Association of serum hepatitis B virus RNA with hepatocellular carcinoma risk in chronic hepatitis B patients under nucleos(t)ide analogues therapy

Biogenesis of serum HBV RNA and clinical phenomena of serum HBV RNA in chronic hepatitis B patients before and after receiving nucleos(t)ide analogues therapy

There are estimated 300 million people afflicted with chronic hepatitis B (CHB) worldwide. The risk of liver cirrhosis and hepatocellular carcinoma (HCC) increases considerably with chronic hepatitis B infection. While current therapeutics are effective in controlling hepatitis B virus (HBV) infection and disease progression, a cure for HBV infection remains unattainable due to an intranuclear replicative intermediate known as covalently closed circular DNA (cccDNA). It has recently been shown that serum HBV RNA is a non-invasive biomarker that reflects cccDNA transcriptional activity. This review provides a comprehensive overview and the latest updates on the molecular characteristics and clinical significance of serum HBV RNA, such as species of serum HBV RNA, forms of serum HBV RNA carriers and predictive value for relapses in CHB patients after nucleos(t)ide analogues (NAs) discontinuation and development of liver fibrosis and HCC. Furthermore, we summarize standardized assays for testing serum HBV RNA, the dynamic changes of serum HBV RNA levels in treatment-naïve CHB patients and those under NAs therapy, as well as the host and viral influencing factors of serum HBV RNA levels. Finally, we discuss the future perspectives in studies of serum HBV RNA.

Hepatitis B surface antigen glycan isomer is a predictor of the development of hepatocellular carcinoma during nucleoside/nucleotide analog therapy

AIM

A recombinant monoclonal antibody against the hepatitis B surface antigen glycan isomer (HBsAgGi) was newly developed using the O-glycosylated PreS2 peptide in M-HBsAg of hepatitis B virus (HBV) genotype C. However, the association between HBsAgGi and the development of hepatocellular carcinoma (HCC) during nucleoside/nucleotide analog (NA) therapy remains unknown.

METHODS

A total of 112 HBV genotype C-infected patients who were treated with NA were included in this study. We assessed the association between HBV markers, including HBsAgGi and other conventional markers, and the development of HCC during NA therapy.

RESULTS

Ten patients developed HCC during the follow-up period. Of the HBV markers, HBsAg (≤3.53 log IU/mL; p = 0.047), HBsAgGi/HBsAg ratio (≥1.10; p = 0.035), and HBV DNA (≤6.3 log copies/mL; p = 0.012) at baseline and HBsAg (≤3.19 log IU/mL; p = 0.033) and HBsAgGi/HBsAg ratio (≥1.09; p = 0.003) at 48 weeks after NA therapy were significantly associated with the development of HCC according to the log rank test. In contrast, no significant association was observed between HBsAgGi and the development of HCC. Multivariate analysis revealed that a platelet count at baseline ≤88 × 103 /mm3 (p = 0.026; hazard ratio [HR], 10.577) and an HBsAgGi/HBsAg ratio at 48 weeks after NA therapy ≥1.09 (p = 0.040; HR, 10.099) were independently and significantly associated with the development of HCC.

CONCLUSIONS

Our findings suggest that a combination of on-treatment HBsAgGi and HBsAg predicts the development of HCC during NA therapy.

Interferon therapy improves survival in patients with hepatitis B virus-related hepatocellular carcinoma after curative surgery: a meta-analysis

BACKGROUND AND AIM

A novel study found interferon enhanced antitumor activity of anti-PD-1-based immunotherapy and played a crucial role in improving efficacy on HCC, but the opposite results about the efficacy of interferon on HBV-related HCC were obtained from previous clinical studies and meta-analyses. Thus, this meta-analysis aimed to re-evaluate whether interferon could improve survival and reduce recurrence of patients with HBV-related HCC after curative surgery.

METHODS

MEDLINE/PubMed, Cochrane Library, EMBASE, Web of Science and CNKI were searched for eligible studies from inception to November 2022 and a meta-analysis was done.

RESULTS

10 trials with a total of 2062 subjects were screened. Interferon significantly improved 1-, 2-, 3- and 5-year OS and 1-, 2- and 3-year DFS, and reduced 2-, 3- and 5-year recurrence rates of patients with HBV-related HCC after curative surgery. However, interferon did not improve 8-year OS and 5-year DFS, did not reduce 1-year recurrence rate.

CONCLUSIONS

Interferon may significantly reduce recurrence and improve DFS of patients with HBV-related HCC after curative surgery, and finally improve the OS. However, the efficacy advantage may gradually weaken as time goes on. The clinical application of interferon combined with NAs recommended in this meta-analysis is needed to be further studied.

Serum hepatitis B virus spliced RNA proportion increases with liver disease progression in patients with chronic hepatitis B

Serum hepatitis B virus (HBV) spliced RNAs (spRNAs) are ubiquitous in HBV-infected patients; however, their clinical significance remains unknown. Therefore, we aimed to explore the relationship between HBV spRNAs and liver disease progression in chronic hepatitis B (CHB) patients; in vitro cell line assessment was also performed. The serum HBV wild-type RNA (wtRNA) and spRNA levels were individually quantified in a cohort of 279 treatment-naïve, hepatitis B e antigen positive CHB patients with or without cirrhosis. The spRNA proportion was determined as (spRNA × 100%)/(spRNAs + wtRNA). 20 patients' serum samples underwent spRNA species profiling using next-generation sequencing. Serum spRNA species 1, 2, 3, 4, and 5 were the most common variants. The spRNA proportion varied from 0.00% to 19.02%, with higher levels in HBV genotype C patients than in those with genotype B (1.76% vs. 0.84%, p < 0.001). The spRNA proportion was positively associated with the alanine aminotransferase levels (r = 0.144, p = 0.053) and significantly higher in cirrhotic than in non-cirrhotic patients (1.69% vs. 1.04%, p = 0.001). Multivariate analysis revealed a 2.566-fold higher risk of cirrhosis in patients with elevated spRNA proportion (p = 0.024). In vitro experiments confirmed that spRNAs contributed to hepatic stellate cell activation, which is critical in liver fibrosis development. Therefore, increased HBV spRNA expression poses a risk for liver disease progression. Quantifying serum HBV spRNAs can aid in monitoring liver disease progression. Furthermore, the therapeutic targeting of spRNAs may improve the prognosis of patients with CHB.

Lower risk of hepatocellular carcinoma with tenofovir than entecavir in antiviral treatment-naïve chronic hepatitis B patients: a systematic review and meta-analysis involving 90,897 participants

Entecavir (ETV) and tenofovir disoproxil fumarate (TDF) are equally recommended as first-line treatments for antiviral treatment-naïve (ART-naïve) chronic hepatitis B (CHB) patients by practice guidelines because of their similarly high antiviral efficacy and low resistance rate. However, whether one is superior to the other in terms of hepatocellular carcinoma (HCC) prevention is currently largely controversial. We aimed to identify and synthesize these existing studies regarding the HCC risk of these two highly potent antivirals in treatment-naïve CHB patients. PubMed, EMBASE, and Cochrane Library were searched for studies between January 1, 2012 and June 25, 2022. These studies used ETV monotherapy and/or TDF monotherapy to treat ART-naïve CHB patients and reported the incidence of HCC. The extracted data were analyzed using a DerSimonian-Laird random-effects models. The HCC incidence difference was expressed as hazard ratio (HR) and 95% confidence interval (95% CI). A total of 17 studies with 90,897 ART-naïve CHB patients (ETV = 60,980 vs TDF = 29,917) were included in this meta-analysis. Compared with ETV, TDF was associated with a significant lower cumulative incidence of HCC (HR 0.66; 95% CI 0.56-0.76). No significant heterogeneity or publication bias was found among the included studies (I2 = 48.1%, Begg's p = 0.363 and Egger's p = 0.748). TDF is associated with a lower risk of HCC compared with entecavir in ART-naïve CHB patients. The results suggest that TDF may be a better option for ART-naïve CHB patients with high HCC risks.

Current and novel modalities for management of chronic hepatitis B infection

Over 296 million people are estimated to have chronic hepatitis B viral infection (CHB), and it poses unique challenges for elimination. CHB is the result of hepatitis B virus (HBV)-specific immune tolerance and the presence of covalently closed circular DNA as mini chromosome inside the nucleus and the integrated HBV. Serum hepatitis B core-related antigen is the best surrogate marker for intrahepatic covalently closed circular DNA. Functional HBV “cure” is the durable loss of hepatitis B surface antigen (HBsAg), with or without HBsAg seroconversion and undetectable serum HBV DNA after completing a course of treatment. The currently approved therapies are nucleos(t)ide analogues, interferon-alpha, and pegylated-interferon. With these therapies, functional cure can be achieved in < 10% of CHB patients. Any variation to HBV or the host immune system that disrupts the interaction between them can lead to reactivation of HBV. Novel therapies may allow efficient control of CHB. They include direct acting antivirals and immunomodulators. Reduction of the viral antigen load is a crucial factor for success of immune-based therapies. Immunomodulatory therapy may lead to modulation of the host immune system. It may enhance/restore innate immunity against HBV (as toll-like-receptors and cytosolic retinoic acid inducible gene I agonist). Others may induce adaptive immunity as checkpoint inhibitors, therapeutic HBV vaccines including protein (HBsAg/preS and hepatitis B core antigen), monoclonal or bispecific antibodies and genetically engineered T cells to generate chimeric antigen receptor-T or T-cell receptor-T cells and HBV-specific T cells to restore T cell function to efficiently clear HBV. Combined therapy may successfully overcome immune tolerance and lead to HBV control and cure. Immunotherapeutic approaches carry the risk of overshooting immune responses causing uncontrolled liver damage. The safety of any new curative therapies should be measured in relation to the excellent safety of currently approved nucleos(t)ide analogues. Development of novel antiviral and immune modulatory therapies should be associated with new diagnostic assays used to evaluate the effectiveness or to predict response.

Inverse Propensity Score-Weighted Analysis of Entecavir and Tenofovir Disoproxil Fumarate in Patients with Chronic Hepatitis B: A Large-Scale Multicenter Study

Tenofovir disoproxil fumarate (TDF) is reportedly superior or at least comparable to entecavir (ETV) in preventing hepatocellular carcinoma (HCC) among chronic hepatitis B (CHB) patients; however, it remains controversial. This study aimed to conduct comprehensive comparisons between the two antivirals. CHB patients initially treated with ETV or TDF between 2012 and 2015 at 20 referral centers in Korea were included. The primary outcome was the cumulative incidence of HCC. The secondary outcomes included death or liver transplantation, liver-related outcome, extrahepatic malignancy, development of cirrhosis, decompensation events, complete virologic response (CVR), seroconversion rate, and safety. Baseline characteristics were balanced using the inverse probability of treatment weighting (IPTW). Overall, 4210 patients were enrolled: 1019 received ETV and 3191 received TDF. During the median follow-ups of 5.6 and 5.5 years, 86 and 232 cases of HCC were confirmed in the ETV and TDF groups, respectively. There was no difference in HCC incidence between the groups both before (p = 0.36) and after IPTW was applied (p = 0.81). Although the incidence of extrahepatic malignancy was significantly higher in the ETV group than in the TDF group before weighting (p = 0.02), no difference was confirmed after IPTW (p = 0.29). The cumulative incidence rates of death or liver transplantation, liver-related outcome, new cirrhosis development, and decompensation events were also comparable in the crude population (p = 0.24-0.91) and in the IPTW-adjusted population (p = 0.39-0.80). Both groups exhibited similar rates of CVR (ETV vs. TDF: 95.1% vs. 95.8%, p = 0.38), and negative conversion of hepatitis B e antigen (41.6% vs. 37.2%, p = 0.09) or surface antigen (2.8% vs. 1.9%, p = 0.10). Compared to the ETV group, more patients in the TDF group changed initial antivirals due to side effects, including decreased kidney function (n = 17), hypophosphatemia (n = 20), and osteoporosis (n = 18). In this large-scale multicenter study, ETV and TDF demonstrated comparable effectiveness across a broad range of outcomes in patients with treatment-naïve CHB during similar follow-up periods.

Characterization of a Novel Capsid Assembly Modulator for the Treatment of Chronic Hepatitis B Virus Infection

The standard of care for the treatment of chronic hepatitis B (CHB) is typically lifelong treatment with nucleos(t)ide analogs (NAs), which suppress viral replication and provide long-term clinical benefits. However, infectious virus can still be detected in patients who are virally suppressed on NA therapy, which may contribute to the failure of these agents to cure most CHB patients. Accordingly, new antiviral treatment options are being developed to enhance the suppression of hepatitis B virus (HBV) replication in combination with NAs ("antiviral intensification"). Here, we describe GS-SBA-1, a capsid assembly modulator (CAM) belonging to class CAM-E, that demonstrates potent inhibition of extracellular HBV DNA in vitro (EC₅₀ [50% effective concentration] = 19 nM) in HBV-infected primary human hepatocytes (PHHs) as well as in vivo in an HBV-infected immunodeficient mouse model. GS-SBA-1 has comparable activities across HBV genotypes and nucleos(t)ide-resistant mutants in HBV-infected PHHs. In addition, GS-SBA-1 demonstrated in vitro additivity in combination with tenofovir alafenamide (TAF). The administration of GS-SBA-1 to PHHs at the time of infection prevents covalently closed circular DNA (cccDNA) formation and, hence, decreases HBV RNA and antigen levels (EC₅₀ = 80 to 200 nM). Furthermore, GS-SBA-1 prevents the production of extracellular HBV RNA-containing viral particles in vitro. Collectively, these data demonstrate that GS-SBA-1 is a potent CAM that has the potential to enhance viral suppression in combination with an NA.

Review article: novel biomarkers in hepatitis B infection

BACKGROUND

Chronic hepatitis B remains a global health problem with an estimated 296 million people affected worldwide. Individuals are at risk of serious complications such as cirrhosis and hepatocellular carcinoma and accurately predicting these clinical endpoints has proven difficult. However, several viral biomarkers have recently been developed, including quantitative HBV surface antigen (qHBsAg), hepatitis B RNA (HBV RNA) and core-related antigen (HBcrAg), and shown promise in a range of clinical settings.

AIMS

To critically appraise these novel biomarkers, exploring their potential uses, availability of assays and areas for future development.

METHODS

We performed a literature search of PubMed, identifying articles published in the field of hepatitis B biomarkers between 2010 and 2022.

RESULTS

Novel biomarkers such as HBcrAg, HBV RNA and qHBsAg may be useful in predicting treatment outcomes, stratifying the risk of future complications and estimating off-treatment viral reactivation. Furthermore, HBV RNA and HBcrAg titres may accurately reflect cccDNA transcriptional activity, and this is particularly informative in the context of nucleoside analogue therapy. On a cautionary note, most studies have been performed in Caucasian or Asian populations, and methods for detecting HBV RNA lack standardisation.

CONCLUSION

Novel viral biomarkers have the potential to provide additional insights into the natural history of infection and allow a more bespoke, cost-effective framework of care. However, access remains limited, and further efforts are needed to validate their use in ethnically diverse populations, confirm predictive cut-off values, and establish their role in the era of novel antiviral therapies.