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

Letter: Estimating the incidence of HBsAg seroclearance after cessation of tenofovir and entecavir - potential influence of censored observation

This article is linked to Chen et al papers. To view these articles, visit https://doi.org/10.1111/apt.17602 and https://doi.org/10.1111/apt.17788

Hepatitis B core-related antigen dynamics and risk of subsequent clinical relapses after nucleos(t)ide analog cessation

BACKGROUND/AIMS

Finite nucleos(t)ide analog (NA) therapy has been proposed as an alternative treatment strategy for chronic hepatitis B (CHB), but biomarkers for post-treatment monitoring are limited. We investigated whether measuring hepatitis B core-related antigen (HBcrAg) after NA cessation may stratify the risk of subsequent clinical relapse (CR).

METHODS

This retrospective multicenter analysis enrolled adults with CHB who were prospectively monitored after discontinuing entecavir or tenofovir with negative HBeAg and undetectable HBV DNA at the end of treatment (EOT). Patients with cirrhosis or malignancy were excluded. CR was defined as serum alanine aminotransferase > two times the upper limit of normal with recurrent viremia. We applied time-dependent Cox proportional hazard models to clarify the association between HBcrAg levels and subsequent CR.

RESULTS

The cohort included 203 patients (median age, 49.8 years; 76.8% male; 60.6% entecavir) who had been treated for a median of 36.9 months (interquartile range [IQR], 36.5-40.1). During a median post-treatment follow-up of 31.7 months (IQR, 16.7-67.1), CR occurred in 104 patients with a 5-year cumulative incidence of 54.8% (95% confidence interval [CI], 47.1-62.4%). Time-varying HBcrAg level was a significant risk factor for subsequent CR (adjusted hazard ratio [aHR], 1.53 per log U/mL; 95% CI, 1.12-2.08) with adjustment for EOT HBsAg, EOT anti-HBe, EOT HBcrAg and time-varying HBsAg. During follow-up, HBcrAg <1,000 U/mL predicted a lower risk of CR (aHR, 0.41; 95% CI, 0.21-0.81).

CONCLUSION

Dynamic measurement of HBcrAg after NA cessation is predictive of subsequent CR and may be useful to guide post-treatment monitoring.

Hepatitis B core-related antigen serum levels may be a predictor of acute flare of chronic hepatitis B among pregnant women in the immune-tolerant phase of chronic HBV infection after short-course antiviral therapy

BACKGROUND

Studies have shown acute flares of chronic hepatitis B (CHB) might be related to immunologic changes that occur during pregnancy. However, the indicators for predicting acute flares of CHB among pregnant women still need further study. We aimed to distinguish the relevance between serum levels of HBcrAg and acute flares of CHB in pregnant women in the immune-tolerant phase of chronic HBV infection after short-course antiviral therapy.

METHODS

A total of 172 chronic HBV-infected pregnant women who were judged to be in the immune-tolerant phase were recruited in our research. All patients received short-course antiviral therapy with TDF. The biochemical, serological, and virological parameters were measured using standard laboratory procedures. The serum levels of HBcrAg were tested by ELISA.

RESULTS

Fifty-two (30.2%) out of 172 patients had acute flares of CHB. At postpartum week 12 (TDF cessation), serum HBcrAg (OR, 4.52; 95% CI, 2.58-7.92) and HBsAg (OR, 2.52; 95% CI, 1.13-5.65) were associated with acute flares of CHB. The serum HBcrAg levels were beneficial for confirmation of patients with acute flares of CHB, with an area under the ROC curve of 0.84 (95% CI, 0.78-0.91).

CONCLUSIONS

For pregnant women with chronic HBV infection in the immune-tolerant phase, serum HBcrAg and HBsAg levels at postpartum week 12 were associated with acute flares of CHB after short-course antiviral therapy with TDF. The serum HBcrAg level can correctly identify acute flares of CHB and may be a predictor of the need for continuing antiviral therapy after 12 weeks postpartum.

Hepatitis B core-related antigen: A novel and promising surrogate biomarker to guide anti-hepatitis B virus therapy

The current requirement for biomarkers to detect hepatitis B virus (HBV) infection is polarized. One is a fully-automated and highly sensitive measurement system; the other is a simple system for point-of-care testing (POCT) in resource-limited areas. Hepatitis B core-related antigen (HBcrAg) reflects intrahepatic covalently closed circular DNA and serum HBV DNA. Even in patients with undetectable serum HBV DNA or HBsAg loss, HBcrAg may remain detectable. Decreased HBcrAg levels are associated with reduction of the occurrence of hepatocellular carcinoma (HCC) in chronic hepatitis B. Recently, a fully-automated, novel high-sensitivity HBcrAg assay (iTACT-HBcrAg, cut-off value: 2.1 logIU/mL) has been developed. This attractive assay has been released in Japan very recently. iTACT-HBcrAg can be useful for monitoring HBV reactivation and prediction of HCC occurrence, as an alternative to HBV DNA. Moreover, monitoring HBcrAg may be suitable for determining the therapeutic effectiveness of approved drugs and novel drugs under development. Presently, international guidelines recommend anti-HBV prophylaxis for pregnant women with high viral loads to prevent mother-to-child transmission of HBV. However, >95% of HBV-infected individuals live in countries where HBV DNA quantification is not available. Worldwide elimination of HBV needs the scaling-up of examination and medication services in resource-limited areas. Based on this situation, a rapid and easy HBcrAg assay as a POCT is valuable. This review provides the latest information regarding the clinical use of a new surrogate marker, HBcrAg, in HBV management, based on iTACT-HBcrAg or POCT, and introduces novel agents targeting HBV RNA/protein.

Safety considerations for withdrawal of nucleos(t)ide analogues in patients with chronic hepatitis B: First, do no harm

Nucleos(t)ide analogues (NA) are widely used to treat hepatitis B virus (HBV) infection, but they cannot eradicate the virus and treatment duration can be lifelong if the endpoint is set at seroclearance of the hepatitis B surface antigen (HBsAg). As an alternative strategy, finite NA therapy without the prerequisite of HBsAg seroclearance has been proposed to allow treatment cessation in patients with sustained undetectable HBV viremia for two to three years. However, reactivation of viral replication almost always follows NA withdrawal. Whereas HBV reactivation might facilitate HBsAg seroclearance in some, it could lead to serious acute flare-ups in a certain proportion of patients. Occurrence and consequences of NA withdrawal flares are complicated with various factors involving the virus, host, and treatment. Accurate risk prediction for severe flares following NA cessation is essential to ensure patient safety. The risks of life-threatening flares in patients who discontinued NA according to the stopping rules of current guidelines or local reimbursement policies have recently been quantitatively estimated in large-scale studies, which also provided empirical evidence to help identify vulnerable patients at risk of devastating outcomes. Moreover, risk predictors were further explored and validated to hopefully aid in patient selection and management. In this narrative review with a focus on patient safety, we summarize and discuss current literature on the incidence of severe flares following NA cessation, risk stratification for candidate selection, rules of posttreatment monitoring, and indications for treatment resumption. We also share our thoughts on the limitations of existing knowledge and suggestions for future research.

Letter: Safety after cessation of nucleos(t)ide analogue therapy in patients with chronic hepatitis B infection-Authors' reply

This article is linked to Hsu et al papers. To view these articles, visit https://doi.org/10.1111/apt.17614 and https://doi.org/10.1111/apt.17657

Incidence of Hepatic Decompensation After Nucleos(t)ide Analog Withdrawal: Results From a Large, International, Multiethnic Cohort of Patients With Chronic Hepatitis B (RETRACT-B Study)

INTRODUCTION

Despite improvements in the management of chronic hepatitis B (CHB), risk of cirrhosis and hepatocellular carcinoma remains. While hepatitis B surface antigen loss is the optimal end point, safe discontinuation of nucleos(t)ide analog (NA) therapy is controversial because of the possibility of severe or fatal reactivation flares.

METHODS

This is a multicenter cohort study of virally suppressed, end-of-therapy (EOT) hepatitis B e antigen (HBeAg)-negative CHB patients who stopped NA therapy (n = 1,557). Survival analysis techniques were used to analyze off-therapy rates of hepatic decompensation and differences by patient characteristics. We also examined a subgroup of noncirrhotic patients with consolidation therapy of ≥12 months before cessation (n = 1,289). Hepatic decompensation was considered related to therapy cessation if diagnosed off therapy or within 6 months of starting retreatment.

RESULTS

Among the total cohort (11.8% diagnosed with cirrhosis, 84.2% start-of-therapy HBeAg-negative), 20 developed hepatic decompensation after NA cessation; 10 events were among the subgroup. The cumulative incidence of hepatic decompensation at 60 months off therapy among the total cohort and subgroup was 1.8% and 1.1%, respectively. The hepatic decompensation rate was higher among patients with cirrhosis (hazard ratio [HR] 5.08, P < 0.001) and start-of-therapy HBeAg-positive patients (HR 5.23, P < 0.001). This association between start-of-therapy HBeAg status and hepatic decompensation remained significant even among the subgroup (HR 10.5, P < 0.001).

DISCUSSION

Patients with cirrhosis and start-of-therapy HBeAg-positive patients should be carefully assessed before stopping NAs to prevent hepatic decompensation. Frequent monitoring of viral and host kinetics after cessation is crucial to determine patient outcome.

Editorial: Mitigating the risk of severe hepatitis flare following nucleoside analogue discontinuation-Insights from a real-world study. Authors' reply

This article is linked to Hsu et al papers. To view these articles, visit https://doi.org/10.1111/apt.17614 and https://doi.org/10.1111/apt.17630

Lower pretreatment HBV DNA levels are associated with better off-treatment outcomes after nucleo(s)tide analogue withdrawal in patients with HBeAg-negative chronic hepatitis B: A multicentre cohort study

Background & Aims

Pretreatment predictors of finite nucleo(s)tide analogue (NUC) therapy remain elusive. We studied the association between pretreatment HBV DNA levels and outcomes after therapy cessation.

Methods

Patients with chronic hepatitis B who were HBeAg negative at the start of NUC treatment were enrolled from sites in Asia and Europe. We studied the association between pretreatment HBV DNA levels and (1) clinical relapse (defined as HBV DNA >2,000 IU/ml + alanine aminotransferase >2 × the upper limit of normal or retreatment) and (2) HBsAg loss after NUC withdrawal.

Results

We enrolled 757 patients, 88% Asian, 57% treated with entecavir, with a median duration of treatment of 159 (IQR 156-262) weeks. Mean pretreatment HBV DNA levels were 5.70 (SD 1.5) log IU/ml and were low (<20,000 IU/ml) in 150 (20%) and high (>20,000 IU/ml) in 607 (80%). The cumulative risk of clinical relapse at 144 weeks after therapy cessation was 22% among patients with pretreatment HBV DNA levels <20,000 IU/ml vs. 60% among patients with pretreatment HBV DNA levels >20,000 IU/ml, whereas the cumulative probabilities of HBsAg loss were 17.5% vs. 5% (p <0.001). In multivariable analysis, pretreatment HBV DNA levels <20,000 IU/ml were independently associated with a reduced likelihood of clinical relapse (adjusted hazard ratio 0.379, p <0.001) and with an increased chance of HBsAg loss (adjusted hazard ratio 2.872, p <0.001).

Conclusions

Lower pretreatment HBV DNA levels are associated with a lower risk of clinical relapse and a higher chance of HBsAg loss after cessation of NUC therapy, independent of end-of-treatment viral antigen levels. Further studies are needed to confirm these findings in non-Asian populations.

Impact and Implications

A subgroup of patients with chronic hepatitis B may not require retreatment after stopping antiviral therapy. In this study, comprising 757 patients with chronic hepatitis B from Europe and Asia, we found that higher viral load before initiation of treatment was a risk factor for relapse after stopping treatment. Patients with a low HBV DNA level before starting antiviral therapy had the lowest risk of relapse, and a high chance of HBsAg loss, after stopping treatment. These findings can help select patients for treatment withdrawal and guide intensity of off-treatment monitoring.

Lower end of treatment HBsAg and HBcrAg were associated with HBsAg loss after nucleos(t)ide analog cessation

BACKGROUND

Since hepatitis B surface antigen (HBsAg) loss is rarely achieved with nucleos(t)ide analog (NA) treatment, most patients require life-long NA treatment. Previous studies have shown that some patients remain virologically responsive even after NA cessation. However, there is still controversy surrounding whether NA discontinuation increases the HBsAg loss rate. Therefore, this study aimed to assess the cumulative rate of HBsAg loss and identify the predictors of HBsAg loss after NA discontinuation.

METHODS

This multicenter prospective study included HBV e antigen (HBeAg)-positive patients without cirrhosis from 12 hospitals in China who met the inclusion criteria. The enrolled patients stopped NA and were followed up with clinical and laboratory assessments every 3 months for 24 months after NA cessation or until clinical relapse (CR) occurred.

RESULTS

Overall, 158 patients were classified into two groups. Group A included patients with HBsAg positivity at NA cessation (n = 139), and Group B included patients with HBsAg negativity at NA cessation (n = 19). In Group A, the 12-month and 24-month cumulative rates of HBsAg loss were4.3%and 9.4%, respectively. End of treatment (EOT) HBsAg (hazard ratio (HR) = 0.152, P < 0.001) and EOT hepatitis B core-related antigen (HBcrAg) (HR = 0.257, P = 0.001) were associated with HBsAg loss. The areas under the receiver operating characteristic curves for EOT HBsAg and HBcrAg levels were 0.952 (P < 0.001) and 0.765 (P < 0.001), respectively. Patients with EOT HBsAg ≤ 135 IU/mL (59.2% vs. 1.3%, P < 0.001) or HBcrAg ≤ 3.6 logU/mL (17% vs. 5.4%, P = 0.027) had a higher 24-month cumulative HBsAg loss rate. In Group B, none of the patients experienced virological relapse after NA cessation. Only 1 (5.3%) patient had HBsAg reversion.

CONCLUSIONS

EOT HBsAg ≤ 135 IU/mL or HBcrAg ≤ 3.6 logU/mL can be used to identify patients with a higher likelihood of HBsAg loss after NA cessation. Patients with HBsAg negativity after NA cessation have favorable clinical outcomes, and HBsAg loss was durable in most cases.

Utility of novel viral and immune markers in predicting HBV treatment endpoints: A systematic review of treatment discontinuation studies

Background & Aims

Antivirals represent the mainstay of chronic hepatitis B treatment given their efficacy and tolerability, but rates of functional cure remain low during long-term therapy. Treatment discontinuation has emerged as a strategy to maintain partial cure and achieve functional cure in select patient groups. We aimed to evaluate how data from treatment discontinuation studies exploring novel viral and/or immune markers could be applied to the functional cure program.

Methods

Treatment discontinuation studies evaluating novel viral and/or immune markers were identified by a systematic search of the PubMed database through to October 30, 2022. Data extraction focused on information regarding novel markers, including identified cut-off levels, timing of measurement, and associated effect on study outcomes of virological relapse, clinical relapse, and HBsAg seroclearance.

Results

From a search of 4,492 citations, 33 studies comprising a minimum of 2,986 unique patients met the inclusion criteria. Novel viral markers, HBcrAg and HBV RNA, were demonstrated across most studies to be helpful in predicting off-therapy partial cure, with emerging evidence to support a link with functional cure. From novel immune marker studies, we observed that treatment discontinuation has the potential to trigger immune restoration, which may be associated with a transient virological relapse. To this end, these studies support the combination of virus-directing agents with immunomodulator therapies to induce two key steps underlying functional cure: viral antigen load reduction and restoration of the host immune response.

Conclusions

Patients with a favourable profile of novel viral and immune markers stand to benefit from a trial of antiviral treatment discontinuation alongside novel virus-directing agents with the aim of achieving functional cure without excessive risk of severe clinical relapse.

Impact and implications

Select patients with chronic hepatitis B undergoing nucleoside analogue therapy may benefit from a trial of treatment discontinuation, aiming to maintain partial cure and/or achieve functional cure. We propose a profile of novel viral and immune markers to identify patients who are likely to achieve these goals without excessive risk of hepatic decompensation. Furthermore, treatment discontinuation may also be considered as a therapeutic strategy to trigger immune restoration, which may increase the chance of functional cure when used in conjunction with novel virus-directing agents.

Global burden of hepatitis B virus: current status, missed opportunities and a call for action

Chronic hepatitis B virus (HBV) infection affects about 296 million people worldwide and is the leading aetiology of cirrhosis and liver cancer globally. Major medical complications also include acute flares and extrahepatic manifestations. In addition, people living with HBV infection also experience stigma. HBV-related cirrhosis resulted in an estimated 331,000 deaths in 2019, and it is estimated that the number of deaths from HBV-related liver cancer in 2019 was 192,000, an increase from 156,000 in 2010. Meanwhile, HBV remains severely underdiagnosed and effective measures that can prevent infection and disease progression are underutilized. Birth dose coverage for HBV vaccines remains low, particularly in low-income countries or regions where HBV burden is high. Patients with HBV infection are inadequately evaluated and linked to care and are undertreated worldwide, even in high-income countries or regions. Despite the goal of the World Health Organization to eliminate viral hepatitis as a public health problem by 2030, the annual global deaths from HBV are projected to increase by 39% from 2015 to 2030 if the status quo remains. In this Review, we discuss the current status and future projections of the global burden of HBV infection. We also discuss gaps in the current care cascade and propose future directions.

Combined baseline HBcrAg and end-of-treatment HBsAg predict HBV relapse after entecavir or tenofovir cessation

BACKGROUND

For patients with chronic hepatitis B (CHB), the optimal stopping criteria for entecavir or tenofovir disoproxil fumarate treatment remain unclear.

METHODS

This study recruited CHB patients with levels of hepatitis B surface antigen (HBsAg) <100 IU/mL at the end of treatment (EOT) from Kaohsiung (n = 190) and Linkou (n = 188) Chang Gung Memorial Hospitals for use as development and validation groups, respectively.

RESULTS

In the development group, 108 patients with HBsAg ≤40 IU/mL were used for analysis of predictors of HBV relapse and HBsAg loss. Multivariate analysis showed that age, nucleos(t)ide analogue (NA)-experienced status, baseline hepatitis B core-related antigen (HBcrAg) and HBsAg at EOT were associated independently with virological and clinical relapse. An HBsAg level of 20 IU/mL at EOT was the best cut-off value for minimizing HBV relapse. Patients with EOT HBsAg ≤20 IU/mL had lower virological and clinical relapse rates and higher HBsAg loss rates than those with EOT HBsAg 21-40 IU/mL and HBsAg 41-100 IU/mL in the development and validation groups. The virological and clinical relapse rates were very low (5-year rates: 6.5% and 0%, respectively) and HBsAg loss rate was very high (5-year rate: 81.7%) in patients with a combination of baseline HBcrAg ≤4 log U/mL and EOT HBsAg ≤20 IU/mL in the development group.

CONCLUSIONS

A combination of baseline HBcrAg ≤4 log U/mL and EOT HBsAg level ≤20 IU/mL might reduce the risk of HBV relapse and increase HBsAg loss rate, and might be helpful for off-NA follow-up strategy.

End-of-treatment HBsAg, HBcrAg and HBV RNA predict the risk of off-treatment ALT flares in chronic hepatitis B patients

BACKGROUND/PURPOSE(S)

Since ALT flares after therapy withdrawal are associated with adverse outcomes, risk stratification is of major importance. We aimed to study whether off-treatment flares are related with virological outcomes, and if serum levels of novel biomarkers at end-of-treatment (EOT) can predict flares.

METHODS

Chronic hepatitis B patients who participated in three global randomised trials of peginterferon-based therapy were studied (99-01, PARC, ARES). HBV RNA, HBsAg and HBcrAg were quantified at EOT. Associations between EOT biomarker levels and flares were assessed as continuous data and after categorisation. Flares were defined as ALT ≥5xULN during six months after therapy cessation.

RESULTS

We included 344 patients; 230 HBeAg-positive and 114 HBeAg-negative. Patients were predominantly Caucasian (77.0%) and had genotype A/B/C/D in 23.3/7.3/13.4/52.3%. Flares were observed in 122 patients (35.5%). Flares were associated with lower rates of sustained response (3.5% vs 26.8% among patients with and without a flare; p < 0.001). Higher HBsAg (OR 1.586, 95%CI 1.231-2.043), HBV RNA (OR 1.695, 95%CI 1.371-2.094) and HBcrAg (OR 1.518, 95%CI 1.324-1.740) levels were associated with higher risk of flares (p < 0.001). Combinations of biomarkers further improved risk stratification, especially HBsAg + HBV RNA. Findings were consistent in multivariate analysis adjusted for potential predictors including HBeAg-status and EOT-response (HBV DNA <200 IU/mL).

CONCLUSION

Off-treatment ALT flares were not associated with favourable virological outcomes. Higher EOT serum HBsAg, HBcrAg and HBV RNA were associated with a higher risk of flares after therapy withdrawal. These findings can be used to guide decision-making regarding therapy discontinuation and off-treatment follow-up.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00114361, NCT00146705, NCT00877760.

A Systematic Review on Current Trends in the Treatment of Chronic Hepatitis B to Predict Disease Remission and Relapse

Despite decreasing the prevalence of chronic hepatitis B (CHB), it is still a major health care challenge. Current antiviral regimens aim to suppress hepatitis B virus (HBV) deoxyribonucleic acid (DNA) activity to prevent the risk of hepatic decompensation, liver cirrhosis, and hepatocellular carcinoma (HCC). Currently, pegylated interferon (Peg-IFN) and nucleos(t)ide analogs (NA) are the first-line choices of drugs. Peg-IFN is now discontinued due to its mode of application and side effects. NA is used once daily to suppress HBV DNA activity but has little effect on covalently closed circular DNA (cccDNA), so continuous long-term therapy is required to suppress HBV DNA. Due to this effect, disease remission, relapse, and even clinical flare are common phenomena after the end of treatment (EOT). This review aimed to analyze the current regimens for treating chronic hepatitis B. Their mode of action, duration of treatment, and events after stopping therapy. The review was performed using the preferred reporting items for systematic reviews and meta-analysis (PRISMA) 2020 guidelines. A search was undertaken in PubMed, PubMed Central, Google Scholar, and ScienceDirect. Screening of articles was carried out to find relevant and appropriate articles. Articles were then quality-checked before inclusion. Our analysis showed that long-term finite therapy with nucleoside analogs could improve clinical outcomes and suppress viral DNA activity. However, a functional cure, loss of hepatitis B surface antigen (HBsAg), is rarely achieved. The decision to end treatment depends on quantitative HBsAg level (qHBsAg), alanine aminotransferase (ALT), HBV DNA (deoxyribonucleic acid), hepatitis B e antigen (HBeAg), and fibrosis assessment. It is concluded that patients with HBeAg negative without cirrhosis can be easily withdrawn from treatment if they have long-term viral remission and a high HBsAg loss rate. However, patients with positive HBeAg should continue treatment because there is a high chance of disease relapse and even acute flare. To predict whether patients will benefit from EOT, some immunomodulatory markers are studied, including interleukin (IL-20, IL-8), fas ligand (FASGL), and IFN gamma. Although these factors are reliable, none pose an independent effect on disease remission. Combination therapy (IFN alpha + oral nucleoside analogs) is promising but has clinical shortcomings.

Low anti-HBc levels are associated with lower risk of virological relapse after nucleos(t)ide analogue cessation in HBe antigen-negative patients

BACKGROUND AND AIMS

Low anti-HBc serum levels at the time of therapy cessation were linked to a higher relapse risk in predominantly HBeAg-positive cohorts. We investigated the association of anti-HBc levels with relapse in HBeAg-negative patients.

METHODS

Serum levels of anti-HBc, HBsAg and HBcrAg were determined in 136 HBeAg-negative patients, participating in a vaccination trial (ABX-203, NCT02249988), before treatment cessation or vaccination. Importantly, vaccination showed no impact on relapse. The correlation between the biomarkers and their predictive value for relapse (HBV DNA >2000 IU/ml ± ALT >2xULN) was investigated.

RESULTS

After therapy cessation 50% (N = 68) of patients relapsed. Median anti-HBc prior to treatment stop was significantly higher among relapsers compared to off-treatment responders (520 IU/ml vs. 330 IU/mL, p = .0098). The optimal anti-HBc cut-off to predict relapse was 325 IU/ml according to the Youden-Index. About 35% of patients with anti-HBc level < 325 IU/ml versus 60% of those with values ≥325 IU/mL relapsed (p = .0103; sensitivity 50%, specificity 75%). Combining the optimal cut-offs of HBsAg (>3008 IU/mL) or HBcrAg (≥1790 U/ml) with anti-HBc increased the proportion of patients with relapse to 80% (p < .0001) and 74% (p = .0006), respectively.

CONCLUSION

In contrast to predominantly HBeAg-positive cohorts, in our cohort of HBeAg-negative patients lower anti-HBc levels are associated with a significantly lower relapse risk after nucleos(t)ide analogue cessation. The vast majority of included patients were either genotype B or C and the applicability to other genotypes has to be further evaluated. However, anti-HBc level as an indicator of the host response might be prospectively further explored for prediction models.

Management of hepatitis B virus (HBV) reactivation in patients with resolved HBV infection based on a highly sensitive HB core-related antigen assay

AIMS

To prevent hepatitis B virus (HBV) reactivation-related hepatitis, we examined the clinical usefulness of a highly sensitive HB core-related antigen (iTACT-HBcrAg) assay in patients with resolved HBV infection after nucleos(t)ide analog (NA) treatment for HBV reactivation.

METHODS

We retrospectively analyzed 27 patients with resolved HBV infection who experienced HBV reactivation (defined as HBV DNA levels of 1.3 log IU/ml or more), and who received systemic chemotherapies for hematological malignancies between 2008 and 2020. iTACT-HBcrAg, HBsAg-HQ, and antibodies against hepatitis B surface antigen (anti-HBs) were measured using samples stored after HBV reactivation. The lower limit of quantification for iTACT-HBcrAg was 2.0 log U/ml.

RESULTS

HBV reactivation was diagnosed at a median HBV DNA level of 1.8 log IU/ml, and then all patients received NA treatment. No patient had HBV-related hepatitis with a median maximum HBV DNA level of 2.0 log IU/ml. The positivities of iTACT-HBcrAg and HBsAg-HQ were 96% and 52% after HBV reactivation, respectively. Of 25 patients with detectable iTACT-HBcrAg at the initiation of NA treatment, 17 (68%) achieved iTACT-HBcrAg loss. Median durations from NA treatment to HBV DNA loss and iTACT-HBcrAg loss or the last follow-up were 35 and 175 days, respectively. Recurrence of HBV reactivation after NA cessation was not observed in seven of eight patients who achieved iTACT-HBcrAg loss or seropositive for anti-HBs during follow-up, except for one without anti-HBs after allogeneic transplantation.

CONCLUSIONS

iTACT-HBcrAg could be a potential surrogate marker for diagnosing early-stage HBV reactivation as well as safe cessation of NA treatment in patients with resolved HBV infection after HBV reactivation.

Surrogate Markers for Hepatitis B Virus Covalently Closed Circular DNA

Chronic infection with the hepatitis B virus (HBV) is one of the most common causes of liver disease worldwide. Chronic HBV infection is currently incurable because of the persistence of the viral template for the viral transcripts, covalently closed circular deoxyribonucleic acid (cccDNA). Detecting changes in cccDNA transcriptional activity is key to understanding fundamental virology, determining the efficacy of new therapies, and deciding the optimal clinical management of HBV patients. In this review, we summarize surrogate circulating biomarkers that have been used to infer cccDNA levels and activity in people with chronic hepatitis B. Moreover, we outline the current shortcomings of the current biomarkers and highlight the clinical importance in improving them and expanding their use.

Quantitative anti-HBc combined with quantitative HBsAg can predict HBsAg clearance in sequential combination therapy with PEG-IFN-α in NA-suppressed chronic hepatitis B patients

Background and aims

Precise predictors are lacking for hepatitis B surface antigen (HBsAg) clearance under the combination therapy of nucleos(t)ide analogs (NA) and pegylated interferon-alpha (PEG-IFN-α) in patients with chronic hepatitis B (CHB). This study aimed to determine the quantitative anti-hepatitis B core antibody (qAnti-HBc) and quantitative hepatitis B core-related antigen (qHBcrAg) as predictors for HBsAg clearance in NA-suppressed patients with CHB receiving PEG-IFN-α add-on therapy.

Methods

Seventy-four CHB patients who achieved HBV DNA suppression (HBV DNA &lt; 20 IU/ml) and quantitative HBsAg (qHBsAg) &lt; 1,500 IU/ml after ≥1 year of NA treatment were enrolled. Fifteen patients continued on NA monotherapy, while 59 patients received PEG-IFN-α add-on therapy. Serum qAnti-HBc and qHBcrAg levels were detected every 12 or 24 weeks for add-on and NA-alone groups, respectively.

Results

Serum qAnti-HBc but not qHBcrAg levels at baseline were negatively correlated with the duration of prior NA therapy. After 48-week treatment, both qAnti-HBc and qHBcrAg levels declined further, and 17/59 (28.81%) and 0/15 (0%) achieved HBsAg clearance in add-on and NA groups, respectively. In the add-on group, the rate of HBsAg clearance was significantly higher in patients with baseline qAnti-HBc &lt; 0.1 IU/ml (52.63%). Logistic regression analysis identified baseline qAnti-HBc but not qHBcrAg, which was an independent predictor for HBsAg loss. Receiver operating characteristic curve analysis showed that the combination of qAnti-HBc and qHBsAg had a better predictive value for HBsAg clearance.

Conclusions

A combination of qHBsAg and baseline qAnti-HBc levels may be a better prediction strategy for HBsAg clearance in NA-suppressed CHB patients receiving PEG-IFN-α add-on therapy.

End-of-treatment HBcrAg and HBsAb levels identify durable functional cure after Peg-IFN-based therapy in patients with CHB

BACKGROUND & AIMS

Functional cure can be sustained in a proportion of patients with chronic hepatitis B (CHB) who lose hepatitis B surface antigen (HBsAg) after pegylated interferon alpha (Peg-IFN-ɑ)-based treatment. In this study, we aimed to identify biomarkers associated with a durable functional cure and to dissect potential immunological mechanisms.

METHODS

Of 257 nucleos(t)ide analogue-suppressed patients with CHB in the ANCHOR study, 80 patients randomly assigned to 96-week Peg-IFN-α-based therapy with 24-week off-treatment follow-up were included in this parallel study. Virologic and immunological biomarkers were examined dynamically. A response was defined as HBsAg loss or hepatitis B surface antibody (HBsAb) appearance at the end of treatment (EOT). Sustained response (SR) or durable functional cure was defined as sustained HBsAg loss with or without the appearance of HBsAb at the end of follow-up (EOF).

RESULTS

Thirty-six (45.0%) out of 80 patients achieved a response at EOT; 58.3% (21/36) of responders maintained SR at EOF. Quantitative hepatitis B core-related antigen (qHBcrAg) and HBsAb at EOT were associated with SR, with AUROCs of 0.697 (0.512-0.882, p = 0.047) and 0.744 (0.573-0.915, p = 0.013), respectively. A combination of HBcrAg <4 log₁₀U/ml and HBsAb >2 log₁₀IU/L at EOT had a positive predictive value of 100% for SR with an AUROC of 0.822 (0.684-0.961, p = 0.001). These patients showed maintained proportions of HBV envelope-specific CD8⁺T and B cells, a markedly increased proportion of T follicular helper cells after Peg-IFN-ɑ discontinuation, and significantly higher proportions of HBV polymerase-specific CD8⁺T and CD86⁺CD19⁺B cells at EOF.

CONCLUSIONS

Lower HBcrAg and higher HBsAb levels at EOT were associated with sustained cellular and humoral immune responses. They can be used to identify patients likely to achieve durable functional cure post Peg-IFN-based therapy.

GOV IDENTIFIER

NCT02327416 LAY SUMMARY: Functional cure can be sustained in a proportion of patients with chronic hepatitis B after pegylated interferon alpha-based treatment. However, predicting who will achieve durable functional cure remains challenging. Herein, we show that low levels of hepatitis B core-related antigen and higher levels of hepatitis B surface antibodies at the end of treatment are linked to immunological responses and are associated with durable functional cure.

Virological Treatment Monitoring for Chronic Hepatitis B

More than 250 million people worldwide are currently infected with hepatitis B, despite the effectiveness of vaccination and other preventive measures. In terms of treatment, new therapeutic approaches are rapidly developing, promising to achieve the elimination of infected cells and the complete cure of infection. The on-treatment monitoring of these innovative antiviral treatments will require the implementation of new virological tools. Therefore, new biomarkers are being evaluated besides the traditional virological and serological assays in order to obtain information on different steps of the viral replication cycle and to monitor response to therapy more accurately. The purpose of this work is to describe both standard and innovative tools for chronic hepatitis B treatment monitoring, and to analyse their potential and feasibility.

Serum Pregenomic RNA Combined With Hepatitis B Core-Related Antigen Helps Predict the Risk of Virological Relapse After Discontinuation of Nucleos(t)ide Analogs in Patients With Chronic Hepatitis B

Background and Aim

Cessation of nucleos(t)ide analogs (NAs) therapy in patients with chronic hepatitis B (CHB) is uncommon. Although criteria for discontinuation appear in some guidelines, the indicators for assessing discontinuation of NAs are limited, whether NAs can be safely ceased remains a difficult clinical issue. Our study aimed to investigate the role of serum pregenomic RNA (pgRNA) and hepatitis B core-related antigen (HBcrAg) at the end of treatment (EOT) in guiding the safe discontinuation of NAs in CHB patients.

Methods

This is a retrospective study, clinical data of all CHB patients who discontinued NAs treatment at West China Hospital between June 2020 and January 2021 were collected, including EOT pgRNA, HBcrAg, hepatitis B surface antigen (HBsAg), etc. All patients should meet the Asian-Pacific guideline for discontinuation. Observing virological relapse (VR) rates during 1 year of NAs discontinuation and analyzing the relationship between EOT pgRNA, HBcrAg, and VR.

Results

A total of 64 patients were enrolled in this study and 33 (51.5%) patients experienced VR in 1 year. EOT pgRNA positivity (OR = 14.59, p = 0.026) and EOT higher HBcrAg levels (OR = 14.14, p = 0.001) were independent risk factors for VR. The area under the receiver-operating characteristic (AUROC) value of EOT HBcrAg for VR was 0.817 (p < 0.001), optimal cut-off value was 3.3 log10 U/mL. Patients with EOT pgRNA positivity and EOT HBcrAg >3.3 log10 U/mL were more likely to experience VR after discontinuation of NAs (88.9 vs. 45.5%, p = 0.027).

Conclusion

According to current guidelines, a higher VR rate occurs after cessation of NAs. EOT pgRNA positivity and higher HBcrAg level carries a higher risk of VR. Combining these novel markers can better help us assess whether patients can safely cease NAs treatment.

Severe Acute Exacerbation After Cessation of Nucleos(t)ide Analog for Chronic Hepatitis B: A Real-World Study of Routine Practice

There is an ongoing debate as to whether patients with chronic hepatitis B (CHB) may discontinue nucleos(t)ide analogue (NA) therapy before seroclearance of hepatitis B surface antigen (HBsAg).1 Whereas treatment discontinuation may facilitate HBsAg seroclearance and avoid indefinite drug exposure,2 reactivation of viral replication almost always follows treatment cessation and frequently leads to clinical flares.3 In patients who encounter withdrawal flares, severe acute exacerbation (SAE) could occur with fatal consequences.4 Quantitative knowledge about the risk of SAE is imperative to inform the debate and also the practice.

Probability of HBsAg loss after nucleo(s)tide analogue withdrawal depends on HBV genotype and viral antigen levels

BACKGROUND & AIMS

Nucleo(s)tide analogue (NUC) withdrawal may result in HBsAg clearance in a subset of patients. However, predictors of HBsAg loss after NUC withdrawal remain ill-defined.

METHODS

We studied predictors of HBsAg loss in a global cohort of HBeAg-negative patients with undetectable HBV DNA who discontinued long-term NUC therapy. Patients requiring retreatment after treatment cessation were considered non-responders.

RESULTS

We enrolled 1,216 patients (991 with genotype data); 98 (8.1%) achieved HBsAg loss. The probability of HBsAg loss was higher in non-Asian patients (adjusted hazard ratio [aHR] 8.26, p <0.001), and in patients with lower HBsAg (aHR 0.243, p <0.001) and HBV core-related antigen (HBcrAg) (aHR 0.718, p = 0.001) levels. Combining HBsAg (<10, 10-100 or >100 IU/ml) and HBcrAg (<2log vs. ≥2 log) levels improved prediction of HBsAg loss, with extremely low rates observed in patients with HBsAg >100 IU/ml with detectable HBcrAg. HBsAg loss rates also varied with HBV genotype; the highest rates were observed for genotypes A and D, and none of the patients with HBV genotype E experienced HBsAg loss (p <0.001 for the overall comparison across genotypes; p <0.001 for genotypes A/D vs. genotypes B/C). HBV genotype C was independently associated with a higher probability of HBsAg loss when compared to genotype B among Asian patients (aHR 2.494; 95% CI 1.490-4.174, p = 0.001).

CONCLUSIONS

The probability of HBsAg loss after NUC cessation varies according to patient ethnicity, HBV genotype and end-of-treatment viral antigen levels. Patients with low HBsAg (<100 IU/ml) and/or undetectable HBcrAg levels, particularly if non-Asian or infected with HBV genotype C, appear to be the best candidates for treatment withdrawal.

LAY SUMMARY

A subset of patients may achieve clearance of hepatitis B surface antigen (HBsAg) - so-called functional cure - after withdrawal of nucleo(s)tide analogue therapy. In this multicentre study of 1,216 patients who discontinued antiviral therapy, we identified non-Asian ethnicity, HBV genotype C, and low hepatitis B surface antigen and hepatitis B core-related antigen levels as factors associated with an increased chance of HBsAg loss.

Prediction of Sustained Response After Nucleo(s)tide Analogue Cessation Using HBsAg and HBcrAg Levels: A Multicenter Study (CREATE)

BACKGROUND & AIMS

Predictors of successful nucleo(s)tide analogue (NA) therapy withdrawal remain elusive. We studied the relationship between end-of-treatment levels of hepatitis B core-related antigen (HBcrAg) and hepatitis B surface antigen (HBsAg) and outcome after therapy cessation.

METHODS

Patients who discontinued NA therapy in centers in Asia and Europe were enrolled. HBcrAg and HBsAg were measured at treatment cessation, and associations with off-treatment outcomes were explored. The SCALE-B (Surface antigen, Core-related antigen, Age, ALT, and tenofovir for HBV) score was calculated as previously reported. End points included sustained virologic response (VR; hepatitis B virus DNA level <2000 IU/mL), HBsAg loss, and alanine aminotransferase (ALT) flares (>3× upper limit of normal). Re-treated patients were considered nonresponders.

RESULTS

We analyzed 572 patients, 457 (80%) were Asian and 95 (17%) were hepatitis B e antigen positive at the start of NA therapy. The median treatment duration was 295 weeks. VR was observed in 267 (47%), HBsAg loss was observed in 24 (4.2%), and ALT flare was observed in 92 (16%). VR (67% vs 42%) and HBsAg loss (15% vs 1.5%) was observed more frequently in non-Asian patients when compared to Asian patients (P < .001). Lower HBcrAg levels were associated with higher rates of VR (odds ratio [OR], 0.701; P < .001) and HBsAg loss (OR, 0.476; P < .001), and lower rates of ALT flares (OR, 1.288; P = .005). Similar results were observed with HBsAg (VR: OR, 0.812; P = .011; HBsAg loss: OR, 0.380; P < .001; and ALT flare: OR, 1.833; P < .001). Lower SCALE-B scores were associated with higher rates of VR, HBsAg loss, and lower rates of ALT flares in both Asian and non-Asian patients (P < .001).

CONCLUSIONS

In this multicenter study, off-treatment outcomes after NA cessation varied with ethnicity. Lower levels of HBcrAg and HBsAg were associated with favorable outcomes. A risk score comprising both factors can be used for risk stratification.

Biomarkers for predicting nucleos(t)ide analogs discontinuation and hepatitis B virus recurrence after drug withdrawal in chronic hepatitis B patients

AIM

To summarize HBV-related biomarkers predicting nucleos(t)ide analogs (NAs) discontinuation and hepatitis B virus (HBV) recurrence after drug withdrawal in chronic hepatitis B (CHB) patients, providing references for clinical medication, so as to manage CHB patients more scientifically.

METHODS

Related pieces of literature were retrieved in PubMed and the results were sorted out. We then analyzed and summarized these articles.

RESULTS

We found that HBV related biomarkers maybe could predict NAs withdrawal safely and the possibility of relapse after treatment cessation, including hepatitis B e antigen (HBeAg), hepatitis B surface antigen (HBsAg), HBV DNA, HBV RNA, pregenomic-RNA (pgRNA), hepatitis B core-related antigen (HBcrAg), hepatitis B core antibody (anti-HBc), and models containing several indicators for predicting the effectiveness of treatment.

CONCLUSIONS

HBV DNA, HBV RNA, pgRNA, HBcrAg, anti-HBc, as well as the prediction models formed by several biomarkers could predict the safe discontinuation of NAs before HBsAg loss and recurrence.

HBcrAg Levels Are Associated With Virological Response to Treatment With Interferon in Patients With Hepatitis Delta

Standard treatment of hepatitis delta virus (HDV) infection remains pegylated-interferon alfa (peg-IFNα) in most centers, which is not only associated with rather low efficacy but several adverse events. Hepatitis B core-related antigen (HBcrAg) is linked to intrahepatic covalently closed circular DNA levels and has previously been suggested as response predictor in IFN-based treatment of hepatitis B virus (HBV) mono-infection. This study aimed to investigate the value of HBcrAg in the management of patients with HBV/HDV co-infection undergoing peg-IFNα treatment. The Hep-Net-International-Delta-Hepatitis-Intervention Trial-2 study included 120 patients co-infected with HBV/HDV. Patients were treated for 96 weeks with peg-IFNα and either tenofovir or placebo. Ninety-nine patients with HDV-RNA results 24 weeks after end of treatment (FU24) were included in this analysis, of whom 32 patients (32.3%) had undetectable HDV RNA at FU24. HBcrAg was measured at baseline, week 12, 24, 48, 96, and FU24. HBcrAg levels showed no significant correlation with HDV RNA but were significantly linked to treatment outcome. HBcrAg levels < 4.5 log IU/mL at baseline, week 24, and week 48 had high negative predictive value (NPV) for achieving undetectable HDV RNA at FU24 (81.8%, 87.1% and 95.0%, respectively). Similarly, HBcrAg levels at week 96 were significantly higher in patients with viral relapse until FU24 (3.0 vs. 3.63 log IU/mL; P = 0.0089). Baseline, week 24, and week 48 HBcrAg levels were also associated with the likelihood of achieving HBsAg level < 100 IU/mL at FU24 (HBcrAg < 3.0 log IU/mL: NPV 91.7%, 90.4% and 92.3%, respectively). Test statistics improved when combining HBcrAg with additional viral and clinical parameters. Conclusion: HBcrAg is linked to treatment response to peg-IFNα in patients with HBV/HDV co-infection and could be a promising marker to determine treatment futility.

Clinical Utility of SCALE-B to Predict Hepatitis B Virus Relapse, Hepatitis B Surface Antigen Loss After Antiviral Cessation in Asian Patients After 2-Year Follow-up

BACKGROUND

Discontinuation of antiviral therapy in chronic hepatitis B (CHB) patients leads to a higher hepatitis B surface antigen (HBsAg) loss; yet, clinical relapse (CR) may occur. SCALE-B score was developed to predict off-treatment CR; however, validation of SCALE-B beyond a 48-week follow-up is rare. We studied whether SCALE-B and hepatitis B virus ribonucleic acid (HBV RNA) could predict outcomes in CHB patients after a 2-year follow-up.

METHODS

A total of 92 Thai CHB patients who stopped antiviral treatment were followed up; baseline characteristics, quantitative hepatitis B surface antigen (qHBsAg), hepatitis B core-related antigen (HBcrAg), and HBV RNA were collected at the time of discontinuation, and SCALE-B scores were calculated. Patients were followed up every 12 weeks for 48 weeks, and then, the intervals were upon primary doctors. Follow-up data regarding virological relapse (VR), CR, and HBsAg loss were obtained.

RESULTS

The median follow-up duration was 142 weeks; the cumulative incidences of VR, CR, and HBsAg loss were 65.2, 33.7, and 7.6%, respectively. After 48 weeks, VR and CR plateaued, but HBsAg loss increased from 2.2 to 7.6%. According to the SCALE-B strata, VR, CR, and HBsAg loss were significantly different. The highest stratum (≥ 320) was associated with higher VR, CR, and lesser HBsAg loss when compared to the lowest stratum, with adjusted hazard ratios of 5.0 (95% CIs: 1.8-14.4), 10.44 (95% CIs: 1.4-79.1), and 0.04 (95% CIs: 0.004-0.43), respectively.

CONCLUSION

At a median follow-up of 2.5 years after discontinuing therapy, HBsAg loss in Thai patients was found to increase over time. SCALE-B is a valuable tool for predicting CR, VR, and HBsAg loss; HBV RNA is not significantly associated with long-term outcomes.

CLINICAL TRIAL REGISTRATION

[www.ClinicalTrials.gov], identifier [TCTR20180316007].

Insufficient immunity led to virologic breakthrough in NAs-treated chronic hepatitis B patients switching to Peg-IFN-ɑ

BACKGROUND

Virologic breakthrough (VBT) may occur in chronic hepatitis B (CHB) patients after switching from nucleos(t)ide analogues (NAs) to pegylated interferon alpha (Peg-IFN-ɑ). This study aimed to characterize the clinical and immunological features of VBT.

METHODS

In NAs-treated patients switching to Peg-IFN-ɑ, innate and adaptive immune cell proportions were examined in peripheral blood and liver biopsy specimens. In vitro effect of IFN-ɑ on the expressions of toll-like receptors 2 (TLR2) and programmed cell death ligand 1 (PDL1) on monocytes, programmed cell death 1 (PD1) on CD8⁺T cells was examined. Peripheral blood mononuclear cells (PBMCs) were treated with TLR2 agonist and/or PDL1 blockade to evaluate their effect on HBV replication.

RESULTS

33 of 166 patients switching to Peg-IFN-ɑ experienced VBT after NA cessation, with majority being hepatitis B e antigen (HBeAg) positive or having higher hepatitis B core-related antigen (HBcrAg) levels. Patients with VBT exhibited lower proportions of TLR2⁺monocyte and increased PD1⁺HBV-specific CD8⁺T cell during the early phase of Peg-IFN-ɑ therapy after NA cessation in peripheral blood, as well as fewer TLR2⁺CD68⁺macrophages but more PDL1⁺CD68⁺macrophages and PD1⁺CD8⁺T cells in liver tissues. Simultaneous use of TLR2 agonist and PDL1 blockage ex vivo suppressed HBV replication by promoting cytokines production and CD8⁺T cells cytotoxicity. Upon in vitro IFN-ɑ stimulation, PDL1⁺monocytes and PD1⁺CD8⁺T cells were upregulated, whereas TLR2⁺monocytes were not increased in PBMC isolated from HBeAg-positive patients, or those with high HBcrAg titers.

CONCLUSIONS

In NAs-treated patients, lower TLR2⁺monocyte and increased PD1⁺HBV-specific CD8⁺T cell proportions potentially contribute to VBT after switching to Peg-IFN-ɑ therapy. This insufficient immunity may be associated with the HBeAg status and HBcrAg levels.

Hepatitis B Core-Related Antigen and New Therapies for Hepatitis B

The hepatitis B core-related antigen (HBcrAg) is an unprecedented novel HBV biomarker that plays an essential role in reflecting covalently closed circular DNA (cccDNA) in chronic hepatitis B (CHB) because its levels correlate with intrahepatic cccDNA and serum HBV DNA. In this review, we describe the clinical application of serum HBcrAg in CHB patients, with a particular focus on new therapies targeting intrahepatic HBV replication. (1) HBcrAg can be detected in clinical cases where serum HBV DNA is undetectable during anti-HBV therapy. (2) A highly sensitive HBcrAg assay (iTACT-HBcrAg) may be useful for monitoring HBV reactivation, as an alternative to HBV DNA. (3) Decreased HBcrAg levels have been significantly associated with promising outcomes in CHB patients, reducing the risk of progression or recurrence of hepatocellular carcinoma. Additionally, we focus on and discuss several drugs in development that target HBV replication, and monitoring HBcrAg may be useful for determining the therapeutic efficacies of such novel drugs. In conclusion, HBcrAg, especially when measured by the recently developed iTACT-HBcrAg assay, may be the most appropriate surrogate marker, over other HBV biomarkers, to predict disease progression and treatment response in CHB patients.

Risks and Benefits of Discontinuation of Nucleos(t)ide Analogue Treatment: A Treatment Concept for Patients With HBeAg-Negative Chronic Hepatitis B

Systematic discontinuation of long-term treatment with nucleos(t)ide analogues (NAs) is one strategy to increase functional cure rates in patients with chronic hepatitis B e antigen (HBeAg)-negative hepatitis B. Currently, available study results are heterogeneous; however, long-term hepatitis B surface antigen (HBsAg) loss rates of up to 20% have been reported in prospective trials. This review proposes criteria that can be used when considering NA discontinuation in patients with chronic hepatitis B virus (HBV). Discontinuing NA treatment frequently results in a virologic and biochemical relapse that runs through different phases: the lag phase, reactivation phase, and consolidation phase. The HBV-DNA flares observed during the reactivation phase are often transient and most likely represent a trigger for inducing a long-term immune control by specific CD8+ T cells, and therefore do not need immediate interventions but close follow-up evaluation. Low HBsAg levels at the time of treatment cessation predict a positive long-term response to NA discontinuation associated with a higher likelihood of HBsAg clearance. Other host and viral biomarkers are currently under evaluation that may prove to be helpful to further characterize the population that may benefit most from the finite NA treatment concept. Potential harmful biochemical flares during the reactivation phase need to be identified early and can be effectively terminated by reintroducing NA treatment. Hepatic decompensation represents a risk to patients with cirrhosis undergoing NA discontinuation. Therefore, the finite NA approach should only be considered after excluding advanced fibrosis and cirrhosis and if a close follow-up of the patient and supervision by an experienced physician can be guaranteed. Conclusion: For selected patients, NA discontinuation has become a powerful tool to achieve control over HBeAg-negative HBV infections. Its significant effect represents a challenge to novel treatment approaches, but it may also serve as their enhancer.

Challenges in the discontinuation of chronic hepatitis B antiviral agents

Long-term antiviral treatment of chronic hepatitis B patients has been proven to be beneficial in reducing liver-related complications. However, lengthy periods of daily administration of medication have some inevitable drawbacks, including decreased medication adherence, increased cost of treatment, and possible long-term side effects. Currently, discontinuation of antiviral agent has become the strategy of interest to many hepatologists, as it might alleviate the aforementioned drawbacks and increase the probability of achieving functional cure. This review focuses on the current evidence of the outcomes following stopping antiviral treatment and the factors associated with subsequent hepatitis B virus relapse, hepatitis B surface antigen clearance, and unmet needs.

Hepatitis B Core-Related Antigen is a Biomarker for off-Treatment Relapse After Long-Term Nucleos(t)ide Analog Therapy in Patients with Chronic Hepatitis B

Objective

It remains unknown how to stratify the risk of clinical relapse of chronic hepatitis B (CHB) patients after stopping nucleos(t)ide analogs (NAs) antiviral therapy.

Methods

The current post hoc analysis included 122 non-cirrhotic patients with chronic hepatitis B virus infection who were positive for hepatitis B envelope antigen (HBeAg) and discontinued long-term NA therapy after achieving HBeAg seroconversion for a median of 2.5 years. Post hoc analysis of end-of-treatment (EOT) hepatitis B core-related antigen (HBcrAg) levels was performed using a chemiluminescent enzyme immunoassay.

Results

A total of 78/122 (63.9%) patients experienced sustained response after NAs cessation, and 44/122 (36.1%) patients experienced clinical relapse. In multivariate analysis, EOT HBcrAg (hazard ratio [HR] = 2.105 95% CI: 1.440–3.077, p < 0.001), hepatitis B surface antigen (HBsAg) ≥100 IU/mL (HR = 4.406, 95% CI 1.567–12.389, p = 0.005) and age (HR = 1.051, 95% CI: 1.010–1.093, p = 0.049) were independently associated with clinical relapse. A cut-off value of 4.0 log₁₀ U/mL of HBcrAg was defined by maximized Youden’s index. An EOT HBcrAg level of ≥4.0 log₁₀ U/mL was associated with higher risks of clinical relapse (65.8% vs 23.2%, p<0.001) and HBeAg reversion (27.5% vs 1.6%, p < 0.001). In majority of patients (n = 91) who had a high EOT HBsAg level (≥100 IU/mL), serum HBcrAg level could further discriminate patients at low risk of clinical relapse. Patients with an HBcrAg level ≥4.0 log₁₀ U/mL had significantly higher cumulative incidence rates of clinical relapse (78.1% vs 29.4%, p < 0.001) and HBeAg reversion (29.4% vs 0%, p < 0.001).

Conclusion

Serum EOT HBcrAg level can be a predictor of off-treatment relapse in patients with CHB. An HBcrAg level of 4.0 log₁₀ U/mL may identify patients at high risk of clinical relapse after treatment cessation.

Novel viral markers and the prediction of off-treatment relapse in chronic hepatitis B patients: A systematic review

BACKGROUND AND AIM

Hepatitis B core-related antigen (HBcrAg) and hepatitis B virus RNA (HBV RNA) are novel markers that reflect intrahepatic cccDNA and could be useful in the prediction of relapse after nucleos(t)ide analogues (NA) discontinuation. The aim of the study is to perform a systematic review on this issue.

METHODS

Medline/Pubmed database was searched using text terms related to HBcrAg, RNA, NAs, discontinuation, and relapse. Included studies were those that enrolled adult patients who had been on NAs for more than 6 months with available information on end-of-treatment (EOT) HBcrAg and/or HBV RNA and relapse rates.

RESULTS

Sixteen studies were included. Virological and clinical relapse rates ranged from 11% to 100% and 11% to 73%, respectively. Low or undetectable EOT HBcrAg levels were associated with low off-treatment relapse rates in most studies with area under the receiver operating characteristic curve (AUROC) of 0.69-0.70 for predicting virological relapse (VR) and 0.61-0.77 for predicting clinical relapse (CR). Undetectable EOT HBV RNA was associated with a lower risk of off-treatment relapse with AUROC of 0.65-0.76 for predicting VR and 0.66-0.73 for predicting CR. Combined EOT HBcrAg and HBV RNA performed better in predicting off-treatment relapse than either test alone with AUROC of 0.816-0.846 for predicting CR. None of the patients with double-negative HBV RNA and HBcrAg developed CR.

CONCLUSION

Combining HBcrAg with HBV RNA or HBsAg improved the discriminating abilities in the prediction of off-treatment relapse of each test. Patients with double-negative HBcrAg and HBV RNA at EOT had low risks of relapse and could be considered for NA discontinuation.

The times they are a-changing - A refined proposal for finite HBV nucleos(t)ide analogue therapy

Although discontinuation of nucleos(t)ide analogue (NA) treatment before HBsAg loss is part of all current HBV treatment guidelines for HBeAg-positive patients who achieve HBeAg seroconversion, a treatment endpoint known to be associated with silencing of HBV transcriptional activity and restoration of HBV-specific immune control, whether it is even appropriate to consider NA discontinuation before HBsAg loss in the HBeAg-negative phase remains highly controversial. Despite the growing evidence that a relevant, albeit small, proportion of patients with HBeAg-negative disease can be cured by stopping NA treatment, the fear of discontinuation-associated relapse and the uncertainty of how to predict off-therapy response and monitor patients after discontinuation have generated scepticism and subsequently led to low implementation of this concept in the clinic. In this article, we propose a concept in which NA discontinuation-associated relapse is an integral part of the stop-to-cure approach and ultimately the trigger for achieving HBsAg loss. However, the relapse in this sense becomes functionally effective only if HBV-specific immune reinvigoration and silencing of HBV transcriptional activity have been achieved during the NA treatment period. The probability of functional cure and the severity of post-discontinuation flares depend on the underlying baseline transcriptional activity of HBV when NA therapy was started, as well as the duration of NA treatment, both factors that should be considered as we move towards individualised approaches to HBV cure.

The role of hepatitis B virus core-related antigen in predicting hepatitis B virus relapse after cessation of entecavir in hepatitis B e antigen-negative patients

This study investigated the ability of hepatitis B core-related antigen (HBcrAg) to predict hepatitis B virus (HBV) relapse in HBeAg-negative patients after cessation of entecavir therapy. A total of 301 HBeAg-negative patients without cirrhosis who had stopped entecavir therapy for at least 12 months were recruited. All patients fulfilled the stopping criteria proposed by the APASL 2012 guidelines. The five-year cumulative rates of virological relapse, clinical relapse and HBsAg loss were 71.6%, 57.3% and 18.7%, respectively. Serum HBsAg at end of treatment (EOT) was an independent predictor of virological relapse, clinical relapse and HBsAg loss; an EOT HBsAg of 150 IU/ml was the optimal cut-off value. The 5-year virological relapse rates for patients with <150 and ≥150 IU/ml HBsAg at EOT were 43.3% and 82.2% (p < 0.001), clinical relapse rates were 32.3% and 66.3% (p < 0.001), and HBsAg loss rates were 46.1% and 5.2% (p < 0.001), respectively. A baseline HBcrAg of 4 IU/ml was the optimal cut-off value for predicting HBV relapse. Among patients with an EOT HBsAg <150 IU/ml, the five-year virological relapse rates for patients with baseline HBcrAg levels ≤4 and >4 log U/ml were 27.9% and 59.1% (p = 0.006) and the clinical relapse rates were 18% and 48.1% (p = 0.014), respectively. EOT HBcrAg was not a significant predictor of virological or clinical relapse after cessation of entecavir. In conclusion, the combination of an EOT HBsAg of 150 IU/ml and baseline HBcrAg of 4 log U/ml can effectively predict the risk of HBV relapse after stopping entecavir therapy.

APASL guidance on stopping nucleos(t)ide analogues in chronic hepatitis B patients

Chronic hepatitis B virus (HBV) infection is currently incurable. Long-term treatment with potent and safe nucleos(t)ide analogs (NAs) can reduce hepatocellular carcinoma (HCC) and cirrhosis-related complications through profound viral suppression. However, indefinite therapy raises several crucial issues with pros and cons. Because seroclearance of hepatitis B surface (HBsAg) as functional cure is not easily achievable, a finite therapy including sequential 48-week pegylated interferon therapy may provide an opportunity to facilitate HBsAg seroclearance by the rejuvenation of exhausted immune cells. However, the cost of stopping NA is the high incidence of virological relapse and surge of alanine aminotransferase (ALT) levels, which may increase the risk of adverse outcomes (e.g., decompensation, fibrosis progression, HCC, or liver-related mortality). So far, the APASL criteria to stop NA treatment is undetectable HBV DNA levels with normalization of ALT; however, this criterion for cessation of treatment is associated with various incidence rates of virological/clinical relapse and more than 40% of NA-stoppers eventually receive retreatment. A very intensive follow-up strategy and identification of low-risk patients for virological/clinical relapse by different biomarkers are the keys to stop the NA treatment safely. Recent studies suggested that decreasing HBsAg level at the end-of-treatment to < 100-200 IU/mL seems to be a useful marker for deciding when to discontinue NAs therapy. In addition, several viral and host factors have been reviewed for their potential roles in predicting clinical relapse. Finally, the APASL guidance has proposed rules to stop NA and the subsequent follow-up strategy to achieve a better prognosis after stopping NA. In general, for both HBeAg-positive and HBeAg-negative patients who have stopped treatment, these measurements should be done every 1-3 months at the minimum until 12 months.

Nucleoside/nucleotide analog consolidation therapy in hepatitis B e-antigen positive chronic hepatitis B patients: Three years should be preferred

AIM

To assess the role of consolidation therapy after cessation of nucleoside/nucleotide analogs (NAs) for off-treatment outcome and to explore the optimal consolidation period in hepatitis B e-antigen (HBeAg) positive chronic hepatitis B (CHB) patients.

METHODS

We undertook a prospective, observational cohort study including HBeAg positive CHB patients discontinuing NAs. Virological relapse was the primary endpoint of the current study and was defined as a serum hepatitis B virus DNA more than 10⁴ copies/ml (another assay was carried out for confirmation at least 2 weeks later). Propensity score matching analysis was used to balance the baseline characteristics between HBeAg positive CHB patients with different consolidation periods.

RESULTS

A total of 190 HBeAg positive CHB patients were included. Fifty-four patients relapsed during follow-up and the cumulative relapse rates at years 1, 3, 5, and 10 were 19.5%, 24.1%, 27.2%, and 32.1%, respectively. Most patients (61.1%) relapsed in the first 6 months. After propensity score matching, significantly lower cumulative relapse rates were observed in patients with consolidation period ≥36 months compared with patients with consolidation period more than 36 months (29.3% vs. 52.8% at year 10; p = 0.012).

CONCLUSIONS

Cessation of NAs after HBeAg seroconversion and long-term consolidation is generally safe and feasible in HBeAg positive CHB patients. Three years of consolidation should be preferred in clinical practice.

Clinical Implications of Serum Hepatitis B Virus Pregenomic RNA Kinetics in Chronic Hepatitis B Patients Receiving Antiviral Treatment and Those Achieving HBsAg Loss

Serum hepatitis B virus (HBV) pregenomic RNA (pgRNA) is correlated with covalently closed circular DNA. We aimed to investigate the utility of serum HBV pgRNA in chronic hepatitis B patients receiving nucleos(t)ide analogue treatment and those achieving HBsAg loss. One hundred and eighty-five patients were enrolled for studying long-term HBV pgRNA kinetics during treatment. Twenty patients achieving HBsAg loss after treatment were enrolled for examining HBV pgRNA kinetics around HBsAg loss. HBV pgRNA significantly decreased in the high baseline HBV pgRNA (≥6 log copies/mL) group but significantly increased in the low baseline HBV pgRNA (<4 log copies/mL) group after 3-month entecavir treatment. Among the 20 patients achieving HBsAg loss, 13 (65%) patients had serum HBV pgRNA higher than the limit of detection (LOD, 1466 copies/mL) when they achieved HBsAg loss. Finally, all 20 patients had HBV pgRNA going below the LOD within 3 years after achieving HBsAg loss. In conclusion, baseline serum HBV pgRNA alone is insufficient for predicting the trajectory of HBV pgRNA. Most patients still had HBV pgRNA higher than the LOD when they achieved HBsAg loss. Further studies on HBV pgRNA kinetics around HBsAg loss would provide an enhanced basis for further applications of HBV pgRNA.

Hepatitis B Core-Related Antigen: From Virology to Clinical Application

Hepatitis B core-related antigen (HBcrAg) is a composite measure of the serum levels of hepatitis B e antigen, hepatitis B core antigen, and a 22-kDa precore protein. It has been shown to reflect the level and transcriptional activity of covalently closed circular DNA in the liver. Longitudinal cohort studies have improved our understanding of the role of this novel viral marker in the natural history of chronic hepatitis B. HBcrAg kinetics reflect the response to peginterferon, and its role in defining guidelines for stopping peginterferon therapy has been evaluated. HBcrAg is a marker of intrahepatic viral activity, which may influence the risk of hepatocellular carcinoma. In this article, we review the virology and role of HBcrAg in defining phases of chronic hepatitis B. Furthermore, the function of HBcrAg in predicting treatment outcomes and its role in monitoring response to novel antiviral agents will be discussed.

Combined viral quasispecies diversity and hepatitis B core-related antigen predict off-nucleos(t)ide analog durability in HBeAg-negative patients

BACKGROUND

Viral quasispecies dynamics between pre- and post-nucleos(t)ide analog (NA) therapy remains unclear.

AIM

This study aimed to investigate the HBV quasispecies evolution and its relationship with durability of off-therapy responses in HBeAg-negative chronic hepatitis B (CHB) patients who stopped NA therapy.

METHODS

Fifty-four HBeAg-negative CHB patients who stopped NAs, including 19 virological controllers (VC) who maintained serum HBV DNA < 2000 IU/mL beyond 1-year off-therapy, and 35 virological relapsers (VR) experiencing virological relapse within 1-year off-therapy were recruited. Viral quasispecies was analyzed by deep sequencing. Hepatitis B core-related antigen (HBcrAg) and HBsAg were also measured.

RESULTS

VC had significantly higher baseline viral quasispecies diversity of the precore/core gene, measured by nucleotide diversity, than VR. Low baseline viral nucleotide diversity (< 0.01) and high HBcrAg (≧ 2.0 KU/mL), but not HBsAg, at end of treatment (EOT) were significantly associated with higher risk of 1-year virological relapse (hazard ratio [HR] 6.09 and 3.31, respectively). Combination of low baseline viral nucleotide diversity and high HBcrAg at EOT could identify patients at high risk (HR 15.82). Further analysis of the evolution of HBV whole genome showed that HBV nucleotide diversity negatively correlated with serum HBV DNA levels. Notably, the viral quasispecies diversity between pre- and post-NA treatment remained relatively unchanged.

CONCLUSION

Higher baseline HBV quasispecies diversity associates with more durable off-therapy viral suppression in HBeAg-negative CHB patients. Combination of baseline viral nucleotide diversity and HBcrAg at EOT can identify patients at high risk for virological relapse after stopping NAs.

Combining end-of-treatment HBsAg and baseline hepatitis B core-related antigen reduce HBV relapse rate after tenofovir cessation

BACKGROUND/PURPOSE

The study investigated the role of hepatitis B core-related antigen (HBcrAg) in hepatitis B virus (HBV) relapse after stopping tenofovir disoproxil fumarate (TDF) in HBeAg-negative patients.

METHODS

A total of 185 HBeAg-negative patients without cirrhosis who had stopped TDF treatment for at least 6 months were recruited. All patients fulfilled the stopping criteria proposed by the Asian Pacific Association for the Study of the Liver 2012.

RESULTS

The 3-year cumulative incidences of virological relapse, clinical relapse, and hepatitis B surface antigen (HBsAg) loss were 72, 60.1 and 14.5%, respectively. End-of-treatment (EOT) HBsAg level was an independent predictor of virological relapse (hazard ratio (HR): 2.263; 95% confidence interval (CI): 1.779-2.887), clinical relapse (HR 1.773; 95% CI 1.367-2.298), and HBsAg loss (HR 0.179; 95% CI 0.096-0.335). Among patients who had HBsAg < 100 and ≥ 100 IU/mL, the 3-year virological relapse rates were 37.4% and 85.3% (p < 0.001), clinical relapse rates were 30.3 and 71.7% (p < 0.001), and HBsAg loss rates were 40.6 and 2.6% (p < 0.001), respectively. Among the 53 patients with EOT HBsAg level < 100 IU/mL, the 3-year virological relapse rates in patients with baseline HBcrAg levels < 4.7 and ≥ 4.7 log₁₀ U/mL were 20.3 and 60.4% (p = 0.003), and the clinical relapse rates were 10.3 and 59.5% (p < 0.001) respectively. Additionally, the 3-year HBsAg loss rates in patients with baseline HBcrAg ≤ 3 and > 3 log₁₀ U/mL were 42.9 and 7.9% (p < 0.001).

CONCLUSIONS

The combination of EOT HBsAg and baseline HBcrAg levels could further reduce the risk of HBV relapse after stopping TDF therapy in HBeAg-negative patients.

HBeAg-positive patients with HBsAg < 100 IU/mL and negative HBV RNA have lower risk of virological relapse after nucleos(t)ide analogues cessation

BACKGROUND

Nucleos(t)ide analogues (NAs) cessation is not widely practiced and remains a controversial, but highly relevant subject in patients infected with hepatitis B virus (HBV). We aimed to explore the related factors for safe NAs cessation.

METHODS

This is a multicenter prospective cohort study. Overall, 139 initially HBV e antigen (HBeAg)-positive patients meeting the stopping criteria were included in 12 hospitals in China. Enrolled patients ceased NAs and were followed up every 3 months for 24 months or until clinical relapse (CR).

RESULTS

The 24 month cumulative rates of virological relapse (VR), CR, HBeAg reversion and HBV surface antigen (HBsAg) loss were 50.4, 24.5, 11.5 and 9.4%, respectively. Patients with end of treatment (EOT) HBsAg  < 100 IU/mL plus negative HBV RNA had the lowest 24 month cumulative VR rate (5 vs 58%, p < 0.001). EOT HBsAg  ≥ 2 log₁₀ IU/mL [odds ratio (OR) = 6.686, p = 0.006], EOT positive HBV RNA (OR = 3.453, p = 0.008) and EOT hepatitis B core-related antigen (HBcrAg)  ≥ 4log U/mL (OR = 3.702, p = 0.002) were found to independently predict the risk of VR. To predict VR, the area under the receiver-operating characteristic (AUROC) value of the EOT HBsAg  < 100 IU/mL plus EOT HBV RNA negative was 0.698 (p < 0.001), which was higher than other parameters alone or combinations.

CONCLUSIONS

NAs cessation is suitable only for a small and selected patients. An EOT HBsAg  < 100 IU/mL and EOT negative HBV RNA identified a patient with low risk of off-treatment VR.