Serum hepatitis B surface antigen quantitation can reflect hepatitis B virus in the liver and predict treatment response

Changes in the serum level of hepatitis B virus (HBV) surface antigen over the natural course of HBV infection

BACKGROUND

Despite its status as a potential biomarker of hepatitis B virus (HBV) response to interferon treatment, the changes in hepatitis B surface antigen (HBsAg) levels over the natural course of HBV carriers have not been analyzed sufficiently.

METHODS

A total of 101 HBV carriers were followed prospectively from 1999 to 2009. HBsAg level was measured yearly during the followed period.

RESULTS

HBsAg levels at baseline ranged from -1.4 to 5.32 log IU/ml, with a median value of 3.2 log IU/ml. Lower HBsAg levels were significantly associated with higher age and lower HBV replication status. The rate of change of HBsAg levels showed two peaks, with a cut-off value of -0.4 log IU/year. Based on this, patients were tentatively classified into rapid decrease (rate of change <-0.4 log IU/year) and non-rapid decrease groups. All baseline levels of HBsAg, HB core-related Ag, and HBV DNA were lower in the rapid decrease group than in the non-rapid decrease group. Patients with persistently positive HBeAg were all classified into the non-rapid decrease group. In patients with persistently negative HBeAg, HBV DNA levels were significantly (P = 0.028) lower in the rapid decrease group than in the non-rapid decrease group.

CONCLUSIONS

Lower baseline HBsAg levels were significantly associated with older age and lower viral activity. Both a loss of HBeAg detection as well as inactive replication of HBV are suggested to be fundamental factors contributing to a rapid decrease in HBsAg over the natural course of HBV infection.

Combination therapy with peginterferonα-2a and adefovir dipivoxil for HBeAg-positive chronic hepatitis B: A prospective multicenter cohort study

AIM: To analyze the efficacy and safety of adefovir dipivoxil (ADV) as an add-on therapy in patients with HBeAg-positive chronic hepatitis B (CHB) who have a suboptimal response to peginterferonα-2a (Peg-IFNα-2a) treatment for 48 weeks, and to evaluate the predictors of response to the combination therapy.

METHODS: Ninety HBeAg-positive CHB patients who had been being treated with Peg-IFNα-2a for 24 weeks and had HBV DNA ≥ 2.0 × 10³ IU/mL and HBV DNA decrease ≥ 2 log10 IU/mL were randomly assigned either to add on ADV (group A1, 45 patients) or to continue Peg-IFNα-2a monotherapy (group A2, 45 patients).Other 55 patients with HBV DNA < 2.0 × 10³ IU/mL were assigned to continue Peg-IFNα-2a monotherapy. The levels of HBV DNA, HBsAg, HBeAg and ALT at baseline and during treatment were compared among the three groups.

RESULTS: The rates of undetectable serum HBV DNA at weeks 36 and 48 were highest in group B, followed by group A1 and group A2 (P < 0.01). HBV DNA level at week 36 declined more significantly in group B than in group A1, and in group A1 than in group A2 (both P < 0.01). At week 48, HBV DNA level declined more significantly in groups A1 than in group A2 (P < 0.01), while there was no significant difference between group A1 and B. Rates of HBeAg loss and HBeAg seroconversion in groups A1, A2 and B were not statistically different at weeks 36 and 48. Amplitude of HBeAg seroconversion rate from week 24 to week 48 in group A1 was higher than those in group A2 and group B (both P < 0.01). There were 4, 1 and 2 cases of HBsAg reduction in group A1, group A2 and group B at week 48, respectively. Rates of ALT normalization in group A1, group A2 and group B were not statistically different at weeks 36 and 48. All the patients finished 48-week therapy without severe adverse effects. Rate of undetectable serum HBV DNA in group A1 was only associated with the amplitude of HBV DNA level at week 36. HBV DNA reduction levels at week 36 from baseline or week 24 could predict undetectable serum HBV DNA at week 48 with a PPV of 90.5% and 95.7%, respectively.

CONCLUSION: ADV as an add-on therapy in patients with HBeAg-positive CHB who have a suboptimal response to Peg-IFNα-2a treatment for 48 weeks could improve HBeAg seroconversion rate and undetectable HBV DNA rate with tolerable adverse effects. HBV DNA reduction levels at week 36 from baseline or week 24 could predict the viral response to the combination therapy at week 48.

Hepatitis B surface antigen declines and clearance during long-term tenofovir therapy in patients coinfected with HBV and HIV

BACKGROUND

The kinetics of hepatitis B surface antigen (HBsAg) are predictive in HBV-infected patients treated with pegylated interferon. Knowledge about the value of HBsAg levels in patients coinfected with HBV and human immunodeficiency virus (HIV) is lacking.

METHODS

We quantified serum HBsAg in a Dutch multicenter cohort of 104 patients coinfected with HIV and HBV who were treated with tenofovir disoproxil fumarate (TDF) as part of highly active antiretroviral therapy. The median duration of therapy was 57 months (interquartile range, 34-72 months).

RESULTS

Hepatitis B e antigen (HBeAg)-positive patients achieved a decline of 2.2 log IU/mL in HBsAg, whereas HBeAg-negative patients only achieved a decline of 0.6 log IU/mL during 6 years of TDF therapy. Declines in HBsAg at months 6 and 12 correlated with CD4 cell count for HBeAg-positive patients. Five HBeAg-positive patients (8%) and 3 HBeAg-negative patients (8%) cleared HBsAg. HBeAg-negative patients who cleared HBsAg had lower baseline HBsAg as compared to patients who remained HBsAg positive. The majority of patients who cleared HBsAg achieved this end point within the first year. In HBeAg-positive patients, decline in HBsAg at month 6 was predictive of achieving HBsAg seroclearance.

CONCLUSIONS

Receipt of TDF therapy by HIV/HBV-coinfected patients for up to 6 years led to a significant decrease in HBsAg in the HBeAg-positive population. HBsAg kinetics early during treatment were predictive of HBsAg seroclearance and correlated with an increased CD4 cell count, underlining the importance of immune restoration in HBV clearance.

Prediction of off-treatment response to lamivudine by serum hepatitis B surface antigen quantification in hepatitis B e antigen-negative patients

BACKGROUND

The timing of antiviral therapy cessation in hepatitis B e antigen (HBeAg)-negative patients is controversial. Here, we aimed to investigate the role of HBV DNA and hepatitis B surface antigen (HBsAg) monitoring to predict off-treatment sustained response.

METHODS

A total of 53 HBeAg-negative chronic hepatitis B patients who received lamivudine for 34 ±23 (range 12-76) months and had lamivudine stopped for 47 ±35 months were studied. Primary outcome was sustained response, defined as HBV DNA≤200 IU/ml, at 12 months post-treatment (SR-12).

RESULTS

A total of 9 (17%) patients achieved SR-12. HBV DNA at baseline, month 6 and end of treatment had no association with SR-12. HBsAg levels tended to decrease more significantly during treatment among SR-12 responders. At the end of treatment, both HBsAg ≤2 log IU/ml and reduction by >1 log from baseline had sensitivity, specificity, positive and negative predictive values for SR-12 of 78%, 96%, 78% and 96%, respectively. All 5 patients with HBsAg≤2 log IU/ml and reduction >1 log at the end of treatment achieved SR-12 and all 40 patients with HBsAg>2 log IU/ml and reduction ≤1 log did not have SR-12. The cumulative probability of sustained response and HBsAg clearance at 5 years among patients with HBsAg≤2 log IU/ml were 88% and 72%, respectively, that among patients with HBsAg reduction >1 log were 74% and 61%, respectively.

CONCLUSIONS

Monitoring of HBsAg level can guide the timing of stopping lamivudine in HBeAg-negative chronic hepatitis B.

Significance of HBV cccDNA and clinical factors in evaluating prognosis of hepatocelluar carcinoma following surgical resection

AIM: To investigate the correlation of HBV cccDNA and clinical factors with the survival of patients with hepatocellular carcinoma (HCC) after hepatectomy.

METHODS: A retrospective analysis was carried out in 60 HCC patients who underwent radical operation from 2003 to 2006 at our hospital. Serum HBV DNA and covalently closed circular DNA (cccDNA) levels were detected by real-time PCR. In 55 patients with complete follow-up data, serum HBV DNA, cccDNA in liver tissue and clinical characteristics were retrospectively analyzed. The overall survival and recurrence-free survival (RFS) were calculated using the Kaplan-Meier method. All the data were analyzed using Log-rank test and Cox regression model.

RESULTS: HBV cccDNA was positive in only one serum sample (1/35) and in 20% (11/55) of tumor tissues. There was a significant correlation between intrahepatic cccDNA in tumor tissue and total HBV DNA in serum (r = 0.364, P = 0.006). The 1-, 3-, 5-year overall survival and RFS rates for 55 patients after HCC resection were 73%, 51% and 38%, and 63%, 29% and 19%, respectively. The independent prognostic factor influencing RFS was the level of intrahepatic cccDNA in tumor tissue. The independent prognostic factors influencing overall survival were tumor numbers and vessel invasion.

CONCLUSION: HCC patients with solitary tumor and without vessel invasion showed a higher overall survival. HCC patients with an intrahepatic HBV cccDNA level of less than 1 000 copies/μg had a higher RFS.

Comparison of serum HBsAg quantitation by four immunoassays, and relationships of HBsAg level with HBV replication and HBV genotypes

Background

The decline in hepatitis B virus surface antigen (HBsAg) may be an early predictor of the viral efficacy of Hepatitis B virus (HBV) therapy. The HBsAg levels obtained by different immunoassays now need comparing and the relationships between levels of HBsAg and HBV DNA alongside HBsAg and genotype must be evaluated.

Methodology/Principal Findings

HBsAg levels were compared among 80 patients using the Abbott Architect assay, a commercial immunoassay approved for HBsAg detection and quantitation, and three other assays derived from immunoassays approved for HBsAg detection (manufactured by Diasorin, Bio-Rad and Roche). Good correlation was found between the Abbot vs. Diasorin, Bio-Rad and Roche assays with narrow 95% limits of agreement and small mean differences: −0.06 to 0.11, −0.09 log₁₀ IU/mL; −0.57 to 0.64, −0.04 log₁₀ IU/mL; −0.09 to 0.45, −0.27 log₁₀ IU/mL, respectively. These agreements were not affected by genotypes A or D. HBsAg was weakly correlated with HBV DNA, whatever the HBsAg assay used: Abbott, ρ = 0.36 p = 0.001, Diasorin ρ = 0.34, p = 0.002; Bio-Rad ρ = 0.37, p<0.001; or Roche ρ = 0.41, p<0.001. This relationship between levels of HBsAg and HBV DNA seemed to depend on genotypes. Whereas HBsAg (Abbott assay) tended to correlate with HBV DNA for genotype A (ρ = 0.44, p = 0.02), no such correlation was significant for genotypes D (ρ = 0.29, p = 0.15).

Conclusion/Significance

The quantitation of HBsAg in routine clinical samples is comparable between the reference assay and the adapted assays with acceptable accuracy limits, low levels of variability and minimum discrepancy. While HBsAg quantitation is not affected by HBV genotype, the observed association between levels of HBsAg and HBV DNA seems genotype dependent.

Hepatitis B surface antigen seroconversion is associated with favourable long-term clinical outcomes during lamivudine treatment in HBeAg-negative chronic hepatitis B patients

The aims of this study were to assess hepatitis B surface antigen (HBsAg) seroconversion and to determine its impact on the natural course of the disease in patients with HBeAg-negative chronic hepatitis B (CHB) during lamivudine (LMV) treatment. A total of 183 consecutive patients with HBeAg-negative CHB who were treated with LMV were included in the study. Data were retrospectively collected from outpatient visit charts. The primary endpoint was HBsAg seroconversion to anti-HBs. The secondary endpoint was to determine the development of cirrhosis. Loss of HBsAg was confirmed in 10 patients and seroconversion to anti-HBs in nine patients during LMV treatment or after its discontinuation. HBsAg seroconversion was achieved on-treatment in four patients after a median treatment duration of 30 months and off-treatment in the remaining five patients in a median 61 months after LMV discontinuation. The cumulative probability of HBsAg seroconversion increased from 0.6% at 1 year and 1.9% at 5 years to 21.5% at 10 years of LMV during and after LMV treatment. HBsAg clearance was preceded by undetectable serum hepatitis B virus (HBV) DNA. The majority of the patients responding to treatment had undetectable HBV DNA levels at 24 weeks of treatment. The cumulative probability of LMV resistance increased from 2.2% at 1 year to 37.3% at 5 years. No baseline parameter predicting either HBsAg seroconversion or the emergence of LMV resistance was identified. None of the patients with HBsAg seroconversion experienced virological breakthrough or disease progression during the follow-up period. These results indicate that HBsAg seroclearance can occur in patients with HBeAg-negative CHB under LMV therapy and predicts better clinical outcome.

Durable hepatitis B surface antigen decline in hepatitis B e antigen-positive chronic hepatitis B patients treated with pegylated interferon-α2b: relation to response and HBV genotype

BACKGROUND

On-treatment decline of serum hepatitis B surface antigen (HBsAg) may reflect the immunomodulatory effect of pegylated interferon (PEG-IFN) for hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB). We compared HBsAg decline across HBV genotypes between combined responders (HBeAg loss and HBV DNA<10,000 copies/ml at week 78), HBeAg responders (HBeAg loss with HBV DNA>10,000 copies/ml) and non-responders.

METHODS

HBsAg was measured at baseline, on-treatment and 6 months post-treatment in 221 HBeAg-positive CHB patients treated with PEG-IFN with or without lamivudine for 52 weeks, and in a representative subgroup of 142 patients at long-term follow-up (LTFU; mean 3.0 years).

RESULTS

On-treatment HBsAg decline significantly varied according to HBV genotype (A and B more than C and D; P<0.001). On-treatment HBsAg decline also differed between patients with a combined response (n=43) and those without (n=178; 3.34 versus 0.69 log IU/ml decline at week 52; P<0.001). Among patients without a combined response, no difference was observed between HBeAg responders (n=41) versus non-responders (n=137). HBsAg decline was sustained in combined responders and progressed to 3.75 log IU/ml at LTFU. Patients with a combined response achieved pronounced HBsAg declines, irrespective of HBV genotype, and those who achieved HBsAg levels <1,000 IU/ml at week 78 had a high probability of a sustained response and HBsAg clearance through LTFU.

CONCLUSIONS

On-treatment HBsAg decline during PEG-IFN therapy for HBeAg-positive CHB depends upon HBV genotype. Patients with a combined response to PEG-IFN achieve a pronounced HBsAg decline, irrespective of HBV genotype, which is sustained through 3 years of off-treatment follow-up.

Serum hepatitis B surface antigen levels in the natural history of chronic hepatitis B infection

BACKGROUND  The production of hepatitis B surface antigen (HBsAg) may evolve during long-lasting virus-host interactions in chronic hepatitis B (CHB). The impact of age on HBsAg production remains unclear. AIM  To determine the age-specific distribution patterns of HBsAg and related factors during the natural course of CHB infection. METHODS  Seven hundred and sixty-eight untreated HBsAg carriers were enrolled in the study. The parameters and distribution patterns of HBsAg were evaluated in relation to age and immune phases. RESULTS  The HBsAg levels were significantly lower in the HBeAg-negative stage, with the lowest levels in inactive carriers. The HBsAg tended to decrease from hepatitis to cirrhosis and to hepatocellular carcinoma, and from Child-Pugh class A to B and to C. Age and HBV DNA were independently associated with HBsAg levels. In HBeAg-positive patients, the HBsAg levels were distributed in a triphasic-like decline pattern by 2 logs across age strata. For HBeAg-negative patients, the titres in inactive carriers exhibited a 2-log reduction, but remained unchanged over age strata in patients with HBeAg-negative hepatitis. The ratios of HBsAg/HBV-DNA were highest, but steadily decreased with age in inactive carriers, whereas the levels remained largely unchanged over the entire age strata in patients with HBeAg-negative hepatitis. CONCLUSIONS  Age and HBV DNA levels are independent parameters of HBsAg levels. During the natural course of CHB infection, HBsAg levels decrease with age and disease progression, but the patterns are significantly different between the immune phases of CHB. This information may contribute to our understanding of the immunopathogenesis of chronic hepatitis B and management involving HBsAg quantification.

Hepatitis B surface antigen quantification: why and how to use it in 2011 - a core group report

Quantitative HBsAg had been suggested to be helpful in management of HBV, but assays were cumbersome. The recent availability of commercial quantitative assays has restarted the interest in quantitative serum hepatitis B surface antigen (HBsAg) as a biomarker for prognosis and treatment response in chronic hepatitis B. HBsAg level reflects the transcriptional activity of cccDNA rather than the absolute amount of cccDNA copies. Serum HBsAg level tends to be higher in hepatitis B e antigen (HBeAg)-positive than HBeAg-negative patients. Among patients with a low HBV DNA (<2000IU/ml), HBsAg <1000IU/ml in genotype D HBV infection and HBsAg <100IU/ml in genotype B/C HBV infection is associated with inactive carrier state in HBeAg-negative patients. The HBsAg reduction by nucleos(t)ide analogues (NA) is not as pronounced as by interferon treatment. On peginterferon treatment, sustained responders tend to show greater HBsAg decline than the non-responders. The optimal on-treatment HBsAg cutoff to predict response needs further evaluation in HBeAg-positive patients, but an absence of HBsAg decline together with a <2 log reduction in HBV DNA at week 12 can serve as stopping rule in HBeAg-negative patients with genotype D HBV infection. A rapid serum HBsAg decline during NA therapy may identify patients who will clear HBsAg in the long-term. There are early reports among Asian patients that an HBsAg level of <100IU/ml might predict lower risk of relapse after stopping NA treatment. In clinical practice, serum HBsAg level should be used together with, but not as a substitute for, HBV DNA.

Quantitative hepatitis B surface antigen levels in patients with chronic hepatitis B after 2 years of entecavir treatment

OBJECTIVES

The role of quantitative hepatitis B surface antigen (HBsAg) levels in patients receiving oral antiviral therapy is controversial. We aimed to determine the HBsAg response in chronic hepatitis B patients treated with entecavir 0.5 mg daily for 2 years.

METHODS

A total of 166 patients were included. Liver biochemistry, hepatitis B virus (HBV) serological markers, HBV DNA, and quantitative HBsAg levels were performed at baseline, year 1, and year 2 after commencing entecavir. Additional HBsAg levels were measured at 12 and 24 weeks in patients with available sera.

RESULTS

In all, 68 patients were hepatitis B e-antigen (HBeAg) positive. Age, HBV DNA, and alanine aminotransferase (ALT) were significantly correlated with HBsAg levels at baseline (r=-0.429, 0.607, and 0.254, respectively, all P<0.05). The correlation with HBV DNA and ALT levels was reduced by entecavir treatment, and was lost after 2 years of treatment. There was an overall decline in HBsAg levels from baseline to year 1 to year 2 (3,377.4 vs. 2,316.5 vs. 1,903.0 IU/ml, respectively, P<0.001). However, at year 2, 102 patients (61%) had no significant changes (<0.5 log difference), 50 (30%) had significant decline (≥0.5 log decrease), whereas 14 (9%) had significant increase (≥0.5 log increase). Of the patients, 151 (91%) had undetectable HBV DNA; 25 (37%) underwent HBeAg seroconversion. Neither HBsAg at baseline nor early decline at weeks 12 or 24 was predictive of HBeAg seroconversion at 2 years.

CONCLUSIONS

Despite HBV DNA suppression, the majority did not show significant decline in HBsAg levels. Early decline of HBsAg levels at 12/24 weeks was not associated with HBV DNA suppression or HBeAg seroconversion.

Editorial: Measurement of HBsAg concentration during antiviral therapy of hepatitis B: who, when, and why

The measurement of hepatitis B surface antigen (HBsAg) concentration in serum is now under evaluation in treatment trials for hepatitis B. HBsAg kinetics differ during interferon and nucleoside analog treatment. A rapid decline in HBsAg concentration during interferon therapy has been associated with a higher chance for sustained virological response. By contrast, a much slower decline often occurs during nucleoside analog therapy and limits the ability of this test to be a useful prognostic indicator during the first year or two of treatment.

Clinical importance of serum hepatitis B surface antigen levels in chronic hepatitis B

Quantitative serology for hepatitis B surface antigen (HBsAg) is a new candidate marker for prediction of clinical outcome. The aim of this study was to investigate the clinical significance of quantifying HBsAg in patients with hepatitis B virus (HBV) infection. A total of 424 patients who tested positive for HBsAg and were referred to Chiba University Hospital between January 1985 and April 2008 were included in the study, and the following characteristics were analyzed: age, gender, status of hepatitis B e antigen (HBeAg), alanine aminotransferase level (ALT), HBV DNA level, number of platelets and development of hepatocellular carcinoma. Measurement of HBsAg was performed using the chemiluminescent enzyme immunoassay method. The study group consisted of 239 men and 185 women, and their average age was 40.6 ± 14.0 years. HBsAg showed a positive correlation with HBV DNA level (Pearson's product moment correlation, r = 0.586, P < 0.001) and a weak inverse correlation with age (r = 0.3325, P < 0.001). A control study, matched with age and sex, was performed between two groups with and without HBeAg seroconversion during follow-up period. Compared with the age and sex-matched controls, the change in HBsAg levels per year showed a significant decrease 2 years before seroconversion (paired t-test, P < 0.05). The serial measurement of quantitative HBsAg level has the possibility of predicting the occurrence of HBeAg seroconversion.

Serum hepatitis B surface antigen monitoring in long-term lamivudine-treated hepatitis B virus patients

Serum hepatitis B virus surface antigen (HBsAg) levels have been suggested to predict interferon response in chronic hepatitis B. A few data are available on the role of HBsAg measurement in nucleos(t)ide analogues (NA) treatment. We retrospectively investigated the relation between HBsAg changes and main treatment outcomes during long-term lamivudine treatment in hepatitis e antigen (HBeAg)-negative chronic hepatitis B. A total of 42 HBeAg-negative patients were consecutively enrolled in an open-label study on long-term lamivudine monotherapy (150 mg/die). Serum HBsAg levels were quantified every 6 months by Architect assay (Abbott Diagnostics). HBV-DNA was quantified quarterly by real-time PCR (Roche Diagnostics). The median duration of lamivudine treatment was 66 months (20-153). One patient (2%) was a primary nonresponder, 35 (83%) developed virological breakthrough (VB) and the remaining six patients (14%) were classified as long-term on-treatment responders. During treatment, HBsAg levels decreased only in long-term on-treatment responders, while no changes were observed in resistant patients. Failure to achieve a decrease of 0.7 log(10) IU/mL in serum HBsAg at month six of lamivudine had a positive predictive value of developing VB of 90% and a negative predictive value of 100%. These high predictive values were also maintained in the subgroup of patients negative for HBV-DNA at month six. The results of this study with a small sample size suggest a role of on-treatment HBsAg quantification in the management of lamivudine-treated patients. If validated prospectively in a larger patient cohort, HBsAg measurements would be a useful adjunct to optimize antiviral therapy.

Intrahepatic response markers in chronic hepatitis B patients treated with peginterferon alpha-2a and adefovir

BACKGROUND AND AIM

We investigated whether intrahepatic markers could predict response in chronic hepatitis B virus (HBV) patients treated with peg-interferon and adefovir for 48 weeks.

METHODS

Intrahepatic covalently closed circular DNA (cccDNA), total intrahepatic HBV DNA and the proportion of hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) positive hepatocytes in 16 hepatitis B e antigen (HBeAg) positive and 24 HBeAg negative patients were measured at baseline and at end of treatment.

RESULTS

Baseline intrahepatic markers were not associated with sustained virological response (SVR) defined as HBV DNA < 2000 IU/mL and persistent normal alanine aminotransferase levels at the end of follow-up (week 72). At end of treatment, intrahepatic cccDNA and total intrahepatic HBV DNA in HBeAg positive patients were significantly lower in patients with HBeAg seroconversion (P = 0.016 and P = 0.010) with positive predictive values (PPV) for SVR of 80% and 80%, respectively. In HBeAg negative patients, intrahepatic cccDNA and total intrahepatic HBV DNA had declined significantly at end of treatment (P = 0.035 and P = 0.041) and corresponding PPV for SVR was 73% and 82%. In HBeAg positive patients, median proportion of HBcAg positive hepatocytes declined significantly (P = 0.002) at end of treatment. In HBeAg negative patients, the proportion of HBsAg positive hepatocytes had declined significantly at end of treatment (P = 0.0009). Using HBsAg ≤ 7.5% as a limit, PPV for SVR in HBeAg negative patients was 83%.

CONCLUSIONS

At end of treatment in HBeAg positive patients, intrahepatic cccDNA and total intrahepatic HBV DNA were predictive for SVR. In HBeAg negative patients a proportion of < 7.5% HBsAg positive hepatocytes at end of treatment was a strong predictor for SVR.

Viral determinants of hepatitis B surface antigen seroclearance in hepatitis B e antigen-negative chronic hepatitis B patients

BACKGROUND

We studied whether quantification of serum HBsAg and HBV DNA levels could predict spontaneous HBsAg clearance in patients with negative hepatitis B e antigen (HBeAg).

METHODS

Serum HBsAg and HBV DNA levels were measured at baseline among a longitudinal cohort of 103 HBeAg-negative patients recruited since 1997.

RESULTS

Twelve (12%) patients developed HBsAg seroclearance after 88 ± 26 months (range, 21-139) of follow-up. At baseline, the serum HBsAg level among patients who cleared HBsAg (1.30 ± 1.27 log IU/mL) was significantly lower than those who did not clear HBsAg (2.96 ± 0.84 log IU/mL; P < .001). The area under receiver operating characteristics (ROC) curve for serum HBsAg to predict HBsAg seroclearance was 0.90 (95% confidence interval [CI], 0.83-0.97; P < .001). Nine (75%) of 12 patients who had HBsAg seroclearance versus 8 (9%) of 91 who remained HBsAg-positive had serum HBsAg ≤100 IU/mL at the baseline (P < .001). An HBsAg cutoff of ≤100 IU/mL had 75% sensitivity and 91% specificity to predict HBsAg seroclearance. Baseline serum HBV DNA could not predict HBsAg seroclearance; the area under ROC curve was 0.64 (95% CI, 0.46-0.81; P = .13).

CONCLUSIONS

Single-point serum HBsAg level can predict the chance of HBsAg seroclearance in chronic hepatitis B patients with negative HBeAg.

Clinical utility of hepatitis B surface antigen quantitation in patients with chronic hepatitis B: a review

This clinically relevant review focuses on recent findings concerning hepatitis B surface antigen (HBsAg) quantitation in untreated patients and treated patients with chronic hepatitis B. Recent studies and emerging data have shown that both HBsAg and hepatitis B virus (HBV) DNA levels decline during the natural course of a chronic HBV infection; they are lowest in the inactive phase, which is also characterized by the highest HBsAg/HBV DNA ratio. It has been demonstrated that the combined use of HBsAg and HBV DNA levels might help in the identification of true inactive carriers with high accuracy. Retrospective analyses of HBsAg levels in patients undergoing therapy have suggested a role for HBsAg quantitation in monitoring the response to therapy. In comparison with nucleos(t)ide analogues (NAs), interferon-based therapy results in greater overall declines in serum HBsAg levels. A rapid on-treatment decline in HBsAg levels appears to be predictive of a sustained response. With the aid of HBsAg quantitation, it appears that we can anticipate an individualized approach to tailoring the treatment duration. The proposal of early stopping rules for patients not responding to pegylated interferon (according to a lack of any HBsAg decline) represents a step toward a response-guided approach. The development of stopping rules for patients treated with NAs is desirable for reducing the need for lifelong therapy. However, before stopping rules for antiviral therapy can be applied, we need to learn more about the kinetics of HBsAg declines during the natural history of the infection and as a response to therapy so that we can better define the best timing, the relevant HBsAg cutoff levels, and the best ways to apply these rules in clinical practice.

Serum hepatitis B surface antigen levels predict surface antigen loss in hepatitis B e antigen seroconverters

BACKGROUND & AIMS

Loss of hepatitis B surface antigen (HBsAg) usually indicates that hepatitis B virus (HBV) infection has been cured. However, little is known about factors predicting HBsAg loss in patients who spontaneously clear hepatitis B e antigen (HBeAg).

METHODS

We studied 390 Taiwanese HBeAg-positive patients with chronic hepatitis who had spontaneously cleared HBeAg (seroconversion) during follow-up. Serum levels of HBV DNA and HBsAg were determined 1 year after HBeAg seroconversion, and their relationships with subsequent HBsAg loss were investigated.

RESULTS

In a mean follow-up of 7.4 years, the average annual rate of HBsAg loss was 0.62%. Serum levels of HBsAg and HBV DNA were inversely associated with HBsAg loss in a dose-response manner. Compared with patients with HBsAg levels ≥1000 IU/mL, the HBsAg loss rate was higher for those with HBsAg levels of 100 to 999 and <100 IU/mL, with hazard ratios of 4.4 (95% confidence interval, 1.1-17.0) and 24.3 (8.7-67.5), respectively. Among those who underwent HBsAg loss within 6 years of follow-up, serum HBsAg levels were a better predictor than HBV DNA levels by receiver operating characteristic curve analysis (area under the receiver operating characteristic curve, 0.90 vs 0.69; P = .012); an HBsAg level <100 IU/mL predicted HBsAg loss within 6 years with a diagnostic accuracy of 91.5%, sensitivity of 83.3%, specificity of 92.1%, positive predictive value of 45.5%, and negative predictive value of 98.6% in patients with an HBV DNA level <200 IU/mL.

CONCLUSIONS

Low serum levels of HBsAg, alone or in combination with HBV DNA levels, 1 year after HBeAg seroconversion can predict HBsAg loss in patients with HBV genotype B or C infection.

Predictors of relapse in chronic hepatitis B after discontinuation of anti-viral therapy

BACKGROUND

Optimal duration of anti-viral therapy in chronic hepatitis B virus (HBV) infection remains unclear.

AIM

To investigate factors that could predict relapse after stopping anti-viral agents.

METHODS

Chronic hepatitis B patients who were treated with anti-viral agents (lamivudine, adefovir, entecavir) and have stopped the treatment were recruited. Anti-viral agents were stopped according to the recommendations of the Asian Pacific Association for the Study of the Liver. Virological relapse was defined as an increase in serum HBV DNA to >1000 copies/mL after discontinuation of treatment.

RESULTS

Eighty-four (69 treatment naïve and 15 lamivudine resistant) patients were eligible for this study. Thirty-seven patients developed virological relapse at 4.3 ± 2.9 (range 1-11) months after discontinuation of therapy. The 1-year cumulative probability of virological relapse was 42% and 47% in HBeAg (hepatitis B e antigen)-positive (n = 41) and HBeAg (hepatitis B e antigen)-negative (n = 43) patients, respectively. On multivariate analysis by Cox proportional hazard model, pre-existing lamivudine resistance, delayed suppression of HBV DNA to undetectable level during anti-viral therapy and to a higher HBsAg (hepatitis B surface antigen) level at the end of treatment were associated with virological relapse. Twelve of the 15 (80%) lamivudine resistant patients developed virological relapse. Among the 11 treatment naïve patients who had HBsAg ≤ 2 log IU/mL at the end of treatment, 1 (9%) of them had virological relapse.

CONCLUSIONS

Treatment cessation among lamivudine resistant patients is associated with high risk of virological relapse. Serum HBsAg level at the end of treatment and rate of HBV DNA suppression can provide supplementary information to guide the timing of stopping anti-viral drugs.

The G1613A mutation in the HBV genome affects HBeAg expression and viral replication through altered core promoter activity

Infection of hepatitis B virus (HBV) causes acute and chronic hepatitis and is closely associated with the development of cirrhosis and hepatocellular carcinoma (HCC). Previously, we demonstrated that the G1613A mutation in the HBV negative regulatory element (NRE) is a hotspot mutation in HCC patients. In this study, we further investigated the functional consequences of this mutation in the context of the full length HBV genome and its replication. We showed that the G1613A mutation significantly suppresses the secretion of e antigen (HBeAg) and enhances the synthesis of viral DNA, which is in consistence to our clinical result that the G1613A mutation associates with high viral load in chronic HBV carriers. To further investigate the molecular mechanism of the mutation, we performed the electrophoretic mobility shift assay with the recombinant RFX1 protein, a trans-activator that was shown to interact with the NRE of HBV. Intriguingly, RFX1 binds to the G1613A mutant with higher affinity than the wild-type sequence, indicating that the mutation possesses the trans-activating effect to the core promoter via NRE. The trans-activating effect was further validated by the enhancement of the core promoter activity after overexpression of RFX1 in liver cell line. In summary, our results suggest the functional consequences of the hotspot G1613A mutation found in HBV. We also provide a possible molecular mechanism of this hotspot mutation to the increased viral load of HBV carriers, which increases the risk to HCC.

Hepatitis B surface antigen: relation to hepatitis B replication parameters in HBeAg-negative chronic hepatitis B

BACKGROUND & AIMS

Translation of HBsAg depends on transcription of the appropriate mRNAs from cccDNA, but its relation to other hepatitis B virus (HBV) replication parameters is not known, inasmuch as integrated sequences of HBV-DNA may also contribute to its serum levels, especially in HBeAg-negative chronic hepatitis B (CHB) patients.

METHODS

We investigated HBsAg serum levels, its hepatocellular expression, and their relationship to HBV replicative- and host-response parameters before treatment in 54 HBeAg-negative CHB patients and in 15 of them after 40.1±33.3months of virological response on oral antiviral (NUC) therapy also. Liver cccDNA and HBV-DNA quantitation, HBsAg- and HBcAg-immunostaining were performed in the same needle biopsy material, while serum HBsAg and HBV-DNA levels were measured in samples drawn on the day of liver biopsy.

RESULTS

In untreated patients, serum HBsAg correlated positively with HBsAg-positive hepatocytes/mm(2) (p=0.003) and weakly with serum HBV-DNA, but not with cccDNA, liver HBV-DNA, HBcAg-positive hepatocytes/mm(2), or ALT. cccDNA correlated significantly with liver HBV-DNA (p<0.00001), ALT (p=0.001), and serum HBV-DNA levels (p=0.012) but not with liver HBsAg or HBcAg. Antiviral therapy decreased serum HBsAg levels by 79.6% (p=0.012) and liver HBV-DNA by 84.4% (p=0.026) in paired comparisons and, as expected, significantly decreased serum HBV-DNA and ALT levels, but not cccDNA.

CONCLUSIONS

In untreated HBeAg-negative CHB, serum HBsAg levels reflect liver HBsAg, but not cccDNA or liver HBV-DNA, suggesting that they are not solely dependent on the replicative cycle of HBV. Effective NUC therapy for 3.34 years significantly lowers serum HBsAg and liver HBV-DNA, but not cccDNA.

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.

Hepatitis B surface antigen monitoring and management of chronic hepatitis B

Serum hepatitis B surface antigen (HBsAg) levels reflect intrahepatic hepatitis B virus (HBV) covalently closed circular DNA and may be a valuable addition to HBV DNA in the management of patients with chronic hepatitis B (CHB). Among HBeAg-negative CHB patients with low HBV DNA levels, HBsAg quantification may help distinguish those with active CHB from true inactive carriers with a very favourable prognosis, thus limiting the need for long-term intensive monitoring of ALT and HBV DNA levels. In patients treated with peginterferon (PEG-IFN), achievement of a decline in HBsAg during therapy appears to be an important marker for treatment outcome, and several groups have proposed stopping rules based on HBsAg thresholds. A recently described stopping rule incorporating a combination of HBsAg and HBV DNA levels can accurately identify HBeAg-negative patients, especially those with HBV genotype D, not responding to PEG-IFN. Current applications of HBsAg levels in the monitoring of patients treated with nucleo(s)tide analogues are still being evaluated. First data from these studies show that HBsAg decline, and thus subsequent clearance, is confined to those with an active immune response to HBV, such as HBeAg-positive patients with elevated ALT, or those who achieve HBeAg clearance.

Quantitation of HBV covalently closed circular DNA in micro formalin fixed paraffin-embedded liver tissue using rolling circle amplification in combination with real-time PCR

BACKGROUND

The study aimed to develop an effective method to quantitate HBV covalently closed circular DNA (cccDNA) using small section of formalin fixed paraffin-embedded (FFPE) liver biopsy.

METHODS

Plasmid-safe ATP-dependent DNase (PSAD)-treated samples were subjected to rolling circle amplification (RCA) prior to real-time PCR mediated by cccDNA-selective primers. Human beta-actin gene was used as a reference control.

RESULTS

Compared to the classical method, i.e., PSAD digestion+real-time PCR, introduction of RCA increased the lower limit of detection for about 2 logs with good inter- and intra-assay reproducibility. HBV cccDNA was detected in 91.5% (119/130) of the FFPE samples. The cccDNA levels (copy/cell) between FFPE liver tissues and fresh frozen counterpart tissues were comparable. The median of cccDNA level in HBeAg-positive patients was higher than that in HBeAg-negative ones (52.60 vs. 31.25copies/cell, P<0.01). Intrahepatic cccDNA level was positively correlated with intrahepatic HBV total DNA level, but not obviously correlated with serum HBV DNA or alanine aminotransferase levels.

CONCLUSIONS

The method could sensitively and specifically quantitate intrahepatic HBV cccDNA in micro FFPE liver biopsy tissue for evaluation of HBV replication status in the liver.

Development and validation of a hepatitis B virus DNA sequencing assay for assessment of antiviral resistance, viral genotype and surface antigen mutation status

The objective of this study was to develop a DNA sequencing assay that examines sensitively and reliably all conserved domains of the reverse transcriptase-encoding region of the HBV genome for antiviral resistance-associated mutations while simultaneously producing ample information for precise genotyping and determination of HBsAg mutation. This assay was used to examine 1000 de-identified HBV DNA positive samples with known viral loads from a broad-based, unselected patient population from across the United States. Of these, 946 were assayed successfully. Antiviral resistance-associated mutations were identified in 104 samples. The escape mutation sG145R in the surface antigen was identified in 0.8% of patient samples. Infections with genotypes A, B, C, D, E, F, G and H were observed in 36.6%, 19.6%, 21.7%, 13.5%, 3.6%, 0.7%, 2.2%, and 0.5% of patient samples respectively. Fifteen samples (1.6%) appeared to harbor infections with multiple genotypes as shown by the presence of double peaks throughout sequence electropherograms. The limit of detection of this assay was approximately 150IU/mL.

HBsAg blood screening and diagnosis: performance evaluation of the ARCHITECT HBsAg qualitative and ARCHITECT HBsAg qualitative confirmatory assays

A low initial reactive rate for screening assays is important for time- and cost-effective infectious disease testing. Therefore, the new ARCHITECT HBsAg Qualitative screening assay, in conjunction with the new ARCHITECT HBsAg Qualitative Confirmatory assay, was introduced. As the role of hepatitis B surface antigen (HBsAg) as surrogate marker for HBV resolution and the monitoring of drug effectiveness are becoming increasingly important, the established ARCHITECT HBsAg Quantitative assay remains available on the market. Precision, sensitivity, and specificity of the newly developed screening assay were in the range of established HBsAg assays. Seroconversion sensitivity was slightly superior compared to other commercially available assays. An initial reactive rate of 0.2% (without HBsAg-confirmed positive samples of 0.17%) for the ARCHITECT HBsAg Qualitative assay was observed. As the new screening assay is a 1-step assay format, the "high-dose hook effect" was investigated to assess the risk of false-negative results, but even very high positive HBsAg samples obtained signals clearly above the cutoff.

Clinical utility of hepatitis B surface antigen quantitation in patients with chronic hepatitis B: a review

This clinically relevant review focuses on recent findings concerning hepatitis B surface antigen (HBsAg) quantitation in untreated patients and treated patients with chronic hepatitis B. Recent studies and emerging data have shown that both HBsAg and hepatitis B virus (HBV) DNA levels decline during the natural course of a chronic HBV infection; they are lowest in the inactive phase, which is also characterized by the highest HBsAg/HBV DNA ratio. It has been demonstrated that the combined use of HBsAg and HBV DNA levels might help in the identification of true inactive carriers with high accuracy. Retrospective analyses of HBsAg levels in patients undergoing therapy have suggested a role for HBsAg quantitation in monitoring the response to therapy. In comparison with nucleos(t)ide analogues (NAs), interferon-based therapy results in greater overall declines in serum HBsAg levels. A rapid on-treatment decline in HBsAg levels appears to be predictive of a sustained response. With the aid of HBsAg quantitation, it appears that we can anticipate an individualized approach to tailoring the treatment duration. The proposal of early stopping rules for patients not responding to pegylated interferon (according to a lack of any HBsAg decline) represents a step toward a response-guided approach. The development of stopping rules for patients treated with NAs is desirable for reducing the need for lifelong therapy. However, before stopping rules for antiviral therapy can be applied, we need to learn more about the kinetics of HBsAg declines during the natural history of the infection and as a response to therapy so that we can better define the best timing, the relevant HBsAg cutoff levels, and the best ways to apply these rules in clinical practice.

Quantitative hepatitis B surface antigen and hepatitis B e antigen titers in prediction of treatment response to entecavir

Quantitative hepatitis B surface antigen (qHBsAg) and quantitative hepatitis B e antigen (qHBeAg) titers are emerging as useful tools for measuring viral loads and for predicting the virological response (VR) and serological response (SR) to pegylated interferon therapy. However, the clinical utility of these assays in patients taking entecavir (ETV) is largely unknown. Treatment-naive patients with chronic hepatitis B (CHB) who were taking ETV for 2 years were enrolled. The qHBsAg and qHBeAg levels were serially measured with the Architect assay. From 95 patients, 60.0% of whom were hepatitis B e antigen-positive [HBeAg(+)], 475 samples were analyzed. The median baseline log hepatitis B virus (HBV) DNA, log qHBsAg, and log qHBeAg values were 6.73 copies/mL (4.04-9.11 copies/mL), 3.58 IU/mL (1.17-5.10 IU/mL), and 1.71 Paul Ehrlich (PE) IU/mL (-0.64 to 2.63 PE IU/mL), respectively. For the prediction of VR (HBV DNA < 60 copies/mL at 24 months) in HBeAg(+) patients, baseline alanine aminotransferase (P = 0.013), HBV DNA (P = 0.040), and qHBsAg levels (P = 0.033) were significant. For the prediction of VR, the area under the curve for the baseline log qHBsAg level was 0.823 (P < 0.001); a cutoff level of 3.98 IU/mL (9550 IU/mL on a nonlogarithmic scale) yielded the highest predictive value with a sensitivity of 86.8% and a specificity of 78.9%. As for SR (HBeAg loss at 24 months), the reduction of qHBeAg was significantly greater in the SR(+) group versus the SR(-) group. The sensitivity and specificity were 75.0% and 89.8%, respectively, with a decline of 1.00 PE IU/mL at 6 months. With ETV therapy, the correlation between HBV DNA and qHBsAg peaked at 6 months in HBeAg(+) patients.

CONCLUSION

Both qHBsAg and qHBeAg decreased significantly with ETV therapy. The baseline qHBsAg levels and the on-treatment decline of qHBeAg in HBeAg(+) patients were proven to be highly useful in predicting VR and SR, respectively. The determination of qHBsAg and qHBeAg can help us to select the appropriate strategy for the management of patients with CHB. However, the dynamic interplay between qHBsAg, qHBeAg, and HBV DNA during antiviral therapy remains to be elucidated.

[HBsAg quantification: virological significance]

HBsAg is a classic marker of hepatitis B virus infection. Since the levels of serum HBsAg are correlated to those of intrahepatic cccDNA, HBsAg quantification indirectly reflects the number of infected hepatocytes. The kinetics of serum HBsAg decline seems to be a predictive marker for sustained virological response, and clearance of HBsAg. This new tool may be clinically relevant for the monitoring and optimization of hepatitis B treatments. To fulfill this objective, prospective studies are still warranted for the the spread of sensitive and standardized techniques standardization of the quantification assays and to define cut off values with clinical predictive values.

[HBsAg seroclearance: prognostic value for the response to treatment and the long-term outcome]

Chronic hepatitis B is a major cause of liver disease worldwide, ranking as the first cause of cirrhosis and hepatocellular carcinoma. Hepatitis B surface antigen (HBsAg) is usually used as a qualitative marker for the diagnosis of hepatitis B virus (HBV) infection. HBsAg clearance is the closest to cure outcome as one can expect to achieve in hepatitis B. Support for this comes from natural history studies demonstrating increased length of survival, lower rates of hepatic decompensation, reduction in the frequency of hepatocellular carcinoma, and regression of liver fibrosis in patients who clear HBsAg. HBsAg seroclearance may occur spontaneously at a yearly incidence of 1-2%, preceded usually by a long period of inactive disease. Interferon treatment enhanced HBsAg seroclearance by approximately three-fold in western studies and sixfold in Asian studies compared with non-treated patients. Pegylated interferon induced a 10-15% yearly rate of HBsAg seroclearance in patients who developed sustained virological response in clinical trials. By contrast, treatment with nucleos (t) ides analogues did not significantly affect the rate of HBsAg seroclearance, especially in patients with hepatitis B e antigen (HBeAg) - negative disease. Recently, serum HBsAg has been shown to be a surrogate marker of covalently closed circular DNA (cccDNA) concentration in the liver. Quantification of serum HBsAg has also been recently shown to be a promising tool for monitoring virologic response in HBeAg-negative patients treated with pegylated interferon.

Review article: chronic hepatitis B - anti-viral or immunomodulatory therapy?

BACKGROUND

First-line treatment options for chronic hepatitis B (CHB) consist of nucleos(t)ide analogues with a high barrier to resistance (entecavir and tenofovir) or the immunomodulatory agent peginterferon (PEG-IFN). The optimal choice for individual patients remains controversial.

AIM

To review treatment options for CHB, with a focus on deciding between prolonged nucleos(t)ide analogue therapy or a finite course of PEG-IFN.

METHODS

A comprehensive literature search was undertaken.

RESULTS

Long-lasting, treatment-maintained suppression of hepatitis B virus (HBV) DNA without resistance is achievable in most patients by entecavir or tenofovir. A sustained off-treatment response is, however, unlikely and long-term therapy must be anticipated. PEG-IFN offers a higher rate of sustained response in a subgroup of patients, but is frequently complicated by side effects. Pre-treatment predictors of response, including HBV genotype, alanine aminotransferase and HBV DNA levels, aid in selecting patients for PEG-IFN therapy. Furthermore, on-treatment markers such as quantitative hepatitis B surface antigen may be applied to identify nonresponders early during the PEG-IFN treatment course, thereby preventing unnecessary treatment.

CONCLUSIONS

Both nucleos(t)ide analogues and PEG-IFN can be prescribed as first-line treatment options for CHB. However, PEG-IFN should only be considered for patients with a high chance of response based on pre-treatment and on-treatment factors.

Kinetics of hepatitis B surface antigen differ between treatment with peginterferon and entecavir

BACKGROUND & AIMS

We aimed to investigate serum hepatitis B surface antigen (HBsAg) levels in patients with chronic hepatitis B virus (HBV) infection during peginterferon (PEG-IFN) and entecavir (ETV) monotherapy.

METHODS

HBsAg was quantified (Abbott ARCHITECT) at baseline and during antiviral therapy (weeks 12, 24, 36, 48) in hepatitis B e antigen (HBeAg-) positive patients treated with ETV (n=33) or PEG-IFN (n=61) and in HBeAg-negative patients treated with ETV (n=37) or PEG-IFN (n=69).

RESULTS

Within the HBeAg-positive population, patients treated with PEG-IFN tended to have a steeper HBsAg decline than ETV-treated patients (mean decline 0.94 versus 0.38 log IU/ml at week 48, p=0.07 for comparison of the slope of HBsAg decline). The HBsAg decline was larger in those patients who became HBeAg negative, irrespective of the treatment regimen. A decline in HBsAg was confined to ETV-treated patients with elevated baseline alanine aminotransferase (ALT) levels, whereas HBsAg decline was not associated with baseline ALT in patients treated with PEG-IFN. Within the HBeAg-negative population, PEG-IFN induced a significant HBsAg decline, while HBsAg did not decrease in ETV-treated patients (0.56 versus -0.10 log IU/ml, p<0.001). Both in HBeAg-positive and HBeAg-negative patients, the decline in serum HBV DNA was larger in patients who received ETV as compared to patients treated with PEG-IFN.

CONCLUSIONS

In HBeAg-positive patients, the decline in serum HBsAg is mainly confined to patients who clear HBeAg, by either PEG-IFN or ETV treatment. In HBeAg-negative patients, PEG-IFN therapy resulted in a significant reduction in HBsAg levels, whereas HBsAg did not decrease in ETV-treated patients.

Clevudine-induced viral response, associated with continued reduction of HBsAg titer, was durable after the withdrawal of therapy

BACKGROUND

This study was conducted to evaluate the durability of clevudine-induced viral response after the withdrawal of treatment.

METHODS

Patients who showed a complete response [alanine aminotransferase (ALT) normalization and hepatitis B virus (HBV) DNA <4,700 copies/mL for hepatitis B envelope antigen (HBeAg)-negative patients; ALT normalization, HBV DNA <4,700 copies/mL, and HBeAg seroconversion for HBeAg-positive patients] in the previous clevudine phase III trials were followed for an additional 96 weeks without any treatment for hepatitis B.

RESULTS

Of the 63 patients in the study cohort, 73% and 35% of the patients had HBV DNA <141,500 and <4,700 copies/mL, respectively, and 75% of the patients had normal ALT at the end of follow-up. HBeAg seroconversion was maintained in 81% of the patients and hepatitis B surface antigen (HBsAg) loss occurred in 3 patients. Continued HBsAg titer decrease (-0.5 log IU/mL) was observed in the sustained viral responders, suggesting the reduction of covalently closed circular DNA in hepatocytes.

CONCLUSIONS

The clevudine-induced viral response was durable in the majority of patients for 2 years after the withdrawal of treatment.

Quantification of HBsAg: Basic virology for clinical practice

Hepatitis B surface antigen (HBsAg) is produced and secreted through a complex mechanism that is still not fully understood. In clinical fields, HBsAg has long served as a qualitative diagnostic marker for hepatitis B virus infection. Notably, advances have been made in the development of quantitative HBsAg assays, which have allowed viral replication monitoring, and there is an opportunity to make maximal use of quantitative HBsAg to elucidate its role in clinical fields. Yet, it needs to be underscored that a further understanding of HBsAg, not only from clinical point of view but also from a virologic point of view, would enable us to deepen our insights, so that we could more widely expand and apply its utility. It is also important to be familiar with HBsAg variants and their clinical consequences in terms of immune escape mutants, issues resulting from overlap with corresponding mutation in the P gene, and detection problems for the HBsAg variants. In this article, we review current concepts and issues on the quantification of HBsAg titers with respect to their biologic nature, method principles, and clinically relevant topics.

Chronic hepatitis B: peginterferon or nucleos(t)ide analogues?

Pegylated interferon-α (PEG-IFN) is still an important treatment option for both HBeAg-positive and HBeAg-negative chronic hepatitis B (CHB) patients even with the availability of potent nucleos(t)ide analogues (NUCs) with a low risk of resistance. The major advantages of PEG-IFN-based treatment include the limited duration of treatment and the good probability of achieving a sustained off-treatment response. Responders to PEG-IFN have an increased probability of HBsAg loss and survival. However, the limited number of patients who achieve a response and the high costs and side-effects associated with PEG-IFN limit its clinical use. The potent NUCs entecavir and tenofovir are therefore often used as a first-line treatment option. Unfortunately, the off-treatment durability of response to NUCs is generally low, requiring long-term continuous therapy. Recent progress making it possible to select patients with a high probability of achieving a response to PEG-IFN, and to adapt therapy early on in probable non-responders, should help further optimize the utilization of PEG-IFN in CHB.

HBsAg seroclearance in chronic hepatitis B: implications for hepatocellular carcinoma

GOALS AND BACKGROUND

The long-term clinical course, including the development of hepatocellular carcinoma (HCC) after hepatic B surface antigen (HBsAg) seroclearance is not established. We discovered that the incidence of HCC and the risk factors for HCC in chronic hepatitis B (CHB) patients after HBsAg seroclearance.

STUDY

During 28 years, 96 CHB patients with HBsAg seroclearance were retrospectively reviewed. These patients continued to undergo HCC surveillance. The median follow-up time from initial visit was 166.5 months (range, 7 to 321 mo).

RESULTS

The mean age at the initial visit and at the time of seroclearance was 39.2 ± 10.6 years and 46.4 ± 9.9 years, respectively. The mean age at the time of HBsAg seroclearance was significantly lower (P=0.03) in patients with spontaneous HBsAg seroclearance than patients with treatment-associated HBsAg seroclearance. During a median of 56 months (range, 7 to 238 mo) of follow-up after HBsAg seroclearance, 6 (6.5%) patients developed HCC. The mean age at the time of developing HCC was 55.8 ± 10.3 years. On univariate analysis, the evidence of liver cirrhosis from the time of HBsAg seroclearance and age more than 45 years at the time of HBsAg seroclearance were significant risk factors for HCC development. In multivariate analysis, the evidence of liver cirrhosis at HBsAg seroclearance was the only significant risk factor for HCC development.

CONCLUSIONS

HCC can develop after HBsAg seroclearance in patients with known cirrhosis. Patients who achieved HBsAg seroclearance at older age (>45) may have undiagnosed cirrhosis and hence remain at risk for HCC. HCC surveillance should be carried out for both of those patient populations.

Serum HBsAg quantification to predict response to peginterferon therapy of e antigen positive chronic hepatitis B

BACKGROUND

On-treatment predictors of response to peginterferon can guide individualization of therapy in chronic hepatitis B virus infection.

AIM

To investigate the use of serum hepatitis B surface antigen quantification to predict sustained response.

METHODS

Hepatitis B e antigen-positive chronic hepatitis B patients who received peginterferon for 32-48 weeks with or without lamivudine combination were studied. Sustained response was defined as hepatitis B e antigen seroconversion and chronic hepatitis B virus DNA <10 000 copies/mL until 12 months post-treatment.

RESULTS

Twenty-one of 92 (23%) patients achieved sustained response. At month 6, the area under receiver operating characteristics curve for hepatitis B surface antigen to predict sustained response was 0.77 (95% confidence interval 0.65-0.89, P < 0.001). An hepatitis B surface antigen cutoff at 300 IU/mL at month 6 could give the maximum combination of sensitivity (62%) and specificity (89%) to predict sustained response. Nine of 21 (43%) sustained responders vs. 9 of 71 (13%) nonsustained responders had >1 log hepatitis B surface antigen reduction at month 6 (P < 0.001). Combined hepatitis B surface antigen ≤ 300 IU/mL and >1 log reduction at month 6 had sensitivity, specificity, positive and negative predictive values of 43%, 96%, 75% and 85% to predict sustained response, respectively.

CONCLUSION

On-treatment serum hepatitis B surface antigen can predict response to peginterferon therapy in chronic hepatitis B.

Relationship between serum hepatitis B virus DNA and surface antigen with covalently closed circular DNA in HBeAg-negative patients

Hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) is responsible for viral persistence. This study aimed to investigate the serum surrogate markers for cccDNA and to evaluate the intrahepatic viral events associated with disease activity in HBeAg-negative chronic hepatitis B patients. Thirty-three treatment-naïve patients with a negative HBeAg who had a liver biopsy were studied. Active disease was defined as a serum alanine aminotransferase >40 IU/L and a serum HBV DNA >10,000 copies/ml. This study showed significant correlation between serum HBV DNA and both log cccDNA (r = 0.41, P = 0.018) and log total intrahepatic HBV DNA (r = 0.71, P < 0.0001). No significant correlation was observed between serum HBsAg and log cccDNA (P = 0.15) or log total intrahepatic HBV DNA (P = 0.97). Fourteen and 19 patients had inactive and active disease, respectively. The median log cccDNA and log total intrahepatic HBV DNA (copies/10(6) cells) were significantly higher in patients with active disease compared with those with inactive disease (4.11 vs. 3.53, P = 0.03 and 5.46 vs. 4.64, P < 0.001, respectively). The HBV replicative efficiency, defined as the ratio of serum HBV DNA to cccDNA, was approximately 20% higher in patients with active disease. No significant difference was observed in the HBsAg levels and the ratio of serum HBsAg to cccDNA between the two groups. In conclusion, serum HBV DNA, but not HBsAg, reflects the amount of cccDNA and the replication efficiency of HBV in patients with HBeAg-negative chronic hepatitis B.