Serum HBV RNA and HBeAg are useful markers for the safe discontinuation of nucleotide analogue treatments in chronic hepatitis B patients

Phase 1 trial of the safety, pharmacokinetics, and antiviral activity of EDP-514 in untreated viremic chronic hepatitis B patients

BACKGROUND/AIMS

Oral EDP-514 is a potent core protein inhibitor of hepatitis B virus (HBV) replication, which produced a >4-log viral load reduction in HBV-infected chimeric mice with human liver cells. This study evaluated the safety, pharmacokinetics, and antiviral activity of three doses of EDP-514 in treatment-naive viremic patients with HBeAgpositive or -negative chronic HBV infection.

METHODS

Patients with HBsAg detectable at screening and at least 6 months previously were eligible. HBeAg-positive and -negative patients had a serum/plasma HBV DNA level ≥20,000 and ≥2,000 IU/mL, respectively. Twenty-five patients were randomized to EDP-514 200 (n=6), 400 (n=6) or 800 mg (n=7) or placebo (n=6) once daily for 28 days.

RESULTS

A dose-related increase in EDP-514 exposure (AUClast and Cmax) was observed across doses. At Day 28, mean reductions in HBV DNA were -2.9, -3.3, -3.5 and -0.2 log10 IU/mL with EDP-514 200 mg, 400 mg, 800 mg, and placebo groups, respectively. The corresponding mean change from baseline for HBV RNA levels was -2.9, -2.4, -2.0, and -0.02 log10 U/mL. No virologic failures were observed. No clinically meaningful changes from baseline were observed for HBsAg, HBeAg or HBcrAg. Nine patients reported treatment emergent adverse events of mild or moderate severity with no discontinuations, serious AEs or deaths.

CONCLUSION

In treatment-naïve viremic patients, oral EDP-514 was generally safe and well-tolerated, displayed PK profile supportive of once-daily dosing, and markedly reduced HBV DNA and HBV RNA.

Quantitative Measurement of Serum HBcrAg Can Be Used to Assess the Feasibility of Safe Discontinuation of Antiviral Therapy for Chronic Hepatitis B

Hepatitis B virus (HBV) infection is a serious global health problem, and chronic HBV infection significantly increases the risk of liver fibrosis, cirrhosis, and even hepatocellular carcinoma in patients. Current first-line therapeutics such as nucleos(t)ide analogues and interferons are unable to completely clear cccDNA, so the vast majority of patients need to take long-term or even lifelong medication. However, long-term virological and biochemical responses can be achieved in some patients after drug withdrawal. Successfully screening these patients with drug withdrawal advantages is difficult. Hepatitis-B-core-related antigen (HBcrAg) is a new HBV serological marker that which can reflect the level and transcription activity of cccDNA in hepatocytes. Therefore, HBcrAg has potential value in guiding patients in drug withdrawal. This review summarizes previous reports on HBcrAg and evaluates the application value of HBcrAg in safe drug discontinuation.

Selective detection of HBV pre-genomic RNA in chronic hepatitis B patients using a novel RT-PCR assay

In chronic hepatitis B (CHB) patients, quantification of HBV pgRNA in plasma has the potential to provide information on disease prognosis and liver injury or histopathology. However, current methods for detecting HBV pgRNA present technical difficulties due to the co-existence of HBV DNA in plasma samples. We have successfully established a novel one-step RT-PCR assay that allows selective quantification of HBV pgRNA. Two cohorts of participants were recruited for assay validation, including treatment-naïve patients with CHB and HBeAg-positive CHB patients who were treated with Tenofovir and monitored for 6 months to assess the predictive value of baseline HBV RNA for HBeAg seroclearance. Statistical analysis was performed using MedCalc version 20.019 software. The novel selective one-step RT-PCR assay for detecting HBV pgRNA was validated with a limit of detection of 100 copies/mL. The assay was able to selectively measure HBV pgRNA even in the presence of excess HBV rcDNA. In treatment-naïve CHB patients, HBV pgRNA levels were significantly lower than HBV DNA concentration. Serum HBV DNA levels and HBeAg status were positively associated with HBV pgRNA. Baseline serum HBV pgRNA levels were found to be strong predictors of HBeAg seroclearance after 6 months of Tenofovir treatment. The study presents a novel RT-PCR assay that allows accurate measurement of plasma HBV pgRNA in chronic hepatitis B patients, even in the presence of excess HBV DNA. The assay is highly selective and represents a significant advancement with potential for further breakthroughs in understanding the clinical significance of HBV pgRNA.

Serum HBV RNA levels among untreated adults with chronic hepatitis B in distinct immune phases and liver histopathology statuses

HBV RNA is a novel serum biomarker that reflects intrahepatic HBV covalently closed circular DNA (cccDNA) transcription activity. Serum HBV RNA levels among treatment-naïve adults during the natural history of chronic hepatitis B (CHB) and distinct liver histopathology statuses remain elusive. In our study, we include a total of 411 treatment-naïve CHB patients, among which 43 patients were HBeAg-positive immune-tolerant [IT(e+)], 84 patients were HBeAg-positive immune active [IA(e+)], 65 patients in HBeAg-negative immune active phases [IA(e-)], 149 patients were HBeAg-negative inactive phases [IC(e-)], and 70 patients were in Gray Zone (GZ). HBV RNA was measured in this cohort and its potential correlation with traditional serological markers and liver histopathology were analyzed. Our data showed that HBV RNA was strongly correlated with HBV DNA, HBeAg, HBsAg and ALT. Further subgroup analysis revealed a close correlation between HBV RNA and HBV DNA in patients in the IA (e+) and IA (e-) phases, but neither in IT(e+) nor IC(e-) phase. HBV RNA levels were consistently increased with the advanced degrees of hepatic inflammation, but not hepatic fibrosis. Of note, HBV RNA from HBeAg-positive patients negatively correlated with liver fibrosis, whereas HBV RNA from HBeAg-negative patients was weakly associated with liver inflammation. To sum up, serum HBV RNA shows a distinct profile among CHB patients in different immune statuses and hepatic histopathology stages/grades. Simultaneous testing of HBV RNA and traditional indicators might provide a comprehensive clinical assessment of CHB patients.

Hepatitis B virus serum RNA transcript isoform composition and proportion in chronic hepatitis B patients by nanopore long-read sequencing

Introduction

Serum hepatitis B virus (HBV) RNA is a promising new biomarker to manage and predict clinical outcomes of chronic hepatitis B (CHB) infection. However, the HBV serum transcriptome within encapsidated particles, which is the biomarker analyte measured in serum, remains poorly characterized. This study aimed to evaluate serum HBV RNA transcript composition and proportionality by PCR-cDNA nanopore sequencing of samples from CHB patients having varied HBV genotype (gt, A to F) and HBeAg status.

Methods

Longitudinal specimens from 3 individuals during and following pregnancy (approximately 7 months between time points) were also investigated. HBV RNA extracted from 16 serum samples obtained from 13 patients (73.3% female, 84.6% Asian) was sequenced and serum HBV RNA isoform detection and quantification were performed using three bioinformatic workflows; FLAIR, RATTLE, and a GraphMap-based workflow within the Galaxy application. A spike-in RNA variant (SIRV) control mix was used to assess run quality and coverage. The proportionality of transcript isoforms was based on total HBV reads determined by each workflow.

Results

All chosen isoform detection workflows showed high agreement in transcript proportionality and composition for most samples. HBV pregenomic RNA (pgRNA) was the most frequently observed transcript isoform (93.8% of patient samples), while other detected transcripts included pgRNA spliced variants, 3' truncated variants and HBx mRNA, depending on the isoform detection method. Spliced variants of pgRNA were primarily observed in HBV gtB, C, E, or F-infected patients, with the Sp1 spliced variant detected most frequently. Twelve other pgRNA spliced variant transcripts were identified, including 3 previously unidentified transcripts, although spliced isoform identification was very dependent on the workflow used to analyze sequence data. Longitudinal sampling among pregnant and post-partum antiviral-treated individuals showed increasing proportions of 3' truncated pgRNA variants over time.

Conclusions

This study demonstrated long-read sequencing as a promising tool for the characterization of the serum HBV transcriptome. However, further studies are needed to better understand how serum HBV RNA isoform type and proportion are linked to CHB disease progression and antiviral treatment response.

Human immunodeficiency virus coinfection differentially impacts hepatitis B virus viral markers based on hepatitis Be antigen status in patients with suppressed viremia

Hepatitis B virus (HBV) RNA and hepatitis B core-related antigen (HBcrAg), reflecting transcriptional activity of covalently closed circular DNA, are gaining traction as important markers to assess viral activity. Whether their expression differs under viral suppression by HIV co-infection status is unknown. Among adults with chronic HBV on antiviral therapy, we sought to determine if the expression of HBV markers (specialized and well-established) differs between HBV-HIV co-infection vs. HBV mono-infection. We compared HBV marker levels among 105 participants in the Hepatitis B Research Network (HBRN) HBV-HIV Ancillary Study and 105 participants in the HBRN mono-infected Cohort Study, matched for HBeAg status and HBV DNA suppression on therapy. Among HBeAg+ participants (N = 58 per group), after adjusting for age, sex, race, ALT and HBV DNA, viral markers were higher (p < .05) in the HBV-HIV versus the HBV-only sample (HBeAg: 1.05 vs. 0.51 log10 IU/mL; HBsAg: 3.85 vs. 3.17 log10 IU/mL; HBV RNA: 5.60 vs. 3.70 log10 U/mL; HBcrAg: 6.59 vs. 5.51 log10 U/mL). Conversely, among HBeAg(-) participants (N = 47 per group), HBsAg (2.00 vs. 3.04 log10 IU/mL) and HBV RNA (1.87 vs. 2.66 log10 U/mL) were lower (p < .05) in HBV-HIV vs. HBV-only; HBcrAg levels were similar (4.14 vs. 3.64 log10 U/mL; p = .27). Among adults with chronic HBV with suppressed viremia on antiviral therapy, viral markers tracked with HIV co-infection status and associations differed inversely by HBeAg status. The greater sensitivity and specificity of HBV RNA compared to HBcrAg allows for better discrimination of transcriptional activity regardless of HBeAg status.

Baseline serum HBV RNA is associated with the risk of hepatitis flare after stopping nucleoside analog therapy in HBeAg-negative participants

BACKGROUND AND AIMS

HBV RNA in peripheral blood reflects HBV cccDNA transcriptional activity and may predict clinical outcomes. The prospective Melbourne HBV-STOP trial studied nucleot(s)ide analog discontinuation in HBeAg-negative non-cirrhotic participants with long-term virological suppression. Ninety-six weeks after stopping treatment, the proportion of participants with virological relapse (HBV DNA > 2000 IU/mL), biochemical relapse (ALT > 2 × ULN and HBV DNA > 2000 IU/mL), or hepatitis flare (ALT > 5 × ULN and HBV DNA > 2000 IU/mL) was 89%, 58%, and 38%, respectively. We evaluated the ability of serum HBV RNA levels to predict these outcomes.

APPROACH RESULTS

HBV RNA levels were measured using the Roche cobas 6800/8800 HBV RNA Investigational Assay. Sixty-five participants had baseline and longitudinal off-treatment specimens available for RNA testing. HBV RNA was detectable at baseline in 25% of participants and was associated with a higher risk of biochemical relapse (81% vs. 51%, p value 0.04) and hepatitis flare (63% vs. 31%, p value 0.04). Participants who had undetectable serum HBV RNA as well as HBsAg ≤ 100 IU/mL at baseline were less likely to experience virological relapse (4 of 9, 44%) than participants with detectable HBV RNA and HBsAg level > 100 IU/mL (15/15, 100%; p value 0.0009). Off-treatment levels of HBV RNA were correlated with HBV DNA and were associated with the risk of hepatitis flare.

CONCLUSIONS

Serum HBV RNA may be a useful biomarker for guiding clinical decision-making before stopping nucleot(s)ide analog therapy. Baseline HBV RNA and HBsAg levels are associated with the risk of clinical relapse, hepatitis flare, and disease remission off-treatment.

Assessment of the cobas® HBV RNA investigational assay in the setting of nucleoside analog therapy cessation

HBV RNA is used as a marker of cccDNA transcription and is applicable in the setting of nucleos(t)ide analog (NA) treatment, which suppresses HBV DNA. Traditional assays for quantification of HBV RNA rely on labor-intensive 3'RACE assays targeting the polyA tail. In this study, the high-throughput Roche cobas®HBV RNA investigational assay was assessed on the Roche cobas® 6800 automated platform. Of 969 samples collected for a NA treatment cessation trial, and tested on the cobas assay, 249 were analyzed for sensitivity, reproducibility, sample type applicability, and results were compared to a RACE-based assay. Results of 97 paired serum and plasma samples demonstrated an excellent correlation of 0.98. However, 14.5% of plasma samples yielded detectable (below the limit of quantification) results, when the paired serum was undetectable, and plasma was shown to yield a statistically significant (p < 0.001) greater mean 0.119 log₁₀ copies/ml. Quantification of 152 samples showed good correlation (0.91) between the cobas and RACE assays. The cobas assay demonstrated superior lower limit of quantification, 10 copies/ml, which resulted in detection of 13.2% more samples than the RACE assay. Reproducibility and linear range of the automated assay were also confirmed. The Roche cobas assay for HBV RNA is sensitive and highly recommended.

EDP-514 in healthy subjects and nucleos(t)ide reverse transcriptase inhibitor-suppressed patients with chronic hepatitis B

Background

Chronic hepatitis B (CHB) remains a major cause of morbidity and mortality. EDP-514 is a potent core inhibitor of hepatitis B virus (HBV) that reduces viral load reduction in HBV-infected chimeric mice. This first-in-human study evaluated the safety, tolerability, and pharmacokinetics (PK) of EDP-514 in healthy subjects and antiviral activity in patients with CHB.

Methods

In Part 1, 82 subjects received placebo or EDP-514 in fed or fasted state as single ascending doses of 50–800 mg and multiple ascending doses of 200–800 mg for 14 days. In Part 2, 24 HBV DNA-suppressed, nucleos(t)ide (NUC)-treated (i.e., NUC-suppressed) CHB patients received EDP-514 200–800 mg or placebo for 28 days.

Results

EDP-514 was well tolerated in healthy subjects and CHB patients with most adverse events of mild intensity. In Part 1, EDP-514 exposure increased in an approximately dose proportional manner up to 600 mg after single doses and up to 400 mg after 14-day dosing. In Part 2, EDP-514 exposure increased linearly with dose on Day 1 and Day 28, with some accumulation for Day 28 and median trough concentrations (Ctrough) approximately 20-fold above the protein-adjusted 50% effective concentration (EC50) for the dose range. Mean change in HBV RNA from baseline to Day 28 was −2.03, −1.67, −1.87, and −0.58 log U/mL in the 200 mg, 400 mg, 800 mg, and placebo CHB groups, respectively.

Conclusions

EDP-514 was well tolerated, had a PK profile supporting once daily dosing, and reduced HBV RNA levels in NUC-suppressed CHB patients.

A roadmap for serum biomarkers for hepatitis B virus: current status and future outlook

Globally, 296 million people are infected with hepatitis B virus (HBV), and approximately one million people die annually from HBV-related causes, including liver cancer. Although there is a preventative vaccine and antiviral therapies suppressing HBV replication, there is no cure. Intensive efforts are under way to develop curative HBV therapies. Currently, only a few biomarkers are available for monitoring or predicting HBV disease progression and treatment response. As new therapies become available, new biomarkers to monitor viral and host responses are urgently needed. In October 2020, the International Coalition to Eliminate Hepatitis B Virus (ICE-HBV) held a virtual and interactive workshop on HBV biomarkers endorsed by the International HBV Meeting. Various stakeholders from academia, clinical practice and the pharmaceutical industry, with complementary expertise, presented and participated in panel discussions. The clinical utility of both classic and emerging viral and immunological serum biomarkers with respect to the course of infection, disease progression, and response to current and emerging treatments was appraised. The latest advances were discussed, and knowledge gaps in understanding and interpretation of HBV biomarkers were identified. This Roadmap summarizes the strengths, weaknesses, opportunities and challenges of HBV biomarkers.

Change of Cytokines in Chronic Hepatitis B Patients and HBeAg are Positively Correlated with HBV RNA, Based on Real-world Study

BACKGROUND AND AIMS

The natural course of chronic hepatitis B virus (HBV) infection is widely studied; however, follow-up studies of the same patients are scanty. Here, we studied the dynamic changes of serum HBV RNA and cytokines in hepatitis B virus e antigen (HBeAg)-positive patients treated with entecavir (ETV) to explore the relationship between the HBV serum viral nucleic acids and host immunity.

METHODS

Thirty-three chronic hepatitis B patients who are HBeAg-positive, with high virus load (HBV DNA >20,000 IU/mL), and received standard nucleos(t)ide analogue (NA) antiviral therapy (ETV) for more than 48 weeks were included. The serum levels of HBV nucleic acids and selected cytokines were measured at 0, 12, 24, and 48 weeks respectively.

RESULTS

Serum HBV RNA could still be detected while serum HBV DNA had fallen below the detection limit in patients treated with ETV. There was a strong positive correlation between HBV RNA and HBeAg, with a concomitant decrease in the secretion of cytokines from type 1 helper T (Th1)/type 2 helper T (Th2)/interleukin (IL)-17 producing T (Th17) cells. IL-4 and IL-10 were the main cytokines negatively associated with serum HBV RNA.

CONCLUSIONS

HBeAg can be used to reflect the load of HBV RNA indirectly, because serum HBV RNA has not been widely used in clinical practice. Meanwhile, serum IL-4 and IL-10 might be explored in combination with HBV RNA in guiding future clinical antiviral therapy.

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.

Hepatitis B surface antigen and hepatitis B RNA changes in HIV/hepatitis B virus co-infected participants receiving hepatitis B virus-active antiretroviral therapy

INTRODUCTION

With advances in hepatitis B virus (HBV) therapies, there is a need to identify serum biomarkers that assess the HBV covalently closed circular DNA (cccDNA) reservoir and predict functional cure in HIV/HBV co-infection.

METHODS

In this retrospective study, combining samples from HIV/HBV co-infected participants enrolled in two ACTG interventional trials, proportions achieving HBsAg less than 0.05 log10 IU/ml and HBV RNA less than log10 1.65 U/ml or not detected (LLoQ/NEG) in response to DUAL [tenofovir TDF+emtricitabine (FTC)] vs. MONO [FTC or lamivudine (3TC)] HBV-active ART, were measured. Predictors of qHBsAg less than 0.05 log10 IU/ml were evaluated in logistic regression models.

RESULTS

There were 88 participants [58% women, median age 34; 47 on DUAL vs. 41 on MONO HBV-active ART]. Twenty-one percent achieved HBsAg less than 0.05 log10 IU/ml (30% DUAL vs. 10% MONO). Time to HBsAg less than 0.05 log10 IU/ml was lower (P  = 0.02) and the odds of achieving HBsAg less than 0.05 log10 IU/ml were higher (P = 0.07) in DUAL participants. HBV RNA became less than LLoQ/NEG in 47% (DUAL 60% vs. MONO 33%). qHBsAg less than 3 log10 IU/ml was the strongest predictor of HBsAg less than 0.05 log10 IU/ml.

CONCLUSION

This study supports current recommendations of TDF-based DUAL-HBV active ART for initial use in HIV/HBV co-infection. HBV RNA could be a useful marker of treatment response in HIV/HBV co-infected patients on HBV-active ART.

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.

Dynamics of Serum Pregenome RNA in Chronic Hepatitis B Patients Receiving 96-Month Nucleos(t)ide Analog Therapy

Background

Tissue covalently closed circular DNA (cccDNA) can reflect the activity of HBV replication. However, it is impractical to assess intrahepatic cccDNA in every outpatient. Serum pregenome RNA (pgRNA) is transcribed from intrahepatic cccDNA and may reflect the activity of intrahepatic cccDNA. We explored the dynamics and the potential role of serum pgRNA in patients receiving long-term NAs treatment.

Methods

Serum pgRNA, HBV DNA, HBsAg, HBeAg, and ALT levels were quantified, and the relationships between serum pgRNA and these common clinical indicators before and after the treatment were investigated.

Results

Serum pgRNA showed dynamic change during the 96-month NAs therapy, and serum pgRNA levels were positive and detectable in 19 patients with undetectable serum HBV DNA. Serum pgRNA showed strong and positive correlation with serum HBV DNA (r = 0.693, p < 0.001) and serum HBsAg levels (r = 0.621, p < 0.001) at baseline. Patients with HBeAg seroconversion had lower baseline serum pgRNA levels (p = 0.002). The area under the curve (AUC) of baseline serum pgRNA for predicting HBeAg seroconversion was 0.742 (95% CI: 0.606–0.850) with 63.16% sensitivity and 80.56% specificity. The cumulative HBeAg seroconversion rate was higher in patients with low serum pgRNA (p = 0.001).

Conclusion

Serum pgRNA of low level at baseline or great decline at month 6 may independently predict the high incidence of undetectable serum pgRNA at year 4 following NAs therapy, and the baseline serum pgRNA may serve as a novel predictor for HBeAg seroconversion during NAs therapy.

Analysis of serum hepatitis B virus RNA levels among HBsAg and HBsAb copositive patients and its correlation with HBV DNA

ABSTRACT

There are approximately 2 billion HBV-infected individuals worldwide, and approximately 1.87% to 7% of these individuals are copositive for HBsAg and HBsAb.Our study detected hepatitis B virus pgRNA (HBV RNA) levels in HBsAg and HBsAb copositive patients and then analyzed the correlation with HBV DNA, HBsAg, ALT, and AST levels. A total of 149 HBsAg and HBsAb copositive patients were identified from 66,617 outpatients.HBV RNA, HBV DNA, HBsAg, ALT, and AST serum levels were significantly different in different natural phases of HBV infection (immune tolerance phase, immune clearance phase, low replication phase, and reactivation phase) with statistical significance (P < .01). HBV RNA levels were positively correlated with HBV DNA, HBsAg, ALT, and AST levels. HBV RNA and HBV DNA levels were significantly increased in the HBeAg-positive group (66 patients) compared with the HBeAg-negative group (83 patients) (P < .01). In the HBeAg-positive group, HBV RNA levels were positively correlated with HBV DNA and HBsAg levels. In the HBeAg-negative group, HBV RNA levels were positively correlated with HBV DNA. Serum HBV RNA levels were positively correlated with HBV DNA, HBsAg, ALT, and AST levels.HBV RNA could be used as a virological indicator for antiviral therapy in HBsAg and HBsAb copositive hepatitis B patients.

On-treatment HBV RNA dynamic predicts entecavir-induced HBeAg seroconversion in children with chronic hepatitis B

BACKGROUND

Hepatitis B e antigen (HBeAg) seroconversion is an important intermediate outcome in HBeAg-positive chronic hepatitis B patients. This study aimed to explore whether hepatitis B virus (HBV) RNA serum levels can predict HBeAg seroconversion treated with entecavir.

METHODS

Serum samples from HBeAg-positive children previously treated with entecavir were retrospectively analyzed. HBV RNA levels were measured at baseline, weeks 12, 24, 48, 72 of therapy. Ability of individual biomarkers to predict HBeAg seroconversion was evaluated using receiver operating characteristics (ROC) analyzes.

RESULTS

Serum HBV RNA was detectable in 51 children with a median of 6.05 (4.04-8.29) log₁₀ IU/mL at baseline. Patients with subsequent HBeAg seroconversion showed a significantly larger decline in median HBV RNA levels during treatment from baseline to week 12 of 1.96 (0.30-3.38) and to week 24 of 2.27 (1.20-3.38) log₁₀ IU/mL, respectively, in comparison to HBeAg-positive patients without HBeAg seroconversion (P < 0.001). Levels of HBV RNA at treatment weeks 12 and 24 showed good ability to predict HBeAg seroconversion (area under ROC scores > 0.85, P < 0.001).

CONCLUSION

On-treatment HBV RNA dynamic predicts entecavir-induced HBeAg seroconversion in children with chronic hepatitis B living in China.

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.

Serum hepatitis B virus RNA level is associated with biochemical relapse in patients with chronic hepatitis B infection who discontinue nucleos(t)ide analogue treatment

BACKGROUND

Nucleos(t)ide analogue (NA) discontinuation may be attempted in carefully selected patients with chronic hepatitis B (CHB) infection.

AIM

To investigate whether a novel serum marker of quantitative hepatitis B virus (HBV) RNA levels could predict biochemical relapse after NA discontinuation.

METHODS

We prospepctively followed non-cirrhotic Asian patients with CHB who stopped NA according to pre-specified stopping criteria. The primary endpoint was biochemical relapse (HBV DNA >2000 IU/mL and alanine transaminase >2x upper limit of normal), which were also the re-treatment criteria.

RESULTS

Biochemical relapse occurred in 50 patients (48.3% at year 6). Multivariable analysis showed that higher HBV RNA levels (HR 1.34; P < 0.001) at the time of NA discontinuation were associated with increased biochemical relapse risk. The area under the curve of HBV RNA at the time of NA discontinuation for the incidence of biochemical relapse was 0.760 at 6 years. Six years after treatment discontinuation, all patients with HBV RNA levels ≥20 000 copies/mL at the end of treatment developed a biochemical relapse compared with 23.8% of patients with HBV RNA levels<1000 copies/mL (P < 0.001). More patients with HBV RNA levels <1000 copies/mL at end of treatment achieved loss of hepatitis B surface antigen than patients with higher levels (30.9% vs 1.6%; P = 0.027).

CONCLUSIONS

The HBV RNA level at end of treatment predicted biochemical relapse after treatment discontinuation and may be used to guide decisions on treatment discontinuation.

Advances in treatment and prevention of hepatitis B

Chronic hepatitis B (CHB) continues to contribute to worldwide morbidity and mortality significantly. Scientists, clinicians, pharmaceutical companies, and health organizations have dedicated substantial Intellectual and monetary resources to finding a cure, increasing immunization rates, and reducing the global burden of CHB. National and international health-related organizations including the center for disease control, the national institute of health, the American Association for the study of liver disease (AASLD), The European association for the study of the Liver (EASL), The Asia Pacific association for the study of the Liver (APASL) and the world health organization release periodic recommendations for disease prevention and treatment. Our review of the most recent guidelines by EASL, AASLD, APASL, and Taiwan Association for the Study of the Liver revealed that an overwhelming majority of cited studies were published before 2018. We reviewed Hepatitis B-related literature published 2018 onwards to identify recent developments and current barriers that will likely direct future efforts towards eradicating hepatitis B. The breakthrough in our understanding of the hepatitis B virus life cycle and resulting drug development is encouraging with significant room for further progress. Data from high-risk populations, most vulnerable to the devastating effects of hepatitis B infection and reactivation remain sparse. Utilization of systems approach, optimization of experimental models, identification and validation of next-generation biomarkers, and precise modulation of the human immune response will be critical for future innovation. Within the foreseeable future, new treatments will likely complement conventional therapies rather than replace them. Most Importantly, pragmatic management of CHB related population health challenges must be prioritized to produce real-world results.

HBV RNA Profiles in Patients With Chronic Hepatitis B Under Different Disease Phases and Antiviral Therapy

BACKGROUND AND AIMS

Large-scale comprehensive studies on HBV RNA in chronic hepatitis B are lacking. We aimed to study the HBV RNA profile and its correlation with other viral markers in patients with chronic hepatitis B who are treatment-naïve and patients receiving nucleos(t)ide analogues (NA).

APPROACH AND RESULTS

Biomarkers, including HBV RNA and hepatitis B core-related antigen (HBcrAg), were measured in 388 patients. Of these, 246 were treatment-naïve and were categorized into HBeAg-positive chronic infection (n = 41), HBeAg-positive chronic hepatitis (n = 81), HBeAg-negative chronic infection (n = 39), HBeAg-negative chronic hepatitis (n = 66), and HBsAg seroclearance (n = 19). These biomarkers were also measured in 142 patients who were NA-treated receiving tenofovir or entecavir at baseline, week 48, and week 96. The pattern of serum HBV RNA levels mirrored HBV DNA (1-2 logs higher than HBV RNA) and HBcrAg in patients who were treatment-naïve. HBV RNA correlated best with HBcrAg (r = 0.84) and to a lesser extent with HBV DNA (r = 0.737) (both P < 0.001). In patients with HBsAg seroclearance, 15.8% and 15.8% had detectable serum HBV RNA and HBcrAg, respectively. NA treatment reduced serum HBV RNA by 1.46 logs and 1.77 logs at weeks 48 and 96, respectively. At week 96 of NA therapy, only 19.1% patients who were tenofovir-treated and 25.7% patients who were entecavir-treated had unquantifiable HBV RNA (P > 0.05). In patients who were treated and had undetectable HBV DNA, 77.5% and 30% had quantifiable HBV RNA and HBcrAg, respectively.

CONCLUSIONS

HBV RNA showed distinct and corresponding profiles in patients with HBV in different disease phases. HBV RNA and HBcrAg could be used to monitor residual transcriptional activities in patients with HBsAg seroclearance. NA led to reduction of serum HBV RNA. Monitoring of viral activities can still be achieved in patients with undetectable HBV DNA by serum HBV RNA.

Novel Biomarkers of Hepatitis B Virus and Their Use in Chronic Hepatitis B Patient Management

Even though an approved vaccine for hepatitis B virus (HBV) is available and widely used, over 257 million individuals worldwide are living with chronic hepatitis B (CHB) who require monitoring of treatment response, viral activity, and disease progression to reduce their risk of HBV-related liver disease. There is currently a lack of predictive markers to guide clinical management and to allow treatment cessation with reduced risk of viral reactivation. Novel HBV biomarkers are in development in an effort to improve the management of people living with CHB, to predict disease outcomes of CHB, and further understand the natural history of HBV. This review focuses on novel HBV biomarkers and their use in the clinical setting, including the description of and methodology for quantification of serum HBV RNA, hepatitis B core-related antigen (HBcrAg), quantitative hepatitis B surface antigen (qHBsAg), including ultrasensitive HBsAg detection, quantitative anti-hepatitis B core antigen (qAHBc), and detection of HBV nucleic acid-related antigen (HBV-NRAg). The utility of these biomarkers in treatment-naïve and treated CHB patients in several clinical situations is further discussed. Novel HBV biomarkers have been observed to provide critical clinical information and show promise for improving patient management and our understanding of the natural history of HBV.

Stability of hepatitis B virus pregenomic RNA in plasma specimens under various temperatures and storage conditions

Background

Hepatitis B virus (HBV) pregenomic RNA (pgRNA) has gained increasing attention owing to its role in replication of covalently closed circular DNA (cccDNA) in HBV. This marker has the potential to be used in clinical programs aimed to manage HBV infections. However, several reports on HBV pgRNA levels in clinical cases have conflicting results. RNA is easily degraded when exposed to heat and other environmental stressors. However, the stability of HBV pgRNA, during blood sample collection before the standard automated quantification, has never been estimated. This study aimed to demonstrate the effect of two different temperature conditions and storage durations on the stability of HBV pgRNA.

Method

Blood from forty patients with chronic hepatitis B infection, who also showed evidence of active HBV DNA replication, was collected and processed within 2 h of collection. Plasma from each patient was divided and stored at 4 °C and 25 °C (room temperature) for six different storage durations (0, 2, 6, 12, 24, and 48 h) and subsequently transferred to −80 °C for storage. The effect of multiple cycles of freezing and thawing of plasma at −20 °C or −80 °C was evaluated using samples from ten patients. Quantification of pgRNA from the samples was performed simultaneously, using the digital polymerase chain reaction (dPCR) method. The differences in pgRNA levels at baseline and each time point were compared using generalized estimating equation (GEE). A change greater than 0.5 log₁₀ copies/mL of pgRNA is considered clinically significant. Statistical analyses were conducted using Stata 16.0.

Results

The mean HBV pgRNA level in the initially collected plasma samples was 5.58 log₁₀copies/mL (ranging from 3.08 to 8.04 log₁₀ copies/mL). The mean pgRNA levels in samples stored for different time periods compared with the initial reference sample (time 0) significantly decreased. The levels of pgRNA for 6, 12, 24, and 48 h of storage reduced by −0.05 log₁₀ copies/mL (95% confidence interval (CI) −0.095 to −0.005, p = 0.03), −0.075 log₁₀ copies/mL (95% CI [−0.12 to −0.03], p = 0.001), −0.084 log₁₀ copies/mL (95% CI [−0.13 to −0.039], p =  < 0.001), and −0.120 log₁₀ copies/mL (95% CI [−0.17 to −0.076], p =  < 0.001), respectively. However, these changes were below 0.5 log₁₀ copies/mL and thus were not clinically significant. Compared with the samples stored at 4 °C, there were no significant differences in pgRNA levels in samples stored at 25 °C for any of the storage durations (−0.01 log₁₀ copies/mL; 95% CI [−0.708 to 0.689], p = 0.98). No significant difference in the levels of pgRNA was observed in the plasma samples, following four freeze-thaw cycles at −20 °C and −80 °C.

Conclusion

The plasma HBV pgRNA level was stable at 4 °C and at room temperature for at least 48 h and under multiple freeze-thaw cycles. Our results suggest that pgRNA is stable during the process of blood collection, and therefore results of pgRNA quantification are reliable.

Combining Hepatitis B Virus RNA and Hepatitis B Core-Related Antigen: Guidance for Safely Stopping Nucleos(t)ide Analogues in Hepatitis B e Antigen-Positive Patients With Chronic Hepatitis B

BACKGROUND

Safe nucleos(t)ide analogue discontinuation in chronic hepatitis B (CHB) is an unmet need. We aimed to investigate whether combining hepatitis B virus (HBV) RNA and hepatitis B core-related antigen (HBcrAg) could perform satisfactorily in predicting off-treatment outcomes.

METHODS

The evaluation cohort included 127 hepatitis B e antigen (HBeAg)-positive patients from a multicenter prospective trial who stopped telbivudine-based therapy after achieving HBeAg seroconversion and HBV DNA < 50 IU/mL for > 48 weeks. As validation, 59 patients treated with entecavir or tenofovir before discontinuation were analyzed.

RESULTS

At the end of treatment (EOT), HBV RNA and HBcrAg were significant independent predictors of the clinical relapse risk. In the evaluation cohort, no clinical relapse occurred among patients with negative HBV RNA and HBcrAg < 4 log10 U/mL at EOT (low-risk group), whereas 46.8% patients with positive HBV RNA and HBcrAg ≥ 4 log10 U/mL (high-risk group) experienced clinical relapse during 4-year posttreatment follow-up (P < .001); the corresponding incidences in the validation cohort were 0% and 69.4% (P < .001), respectively. More patients in the low-risk group achieved HBsAg loss than the other patients after treatment cessation (16.1% vs 1.3%, P = .002).

CONCLUSIONS

Combining HBV RNA and HBcrAg performed satisfactorily in predicting clinical relapse and HBsAg loss after treatment cessation in HBeAg-positive patients with CHB.The combination of hepatitis B virus RNA and hepatitis B core-related antigen performed satisfactorily in predicting clinical relapse and hepatitis B surface antigen loss after stopping nucleos(t)ide analogue treatment among noncirrhotic hepatitis B e antigen-positive patients with chronic hepatitis B and could be used to guide safe discontinuation.

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.

Deep sequencing analysis of serum hepatitis B virus-RNA during nucleot(s)ide analogue therapy

AIM

Recently, serum hepatitis B virus (HBV)-RNA has been reported to be detectable even when HBV particle production is inhibited by nucleot(s)ide analogues (NAs). However, the dynamics of the HBV-RNA sequence compared with those of HBV-DNA during the emergence of antiviral resistance are yet to be elucidated.

METHODS

First, we quantified serum HBV-RNA in 181 infected patients, and its relationships with clinical characteristics as well as HBV markers were investigated. Next, we undertook simultaneous deep sequencing of HBV-RNA/HBV-DNA and their dynamics among four patients receiving NA therapy who were experiencing viral breakthrough.

RESULTS

Serum HBV-RNA was detected in 25% (31/123) of cases among patients with HBV without NAs, and the detection rate was significantly high in hepatitis B e antigen-positive cases with high viral activity. In patients with chronic hepatitis, hepatitis B core-related antigen was significantly correlated with serum HBV-RNA irrespective of NA use. In the analysis of the four patients experiencing viral breakthrough, no NA resistance mutation was detected in the serum HBV-RNA immediately before the breakthrough. However, NA-resistant sequences appeared at the rates of 0%, 3%, 14%, and 100%, and the NA-resistant HBV-RNA sequence rate was correlated with the peak HBV-DNA titer multiplied by the HBV-DNA detection duration during the breakthrough (R²  = 0.978) observed before redisappearance of HBV-DNA following the addition of new NA.

CONCLUSION

Serum HBV-RNA could reflect the transcriptional activity of covalently closed circular DNA and hepatitis B core-related antigen. The dynamics of HBV-RNA could help understanding of the turnover process of HBV covalently closed circular DNA in the liver.

Hepatitis B Virus: From Diagnosis to Treatment

Hepatitis B infection is still a global concern progressing as acute-chronic hepatitis, severe liver failure, and death. The infection is most widely transmitted from the infected mother to a child, with infected blood and body fluids. Pregnant women, adolescents, and all adults at high risk of chronic infection are recommended to be screened for hepatitis B infection. The initial analysis includes serological tests that allow differentiation of acute and chronic hepatitis. Molecular assays performed provide detection and quantification of viral DNA, genotyping, drug resistance, and precore/core mutation analysis to confirm infection and monitor disease progression in chronic hepatitis B patients. All patients with chronic hepatitis B should be treated with antiviral medications and regularly monitored for efficient treatment. The current treatment is based on nucleos(t)ide analogs and pegylated interferons that save lives by decreasing liver cancer death, liver transplant, slow or reverse the progression of liver disease as well as the virus infectivity.

Single hepatocytes show persistence and transcriptional inactivity of hepatitis B

There is no cure for the more than 270 million people chronically infected with HBV. Nucleos(t)ide analogs (NUCs), the mainstay of anti-HBV treatment, block HBV reverse transcription. NUCs do not eliminate the intranuclear covalently closed circular DNA (cccDNA), from which viral RNAs, including pregenomic RNA (pgRNA), are transcribed. A key gap in designing a cure is understanding how NUCs affect HBV replication and transcription because serum markers yield an incomplete view of intrahepatic HBV. We applied single-cell laser capture microdissection and droplet digital PCR to paired liver biopsies collected from 5 HBV/HIV-coinfected persons who took NUCs over 2–4 years. From biopsy 1 to 2, proportions of HBV-infected hepatocytes declined with adherence to NUC treatment (P < 0.05); we extrapolated that eradication of HBV will take over 10 decades with NUCs in these participants. In individual hepatocytes, pgRNA levels diminished 28- to 73-fold during NUC treatment, corresponding with decreased tissue HBV core antigen staining (P < 0.01). In 4 out of 5 participants, hepatocytes with cccDNA but undetectable pgRNA (transcriptionally inactive) were present, and these were enriched in 3 participants during NUC treatment. Further work to unravel mechanisms of cccDNA transcriptional inactivation may lead to therapies that can achieve this in all hepatocytes, resulting in a functional cure.

Single-cell laser capture microdissection integrated with droplet digital PCR was used to study hepatocytes from individuals with chronic hepatitis B.

Serum HBV RNA Dynamic and Drug Withdrawal Predictor Value in Patients With Chronic HBV Infection on Long-term Nucleos(t)ide Analogue (NA) Therapy

AIMS

This study aimed to investigate the dynamic pattern of serum hepatitis B virus (HBV) RNA in chronic hepatitis B (CHB) patients on long-term nucleos(t)ide analogue (NA) therapy and evaluate predictor value of end-of-treatment (EOT) serum HBV RNA status on drug-withdrawal durability.

METHODS

We carried out a real-life cohort study of 326 CHB patients on NA treatment between February 12, 2016 and February 21, 2018. Thirty of these patients discontinued NA treatment after enrollment, and were included in 2-year off-therapy follow-up. Serum HBV RNA levels were determined using the RNA simultaneous amplification testing method.

RESULTS

Both serum HBV RNA and DNA levels declined significantly in long-term antiviral progress. When the treatment duration was longer than 3 years, the undetectable rates of HBV RNA and DNA were 55.10% and 97.0%, respectively. The serum HBV RNA-negative rate was 39.5%. The cumulative 2-year off-therapy viral and clinical relapse rate was 40.56%; 95% confidence interval (95% CI), 21.51-59.61 and 31.31%; 95% CI, 11.32-51.29 in all patients, respectively. Patients with EOT hepatitis B surface antigen (HBsAg)≤1000 IU/mL plus HBV RNA negativity had a relatively lower cumulative 2-year off-therapy viral relapse rate (23.01%; 95% CI, 0.17-45.99). EOT HBsAg≤1000 IU/mL plus HBV RNA negativity showed obvious superiority for the EOT HBsAg≤1000 IU/mL single in drug withdrawal durability prediction, with better specificity (18.18% vs. 72.73%, P=0.03), and the positive predictive value and negative predictive value were 76.92% and 47.06%, respectively.

CONCLUSIONS

In the long-term antiviral process, both serum HBV RNA and DNA levels declined significantly. EOT serum HBV RNA negativity was not an independent drug withdrawal marker, but can complement the HBsAg titer to monitor drug withdrawal in CHB patients on long-term NA therapy.

Efficacy of a combination of HBV RNA and HBeAg in predicting HBeAg seroconversion in patients treated with entecavir for 144 weeks

BACKGROUND

In some previous studies, serum hepatitis B virus RNA (HBV RNA) was proposed as an HBV viral marker during therapy. However, the dynamic change of HBV RNA, the correlation of HBV RNA with cccDNA, and the combination of HBV RNA with known HBV markers in predicting entecavir (ETV) treatment outcome in the same cohort are rarely reported.

METHODS

A total of 111 HBeAg-positive patients were enrolled in our study. The dynamic changes of serum HBV RNA and the correlation of HBV RNA with other HBV markers were investigated in the early treatment period of 144-week ETV treatment. Intrahepatic cccDNA was detected at baseline and week 48. Receiver operating characteristic analyses were used to identify HBV RNA levels associated with HBeAg seroconversion.

RESULTS

The serum HBV RNA levels decreased more rapidly in patients with HBeAg seroconversion than those without HBeAg seroconversion. The levels of HBV RNA decreased slower compared with the serum HBV DNA, irrespective of whether the patients achieved HBeAg seroconversion or not. Although the serum HBV RNA was positively correlated with cccDNA at baseline among all patients, no significant correlation was observed in the patients with HBeAg seroconversion at week 48 (r=0.094, P=0.588). The area under the receiver operating characteristic (AUROC) of HBV RNA and HBeAg at week 24 was 0.754 and 0.800, respectively. The AUROC of the HBV RNA and HBeAg combination had a higher value (AUROC=0.821).

CONCLUSIONS

The level of HBV RNA at week 24 was a powerful predictor of HBeAg seroconversion in HBeAg-positive patients after 144-week ETV treatment, while the combination of HBV RNA and HBeAg was superior to HBV RNA alone in predicting HBeAg seroconversion.

Monitoring of serum HBV RNA, HBcrAg, HBsAg and anti-HBc levels in patients during long-term nucleoside/nucleotide analogue therapy

BACKGROUND

This study was aimed at evaluating the clinical significance of serum HBV RNA, hepatitis B core-related antigen (HBcrAg) and hepatitis B core antibody (anti-HBc) levels in chronic hepatitis B patients with undetectable HBV DNA during nucleoside/nucleotide analogue (NA) treatment.

METHODS

Fifty-seven patients who received long-term NA treatment of median 5.83 (25%, 75% percentiles 4.67, 7.75) years were enrolled, and 285 serum samples at five time points for each patient were quantitatively analysed for the three serum markers together with serum HBV DNA and hepatitis B surface antigen (HBsAg) levels.

RESULTS

The HBV RNA level significantly correlated with HBcrAg (r=0.629; P<0.001) but not HBsAg levels (P=0.1460). Nonetheless, the HBcrAg level significantly correlated with the HBsAg level (r=0.469; P<0.001). Hepatitis B e antigen (HBeAg)-positive samples showed higher HBV RNA, HBcrAg and HBsAg levels than HBeAg-negative samples did (all P<0.05). Nine patients with HBeAg loss manifested a significantly greater decline in HBV RNA and HBcrAg levels (median 1.84 [25%, 75% percentiles 1.02, 2.12] log₁₀ copies/ml, 1.14 [0.62, 2.21] log₁₀ U/ml, respectively) compared with those in seven patients without HBeAg loss (0.74 [0.10, 1.08] log₁₀ copies/ml and 0.41 [0.21, 0.69] log₁₀ U/ml, respectively). Overall, serum HBV RNA, HBcrAg, HBsAg and anti-HBc levels gradually decreased with time during NA treatment. At the end of observation, HBV RNA and HBcrAg reached an undetectable level in 26 and 6 (46% and 11%) patients, respectively.

CONCLUSIONS

Monitoring of HBV RNA and HBcrAg levels is useful for NA-treated patients with undetectable HBV DNA. The attainment of HBV RNA undetectability usually occurs prior to HBcrAg undetectability.

New Biomarkers of Chronic Hepatitis B

Chronic hepatitis B (CHB) infection leads to clinically heterogeneous disease outcomes. Different viral markers are utilized to monitor treatment effects and predict risk of complications in patients with CHB. Hepatitis B core-related antigen (HBcrAg) is a novel serum composite viral protein whose performance has been proven to be superior to that of existing viral markers. It showed good correlation with intrahepatic covalently closed-circular DNA. Its profile differs drastically in patients in different disease phases, and the level declines with antiviral therapies. HBcrAg may be helpful for predicting hepatocellular carcinoma development and hepatitis B virus (HBV) reactivation in immunosuppressed patients. Another emerging measurable serum marker, HBV RNA, exists in the form of pregenomic RNA-containing virions. Its profile differs between patients in different disease phases in a similar manner to that of HBcrAg. HBV RNA is present in serum at lower levels than HBV DNA in treatment-naïve patients by 1–2 logs. In contrast, its level is higher than HBV DNA in patients receiving nucleos(t)ide analogues (NAs). A significant decline in serum RNA was observed in patients receiving novel antiviral therapies, including core protein allosteric modulators and RIG-1/NOD2 agonists. Both HBcrAg and HBV RNA may be helpful for predicting off-therapy sustained virological control in patients who stop long-term NA treatment.

3,4,5-Tri-O-caffeoylquinic acid methyl ester isolated from Lonicera japonica Thunb. Flower buds facilitates hepatitis B virus replication in HepG2.2.15 cells

Caffeoylquinic acids are well known for their prominent antiviral activities. Beyond our expectations, we initially found 3,4,5-Tri-O-caffeoylquinic acid methyl ester (3,4,5-CQME) from L. japonica can facilitate HBV DNA and antigens secretion. This study aimed to investigate its underlying molecular mechanism. The results indicate that 3,4,5-CQME signally increased intracellular and secreted HBsAg levels by more than two times in HepG2.2.15 cells and HepAD38 cells. Furthermore, levels of HBeAg, HBV DNA and RNA were significantly enhanced by 3-day 3,4,5-CQME treatment; it didn't directly affect intracellular cccDNA amount, although it slightly increased cccDNA accumulation as a HBV DNA replication feedback. In addition, treatment with 3,4,5-CQME significantly induced HBx protein expression for viral replication. We utilized a phospho-antibody assay to profile the signal transduction change by 3,4,5-CQME to illuminate its molecular mechanism. The results indicate that treatment with 3,4,5-CQME activated AKT/mTOR, MAPK and NF-κB pathways verified by immunoblot. Moreover, 3,4,5-CQME upregulated the expression of nuclear transcriptional factors PGC1α and PPARα. In short, 3,4,5-CQME promotes HBV transcription and replication by upregulating HBx expression and activating HBV transcriptional regulation-related signals. As caffeoylquinic acids are widely present in traditional Chinese medicines, the risk of intaking caffeoylquinic acids-containing herbs for hepatitis B treatment requires more evaluation and further research.

Rapidly decreased HBV RNA predicts responses of pegylated interferons in HBeAg-positive patients: a longitudinal cohort study

BACKGROUND

As an important anti-HBV drug, pegylated interferon α (PegIFNα) offers promising clinical efficacy, but biomarkers that accurately forecast treatment responses are yet to be elucidated. Here, we evaluated whether HBV RNA could act as an early monitor of pegylated interferon responses.

METHODS

We analyzed a phase 3, multicenter, randomized cohort of 727 HBeAg-positive non-cirrhotic patients receiving a 48-week treatment of PegIFNα-2a or PegIFNα-2b and a 24-week treatment-free follow-up. Serum levels of HBV RNA, HBV DNA, HBeAg, and HBsAg were measured at weeks 0, 12, 24, 48, and 72.

RESULTS

HBeAg seroconversion and HBsAg loss at week 72 were observed in 217 (29.8%) and 21 (2.9%) patients, respectively. During the 48-week treatment, HBV RNA decreased more rapidly than HBV DNA and HBsAg, but HBV RNA and HBeAg shared similar dynamics with positive correlations. Multivariate regression analyses consistently revealed the significance of HBV RNA at weeks 0, 12, 24, and 48 to monitor HBeAg seroconversion but not HBsAg loss. Although baseline HBV RNA only showed a modest AUC performance, HBV RNA with a significant increase of AUC at week 12 outperformed other HBV biomarkers to forecast HBeAg seroconversion (p value < 0.05). HBV RNA ≤ 1000 copies/mL was an optimized cutoff at week 12 that offered better prediction than other HBV biomarkers. This optimized cutoff plus patient age, HBV genotype B, and HBeAg offered a strong estimation of HBeAg seroconversion (accuracy 95.2%, true negative rate 99.8%).

CONCLUSION

HBV RNA at week 12 is an effective monitor of HBeAg seroconversion in HBeAg-positive patients treated with pegylated interferons.

Association Between Negative Results From Tests for HBV DNA and RNA and Durability of Response After Discontinuation of Nucles(t)ide Analogue Therapy

BACKGROUND & AIMS

There is no satisfactory way to identify patients who will maintain a response after discontinuation of nuleos(t)ide analogue therapy for chronic hepatitis B virus (HBV) infection. We investigated whether patients with negative results from tests for HBV DNA and HBV RNA (double negative) at the end of treatment maintain a long-term response to treatment.

METHODS

We performed a post-hoc analysis of data from a 2-year multi-center randomized controlled trial, and its long-term extension trials, on 130 patients with chronic HBV infection who were positive for the HB e antigen (HBeAg-positive; mean age, 30.8 ± 6.9 years; 72.3% male) and received telbivudine with or without adefovir and stopped therapy after they had HBeAg seroconversion and levels of HBV DNA <300 copies/mL for at least 48 weeks (evaluation cohort). Clinical and laboratory assessments were made every 12 or 16 weeks until clinical relapse (defined as HBV DNA > 2000 IU/mL and level of alanine aminotransferase more than 2-fold the upper limit of normal) or until 4 years off treatment. We validated our findings in a cohort of 40 HBeAg-positive patients (36.5 ± 9.4 years old; 72.5% male) treated with entecavir or tenofovir, and followed after discontinuation for up to 5.5 years. Patients were considered to be negative for HBV DNA if it was not detected in the COBAS Taqman assay. Patients were considered to be negative for HBV RNA if it was not detected by quantitative real-time PCR with 2 different pairs of primers.

RESULTS

After 4 years off treatment, in the evaluation cohort, 30.8% of patients had a clinical relapse, 54.7% had virologic relapse (HBV DNA >2000 IU/mL in 2 tests), and 16.8% had reappearance of HBeAg in 2 tests (reversion). A significantly lower proportion of double negative patients had a clinical relapse 4 years later (2/35; 8.0%) than of patients who tested positive for either HBV DNA or RNA (32/102; 31.4%; P = .018). In the validation cohort, after 5.5 years of follow up, a lower proportion of double negative patients had clinical relapse (2/13; 15.4%) than of patients who tested positive for either HBV DNA or RNA at the end of treatment (9/27; 33.3%; P = .286) CONCLUSIONS: In an analysis of data from 2 independent cohorts, we associated negative results from tests for HBV DNA and RNA (double negative) at the end of treatment with continued response 4 or more years after discontinuation of therapy in HBeAg-positive patients. These results might be used to identify the best candidates for discontinuation of nuleos(t)ide analogue therapy.

Emerging Diagnostic Tools to Decide When to Discontinue Nucleos(t)ide Analogues in Chronic Hepatitis B

The aim of this review is to outline emerging biomarkers that can serve as diagnostic tools to identify non-cirrhotic chronic hepatitis B (CHB) patients who could safely discontinue nucleos(t)ide analogues (NAs) before HBsAg loss. Regarding possible predictors of post-NAs outcomes, a number of studies have evaluated numerous factors, which can be categorised in markers of hepatitis B virus (HBV) activity, markers of host immune response and markers of other patient characteristics. In clinical practice, the most important question for patients who discontinue NAs is to differentiate those who will benefit by achieving HBsAg loss or at least by remaining in remission and those who will relapse requiring retreatment. Most of the discontinuation studies so far came from Asian and only few from European populations and examined the rates and predictors of post-NA virological and/or combined relapses or HBsAg loss. To date, there is still controversy about predictors of post-NA relapses, while only HBsAg serum levels at NA discontinuation seem to be the most robust predictive marker of the probability of subsequent off-treatment HBsAg seroclearance. Newer viral markers such as HBV RNA and hepatitis B core-related antigen seem promising, but further research is required.

Serum HBV pregenomic RNA is correlated with Th1/Th2 immunity in treatment-naïve chronic hepatitis B patients

BACKGROUND AND AIM

Hepatitis B virus (HBV) load and antigens are related to the innate and adaptive immunity of chronic hepatitis B (CHB) patients. As a new HBV biomarker, the role of pregenomic RNA (pgRNA) in host immunity is not known. This study aimed to identify the relationship between serum HBV pgRNA and host immunity in CHB patients.

METHODS

Two hundred twenty-five treatment-naïve CHB patients were enrolled. Serum cytokines were measured by cytokine antibody array (Luminex multiplex platform). Th1 (T-helper cell, Th) and Th2 cells were tested by flow cytometry. Serum HBV pgRNA was detected by a reverse transcription-polymerase chain reaction.

RESULTS

Serum HBV pgRNA was significantly different among patients in different disease phases and significantly associated with both HBV antigens and antibodies. Serum HBV pgRNA was positively correlated with the HBsAg level (P < .001) and the presence of HBeAg (P < .001). Patients with higher HBcAb levels showed lower serum HBV pgRNA levels (P = .003). Notably, HBsAb positivity was associated with higher levels of serum HBV pgRNA in HBeAg(-) patients (P = .049). Serum HBV pgRNA was positively associated with ALT level, Th2 cell frequency, and related cytokine sCD30 (P < .001, P < .001, and P = .003, respectively), but negatively associated with Th1-related cytokine interleukin (IL)-12P70 and cytotoxic lymphocytes (CTLs) (P = .017 and P < .001, respectively).

CONCLUSION

Our study confirmed the relationship between serum HBV pgRNA and host immunity. The results demonstrated that serum HBV pgRNA is positively correlated with Th2 immunity but negatively correlated with Th1 immunity, indicating that it might have a relationship with HBV antigen conversion and CTL immunodeficiency in CHB patients.

Pregenomic RNA: How to assist the management of chronic hepatitis B?

Pregenomic RNA (pgRNA) is an emerging serological marker for chronic hepatitis B virus (HBV) infection. While pgRNA is principally the template for viral proteins and viral DNAs, additional novel functions for the serum pgRNA have recently been described. These results extend for pgRNA a regulatory function in the viral life cycle and potentially a role in pathogenesis. Here, we review the diverse roles of pgRNA in HBV replication and pathogenesis, emphasizing how the unique structure of this RNA is key to its various functions. We focus in particular on the role of HBV pgRNA in guiding antiviral therapy including nucleot(s)ide analog interruption and role as a marker of cure with new curative therapies. We also briefly allude to the emerging niche for new direct-acting or indirect-acting antivirals targeting pgRNA.

Serum hepatitis B virus RNA levels as a predictor of HBeAg seroconversion during treatment with peginterferon alfa-2a

Background

Hepatitis B e antigen (HBeAg) seroconversion represents an endpoint of treatment of chronic hepatitis B virus (HBV) infections.

Methods

We have studied whether levels of serum hepatitis B virus ribonucleic acid (HBV RNA) during pegylated interferon alfa-2a treatment might be helpful for predicting HBeAg seroconversion. 61 HBeAg-positive chronic hepatitis B (CHB) patients treated with pegylated interferon alfa-2a alone or in combination with adefovir (10 mg/day) for 48 weeks were included in this retrospective analysis. Response was defined as HBeAg seroconversion at 24 weeks posttreatment. Receiver operating characteristic analyses were used to identify baseline and on-treatment HBV RNA levels associated with response.

Results

Twenty-two of 61 (36.1%) patients achieved a response. Baseline HBV RNA levels were lower in responders than in nonresponders (4.55 ± 1.19 and 5.90 ± 1.13 copies/mL, respectively, P = 0.001). Baseline HBV RNA cut off level (200,000 copies/mL) provided a positive predictive value (PPV) of 56.0% and a negative predictive value (NPV) of 77.8%. HBV RNA level (3000 copies/mL) at week 12 provide a PPV of 75.0% and a NPV of 82.8%. Moreover, HBeAg seroconversion rates at 24 weeks posttreatment were significantly higher in patients with HBV RNA ≤ 200,000 copies/mL at baseline and HBV RNA ≤ 3000 copies/mL at week 12 (92.9%) versus others (12.5%) (All P < 0.05).

Conclusions

In Conclusions, serum HBV RNA levels may serve as a novel tool for prediction of HBeAg seroconversion during therapy with pegylated interferon alfa-2a in HBeAg-positive CHB patients.

Electronic supplementary material

The online version of this article (10.1186/s12985-019-1152-6) contains supplementary material, which is available to authorized users.

Management of infected pancreatic necrosis in the setting of concomitant rectal cancer: A case report and review of literature

BACKGROUND

Pancreatitis with infected necrosis is a severe complication of acute pancreatitis and carries with it high rates of morbidity and mortality. The management of infected pancreatic necrosis alongside concomitant colorectal cancer has never been described in literature.

CASE SUMMARY

A 77 years old gentleman presented to the Emergency Department of our hospital complaining of ongoing abdominal pain for 8 h. The patient had clinical features of pancreatitis with a raised lipase of 3810 U/L, A computed tomography (CT) abdomen confirmed pancreatitis with extensive peri-pancreatic edema. During the course of his admission, the patient had persistent high fevers and delirium thought secondary to infected necrosis, prompting the commencement of broad-spectrum antibiotic therapy with Piperacillin/Tazobactam. Subsequent CT abdomen confirmed extensive pancreatic necrosis (over 70%). Patient was managed with supportive therapy, nutritional support and gut rest initially and improved over the course of his admission and was discharged 42 d post admission. He represented 24 d following his discharge with fever and chills and a repeat CT abdomen scan noted gas bubbles within the necrotic pancreatic tissue thereby confirming infected necrotic pancreatitis. This CT scan also revealed asymmetric thickening of the rectal wall suspicious for malignancy. A rectal cancer was confirmed on flexible sigmoidoscopy. The patient underwent two endoscopic necrosectomies and was treated with intravenous antibiotics and was discharged after 28 d. Within 1 wk post discharge, the patient commenced a course of neoadjuvant radiotherapy and subsequently underwent concomitant chemotherapy prior to undergoing a successful Hartmann’s procedure for treatment of his colorectal cancer.

CONCLUSION

This case highlights the efficacy of endoscopic necrosectomy, early enteral feeding and targeted antibiotic therapy for timely management of infected necrotic pancreatitis. The prompt resolution of pancreatitis permitted the patient to undergo neoadjuvant treatment and resection for his concomitant colorectal cancer.

Serum HBV RNA quantification: useful for monitoring natural history of chronic hepatitis B infection

BACKGROUND

As an alternative biomarker of intrahepatic covalently closed circular DNA (cccDNA) transcriptional activity, hepatitis B virus (HBV) RNA may evolve during long-lasting virus-host interactions during chronic hepatitis B viral infection. The distribution pattern of serum HBV RNA levels in the natural course of chronic HBV infection remains unclear. The aim of this study was to evaluate the levels of HBV RNA during the natural course of CHB and the role in distinguishing the natural history of HBV infection.

METHODS

A total of 291 treatment-naïve chronic HBV carriers were enrolled. Based on the clinical, biochemical, serological, and histological data as well as HBV DNA levels, patients were classified into the following four categories: the immune-tolerant phase (IT,n = 35), HBeAg-positive immune-active phase (EPIA,n = 121), inactive chronic hepatitis B(ICH,n = 77) and HBeAg-negative immune reactive hepatitis (ENH,n = 58) [corrected]. The parameters and distribution patterns of serum HBV RNA were evaluated in relation to viral replication status, immune phase, disease category and Child-Pugh class. The relationships between serum HBV RNA and other serum hepatitis B viral markers were also analyzed.

RESULTS

Serum HBV RNA levels were significantly lower in the HBeAg-negative patients compared to those in the HBeAg-positive patients, with the lowest levels seen in inactive carriers. In HBeAg-negative patients, serum HBV RNA levels increased if there is reactivation to active hepatitis and showed obvious superiority for the combination of serum HBV DNA (cutoff>3.39 Log copies/mL) and HBsAg (cutoff>2.74 Log IU/mL) in discriminating between 'HBeAg-negative immune reactive' phase and inactive chronic hepatitis B phases of HBeAg-negative chronic HBV infection. Serum HBV RNA levels were positively correlated with serum HBV DNA and HBsAg levels in all chronic HBV-infected patients. A stratified analysis revealed that a correlation between serum HBV RNA and HBV DNA or HBsAg was present in HBeAg-positive patients; however, in HBeAg-negative patients, serum HBV RNA was positively correlated with HBV DNA only.

CONCLUSION

During the natural course of chronic HBV infection, serum HBV RNA levels vary. Serum HBV RNA can act as a biomarker to predict the natural history of disease in chronic hepatitis B patients. In treatment-naïve HBeAg-negative chronic HBV-infected individuals, serum HBV RNA shows superiority in differentiating the 'HBeAg-negative reactive' phase.

Serum Hepatitis B Virus RNA: A New Potential Biomarker for Chronic Hepatitis B Virus Infection

Chronic hepatitis B infection is one of the major etiological causes of liver failure, cirrhosis, and hepatocellular carcinoma (HCC) worldwide. This condition cannot be completely cured by currently available drugs due to the persistent existence of hepatitis B virus (HBV) covalently closed circular DNA (cccDNA), the bona fide transcription template for HBV RNAs, in infected hepatocytes. Because quantifying cccDNA per se requires an invasive procedure, serum biomarkers reflecting intrahepatic cccDNA activity are warranted. Recently, a growing body of research suggests that the circulating HBV RNA may serve as a serum biomarker for HBV infection, treatment, and prognosis. In order to delineate the molecular and clinical characteristics of serum HBV RNA, we systematically reviewed the available literature on serum HBV RNA dating back to the early 1990s. In this review, we summarize the reported serum HBV RNA quantification methods and discuss the potential HBV RNA species in patient serum. We also compare the reported correlations of serum HBV RNA with other serological markers, including HBV DNA, hepatitis B surface antigen, e antigen, and core-related antigen, as well as their correlations with intrahepatic cccDNA, to assess their potential in clinical applications. Future directions for serum HBV RNA research are also discussed.

Serum hepatitis B virus RNA is a predictor of HBeAg seroconversion and virological response with entecavir treatment in chronic hepatitis B patients

BACKGROUND

Characteristics of alterations of serum hepatitis B virus (HBV) RNA in different chronic hepatitis B (CHB) patients still cannot be fully explained. Whether HBV RNA can predict HBeAg seroconversion is still controversial.

AIM

To investigate whether HBV RNA can predict virological response or HBeAg seroconversion during entecavir (ETV) treatment when HBV DNA is undetectable.

METHODS

The present study evaluated 61 individuals who were diagnosed and treated with long-term ETV monotherapy at the Department of Infectious Diseases of Peking University First Hospital (China) from September 2006 to December 2007. Finally, 30 treatment-naive individuals were included. Serum HBV RNA were extracted from 140 μL serum samples at two time points. Then they were reverse transcribed to cDNA with the HBV-specific primer. The product was quantified by real-time quantitative PCR (RT-PCR) using TAMARA probes. Statistical analyses were performed with IBM SPSS 20.0.

RESULTS

Level of serum HBV RNA at baseline was 4.15 ± 0.90 log₁₀ copies/mL. HBV RNA levels showed no significant difference between the virological response (VR) and partial VR (PVR) groups at baseline (P = 0.940). Serum HBV RNA significantly decreased among patients who achieved a VR during ETV therapy (P < 0.001). The levels of HBV RNA in both HBeAg-positive patients with seroconversion group and those with no seroconversion increased after 24 wk of treatment. Overall, HBV RNA significantly but mildly correlated to HBsAg (r = 0.265, P = 0.041), and HBV RNA was not correlated to HBV DNA (r = 0.242, P = 0.062). Furthermore, serum HBV RNA was an independent indicator for predicting HBeAg seroconversion and virological response. HBeAg seroconversion was more likely in CHB patients with HBV RNA levels below 4.12 log₁₀ copies/mL before treatment.

CONLUSION

The level of serum HBV RNA could predict HBeAg seroconversion and PVR during treatment. In the PVR group, the level of serum HBV RNA tends to be increasing.

Analysis of serum hepatitis B virus RNA levels in a multiethnic cohort of pregnant chronic hepatitis B carriers

BACKGROUND

Hepatitis B virus (HBV) flares have been reported due to alterations in the immune system during pregnancy. Recent studies in non-pregnant chronic hepatitis B (CHB) carriers have indicated that serum HBV RNA is a novel viral marker to assess treatment response and risk of disease flares.

OBJECTIVES

To analyze serum HBV RNA levels in association with established HBV markers in pregnant and/or post-partum CHB carriers.

STUDY DESIGN

In this prospective cohort study, serum and plasma were collected from 46 pregnant and/or post-partum CHB patients. Clinical data included demographics, hepatitis B e antigen (HBeAg) status (Abbott), quantitative hepatitis B s antigen (qHBsAg) levels (Abbott), HBV DNA (Abbott, sensitivity 10 IU/mL), alanine aminotransferase (ALT), liver stiffness measurement (LSM, post-partum), and treatment regime. Serum HBV total RNA and pre-genomic (pg)RNA were quantified using in-house assays, and HBV genotype was determined by direct population sequencing of HBV surface gene. Parametric and non-parametric statistical methods were used for analysis.

RESULTS

In this study, we found that serum HBV total RNA levels correlated with the HBeAg status, HBV DNA, qHBsAg, ALT, and LSM while serum HBV pgRNA levels did not (p < 0.05, N = 46). Additionally, HBV total RNA & pgRNA levels increased, HBV DNA levels decreased, and qHBsAg levels remained unchanged throughout tenofovir disoproxil fumarate (TDF) treatment (N = 2).

CONCLUSIONS

The associations between serum HBV total RNA with other validated markers indicates it may be a complementary HBV marker to monitor liver disease and HBV replication during pregnancy.

Hepatitis B Virus Serum DNA andRNA Levels in Nucleos(t)ide Analog-Treated or Untreated Patients During Chronic and Acute Infection

Treatment of chronic hepatitis B (CHB) patients with nucleos(t)ide analogs (NAs) suppresses hepatitis B virus (HBV) DNA synthesis but does not affect synthesis of HBV pregenomic RNA (pgRNA). Hepatitis B virus pgRNA is detectable in the serum during NA treatment and has been proposed as a marker of HBV covalently closed circular DNA activity within the infected hepatocyte. We developed an automated assay for the quantification of serum HBV pgRNA using a dual-target real-time quantitative PCR approach on the Abbott m2000sp/rt system. We demonstrate accurate detection and quantification of serum HBV RNA. Hepatitis B virus DNA was quantified using the Abbott RealTime HBV viral load assay. We further compared serum nucleic acid levels and kinetics in HBV-positive populations. Samples included on-therapy CHB samples (n = 16), samples (n = 89) from 10 treatment naïve CHB subjects receiving 12 weeks of NA treatment with 8-week follow-up, hepatitis B surface antigen-positive blood donor samples (n = 102), and three seroconversion series from plasmapheresis donors (n = 79 samples). Conclusion: During NA treatment of CHB subjects, we observed low correlation of HBV DNA to pgRNA levels; pgRNA concentration was generally higher than HBV DNA concentrations. In contrast, when NA treatment was absent we observed serum pgRNA at concentrations that correlated to HBV DNA and were approximately 2 log lower than HBV DNA. Importantly, we observe this trend in untreated subject samples from both chronic infections and throughout seroconversion during acute infection. Results demonstrate that the presence of pgRNA in serum is part of the HBV lifecycle; constant relative detection of pgRNA and HBV DNA in the serum is suggestive of a linked mechanism for egress for HBV DNA or pgRNA containing virions.

Clinical Implications of Hepatitis B Virus RNA and Covalently Closed Circular DNA in Monitoring Patients with Chronic Hepatitis B Today with a Gaze into the Future: The Field Is Unprepared for a Sterilizing Cure

. Chronic hepatitis B virus (HBV) infection has long remained a critical global health issue. Covalently closed circular DNA (cccDNA) is a persistent form of the HBV genome that maintains HBV chronicity. Decades of extensive research resulted in the two therapeutic options currently available: nucleot(s)ide analogs and interferon (IFN) therapy. A plethora of reliable markers to monitor HBV patients has been established, including the recently discovered encapsidated pregenomic RNA in serum, which can be used to determine treatment end-points and to predict the susceptibility of patients to IFN. Additionally, HBV RNA splice variants and cccDNA and its epigenetic modifications are associated with the clinical course and risks of hepatocellular carcinoma (HCC) and liver fibrosis. However, new antivirals, including CRISPR/Cas9, APOBEC-mediated degradation of cccDNA, and T-cell therapies aim at completely eliminating HBV, and it is clear that the diagnostic arsenal for defining the long-awaited sterilizing cure is missing. In this review, we discuss the currently available tools for detecting and measuring HBV RNAs and cccDNA, as well as the state-of-the-art in clinical implications of these markers, and debate needs and goals within the context of the sterilizing cure that is soon to come.

Hepatitis B virus: The challenge of an ancient virus with multiple faces and a remarkable replication strategy

The hepatitis B virus (HBV) is the prototype member of the Hepadnaviridae, an ancient family of hepatotropic DNA viruses, which may have originated from 360 to 430 million years ago and with evidence of endogenization in reptilian genomes >200 million years ago. The virus is currently estimated to infect more than 250 million humans. The extremely successful spread of this pathogen among the human population is explained by its multiple particulate forms, effective transmission strategies (particularly perinatal transmission), long induction period and low associated mortality. These characteristics confer selective advantages, enabling the virus to persist in small, disperse populations and spread worldwide, with high prevalence rates in many countries. The HBV replication strategy is remarkably complex and includes a multiplicity of particulate structures. In addition to the common virions containing DNA in a relaxed circular (rcDNA) or double-stranded linear (dslDNA) forms, the viral population includes virion-like particles containing RNA or "empty" (viral envelopes and capsids without genomes), subviral particles (only an envelope) and even naked capsids. Consequently, several forms of the genome coexist in a single infection: (i) the "traveler" forms found in serum, including rcDNA and dslDNA, which originate from retrotranscription of a messenger RNA (the pregenomic RNA, another form of the viral genome itself) and (ii) forms confined to the host cell nucleus, including covalently closed circular DNA (cccDNA), which leads to a minichromosome form associated with histones and viral proteins, and double-stranded DNA integrated into the host genome. This complex composition lends HBV a kind of "multiple personality". Are these additional particles and genomic forms simple intermediaries/artifacts or do they play a role in the viral life cycle?