study of the Liver (EASL) guidelines is based on limited evidence, especially in terms of the cutoff HBV DNA level and the time point at which to judge it. This study assessed optimal PVR criteria for predicting virological response (VR) at week 96 in treatment-naive patients with chronic hepatitis B (CHB) receiving entecavir (ETV).

METHODS

A total of 175 patients (126 men, 49 women) who completed 96 weeks of first-line ETV therapy were prospectively recruited. For predicting VR at week 96, the area under the receiver operating characteristic curve (AUC) was used to find the optimal time point and the Youden index was used to calculate the optimal cutoff HBV DNA level.

RESULTS

After 96 weeks of ETV therapy, 139 (79.4%) patients achieved VR. The AUC at week 48 was significantly better than that at week 24 for predicting VR at week 96 (P=0.023). The optimal cutoff HBV DNA level at week 48 was 35 IU/ml. Forty-one (23.4%) patients met this PVR criteria of ETV (HBV DNA level >35 IU/ml at week 48).

CONCLUSIONS

An HBV DNA level >35 IU/ml at week 48 is the optimal PVR criteria for predicting non-VR at week 96 in treatment-naive patients with CHB who are receiving ETV. This study supports the proposed EASL PVR for ETV based on scientific evidence.

Risk of hepatitis B virus reactivation in patients with asthma or chronic obstructive pulmonary disease treated with corticosteroids

BACKGROUND AND OBJECTIVE

Reactivation of hepatitis B virus (HBV) is thought to be associated with immunosuppressive treatments, but insufficient information is available on the effect of corticosteroids. The aim of this study was to evaluate the risk of HBV reactivation in hepatitis B surface antigen-seropositive patients with asthma or COPD, who were treated with systemic corticosteroids (SCS) in addition to inhaled corticosteroids (ICS).

METHODS

Patients with asthma or COPD (n = 198), who were hepatitis B surface antigen-seropositive and had been treated with ICS, were identified retrospectively. To evaluate the additional effects of SCS, the SCS group was divided into those who received intermittent or continuous SCS (≥3 months of continuous SCS treatment), and into those who received low-dose (≤20 mg/day of prednisolone) or medium-to-high-dose SCS. The study outcome was HBV reactivation.

RESULTS

HBV reactivation occurred in 11.1% of patients in the SCS group, which was significantly higher than the reactivation rate in the ICS group. HBV reactivation was more frequent in the SCS group compared with the ICS group (OR 3.813, 95% CI: 1.106-13.145, P = 0.032), and in the continuous and medium-to-high-dose SCS subgroups compared with the ICS group (OR 5.719, 95% CI: 1.172-27.905, P = 0.048 and OR 4.884, 95% CI: 1.362-17.511, P = 0.014, respectively).

CONCLUSIONS

These results suggest that addition of SCS to ICS increases the risk of HBV reactivation, especially when SCS are administered chronically or at high doses.

[Development of clevudine resistance after switching from lamivudine in a patient with chronic hepatitis B]

Background/Aims

Newly developed and potent antiviral agents suffer from the problem of drug resistance. Multidrug resistance is a major impediment in the treatment of patients with chronic hepatitis B (CHB). In line with American Association for the Study of Liver Diseases guidelines, adefovir dipivoxil (ADV) add-on therapy is recommended in the case of lamivudine resistance, while tenofovir disoproxil fumarate (TDF) is recommended for ADV or entecavir (ETV) resistance. TDF is currently not available in Korea. ADV+ETV combination therapy may be a viable alternative to TDF in patients with either ADV or ETV resistance. However, the efficacy of ADV+ETV combination therapy in patients with CHB and multidrug resistance is unclear. This study investigated the efficacy of ADV+ETV combination therapy in patients with multidrug resistance.

Methods

Twenty-five patients were enrolled and were administered ADV+ETV combination therapy for at least 6 months. Blood was drawn at baseline and at 3, 6, 9, and 12 months after commencing treatment, and the following blood parameters were analyzed: alanine transaminase, hepatitis B e-antigen (HBeAg), anti-hepatitis B e-antigen, and hepatitis B virus (HBV) DNA levels. The initial virological response (IVR) was defined as an HBV DNA level of <4 log₁₀ copies/mL after 6 months of combination therapy.

Results

The IVR rate was 76%. The proportion of patients with a high viral load (≥5.0 log) dropped from 76% at baseline to only 5% after 6 months of treatment. The biochemical response rate during the first 6 months was 71%. HBeAg was lost in 2 patients (10%).

Conclusions

ADV+ETV combination therapy induced a good IVR in CHB patients who were refractory to more than 2 antiviral agents. This regimen may be a good alternative to TDF in Korea, where that drug is not available.