Serum hepatitis B surface antigen levels predict treatment response to nucleos(t)ide analogues

HB Surface Antigen Level as a Useful Predictor for the Treatment Response to Tenofovir Alafenamide in Nucleoside Analogue Naïve Chronic Hepatitis B

AIM

To elucidate factors contributing to hepatitis B virus (HBV)-DNA clearance following tenofovir alafenamide (TAF) therapy in nucleoside analogue (NA) naïve patients with chronic hepatitis B (CHB) (n=92, 11 cirrhotic cases).

PATIENTS AND METHODS

The time interval between the start of TAF therapy and first confirmed undetectable HBV-DNA after TAF therapy was calculated. Univariate and multivariate analyses of factors related to undetectable HBV-DNA after TAF therapy were performed.

RESULTS

HB envelop antigen seropositivity was found in 12 patients (13.0%). The cumulative undetectable HBV-DNA rate at 1- and 2- year was 74.9% and 90.9%. In the multivariate Cox regression analysis of the undetectable HBV-DNA after TAF therapy, HBsAg level >1,000 IU/ml (p=0.0082, HBsAg level <100 IU/ml as a reference standard) was an independent predictor of the undetectable HBV-DNA after TAF therapy.

CONCLUSION

Baseline higher HBsAg level can be an adverse predictor for the undetectable HBV-DNA after TAF therapy in NA naïve CHB patients.

HBsAg Loss as a Treatment Endpoint for Chronic HBV Infection: HBV Cure

Despite the availability of effective vaccines and antiviral therapy over the past two to three decades, chronic hepatitis B virus (HBV) infection remains a major global health threat as a leading cause of cirrhosis and liver cancer. Functional HBV cure defined as hepatitis B surface antigen (HBsAg) loss and undetectable serum HBV DNA is associated with improved clinical outcomes in patients with chronic HBV infection. However, spontaneous loss of HBsAg is rare and occurs in only 1% of all HBsAg-positive individuals annually. Furthermore, the rate of functional cure with currently available antiviral therapy is even lower, <1% patients on treatment per year. Nonetheless, HBsAg loss has become the new target or therapeutic endpoint for antiviral treatment. Recently, there has been much excitement surrounding the development of novel antiviral agents such as small interfering RNA (siRNA), core assembly modulators (CAMs), nucleic acid polymers (NAPs) among others, which may be used in combination with nucleos(t)ide analogs and possibly immunomodulatory therapies to achieve functional cure in a significant proportion of patients with chronic hepatitis B. Novel assays with improved sensitivity for detection of very low levels of HBsAg and to determine the source of HBsAg production will also be required to measure efficacy of newer antiviral treatments for HBV cure. In this narrative review, we will define HBV cure, discuss various sources of HBsAg production, evaluate rates of HBsAg loss with current and future antiviral agents, review clinical factors associated with spontaneous HBsAg loss, and explore clinical implications of functional cure.

Analytical Performance of the Sysmex HISCL HBsAg Assay and Comparison with the Roche Elecsys HBsAg II Quant Assay in the Quantification of Hepatitis B Surface Antigen

Background and Objectives: This study aims to estimate the analytical performance of the Sysmex HISCL HBsAg assay and to assess the analytical correlation with the Roche Elecsys HBsAg II quant assay with clinical samples and the WHO International Standard (IS). Materials and Methods: The intra-assay precision, linearity, assay limitation, accuracy, and comparative evaluation of the HISCL HBsAg assay were estimated. Results: Extrapolating from the plot of the average total allowable error versus the reference value, an accuracy goal of 20% would be achieved around a limit of quantification (LoQ) of 0.014867 IU/mL. The percentage of biases for each level of the WHO IS measured by the two assays were less than 15%, except for the WHO 3rd IS, for which the HISCL HBsAg assay achieved a percentage of bias of 33%. In the comparative evaluation, Passing–Bablok regression analysis did not reveal any significant deviation from linearity between the two assays (y = −48.6998 + 1.9206x; p = 0.79 by the CUSUM test for linearity). The mean difference of the quantitative HBsAg level between the two assays was 1762.5 IU/mL in the Bland–Altman plot. Conclusions: The HISCL HBsAg assay, with a highly sensitive LoQ of 0.03 IU/mL, showed similar analytical performance in HBsAg quantification to the Elecsys HBsAg II quant assay and may be helpful in obtaining better diagnoses and therapeutic strategies for treating HBV infections.

Usefulness of a Hepatitis B Surface Antigen-Based Model for the Prediction of Functional Cure in Patients with Chronic Hepatitis B Virus Infection Treated with Nucleos(t)ide Analogues: A Real-World Study

In patients with chronic hepatitis B (CHB) under long-term treatment with nucleso(t)ide analogues (NAs), the loss of hepatitis B surface antigen (HBsAg) is a rare event. A growing body of evidence supports the use of quantitative HBsAg for the prediction of functional cure, although these results are mainly derived from studies performed on Asian patients with hepatitis B e antigen (HBeAg)-positive CHB. Here, we investigated the clinical role of quantitative HBsAg in a real-life cohort of CHB patients under treatment with NAs in a tertiary care center from North-West Italy. A total of 101 CHB patients (HBeAg-negative, n = 86) undergoing NAs treatment were retrospectively enrolled. HBsAg was measured at baseline (T0), 6 months (T1), 12 months (T2) and at the last follow-up (FU). Median FU was 5.5 (3.2–8.3) years; at the end of FU, 11 patients lost the HBsAg (annual incidence rate = 1.8%). Baseline HBsAg levels were significantly different between patients with no HBsAg loss and those achieving a functional cure (3.46, 2.91–3.97 vs. 1.11, 0.45–1.98 Log IU/mL, p < 0.001). Similarly, the HBsAg decline (Δ) from T0 to T2 was significantly different between the two groups of patients (0.05, −0.04–0.13, vs. 0.38, 0.11–0.80 Log IU/mL, p = 0.002). By stratified cross-validation analysis, the combination of baseline HBsAg and ΔHBsAg T0–T2 showed an excellent accuracy for the prediction of HBsAg loss (C statistic = 0.966). These results corroborate the usefulness of quantitative HBsAg in Caucasian CHB patients treated with antivirals for the prediction of HBsAg seroclearance.

The role of hepatitis B surface antibodies in HBV infection, disease and clearance

The clinical sequelae associated with chronic HBV infection is generally regarded as a consequence of an inadequate and inappropriate immune response to active viral replication, predominantly at the T-cell level. However, recent studies on hepatitis B surface antigen (HBsAg)-specific B cells and hepatitis B surface antibody (anti-HB) responses have identified their previously unrecognized role in the pathogenesis of chronic hepatitis B (CHB). These studies have also uncovered novel therapeutic approaches to more effectively target HBsAg loss and seroconversion, an important end point and regarded as a functional cure. Anti-HBs IgG has also been shown to have multiple direct acting antiviral roles with the Fab component directly blocking viral entry, and release while the Fc component has been linked to antibody dependent cellular cytotoxicity. Likewise, the HBsAg-specific B-cell dysfunctionality can be reversed providing new therapeutic opportunities to achieve functional cure in CHB.

Lowering the upper limit of serum alanine aminotransferase levels may reveal significant liver disease in the elderly

This study sought to determine the prevalence of significant liver disease in those subjects with serum alanine aminotransferase levels in the range between the current and the newly suggested upper limit of normal (termed the delta range). The files of the previous study subjects (who underwent at least one alanine aminotransferase measurement in 2002 and followed to 2012) were reviewed for a diagnosis of chronic liver disease; aspartate aminotransferase/platelet ratio index, FIB-4 and alanine aminotransferase/aspartate aminotransferase ratio were used to evaluate liver fibrosis. The prevalence of significant liver disease, by diagnoses and fibrosis scores was compared between subjects with alanine aminotransferase levels in the delta range (men, 42-45 IU/L; women, 26-34 IU/L) and in the newly suggested normal range (men, 15-42 IU/L; women, 10-26 IU/L). The cohort included 49,634 subjects (41% male, mean age 83±6 years) of whom 2022 were diagnosed with chronic liver disease including 366 with cirrhosis. Compared to subjects with alanine aminotransferase levels in the newly suggested normal range, subjects with alanine aminotransferase levels in the delta range had a significantly higher rate of chronic liver disease (men, 15.3% vs. 4.9%; women, 7.8% vs. 3.3%) and of cirrhosis specifically (men, 4.2% vs. 0.9%; women, 1.5% vs. 0.4%) and also had higher mean fibrosis scores (P <0.001 for all). Lowering the current upper limit of normal of serum alanine aminotransferase may help to identify elderly patients at risk of significant liver disease.

Circulating miR-122 Is a Predictor for Virological Response in CHB Patients With High Viral Load Treated With Nucleos(t)ide Analogs

Chronic hepatitis B (CHB) infection remains worldwide health problem. Antiviral treatment options for CHB patients include nucleos(t)ide analogs (NAs) and interferon. Most of the current biomarkers for predicting treatment response are virus-dependent. MicroRNA-122 is the most abundant liver-specific miRNA and has been identified involved in multiple liver physiology and pathology including hepatotropic virus infection. To identify the role of miR-122 in NA therapy, 80 CHB patients with high viral load (HVL) were enrolled and serum miR-122 levels at baseline, week 12 and week 24 were measured. Serum miR-122 levels were significantly lower in patients who developed virological response (VR), compared with non-VR group. Levels of miR-122 at week 12 and week 24 were determined to be independent prognostic indicators for a VR with satisfactory AUROC values at 0.812 and 0.800, respectively. During NA therapy, serum miR-122 level deceased steadily and an earlier reduction was observed in VR group, indicating early reduction of miR-122 level might increase the possibility of developing virological response. In conclusion, we identified the dynamic change of serum miR-122 level and miR-122 levels at week 12 and week 24 as independent predictors for VR in CHB patients with HVL treated with NAs.

Fully galactosyl-fucosyl-bisected IgG1 reduces anti-HBV efficacy and liver histological improvement

N-glycosylation on the crystallizable fragment (Fc) governs antibody-mediated immune responses. This study addressed the relevance of N-acetylglucosamine (GlcNAc)-bisected IgG₁ on the disease progression and treatment efficacy in the immune active phase of chronic hepatitis B virus (HBV) infection. Serum IgG₁N-glycan patterns from 166 HBV e antigen (HBeAg)-positive patients were analyzed using liquid chromatography-tandem mass spectrometry. The proportion of GlcNAc-bisected IgG₁ on the disease severity and efficacy of nucleos(t)ide analogue treatment were investigated. Cytokine-dependent regulations of IgG₁ GlcNAc bisection were also addressed using mouse IgG₁-producing hybridoma cells. We found that IgG₁ bearing a fully galactosyl-fucosyl-N-acetylglucosamine-bisected (G2FN) glycoform in HBeAg-positive patients was associated with high levels of HBV DNA or HBV surface antigen, alanine aminotransferase <2 upper limits of normal, and a mild liver injury. Moreover, baseline IgG₁-G2FN ≧ 1.5% was linked to lower probabilities of virological response (HBV DNA undetectable in serum), HBeAg seroconversion, HBV core antigen loss, and liver histological improvement after treatment. Cox and logistic regression analyses revealed that IgG₁-G2FN was an unfavorable factor for the virological response (hazard ratio = 0.620, 95% confidence interval = 0.466-0.825, P = 0.001) or liver histological improvement (odds ratio = 0.513, 95% confidence interval = 0.279-0.943, P = 0.032), respectively. Results from in vitro studies showed that transforming growth factor (TGF)-β1 treatment downregulated mannosyl β-1,4-N-acetylglucosaminyltransferase 3 and β-1,4-galactosyltransferase 1 activities and thereby IgG₁-G2FN production, and this phenomenon reflected an inverse correlation between IgG₁-G2FN and TGF-β1 in sera of patients (r = -0.431, P < 0.001). In conclusion, IgG₁-G2FN was related to an attenuated liver inflammation and unfavorable treatment responses in patients with HBeAg-positive chronic hepatitis B.

New and Old Biomarkers for Diagnosis and Management of Chronic Hepatitis B Virus Infection

Tests to detect the presence and activity of hepatitis B virus (HBV) are the cornerstones of diagnosis and management. Assays that detect or measure serum levels of HB surface antigen, HB surface antibody, and HB core antibody are used to identify patients with exposure to HBV, whereas other tests provide information on the level of virus replication, presence of specific variants, and presence of virus reservoirs. Newer diagnostic tests, used only in research settings so far, aim to quantify levels of intrahepatic HBV replication. Other tests have been developed to detect HBV infection in resource-limited settings. We review point-of-care tests (essential in global screening efforts), standard diagnostic tests used in routine clinical management, and newer tests that might be used in clinical trials of agents designed to cure HBV infection.

Taiwan consensus statement on the management of chronic hepatitis B

The experts of Taiwan Association for the Study of Liver (TASL) have actively participated and led the guidelines on hepatitis B virus (HBV) management by Asian Pacific Association for the Study of Liver (APASL) which is the first international association for the study of liver to publish the statement on HBV management before. However, there are more and more new data on the natural history and treatment of HBV infection in the past decade. These include new application of an old biomarker (quantitative HBsAg), clinical significance of HBV genotype and naturally occurring mutations, the role of non-invasive examination in evaluating severity of hepatic fibrosis, clinical significance of outcome calculators, new drug or new combination strategies towards more effective therapy and organ transplantation including liver and non-liver transplantation. It is time to publish the guidelines on HBV management of Taiwan. Hence, TASL have conducted an expert meeting to review, to discuss and to debate the relevant literatures, followed by draft the manuscript of HBV management guidelines and recommendations. The guidelines include general management, indications for fibrosis assessment, time to start or stop drug therapy, choice of drug to initiate therapy, when and how to monitor the patients during and after stopping drug therapy. Recommendations on the therapy of patients in special circumstances, including women in childbearing age, patients with antiviral drug resistance, concurrent viral infection, hepatic decompensation, patient receiving immune suppression or chemotherapy and patients in the setting of liver transplantation and hepatocellular carcinoma, are also included.

Viral Biomarkers in Chronic HBeAg Negative HBV Infection

Viral biomarkers are important tools for monitoring chronic hepatitis B virus (HBV) hepatitis B early antigen (HBeAg) negative infection, both in its natural course as well as during and after treatment. The biomarkers consist of antibodies against viral epitopes, viral proteins, and molecular surrogate markers of the quantity and transcriptional activity of the stable episomal HBV covalently closed circular DNA (cccDNA) which is located in the nuclei of the infected hepatocytes. HBV deoxyribonucleic acid (DNA) or else viral load measurement in plasma or serum is a marker of HBV replication of major clinical importance. HBV DNA is used for staging and treatment monitoring as described in international scientific guidelines. Quantification of HBV antigens, mainly hepatitis B surface antigen (HBsAg) as well as Hepatitis B core related antigen (HBcrAg), play an important yet secondary role, especially in cases of low or undetectable HBV DNA and has been evaluated for the classification of the inactive carrier state, as a predictor of subsequent HBsAg clearance, treatment outcome, and development of hepatocellular carcinoma (HCC). The measurement of the replicative intermediate HBV RNA in serum is currently evaluated and may also prove to be a significant biomarker particularly in patients treated with nucleot(s)ide analogs. This review focuses on the viral biomarkers mentioned above and their role in HBV, HBeAg negative, infection.

Relationship between serum quantitative HBsAg and HBV DNA levels in chronic hepatitis B patients

Serum hepatitis B surface antigen (HBsAg) level has been developed as an important marker to predict treatment outcome recent years. The authors aimed to identify the correlation between quantitative HBsAg and hepatitis B virus (HBV) DNA level in chronic hepatitis B (CHB) patients and explore whether quantitative HBsAg can be used as a surrogate marker of serum HBV DNA for CHB patients. One hundred seventy-three patients were included in this study. Patients were divided into two groups: Hepatitis B e antigen (HBeAg) positive and negative patients. There was a positive correlation between quantitative HBsAg and HBV DNA level in HBeAg positive patients (r = 0.509, P < 0.001) and poor correlation in HBeAg negative patients (r = 0.176, P = 0.096). Interestingly, completely no correlation (r = -0.01, P = 0.994) was found in younger HBeAg negative patients (<40 years old), whereas in older HBeAg negative patients (>40 years old) there is a positive correlation (r = 0.448, P = 0.003). Mean HBsAg titer and Alanine aminotransferase (ALT) level were significantly higher in HBeAg positive group (3.81 log₁₀ IU/mL; 105 IU/mL) than in negative group (2.85 log₁₀  IU/mL; 32 IU/mL) (P <  0.001). We concluded that quantitative HBsAg could reflect HBV DNA level in HBeAg positive patients, but could not surrogate for HBV DNA level in HBeAg negative patients. Our study improves understanding of the relationship between HBsAg titers and HBV DNA levels in CHB patient and may have implications for future treatment algorithms evaluating the HBsAg titers in both HBeAg positive and negative patients.

Current and future directions of management of hepatitis B: steps toward a cure

Universal hepatitis B virus vaccination has been effective in reducing incident chronic hepatitis B but will not have the requisite effect on the prevalence of end-stage liver disease in chronically infected persons. The natural history and immunological stages of hepatitis B virus infection are still being defined. Over three decades, current therapies have reduced morbidity from chronic hepatitis B. The majority require nucleoside analog maintenance therapy. The preferential preservation of covalently closed circular DNA (cccDNA), and capsid reverse transcriptase–cccDNA interactions currently precludes cure in most. A functional cure in  the host may require several synergistic antiviral and immunological intercessions. The correct sequencing and combinations of treatment with either host or viral targeting agents have yet to be determined. Proven surrogates for cccDNA for clinical trials are required. Different strategies may become apparent for patients at different stages of the disease. Curative therapies will require affordability. This review focuses on steps toward a cure.

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.

Quantification of HBsAg to predict low levels and seroclearance in HBeAg-negative patients receiving nucleos(t)ide analogues

BACKGROUND

HBeAg-negative chronic hepatitis B patients require long-term nucleos(t)ide analogues(NAs) because loss of surface antigen (HBsAg) is unusual. Low quantitative HBsAg (qHBsAg) levels can identify patients with higher probability of seroclearance. The aim of our study was to evaluate qHBsAg in HBeAg-negative patients receiving NAs to predict a reduction of HBsAg levels and seroclearance.

METHODS

Retrospective analysis of qHBsAg in HBeAg-negative patients before and at years 1, 3, 5, 8 and over of NAs treatment.

RESULTS

From 1999 to 2015, HBsAg was quantified in 358 serum samples from 95 HBeAg-negative patients. Low qHBsAg (<120 IU/mL) was identified at baseline or during follow-up in 14% of patients and HBsAg loss in 4%. No baseline variables predicted seroclearance and only treatment duration predicted low qHBsAg. The annual decline of qHBsAg was -0.102 log IU/mL and the median time to HBsAg loss was 6.04 years. The decline was greater in patients achieving low HBsAg levels (-0.257) than in those who did not (-0.057)(p<0.001). The diagnostic accuracy (ROC curve, 95%CI) of qHBsAg delta at year 3 was 0.89 (0.81-0.97), with cut-off >0.3 log IU/mL showing a positive and negative predictive value of 42% and 100% to identify patients achieving low levels of HBsAg.

CONCLUSIONS

Reduction of qHBsAg is slow in HBeAg-negative patients receiving NAs, although low levels or faster qHBsAg decline may occur in 14%. A qHBsAg reduction >0.3 log IU/mL at year 3 can identify patients with a higher probability of achieving low levels and HBsAg seroclearance.

Chronic hepatitis B patients with high liver fibrosis levels should receive antiviral treatment

The present study aimed to evaluate improvements in liver stiffness (LS) measured by transient elastography (TE) and associated factors in Chinese patients with chronic hepatitis B (CHB) treated with entecavir (ETV). A total of 190 consecutive CHB patients who received entecavir therapy and two LS measurements (LSMs) were enrolled in this retrospective study (average age, 47 years; 137 males [72.1%]), including 111 patients without liver cirrhosis (group 0) and 79 patients with liver cirrhosis (group 1). Each patient received LSM twice with an interval of six months. Normalized aspartate aminotransferase (AST) levels were accompanied by a significant reduction in LSM values (P<0.001) in each group. Multivariate analysis revealed that a higher initial LS value in groups 0 and 1, and a higher prothrombin time activity in group 1 was associated with a greater decline of the LS value. Higher initial quantitative hepatitis B surface antigen (qHBsAg) levels were correlated with a greater decline of the qHBsAg value in the two groups. In conclusion, LS values in CHB patients significantly improved after 24 weeks of entecavir therapy. The results suggested that higher LSM values at baseline contributed to a greater regression of LSM, and higher initial qHBsAg values could lead to greater qHBsAg reduction during ETV therapy. Extrapolating our results, we might be able to consider CHB patients who have higher initial LSM values or have higher levels of qHBsAg values when enrolled would have more benefit during ETV treatment.

Dynamic Characteristics of Serum Hepatitis B Surface Antigen in Chinese Chronic Hepatitis B Patients Receiving 7 Years of Entecavir Therapy

Background:

The ultimate goal of hepatitis B treatment is hepatitis B surface antigen (HBsAg) seroclearance. Several factors have been suggested to be associated with the rate of HBsAg reduction in antiviral-naive or lamivudine therapy cohorts. However, there are few studies evaluating the factors during long-term entecavir (ETV) therapy. In the present study, we aimed to evaluate the factors to predict the outcome of ETV therapy for 7 years.

Methods:

A total of 47 chronic hepatitis B (CHB) patients treated with ETV monotherapy were included in this study. Liver biochemistry, hepatitis B virus (HBV) serological markers, serum HBV DNA, and HBsAg titers were tested at baseline, 3 months, 6 months, and yearly from 1 to 7. The associations between factors and HBsAg reduction were assessed using multivariate tests with repeated measure analysis of variance.

Results:

At baseline, serum HBsAg levels showed a positive correlation with baseline HBV DNA levels (r = 0.625, P < 0.001). The mean HBsAg titers after ETV treatment were significantly lower than the baseline titers (P ranges from 0.025 to 0.000,000,6). The HBsAg reduction rate during the 1^st year was greater compared to after 1 year of treatment (P < 0.05). Multivariate test showed that hepatitis B e antigen (HBeAg) seroclearance and/or HBsAg reduction ≥0.5 log₁₀ IU/ml at 6 months had a high negative predictive value (96.77%) for HBsAg seroclearance (P = 0.002, P = 0.012, respectively).

Conclusions:

The HBsAg reduction rate during the 1^st year was greater than that after 1 year of treatment. Further, HBeAg status and HBsAg levels at month 6 are the optimal factors for the early prediction of HBsAg seroclearance after long-term ETV therapy in CHB patients.

Review of Laboratory Tests used in Monitoring Hepatitis B Response to Pegylated Interferon and Nucleos(t)ide Analog Therapy

There are only two currently approved classes of hepatitis B virus (HBV) antiviral agents, pegylated interferon (Peg-IFN), and nucleos(t)ide analogs (NAs) for chronic HBV infection. Although Peg-IFN is used for a finite 48-week duration and offers a greater chance of sustained off-treatment virological response, it is poorly tolerated and can only be offered to selected patients. The NAs are well tolerated but require prolonged therapy due to risk of relapse with treatment cessation. There is evolving data that novel virological assays (e.g., quantitative hepatitis B surface antigen, quantitative hepatitis B core antigen, quantitative antibody to core protein) in combination with hepatitis B genotype and more sensitive HBV DNA polymerase chain reaction (PCR) assays may be useful to predict response to IFN as well as off-treatment NA durability. Utilization of these clinical laboratory tests may be important given the development of novel anti-HBV therapies, hoping to achieve a cure for chronic hepatitis B infection.

The current treatment situation and definitions of a cure for chronic HBV infection

HBV vaccination, while effective in reducing incident chronic disease in endemic regions, will not have the desired impact on the rates of end-stage liver disease in chronically infected persons. Over three decades, IFN-α and nucleoside analogs have reduced the morbidity from the disease. A large reservoir of chronic infection remains. The natural history of HBV infection is still being defined. Understanding the interactions between HBV and the host will be fundamental to achieving higher rates of cure. Curing hepatitis B will require several steps for either eradication, or a functional cure in the host. It is unclear whether covently closed circular DNA chromatin would need to be cleared to cure hepatitis B, or whether low threshold levels would slow the disease.

Serum HBsAg level predicts response to antiviral treatment in patients with chronic hepatitis B

AIM: To dynamicly monitor serum hepatitis B surface antigen (HBsAg) levels in chronic hepatitis B patients receiving entecavir (ETV) to explore whether serum HBsAg level can predict the therapeutic effect of antiviral treatment.

METHODS: Ninety chronic hepatitis B patients were selected strictly and given ETV for one year. HBsAg and hepatitis B virus (HBV) DNA levels were determined at 0, 3, 6, 9, and 12 mo. The t-test, Pearson correlation, and receiver operating characteristic (ROC) curve were used for analysis.

RESULTS: A total of 52 (57.78%) patients showed a response to ETV treatment, and 38 (42.22%) did not. Age was significantly greater in the response group than in the non-response group, while HBsAg and HBV DNA levels were significantly lower in the response group (P < 0.05). HBsAg and HBV DNA levels were decreased in both groups, and the decreases were more significant in the response group (P < 0.05). HBsAg levels were significantly correlated with HBV DNA levels (r = 0.5353, P < 0.0001). The area under the ROC curve was lowest at 3 mo after treatment, followed by at baseline, at 6 mo, at 9 mo, and at 12 mo after treatment.

CONCLUSION: Serum HBsAg levels in patients with chronic hepatitis B can be used as a predictor of response to antiviral treatment.

[Is it possible to stop treatment with nucleos(t)ide analogs in patients with e-antigen negative chronic hepatitis B? Experience and new expectations]

BACKGROUND

Treatment of HBeAg-negative chronic hepatitis B (CHB) with nucleos(t)ide analogues (NA) is usually indefinite, since the loss of HBsAg, as a criterion for its discontinuation, is a rare event. Recent evidence suggests that discontinuing NA therapy may be feasible in selected patients.

OBJECTIVES

To analyze the rate of virological relapse in patients with HBeAg-negative CHB who discontinued treatment with NAs.

METHODS

We performed a single-center observational study that included 140 patients with HBsAg-negative CHB. Twenty-two patients, who received only NAs, discontinued treatment for different reasons and were subsequently monitored. All had normal ALT and AST, undetectable DNA and absence of cirrhosis or significant comorbidities before stopping treatment.

RESULTS

Twelve patients showed virologic relapse (54.54%). The mean interval between discontinuation and relapse was 6.38 months (± 1.9) (75% relapsed during the first 12 months after discontinuation). Five received adefovir, 1 lamivudine and adefovir, 1 tenofovir and 5 lamivudine alone. The mean treatment duration in this group was 38.5 months (± 4.5). The sustained response group had a higher mean age and longer treatment duration than patients with virologic relapse but these differences were not statistically significant.

CONCLUSIONS

The results suggest that NA treatment can be stopped in selected patients with CHB as long as they are not cirrhotic, have completed a minimum period of treatment, have normal ALT and sustained undetectable DNA. These patients should be closely monitored during the first year and then indefinitely.

Update on Hepatitis B Virus Infection: Focus on Treatment

This review article is an update of the current treatment strategies available for chronic hepatitis B. In addition to achieving on-therapy clinical remission and suppression of HBV replication without resistance, the ultimate goal of therapy is the development of sustained remission and HBsAg loss after discontinuation of treatment. This is the closest possible to cure outcome for hepatitis B virus (HBV) infection. These goals can be achieved by response-guided courses of pegylated interferon (peg-IFN)-alpha at rates higher than 30%, both in hepatitis B e antigen (HBeAg)-positive and HBeAg-negative patients. Review of the data regarding discontinuation of long term NA treatment in HBeAg-negative patients revealed that stopping such therapy is safe with high rates of sustained off treatment responses that appear to be immunologically induced. Decreasing hepatitis B surface antigen (HBsAg) titers under therapy to <500, particularly <100 IU/mL, and adding a course of peg-IFN to ongoing long term nucleos(t)ide analogue (NA) therapy increase the percentage of sustained responses following discontinuation of NA treatment.