Long-term hepatitis B surface antigen (HBsAg) kinetics during nucleoside/nucleotide analogue therapy: finite treatment duration unlikely

Caucasian Ethnicity, but Not Treatment Cessation is Associated with HBsAg Loss Following Nucleos(t)ide Analogue-Induced HBeAg Seroconversion

It is well appreciated that ethnicity influences the natural history and immune responses during a chronic hepatitis B infection. In this study, we explore the effect of ethnicity and treatment cessation on Hepatitis B surface Antigen (HBsAg) seroclearance in patients with Nucleos(t)ide Analogue (NA)-induced Hepatitis B e Antigen (HBeAg) seroconversion. We performed a multi-ethnic, multicentric observational cohort study. The analyzed cohort consisted of 178 mono-infected, predominantly male (75.3%) chronic hepatitis B patients of mixed ethnicity (44.4% Asians, 48.9% Caucasians) with nucleos(t)ide analogue-induced HBeAg seroconversion. Treatment was withdrawn in 105 patients and continued in 73, leading to HBsAg loss in 14 patients off- and 16 patients on-treatment, respectively. Overall, HBsAg loss rates were not affected by treatment cessation (hazard ratio 1.45, p = 0.372), regardless of consolidation treatment duration. Caucasian ethnicity was associated with an increased chance of HBsAg loss (hazard ratio 6.70, p = 0.001), but hepatitis B virus genotype was not (p = 0.812). In conclusion, ethnicity is the most important determinant for HBsAg loss after NA-induced HBeAg seroconversion, with up to six-fold higher HBsAg loss rates in Caucasians compared to Asians, irrespective of treatment cessation and consolidation treatment duration.

Monotherapy with tenofovir disoproxil fumarate for adefovir-resistant vs. entecavir-resistant chronic hepatitis B: A 5-year clinical trial

BACKGROUND & AIMS

Tenofovir disoproxil fumarate (TDF) monotherapy has displayed non-inferior efficacy to TDF plus entecavir (ETV) combination therapy in patients with hepatitis B virus (HBV) resistant to ETV and/or adefovir (ADV). Nonetheless, the virologic response rate was suboptimal in patients receiving up to 144 weeks of TDF monotherapy. We aimed to assess the efficacy and safety of TDF monotherapy given for up to 240 weeks.

METHODS

One trial enrolled patients with ETV resistance without ADV resistance (n = 90), and another trial included patients with ADV resistance (n = 102). Most patients (91.2%) also had lamivudine resistance. Patients were randomized 1:1 to receive TDF monotherapy or TDF + ETV combination therapy for 48 weeks, and then TDF monotherapy until week 240. We compared efficacy between the studies and safety in the pooled population at 240 weeks.

RESULTS

At week 240, the proportion of patients with serum HBV DNA <15 IU/ml was not significantly different between the ETV and ADV resistance groups in the full analysis set (84.4% vs. 73.5%; p = 0.07), which was significantly different by on-treatment analysis (92.7% vs. 79.8%; p = 0.02). Virologic blips associated with poor medication adherence occurred in 7 patients throughout the 240 weeks. None developed additional HBV resistance mutations. Among the 170 HBV e antigen (HBeAg)-positive patients at baseline, 12 (7.1%) achieved HBeAg seroconversion at week 240. None achieved HBV surface antigen seroclearance. Significant decreases from baseline were observed at week 240 in the estimated glomerular filtration rate (-3.21 ml/min/1.73 m² by the CKD-EPI equation, p <0.001) and bone mineral density (g/cm²) at the femur (-2.48%, p <0.001).

CONCLUSIONS

Up to 240 weeks of TDF monotherapy provided an increasing virologic response rate in heavily pretreated patients with HBV resistant to ETV and/or ADV. However, it was associated with poor serological responses and decreasing renal function and bone mineral density. (ClinicalTrials.gov No, NCT01639066 and NCT01639092).

LAY SUMMARY

In patients chronically infected with hepatitis B virus resistant to multiple drugs including lamivudine, entecavir, and/or adefovir, tenofovir disoproxil fumarate (TDF) monotherapy showed non-inferior efficacy compared with the combination therapy of TDF plus entecavir. Nonetheless, short-term TDF monotherapy was associated with suboptimal virologic response, and its long-term safety was uncertain. This study displayed that 240 weeks of TDF monotherapy provided a virologic response in most of those patients, but it was associated with poor serological responses and decreasing renal function and bone mineral density.

Stem Cell-Derived Hepatocyte-Like Cells as Model for Viral Hepatitis Research

Viral hepatitis, the leading cause of liver diseases worldwide, is induced upon infection with hepatotropic viruses, including hepatitis A, B, C, D, and E virus. Due to their obligate intracellular lifestyles, culture systems for efficient viral replication are vital. Although basic and translational research on viral hepatitis has been performed for many years, conventional hepatocellular culture systems are not optimal. These studies have greatly benefited from recent efforts on improving cell culture models for virus replication and infection studies. Here we summarize the use of human stem cell-derived hepatocyte-like cells for hepatotropic virus infection studies, including the dissection of virus-host interactions and virus-induced pathogenesis as well as the identification and validation of novel antiviral agents.

Sequential combination therapy with interferon, interleukin-2 and therapeutic vaccine in entecavir-suppressed chronic hepatitis B patients: the Endeavor study

BACKGROUND

Switching from nucleos(t)ide analogues to interferon (IFN) improves hepatitis B surface antigen (HBsAg) loss. We aimed to evaluate whether combining immunomodulators such as interleukin-2 (IL-2) and therapeutic vaccine with IFN enhances HBsAg loss in entecavir (ETV)-suppressed patients.

METHODS

Ninety-four patients exhibiting virological suppression and hepatitis B e antigen (HBeAg) loss following ETV treatment were randomized 1:1:1 to receive ETV (group I) or IFN (group II) for 48 weeks, or IFN and vaccine for 48 weeks plus IL-2 for 12 weeks (group III). The primary endpoint was HBsAg loss at week 48. Peripheral natural killer (NK) cells and regulatory T cells (Treg) were measured as immune checkpoint indicators.

RESULTS

Mean HBsAg decline at week 48 was significantly greater in group III (0.85 log 10 IU/mL) and group II (0.74 log 10 IU/mL), than in group I (0.13 log 10 IU/mL). At week 48, 9.38%, 3.03%, and 3.70% of subjects in group III, II, and I, respectively, achieved HBsAg loss. Among patients with baseline HBsAg titers ranging from 100 to 1500 IU/mL, HBsAg loss rate was 27.3, 7.1, and 0% in group III, II, and I, respectively. Responders in group III showed a significantly higher increase in CD56^bright CD16^-NK cells from week 24 to 36, and a significant decline in Treg from week 12 to 24 than non-responders.

CONCLUSION

For ETV-suppressed patients, particularly those with low baseline HBsAg levels, combination therapy with IFN and other immunomodulators may enhance HBsAg loss, while successful response correlates with partial restoration of NK cells and Tregs.

Okuda lecture: Challenges of hepatitis B in the era of antiviral therapy

Nucleos(t)ide analogs (NAs) are effective, safe, and convenient antiviral therapy to suppress replication of hepatitis B virus, which can be translated into improved long-term outcome of chronic hepatitis B patients. The current recommended first-line NAs, namely, entecavir and tenofovir, are largely free from problems of drug resistance. Nonetheless, there are still a few challenges in the era of NA. First, the risk of hepatocellular carcinoma can only be reduced but not eliminated, particularly among cirrhotic patients. For cirrhotic patients who have persistent low-level viremia on NA, that is, partial responders, the risk of hepatocellular carcinoma is higher than those with complete viral suppression. The best strategy to manage partial responders to entecavir or tenofovir is uncertain. Second, immune-tolerant patients are very difficult to treat with NA. A significant proportion of immune-tolerant patients will have detectable viremia despite a few years of continuous NA treatment, and the rate of hepatitis B e-antigen seroconversion is very low. Third, most patients need long-term treatment as NA cannot eliminate covalently closed circular DNA in the hepatocytes. Some patients can consider stop NA according to treatment guidelines, but viral and clinical relapses often occur after treatment cessation. There is no concrete consensus on when one should stop NA in a hepatitis B e-antigen-negative patient among different treatment guidelines. New biomarkers such as hepatitis B surface antigen level can be used to select patients to stop NA, but the data are still preliminary.

Hepatitis B surface antigen loss after discontinuing nucleos(t)ide analogue for treatment of chronic hepatitis B patients is persistent in White patients

OBJECTIVE

The objective of this study was to determine the long-term clinical outcome and persistence of hepatitis B surface antigen (HBsAg) loss after discontinuation of treatment.

BACKGROUND

The prognosis of patients with chronic hepatitis B (CHB) treated with nucleos(t)ide analogues (NAs) who discontinue treatment after loss of HBsAg remains largely unknown, particularly in White patients.

PATIENTS AND METHODS

We analysed a cohort of patients with CHB who discontinued NA treatment after loss of HBsAg. A total of 69 patients with hepatitis-B-e antigen-positive or hepatitis-B-e antigen-negative CHB with undetectable HBsAg during NA treatment were included after discontinuation of treatment, and followed up for a median period of 37.8 months (interquartile range: 23.8-54.6 months).

RESULTS

At the end of follow-up, none of the patients showed spontaneous reappearance of HBsAg and only one patient had detectable hepatitis B virus DNA (22 IU/ml). Another patient negative for HBsAg and anti-HBs developed hepatitis B virus reactivation without elevated transaminases after treatment with corticosteroids and vincristine for dendritic cell neoplasm, 38 months after withdrawal of the antiviral treatment. Regarding clinical outcome, a patient with cirrhosis developed hepatocellular carcinoma, 6.6 years after discontinuing treatment. None of the patients had hepatic decompensation or underwent liver transplantation.

CONCLUSION

HBsAg clearance after discontinuing NAs in patients with CHB is persistent and associated with good prognosis. The risk for developing hepatocellular carcinoma persists among patients with cirrhosis.

Add-on peginterferon alfa-2a to nucleos(t)ide analogue therapy for Caucasian patients with hepatitis B 'e' antigen-negative chronic hepatitis B genotype D

Nucleos(t)ide analogues (NAs) and peginterferon have complementary effects in chronic hepatitis B, but it is unclear whether combination therapy improves responses in genotype D-infected patients. We conducted an open-label study of peginterferon alfa-2a 180 μg/wk added to ongoing NA therapy in hepatitis B e antigen (HBeAg)-negative, genotype D-infected patients with hepatitis B virus DNA <20 IU/mL. The primary endpoint was proportion of patients with ≥50% decline in serum HBsAg by the end of the 48-week add-on phase. Seventy patients received treatment, 11 were withdrawn at week 24 for no decrease in HBsAg, and 14 withdrew for other reasons. Response rate (per-protocol population) was 67.4% (29/43) at week 48 (95% confidence interval [CI]: 51, 81) and 50.9% (28/55) at week 96 (95% CI: 38, 66). Median serum HBsAg decreased throughout peginterferon alfa-2a treatment and was significantly lower than baseline at weeks 48, 72 and 96 (P < 0.001). Decreases in HBsAg of ≥0.5-log10 and ≥1-log10 were documented in 19 (44.2%) and 6 (14.0%) patients at week 48 and 6 (10.9%) and 17 (30.9%) patients at week 96. The proportion of patients with HBsAg <1000, <500, <100 and <10 IU/mL at ≥1 timepoint during treatment was 78.6% (n = 44), 57.1% (n = 32), 21.4% (n = 12) and 7.1% (n = 4). Interferon gamma-induced protein 10 increased from baseline up to week 48, with week 12 levels significantly associated with response at week 48. Addition of peginterferon alfa-2a to ongoing NA therapy significantly decreased HBsAg levels in HBeAg-negative patients with genotype D infection (ClinicalTrials.gov NCT01706575).

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.

Combining hepatitis B core-related and surface antigens at end of nucleos(t)ide analogue treatment to predict off-therapy relapse risk

BACKGROUND

There remains an unmet need for convenient biomarkers to assess the risks of discontinuing nucleos(t)ide analogues (NAs) in chronic hepatitis B (CHB).

AIM

To investigate if hepatitis B core-related antigen (HBcrAg) is an independent of surface antigen (HBsAg) for risk prediction of NA cessation.

METHODS

This prospective multicentre study enrolled 135 CHB patients who stopped entecavir or tenofovir after achieving viral remission for a median of 25.2 months. All patients stopped NA with negative HBeAg and undetectable viral DNA, and were then observed for clinical relapse and HBsAg loss. Predictors including HBsAg and HBcrAg levels were explored using Cox proportional hazard model and weighted to develop a risk score.

RESULTS

During a median follow-up of 25.9 months, clinical relapse and HBsAg loss occurred in 66 and eight patients, respectively, with a 5-year cumulative incidence of 56.1% (95% CI 46.7-66.0%) and 8.8% (95% CI 4.3-17.4%), respectively. HBcrAg was an independent relapse predictor, as well as HBsAg, age, ALT and tenofovir use. A score (SCALE-B) was calculated by the equation of 35*HBsAg (log IU/mL) + 20*HBcrAg (log U/mL) + 2*age (year) + ALT (U/L) + 40 for tenofovir use. The concordance rates for clinical relapse were 0.87, 0.88, 0.87, 0.85 and 0.90 at 1, 2, 3, 4 and 5 years, respectively. Moreover, HBsAg loss occurred exclusively in low-risk patients predicted by the score.

CONCLUSIONS

Serum HBcrAg and HBsAg levels were independent predictors of off-NA relapse and can be factored into a risk score to guide treatment cessation in patients with CHB.

Long-term follow-up of patients treated with entecavir and peginterferon add-on therapy for HBeAg-positive chronic hepatitis B infection: ARES long-term follow-up

Addition of peginterferon alpha (PEG-IFN add-on) to entecavir (ETV) treatment after a short lead-in phase results in more response than ETV monotherapy in HBeAg-positive chronic hepatitis B infection (CHB). This study is the first to assess long-term efficacy of this treatment strategy. Patients who received ETV ± 24 weeks of PEG-IFN add-on in a global trial (ARES study) and completed follow-up were eligible to participate in this observational LTFU study if they had at least one combined HBeAg and HBV DNA measurement beyond week 96 of the ARES study. The primary endpoint was combined response (HBeAg loss and HBV DNA <200 IU/mL) at LTFU. In total, 48 patients treated with PEG-IFN add-on and 48 patients treated with ETV monotherapy were included. The median follow-up duration was 226 (IQR 51) weeks, and 86/96 (90%) patients were initial non-responders. At LTFU, combined response was present in 13 (27%) vs 11 (23%) patients (P = 0.81), and 1 log₁₀  HBsAg decline in 59% vs 28% (P = 0.02) for PEG-IFN add-on and ETV monotherapy, respectively. In 41 initial non-responders who continued ETV therapy, combined response at LTFU was present in 9 patients (PEG-IFN add-on: 5/22 [23%]; ETV monotherapy: 4/19 [21%]). Beyond week 96 of follow-up, rates of serological response became comparable between PEG-IFN add-on and ETV monotherapy. Although in this LTFU study initial non-responders were overrepresented in the add-on arm, PEG-IFN add-on possibly leads rather to accelerated HBeAg loss than to increased long-term HBeAg loss rates.

A genotype-specific baseline score predicts post-treatment response to peginterferon alfa-2a in hepatitis B e antigen-negative chronic hepatitis B

Background

Peginterferon alfa-2a induces durable responses in some hepatitis B e antigen-negative patients, but robust pretreatment predictors are not available to identify likely responders. In this study we aimed to develop genotype-specific baseline scoring systems to predict response.

Methods

Data from 323 hepatitis B e antigen-negative peginterferon alfa-2a recipients from three studies were analyzed. Scoring systems were developed using generalized additive models and multiple logistic regression analysis. Response was defined as hepatitis B virus DNA <2000 IU/mL alone (virological response) or in combination with alanine aminotransferase normalization (combined response) 48 weeks post-treatment.

Results

Points were assigned to genotype B/C patients for: age, alanine aminotransferase ratio, genotype B or C, and hepatitis B surface antigen level; and to genotype D patients for age, hepatitis B surface antigen level and hepatitis B virus DNA level. Higher total scores (range 0-5 for B/C; 0-3 for D) indicated a higher likelihood of response. Among genotype B/C patients with scores of 0-1, 2 and ≥3, respectively, virological response rates were 16.7%, 25.8% and 70.2%, and combined response rates were 12.5%, 21.0% and 57.4%. Among genotype D patients with scores of 0-1, 2 and 3, respectively, virological response rates were 10.1%, 28.0% and 50.0%, and combined response rates were 7.8%, 28.0% and 33.3%.

Conclusion

Genotype-specific baseline scoring systems can identify hepatitis B e antigen-negative patients with low or high likelihood of achieving sustained responses to peginterferon alfa-2a.

Entecavir add-on or switch-to pegylated interferon improves HBsAg clearance in HBe antigen negative chronic hepatitis B patients

Background and aims

Chronic hepatitis B (CHB) patients rarely achieve hepatitis B surface antigen (HBsAg) loss with nucleoside/nucleotide analog therapy.

Methods

In this retrospective study, it was evaluated that the rate of HBsAg loss in the HBe antigen negative (HBeAg⁻) patients (n=101) treated with entecavir (ETV) for ≥24 weeks followed by switching to (n=22) or adding on (n=26) pegylated interferon (PEG-IFN), and continuing ETV (n=53).

Results

HBsAg clearance rate at week 48 was 9% (2/22), 15% (4/26), and 0% (0/53) (P<0.05), in switch-to or add-on, or ETV monotherapy CHB patients, respectively. HBsAg reduction at week 48 was 1.182, 0.6614, or 0.056 log IU/mL, in switch-to, add-on, and ETV patients, respectively (P<0.001). The response rate (HBsAg reduction >1 log IU/mL at week 48) in the switch-to, add-on, and ETV monotherapy CHB patients was 60%, 40%, and 2%, respectively (P<0.001). In the switch-to and add-on patients, HBsAg reduction and clearance were associated with HBsAg titers at week 0 and HBsAg reduction at week 24. Furthermore, HBsAg reduction at week 24 was associated with the response rate at week 48 in the switch-to and add-on patients, showing that the area under the receiver operating characteristic curve was 0.904. Positive predictive value and negative predictive value for response rate was 70% and 100% with cut-off value 0.2 log IU/mL, respectively.

Conclusion

In summary, we demonstrated that PEG-IFN enhanced HBsAg loss in HBeAg⁻ CHB patients. High HBsAg clearance was achieved in the patients with HBsAg titers at baseline <1,000 IU/mL and HBsAg reduction >0.2 log IU/mL.

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.

Serum hepatitis B surface antigen correlates with fibrosis and necroinflammation: A multicentre perspective in China

The kinetics of serum hepatitis B surface antigen (HBsAg) during the natural history of hepatitis B virus (HBV) infection has been studied, but the factors affecting them remain unclear. We aimed to investigate the factors affecting HBsAg titres, using data from multicentre, large-sized clinical trials in China. The baseline data of 1795 patients in 3 multicentre trials were studied, and the patients were classified into 3 groups: hepatitis B early antigen (HBeAg)-positive chronic HBV infection (n = 588), HBeAg-positive chronic hepatitis B (n = 596), and HBeAg-negative chronic hepatitis B (n = 611). HBsAg titres in the different phases were compared, and multiple linear progression analyses were performed to investigate the implicated factors. HBsAg titres varied significantly in different phases (P = .000), with the highest (4.60 log10 IU/mL [10%-90% confidence interval: 3.52 log10 IU/mL-4.99 log10 IU/mL]) in patients with HBeAg-positive chronic HBV infection. In all phases, age and HBV DNA were correlated with serum HBsAg level. In HBeAg-positive chronic hepatitis B patients, a negative correlation between HBsAg titres and fibrosis stage was observed. Alanine amonitransferase or necroinflammatory activity was also correlated with HBsAg titres in HBeAg-negative chronic hepatitis B patients. In conclusion, decreased HBsAg titres may be associated with advancing fibrosis in HBeAg-positive chronic hepatitis B patients or increased necroinflammation in those with HBeAg-negative chronic hepatitis B. Our findings may help clinicians better understand the kinetics of HBsAg and provide useful insights into the management of this disease.

Deep sequencing identifies hepatitis B virus core protein signatures in chronic hepatitis B patients

BACKGROUND

We aimed to identify HBc amino acid differences between subgroups of chronic hepatitis B (CHB) patients.

METHODS

Deep sequencing of HBc was performed in samples of 89 CHB patients (42 HBeAg positive, 47 HBeAg negative). Amino acid types were compared using Sequence Harmony to identify subgroup specific sites between HBeAg-positive and -negative patients, and between patients with combined response and non-response to peginterferon/adefovir combination therapy.

RESULTS

We identified 54 positions in HBc where the frequency of appearing amino acids was significantly different between HBeAg-positive and -negative patients. In HBeAg negative patients, 22 positions in HBc were identified which differed between patients with treatment response and those with non-response. The fraction non-consensus sequence on selected positions was significantly higher in HBeAg-negative patients, and was negatively correlated with HBV DNA and HBsAg levels.

CONCLUSIONS

Sequence Harmony identified a number of amino acid changes associated with HBeAg-status and response to peginterferon/adefovir combination therapy.

HBsAg and HBcrAg as predictors of HBeAg seroconversion in HBeAg-positive patients treated with nucleos(t)ide analogues

HBeAg seroconversion marks an important spontaneous change and treatment end-point for HBeAg-positive patients and is a pre-requisite for HBsAg loss or functional cure. In this retrospective analysis, we aimed to identify predictors of seroconversion using serum quantitative HBsAg and HBcrAg, in HBeAg-positive patients treated with nucleos(t)ide analogues (NA). Data and samples from 118 HBeAg-positive adults (genotypes A-G) started on NA between Jan 2005 and Sept 2016 were retrospectively analysed at several time-points. The predictive power of on-treatment levels of HBsAg and HBcrAg was determined using receiver operating curve (ROC) analysis and cut-off values determined by maximized Youden's index. About 36.4% of patients achieved HBeAg seroconversion after a median of 39 months' treatment. On treatment kinetics of HBV DNA, HBsAg and HBcrAg differed between HBeAg seroconverters and nonseroconverters. A combination of HBsAg and HBcrAg had the greatest predictive value for HBeAg seroconversion: at 6 months, HBsAg of 3.9 log₁₀  IU/mL and HBcrAg of 5.7 log₁₀ U/mL had a sensitivity of 71.4%, specificity of 79.5%, positive predictive value (PPV) of 65.2% and negative predictive value (NPV) of 83.8%, with AUROC of 0.769 (0.668, 0.869; 95%CI), and at 12 months, HBsAg 3.8 log₁₀  IU/mL and HBcrAg 5.5 log₁₀ U/mL had a sensitivity of 73.7%, specificity of 79.5%, PPV of 63.6% and NPV of 86.1%, with AUROC 0.807 (0.713, 0.901; 95% CI). In conclusion, our results may be used to identify patients who are unlikely to achieve treatment end-points, which will be important as the future management of chronic hepatitis B looks to therapies that offer functional cure.

Incidence and predictors of hepatitis B surface antigen seroclearance after cessation of nucleos(t)ide analogue therapy in hepatitis B e antigen-negative chronic hepatitis B

Hepatitis B surface antigen (HBsAg) loss is a rare event during nucleos(t)ide analogue (Nuc) therapy. Limited data suggest that stopping Nuc therapy may increase HBsAg loss rate in hepatitis B e antigen-negative patients. A large study was conducted to investigate this issue in more detail. Of the 1,075 hepatitis B e antigen-negative patients treated with Nuc for a median of 156 (61-430) weeks, 5 showed HBsAg seroclearance during treatment at an estimated annual incidence of 0.15%. Of the patients who remained HBsAg-seropositive, 691 (52.3 years old, 86% male, 44.6% cirrhosis) had stopped Nuc therapy by the Asian-Pacific Association for the Study of the Liver stopping rule and then were prospectively followed up. Baseline and on-treatment clinical and viral features, treatment duration, consolidation duration, time to undetectable hepatitis B virus DNA, time to normal alanine aminotransferase, end-of-treatment HBsAg, and HBsAg log reduction were compared between patients with and without HBsAg seroclearance after end of treatment. During a median off-therapy follow-up period of 155 (2-614) weeks, HBsAg seroclearance was confirmed in 42 patients. The 6-year cumulative incidence was 13% with an estimated annual incidence of 1.78%. Cox regression analysis showed that shorter time to undetectable hepatitis B virus DNA (<12 weeks), greater HBsAg reduction during therapy (>1 log₁₀ ), lower end-of-treatment HBsAg level (<100 IU/mL), patients with sustained response, and relapsers not retreated were factors for off-therapy HBsAg seroclearance.

CONCLUSION

The incidence of HBsAg seroclearance after stopping Nuc was much higher than that during therapy and highest in patients without virologic and clinical relapse; patients with clinical relapse who remained untreated had a 7.34 times higher incidence of HBsAg clearance than those who received retreatment, suggesting that transient untreated clinical relapse may drive sufficient immune control to functional cure. (Hepatology 2017).

Integration of hepatitis B virus S gene impacts on hepatitis B surface antigen levels in patients with antiviral therapy

BACKGROUND AND AIM

The aim of this study is to investigate the impact of hepatitis B virus (HBV) S gene integration on serum hepatitis B surface antigen (HBsAg) levels in chronic hepatitis B with long-term nucleos(t)ide analogue (NUC) therapy.

METHODS

Chronic hepatitis B patients who performed liver biopsy at baseline and treated with long-term NUC therapy were recruited. The integration of HBV S gene in baseline liver biopsy specimen was detected by Alu polymerase chain reaction method. Serum HBsAg levels were measured at baseline and the second year and the fourth year after NUC therapy by Roche reagent, respectively. Serum HBsAg levels between HBV S gene integrated group and nonintegrated group were compared and analyzed.

RESULTS

Seventy patients were eligible for this study. Among them, 11 (15.7%) were found to have HBV S gene integration in their baseline liver biopsy specimens. Similar significant decrease of HBsAg levels was found in both integrated and nonintegrated groups (2.63 vs 2.65 log IU/mL, P = 0.478) after the first 2 years of NUC therapy. Thereafter, the decrease of HBsAg level from 2 to 4 years after therapy was largely unchanged in integrated group as compared with that of nonintegrated group (0.1 vs 2.53 log IU/mL, P = 0.002), with statistical difference.

CONCLUSIONS

Serum HBsAg could be originated from the expression of the integrated HBV S gene in patients with S gene integration, which implicated the limitations when regarding HBsAg as a surrogate biomarker of covalently closed circular DNA activity and as an indicator of safe NUC discontinuation.

Hepatitis B virus infection

Hepatitis B virus (HBV) is a hepatotropic virus that can establish a persistent and chronic infection in humans through immune anergy. Currently, 3.5% of the global population is chronically infected with HBV, although the incidence of HBV infections is decreasing owing to vaccination and, to a lesser extent, the use of antiviral therapy to reduce the viral load of chronically infected individuals. The course of chronic HBV infection typically comprises different clinical phases, each of which potentially lasts for decades. Well-defined and verified serum and liver biopsy diagnostic markers enable the assessment of disease severity, viral replication status, patient risk stratification and treatment decisions. Current therapy includes antiviral agents that directly act on viral replication and immunomodulators, such as interferon therapy. Antiviral agents for HBV include reverse transcriptase inhibitors, which are nucleoside or nucleotide analogues that can profoundly suppress HBV replication but require long-term maintenance therapy. Novel compounds are being actively investigated to achieve the goal of HBV surface antigen seroclearance (functional cure), a serological state that is associated with a higher remission rate (thus, no viral rebound) after treatment cessation and a lower rate of cirrhosis and hepatocellular carcinoma. This Primer addresses several aspects of HBV infection, including epidemiology, immune pathophysiology, diagnosis, prevention and management.

Drugs in Development for Hepatitis B

With high morbidity and mortality worldwide, there is great interest in effective therapies for chronic hepatitis B (CHB) virus. There are currently several dozen investigational agents being developed for treatment of CHB. They can be broadly divided into two categories: (1) direct-acting antivirals (DAAs) that interfere with a specific step in viral replication; and (2) host-targeting agents that inhibit viral replication by modifying host cell function, with the latter group further divided into the subcategories of immune modulators and agents that target other host functions. Included among the DAAs being developed are RNA interference therapies, covalently closed circular DNA (cccDNA) formation and transcription inhibitors, core/capsid inhibitors, reverse transcriptase inhibitors, hepatitis B surface antigen (HBsAg) release inhibitors, antisense oligonucleotides, and helioxanthin analogues. Included among the host-targeting agents are entry inhibitors, cyclophilin inhibitors, and multiple immunomodulatory agents, including Toll-like receptor agonists, immune checkpoint inhibitors, therapeutic vaccines, engineered T cells, and several cytokine agents, including recombinant human interleukin-7 (CYT107) and SB 9200, a novel therapy that is believed to both have direct antiviral properties and to induce endogenous interferon. In this review we discuss agents that are currently in the clinical stage of development for CHB treatment as well as strategies and agents currently at the evaluation and discovery phase and potential future targets. Effective approaches to CHB may require suppression of viral replication combined with one or more host-targeting agents. Some of the recent research advances have led to the hope that with such a combined approach we may have a functional cure for CHB in the not distant future.

48-Week Outcome after Cessation of Nucleos(t)ide Analogue Treatment in Chronic Hepatitis B Patient and the Associated Factors with Relapse

Background and Aims

We aimed to ascertain the feasibility and safety of NA cessation, the status of patients after cessation, and the predictive factors for relapse and subsequent retreatment.

Methods

A total of 92 patients were enrolled in this prospective study. Patients were monitored every month for the first 3 months after cessation and every 3 months thereafter.

Results

Sixty-two patients finished 48 weeks of follow-up. None died or developed liver failure, cirrhosis, or HCC. The 62 patients could be divided into 4 categories according to the 48-week clinical development of relapse. Virologic relapses occurred in 39 (62.9%) patients, with 72.7% occurring in the first 24 weeks in origin HBeAg positive patients and 82.4% in the first 12 weeks in origin HBeAg negative patients. Age (OR = 1.06, 95% CI = 1.02-1.10; p = 0.003), the HBsAg level (OR = 2.21, 95% CI = 1.47-3.32; p < 0.001), and positive origin HBeAg status (OR = 0.32, 95% CI = 0.14-0.74; p = 0.008) were predictive factors to virologic relapse. HBV DNA level (OR = 1.34, 95% CI = 1.13-1.58; p < 0.001) was predictive factor to retreatment.

Conclusions

NA cessation is safe under supervision. Age, HBsAg level, and origin HBeAg status can be predictive factors for virologic relapse. The study was submitted to ClinicalTrials.gov Protocol Registration and Results System with the assigned NCT ID NCT02883647.

Higher baseline viral diversity correlates with lower HBsAg decline following PEGylated interferon-alpha therapy in patients with HBeAg-positive chronic hepatitis B

Background

Viral diversity seems to predict treatment outcomes in certain viral infections. The aim of this study was to evaluate the association between baseline intra-patient viral diversity and hepatitis B surface antigen (HBsAg) decline following PEGylated interferon-alpha (Peg-IFN-α) therapy.

Patients and methods

Twenty-six HBeAg-positive patients who were treated with Peg-IFN-α were enrolled. Nested polymerase chain reaction (PCR), cloning, and sequencing of the hepatitis B virus S gene were performed on baseline samples, and normalized Shannon entropy (Sn) was calculated as a measure of small hepatitis B surface protein (SHBs) diversity. Multiple regression analysis was used to estimate the association between baseline Sn and HBsAg decline.

Results

Of the 26 patients enrolled in the study, 65.4% were male and 61.5% were infected with hepatitis B virus genotype B. The median HBsAg level at baseline was 4.5 log₁₀ IU/mL (interquartile range: 4.1–4.9) and declined to 3.0 log₁₀ IU/mL (interquartile range: 1.7–3.9) after 48 weeks of Peg-IFN-α treatment. In models adjusted for baseline alanine aminotransferase (ALT) and HBsAg, the adjusted coefficients (95% CI) for ΔHBsAg and relative percentage HBsAg decrease were −1.3 (−2.5, −0.2) log₁₀ IU/mL for higher SHBs diversity (Sn≥0.58) patients and −26.4% (−50.2%, −2.5%) for lower diversity (Sn<0.58) patients. Further analysis showed that the “a” determinant upstream flanking region and the first loop of the “a” determinant (nucleotides 341–359, 371–389, and 381–399) were the main sources of higher SHBs diversity.

Conclusion

Baseline intra-patient SHBs diversity was inverse to HBsAg decline in HBeAg-positive chronic hepatitis B (CHB) patients receiving Peg-IFN-α monotherapy. Also, more sequence variations within the “a” determinant upstream flanking region and the first loop of the “a” determinant were the main sources of the higher SHBs diversity.

High risk of hepatocellular carcinoma and death in patients with immune-tolerant-phase chronic hepatitis B

OBJECTIVE

High serum HBV DNA levels are associated with high risks of hepatocellular carcinoma (HCC) and cirrhosis in patients with chronic hepatitis B (CHB). Although the immune-tolerant (IT) phase is characterised by high circulating HBV DNA levels, it remains unknown whether antiviral treatment reduces risks of HCC and mortality.

DESIGN

This historical cohort study included HBeAg-positive patients with CHB with high HBV DNA levels (≥20 000 IU/mL) and no evidence of cirrhosis at a tertiary referral hospital in Korea from 2000 to 2013. The clinical outcomes of 413 untreated IT-phase patients with normal alanine aminotransferase (ALT) levels (females, <19 IU/mL; males, <30 IU/mL) were compared with those of 1497 immune-active (IA)-phase patients (ALT ≥80 IU/mL) treated with nucleos(t)ide analogues.

RESULTS

The IT group was significantly younger than the IA group (mean age, 38 vs 40 years at baseline, p=0.04). The 10-year estimated cumulative incidences of HCC (12.7% vs 6.1%; p=0.001) and death/transplantation (9.7% vs 3.4%; p<0.001) were significantly higher in the IT group than the IA group. In multivariable analyses, the IT group showed a significantly higher risk of HCC (HR 2.54; 95% CI 1.54 to 4.18) and death/transplantation (HR 3.38; 95% CI 1.85 to 6.16) than the IA group, which was consistently identified through inverse probability treatment weighting, propensity score-matched and competing risks analyses.

CONCLUSIONS

Untreated IT-phase patients with CHB had higher risks of HCC and death/transplantation than treated IA-phase patients. Unnecessary deaths could be prevented through earlier antiviral intervention in select IT-phase patients.

Responses are durable for up to 5 years after completion of peginterferon alfa-2a treatment in hepatitis B e antigen-positive patients

BACKGROUND

In the large randomised NEPTUNE study, peginterferon alfa-2a 180 μg/wk for 48 weeks produced higher hepatitis B e antigen (HBeAg) seroconversion rates 24 weeks post-treatment (36%) than a lower dose (90 μg/wk) and/or shorter duration (24 weeks) (range 14%-26%).

AIM

To determine seroconversion rates 5 years after completion of treatment in NEPTUNE.

METHODS

HBeAg-positive patients who completed 24 weeks' follow-up in NEPTUNE (with peginterferon alfa-2a 90 μg/wk × 24 weeks [group 1]; 180 μg/wk × 24 weeks [2]; 90 μg/wk × 48 weeks [3] or 180 μg/wk × 48 weeks [4]) were followed up.

RESULTS

Three hundred and eighty three of the 544 patients in the original study were enrolled in the long-term follow-up study. Many patients (196 overall; more in groups 1-3 than 4) received nucleos(t)ide analogues or immunomodulators during follow-up, and more patients had missing data at year 5 in groups 2 and 4 (48 weeks, 50/112) than in groups 1 and 3 (24 weeks, 23/103), which confounds the planned per-protocol analysis. HBeAg seroconversion rates in groups 1, 2, 3 and 4 at year 5 were 47.5%, 50.7%, 52.2% and 67.1%, respectively, (odds ratio for group 4 versus 1-3: 2.02; 95% CI 1.21, 3.38), using multiple imputation methods for missing measurements.

CONCLUSION

Seroconversion rates are durable for up to 5 years after completion of peginterferon alfa-2a therapy and, consistent with NEPTUNE, the results suggest that the licensed regimen (180 μg × 48 weeks) is more efficacious for HBeAg-positive patients than a lower dose and/or shorter treatment duration.

Increased NK Cell Function After Cessation of Long-Term Nucleos(t)ide Analogue Treatment in Chronic Hepatitis B Is Associated With Liver Damage and HBsAg Loss

BACKGROUND

Treatment with nucleos(t)ide analogues (NA) suppresses hepatitis B virus (HBV) DNA but rarely leads to functional cure of chronic hepatitis B (CHB). Following NA cessation, some hepatitis B e antigen (HBeAg)-negative CHB patients experience hepatitis B s antigen (HBsAg) loss. Cellular immune responses, including natural killer (NK) cell responses, explaining virological events following NA treatment cessation remain elusive.

METHODS

In a single-center prospective trial, 15 HBeAg-negative CHB patients on long-term NA treatment underwent structured NA cessation and were studied longitudinally. The NK cell compartment was assessed using high-dimensional flow cytometry and correlated with the clinical course.

RESULTS

Unsupervised stochastic neighbor embedding analysis revealed NA-treated CHB patients to have a significantly affected NK cell compartment compared to controls. Cessation of NA treatment resulted in minor phenotypic alterations, but it significantly augmented NK cell natural cytotoxicity responses in the CHB patients. This increased NK cell functionality correlated with alanine aminotransferase flares in the patients and was particularly enhanced in patients experiencing HBsAg seroclearance at long-term follow-up.

CONCLUSIONS

Increased NK cell function is associated with active hepatitis and HBsAg seroclearance following structured NA cessation. This adds to our knowledge of the immunological events that develop following cessation of NA treatment in CHB.

Trajectories of serum hepatitis B surface antigen kinetics in patients with chronic hepatitis B receiving long-term nucleos(t)ide analogue therapy

BACKGROUND & AIMS

The kinetics of serum hepatitis B surface antigen (HBsAg) levels during long-term nucleos(t)ide analogue (NA) therapy in chronic hepatitis B (CHB) patients remains unclear. We investigated the patterns of serum HBsAg kinetics and their association with therapeutic outcomes in genotype B- or C-infected CHB patients receiving long-term NA therapy.

METHODS

We enrolled 329 treatment-naive CHB patients receiving NA therapy for >5 years to analyse the kinetic patterns by using group-based trajectory models (GBTMs).

RESULTS

Most patients (82.4%) received entecavir therapy. The median treatment duration was 83.6 (68.5-89.7) months. The GBTMs revealed three groups for both the hepatitis B e antigen (HBeAg)-positive and -negative patients. The median annual decline in serum HBsAg levels during the first 5 years was significantly higher in Group 1 than in Groups 2 and 3 in HBeAg-positive (0.78 vs 0.10 vs 0.10 log₁₀ IU/mL) and HBeAg-negative (0.71 vs 0.08 vs 0.09 log₁₀ IU/mL) patients. HBsAg levels at the baseline and 12 months combined with an HBsAg decline from the baseline to 12 months of treatment predicted trajectory pattern 1 in HBeAg-positive (sensitivity, 77.8%; specificity, 99.1%; positive predictive value [PPV], 87.5%; and negative predictive value [NPV], 98.2%) and HBeAg-negative (sensitivity, 100%; specificity, 99.5%; PPV, 88.9%; and NPV, 100%) patients. The trajectory patterns were significantly associated with HBeAg loss in the HBeAg-positive patients and the achievement of HBsAg <100 IU/mL or HBsAg loss in HBeAg-positive and HBeAg-negative patients.

CONCLUSIONS

The trajectory of serum HBsAg levels predicts HBsAg loss in CHB patients receiving long-term NA therapy.

HBsAg Loss with Peg-interferon Alfa-2a in Hepatitis B Patients with Partial Response to Nucleos(t)ide Analog: New Switch Study

Background and Aims: Hepatitis B surface antigen (HBsAg) loss is seldom achieved with nucleos(t)ide analog (NA) therapy in chronic hepatitis B patients but may be enhanced by switching to finite pegylated-interferon (Peg-IFN) alfa-2a. We assessed HBsAg loss with 48- and 96-week Peg-IFN alfa-2a in chronic hepatitis B patients with partial response to a previous NA. Methods: Hepatitis B e antigen (HBeAg)-positive patients who achieved HBeAg loss and hepatitis B virus DNA <200 IU/mL with previous adefovir, lamivudine or entecavir treatment were randomized 1:1 to receive Peg-IFN alfa-2a for 48 (n = 153) or 96 weeks (n = 150). The primary endpoint of this study was HBsAg loss at end of treatment. The ClinicalTrials.gov identifier is NCT01464281. Results: At the end of 48 and 96 weeks' treatment, 14.4% (22/153) and 20.7% (31/150) of patients, respectively, who switched from NA to Peg-IFN alfa-2a cleared HBsAg. Rates were similar irrespective of prior NA or baseline HBeAg seroconversion. Among those who cleared HBsAg by the end of 48 and 96 weeks' treatment, 77.8% (14/18) and 71.4% (20/28), respectively, sustained HBsAg loss for a further 48 weeks. Baseline HBsAg <1500 IU/mL and week 24 HBsAg <200 IU/mL were associated with the highest rates of HBsAg loss at the end of both 48- and 96-week treatment (51.4% and 58.7%, respectively). Importantly, extending treatment from 48 to 96 weeks enabled 48.3% (14/29) more patients to achieve HBsAg loss. Conclusions: Patients on long-term NA who are unlikely to meet therapeutic goals can achieve high rates of HBsAg loss by switching to Peg-IFN alfa-2a. HBsAg loss rates may be improved for some patients by extending treatment from 48 to 96 weeks, although the differences in our study cohort were not statistically significant. Baseline and on-treatment HBsAg may predict HBsAg loss with Peg-IFN alfa-2a.

Long-Term Follow-up and Quantitative Hepatitis B Surface Antigen Monitoring in North American Chronic HBV Carriers

INTRODUCTION

Quantitative hepatitis B surface antigen (qHBsAg) combined with HBV DNA may be useful for predicting chronic hepatitis B (CHB) activity and nucleoside analogue (NA) response.

MATERIAL AND METHODS

In this retrospective cohort study we evaluated qHBsAg levels according to CHB disease phase and among patients on treatment. Random effect logistic regression analysis was used to analyze qHBsAg change with time in the NA-treated cohort.

RESULTS

545 CHB carriers [56% M, median age 48 y (IQR 38-59), 73% Asian] had qHBsAg testing. In the untreated group (44%), 8% were classified as immune tolerant, 10% immune clearance, 40% inactive, and 43% had HBeAg- CHB and the median HBsAg levels were 4.6 (IQR 3.4-4.9), 4.0 (IQR 3.4-4.5), 2.9 (IQR 1.4-3.8), and 3.2 log IU/mL (IQR 2.6-4.0), respectively; p < 0.001. In the NA-treated group (28% entecavir, 68% tenofovir, 4% lamivudine), no significant change in qHBsAg levels occured with time. However, 19% of patients on long-term NA had sustained qHBsAg < 2 log10 IU/mL.

CONCLUSION

qHBsAg titers were associated with CHB phase and remained stable in those on long-term NA. A significant number of treated patients had low-level qHBsAg, of which some may be eligible for treatment discontinuation without risk of flare.

Impact of integrated viral DNA on the goal to clear hepatitis B surface antigen with different therapeutic strategies

A hallmark of hepatitis B virus (HBV) infection is the presence of hepatitis B surface antigen (HBsAg) in the serum of patients. Sustained loss of HBV DNA and HBsAg from the blood are main goals for treatment, and considered as functional cure. It is rarely achieved with long-term nucleoside analogue treatment though, both because cccDNA, the template for viral replication, is not completely cleared, and probably also because hepatocytes with HBV DNA integrated into their chromosomes persist and continue to produce large amounts of HBsAg. Therefore, loss of HBsAg requires that both cccDNA and integrated DNA are cleared or their expression blocked. Recent data indicate that this may be achieved in some patients by stopping nucleoside analogue treatment, and that HBsAg-levels can be reduced by using specific interfering RNA. In the future, targeted degradation or disruption of HBV DNA might be possible using genome editing techniques such as CRISPR/Cas9.

Clinical utility of hepatitis B surface antigen kinetics in treatment-naïve chronic hepatitis B patients during long-term entecavir therapy

AIM

To investigate the utility of hepatitis B surface antigen (HBsAg) kinetics in chronic hepatitis B patients during long-term entecavir treatment.

METHODS

This retrospective study included treatment-naïve chronic hepatitis B patients who received at least 2 years of consecutive entecavir treatment. Patients were followed up at three to six month intervals with liver biochemistry, hepatitis B virus DNA, and abdominal sonography. In hepatitis B e antigen (HBeAg)-positive patients, HBeAg levels were assessed every three to six month until results became negative. Serum HBsAg levels were determined at the baseline, one-year and five-year time points. Liver cirrhosis was diagnosed through liver biopsy, imaging examinations, or clinical findings of portal hypertension. Hepatocellular carcinoma was diagnosed by histological examination or dynamic image studies.

RESULTS

A total of 211 patients were enrolled. The median treatment time was 5.24 (2.00-9.62) years. Multivariate analysis showed that lower baseline HBsAg levels were associated with an earlier virological response, earlier hepatitis B e antigen (HBeAg) seroconversion, and earlier biochemical response in HBeAg-positive patients (cut-off value: 4 log IU/mL) and an earlier virological response in HBeAg-negative non-cirrhotic patients (cut-off value: 2.4 log IU/mL). Although HBsAg levels decreased slowly during long-term entecavir treatment, higher HBsAg decrease rates were found in the first year for HBeAg-positive non-cirrhotic patients, and patients with higher baseline HBsAg levels. More favorable clinical outcomes were not observed by a rapid HBsAg decline per se, but depended on lower baseline HBsAg levels.

CONCLUSION

Baseline HBsAg can be used to predict treatment responses. HBsAg levels and decrease rates should be considered together according to disease status while interpreting HBsAg changes.

Tenofovir disoproxil fumarate monotherapy is superior to entecavir-adefovir combination therapy in patients with suboptimal response to lamivudine-adefovir therapy for nucleoside-resistant HBV: a 96-week prospective multicentre trial

BACKGROUND

A complete virological response is closely related to the long-term outcome of patients with chronic hepatitis B and prevention of emerging HBV mutations. We aimed to evaluate the efficacy of tenofovir disoproxil fumarate (TDF) monotherapy compared to entecavir-adefovir dipivoxil (ETV-ADV) combination therapy in patients with suboptimal responses to long-term lamivudine-adefovir dipivoxil (LAM-ADV) therapy for nucleoside analogue-resistant chronic hepatitis B.

METHODS

Patients (n=60) were randomized to TDF monotherapy or ETV-ADV combination therapy for 96 weeks. All patients had the rt204I/V mutation and serum HBV DNA was measured (>60 IU/ml) during LAM-ADV therapy. The primary end point was a complete virological response (HBV DNA <20 IU/ml) at week 96.

RESULTS

The median duration of prior LAM-ADV rescue therapy was 43 (7-108) months. A complete virological response was achieved in 86.6% and 53.3% of patients in the TDF and ETV-ADV groups, respectively, at week 96 (P=0.005). Reduction in serum HBV DNA was significantly greater in the TDF group than in ETV-ADV group (-3.2 ±1.2 versus -2.6 ±1.2; P=0.01). Hepatitis B e antigen loss (22.2% versus 16.6%; P=0.731) and biochemical responses (76.7% versus 73.3%; P=0.766) were not different between the TDF and ETV-ADV groups. No newly emerged mutations were detected. Both therapies demonstrated favourable safety profiles.

CONCLUSIONS

TDF therapy achieved a better complete virological response than ETV-ADV therapy in chronic hepatitis B patients with suboptimal response to long-term LAM-ADV rescue therapy. (KCT0000627).

Pronounced decline of serum HBsAg in chronic hepatitis B patients with long-term effective nucleos(t)ide analogs therapy

AIMS

This study aims to investigate the kinetics of serum HBsAg levels in chronic hepatitis B patients with long-term nucleos(t)ide analogs (NAs) therapy.

METHODS

This was a retrospective clinical study. Serum HBsAg in serial samples of 94 patients, who received at least 8 years of NAs therapy, were measured using Elecsys® HBsAg II Quant Assay.

RESULTS

In this cohort, serum HBsAg levels reduced from 3.80 log10 IU/mL at baseline to 2.72 log10 IU/mL at year 8 (p < .001), and the percentage of patients with HBsAg <1000 IU/mL increased from 14.9% at baseline to 55.3% at year 8 (p < .001). The reduction of serum HBsAg did not differ significantly between patients stratified by baseline virological parameters and type of antiviral agents. But as compared to patients without HBeAg seroconversion, HBsAg levels were significant lower in patients with HBeAg seroconversion (3.19 vs. 2.47 log10 IU/mL at year 8, p = .001). As compared to patients with slow (0-1 log10 IU/mL) or steady HBsAg(≤0 log10 IU/mL) decline at year 1, patients with a rapid HBsAg (≥1 log10 IU/mL) decline had a significantly lower HBsAg levels from year 2 to 8. However, Cox regression analysis showed that only absolute HBsAg levels at year 1 was an independent predictor of subsequent HBsAg <1000 IU/mL at year 8 of antiviral therapy(HR 0.242, p = .004).

CONCLUSION

Pronounced HBsAg declines could be achieved in patients after long-term effective therapy with NAs, and on-treatment low serum HBsAg level at year 1 might be a predictor of serum HBsAg <1000 IU/mL at year 8.

Switching to PegIFNα-2b leads to HBsAg loss in patients with low HBsAg levels and HBV DNA suppressed by NAs

Patients with low hepatitis B surface antigen (HBsAg) levels and hepatitis B virus (HBV) DNA suppression by nucleos(t)ide analogues (NAs) achieve high rate of HBsAg loss through switching to PegIFNα in pre-registration study. The aim of this study was to achieve higher rate of HBsAg loss through extended PegIFN treatment. 98 patients with HBsAg < 2,000 IU/ml and HBV DNA < 20 IU/ml were randomized to receive PegIFNα-2b or continuing NA therapy for 60 weeks. At the end of treatment (EOT) and end of follow-up (EOF), only patients who switched to PegIFNα-2b achieved HBsAg loss (32.6%) and HBsAg seroconversion (27.9% and 25.6%). Patients who switched to PegIFNα-2b also achieved higher HBeAg seroconversion rates (65.1%) and HBeAg loss (81.4% and 90.7%) than those who continued NAs treatment. On-treatment HBsAg declines predicted the responses at EOT, and HBsAg declines at post-baseline times predicted the responses at EOF. The rates of responses were not increased through extended PegIFNα treatment. For patients with low HBsAg and HBV suppression with NAs, switching to PegIFNα-2b significantly increased the rates of HBsAg loss and HBsAg seroconversion. HBsAg decline can predict the response of switching to PegIFNα-2b following from NAs.

Monotherapy with tenofovir disoproxil fumarate for multiple drug-resistant chronic hepatitis B: 3-year trial

Combination therapy has been recommended for the treatment of patients harboring multiple drug-resistant hepatitis B virus (HBV). However, we recently demonstrated that monotherapy with tenofovir disoproxil fumarate (TDF) for 48 weeks displayed noninferior efficacy to TDF plus entecavir (ETV) combination therapy in patients with HBV resistant to multiple drugs, including ETV and adefovir. Nonetheless, whether prolonged TDF monotherapy would be safe and increase the virologic response rate in these patients was unclear. Among 192 patients with HBV-resistance mutations to ETV and/or adefovir, who were randomized to receive TDF monotherapy (n = 95) or TDF/ETV combination therapy (n = 97) for 48 weeks, 189 agreed to continue TDF monotherapy (TDF-TDF group) or to switch to TDF monotherapy (TDF/ETV-TDF group) and 180 (93.8%) completed the 144-week study. Serum HBV DNA <15 IU/mL at week 48, the primary efficacy endpoint, was achieved in 66.3% in the TDF-TDF group and 68.0% in the TDF/ETV-TDF group (P = 0.80). At week 144, the proportion with HBV DNA <15 IU/mL increased to 74.5%, which was significantly higher compared with that at week 48 (P = 0.03), without a significant difference between groups (P = 0.46). By on-treatment analysis, a total of 79.4% had HBV DNA <15 IU/mL at week 144. Transient virologic breakthrough occurred in 6 patients, which was due to poor drug adherence. At week 144, 19 patients who had HBV DNA levels >60 IU/mL qualified for genotypic resistance analysis, and 6 retained some of their baseline resistance mutations of HBV. No patients developed additional resistance mutations throughout the study period.

CONCLUSION

TDF monotherapy was efficacious and safe for up to 144 weeks, providing an increasing rate of virologic response in heavily pretreated patients with multidrug-resistant HBV. (Hepatology 2017;66:772-783).

Smaller reduction of hepatitis B virus DNA in liver tissue than in serum in patients losing HBeAg

The prognosis and outcome of treatment for chronic hepatitis B virus (HBV) infection are predicted by levels of HBV DNA in serum. These levels are composed of relaxed circular DNA (rcDNA) and double stranded linear DNA in viral particles, whereas, HBV DNA in liver tissue also can be covalently closed circular DNA (cccDNA) or integrated into the human genome. The aim of this study was to investigate the quantitative relation between HBV DNA in serum and tissue, its change over time and how these markers relate to serum levels of hepatitis B surface antigen (HBsAg). Serum and liver biopsies taken from 15 patients with chronic HBV infection on two occasions during 2.7-11.1 years were analyzed retrospectively. At baseline, the median HBV DNA levels in serum were 7.76 log₁₀  IU/mL in nine hepatitis B e antigen (HBeAg) positive and 3.65 log₁₀ IU/mL in six HBeAg-negative patients. At follow-up, serum HBV DNA, serum HBsAg, and intrahepatic HBV DNA (ihDNA) levels had declined by 4.36, 0.52, and 1.47 log₁₀ units, respectively, in seven patients that lost HBeAg, whereas the corresponding reductions were 0.36, 0.30, and 0.39 log₁₀ units in eight patients with unchanged HBeAg status. We conclude that HBV DNA in liver tissue declined almost 1000 times less than HBV DNA in serum during and after loss of HBeAg. This finding raises the possibility that integrated sequences constitute a significant part of the ihDNA. Alternatively, the greater decline of HBV DNA in serum might be due to yet unknown mechanisms acting downstream of reverse transcription.

Plasma MicroRNA Levels Are Associated With Hepatitis B e Antigen Status and Treatment Response in Chronic Hepatitis B Patients

Background

Hepatitis B virus (HBV) modulates microRNA (miRNA) expression to support viral replication. The aim of this study was to identify miRNAs associated with hepatitis B e antigen (HBeAg) status and response to antiviral therapy in patients with chronic hepatitis B (CHB) , and to assess if these miRNAs are actively secreted by hepatoma cells.

Methods

Plasma miRNA levels were measured by reverse-transcription quantitative polymerase chain reaction in healthy controls (n = 10) and pretreatment samples of an identification cohort (n = 24) and a confirmation cohort (n = 64) of CHB patients treated with peginterferon/nucleotide analogue combination therapy. Levels of HBV-associated miRNAs were measured in cells, extracellular vesicles, and hepatitis B surface antigen (HBsAg) particles of hepatoma cell lines.

Results

HBeAg-positive patients had higher plasma levels of miR-122-5p, miR-125b-5p, miR-192-5p, miR-193b-3p, and miR-194-5p compared to HBeAg-negative patients, and levels of these miRNAs were associated with HBV DNA and HBsAg levels. Pretreatment plasma levels of miR-301a-3p and miR-145-5p were higher in responders (combined response or HBsAg loss) compared to nonresponders. miR-192-5p, miR-193b-3p, and miR-194-5p were present in extracellular vesicles and HBsAg particles derived from hepatoma cells.

Conclusions

We identified miRNAs that are associated with HBeAg status, levels of HBV DNA and HBsAg, and treatment response in CHB patients. We demonstrated that several of these miRNAs are present in extracellular vesicles and HBsAg particles secreted by hepatoma cells.

Predictors for efficacy of combination therapy with a nucleos(t)ide analogue and interferon for chronic hepatitis B

This study aims to explore the efficacy of interferon-α (IFN-α) combined with either entecavir (ETV) or adefovir (ADV) therapy versus IFN-α mono-therapy for chronic hepatitis B (CHB) patients, and to identify the factors associated with treatment outcomes. Totally, 159 CHB patients receiving interferon-based treatment for 48 weeks were enrolled in this retrospective study, including IFN-α mono-therapy group (group A, n=44), IFN-α plus ADV group (group B, n=53) and IFN-α plus ETV group (group C, n=62). The primary measures of efficacy assessments were the changes in HBsAg. Cox regression analysis was used to identify the predictors of treatment outcomes. The predictive values of the factors were assessed by ROC analysis. For patients with baseline hepatitis B surface antigen (HBsAg) level <1000 IU/mL, the reductions in mean HBsAg levels at week 48 were greater in group C than that in group A (P<0.05). Higher rate of HBeAg seroconversion was achieved in the combined therapy group than in IFN-α mono-therapy group at week 48 (P<0.05). Two factors were independently associated with HBeAg seroconversion: baseline HBeAg level <2.215 log10 index/mL and ΔHBeAg (decline in HBeAg from baseline) >0.175 log10 at week 12. In conclusion, interferon-α plus ETV therapy can accelerate HBsAg decline as compared with interferon-α mono-therapy in CHB patients with lower baseline HBsAg levels, and the combination therapy was superior to IFN-α mono-therapy in increasing the rate of HBeAg seroconversion. Baseline HBeAg and ΔHBeAg at week 12 can independently predict HBeAg seroconversion in patients subject to interferon-based therapy for 48 weeks.

Serum viral load at the virological relapse predicts subsequent clinical flares in chronic hepatitis B patients off entecavir therapy

BACKGROUND AND AIM

Therapeutic duration of nucleos(t)ide analogues for chronic hepatitis B (CHB) is not indefinite in many parts of the world. Viral reactivation is common off therapy, but the risk of subsequent clinical outcome remains unclear and unpredictable. We aimed to quantify the incidence of and explore the predictors for clinical flare following virological relapse in CHB patients who discontinue entecavir therapy.

METHODS

This multicenter cohort study prospectively monitored 133 CHB patients who were HBeAg-negative and viral DNA-undetectable when discontinuing entecavir after at least 3 years on therapy. Following virological relapse (viral DNA >2,000 IU/mL) that occurred in 92 patients, the incidences of subsequent clinical flare and persistent (unremittent for 3 months) or severe hepatitis (with jaundice or coagulopathy) were determined, and risk factors were explored. Patients did not resume antiviral therapy until occurrence of persistent or severe hepatitis.

RESULTS

The cumulative incidence of clinical hepatitis 2 years after virological relapse was 61.0% (95% confidence interval [CI], 49.9-72.3%) and that of persistent or severe hepatitis was 53.0% (95% CI, 40.9-66.2%). Serum viral load at the virological relapse was associated with both clinical hepatitis (adjusted hazard ratio [HR], 1.31 per log IU/mL; 95% CI, 1.07-1.60) and persistent or severe hepatitis (adjusted HR, 1.63 per log IU/mL; 95% CI, 1.27-2.10), after adjustment for serum aminotransferase and alfa-fetoprotein levels in the multivariate analysis. Viral DNA >100 000 IU/mL predicted a nearly inevitable occurrence of clinical flare (P < 0.0001).

CONCLUSIONS

A high viral load at the virological relapse predicts subsequent clinical hepatitis in CHB patients who discontinue entecavir.

Hepatitis B surface antigen reduction by switching from long-term nucleoside/nucleotide analogue administration to pegylated interferon

Hepatitis B surface antigen (HBsAg) reduction during nucleoside/nucleotide analogue (NA) therapy is slow and an alternative strategy for patients receiving ongoing NA to facilitate HBsAg reduction is required. We investigated whether switching to pegylated interferon (PEG-IFN) after long-term NA administration enhances HBsAg reduction. Forty-nine patients who switched from long-term NA to 48 weeks of PEG-IFN alfa-2a were studied. The mean duration of previous NA was 48 months (sequential group). A total of 147 patients who continued NA and matched for baseline characteristics were analysed for comparison (NA continuation group). The treatment response was defined as HBsAg reduction ≥1.0 logIU/mL at the end of PEG-IFN. HBsAg reduction at week 48 was 0.81±1.1 logIU/mL in the sequential group, which was significantly higher than that in the NA continuation group (0.11±0.3 logIU/mL, P < .001). The treatment response was achieved in 29% and 2% of the sequential group and NA continuation group (P < .001), and the odds ratio of sequential therapy for the treatment response was 19 compared with the NA continuation (P < .001). In patients tested positive for hepatitis B e antigen (HBeAg), HBeAg seroconversion was higher in the sequential group (44% vs 8%, P < .001). In HBeAg-negative patients, only patients in the sequential group achieved HBsAg loss. No patient needed to resume NA administration because of HBV DNA increase accompanied by alanine aminotransferase flares. In summary, sequential therapy with PEG-IFN after long-term NA enhances the reduction of HBsAg and may represent a treatment option to promote HBsAg loss.

The role of peginterferon in nucleos(t)ide-analogue-treated chronic hepatitis B patients: A review of published literature

Chronic hepatitis B infection (CHB) causes up to 1.0 million deaths annually. Currently, more than 90% of CHB patients worldwide are receiving indefinite nucleos(t)ide analogue (NA) therapy. New strategies for optimizing hepatitis B surface antigen (HBsAg) loss are required for NA-treated patients as the majority are unable to achieve HBsAg loss and may require lifelong therapy. In hepatitis B e antigen (HBeAg)-positive patients, switching from NAs to finite peginterferon (PegIFN) therapy can double HBeAg seroconversion rates. One in five patients who switch to PegIFN can achieve HBsAg loss, whereas patients who continue NA therapy typically do not. In HBeAg-negative NA-treated patients, add-on PegIFN therapy achieves higher, albeit modest, HBsAg loss rates compared with continued NA monotherapy and offers the opportunity for NA-treated patients to achieve the inactive carrier state. In the absence of curative therapies, PegIFN represents a valuable, finite option for NA-treated patients who would otherwise require potentially lifelong therapy.

Hepatitis B virus core-related antigen as a surrogate marker for covalently closed circular DNA

BACKGROUND & AIMS

Hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) is a key to viral persistence in chronic hepatitis B infection. Serum hepatitis B core-related antigen (HBcrAg) is a novel marker for HBV disease. We aimed to determine whether HBcrAg could be a surrogate marker for intrahepatic cccDNA.

METHODS

Three hundred and five liver biopsies and the corresponding sera collected from 138 nucleos(t)ide analogues-treated patients were analysed. 124 patients had paired liver biopsies at baseline and 1-year post-treatment, and 43 patients had a third biopsy after 6-12 years of treatment. Serum HBcrAg, HBV DNA and hepatitis B surface antigen (HBsAg), and intrahepatic HBV DNA and cccDNA were measured.

RESULTS

HBcrAg strongly correlated with cccDNA (r=.70), intrahepatic total HBV DNA (r=.67) and serum HBV DNA (r=.69; all P<.0001). In the 130 samples with undetectable serum HBV DNA, HBcrAg was detectable in 101 (78%) samples, and HBcrAg levels still correlated positively with cccDNA (r=.42, P<.0001). At ≥6 years of therapy, the median logarithmic reduction in HBcrAg was 2.7 log kU/mL, which was comparable to the magnitude of reduction in cccDNA. Twenty-one patients had undetectable cccDNA after ≥6 years of treatment, in whom 15 (71%) had detectable HBcrAg (range: 1.2-537 kU/mL).

CONCLUSIONS

Serum HBcrAg is a reliable surrogate marker for intrahepatic cccDNA. HBcrAg could be a very sensitive marker to reflect the cccDNA content and persistence of disease even with the cccDNA levels below the detection limit of assays.

Differences in sequences between HBV-relaxed circular DNA and covalently closed circular DNA

The hepatitis B virus (HBV) genome exists in two forms: circular covalently closed DNA (cccDNA) and relaxed circular DNA (RCDNA). Here, we investigated the presence of differences in the sequences of both forms in paired samples of serum and liver tissue. The serum and liver biopsy samples were collected at the same time from 67 chronically infected patients. The genotyping of the RCDNA and cccDNA was performed using mass spectrometry analysis. The HBV mutations located in the HBV pol (P) and the HBV basal core promoter/pre-core (BCP/PC) regions were included. The BCP/PC and P sequences of the RCDNA extracted from liver and blood samples were different in 39% and 16% of patients, respectively. Differences were also found between RCDNA and cccDNA extracted from the same liver specimen. Moreover, the cccDNA BCP/PC region sequence had an impact on various virological and clinical parameters. We demonstrated that there are differences between the RCDNA and cccDNA sequences that were extracted from the same liver tissue. However, further investigations are needed to analyze whether the mutations in the cccDNA are conserved and whether cccDNA serves as a ‘mutation storage’ pool for HBV. This result could have profound implications for the subsequent therapy choices for treatment-experienced patients.

Pegylated Interferon Alfa-2b Add-on Treatment in Hepatitis B Virus Envelope Antigen-Positive Chronic Hepatitis B Patients Treated with Nucleos(t)ide Analogue: A Randomized, Controlled Trial (PEGON)

Background

We studied whether 48 weeks of pegylated interferon alfa-2b (peginterferon) add-on therapy increases serological response in hepatitis B virus (HBV) envelope antigen (HBeAg)-positive patients receiving nucleos(t)ide analogue (NA) therapy, compared with continued NA monotherapy.

Methods

This randomized trial included HBeAg-positive patients with compensated liver disease who were treated with entecavir/tenofovir for >12 months and had an HBV DNA load of <2000 IU/mL. Patients were randomly assigned in a 1:1 ratio to 48 weeks of peginterferon add-on therapy (n = 39) or continued NA monotherapy (n = 38). Response (defined as HBeAg seroconversion with an HBV DNA load of <200 IU/mL) was assessed at week 48, with responders discontinuing NA therapy at week 72.

Results

The primary end point (response at week 96) was achieved in 18% of patients who were assigned peginterferon add-on therapy versus 8% of patients assigned NA monotherapy (P = .31). Among 58 interferon-naive patients, add-on therapy led to a greater frequency of HBeAg seroconversion (30% vs 7%; P = .034) and response (26% vs 7%; P = .068) at week 96, compared with monotherapy. Among 8 responders at week 48 who discontinued NA therapy at week 72, 6 patients (75%) maintained a response until week 96 (4 of 6 [67%] in the add-on therapy group vs 2 of 2 [100%] in the monotherapy group; P = 1.00). Adverse events were mainly related to peginterferon.

Conclusion

The primary end point was negative, but peginterferon add-on therapy appeared to result in a greater frequency of HBeAg seroconversion, compared with NA monotherapy, in interferon-naive patients receiving NA therapy.

Clinical Trials Registration

NCT01532843.

What is new on HBsAg and other diagnostic markers in HBV infection?

Challenges in the management of chronic hepatitis B virus (HBV) infection involve the prediction of the natural course to identify patients who require antiviral therapy and the prediction of functional cure as ultimate goal of antiviral therapy. HBV DNA as marker for viral replication is important but not sufficient for an adequate management of patients with chronic HBV infection. Data on the quantification of additional HBV marker such as hepatitis B surface antigen (HBsAg), hepatitis B core-related antigen (HBcrAg) and hepatitis B virus RNA (HBV RNA) have accumulated in recent years. Here we review the current evidence how to use these markers and discuss open issues that require additional research.

A Role for the Host DNA Damage Response in Hepatitis B Virus cccDNA Formation-and Beyond?

Chronic hepatitis B virus (HBV) infection puts more than 250 million people at a greatly increased risk to develop end-stage liver disease. Like all hepadnaviruses, HBV replicates via protein-primed reverse transcription of a pregenomic (pg) RNA, yielding an unusually structured, viral polymerase-linked relaxed-circular (RC) DNA as genome in infectious particles. Upon infection, RC-DNA is converted into nuclear covalently closed circular (ccc) DNA. Associating with cellular proteins into an episomal minichromosome, cccDNA acts as template for new viral RNAs, ensuring formation of progeny virions. Hence, cccDNA represents the viral persistence reservoir that is not directly targeted by current anti-HBV therapeutics. Eliminating cccDNA will thus be at the heart of a cure for chronic hepatitis B. The low production of HBV cccDNA in most experimental models and the associated problems in reliable cccDNA quantitation have long hampered a deeper understanding of cccDNA molecular biology. Recent advancements including cccDNA-dependent cell culture systems have begun to identify select host DNA repair enzymes that HBV usurps for RC-DNA to cccDNA conversion. While this list is bound to grow, it may represent just one facet of a broader interaction with the cellular DNA damage response (DDR), a network of pathways that sense and repair aberrant DNA structures and in the process profoundly affect the cell cycle, up to inducing cell death if repair fails. Given the divergent interactions between other viruses and the DDR it will be intriguing to see how HBV copes with this multipronged host system.

Off-Treatment Hepatitis B Virus (HBV) DNA Levels and the Prediction of Relapse After Discontinuation of Nucleos(t)ide Analogue Therapy in Patients With Chronic Hepatitis B: A Prospective Stop Study

Background

The optimal management remains unknown after nucleos(t)ide analogue (NA) discontinuation in patients with chronic hepatitis B (CHB). This prospective study investigated the role of off-treatment viral kinetics in predicting relapse after discontinuation of NA therapy.

Methods

A total of 82 noncirrhotic Asian patients with CHB who discontinued NA therapy according to international guidelines were prospectively followed. Patients with a hepatitis B virus (HBV) DNA level of >2000 IU/mL and an alanine aminotransferase (ALT) level of >2 times the upper limit of normal (clinical relapse) were retreated.

Results

Sixty patients were HBV envelope antigen (HBeAg) positive at the start of treatment, and 22 were HBeAg negative. Clinical relapse developed in 28 patients (2-year rates, 31% among HBeAg-positive patients and 53% among HBeAg-negative patients). Age of ≤35 years (hazard ratio [HR], 0.37; P = .026) and end-of-treatment HBsAg level of ≤200 IU/mL (HR, 0.39; P = .078) were independently associated with lower relapse rates. A high risk of biochemical relapse (defined as an ALT level of >2 times the upper limit of normal) was observed if the HBV DNA level was >200000 IU/mL when the level was initially elevated, compared with HBV DNA levels of >2000 to ≤200000 IU/mL (HR, 8.42; P < .001). The risk of biochemical relapse was also high in patients with persistent elevation in the HBV DNA level (confirmed to be >2000 IU/mL within 3 months), compared with the group with transient elevation (HR, 6.87; P < .001).

Conclusions

After NA discontinuation, a lower relapse rate was observed in younger patients and in those with low end-of-treatment HBsAg levels. The level and persistence of off-treatment elevated HBV DNA levels were useful in the prediction of a subsequent biochemical relapse and may thus be used to guide off-treatment management.