Current Trend in Antiviral Therapy for Chronic Hepatitis B

Expression Pattern of Cytokines in Patients with Chronic Hepatitis B Receiving PEGinterferon Therapy

Purpose

Chronic hepatitis B virus (CHB) infection is a worldwide health problem. Polyethylene glycol (PEG)ylated interferon (PEG-IFN) is an available therapy for CHB that has antiviral and immunomodulatory effects. However, PEG-IFN therapy is limited by the fact that only a subset of patients show a sustained response, its severe side effects, and high cost. The aim of this study was to explore novel biomarkers for the early prediction of PEG-IFN treatment response and to uncover its underlying mechanism.

Patients and Methods

We enrolled 10 paired patients with Hepatitis B e antigen (HBeAg)-positive CHB who received PEG-IFN-α2a monotherapy. Patient serum samples were collected at 0, 4, 12, 24, and 48 weeks and serum samples were collected from eight healthy people as healthy controls. For confirmation, we enrolled 27 patients with HBeAg-positive CHB receiving PEG-IFN therapy and serum samples at 0 and 12 weeks were obtained. Serum samples were analyzed using Luminex technology.

Results

Among 27 assessed cytokines, 10 cytokines were identified to have high expression levels. Among them, six cytokines had significant differences in their levels between the patients with HBeAg-positive CHB and the healthy controls (P < 0.05). Potentially, treatment response could be predicted using the early time points of 4, 12, and 24 weeks. Moreover, after 12 weeks of PEG-IFN treatment, increased levels of pro-inflammatory cytokines and decreased levels of anti-inflammatory cytokines were observed. The fold change of IP-10 between 12 weeks and 0 weeks correlated with the decrease in ALT levels from 0 to 12 weeks (r = 0.2675, P = 0.0024).

Conclusion

In patients with CHB, we observed a certain pattern in the levels of cytokines during treatment with PEG-IFN, and the cytokine IP-10 might be a potential biomarker for treatment response.

Secular Trends of Clinical Characteristics and Survival of Hepatocellular Carcinoma in Taiwan from 2011 to 2019

Hepatocellular carcinoma (HCC) is a major cause of cancer death in Taiwan, and in the past 30-40 years, Taiwan has been committed to its prevention and treatment. We aimed to investigate the secular trends of characteristics and the survival of HCC in recent decades after making increased efforts. Between 2011 and 2019, a total of 73,817 cases were enrolled from the TCR database. The overall male-to-female ratio was 7/3. The overall, male and female mean ages increased from 63.8 to 66.1 years, 62.0 to 64.3 years and 68.3 to 70.4 years, respectively. After dividing by viral etiologies and gender, the mean age showed increasing trends in all subgroups. The proportions of HBV-HCC, HCV-HCC, HBV+HCV-HCC and Non-HBV+non-HCV-HCC were 48.3%, 25.2%, 5.3% and 21.3% in males, compared with 25.5%, 48.6%, 5.3% and 20.5% in females, respectively. The 5-year survival rates of BCLC stages 0, A, B, C and D were 70%, 58%, 34%, 11% and 4%, respectively. The proportion of BCLC stage 0 increased from 6.2% to 11.3%. Multivariate analysis showed that being female, older age, diagnostic year, BCLC stages, hospital level, body mass index, smoking, alcohol consumption, AFP, Child-Pugh classification and HBV/HCV status were independent predictors for survival. In recent decades, the overall survival of HCC in Taiwan has been improving and might be partly associated with increased BCLC 0 and Child-Pugh A patients, while with the consequent age of patients increasing over time. The proportion of viral-related HCC is decreasing, while nonviral-related HCC is increasing.

Sustained viral response and relapse after discontinuation of oral antiviral drugs in HBeAg-positive patients with chronic hepatitis B infection

Objective

To investigate the sustained virological response and relapse in chronic hepatitis B (CHB) patients with hepatitis B e antigen (HBeAg) positive after stopping oral antiviral drugs, and to monitor the disease progression and the incidence of adverse events such as liver cirrhosis and hepatocellular carcinoma.

Methods

This is a prospective observational study. Patients who continued nucleos(t)ide analogue (NA) treatment after achieving HBeAg seroconversion for more than 3 years were enrolled. After signing the informed consent form, patients stopped NA treatment and received follow-up. During the follow-up, the antiviral treatment information of the patients was collected, and the follow-up observation was carried out every 3 months since the enrollment. We monitored the virological indexes, liver and kidney function, serology and liver imaging during follow-up. The purpose of this study was to explore the sustained virological response rate, HBV DNA recurrence rate, clinical relapse rate and the related factors after drug withdrawal.

Results

A total of 82 patients were enrolled, including 42 males (51.22%) and 40 females (48.78%), with a median age of 34.00 (31.00, 37.25) years. All enrolled patients were followed up for 1 year. At the end of the follow-up, 36.59% (30/82) of patients had sustained virological response, 63.41% (52/82) of patients had HBV DNA reactivation, 17.07% (14/82) of patients had clinical relapse, and 10.98% (9/82) of patients had HBeAg reversion. During the follow-up, there were no adverse events such as liver cirrhosis and hepatocellular carcinoma. The median level of hepatitis B surface antigen (HBsAg) in patients with sustained virological response was lower than that in patients with HBV DNA reactivation (2.92 vs.3.18 log₁₀IU/ml, Z=-1.492/P=0.136), and the median level of baseline HBsAg in patients with HBV DNA reactivation was lower than that in patients with clinical relapse (3.01 vs.3.45 log₁₀IU/mL, Z=-1.795/P=0.073), but the difference was not significant. There was no significant statistical difference between patients with sustained virological response and HBV DNA reactivation of the median total treatment time [69.50 (56.25, 86.00) vs.62.50 (44.00, 88.50) months, Z=-0.689/P=0.491], and the consolidation treatment time [41.50 (36.75, 54.75) vs.40.50 (36.00, 53.75) months, Z=-0.419/P=0.675].

Conclusion

The sustained virological response rate of HBeAg positive CHB patients after stopping oral antiviral treatment is lower, and it is more common in patients with lower HBsAg levels. Patients still need to be closely monitored after stopping NA therapy.

Hepatitis B functional cure and immune response

Hepatitis B virus (HBV) is a hepatotropic virus, which damage to hepatocytes is not direct, but through the immune system. HBV specific CD4+ T cells can induce HBV specific B cells and CD8+ T cells. HBV specific B cells produce antibodies to control HBV infection, while HBV specific CD8+ T cells destroy infected hepatocytes. One of the reasons for the chronicity of HBV infection is that it cannot effectively activate adoptive immunity and the function of virus specific immune cells is exhausted. Among them, virus antigens (including HBV surface antigen, e antigen, core antigen, etc.) can inhibit the function of immune cells and induce immune tolerance. Long term nucleos(t)ide analogues (NAs) treatment and inactive HBsAg carriers with low HBsAg level may "wake up" immune cells with abnormal function due to the decrease of viral antigen level in blood and liver, and the specific immune function of HBV will recover to a certain extent, thus becoming the "dominant population" for functional cure. In turn, the functional cure will further promote the recovery of HBV specific immune function, which is also the theoretical basis for complete cure of hepatitis B. In the future, the complete cure of chronic HBV infection must be the combination of three drugs: inhibiting virus replication, reducing surface antigen levels and specific immune regulation, among which specific immunotherapy is indispensable. Here we review the relationship, mechanism and clinical significance between the cure of hepatitis B and immune system.

Ivermectin Inhibits HBV Entry into the Nucleus by Suppressing KPNA2

Hepatitis B virus (HBV) specifically infects human hepatocytes and increases the risks of cirrhosis and liver cancer. Currently, nucleic acid analogs are the main therapeutics for chronic hepatitis caused by HBV infection. Although nucleic acid analogs can eliminate HBV DNA by inhibiting HBV reverse transcriptase, they cannot lead to negative conversion of covalently closed circular DNA (cccDNA) and hepatitis B surface antigen (HBsAg). In this study, we revealed that the antifilarial drug ivermectin suppresses HBV production by a different mechanism from the nucleic acid analog entecavir or Na⁺ taurocholate co-transporting polypeptide-mediated entry inhibitor cyclosporin A. Ivermectin reduced the levels of several HBV markers, including HBsAg, in HBV-infected human hepatocellular carcinoma cells (HepG2-hNTCP-C4 cells) and humanized mouse hepatocytes (PXB hepatocytes). In addition, ivermectin significantly decreased the expression of HBV core protein and the nuclear transporter karyopherin α2 (KPNA2) in the nuclei of HepG2-hNTCP-C4 cells. Furthermore, depletion of KPNA1-6 suppressed the production of cccDNA. These results suggest that KPNA1-6 is involved in the nuclear import of HBV and that ivermectin suppresses the nuclear import of HBV by inhibiting KPNA2. This study demonstrates the potential of ivermectin as a novel treatment for hepatitis B.

Hepatitis B flare: the good, the bad and the ugly

INTRODUCTION

Hepatitis B flare, defined as an event of abrupt ALT elevation to >5x ULN, is a frequent episode during the natural course or during/after antiviral therapy of chronic HBV infection, in both HBeAg-positive and HBeAg-negative patients with chronic hepatitis B or liver cirrhosis.

AREAS COVERED

The definition, pathogenesis, clinical presentation, and management of hepatitis B flares in the published literature were reviewed. Hepatitis B flares have been considered as a result of the robust immune response of the patient to an upsurging HBV/HBV-antigen(s). 'Host-dominating flares,' reflect effective immune response, may resolve with ALT normalization and decline of HBV/ antigen(s). Contradictorily, 'virus-dominating flares,' reflect ineffective immune response, are usually followed by persistent/intermittent hepatitis and may even develop hepatic decompensation/failure.

EXPERT OPINION

Not all hepatitis B flares require antiviral therapy, and close observation with combined HBsAg/ALT kinetics along the ascending ALT during hepatitis flare may differentiate hepatitis flares for an appropriate treatment/retreatment decision. More studies are needed to verify this proposal. Further immunologic studies using multiple samples during hepatitis B flare are important to clarify the precise underlying mechanisms as the basis for further improvement in the management of hepatitis flare.

Robust antiviral responses in severe hepatitis flare persist after early retreatment cessation and lead toward hepatitis B surface antigen loss: A proof-of-concept study

AIM

Hepatitis B flare has been interpreted as result of immune response against upsurging hepatitis B virus (HBV) and its antigen(s) that may lead to HBV decline/clearance spontaneously. It has been speculated that antiviral therapy could halt the effective immune response with viral persistent as a consequence. A proof-of-concept study was conducted to investigate this issue.

METHODS

Serial biochemical, quantitative hepatitis B surface antigen (HBsAg), interferon-γ (IFN-γ) and tumor-necrosis factor-α (TNF-α) assays were performed in four patients with severe hepatitis flare who had achieved precipitous HBsAg decline within 4 weeks of antiviral therapy.

RESULTS

TNF-α and IFN-γ were found to be elevated in parallel to upsurging HBV DNA and HBsAg levels in all patients. Higher levels of TNF-α and IFN-γ and levels relative to qHBsAg were observed during and after early termination of therapy within 4 weeks in two patients and were followed by further HBsAg decline to <5 IU/ml and even achieved HBsAg loss in one patient. The patient who had stopped therapy on day 44 showed minimal HBsAg decline afterward and the patient who continued therapy showed a 10-fold rebound of qHBsAg from its nadir. The subsequent IFN-γ and TNF-α activity of these two patients was minimal.

CONCLUSIONS

The results suggest that patients with severe hepatitis flare who achieved precipitous HBsAg decline may have robust immune response to clear the virus, and early termination of antiviral therapy may allow the protective immune response to continue and accelerate HBV decline toward HBsAg loss.

Hepatitis B x (HBx) as a Component of a Functional Cure for Chronic Hepatitis B

Patients who are carriers of the hepatitis B virus (HBV) are at high risk of chronic liver disease (CLD) which proceeds from hepatitis, to fibrosis, cirrhosis and to hepatocellular carcinoma (HCC). The hepatitis B-encoded X antigen, HBx, promotes virus gene expression and replication, protects infected hepatocytes from immunological destruction, and promotes the development of CLD and HCC. For virus replication, HBx regulates covalently closed circular (ccc) HBV DNA transcription, while for CLD, HBx triggers cellular oxidative stress, in part, by triggering mitochondrial damage that stimulates innate immunity. Constitutive activation of NF-κB by HBx transcriptionally activates pro-inflammatory genes, resulting in hepatocellular destruction, regeneration, and increased integration of the HBx gene into the host genome. NF-κB is also hepatoprotective, which sustains the survival of infected cells. Multiple therapeutic approaches include direct-acting anti-viral compounds and immune-stimulating drugs, but functional cures were not achieved, in part, because none were yet devised to target HBx. In addition, many patients with cirrhosis or HCC have little or no virus replication, but continue to express HBx from integrated templates, suggesting that HBx contributes to the pathogenesis of CLD. Blocking HBx activity will, therefore, impact multiple aspects of the host–virus relationship that are relevant to achieving a functional cure.

Arthrospira Enhances Seroclearance in Patients with Chronic Hepatitis B Receiving Nucleos(t)ide Analogue through Modulation of TNF-α/IFN-γ Profile

Chronic hepatitis B (CHB) virus infection, causing immune dysfunction and chronic hepatitis, is one of the leading risk factors for hepatocellular cancer. We investigated how Arthrospira affected hepatitis B surface antigen (HBsAg) reduction in CHB patients under continued nucleos(t)ide analogues (NA). Sixty CHB patients who had been receiving NA for at least one year with undetectable HBV DNA were randomized into three groups: control and oral Arthrospira at 3 or 6 g daily add-on therapy groups. Patients were followed up for 6 months. Oral Arthrospira-diet mice were established to investigate the possible immunological mechanism of Arthrospira against HBV. Within 6 months, mean quantitative HBsAg (qHBsAg) decreased in the oral Arthrospira add-on therapy group. Interestingly, interferon gamma (IFN-γ) increased but TNF-α, interleukin 6 (IL-6), hepatic fibrosis, and steatosis decreased in the add-on groups. In mice, Arthrospira enhanced both innate and adaptive immune system, especially natural killer (NK) cell cytotoxicity, B cell activation, and the interleukin 2 (IL-2), IFN-γ immune response. Arthrospira may modulate IL-2- and TNF-α/IFN-γ-mediated B and T cell activation to reduce HBsAg. Also, Arthrospira has the potential to restore immune tolerance and enhance HBsAg seroclearance in CHB patients through promoting T, B, and NK cell activation.

Impact of National Centralized Drug Procurement Policy on Antiviral Utilization and Expenditure for Hepatitis B in China

BACKGROUND AND AIMS

The National Centralized Drug Procurement (NCDP) policy was launched in mainland China in April 2019, with entecavir (ETV) and tenofovir disoproxil fumarate (TDF) being included in the procurement list. We conducted the current study to investigate the impact of the NCDP policy on the utilization and expenditures of antiviral therapy for chronic hepatitis B (CHB) in China.

METHODS

Procurement records, including monthly purchase volume, expenditure, and price of nucleos(t)ide analogs (NAs), were derived from the National Healthcare Security Administration from April 2018 to March 2021. The changes in volumes and expenditures of the first-line NAs and bid-winning products were calculated. The effects of price, volume, and structure related to drug expenditure were calculated by the Addis and Magrini (AM) Index System Analysis.

RESULTS

The purchase volume of NAs significantly increased from 134.3 to 318.3 million DDDs, whereas the expenditure sharply decreased from 1,623.41 to 490.43 million renminbi (RMB) or 241.94 to 73.09 million US dollars (USD). The proportions of first-line NAs rose from 72.51% (ETV: 69.00%, TDF: 3.51%) to 94.97% (ETV: 77.42%, TDF: 17.55%). AM analysis showed that the NCDP policy decreased the expenditure of all NAs (S=0.91) but increased that of the first-line NAs in the bid-winning list (S=1.13). Assuming the population size of CHB patients remains stable and a compliance rate of ≥75%, the proportion of CHB patients receiving first-line antiviral therapy would increase from 6.36-8.48% to 11.56-15.41%.

CONCLUSIONS

The implementation of the NCDP policy significantly increased the utilization of first-line NAs for CHB patients at a lower expenditure. The findings provided evidence for optimizing antiviral therapy strategy and allocating medical resources in China.

Promising Role of Emodin as Therapeutics to Against Viral Infections

Emodin is an anthraquinone derivative that is widely present in natural plants and has a wide spectrum of pharmacological effects, such as antibacterial, anti-inflammatory, anti-fibrotic and anticancer and so on. Through reviewing studies on antiviral effect of emodin in the past decades, we found that emodin exhibits ability of inhibiting the infection and replication of more than 10 viruses in vitro and in vivo, including herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2), human cytomegalovirus (HCMV), Epstein-Barr virus (EBV), coxsackievirus B (CVB), hepatitis B virus (HBV), influenza A virus (IAV), SARS-CoV, viral haemorrhagic septicaemia rhabdovirus (VHSV), enterovirus 71 (EV71), dengue virus serotype 2 (DENV-2) and Zika virus (ZIKV). Therefore, this review aims to summarize the antiviral effect of emodin, in order to provide reference and hopes to support the further investigations.