Switching to peginterferon for chronic hepatitis B patients with hepatitis B e antigen seroconversion on entecavir – A prospective study

Nucleos(t)ide analogues (NA) are effective in suppressing hepatitis B virus (HBV) replication, but most patients require long‐term treatment. This study aimed to investigate switching to peginterferon as a strategy to stop NA. Hepatitis B e antigen (HBeAg)‐positive chronic hepatitis B patients who developed HBeAg seroconversion during NA treatment were studied. All patients received open‐label peginterferon alfa‐2a 180 μg/wk for 48 weeks, and NA was stopped at week 4 of peginterferon treatment. The primary endpoint was sustained response, which was defined as negative HBeAg, positive anti‐HBe and HBV DNA <2000 IU/mL at week 72. Other secondary endpoints including HBsAg loss at week 72 were also studied. Forty‐one patients treated with entecavir for 56 ± 23 months were recruited. Sustained response was achieved in 30 patients (73%, 95% confidence interval 58%‐84%). At week 72, 31 (76%) patients had HBeAg seroconversion, 56 (23%) patients had undetectable HBV DNA, 31 (76%) patients had normal ALT, and 6 patients (15%) had HBsAg loss. Baseline HBsAg level was the best predictor for both sustained response and HBsAg loss; the best HBsAg cut‐off for sustained response was <1500 IU/mL and that for HBsAg loss was <500 IU/mL by receiver operating characteristic curve analysis. Twenty‐two of 25 (88%) patients with baseline HBsAg <1500 IU/mL had sustained response. Five of 10 (50%) patients with baseline HBsAg <500 IU/mL developed HBsAg loss. Switching to peginterferon can be considered as a treatment option in NA‐treated patients with HBeAg seroconversion, particularly among those with lower HBsAg levels.     

Baseline HBsAg predicts response to pegylated interferon-α2b in HBeAg-positive chronic hepatitis B patients

AIM: To evaluate the predictive effect of baseline hepatitis B surface antigen (HBsAg) on response to pegylated interferon (PEG-IFN)-α2b in hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) patients.METHODS: This retrospective analysis compared the treatment efficacy of PEG-IFN-α2b alone in 55 HBeAg-positive CHB patients with different baseline HBsAg levels. Serum HBV DNA load was measured at baseline, and at 12, 24 and 48 wk of therapy. Virological response was defined as HBV DNA < 1000 IU/mL. Serum HBsAg titers were quantitatively assayed at baseline, and at 12 and 24 wk.RESULTS: Eighteen patients had baseline HBsAg > 20 000 IU/mL, 26 patients had 1500-20000 IU/mL, and 11 patients had < 1500 IU/mL. Three (16.7%), 11 (42.3%) and seven (63.6%) patients in each group achieved a virological response at week 48, with a significant difference between groups with baseline HBsAg levels > 20000 or < 20000 IU/mL (P = 0.02). Thirteen patients had an HBsAg decline > 0.5 log₁₀ and 30 patients < 0.5 log₁₀ at week 12; and 6 (46.2%) and 10 (33.3%) in each group achieved virological response at week 48, with no significant difference between the two groups (P = 0.502). Eighteen patients had an HBsAg decline > 1.0 log₁₀ and 30 patients < 1.0 log₁₀ at week 24, and 8 (44.4%) and 11 (36.7%) achieved a virological response at week 48, with no significant difference between the two groups (P = 0.762). None of the 16 patients with HBsAg > 20000 IU/mL at week 24 achieved a virological response at week 48.CONCLUSION: Baseline HBsAg level in combination with HBV DNA may become an effective predictor for guiding optimal therapy with PEG-IFN-α2b against HBeAg-positive CHB.     

Comparison between quantitative hepatitis B surface antigen,hepatitis B e‐antigen and hepatitis B virus DNA levels for predicting virological response to pegylated interferon‐α‐2b therapy in hepatitis B e‐antigen‐positive chronic hepatitis B

Aim: The aim of this study was to compare the clinical applicability of quantitative serum hepatitis B surface antigen (HBsAg), hepatitis B e‐antigen (HBeAg) and hepatitis B virus (HBV) DNA for predicting virological response (VR) to pegylated interferon (PEG‐IFN) therapy. Methods: Thirty HBeAg‐positive chronic hepatitis B patients who received PEG‐IFN‐α‐2b for 48 weeks were enrolled. Quantitative HBsAg, HBeAg and HBV DNA were measured before, during and after the therapy. Paired liver biopsies were performed before and after treatment for covalently closed circular (ccc)DNA and intrahepatic HBV DNA analysis. Results: VR at 48 weeks post‐treatment, defined as HBeAg seroconversion and HBV DNA less than 10 000 copies/mL was achieved in 10 (33.3%) patients. Responders had significantly lower baseline HBsAg, HBeAg, cccDNA and intrahepatic HBV DNA levels than non‐responders. Baseline and reduced levels of log₁₀ HBsAg and log₁₀ HBeAg correlated well with those of log₁₀ cccDNA and log₁₀ total intrahepatic HBV DNA. Responders showed consistent decrease in serum HBsAg, HBeAg and HBV DNA levels during therapy. HBeAg level of 2.0 log₁₀ sample to cut‐off ratio at week 24 on therapy provided the best prediction of sustained virological response, with sensitivity and negative predictive values of 85% and 92%, respectively. One patient (3.3%) who cleared HBsAg at follow up exhibited a more rapid decline in serum HBsAg during therapy than those who developed VR without HBsAg clearance. Conclusion: Quantitative measurement of serum HBeAg during therapy may be superior to serum HBsAg and HBV DNA as a prediction of HBeAg seroconversion. Kinetics of HBsAg levels on therapy may help predict HBsAg clearance after treatment.     

Analysis of hepatitis B surface antigen (HBsAg) using high‐sensitivity HBsAg assays in hepatitis B virus carriers in whom HBsAg seroclearance was confirmed by conventional assays

Aim

We investigated the utility of high‐sensitivity hepatitis B surface antigen (HBsAg) assays compared with conventional HBsAg assays.

Methods

Using serum samples from 114 hepatitis B virus (HBV) carriers in whom HBsAg seroclearance was confirmed by conventional HBsAg assays (cut‐off value, 0.05 IU/mL), the amount of HBsAg was re‐examined by high‐sensitivity HBsAg assays (cut‐off value, 0.005 IU/mL). Cases negative for HBsAg in both assays were defined as consistent cases, and cases positive for HBsAg in the high‐sensitivity HBsAg assay only were defined as discrepant cases.

Results

There were 55 (48.2%) discrepant cases, and the range of HBsAg titers determined by high‐sensitivity HBsAg assays was 0.005–0.056 IU/mL. Multivariate analysis showed that the presence of nucleos(t)ide analog therapy, liver cirrhosis, and negative anti‐HBs contributed to the discrepancies between the two assays. Cumulative anti‐HBs positivity rates among discrepant cases were 12.7%, 17.2%, 38.8%, and 43.9% at baseline, 1 year, 3 years, and 5 years, respectively, whereas the corresponding rates among consistent cases were 50.8%, 56.0%, 61.7%, and 68.0%, respectively. Hepatitis B virus DNA negativity rates were 56.4% and 81.4% at baseline, 51.3% and 83.3% at 1 year, and 36.8% and 95.7% at 3 years, among discrepant and consistent cases, respectively. Hepatitis B surface antigen reversion was observed only in discrepant cases.

Conclusions

Re‐examination by high‐sensitivity HBsAg assays revealed that HBsAg was positive in approximately 50% of cases. Cumulative anti‐HBs seroconversion rates and HBV‐DNA seroclearance rates were lower in these cases, suggesting a population at risk for HBsAg reversion.     

Long‐term entecavir therapy results in falls in serum hepatitis B surface antigen levels and seroclearance in nucleos(t)ide‐naïve chronic hepatitis B patients

Entecavir (ETV) is reported to result in suppression of hepatitis B virus DNA (HBV DNA) replication with minimal drug resistance. However, information on the long‐term effect of such therapy on serum hepatitis B surface antigen (HBsAg) level and elimination of HBsAg is not available. ETV therapy was started in 553 nucleos(t)ide‐naïve patients with chronic hepatitis B infection (HBeAg positive: 45%) in our hospital. Serum HBsAg levels were measured serially by the Architect assay. The median baseline HBsAg was 2180 IU/mL (0.12–243 000 IU/mL), and median follow‐up period was 3.0 years, with 529, 475, 355, 247 and 163 patients followed‐up for 1, 2, 3, 4 and 5 years, respectively. At year 5, the mean log HBsAg decline from baseline was −0.48 log IU/mL, and the cumulative HBsAg clearance rate was 3.5%. Multivariate analysis identified HBV DNA level at baseline (<3.0 log copies IU/mL, odd ratio = 10.2; 95% confidence interval = 1.87–55.5, P = 0.007) and HBsAg level (<500 IU/mL, odd ratio = 29.4; 95% confidence interval = 2.80–333, P = 0.005) as independent predictors of HBsAg seroclearance. These results indicate that although serum HBsAg level declines gradually during ETV therapy, HBsAg seroclearance remains a rare event.     

Hepatitis B surface antigen levels during natural history of chronic hepatitis B: A Chinese perspective study

AIM: To determine the baseline hepatitis B surface antigen (HBsAg) levels during the different phases of chronic hepatitis B (CHB) patients in China.METHODS: Six hundred and twenty-three hepatitis B virus or un-infected patients not receiving antiviral therapy were analyzed in a cross-sectional study. The CHB patients were classified into five phases: immune-tolerant (IT, n = 108), immune-clearance (IC, n = 161), hepatitis B e antigen negative hepatitis (ENH, n = 149), low-replicative (LR, n = 135), and liver cirrhosis (LC, n = 70). HBsAg was quantified (Abbott ARCHITECT assay) and correlated with hepatitis B virus (HBV) DNA, and serum alanine aminotransferase/aspartate aminotransferase (ALT/AST) in each phase of CHB was also determined.RESULTS: Median HBsAg titers were different in each phase of CHB (P < 0.001): IT (4.85 log₁₀ IU/mL), IC (4.36 log₁₀ IU/mL), ENH (2.95 log₁₀ IU/mL), LR (3.18 log₁₀ IU/mL) and LC (2.69 log₁₀ IU/mL). HBsAg titers were highest in the IT phase and lowest in the LC phase. Serum HBsAg titers showed a strong correlation with HBV viral load in the IC phase (r = 0.683, P < 0.001). No correlation between serum HBsAg level and ALT/AST was observed.CONCLUSION: The mean baseline HBsAg levels differ significantly during the five phases of CHB, providing evidence on the natural history of HBV infection. HBsAg quantification may predict the effects of immune-modulator or oral nucleos(t)ide analogue therapy.     

Serial HBV DNA levels in patients with persistently normal transaminase over 10 years following spontaneous HBeAg seroconversion

Earlier studies addressing the hepatitis B virus (HBV) DNA cut-off level for inactive chronic HBV infection largely involved patients with normal alanine aminotransferase (ALT) for only 1-2 years and based on a single time HBV DNA assay. This study was conducted to address this issue using serial HBV DNA assays in patients with persistently normal ALT (PNALT) over 10 years following spontaneous hepatitis B e antigen (HBeAg) seroconversion. Serial serum specimens (mean 9 samples per patient) of 62 patients with PNALT and no disease progression over 10 years (median 18.1 years) after spontaneous HBeAg seroconversion were assayed for HBV DNA. Excluding assays within 1 year after HBeAg seroconversion, 21% and 82.3% of the patients with PNALT had HBV DNA levels persistently lower than 4 log(10) and 5 log(10) copies/mL, respectively, and only 8% had a level ≥ 5 log(10) copies/mL in at least two assays. Of the 27 patients with PNALT defined by ALT <30 U/L for male and <19 U/L for female, only 33% had serum HBV DNA level persistently <4 log(10) copies/mL. There was no significant difference in the serial HBV DNA changes among patients with different gender, HBV genotype or age at HBeAg seroconversion. Liver biopsy in nine patients invariably showed minimal necroinflammation and one showed Ishak fibrosis score 4. These results suggest that 5 log(10) copies/mL (20,000 IU/mL) is a more appropriate cut-off HBV DNA level for inactive chronic HBV infection in the setting of PNALT.     

The HBV DNA cutoff value for discriminating patients with HBeAgnegative chronic hepatitis B from inactive carriers

Background

Patients with HBeAg-negative chronic hepatitis B (CHB) has a significantly different prognosis than inactive carriers; there is however, no reliable strategy for accurately differentiating these two disease conditions.

Objectives

To determine a strategy for discriminating patients with HBeAg-negative CHB from inactive carriers.

Materials and Methods

Consecutive inactive carriers (i.e. HBeAg-negativity, anti-HBe-positivity, normal ALT levels, and HBV DNA < 2000 IU/mL) were enrolled. HBV reactivation was defined as the elevation of the HBV DNA level to ≥ 2000 IU/mL. Patients were classified into true inactive carriers when their HBV DNA levels remained at < 2000 IU/mL or false inactive carriers when their HBV DNA levels increased to ≥ 2000 IU/mL during the first year.

Results

The Mean ± SD age of 208 inactive carriers (140 males) was 47.7 ± 12.6 years. The Mean ± SD serum ALT and HBV DNA levels were 22.8 ± 8.6 IU/L and 360 ± 482 IU/mL, respectively. HBV reactivation developed in 41 (19.7%) patients during the first year. Baseline HBV DNA and ALT levels differed significantly between true inactive and false inactive carriers. The AUROCs of the baseline ALT and HBV DNA levels for predicting a false inactive carrier were 0.609 and 0.831, respectively. HBV reactivation developed more often in patients with a baseline HBV DNA level of ≥ 200 IU/mL than in those with a baseline HBV DNA level of < 200 IU/mL during a Mean ± SD follow-up of 622 ± 199 days.

Conclusions

The HBV DNA level was useful for discriminating patients with HBeAg-negative CHB from true inactive carriers. The follow-up strategies applied to inactive carriers need to vary with their HBV DNA levels.     

Telbivudine vs tenofovir in hepatitis B e antigen-negative chronic hepatitis B patients: OPTIMA roadmap study

AIM To make efficacy and safety comparison of telbivudineraodmap and tenofovir-roadmap in hepatitis B e antigen(HBe Ag)-negative chronic hepatitis B(CHB) patients.METHODS This was the first prospective, randomised, two-arm, open-label, non-inferiority study in HBe Ag-negative CHB patients that compared telbivudine and tenofovir administered as per roadmap concept. Patients were treated up to 24 wk and, depending on virologic response, continued the same therapy or received addon therapy up to 104 wk. Eligible patients received an additional 52 wk of treatment in the extension period(i.e., up to 156 wk). Patients who developed virologic breakthrough(VB) while on monotherapy also received add-on therapy. The primary efficacy endpoint was the rate of patients achieving hepatitis B virus(HBV) DNA 300 copies/m L at week 52. Secondary efficacy endpoints included the rates of HBV DNA 300 and 169 copies/m L, HBV DNA change from baseline, alanine aminotransferase normalisation, hepatitis B surface antigen(HBs Ag) loss, HBs Ag seroconversion, VB, and emergence of resistance at various timepoints throughout the study. Safety and estimated glomerular filtration rate(e GFR) were also analysed.RESULTS A total of 241 patients were randomised. Non-inferiority of telbivudine arm to tenofovir arm was demonstrated at week 52(± 7 d window), with over 91% of patients in each treatment arm achieving HBV DNA level 300 copies/m L. Both arms were similar in terms of key secondary efficacy variables at weeks 104 and 156. The percentage of patients achieving HBV DNA 300 copies/m L remained high and was similar in the telbivudine and tenofovir arms at both weeks 104 and 156. Over 82% of patients in both arms achieved alanine aminotransferase normalisation at week 52, and this percentage remained high at weeks 104 and 156. Telbivudine treatment progressively reduced serum HBs Ag levels from baseline while no change was reported in quantitative HBs Ag during therapy with tenofovir. Both treaments showed acceptable safety profiles. The telbivudine arm showed e GFR improvement unlike the tenofovir arm.CONCLUSION Efficacy was shown for both telbivudine-roadmap and tenofovir-roadmap regimens in HBe Ag-negative CHB patients over 156 wk. Telbivudine arm was associated with renal improvement.     

Association of on‐treatment serum hepatitis B surface antigen level with sustained virological response to nucleos(t)ide analog in patients with hepatitis B e‐antigen positive chronic hepatitis B

Aim: This study evaluated the on‐treatment serum hepatitis B surface antigen (HBsAg) level during nucleos(t)ide analog (NUC) therapy and the correlation with off‐treatment sustained virological response (SVR). Methods: Fifty‐one consecutive patients with hepatitis B e‐antigen (HBeAg) positive chronic hepatitis B who achieved HBeAg loss/seroconversion after NUC therapy and completed 12 months or more of additional therapy were included. Serum HBsAg and hepatitis B virus (HBV) DNA levels were determined at baseline, 3, 6, 9 and 12 months, and at the end of treatment. SVR was defined as HBV DNA levels of less than 10 000 copies/mL until 6 or 12 months off‐treatment without reappearance of HBeAg. Results: Twenty‐two (43.1%) and 13 (25.5%) patients maintained SVR at 6 and 12 months off‐treatment, respectively. In univariate analyses, a decline of HBsAg of 0.5 log₁₀ IU/mL or less at 6 months (P = 0.006) and 12 months (P = 0.013), the mean change in HBsAg level at 6 months (P = 0.024), and lamivudine or entecavir treatment (P = 0.019) were significant predictive factors for SVR at 6 months off‐treatment. A decline of HBsAg of 0.5 log₁₀ IU/mL or less at 6 months and lamivudine or entecavir treatment were independent factors on multivariate analyses (odds ratio [OR], 16.67; 95% confidence interval [CI], 1.86–142.86 [P = 0.012]; and OR, 14.83; 95% CI, 1.18–185.73 [P = 0.036]; respectively). Conclusion: On‐treatment serum HBsAg level predicted early off‐treatment SVR to NUC therapy in patients infected with genotype C.     

Hepatitis B surface antigen loss and sustained viral suppression in Asian chronic hepatitis B patients: A community‐based real‐world study

Community‐based real‐world outcomes on effectiveness of antiviral therapies for chronic hepatitis B virus (CHB) in Asians are limited. Whether hepatitis B surface antigen (HBsAg) loss correlates with undetectable virus and alanine aminotransferase (ALT) normalization on treatment or what predicts risk of seroreversion or detectable virus after stopping therapy is unclear. We aim to evaluate rates and predictors of HBsAg loss, seroconversion, ALT normalization and undetectable HBV DNA, including HBsAg seroreversion or re‐emergence of HBV DNA among Asian CHB patients. We retrospectively evaluated 1072 CHB adults on antiviral therapy at two community gastroenterology clinics from 1997 to 2015. Rates of HBsAg loss, ALT normalization, achieving undetectable HBV DNA and developing surface antibody (anti‐HBs) were stratified by HBeAg status. Following HBsAg loss, HBsAg seroreversion or re‐emergence of detectable HBV DNA was analysed. With median treatment of 76.7 months, the overall rate of HBsAg loss was 4.58%, with similar HBsAg loss rates between HBeAg‐positive and HBeAg‐negative patients (4.44% vs 4.71%, P=.85) in a predominantly Asian population (98.1%). Among HBsAg loss patients, 33.3% developed anti‐HBs, 95.8% achieved undetectable virus and 66.0% normalized ALT. No significant baseline or on‐treatment predictors of HBsAg loss were observed. While six patients who achieved HBsAg loss had seroreversion with re‐emergence of HBsAg positivity, viral load remained undetectable, demonstrating the sustainability of viral suppression. Among a large community‐based real‐world cohort of Asian CHB patients treated with antiviral therapy, rate of HBsAg loss was 4.58%. Despite only 33.3% of HBsAg loss patients achieving anti‐HBs, nearly all patients achieved sustained undetectable virus.     

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.     

Sequential therapy with adefovir dipivoxil and pegylated Interferon Alfa‐2a for HBeAg‐negative patients

Summary. To assess the impact of sequential therapy with adefovir dipivoxil (ADV) and pegylated interferon alfa‐2a (PEG‐IFN) on virological (serum HBV‐DNA) and serological (serum HBsAg) response in 20 consecutive HBeAg‐negative patients. Patients received ADV for 20 weeks, then ADV and PEG‐IFN for 4 weeks and lastly PEG‐IFN for 44 weeks. Serum HBV‐DNA and HBsAg were assessed at baseline, during therapy (weeks 20, 44 and 68) and follow‐up (weeks 92 and 116). Sustained virological response (SVR) was defined as serum HBV‐DNA <10 000 copies/mL (partial) or <70 copies/mL (complete) 24 weeks after stopping treatment. A serological response was defined as a serum HBsAg decrease ≥1 log₁₀IU/mL at the end of treatment. Baseline median serum HBV‐DNA and HBsAg levels were 7.6 log₁₀copies/mL and 3.8 log₁₀IU/mL, respectively. Ten patients (50%) achieved SVR, six of them had partial response and four complete response. Four patients (20%) achieved serological response. Complete SVRs showed a major and steep decline in HBsAg level with a median decrease of 0.5, 1.6 and 2.0 log₁₀IU/mL at treatment week 20, 44 and 68, respectively. Partial SVRs showed a slight and slow decline in serum HBsAg level (0.1, 0.4, and 0.6 log IU/mL at weeks 20, 44 and 68, respectively). On‐treatment serum HBsAg decrease had a high accuracy to predict SVR (AUROC = 0.88). Our results suggest that sequential therapy might be an interesting strategy for HBeAg‐negative patients. Serum HBsAg kinetics seem to be an accurate tool to predict SVR. Large clinical trials are needed to explore this strategy with more potent analogues.     

Molecular and Serological Characterization of Hepatitis B Virus (HBV)-Positive Samples with Very Low or Undetectable Levels of HBV Surface Antigen

Background: Gaps remain in the detection of nucleic acid test (NAT) yield and occult hepatitis B virus (HBV) infection (OBI) by current HBV surface antigen (HBsAg) assays. The lack of detection may be due to HBsAg levels below current assay detection limits, mutations affecting HBsAg assays or HBsAg levels, or the masking of HBsAg by antibody to HBsAg (anti-HBs). In this study, we evaluate the incremental detection of NAT yield and OBI from five diverse geographic areas by an improved sensitivity HBsAg assay and characterize the samples relative to the viral load, anti-HBs status, and PreS1–S2–S mutations. Included is a comparison population with HBV DNA levels comparable to OBI, but with readily detectable HBsAg (High Surface–Low DNA, HSLD). Methods: A total of 347 samples collected from the USA, South Africa, Spain, Cameroon, Vietnam, and Cote D’Ivoire representing NAT yield (HBsAg(−), antibody to HBV core antigen (anti-HBc)(−), HBV DNA(+), N = 131), OBI (HBsAg(−), anti-HBc(+), HBV DNA(+), N = 188), and HSLD (HBsAg(+), anti-HBc(+), HBV DNA(+), N = 28) were tested with ARCHITECT HBsAg NEXT (HBsAgNx) (sensitivity 0.005 IU/mL). The sequencing of the PreS1–S2–S genes from a subset of 177 samples was performed to determine the genotype and assess amino acid variability, particularly in anti-HBs(+) samples. Results: HBsAgNx detected 44/131 (33.6%) NAT yield and 42/188 (22.3%) OBI samples. Mean HBV DNA levels for NAT yield and OBI samples were lower in HBsAgNx(−) (50.3 and 25.9 IU/mL) than in HBsAgNx(+) samples (384.1 and 139.5 IU/mL). Anti-HBs ≥ 10 mIU/mL was present in 28.6% HBsAgNx(+) and 45.2% HBsAgNx(−) OBI, and in 3.6% HSLD samples. The genotypes were A1, A2, B, C, D, E, F, and H. There was no significant difference between HBsAgNx(−) and HBsAgNx(+) in the proportion of samples harboring substitutions or in the mean number of substitutions per sample in PreS1, PreS2, or S for the NAT yield or OBI (p range: 0.1231 to >0.9999). A total of 21/27 (77.8%) of HBsAgNx(+) OBI carried S escape mutations, insertions, or stop codons. HSLD had more PreS1 and fewer S substitutions compared to both HBsAgNx(−) and HBsAgNx(+) OBI. Mutations/deletions associated with impaired HBsAg secretion were observed in the OBI group. Conclusions: HBsAgNx provides the improved detection of NAT yield and OBI samples. Samples that remain undetected by HBsAgNx have exceptionally low HBsAg levels below the assay detection limit, likely due to low viremia or the suppression of HBsAg expression by host and viral factors.     

Clinical Implications of HBsAg Quantification in Patients with Chronic Hepatitis B

Quantification of serum hepatitis B surface antigen (HBsAg) helps the management of patients with chronic hepatitis B virus (HBV) infection. Median HBsAg levels differ significantly during the natural history of HBV infection, progressively declining from immune tolerance to inactive phase. The combination of an HBsAg <1000 IU/mL and HBV DNA <2000 IU/mL at a single time point accurately identifies true inactive carriers. During antiviral treatment, HBsAg levels decline more rapidly in patients under peg-interferon (Peg-IFN) than in those under nucleos(t)ide analogues (NUC), and in responders to peg-IFN compared to non responders suggesting that a response-guided therapy in both HBeAg-positive and -negative patients treated with Peg-IFN could improve to cost-effectiveness of this therapeutic approach. Given the low rates of HBsAg clearance on NUC therapy, new studies to test whether Peg-IFN and NUC combination fosters HBsAg decline in long-term responders to NUC, are being explored.     

Peg-IFNα-2a Contributed to HBs Antigen Seroclearance in a Patient with Chronic Hepatitis B Administered Nucleic Acid Analogs: A Three-year Follow-up

We treated a 51-year-old Japanese man with chronic hepatitis B (viral load 7.6 LC/mL, genotype C). Hepatitis B virus DNA and HBe antigen were undetectable during the administration of the nucleic acid analogs (NUCs) lamivudine and adefovir, although the concentration of HBs antigen (HBsAg) was 851.2 IU/mL. The HBsAg levels were reduced 150-fold when pegylated-interferon (Peg-IFN) α-2a was administered weekly for 48 weeks and did not increase during the rest period. Therefore, Peg-IFNα-2a was administered twice each week. During this time, HBsAg reached undetectable concentrations, and HBs antibody was detected and continued to be detectable during the three-year follow-up. These unprecedented findings suggest that IFN may contribute to the seroclearance of HBsAg in patients treated with NUCs.     

Prediction of response to entecavir therapy in patients with HBeAg-positive chronic hepatitis B based on on-treatment HBsAg, HBeAg and HBV DNA levels

Summary. Quantitative hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) assays are emerging as effective tools of on‐treatment predictors of response to antiviral agents, in addition to monitoring serum HBV DNA levels. However, the dynamic relationship between quantitative HBsAg, as well as HBeAg and HBV DNA, and the predictability of subsequent clinical outcomes during entecavir (ETV) therapy remain unclear. Eighty‐two patients with HBeAg‐positive chronic hepatitis B (CHB) received ETV therapy for ≥3 years. Virologic response (VR) after 3 years of ETV therapy was achieved in 73 (89.0%) patients. Among baseline and on‐treatment factors, on‐treatment HBV DNA levels performed better with respect to the prediction of response than HBsAg and HBeAg levels. Especially, the performance of absolute values of HBV DNA with respect to response was superior to HBV DNA decline from the baseline. The best predictive value was an absolute HBV DNA level of 2.3 log₁₀ IU/mL at month 6 (areas under the curve [AUROC], 0.977; 95% CI, 0.940–1.000; P < 0.001). HBeAg seroconversion after 3 years of therapy was achieved in 26 (31.7%) patients. On‐treatment HBeAg levels performed better with respect to the prediction of seroconversion than HBsAg and HBV DNA levels. The best cut‐off value for the HBeAg level at month 12 for the prediction of seroconversion was 0.62 log₁₀ PEIU/mL. Although the HBsAg level at baseline is often used to predict the antiviral potency of entecavir, on‐treatment HBV DNA and HBeAg levels are more helpful for prediction of subsequent clinical outcomes in HBeAg‐positive CHB patients with entecavir treatment.     

Loss of HBsAg antigen during treatment with entecavir or lamivudine in nucleoside‐naïve HBeAg‐positive patients with chronic hepatitis B*

Summary. This retrospective analysis was conducted to describe the characteristics of nucleoside‐naïve hepatitis B e antigen (HBeAg)‐positive patients with chronic hepatitis B, who achieved hepatitis B surface antigen (HBsAg) loss during entecavir or lamivudine therapy. HBeAg‐positive adults with chronic hepatitis B, elevated serum alanine aminotransferase, and compensated liver disease were randomized to double‐blind treatment for up to 96 weeks with entecavir 0.5 mg/day or lamivudine 100 mg/day. HBsAg and hepatitis B virus (HBV) DNA were measured at regular intervals during and off‐treatment follow‐up. Through a maximum duration of 96 weeks on‐treatment and 24 weeks off‐treatment, HBsAg loss was confirmed in 18/354 (5.1%) patients treated with entecavir and 10/355 (2.8%) patients treated with lamivudine. Among the 28 patients with confirmed HBsAg loss, 27 (96%) achieved HBV DNA <300 copies/mL, and 27 (96%) achieved confirmed HBeAg loss. All entecavir recipients with HBsAg loss had HBV DNA <300 copies/mL. Caucasian patients, and those infected with HBV genotype A or D, were significantly more likely to lose HBsAg. This retrospective analysis of data from a randomized, global phase three trial shows that confirmed loss of HBsAg occurred in 5% of nucleoside‐naïve HBeAg‐positive patients treated with entecavir, and that HBsAg loss is associated with sustained off‐treatment suppression of HBV DNA.     

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.     

Models for predicting hepatitis B e antigen seroconversion in response to interferon-α in chronic hepatitis B patients

AIM:To develop models to predict hepatitis B e antigen(HBe Ag)seroconversion in response to interferon(IFN)-αtreatment in chronic hepatitis B patients.METHODS:We enrolled 147 treatment-nave HBe Agpositive chronic hepatitis B patients in China and analyzed variables after initiating IFN-α1b treatment.Patients were tested for serum alanine aminotransferase(ALT),hepatitis B virus-DNA,hepatitis B surface antigen(HBs Ag),antibody to hepatitis B surface antigen,HBe Ag,antibody to hepatitis B e antigen(anti-HBe),and antibody to hepatitis B core antigen(anti-HBc)at baseline and 12 wk,24 wk,and 52 wk after initiating treatment.We performed univariate analysis to identify response predictors among the variables.Multivariate models to predict treatment response were constructed at baseline,12 wk,and 24 wk.RESULTS:At baseline,the 3 factors correlating most with HBe Ag seroconversion were serum ALT level4×the upper limit of normal(ULN),HBe Ag≤500 S/CO,and anti-HBc11.4 S/CO.At 12 wk,the 3 factors most associated with HBe Ag seroconversion were HBe Ag level≤250 S/CO,decline in HBe Ag1 log10 S/CO,and anti-HBc11.8 S/CO.At 24 wk,the 3 factors most associated with HBe Ag seroconversion were HBe Ag level≤5 S/CO,anti-HBc11.4 S/CO,and decline in HBe Ag2 log10 S/CO.Each variable was assigned a score of1,a score of 0 was given if patients did not have any of the 3 variables.The 3 factors most strongly correlating with HBe Ag seroconversion at each time point were used to build models to predict the outcome after IFN-αtreatment.When the score was 3,the response rates at the 3 time points were 57.7%,83.3%,and 84.0%,respectively.When the score was 0,the response rates were 2.9%,0.0%,and 2.1%,respectively.CONCLUSION:Models with good negative and positive predictive values were developed to calculate the probability of response to IFN-αtherapy.