As new evidence emerges, treatment strategies toward the functional cure of chronic hepatitis B are evolving. In 2019, a panel of national hepatologists published a Consensus Statement on the functional cure of chronic hepatitis B. Currently, an international group of hepatologists has been assembled to evaluate research since the publication of the original consensus, and to collaboratively develop the updated statements. The 2.0 Consensus was aimed to update the original consensus with the latest available studies, and provide a comprehensive overview of the current relevant scientific literatures regarding functional cure of hepatitis B, with a particular focus on issues that are not yet fully clarified. These cover the definition of functional cure of hepatitis B, its mechanisms and barriers, the effective strategies and treatment roadmap to achieve this endpoint, in particular new surrogate biomarkers used to measure efficacy or to predict response, and the appropriate approach to pursuing a functional cure in special populations, the development of emerging antivirals and immunomodulators with potential for curing hepatitis B. The statements are primarily intended to offer international guidance for clinicians in their practice to enhance the functional cure rate of chronic hepatitis B.

As new evidence emerges, treatment strategies toward the functional cure of chronic hepatitis B are evolving. In 2019, a panel of national hepatologists published a Consensus Statement on the functional cure of chronic hepatitis B. Currently, an international group of hepatologists has been assembled to evaluate research since the publication of the original consensus, and to collaboratively develop the updated statements. The 2.0 Consensus was aimed to update the original consensus with the latest available studies, and provide a comprehensive overview of the current relevant scientific literatures regarding functional cure of hepatitis B, with a particular focus on issues that are not yet fully clarified. These cover the definition of functional cure of hepatitis B, its mechanisms and barriers, the effective strategies and treatment roadmap to achieve this endpoint, in particular new surrogate biomarkers used to measure efficacy or to predict response, and the appropriate approach to pursuing a functional cure in special populations, the development of emerging antivirals and immunomodulators with potential for curing hepatitis B. The statements are primarily intended to offer international guidance for clinicians in their practice to enhance the functional cure rate of chronic hepatitis B.

As new evidence emerges, treatment strategies toward the functional cure of chronic hepatitis B are evolving. In 2019, a panel of national hepatologists published a Consensus Statement on the functional cure of chronic hepatitis B. Currently, an international group of hepatologists has been assembled to evaluate research since the publication of the original consensus, and to collaboratively develop the updated statements. The 2.0 Consensus was aimed to update the original consensus with the latest available studies, and provide a comprehensive overview of the current relevant scientific literatures regarding functional cure of hepatitis B, with a particular focus on issues that are not yet fully clarified. These cover the definition of functional cure of hepatitis B, its mechanisms and barriers, the effective strategies and treatment roadmap to achieve this endpoint, in particular new surrogate biomarkers used to measure efficacy or to predict response, and the appropriate approach to pursuing a functional cure in special populations, the development of emerging antivirals and immunomodulators with potential for curing hepatitis B. The statements are primarily intended to offer international guidance for clinicians in their practice to enhance the functional cure rate of chronic hepatitis B.

Chronic hepatitis B virus (HBV) infection is one of the major public health issues of ongoing global concern. Due to inadequate understanding of the HBV life cycle, there is a lack of effective drugs to cure chronic hepatitis B. During HBV replication, covalently closed circular DNA (cccDNA) serves as the template for viral replication and can be transcribed to produce five viral RNAs of 3.5, 2.4, 2.1 kb and 0.7 kb in length, which are translated to produce HBeAg, core protein, polymerase (P) protein, HBsAg and HBx proteins, respectively. Among them, the 3.5 kb pregenomic RNA (pgRNA) is also the template for viral reverse transcription. Polymerase protein recognizes and binds to the capsid assembly signal on the pgRNA to initiate capsid assembly and reverse transcription. Recent studies have revealed that the processes of splicing, nuclear export, stability, translation, and pgRNA encapsidation of HBV RNAs are regulated by a post-transcriptional regulatory network within the host cell and depend on unique post-transcriptional regulatory elements in the HBV RNA structure. The aim of this review is to overview the post-transcriptional regulatory mechanisms of HBV RNA and their applications in the study of HBV antiviral therapeutics, with the aim of providing new ideas for the development of new drugs targeting HBV RNA.

Chronic hepatitis B virus (HBV) infection is the main etiology of viral hepatitis, cirrhosis, and primary hepatocellular carcinoma and is also a major public health problem worldwide. With the progression of chronic infection, HBV DNA continuously integrates into host DNA and brings about integration and insertion mutations within host genes. In the process of repeated chronic inflammatory necrosis and compensatory regeneration, hepatocytes carrying HBV DNA integration have an advantage in proliferation and frequent clonal expansion formation that causes the accumulation of mutations over time and ultimately malignant transformation of hepatocytes. Although nucleos(t)ide analogs (NAs), currently the most widely used, can effectively inhibit viral replication, delay disease progression in patients with chronic hepatitis B, and significantly reduce the occurrence of end-stage liver disease, many patients still progress to liver cancer. Furthermore, even among clinically cured patients with hepatitis B surface antigen clearance, NAs have not significantly reduced the long-term occurrence of liver cancer, suggesting that their impact under previous treatment strategies for reducing the risk of liver cancer is limited. This could be due to antiviral treatment initiation at a time when patients already have numerous integrated cell proliferation colonies. Hence, NAs have not had any therapeutic impact on the expression of integrated HBV DNA fragments and viral proteins, such as hepatitis B surface antigen. In light of this, we suggest initiating antiviral treatment as early as possible to pursue clinical cure and ultimately reduce the risk of liver cancer in patients with chronic HBV infection.

Chronic hepatitis B virus(HBV)infection is the major cause of chronic hepatitis B(CHB),liver cirrhosis,and primary hepatocellular carcinoma(HCC)and brings huge health and economic burdens to the society.The disease progression of CHB is driven by the interaction between the virus,host immune response,and infected hepatocytes.Staging of the natural history of chronic HBV infection will help to understand disease progression,assess the stage of disease progression,and provide guidance for determining the time and regimen of antiviral therapy.Due to the controversy over the existence of a true immune tolerance phase,Guidelines for the prevention and treatment of chronic hepatitis B(2022 edition)in China weakens the association between disease state and host immune status and provides an updated description of the natural history of chronic HBV infection based on the four disease stages from the 2017 European Association for the Study of the Liver(EASL)guidelines,i.e.,HBeAg-positive chronic HBV infection,HBeAg-positive CHB,HBeAg-negative chronic HBV infection,and HBeAg-negative CHB.Moreover,it fails to fully resolve the issue of the"indeterminate phase".With the growing trend of expanding antiviral treatment strategies in clinical practice,the current staging system based on natural history can hardly meet clinical needs,and thus it is necessary to make updates.This article elaborates on the discovery of the natural history of chronic HBV infection,the problems of the existing staging system of natural history,and related recommendations,in order to simplify the staging system of natural history,align with current antiviral treatment regimens,and facilitate clinical decision-making by clinicians.

ObjectiveThe natural history of chronic HBV infection often involves a histologically defined immune tolerance state， and once such immune tolerance state is broken， antiviral therapy should be initiated immediately. This study aims to investigate the correlation between immune-mediated liver injury and virological indicators for HBV and precisely identify the patients with a histologically defined immune tolerance state. MethodsThis study was conducted among 577 HBeAg-positive chronic hepatitis B （CHB） patients with HBV DNA >2×10⁶ IU/mL who did not receive antiviral therapy in The Fifth Medical Center of PLA General Hospital， Tianjin Second People’s Hospital， Shanghai Ruijin Hospital， and Taizhou Hospital of Zhejiang Province from January 2010 to December 2022. Liver biopsy was performed to determine the extent of liver injury， and the serum levels of alanine aminotransferase （ALT）， aspartate aminotransferase （AST）， and virological indicators were measured. The proportion of patients with a histologically defined immune tolerance state was analyzed based on the cut-off values of noninvasive indicators recommended in various guidelines， especially HBV load. In addition， a diagnostic model was established for the histologically defined immune tolerance state based on serum HBV DNA at the time when its correlation with liver immunopathological injury disappeared as the new threshold in combination with multiple indicators. The Mann-Whitney U test was used for comparison of continuous data between two groups， and the chi-square test was used for comparison of categorical data between two groups. The Spearman method was used for correlation analysis. The binary Logistic regression analysis was used to establish a multivariate diagnostic model； the area under the receiver operating characteristic curve （AUC） was used to investigate the diagnostic efficiency of different models， and the Z test was used for comparison of AUC. ResultsAmong the patients with an immune tolerance state defined by the noninvasive indicators in the Chinese guidelines （2022 edition）， the EASL guidelines （2017 edition）， the AASLD guidelines （2018 edition）， and the APASL guidelines （2015 edition） for the prevention and treatment of CHB， the patients with a histologically defined immune tolerance state who met the definition in this article （HBV DNA>2×10⁶ IU/mL） accounted for 47.0%， 38.5%， 36.0%， and 44.6%， respectively， which did not exceed 50%. When the threshold of serum HBV DNA increased to >2×10⁸ IU/mL， although the correlation between immune-mediated liver injury and HBV DNA disappeared （r=-0.029， P=0.704）， the patients with a histologically defined immune tolerance state reached only 52.0%. In the cohort of 251 HBeAg-positive patients with serum HBV DNA >1×10⁸ IU/mL， there were significant differences in the levels of HBsAg， HBeAg， HBV DNA， ALT， and AST between the significant liver injury group with 140 children and the non-significant liver injury group with 111 patients （all P<0.05）， and the multivariate binary Logistic regression analysis showed that AST， HBV DNA， and HBeAg were influencing factors for histologically defined immune tolerance state in patients （all P<0.05）. Based on the above indicators and related clinical data， a predictive model was established as logit（P）=1.424－0.028×AST， with an AUC of 0.730， an optimal cut-off value of 30.5 U/L， a sensitivity of 52.8%， and a specificity of 84.1%. A total of 238 adult patients with chronic HBV infection who underwent liver biopsy in Taizhou Hospital of Zhejiang Province were enrolled as the validation cohort， and the analysis showed that the predictive model established in this study had a better efficiency than AST/ALT， FIB-4， and APRI， with an AUC of 0.698， 0.555， 0.518， and 0.373， respectively （all P<0.05）. ConclusionFor HBeAg-positive patients with chronic HBV infection and HBV DNA>2×10⁸ IU/mL， an AST level of >30.5 U/L might indicate the “breakdown” of histologically defined immune tolerance state.

Cell-free DNA (cfDNA) is the DNA fragment existing in human extracellular fluid. In specific physiological process (such as pregnancy) or pathological conditions (such as human malignancies), the contents of cfDNA in extracellular fluid will abnormally change. The contents and molecular characteristics of cfDNA make it have the potential as a kind of biomarker for diseases′ diagnosis. With the development of cfDNA detection technology such as sequencing and mass spectrometry, liquid biopsy based on cfDNA detection has been widely used in clinical tumor diagnosis, tumor treatment, prenatal examination, and research in autoimmune diseases. A systematic summary of the latest research progress in the development of cfDNA detection technology and the clinical application of liquid biopsy, as well as the research progress of cfDNA in the diagnosis and treatment of related diseases is summarized in this review.

Recently, several phase I and phase II clinical trials of antisense oligodeoxynucleotides (ASOs) targeting to the commonly shared conserved sequences of HBV transcripts brought us some promising results. Particularly in the report of phase IIb clinical trial of Bepirovirsen (GSK3228836), approximately 9-10% patients with low baseline serum HBsAg (> 100 IU/ml & < 3 000 IU/ml) achieved functional cure after 24 weeks’ of Bepirovirsen treatment. After reviewing the results of other clinical trials, one would be impressed to know that ALG-020572 (Aligos), RO7062931 (Roche) and GSK3389404 (GSK) all failed to sufficiently suppress serum HBsAg expression though the hepatocyte-targeted delivery of these ASOs were enhanced via N-acetyl galactosamine conjugation. Bepirovirsen enabled some patients to achieve sustained disappearance of serum HBsAg. The analysis of its distribution in different tissues of patients after drug administration showed that only a few fractions of ASOs entered liver tissues and far fewer eventually entered hepatocytes. Taking into consideration that only a few hepatocytes could be expected positive for HBsAg staining among these participants with low serum HBsAg level. We suspect that the mechanistic contribution of ASOs declining the serum HBsAg is not only via directly acting on the HBV transcripts in hepatocytes, but also via entering non-parenchymal cells such as Kupffer cells and resulting in stimulation and activation of innate immunity. Eventually the serum HBsAg declines in most participants and even disappears in a small fraction of patients with low baseline HBsAg level, via attack the infected hepatocytes evidenced by the aberrant elevation of ALT. Nevertheless, the functional cure of CHB remains a challenging issue and more efforts are needed.

Objective:To explore the relationship and dynamic changes between virological markers and hepatic pathological damage due to host anti-hepatitis B virus (HBV) immunity in the natural course of disease in chronic HBV infected patients.Methods:Two hundred and thirty-eight adult chronic HBV-infected patients who underwent liver biopsy from January 2016 to June 2022 in Taizhou Hospital, Zhejiang Province, were retrospectively selected. General clinical data such as age, gender, platelets, ALT, AST, albumin, HBV DNA, qHBsAg, HBeAg, and liver pathology diagnostic indexes such as the grade of liver necroinflammation and liver fibrotic stages of the patients were collected. The patients were grouped according to HBeAg status, and subgrouped according to different grades of liver necroinflammation and different HBV DNA loads. Statistical analyses were performed to compare the differences in HBV virologic marker levels between the groups, and the correlation between them and the indicators of hepatic inflammatory injury, such as ALT,AST, and the grade of liver necroinflammation in the patients.Results:The levels of HBV virological markers in HBeAg-positive patients with moderate or higher liver necroinflammatory grade (G≥2) were significantly lower than those with mild (no) liver necroinflammatory grade (G < 2) ( P < 0.01); whereas the opposite trend was observed in HBeAg-negative patients, with the levels of HBV DNA, and qHBsAg in the G≥2 subgroup being significantly higher than those in the G < 2 subgroup ( P < 0.01). Correspondingly, HBV DNA level and qHBsAg showed weak to moderately strong negative correlation with liver necroinflammatory grade and AST which was an indicator of hepatic inflammatory injury in HBeAg-positive patients ( P < 0.05); whereas in HBeAg-negative patients, they showed weak to moderately strong positive correlation with hepatic inflammatory activity and ALT, AST ( P < 0.001), in which qHBsAg showed only a weak positive correlation with patients' liver necroinflammatory grade ( P = 0.003). Further subgroup analyses of HBeAg-positive patients according to whether the HBV DNA level was > 2×10 6 IU/ml showed weak to moderate negative correlations between HBV virological markers and liver necroinflammatory grade as well as ALT and AST in the subgroup of patients with HBV DNA > 2×10 6 IU/ml ( P < 0.05); however, the negative correlation disappeared in patients who were still HBeAg positive and had HBV DNA ≤ 2×10 6 IU/ml. Moreover, HBV DNA and ALT, HBeAg and AST showed moderate positive correlation ( P < 0.05). Conclusion:We speculate that the activation of host anti-HBV immunity can efficiently inhibit HBV replication by targeting the infected hepatocytes, but only in the early phase of disease progression in HBeAg positive patients with HBV DNA high (> 2×10 6 IU/ml).