Antiviral therapy of chronic hepatitis B: opportunities and challenges in Asia

Ten-Year Changes in the Hepatitis B Prevalence in the Birth Cohorts in Korea: Results From Nationally Representative Cross-Sectional Surveys

To compare the prevalence of hepatitis B virus (HBV) infection over a 10-year period in terms of population-level trends, we established hypothetical birth cohorts that represented each 10-year interval age group.We used data from the Korean National Health and Nutrition Examination Surveys conducted between 1998 to 2001 and 2008 to 2011. Trends in the HBV infection were calculated using data from individuals aged 20 to 59 years in 1998 to 2001 and those aged 30 to 69 years in 2008 to 2011.In 2008 to 2011, the prevalence of HBV infection, as measured using serum HBV surface antigen (HBsAg) seroprevalence, among participants aged 30 to 69 years was 4.2% (95% CI = 3.7-4.7%), which represents a 1.3% absolute change and 20% change in prevalence ratio, which was significant compared with the prevalence among those aged 20 to 59 years in 1998 to 2001 (5.5%, 95% CI = 4.7-6.3%). The prevalence of HBV infection decreased most in the lowest income group, with marginal significance in males (P = 0.06) and significance in females (P = 0.03). In terms of education, females with at least a high school education showed a significant decrease (P = 0.03).Using a birth cohort approach, the prognosis for HBV infection in terms of death or hospitalization, or resolution upon antiviral treatment of their HBV infections, identified by a decrease in the HBsAg seroprevalence was worse in the lower income group and in females with higher education. We postulate that these socioeconomic inequalities were caused by alcohol consumption, disparities in liver cancer surveillance, and access to antiviral treatment because of cost and reimbursement guidelines.

Impact of partial reimbursement on hepatitis B antiviral utilization and adherence

AIM: To determine the impact of partial reimbursement for antivirals on antiviral utilization and adherence for chronic hepatitis B patients.

METHODS: This was a retrospective cohort study. Two separate cohorts were enrolled, including 14163 and 16288 chronic hepatitis B outpatients, respectively. These patients were referred to Beijing You’an Hospital before and after the new partial reimbursement for antivirals, which was implemented on July 1, 2011. Demographic characteristics (including medical insurance status), routine biochemical, virological and serology laboratory test results, and antiviral agents’ prescription information were collected from an electronic database. Patients were also defined as new and existing patients according to treatment history. Antiviral utilization, medication possession ratio and persistence rate were calculated and compared among the patients with different characteristics. A questionnaire survey was conducted among 212 randomly sampled outpatients from the same hospital to confirm the validity of the electronic database. Propensity score matching was used to adjust the distribution of patient’s characteristics which may influence the antiviral utilization. χ² test or ANOVA was adopted and multivariate logistic regression was used to determine the factors associated with antiviral utilization and good adherence.

RESULTS: A total of 13364 outpatients from each cohort were enrolled after the propensity score matching. The antiviral utilization rate for the insured patients increased from 57.4% to 75.9% (P < 0.0001) after the reimbursement, and the rate among those who paid out-of-pocket increased from 54.9% to 56.7% (P = 0.028). Approximately 71% of the patients had a medication possession ratio of more than 80% in each cohort before reimbursement. This increased to 79.2% and 73.1% for insured patients and those who paid out-of-pocket, respectively (P < 0.0001). Insured patients and those who paid out-of-pocket had the similar persistence rates before reimbursement. But after reimbursement, insured patients had higher persistence rates than those who paid out-of-pocket at 6 (86.5% vs 81.5%, P < 0.0001), 9 (79.7% vs 69.9%, P < 0.0001), 12 (73.4% vs 61.9%, P < 0.0001), and 15 mo (66.6% vs 53.1%, P < 0.0001). The reimbursement could significantly improve adherence for the insured patients than those who paid out-of-pocket even after adjusting other covariates, with an interaction odds ratio of 1.422 (95%CI: 1.220-1.657, P < 0.0001). The questionnaire survey supported the validity of the electronic database.

CONCLUSION: The reimbursement policy shows a positive impact on antiviral utilization as well as adherence for insured chronic hepatitis B patients.

Clinical events after cessation of lamivudine therapy in patients recovered from hepatitis B flare with hepatic decompensation

BACKGROUND & AIMS

Before guidelines were issued, many patients with hepatitis B flare and hepatic decompensation had discontinued lamivudine therapy instead of indefinite therapy. We investigated their outcomes.

METHODS

We performed a retrospective cohort study of 263 consecutive patients with chronic hepatitis B (94 with cirrhosis) who recovered from a flare of hepatitis with hepatic decompensation and were followed after cessation of lamivudine therapy. Clinical events that occurred during the follow-up period were assessed by chart review and analysis of results from retrospective assays.

RESULTS

The mean duration of lamivudine therapy was 12.1 ± 8.6 months; data were collected from patients for 89.1 ± 38.7 months after therapy ended. In the first year off therapy, 29.9% of patients had clinical relapse, 16.2% had hepatitis flares, and 8.2% had hepatic decompensation. There was no significant difference in the incidence of hepatic decompensation between patients with and without cirrhosis. Hepatocellular carcinoma developed in 14 patients 20-109 months after cessation of therapy, with 5-year cumulative incidence of 5.2% in patients with cirrhosis. Three patients with cirrhosis died of hepatic decompensation 38-76 months after cessation of therapy (5-year cumulative mortality, 2.9%). Multivariate analyses showed that men were more likely than women to have recurrence of hepatic decompensation (hazard ratio [HR], 4.339; P = .014). Liver cirrhosis (HR, 2.766; P = .041) and age (HR, 1.054; P = .023) increased risk for hepatocellular carcinoma.

CONCLUSIONS

Cessation of lamivudine therapy after recovery from hepatitis B flare with decompensation was safe for most patients. However, 8.2% develop decompensation within 1 year and can be rescued by timely retreatment. With close monitoring, the stopping strategy could be a feasible alternative to indefinite therapy, especially in low resource settings.

Significant reduction in end-stage liver diseases burden through the national viral hepatitis therapy program in Taiwan

A national viral hepatitis therapy program was launched in Taiwan in October 2003. This study aimed to assess the impact of the program on reduction of end-stage liver disease (ESLD) burden. Profiles of national registries of households, cancers, and death certificates were used to derive incidence and mortality of ESLDs from 2000 to 2011. Age-gender-adjusted incidence and mortality rates of hepatocellular carcinoma (HCC) and chronic liver diseases (CLDs) and cirrhosis of adults ages 30-69 years were compared before and after launching the program using Poisson's regression models. A total of 157,570 and 61,823 patients (15%-25% of those eligible for reimbursed treatment) received therapy for chronic hepatitis B and C, respectively, by 2011. There were 42,526 CLDs and cirrhosis deaths, 47,392 HCC deaths, and 74,832 incident HCC cases occurred in 140,814,448 person-years from 2000 to 2011. Male gender and elder age were associated with a significantly increased risk of CLDs and cirrhosis and HCC. Mortality and incidence rates of ESLDs decreased continuously from 2000 to 2003 (before therapy program) through 2004-2007 to 2008-2011 in all age and gender groups. The age-gender-adjusted rate ratio (95% confidence interval; P value) in 2008-2011 was 0.78 (0.76-0.80; P < 0.001) for CLDs and cirrhosis mortality, 0.76 (0.75-0.78; P < 0.005) for HCC mortality, and 0.86 (0.85-0.88; P < 0.005) for HCC incidence using 2000-2003 as the reference period (rate ratio = 1.0).

CONCLUSIONS

The national viral hepatitis therapy program has significantly reduced the mortality of CLDs and cirrhosis and incidence and mortality of HCC.

Hepatitis B flares in chronic hepatitis B: pathogenesis, natural course, and management

Hepatitis B flare, defined as an event with abrupt rise of alanine aminotransferase (ALT) levels to >5 times the upper limit of normal during chronic hepatitis B virus (HBV) infection, is considered to be the result of a human leukocyte antigen-I restricted, cytotoxic T lymphocyte mediated immune response against HBV and its downstream mechanisms. It may occur spontaneously, during or after antiviral therapy and in the setting of immunosuppression and/or chemotherapy. The clinical spectrum of hepatitis B flares varies from asymptomatic to symptomatic and typical overt acute hepatitis, even with hepatic decompensation or failure. Flares may also occur in viraemic patients with cirrhosis with higher incidence of decompensation/mortality, hence requiring immediate antiviral therapy. An upsurge of serum HBV DNA and hepatitis B surface antigen levels usually precedes the abrupt rise of ALT levels. Rising or stable and high HBV DNA during flares represent ineffective immune clearance and further hepatocytolysis, even hepatic decompensation, may occur. Such patients require immediate antiviral therapy. In contrast, bridging hepatic necrosis and/or alpha-fetoprotein levels >100 ng/ml or decreasing HBV DNA during flares represent a more effective immune clearance and frequently leads to seroclearance of HBV DNA and/or hepatitis B e antigen with remission. If patients are non-cirrhotic and there is no concern of developing decompensation, patients may be observed for 3-6 months before deciding on the need of antiviral therapy. Severe and repeated flares are prone to develop into decompensation or lead to the development of cirrhosis, thus a timely treatment to prevent the hepatitis B flare is better than to cope with the flare. Screening, monitoring and prophylactic or pre-emptive antiviral therapy is mandatory for patients who are going to receive immunosuppressants or chemotherapy.

Factors associated with alcohol consumption in hepatitis B carriers: a nationwide study in the Republic of Korea

This study was conducted to investigate the prevalence of alcohol consumption and identify the sociodemographic factors associated with alcohol consumption among individuals with hepatitis B virus(HBV) infection. We used data from the Korean National Health and Nutrition Examination Surveys, a nationwide survey conducted between 2007 and 2011. “Monthly alcohol consumption” was defined as having consumed alcohol at least once per month during the past year, and “high-risk alcohol consumption” was defined as having consumed alcohol twice or more per week and, for males, having consumed at least 60 g of alcohol on one occasion or, for females, having consumed at least 40 g of alcohol on more than one occasion. The prevalence of monthly alcohol consumption was 53.2%, and that of high-risk alcohol consumption was 11.8% among HBV carriers. Less education was associated with both monthly and high-risk alcohol consumption(OR = 1.75 [95% CI = 1.02−3.02] for monthly alcohol consumption among those with less than a high school education; OR = 2.48 [95% CI = 1.19−5.17] for high-risk alcohol consumption among those with less than a high school education and OR = 2.02 [95% CI = 1.12−3.64] among those with a high school education). Additionally, smoking and being male increased the risk of alcohol consumption, and older age and having a normal body mass index decreased the risk. HBV carriers who were less educated, overweight, and smokers were more likely to consume alcohol or meet criteria for high-risk drinking. Health policies and intervention programs aimed at promoting a generally healthy lifestyle in HBV carriers should consider educational inequalities and alcohol consumption.

Impact of a new reimbursement program on hepatitis B antiviral medication cost and utilization in Beijing, China

Background

Hepatitis B virus (HBV) infection is a significant clinical and financial burden for chronic hepatitis B (CHB) patients. In Beijing, China, partial reimbursement on antiviral agents was first implemented for the treatment of CHB patients in July 1, 2011.

Aims

In this study, we describe the medical cost and utilization rates of antiviral therapy for CHB patients to explore the impact of the new partial reimbursement policy on the medical care cost, the composition, and antivirals utilization.

Methods

Clinical and claims data of a retrospective cohort of 92,776 outpatients and 2,774 inpatients with non-cirrhotic CHB were retrieved and analyzed from You'an Hospital, Beijing between February 14, 2008 and December 31, 2012. The propensity score matching was used to adjust factors associated with the annual total cost, including age, gender, medical insurance type and treatment indicator.

Results

Compared to patients who paid out-of-pocket, medical cost, especially antiviral costs increased greater among patients with medical insurance after July 1, 2011, the start date of reimbursement policy. Outpatients with medical insurance had 16% more antiviral utilization; usage increased 3% among those who paid out-of-pocket after the new partial reimbursement policy was implemented.

Conclusions

Direct medical costs and antiviral utilization rates of CHB patients with medical insurance were higher than those from paid out-of-pocket payments, even after adjusting for inflation and other factors. Thus, a new partial reimbursement program may positively optimize the cost and standardization of antiviral treatment.

Prevalence of and factors influencing impaired glucose tolerance among hepatitis B carriers: a nationwide cross-sectional study in the Republic of Korea

Diabetes is associated with a poor prognosis for liver disease, particularly in chronic hepatitis carriers. We investigated the prevalence of factors associated with impaired glucose tolerance (IGT) including diabetes and impaired fasting glucose (IFG) among individuals with hepatitis B virus (HBV) infection.We used data from the Korean National Health and Nutrition Examination Survey, a nationwide cross-sectional survey conducted between 2007 and 2011. Sociodemographic information was collected using a structured questionnaire. The HBV surface antigen, liver enzymes, and lipid profile were measured from blood samples.IFG was found in 18.1% of HBV carriers and 19.3% of noncarriers (P = 0.25). Diabetes was observed in 10.0% of HBV carriers and 12.2% of noncarriers (P = 0.08). Lower level of educational attainment was associated with a higher prevalence of IGT: high school education (odds ratio [OR] = 1.94 [95% confidence interval (CI) 1.14-3.29] and less than a high school education (OR = 3.20 [95% CI, 1.66-6.15] vs more than or equal to a college education. Elevated alanine transaminase and triglyceride by 10 were associated with increased risk of IGT (OR = 1.10 [95% CI, 1.01-1.20] and OR = 1.04 [95% CI, 1.01-1.07], respectively). Being a man and older in age were associated with a higher prevalence of IGT, and individuals with a low body mass index were at lower risk for IGT.Given the synergistic effect of diabetes and HBV infection on liver disease prognosis, we recommend targeted IGT screening and follow-up for HBV carriers. These efforts should include health policies and intervention programs aimed at reducing educational disparities and encouraging early control of elevated liver enzymes or lipid profiles.

Two-phase fed-batch modification for 48 hour peak expression of hepatitis B surface antigen in Pichia pastoris shake flask system

A study of the Mut+ phenotype for the expression of recombinant hepatitis B surface antigen (HBsAg) in Pichia pastoris strain GS115 using the pPIC3.5K vector with a two-phase fed-batch protocol in a shake flask system is described. Expression levels of HBsAg protein of 6.74 g L−1 Dry Cell Weight (DCW) and 26.07 mg L−1 of HBsAg concentration were achieved 48 h from the induction point which added to a 120 h reduction in production period in comparison with MutS expression (168 h). The use of the pPIC3.5K-HBsAg plasmid in the Mut+ phenotype enhanced the expression of HBsAg by a nearly 13 times higher volumetric productivity in the first 24 h and 35 times higher at peak production concentration. Comparison of AOX expression cassettes relative to the HBsAg gene in the role of mRNA secondary structure during translation initiation revealed that HBsAg possesses lower folding stability with AOX1 Mut+ phenotype. The results from this study demonstrated that expression of HBsAg with Mut+ AOX1 promoter is adequate as an alternative for the production of HBsAg. In addition, the AOX promoter of the Mut+ phenotype was observed to be better suited for HBsAg expression, which correlates with the ease of translation initiation under shake flask conditions.

Association of nucleos(t)ide analogue therapy with reduced risk of hepatocellular carcinoma in patients with chronic hepatitis B: a nationwide cohort study

BACKGROUND & AIMS

Treatment for hepatitis B virus infection reduces the risk of hepatocellular carcinoma (HCC). However, the long-term protective effects for subgroups of patients with chronic hepatitis B are unclear.

METHODS

We conducted a retrospective nationwide cohort study using data from Taiwan's National Health Insurance Research Database (from January 1, 1997, through December 31, 2010). Cumulative incidences were calculated and multivariable analyses were carried out after adjusting for competing mortality. Propensity scores were used to match 21,595 patients with chronic hepatitis B who received nucleoside analogue therapy for at least 90 days (treated cohort) with 21,595 untreated patients with chronic hepatitis B (controls), who received hepatoprotectants for at least 90 days. Data were collected from the treated cohort for a mean period of 3.46 years and from controls for 5.24 years.

RESULTS

The treated cohort had a significantly lower 7-year incidence of HCC (7.32%; 95% confidence interval [CI], 6.77%-7.87%) than controls (22.7%; 95% CI, 22.1%-23.3%; P < .001). After adjusting for competing mortality and other confounders, nucleos(t)ide analogue treatment was associated with a reduced risk of HCC, with an adjusted hazard ratio of 0.37 (95% CI, 0.34-0.39; P < .001). Sensitivity analyses confirmed the association between nucleos(t)ide analogue treatment and reduced risk of HCC. Age, sex, cirrhosis, and diabetes mellitus modified this association.

CONCLUSIONS

Based on a retrospective, nationwide study in Taiwan, nucleoside analogue therapy use is associated with reduced risk of HCC in patients with chronic hepatitis B virus infection.

Evaluation of HBV DNA decay kinetics in patients containing both rtM204V/I mutant and wild-type HBV subpopulations during tenofovir DF (TDF) monotherapy or combination therapy with emtricitabine (FTC)/TDF

Tenofovir disoproxil fumarate (TDF) is recommended as treatment for chronic hepatitis B patients harboring lamivudine-associated resistance mutations (LAM-R, rtM204V/I ± rtL180M). This study evaluated the clinical response of rtM204V and rtM204I subpopulations to TDF by comparing their early viral load decay kinetics to wild-type (WT) subpopulations in chronic hepatitis B patients harboring rtM204V/I prior to initiating TDF or emtricitabine (FTC)/TDF therapy. Allele-specific PCR assays capable of detecting rtM204V or rtM204I subpopulations as low as 0.5% were developed and used to assess patient samples from a Phase 3b study evaluating TDF and FTC/TDF treatment in LAM-R patients. Baseline samples (n = 280) were quantified for rtM204V/I subpopulations and rtM204V or rtM204I subpopulations were detected in 269/273 (98.5%) baseline samples with a range of 0.7% to >95%. On-treatment analyses were conducted for seventeen patients (TDF, n = 8; FTC/TDF, n = 9) that harbored baseline WT and either rtM204V or rtM204I (no rtM204V/I mixtures) and HBV DNA ≥1,000 copies/ml at/after week 4. The median change in HBV DNA through week 12 for WT and rtM204V/I subpopulations was similar, -2.64 and -3.30 log10  copies/ml, respectively, with no significant difference between TDF and FTC/TDF treatment. In conclusion, rtM204V/I subpopulations demonstrate similar early HBV DNA decline kinetics to WT subpopulations during treatment with either TDF or FTC/TDF. These results demonstrate that TDF is similarly active against both WT and rtM204V/I subpopulations in vivo.

Real-world application of the roadmap model in chronic hepatitis B patients with telbivudine therapy

BACKGROUND

The roadmap concept provides a strategy to maximize hepatitis B virus suppression and minimize drug resistance by add-on or switching therapy in patients with a suboptimal response at Week 24. The efficacy of this strategy in routine clinical practice remains to be validated.

OBJECTIVE

The aim of our study was to validate the roadmap concept in the treatment of chronic hepatitis B, and to investigate the virologic efficacy and kinetics of quantitative hepatitis B surface antigen (qHBsAg) during telbivudine therapy in a real-world setting.

METHODS

A prospective, cohort study enrolled 96 consecutive, treatment-naïve patients with chronic hepatitis B receiving telbivudine therapy. At Week 24, only 17 of 42 (40%) partial or inadequate responders (hepatitis B virus DNA 60-2000 and >2000 IU/mL, respectively) followed the roadmap model and consented to adefovir add-on therapy. The remaining patients continued to receive telbivudine monotherapy.

RESULTS

At Week 96, none of the patients receiving adefovir add-on therapy, and 28% of patients receiving telbivudine monotherapy, either partial or inadequate responders, developed genotypic resistance (P = 0.03). Poor early qHBsAg kinetics (an increase in qHBsAg >0.4 log IU/mL at Week 12) was the only significant predictor of genotypic resistance (adjusted hazard ratio = 13.83; 95% CI, 1.79-106.76; P = 0.01). Telbivudine monotherapy was efficacious in 94% of partial responders who did not have poor early qHBsAg kinetics, remaining free of drug resistance after 2 years.

CONCLUSIONS

The application of the roadmap model with add-on adefovir therapy prevented genotypic resistance. However, telbivudine monotherapy achieved a good response in the majority of partial responders who did not have poor early qHBsAg kinetics. Poor early qHBsAg kinetics was an early predictor of genotypic resistance at Week 96. Modification of the roadmap model to incorporate early qHBsAg kinetics may further optimize the efficacy of the treatment strategy of hepatitis B virus.

Chinese medicine syndrome distribution of chronic hepatitis B virus carriers in immunotolerant phase

OBJECTIVE

To explore Chinese medicine (CM) syndrome distribution of chronic hepatitis B virus (HBV) carriers in immunotolerant phase (ITP).

METHODS

One hundred and eighty-five chronic HBV carriers in ITP, seen in the Third Affiliated Hospital of Sun Yat-sen University from May 2009 to December 2010, were admitted in an observational study under the guidance of CM. Patients' CM symptoms and signs, demographics, liver biochemistries, and qualitative HBV DNA were recorded in the questionnaires. CM syndromes were then differentiated to 15 detailed types and analyzed by generalization. Lastly, the location, pathogenic factors and nature of the disease were also assessed.

RESULTS

When CM syndrome patterns were differentiated to 15 types, there were 27 (15%) no syndrome cases, 94 (50%) single syndrome cases and 64 (35%) compound syndromes cases. The main detailed syndromes included Liver (Gan)-qi depression (LQD), Kidney (Shen)-qi deficiency (KQD), Spleen (Pi)-qi deficiency (SQD) and Kidney-yang deficiency (KYAD). After CM syndromes generalized to five types, their frequency was Spleen-Kidney deficiency (SKD)>LQD>inner dampness-heat retention (IDHR)>Liver-Kidney deficiency (LKD)>blood stasis blocking collateral (BSBC). SKD and LQD occupied 64%. The disease location included Liver, Gallbladder (Dan), Spleen, Stomach (Wei) and Kidney. The pathogenic factors were mainly qi stagnation, qi deficiency, yang deficiency, concurrently dampness-heat and blood stasis. The deficiency syndrome was more than excess syndrome in its nature.

CONCLUSIONS

Most of chronic HBV carriers in ITP have their CM syndrome, and the most common types are SKAD, LQD. This study suggests that the natural history may be improved through breaking the state of immune tolerance or shorten the time of ITP by strengthening Spleen-Kidney and reliving Liver qi.

Dynamic comparison between Daan real-time PCR and Cobas TaqMan for quantification of HBV DNA levels in patients with CHB

BACKGROUND

Hepatitis B virus (HBV) DNA levels are crucial for managing chronic hepatitis B (CHB). It was unclear whether Daan real-time polymerase chain reaction test (Daan test) or COBAS TaqMan HBV DNA Test (Cobas TaqMan) was superior in measuring different HBV DNA levels in clinical specimens.

METHODS

We enrolled 67 treatment-naïve, HBV surface antigen-positive CHB patients (high baseline viral levels) who received either lamivudine/adefovir or entecavir. Serum samples were tested at baseline and treatment week 24 using the Daan test and Cobas TaqMan.

RESULTS

In the 67-baseline samples, the HBV DNA levels with the Cobas TaqMan (7.90 ± 0.73 log10 IU/mL) were significantly greater than those of the Daan test (7.11 ± 0.44 log10 IU/mL; P < 0.001). Of the 67 24-week samples (low viral levels), the Cobas TaqMan detected 59 (88.1%; 8 undetected); the Daan test detected 33 (49.3%; 34 undetected; P < 0.001). The Cobas TaqMan detected HBV DNA in 26 of 34 samples undetectable by the Daan test (range, 1.4-3.7 log10 IU/mL) or 38% of samples (26/67). The reductions in viral load after 24 weeks of oral antiviral treatment in the 33 samples that were positive for both the Daan test and the Cobas TaqMan test were significantly different (3.59 ± 1.11 log10 IU/mL versus 4.87 ± 1.58 log10 IU/mL, respectively; P = 0.001). Spearman correlation analysis showed positive correlation between results from two tests (rp = 0.602,P<0.001). The HBV genotypes and the anti-viral treatment did not affect the measurements of the HBV DNA by the Daan assay and the Cobas Taqman assay.

CONCLUSION

The Cobas Taqman was more sensitive at low viral loads than the Daan test and the change from complete to partial virological response could affect clinical decisions. The Cobas Taqman may be more appropriate for detection of HBV DNA levels.

Efficacy of tenofovir in adefovir-experienced patients compared with treatment-naive patients with chronic hepatitis B

BACKGROUND

Tenofovir (TDF) has similar antiviral efficacy in both treatment-naive and lamivudine-resistant chronic hepatitis B (CHB) patients. Data on TDF use in patients with adefovir (ADV) resistance is inconsistent. The aim of our study was to assess antiviral efficacy of TDF against nucleoside analogue-naive (NN) and ADV-resistant (ADV-R) CHB and suboptimal responders to ADV (ADV-S).

METHODS

A database of 135 CHB patients treated with TDF was analysed. A total of 37 patients with incomplete data were excluded and analysis was performed in 98 (44 NN, 30 ADV-R and 24 ADV-S). Patients with primary ADV-R mutations had either A181T/V or N236T mutations or both. HBV DNA was measured at 3-month intervals until month 24. Primary outcome measures were comparison of the decline of HBV DNA between the three treatment groups.

RESULTS

NN patients had higher baseline HBV DNA compared with ADV-R and ADV-S patients (6.08 log10 IU/ml versus 5.53 and 4.88, respectively; P=0.002). By exponential regression analysis, HBV DNA decline kinetics differed between the three groups. HBV DNA decline was faster in NN patients compared to ADV-R and ADV-S CHB patients (P=0.002 and P=0.004, respectively). Undetectable HBV DNA was achieved in 77.2%, 60% and 75% of NN, ADV-R and ADV-S CHB patients, respectively, at month 12 (P= not significant).

CONCLUSIONS

HBV DNA decline is slower in ADV-experienced patients compared with treatment-naive patients. The clinical significance of this slow response may be important in patients with critical liver reserve and high viral load. Optimal combination treatment (TDF+ entecavir) could be considered in these patients.

Off-therapy durability of response to entecavir therapy in hepatitis B e antigen-negative chronic hepatitis B patients

The optimal duration of nucelos(t)ide analog (Nuc) treatment in hepatitis B e antigen (HBeAg)-negative patients with chronic hepatitis B virus (HBV) infection is unknown. The Asian Pacific Association for the Study of the Liver (APASL) guidelines recommend that treatment can be discontinued if undetectable HBV-DNA has been documented on three occasions ≥ 6 months apart. This study aimed to test this stopping rule in HBeAg-negative chronic hepatitis B (CHB) patients treated with entecavir (ETV). Ninety-five patients (39 cirrhosis) were treated with ETV for a median of 721 (395-1,762) days before stopping therapy and were then monitored with serum HBV DNA and alanine aminotransferase (ALT) at least every 3 months. Within 1 year after stopping ETV therapy, "clinical relapse" (an episode of ALT elevation >2 × upper limit of normal plus HBV-DNA >2,000 IU/mL) occurred in 43 (45.3%) of the 95 patients. Of the 39 cirrhosis patients, 17 (43.6%) relapsed and one (2.6%) developed decompensation. The median duration until relapse was 230 days (74.4% >6 months). Logistic regression analysis showed that baseline HBV-DNA ≤ 2 × 10(5) IU/mL was the only significant independent factor for sustained response. The 1-year relapse rate was 29% in patients with a baseline HBV DNA ≤ 2 × 10(5) IU/mL versus 53% in those with HBV DNA >2 × 10(5) IU/mL (P = 0.027). For the latter, consolidation therapy >64 weeks reduced the relapse rate to 33.3% in patients without cirrhosis.

CONCLUSION

With an overall 1-year relapse rate of 45% and 29% in those with a baseline serum HBV DNA ≤ 2 × 10(5) IU/mL, the APASL stopping rule for HBeAg-negative CHB patients with proper off-therapy monitoring is adequate even in patients with cirrhosis. Consolidation therapy >64 weeks seems more appropriate for those with higher baseline HBV DNA.

Sulfamoylbenzamide derivatives inhibit the assembly of hepatitis B virus nucleocapsids

Chronic hepatitis B virus (HBV) infection, a serious public health problem leading to cirrhosis and hepatocellular carcinoma, is currently treated with either pegylated alpha interferon (pegIFN-α) or one of the five nucleos(t)ide analogue viral DNA polymerase inhibitors. However, neither pegIFN-α nor nucleos(t)ide analogues are capable of reliably curing the viral infection. In order to develop novel antiviral drugs against HBV, we established a cell-based screening assay by using an immortalized mouse hepatocyte-derived stable cell line supporting a high level of HBV replication in a tetracycline-inducible manner. Screening of a library consisting of 26,900 small molecules led to the discovery of a series of sulfamoylbenzamide (SBA) derivatives that significantly reduced the amount of cytoplasmic HBV DNA. Structure-activity relationship studies have thus far identified a group of fluorine-substituted SBAs with submicromolar antiviral activity against HBV in human hepatoma cells. Mechanistic analyses reveal that the compounds dose dependently inhibit the formation of pregenomic RNA (pgRNA)-containing nucleocapsids of HBV but not other animal hepadnaviruses, such as woodchuck hepatitis virus (WHV) and duck hepatitis B virus (DHBV). Moreover, heterologous genetic complementation studies of capsid protein, DNA polymerase, and pgRNA between HBV and WHV suggest that HBV capsid protein confers sensitivity to the SBAs. In summary, SBAs represent a novel chemical entity with superior activity and a unique antiviral mechanism and are thus warranted for further development as novel antiviral therapeutics for the treatment of chronic hepatitis B.

Dynamics of hepatitis B virus quasispecies heterogeneity and virologic response in patients receiving low-to-moderate genetic barrier nucleoside analogs

We characterized the early dynamics of hepatitis B virus (HBV) quasispecies evolution during the first weeks of antiviral therapy with low-to-moderate genetic barrier antiviral drugs and associated these data with antiviral response patterns. Fifteen chronic hepatitis B patients (men, 10; mean age, 34; HBeAg positive, 6) who received lamivudine or telbivudine for at least 52 weeks were included. HBV DNA was extracted from serum, and a 910-bp fragment covering domains A-F of the reverse transcriptase region was amplified, cloned and sequenced. Parameters of quasispecies heterogeneity, genetic diversity and complexity were calculated and were correlated with complete virologic response, defined as undetectable HBV DNA at week 52. Nine patients achieved complete virologic response during the observational period. While baseline HBV DNA levels and HBeAg status were associated with virologic response, baseline quasispecies complexity and diversity of responders showed no significant difference to those of nonresponders (P > 0.05). However, at week 4, quasispecies complexity of nonresponders was significantly higher compared with that of responders on the nucleotide level (P = 0.01) and the aa level (P = 0.04). The number of synonymous substitutions per synonymous site dropped significantly in responders at week 4 (P = 0.04), while there was no difference in nonresponders. The HBV quasispecies complexity at the early stage of antiviral therapy (week 4) with the low-to-moderate genetic barrier nucleoside analogs lamivudine or telbivudine was associated with subsequent virologic response. Further studies are needed to confirm HBV quasispecies evolution as additional predictive marker for beneficial treatment outcome.

Efficacy of telbivudine treatment for hepatitis B e antigen-positive chronic hepatitis B patients with poor response to adefovir dipivoxil

Telbivudine (LdT) has demonstrated potent antiviral activity in nucleos(t)ide analogue (NA)-naïve chronic hepatitis B patients (CHB), but data on its efficacy in NA-experienced patients are limited. The aim of this study was to investigate the effect of LdT in hepatitis B e antigen-positive CHB patients with poor response to initial adefovir dipivoxil (ADV). Forty-two CHB patients with HBV DNA > 4 log10  copies/mL after 12 months of ADV monotherapy were enroled in the study and thereafter treated with LdT 600 mg daily for 18 months. Telbivudine led to a rapid decrease in viral load, and viral replication was persistently suppressed with a reduction of 2.26 log10  copies/mL 18 months after LdT treatment. The rates corresponding to virological and biochemical response at the end of observation were 97.6% (41/42) and 65.8% (25/38), respectively. HBeAg loss was found in 30.8% (12/39) of patients, while HBeAg/anti-HBe seroconversion was found in 17.9% (7/39). Only one patient was detected to have LdT-associated mutation, and no severe adverse events were reported. Optimization therapy with LdT monotherapy may be a good choice for CHB patients with poor response to ADV, and switching to LdT may be the most cost-effective rescue therapeutic strategy for patients with poor response to initial ADV monotherapy.

Anti-hepatitis B virus lignans from the root of Streblus asper

Four new lignans, strebluslignanol F (1), (7'R,8'S,7″R,8″S)-erythro-strebluslignanol G (2), isomagnaldehyde (3) and isostrebluslignanaldehyde (4), along with 12 known lignans (5-16) were isolated from the ethyl acetate-soluble part of MeOH extract of the root of Streblus asper. Their structures were elucidated through various spectroscopic methods, including 1D NMR ((1)H NMR, (13)C NMR), 2D NMR (HMQC, HMBC and NOESY) and HRMS. The stereochemistry at the chiral centers was determined using CD spectra, as well as analyses of coupling constants and optical rotation data. The isolated lignans were evaluated for their anti-HBV activities in vitro using the HBV transfected HepG2.2.15 cell line. The most active lignans, (7'R,8'S,7″R,8″S)-erythro-strebluslignanol G, magnolol, isomagnolol and isolariciresinol, exhibited significant anti-HBV activities with IC50 values of 1.58, 2.03, 10.34 and 3.67 μM, respectively, for HBsAg with no cytotoxicity, and of 3.24, 3.76, 8.83 and 14.67 μM, respectively, for HBeAg with no cytotoxicity. (7'R,8'S,7″R,8″S)-erythro-Strebluslignanol G and magnolol showed significant anti-HBV activities to inhibit the replication of HBV DNA with the IC50 values of 9.02 and 8.67 μM, respectively.

Combining Oxymatrine or Matrine with Lamivudine Increased Its Antireplication Effect against the Hepatitis B Virus In Vitro

Some recent clinical reports have shown that the combination of oxymatrine, a phyto-derived drug, with lamivudine (3TC) could improve its curative effect against hepatitis B virus (HBV) infection. However, the experimental data in support of this combination strategy are lacking. In this study, we investigated the anti-HBV activity of the combination of 3TC and either oxymatrine or matrine on HepG2 2.2.15 in vitro. The activities of the combination and the solo compound, each in different concentrations, were compared on the 3rd, 6th, and 9th experimental days. The cytotoxicity results showed that the nontoxic concentrations of both oxymatrine and matrine to HepG2 2.2.15 cells were 800 μg/mL. We found that the single use of oxymatrine below 100 μg/ml, matrine below 200 μg/ml, and 3TC below 30 μg/ml showed weak inhibitory effects on the secretion of hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg), and HBV-DNA in culture media; the combination of 3TC (30 μg/ml) with oxymatrine (100 μg/ml) or matrine (100 μg/ml) showed significant inhibitory effects that were higher than or equivalent to the single use of 3TC at 100 μg/ml. The results provide a new impetus to develop novel, multicomponent anti-HBV drugs through the combination of natural products with nucleoside analogs to enhance their activity.

Serum levels of tissue inhibitor of metalloproteinase-1 are correlated with liver fibrosis in patients with chronic hepatitis B

OBJECTIVE

To investigate the relationship between tissue inhibitor of metalloproteinase-1 (TIMP-1) expression and the severity of liver fibrosis in chronic hepatitis B (CHB) patients, and to explore the diagnostic value of serum TIMP-1.

METHODS

A total of 159 CHB patients underwent liver biopsy for the analysis of liver fibrosis stages and inflammation. Serum TIMP-1 was determined by ELISA. Hyaluronic acid (HA), procollagen type III (PCIII), collagen type IV (CIV), laminin (LN), and FIB-4 index were determined and calculated, and diagnostic accuracy was analyzed using receiver operating characteristic (ROC) curve.

RESULTS

Serum levels of TIMP-1 were associated with the grade of liver inflammation in CHB patients (r = 0.695, P < 0.01), especially in those without fibrosis or with stage 1 fibrosis, and were also positively correlated with liver fibrosis in CHB patients (r = 0.854, P < 0.01), particularly in those with inflammation at grade 1, 2 and 3. The area under the ROC curve (AUROC) of serum TIMP-1 was 0.918 for significant liver fibrosis (≥stage 2), and a sensitivity of 89.4% and specificity of 83.6% were obtained with a cut-off value of ≥174.5 ng/mL of serum TIMP-1, which were higher than that of HA, CIV and FIB-4 index.

CONCLUSION

TIMP-1 is a valuable single biomarker for the evaluation of significant fibrosis in CHB patients.

Nucleos(t)ide analogues treatment outcome in genotype B and C chronic hepatitis B

Background:

Hepatitis B genotypes influence the course and severity of the disease.

Aim:

To compare the treatment outcome of chronic hepatitis B genotype B and C patients after treating with nucleos(t)ide analogues for six months.

Patients and Methods:

Forty chronic hepatitis B patients attending the liver clinic of Hospital for Tropical diseases, Bangkok, were studied in retrospective cohort design. Six genotype B patients (15%) and thirty-four genotype C patients (85%) were treated. Serum hepatitis B viral load, serum alanine amino transferase level, HBeAg status and alpha-feto protein level were measured at the time of starting nucleos(t) analogues therapy, and six months later. Besides, achievement of undetectable viral load was assessed in patients with normal serum alanine amino transferase compared to patients with high serum alanine amino transferase level.

Results:

After six months of nucleos (t) analogues treatment, achievement of undetectable hepatitis B viral load was higher in genotype B patients (66.7%) than in genotype C patients (42.4%) (Relative Risk=1.57, 0.79-3.14). Biochemical remission, HBeAg seroconversion and tumor marker levels between the two groups were not significantly different. Moreover, achievement of undetectable hepatitis B viral load was significantly higher in normal alanine amino transferase level (75%) than in patients with high serum alanine amino transferase level (33.3%) on nucleos(t)ide analogue treatment (Relative Risk=2.25, 1.20- 4.20).

Conclusion:

Chronic hepatitis B treatment outcome between genotype B and C were not significantly different. Patients with normalized serum alanine amino transferase level tend to achieve undetectable viral load after nucleoside analogues treatment.

Anti-hepatitis B virus constituents from the stem bark of Streblus asper

Seven compounds, (7'S,8'S)-trans-streblusol A, (7'R,8'S)-erythro-streblusol B, (7'S,8'S)-threo-streblusol B, 8'R-streblusol C, streblusquinone, (8R,8'R)-streblusol D, and streblusol E, along with 15 known compounds (8-22) were isolated from the n-butanol-soluble part of the MeOH extract of stem bark of Streblus asper. Their structures were elucidated through application of extensive spectroscopic methods, including ESI-MS and 2D NMR spectroscopy (HMQC and HMBC). The stereochemistry at the chiral centers was determined using CD spectra, as well as analyses of coupling constants and optical rotation data. The isolated lignans and allylbenzene derivatives were evaluated for their anti-HBV activities in vitro using the HBV transfected Hep G2.2.15 cell line. The most active compounds, magnolol and 9-β-xylopyranosyl-isolariciresinol, exhibited significant anti-HBV activities with IC(50) values of 2.03 and 6.58μM for secretion of HBsAg, with no cytotoxicity, and of 3.76 and 24.86μM for secretion of HBeAg, with no cytotoxicity.

Knowledge, attitudes and practices among people with chronic hepatitis B attending a hepatology clinic in Malaysia: a cross sectional study

Background

Hepatitis B (HBV) is the leading cause of cirrhosis and hepatocellular carcinoma worldwide. This study assessed the knowledge, attitudes and practices of people with chronic HBV and the associated factors.

Methods

This cross-sectional study was conducted at an outpatient adult hepatology clinic at a tertiary hospital in Kuala Lumpur. A self-administered questionnaire was administered on a one-to-one basis to assess knowledge, attitudes, and lifestyle practices of people with chronic HBV.

Results

The response rate was 89% (n = 483/543). Participants had a mean age of 46.3 (±14.7) years and the mean duration of HBV from time of diagnosis was 12.2 (±8.8) years. The mean knowledge score was 12.57/20 (standard deviation: ±4.4, range: 0–19). Participants aged 30–39 years, with higher educational attainment, employed in professional jobs, longer duration of diagnosis and those without cirrhosis had significantly higher knowledge scores. Age, education level and duration of diagnosis were significant predictors of the knowledge score on standard multiple regression analysis. More than half of the participants were worried of spreading HBV infection to family and friends and worried since the diagnosis. A third of the participants (33.5%) were embarrassed to reveal their diagnosis to the public but most of them (93.6%) would inform their family. Those who reported feeling worried since their diagnosis were more likely to be middle-aged, of Malay ethnicity, have shorter duration of diagnosis of less than 10 years and have received therapy. About half of the participants (50.6%) did not share dining utensils and the majority (93.2%) believed that HBV can be transmitted by sharing of eating and drinking utensils. Older patients were significantly less likely to share utensils. Those who felt worried since diagnosis had significant higher knowledge of HBV.

Conclusion

The findings highlight the stigma and misconceptions that still exist among the HBV patients. More patient and public education about HBV and its prevention are essential to increase awareness and to demystify the disease.

A survey on the current trends in the management of hepatitis B in China

OBJECTIVE

Hepatitis B virus (HBV) infection is a highly endemic disease in China. The guidelines of the European Association for the Study of the Liver and the Asian Pacific Association for the Study of the Liver have improved in recent years. Here, we present a survey of physicians in terms of trends in the management of HBV at a teaching hospital in Southwest China.

METHODS

A questionnaire adopted from an earlier Spanish study was used. Physicians in an affiliated hospital of a Chinese medical university were surveyed.

RESULTS

A total of 120 (100%) physicians (including 68 fellows) answered the questionnaire voluntarily. Eighty percent (96/120) reported experience in the treatment of hepatopathy. Although a huge majority (90.9%, 109/120) were aware of the Chinese consensus recommendations on HBV, only 51.8% (62/120) correctly identified the indications for the treatment of chronic hepatitis B and 42.5% (51/120) correctly described the end-points in treating HBeAg-positive or HBeAg-negative chronic hepatitis. Serum HBV-DNA levels were used to monitor therapy by 84.2% (101/120) of the respondents, the HBV drug resistance test was used by 77.5% (93/120) of the responders, and antiviral prophylaxis was recommended by 65% (78/120) for HBV carriers who would receive immunosuppressive therapy. About 27.5% (33/120) recommended interferon or pegylated interferon as the initial treatment for HBeAg-positive patients; 93.3% (112/120) recommended oral antiviral therapy to HBeAg-negative patients. Physicians working at teaching hospitals were significantly more likely to recommend antiviral prophylaxis for HBV patients who receive immunosuppressive therapy than physicians working at nonuniversity hospitals (83 vs. 51%; P<0.001).

CONCLUSION

The inadequate management of chronic hepatitis B by Chinese physicians calls for an improvement in education, especially for physicians in county hospitals or clinics.

Asian-Pacific consensus statement on the management of chronic hepatitis B: a 2012 update

Large volume of new data on the natural history and treatment of chronic hepatitis B virus (HBV) infection have become available since 2008. These include further studies in asymptomatic subjects with chronic HBV infection and community-based cohorts, the role of HBV genotype/naturally occurring HBV mutations, the application of non-invasive assessment of hepatic fibrosis and quantitation of HBV surface antigen and new drug or new strategies towards more effective therapy. To update HBV management guidelines, relevant new data were reviewed and assessed by experts from the region, and the significance of the reported findings was discussed and debated. The earlier "Asian-Pacific consensus statement on the management of chronic hepatitis B" was revised accordingly. The key terms used in the statement were also defined. The new guidelines include general management, indications for fibrosis assessment, time to start or stop drug therapy, choice of drug to initiate therapy, when and how to monitor the patients during and after stopping drug therapy. Recommendations on the therapy of patients in special circumstances, including women in childbearing age, patients with antiviral drug resistance, concurrent viral infection, hepatic decompensation, patients receiving immune suppression or chemotherapy and patients in the setting of liver transplantation and hepatocellular carcinoma, are also included.

Anticarcinogenic impact of interferon therapy on the progression of hepatocellular carcinoma in patients with chronic viral infection

Hepatocellular carcinoma (HCC) is mainly caused by a persistent infection due to the hepatitis B or hepatitis C virus. The number of HCC cases is increasing in Asian and African countries, as well as in European and American countries. Interferon (IFN) therapy, used for type B chronic liver diseases, inhibits hepatic carcinogenesis in patients with compensated cirrhosis. However, there is insufficient evidence that IFN therapy inhibits hepatic carcinogenesis in patients with chronic hepatitis B. There are few cases of HCC due to chronic hepatitis B, and long-term follow-up periods verifying the inhibitory effect of IFN on hepatic carcinogenesis have not been obtained. To improve the prognosis of type B chronic liver diseases, it is important that hepatitis treatment follows guidelines in which a patient's age and the extent of hepatic fibrosis are taken into account. As for chronic hepatitis C, since a sustained virological response (SVR) in IFN therapy inhibits hepatic carcinogenesis and improves prognosis, treatment that aims for an SVR while taking into consideration host-sided and virus-sided factors is recommended for patients with type C chronic liver diseases. In areas with low incidence of HCC (e.g. USA), a large number of cases and a long-term follow-up period are needed before it can be accepted that IFN therapy inhibits hepatic carcinogenesis. After locally curative treatment of HCC, IFN therapy suppresses recurrence and improves survival rates.

High-resolution melting and real-time PCR for quantification and detection of drug-resistant HBV mutants in a single amplicon

BACKGROUND

Antiviral therapy by nucleoside/nucleotide analogues (NAs) effectively reduces HBV replication in chronic hepatitis B (CHB) patients. Because long-term NA treatments will eventually select for drug-resistant mutants, early detection of mutants and frequent monitoring of viral loads is crucial for successful NA therapy. Because no efficient test for one-tube quantification and qualification of various HBV-resistant mutants exists, we propose to use high-resolution melting (HRM) analysis in combination with real-time PCR to achieve this unmet need.

METHODS

We developed a single amplicon for detecting HBV mutants resistant to lamivudine (LMV), adefovir (ADV) and entecavir (ETV), which are commonly used for CHB treatment. Our design consists of two steps: real-time PCR for viral quantification, and hybridization probe HRM analysis for detection of specific drug-resistant mutants.

RESULTS

Assay quantification was accurate (R=0.98) for viral loads from 10(3) to 10(9) copies/ml. HRM analysis produced distinct melting temperatures that clearly distinguished the mutants, rtM204V/I (LMV), rtA181V and rtN236T (ADV), and rtT184G and rtM250V (ETV), from their respective wild types. The assay detected mutants at only 10-25% of the HBV population. The clinical applicability of this assay was tested in a pilot study with serial samples from patients receiving LMV treatment.

CONCLUSIONS

Flexibility, speed and cost-efficiency are additional benefits unique to our assay. The clinical sample results further support the feasibility of applying our design to frequent and long-term monitoring of CHB patients receiving NA treatments in the clinical setting.

Towards the eradication of hepatitis B in Taiwan

Viral hepatitides are important public health problems in humans. The etiologic agents were not identified until 1965, when Baruch S. Blumberg found the relationship of Australia antigen to serum hepatitis. The antigen was found to be the surface antigen of the hepatitis B virus (HBV). This observation launched a new era in the diagnosis, prevention and treatment of hepatitis B. Over 15-20 years, the natural history of HBV infection was elucidated, and more importantly, an effective vaccine became available. The routes of transmission were also made clear, rendering effective interruption of the transmission possible. The vaccine together with effective interruption of the transmission contributed greatly to the control of HBV infection. However, these measures do very little for those who have already been chronically infected. Fortunately, specific therapies against chronic hepatitis B started to appear about 10-15 years before, and the treatments have improved substantially in the last few years. Although far from perfect, effective means to treat those who are chronically infected now exist. In Taiwan, acute and chronic liver diseases were rampant as early as the beginning of the last century. Studies around 1975, showed an extremely high prevalence of chronic hepatitis B infection in the general population (15-20%), and 80-90% of the chronic liver diseases and hepatocellular carcinoma were caused by chronic infection with the HBV. This important health problem caught the attention of the government in the late 1970s, and a government-sponsored control program was finalized in 1981. Accordingly, a mass vaccination program against hepatitis B, primarily aiming at immunizing newborn infants, was launched on July 1, 1984. Twenty years after implementation of the program, the hepatitis B carrier rate in children covered by the program decreased by 85%, from ∼ 15% to <1%. Most importantly, the deadly sequela of hepatocellular carcinoma in the vaccinees was also found to decrease in parallel. This is the first time that a human cancer was prevented by vaccination. Despite the success, there are still some who were born after implementation of the program but were not prevented from developing chronic hepatitis B infection and hepatocellular carcinoma. Non-compliance to the vaccination schedule, breakthrough infection and intrauterine infection are the causes of the failure. At present, we have effective measures for immunizing susceptible individuals, interrupting the routes of transmission and treating the chronically infected. The time for considering the elimination or even the eradication of HBV infection has come. This is especially true for countries where hepatitis B infection is not endemic. Nevertheless, with the admirable results achieved in the past, Taiwan should also think about elimination/eradication of hepatitis B, even though it will certainly be much more difficult than in the non-endemic countries. In exploring the possibility of eliminating/eradicating hepatitis B in Taiwan, we reviewed the epidemiology of hepatitis B, and analyzed the problems that remain to be tackled in Taiwan. We hope that Taiwan can take further steps towards the elimination or eradication of hepatitis B.

HBV-carriers: When is monitoring and surveillance sufficient? (point of view)

Medications currently available for the treatment of hepatitis B virus (HBV) infection are highly effective but not curative. The current paradigm is to recognize patients who require long-term treatment (with its inconveniences) among the majority of healthy carriers who do not need treatment. International guidelines have been established to identify patients requiring treatment but differences concerning the cut-off levels for viral load and transaminases, or need for liver biopsy, compromise their interpretation. IMMUNE TOLERANCE PHASE: Patients with strictly defined typical forms (HBeAg-positive, normal transaminases level, very high viral load HBV-DNA more than 2 × 10(6) IU) have very limited liver injury and do not require treatment. Patients with atypical forms (low viral load HBV-DNA less than 2 × 10(6) IU) have a potential risk of more severe histological lesions, but the need for liver biopsy and treatment remains a matter of debate. Immune tolerant patients aged over 40 years should be treated because of the higher risk of hepatocellular carcinoma, even without cirrhosis. ACTIVE PHASE HBEAG-POSITIVE OR NEGATIVE: Typical forms with elevated viral load and transaminases level should be treated. Mild hepatitis with moderately elevated transaminases levels (1-2 times upper limit of normal) can cause variable degrees of liver damage, and liver biopsy is necessary. HBeAg-positive hepatitis with very high transaminases levels have a very high rate of spontaneous HBe seroconversion. Hepatitis with high transaminases levels but low viral (HBV-DNA less than 2000 UI) is possible in HBe-negative patients but unusual in HBe-positive patients. Another cause of liver disease could be involved (hepatitis D, steatosis, alcohol). INACTIVE PHASE: In the typical form, patients have a normal transaminases level and HBV-DNA less than 2000 IU; histological lesions are in general minimal. Treatment is not indicated. Atypical forms with normal transaminases levels but elevated HBV-DNA more than 2000 IU remain problematic. Forms with high-normal transaminases levels have a higher risk of complications. In the event of inactive cirrhosis, treatment is indicated if replication persists, even at a low level.

Simultaneous determination of metacavir and its metabolites in rat plasma using high-performance liquid chromatography with tandem mass spectrometric detection (LC-MS/MS)

A sensitive and selective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the simultaneous determination of metacavir and its two metabolites in rat plasma was developed and validated. Tinidazole was used as an internal standard and plasma samples were pretreated with one-step liquid-liquid extraction. In addition, these analytes were separated using an isocratic mobile phase on a reverse-phase C18 column and analyzed by MS in the selected reaction monitoring mode. The monitored precursor to product-ion transitions for metacavir, 2',3'-dideoxyguanosine, O-methylguanine and the internal standard were m/z 266.0 → 166.0, m/z 252.0 → 152.0, m/z 166.0 → 149.0 and m/z 248.0 → 202.0, respectively. The standard curves were found to be linear in the range of 1-1000 ng/mL for metacavir, 5-5000 ng/mL for 2',3'-dideoxyguanosine and 1-1000 ng/mL for O-methylguanine in rat plasma. The precision and accuracy for both within- and between-batch determination of all analytes ranged from 2.83 to 9.19% and from 95.86 to 111.27%, respectively. No significant matrix effect was observed. This developed method was successfully applied to an in vivo pharmacokinetic study after a single intravenous dose of 20 mg/kg metacavir in rats.

Future aspects of therapy for hepatitis B virus infection: value of surrogate markers, innovative therapy, and global collaboration

Both optimism and frustration exist regarding therapy for patients with chronic hepatitis B virus infection. Due to the recent advent of several drugs with potent antiviral capacities and comparatively low rates of adverse effects, considerable optimism has developed regarding the treatment of these patients. Chronic hepatitis B is now a treatable disease, and suppression of hepatitis B virus replication, normalization of alanine aminotransferase levels, seronegativity/seroconversion of hepatitis B e antigen and hepatitis B surface antigen, and decreased hepatic inflammation and liver fibrosis have been documented in chronic hepatitis B virus-infected patients treated with antiviral therapy. In contrast, many frustrations regarding antiviral therapy for chronic hepatitis B have arisen, because the disease, although treatable, is not curable. The present regimens of antiviral therapy modulate some intermediate parameters or so-called surrogate markers in chronic hepatitis B virus-infected patients, but usually fail to improve all intermediate parameters or ultimate clinical outcomes. In addition, major concerns remain about the applicability and use of antiviral drugs in developing and resource-constrained countries in which healthcare delivery systems do not support the proper use of antiviral therapy. New and more effective therapeutic regimens for chronic hepatitis B patients are needed that take into account potential surrogate markers of treatment outcomes and allow for effective collaboration between resource-constrained and advanced countries.

Comparison of HIV-, HBV-, HCV- and co-infection prevalence between Chinese and Burmese intravenous drug users of the China-Myanmar border region

Background

Co-infection with HIV and HCV and/or HBV is highly prevalent in intravenous drug users (IDUs). Because of the proximity to the “Golden Triangle”, HIV prevalence among the IDUs is very high in the China-Myanmar border region. However, there are few studies about co-infection with HIV and HCV and/or HBV, especially in the region that belongs to Myanmar.

Methods

721 IDUs, including 403 Chinese and 318 Burmese, were investigated for their HIV, hepatitis B virus (HBV), and hepatitis C virus (HCV) serological status. Statistical analysis was performed to evaluate the differences of the epidemic situation between the Chinese IDUs and the Burmese IDUs.

Results

Among the Chinese IDUs and the Burmese IDUs, HCV infection was the most prevalent (69.0% vs 48.1%, P<0.001), followed by HBV (51.6% vs 43.1%, P<0.05) and HIV (33.7% vs 27.0%, P>0.05). Besides, there were more HIV-HBV co-infected IDUs (20.1% vs 11.3%, P<0.005), and HIV-HCV co-infected IDUs (31.8% vs 23.9%, P<0.05) in China than in Myanmar, as well as HIV-HBV-HCV triple infection (19.1% vs 10.4%, P<0.005).

Conclusion

Co-infection with HIV and HCV and/or HBV is highly prevalent among the IDUs in the China-Myanmar border region. The HIV epidemic appears to be in a downward trend, compared with previous reports. However, all infections were more prevalent among the Chinese IDUs than among the Burmese.

Chronic hepatitis B in Asia-new insights from the past decade

Chronic hepatitis B virus (HBV) infection is a major health problem in the Asia-Pacific region. In the past decade, much progress has been made in the understanding and management of this disease. The introduction of universal vaccination has significantly reduced the incidence of perinatal infection in most Asia-Pacific countries. As the majority of the adult population have not been immunized at birth, we are still facing a large population of young HBV-infected patients in the coming two decades. The study of long-term longitudinal databases has provided deeper insight into the clinical significance of HBV DNA suppression, hepatitis B e antigen (HBeAg) seroconversion and hepatitis B surface antigen (HBsAg) seroclearance in chronic hepatitis B. With a better understanding on the natural history of HBV infection, one can now stratify the risk of chronic hepatitis B patients for adverse clinical outcomes and use this to individualize management. The introduction of non-invasive assessment of liver fibrosis can potentially reduce the necessity of liver biopsy. There have also been great advances in the development of antiviral therapy in the past decade. However, the high cost of HBV antiviral drugs poses major challenges to health authorities in many Asia-Pacific countries. Properly performed cost-effective analysis and understanding on the best timing of stopping antiviral drugs will be important to facilitate the most appropriate allocation of resources.

Hepatitis B e antigen seroconversion: a critical event in chronic hepatitis B virus infection

BACKGROUND

Replication of hepatitis B virus (HBV) is the primary driver of disease progression and clinical outcomes in patients with chronic hepatitis B (CHB), but other factors, such as hepatitis B e antigen (HBeAg) status, also influence disease course. The importance of HBeAg seroconversion is underscored by current CHB treatment guidelines that recommend limiting the duration of antiviral therapy in HBeAg-positive patients who achieve seroconversion.

AIMS

A 2-day meeting of leading hepatologists with extensive experience managing patients with CHB in the Asia-Pacific region was held with the overall goals of reviewing and evaluating (1) available data on the relationship between HBeAg seroconversion and clinical outcomes for patients with HBeAg-positive CHB, and (2) the ways in which seroconversion should influence patient management.

CONCLUSIONS

It was agreed that HBeAg seroconversion is an important serologic end point for patients with CHB and that achieving this goal should be an important consideration in treatment selection. Patients with HBeAg-positive CHB should consider pegylated interferon if they are aged < 40 years (especially women), have lower HBV DNA levels, can afford this treatment, and have a lifestyle that would support adherence to injection therapy. Alternatively, nucleos(t)ide analogs are recommended in patients with alanine aminotransferase levels ≥ 2 × the upper limit of normal, HBV DNA levels < 9 log(10) IU/ml, and compensated CHB. Entecavir, telbivudine, and tenofovir may be used as first-line therapy; they can be administered as a finite therapeutic course in HBeAg-positive patients who seroconvert. Telbivudine and tenofovir should be considered in women of child-bearing potential.

Comparison of the efficacy of lamivudine and telbivudine in the treatment of chronic hepatitis B: a systematic review

Background

Chronic viral hepatitis B remains a global public health concern. Currently, several drugs, such as lamivudine and telbivudine, are recommended for treatment of patients with chronic hepatitis B. However, there are no conclusive results on the comparison of the efficacy of lamivudine (LAM) and telbivudine (LdT) in the treatment of chronic hepatitis B.

Results

To evaluate the comparison of the efficacy of LAM and LdT in the treatment of chronic hepatitis B by a systematic review and meta-analysis of clinical trials, we searched PUBMED (from 1990 to April 2010), Web of Science (from 1990 to April 2010), EMBASE (from 1990 to April 2010), CNKI (National Knowledge Infrastructure) (from 1990 to April 2010), VIP database (from 1990 to April 2010), WANFANG database (from 1990 to April 2010), the Cochrane Central Register of Controlled Trials and the Cochrane Database of Systematic Review. At the end of one-year treatment, LdT was better than LAM at the biochemical response, virological response, HBeAg loss, therapeutic response, while less than at the viral breakthrough and viral resistance, but there was no significant difference in the HBeAg seroconversion and HBsAg response. LdT was better than LAM at the HBeAg seroconversion with prolonged treatment to two years.

Conclusions

In summary, LdT was superior in inhibiting HBV replication and preventing drug resistance as compared to LAM for CHB patients. But LdT may cause more nonspecific adverse events and can lead to more CK elevation than LAM. It is thus recommended that the LdT could be used as an option for patients but adverse events, for example CK elevation, must be monitored.

RNA Interference inhibits hepatitis B virus of different genotypes in vitro and in vivo

Background

Hepatitis B virus (HBV) infection increases the risk of liver disease and hepatocellular carcinoma. Small interfering RNA (siRNA) can be a potential new tool for HBV therapy. Given the high heterogeneity of HBV strains and the sensitivity towards sequences changes of siRNA, finding a potent siRNA inhibitor against the conservative site on the HBV genome is essential to ensure a therapeutic application.

Results

Forty short hairpin RNA (shRNA) expression plasmids were constructed to target conserved regions among nine HBV genotypes. HBV 1.3-fold genome plasmids carrying various genotypes were co-transfected with shRNA plasmids into either Huh7 cells or mice. The levels of various viral markers were examined to assess the anti-HBV efficacy of siRNA. Four (B245, B376, B1581 and B1789) were found with the ability to potently inhibit HBV RNA, DNA, surface antigen (HBsAg), e antigen (HBeAg) and core antigen (HBcAg) expression in HBV genotypes A, B, C, D and I (a newly identified genotype) in Huh7 cells and in mice. No unusual cytotoxicity or off-target effects were noted.

Conclusions

Such siRNA suggests an alternate way of inhibiting various HBV genotypes in vitro and in vivo, promising advances in the treatment of HBV.

Chronic hepatitis B: past, present, and future

There have been major advances in the field of hepatitis B (HBV) over the last few decades. These advances have resulted in the understanding of the natural history of chronic HBV infection, effective vaccines against the virus, sensitive assays for screening and monitoring of treatment, and effective treatments for viral suppression, all leading to improved outcomes. Debates and controversies remain, however, over the ideal management strategies of patients with chronic hepatitis B. To eradicate HBV, the global community needs to improve current preventive, screening, and treatment strategies.

Hepatitis B virus DNA level predicts hepatic decompensation in patients with acute exacerbation of chronic hepatitis B

BACKGROUND & AIMS

Acute exacerbations of chronic hepatitis B virus (HBV) infection can lead to hepatic decompensation. It is important to identify factors that predict the development of hepatic decompensation during exacerbation so that antiviral therapy can be initiated immediately.

METHODS

Acute exacerbation, defined by an abrupt increase in alanine aminotransferase (ALT) levels to >5-fold the upper limit of normal, occurred in 110 hepatitis B e antigen (HBeAg)-seropositive non-cirrhotic patients (138 episodes). The patients were monitored every 1 to 2 weeks for serum levels of ALT, bilirubin, albumin, and prothrombin. Sex, age, HBV genotype, ALT level, HBV viral load, and the causes (spontaneous or relapse from antiviral treatment) of exacerbation were included in multivariate logistic regression analyses. The receiver operating characteristic curve was used to identify the optimal cut-off value of serum HBV DNA level to identify patients at risk for decompensation.

RESULTS

Seven of the 138 episodes of acute exacerbation (5.1%) resulted in hepatic decompensation; serum HBV DNA level was the only significant risk factor (P = .003). The area under the receiver operating characteristic curve was 88.6% (P < .001). A serum HBV DNA cut-off value of 1.55 x 10(9) copies/mL predicted decompensation with a sensitivity of 85.7%, a specificity of 85.5%, a negative prediction value of 99.1%, and positive prediction value of 24.0%.

CONCLUSIONS

During acute exacerbation of HBeAg-positive chronic hepatitis B, a serum HBV DNA cut-off value of 1.55 x 10(9) copies/mL can be used to identify patients in need of immediate antiviral therapy.

Pregnant women with chronic hepatitis B: an analysis of 55 cases

AIM: To analyze the clinical and pathological characteristics of chronic hepatitis B in pregnancy and to explore the relationship between pregnancy and hepatitis B virus (HBV) infection.

METHODS: The clinical data of 55 pregnant women with chronic hepatitis B were retrospectively analyzed and compared with those of pregnant HBV carriers and normal pregnant women. The clinical and pathological characteristics of chronic hepatitis B in pregnancy were then analyzed.

RESULTS: The morbility of hepatitis increased gradually with the increase in pregnancy duration. Compared with pregnant HBV carriers, ALT, AST, TBIL and DBIL significantly increased (210.2 U/L ± 144.7 U/L vs 22.7 U/L ± 11.6 U/L, 197.3 U/L ± 113.8 U/L vs 19.1 U/L ± 14.9 U/L, 64.9 μmol/L ± 37.8 μmol/L vs 6.8 μmol/L ± 5.8 μmol/L, and 44.2 μmol/L ± 23.8 μmol/L vs 4.8 μmol/L ± 2.2 μmol/L, respectively; all P < 0.05), and albumin and PTA decreased significantly (31.3 G/L ± 7.3 G/L vs 35.8 G/L ± 4.7 G/L; 66.4% ± 8.6% vs 82.1% ± 8.7%, both P < 0.05) in pregnant women with chronic hepatitis B. The rates of HBeAg positivity and high HBV DNA load were especially higher in pregnant women with chronic hepatitis B than in other groups of subjects.

CONCLUSION: HBV infection in pregnant women occurs mainly during the middle to late stages of pregnancy. Many cases of chronic hepatitis B in pregnancy are serious. HBeAg positivity and high HBV DNA load could be used as parameters for predicting the occurrence of HBV infection.