Sustained immune control in HBeAg-positive patients who switched from entecavir therapy to pegylated interferon-α2a: 1 year follow-up of the OSST study

Current trends and advances in antiviral therapy for chronic hepatitis B

ABSTRACT

Chronic hepatitis B virus (HBV) infection is a global public health concern. Existing antiviral drugs, including nucleos(t)ide analogs and interferon-α, can suppress HBV replication and improve the prognosis. However, the persistence of covalently closed circular DNA (cccDNA), the integration of HBV-DNA into the host genome, and compromised immune responses impede the successful treatment of hepatitis B. While achieving a functional cure of HBV remains elusive with the current treatment methods, this is the goal of new therapeutic approaches. Therefore, developing novel antiviral drugs is necessary for achieving a functional or complete cure for chronic hepatitis B. In recent years, substantial progress has been made in drug discovery and development for HBV infection. Direct-acting antiviral agents such as entry inhibitors, capsid assembly modulators, subviral particle release inhibitors, cccDNA silencers, and RNA interference molecules have entered clinical trials. In addition, several immunomodulatory agents, including toll-like receptor agonists, therapeutic vaccines, checkpoint inhibitors, and monoclonal antibodies, are also making their way toward clinical use. In this review, we summarize the recent progress and limitations of chronic hepatitis B treatment and discuss perspectives on approaches to achieving functional cure. Although it will take some time for these new antiviral drugs to be widely used in clinical practice, combination therapy may become a preferable treatment option in the future.

Hepatitis B cure: Current situation and prospects

Achievement of a 'clinical cure' in chronic hepatitis B (CHB) implies sustained virological suppression and immunological control over the infection, which is the ideal treatment goal according to domestic and international CHB management guidelines. Clinical practice has shown encouraging results for specific patient cohorts using tailored treatment regimens. These regimens incorporate either nucleos(t)ide analogs, immunomodulatory agents such as pegylated interferon α, or a strategic combination of both, sequentially or concurrently administered. Despite these advancements in the clinical handling of hepatitis B, achieving a clinical cure remains elusive for a considerable subset of patients due to the number of challenges that preclude the realization of optimal treatment outcomes. These include, but are not limited to, the emergence of antiviral resistance, incomplete immune recovery, and the persistence of covalently closed circular DNA. Moreover, the variance in response to interferon therapy and the lack of definitive biomarkers for treatment cessation also contribute to the complexity of achieving a clinical cure. This article briefly overviews the current research progress and existing issues in pursuing a clinical cure for hepatitis B.

Guidelines for the Prevention and Treatment of Chronic Hepatitis B (version 2022)

To facilitate the achieving of the goal of "eliminating viral hepatitis as a major public health threat by 2030" set by the World Health Organization, the Chinese Society of Hepatology together with the Chinese Society of Infectious Diseases (both are branches of the Chinese Medical Association) organized a panel of experts and updated the guidelines for prevention and treatment of chronic hepatitis B in China (version 2022). With the support of available evidence, this revision of the guidelines focuses on active prevention, large scale testing, and expansion of therapeutic indication of chronic hepatitis B with the aim of reducing the hepatitis B related disease burden.

Clinical cure of hepatitis B: Delight and anticipation

Chronic hepatitis B (CHB) patients achieving clinical cure represent individuals who have attained persistent virological suppression and immunological control. This is the ideal treatment goal in both domestic and international CHB management guidelines. Clinical practice has demonstrated promising outcomes for certain patient populations treated with optimized regimens involving nucleos(t)ide analogs (NAs) or immunomodulators (such as pegylated interferon α) administered sequentially or in combination. However, despite the gratifying progress in the clinical management of hepatitis B, a significant number of patients still cannot achieve the goal of clinical cure. Many challenges remain to be overcome to achieve better treatment outcomes. This article provides a brief overview of the current research progress and existing issues in the pursuit of clinical cure of hepatitis B.

The efficacy and safety of adding on or switching to peginterferon α-2b in HBeAg-positive chronic hepatitis B patients with long-term entecavir treatment: a multicentre randomised controlled trial

BACKGROUND & AIMS

The strategies of adding on or switching to peginterferon (PEG-IFN) improved the serological response rates in patients with chronic hepatitis B (CHB) who had previously experienced treatment with nucleos(t)ide analogues. However, robust data on which combination strategy is more effective remain lacking.

METHODS

In this multicentre, parallel, open-label, randomised, controlled trial, patients with HBeAg-positive CHB who were treated with entecavir ≥2 years, and had hepatitis B surface antigen (HBsAg) <3000 IU/ml, HBeAg <200S/CO and HBV DNA <50 IU/ml were randomly assigned in a 1:1:1 ratio to add on PEG-IFN, switch to PEG-IFN or continue entecavir monotherapy for 48 weeks. The primary endpoint was HBeAg seroconversion at week 48.

RESULTS

A total of 153 patients were randomised into three treatment arms (50 in add-on, 52 in switch-to and 51 in monotherapy). Compared with continuous entecavir monotherapy, both add-on and switch-to strategies achieved higher rates of HBeAg seroconversion (18.0% vs. 2.0%, p = 0.007; 19.2% vs. 2.0%, p = 0.005, respectively), HBeAg loss (24.0% vs. 5.9%, p = 0.010; 23.1% vs. 5.9%, p = 0.013, respectively), HBsAg < 100 IU/ml (30.0% vs. 0%, p < 0.001; 34.6% vs. 0%, p < 0.001, respectively), and higher HBsAg reduction (-0.90 vs. -0.06 log₁₀ IU/ml, p < 0.001; -0.92 vs. -0.06 log₁₀ IU/ml, p < 0.001, respectively) at week 48. The efficacy was comparable between add-on and switch-to arms (p > 0.05). Adverse events were mainly related to PEG-IFN but generally tolerable.

CONCLUSION

In patients with CHB who achieved virological response with long-term entecavir, both adding on and switching to PEG-IFN are alternative strategies resulting in higher rates of HBeAg seroconversion and HBsAg reduction than continuous entecavir.

CLINICAL TRIALS REGISTRATION

Chinese Clinical Trial Registry (www.chictr.org.cn, identifier: ChiCTR-IPR-17012055).

Interferon add-on therapy increased clinical cure significantly for interferon-experienced chronic hepatitis B patients with low HBsAg

Currently, interferon add-on therapy brings hope for clinical cure of chronic hepatitis B patients with low HBsAg. However, in clinical practice patients with poor responses to their first interferon therapy were often switched to nucleos(t)ide analog therapy and then labeled as unsuitable patients for interferon therapy. Even if their HBsAg levels dropped to a low level, they were reluctant or not recommended to take interferon again, which caused them to miss out on interferon add-on therapy and clinical cure. Therefore, it is urgent to elucidate the effectiveness of interferon add-on therapy to get clinical cure for these interferon-experienced patients with low HBsAg. The purpose of this study was to investigate whether interferon-experienced patients could achieve the same HBsAg clearance and HBsAg seroconversion rates as interferon-naive patients. Also, the associated factor of HBsAg clearance and seroconversion were aimed to be clarified. 292 patients, including 85 interferon-experienced patients, were enrolled with HBsAg< 1500 IU/ml, HBeAg negative and HBV-DNA negative. And then, peg-interferon α-2b add-on therapy was performed. The results showed that the week 48 HBsAg clearance and seroconversion rates of all patients were 29.8% and 22.0%. There was no statistically significant difference between interferon-experienced and interferon-naive patients in week 48 HBsAg clearance and seroconversion rates, suggesting satisfactory clinical cure of the interferon add-on therapy for interferon-experienced patients. The age, baseline HBsAg, and week 12 HBsAg were negative correlated factors for week 48 HBsAg clearance and seroconversion. Furthermore, the age, baseline HBsAg and week 12 HBsAg for predicting the week 48 HBsAg clearance were cut off at 40.5 years, at 152.0 IU/ml and at 34.99 IU/ml, and for predicting seroconversion were cut off at 40.5 years, at 181.9 IU/ml and at 34.99 IU/ml, correspondingly. Significantly, interferon-experienced patients with low HBsAg were suggested with interferon add-on therapy to achieve clinical cure as soon as possible. This research provided evidences and cut-offs for the interferon add-on therapy against chronic hepatitis B.

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

BACKGROUND & AIMS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

GOV IDENTIFIER

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

Novel therapeutic strategies for Chronic Hepatitis B

The last few years have seen a resurgence of activity in the hepatitis B drug pipeline, with many compounds in various stages of development. This review aims to provide a comprehensive overview of the latest advances in therapeutics for chronic hepatitis B (CHB). We will discuss the broad spectrum of direct-acting antivirals in clinical development, including capsids inhibitors, siRNA, HBsAg and polymerase inhibitors. In addition, host-targeted therapies (HTT) will be extensively reviewed, focusing on the latest progress in immunotherapeutics such as toll-like receptors and RIG-1 agonists, therapeutic vaccines and immune checkpoints modulators. A growing number of HTT in pre-clinical development directly target the key to HBV persistence, namely the covalently closed circular DNA (cccDNA) and hold great promise for HBV cure. This exciting area of HBV research will be highlighted, and molecules such as cyclophilins inhibitors, APOBEC3 deaminases and epigenetic modifiers will be discussed.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Cost-effectiveness of combination antiviral treatment with extended duration for hepatitis B e antigen (HBeAg)-negative chronic hepatitis B in China

Background

Hepatitis B surface antigen clearance or seroconversion is rarely achieved for patients using nucleoside analogs or pegylated interferon alpha monotherapy approaches. Several recent studies have confirmed the benefit of a combination of these two approaches for selected chronic hepatitis B patients. However, few reports have investigated long-term outcomes or health economic evaluation for hepatitis B surface antigen clearance. The aim of this study was to perform a cost-effectiveness analysis of the long-term use of this combination strategy among selected hepatitis B e antigen-negative patients.

Methods

Drawing on experience in China, we used a Markov model to simulate disease progression among a population of hepatitis B e antigen-negative chronic hepatitis B patients with surface antigen levels of ≤1,000 IU/mL through a discrete series of health states. We compared nucleoside analog monotherapy to the combination strategy over a prolonged period. We measured lifetime costs, quality-adjusted life-years and incremental cost-effectiveness ratios.

Results

The combination therapy produced 15.8 quality-adjusted life-years, and cost US dollars (USD) 45,032 per patient. The monotherapy gave 13.9 quality-adjusted life-years, and had a cost of USD 52,064. The incremental cost-effectiveness ratio of the monotherapy (USD −3,755 per quality-adjusted life-year) did not obtain extended dominance over combination therapy. The most cost-effective option was combination therapy among patients with hepatitis B surface antigen levels of ≤10 IU/mL, which had the lowest calculated cost of USD 35,318 and most quality-adjusted life-years (16.7).

Conclusions

A long-term combination treatment strategy for selected hepatitis B e antigen-negative chronic hepatitis B patients may prolong quality-adjusted life-years compared with nucleoside analog monotherapy. Chronic hepatitis B patients with a hepatitis B surface antigen level of ≤10 IU/mL were the most cost-effective population under this strategy.

Controversies in Treating Chronic HBV: The Role of PEG-interferon-alfa

Pegylated interferon-alpha therapy is one of the first-line chronic hepatitis B treatment. Finite treatment duration, absence of drug resistance, delayed response, and higher hepatitis B surface antigen loss than nucleos(t)ides analog therapy are the advantages of pegylated interferon-alpha treatment. Common side effects and subcutaneous injections requirement limit its use. Identifying patients likely to respond to pegylated interferon-alpha and optimizing treatment is reasonable. Motivating patients to complete the 48-week treatment is necessary. Treatment is stopped or switched to other treatment strategies in patients with stopping rule criteria. Combination therapy with nucleos(t)ides analog may improve response, but remains controversial.

Guidelines for Prevention and Treatment of Chronic Hepatitis B

To achieve the goal of the World Health Organization to eliminate viral hepatitis as a major public health threat by 2030, the Chinese Society of Infectious Diseases and the Chinese Society of Hepatology convened an expert panel in 2019 to update the guidelines for the prevention and treatment of chronic hepatitis B (CHB). The current guidelines cover recent advances in basic, clinical, and preventive studies of CHB infection and consider the actual situation in China. These guidelines are intended to provide support for the prevention, diagnosis, and treatment of CHB.

Analysis of the Efficacy and Safety of PEGylated Interferon-α2b Treatment in Inactive Hepatitis B Surface Antigen Carriers

Introduction

Hepatitis B virus (HBV) infection is associated with the onset of several major liver diseases. Inactive hepatitis B surface antigen (HBsAg) carriers (IHCs) may be successfully treated with PEGylated interferon-α2b (PEG-IFNα2b)-based antiviral therapy; however, studies on this treatment have been insufficient. In this study, we evaluated the efficacy and safety of PEG-IFNα2b treatment in IHCs.

Methods

Nineteen IHCs were treated with subcutaneous PEG-IFNα2b (180 μg/week) for 48 weeks (treatment group). Patients were followed up for 24 weeks after treatment discontinuation. Twenty untreated control patients were observed for 72 weeks (control group). HBsAg clearance (HBsAg < 0.05 IU/mL), HBsAg seroconversion, and alanine aminotransferase levels were monitored.

Results

Of the 19 patients treated with PEG-IFNα2b, 16 showed HBsAg loss (84.2%), and 13 showed HBsAg seroconversion (68.4%) at 72 weeks. All patients in the treatment group exhibited virological response (serum HBV DNA level < 10 IU/mL) at the time of drug withdrawal. In the control group, no patients experienced HBsAg loss during the observational period. There were no serious adverse events during treatment, and the therapy was well tolerated.

Conclusions

Short PEG-IFNα2b therapy in IHCs produced a high functional cure rate and good safety profile, suggesting that PEG-IFNα2b treatment may be the best choice for clinical cure of some IHCs.

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

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

Combination of Entecavir or Tenofovir with Pegylated Interferon-α for Long-Term Reduction in Hepatitis B Surface Antigen Levels: Simultaneous, Sequential, or Add-on Combination Therapy

Seroclearance of hepatitis B surface antigen (HBsAg) (“functional cure”) is the optimal endpoint of antiviral therapy for chronic hepatitis B virus (HBV) infection. Currently available anti-HBV therapy includes nucleoside/nucleotide analogs (NAs) and peginterferon-α (Peg-IFNα). Combination of NAs and Peg-IFNα, each with different mechanisms of action, is an attractive approach for treating chronic HBV infection. In earlier studies, compared with monotherapy using IFNα, combination therapy showed greater on-treatment HBV DNA suppression but no difference in the sustained response. However, responses to the combination of non-pegylated IFNα with lamivudine or adefovir were not assessed based on HBsAg quantification but were defined by normal alanine aminotransferase levels, testing negative for hepatitis B e-antigen, and low HBV DNA load over a short term. Here, we reviewed previous reports regarding the effects of combination therapy of entecavir or tenofovir with Peg-IFNα, focusing on long-term reduction in HBsAg levels. Regimens of combination therapy were classified into “simultaneous” combination (“de novo” strategy); “sequential” combination, which involved starting with one therapy followed by the other (“switch-to” strategy); “add-on” combination, which involved adding Peg-IFNα to an ongoing NAs. Some studies have shown promising results, but there is no robust evidence that combination therapy is superior to monotherapy. Large studies are needed to assess the safety and efficacy of combination therapies to increase the rates of HBsAg seroclearance over the long term.

Interferon-Induced Macrophage-Derived Exosomes Mediate Antiviral Activity Against Hepatitis B Virus Through miR-574-5p

BACKGROUND

Interferon alfa (IFN-α) has been proved effective in treating chronic hepatitis B (CHB), owing to its ability to suppress hepatitis B surface antigen and hepatitis B virus (HBV) covalently closed circular DNA. However, the underlying mechanisms are unclear.

METHODS

We investigated the antiviral activities of exosomes from responders and nonresponders to pegylated IFN-α (PegIFN-α) as well as the supernatants of IFN-α-treated macrophages derived from THP-1 (the human leukemia monocyte cell line). Then the expression profiles of exosomal microRNAs (miRNAs) were analyzed using miRNA sequencing. The luciferase reporter assay was used to locate the binding position of HBV genomic sequence targeted by the identified miRNA.

RESULTS

Exosomes from PegIFN-α-treated patients, particularly responders, as well as the supernatants of IFN-α-treated macrophages exhibited anti-HBV activities, as manifested by the suppression of hepatitis B surface antigen, hepatitis B e antigen, HBV DNA, and covalently closed circular DNA levels in HBV-related cell lines. PegIFN-α treatment up-regulated exosomal hsa-miR-193a-5p, hsa-miR-25-5p, and hsa-miR-574-5p, which could partially inhibit HBV replication and transcription, and hsa-miR-574-5p reduced pregenomic RNA and polymerase messenger RNA levels by binding to the 2750-2757 position of the HBV genomic sequence.

CONCLUSIONS

Exosomes can transfer IFN-α-related miRNAs from macrophages to HBV-infected hepatocytes, and they exhibit antiviral activities against HBV replication and expression.

Entecavir Plus Pegylated Interferon and Sequential HBV Vaccination Increases HBsAg Seroclearance: A Randomized Controlled Proof-of-Concept Study

BACKGROUND

HBsAg seroclearance is considered a functional cure for patients with chronic hepatitis B, but is rarely achievable with oral nucleos(t)ide analogs alone. We conducted a randomized controlled proof-of-concept trial to evaluate the impact of adding pegylated interferon (Peg-IFN) alfa-2a plus sequential or concomitant hepatitis B virus (HBV) vaccination.

METHODS

A total of 111 patients who achieved serum HBV DNA <20 IU/mL and quantitated HBsAg (qHBsAg) <3,000 IU/mL with entecavir were randomly assigned (1:1:1) to the E+sVIP group (entecavir + Peg-IFN alfa-2a [180 µg every week over 48 weeks] + sequential HBV vaccination [20 µg of HBsAg on weeks 52, 56, 60, and 76]), E+cVIP group (entecavir + Peg-IFN alfa-2a + concomitant HBV vaccination [weeks 4, 8, 12, and 28]), or the control group (entecavir only). The primary endpoint was HBsAg seroclearance at week 100 and secondary endpoints included safety.

RESULTS

No differences in baseline qHBsAg were observed among the groups. The E+sVIP group in the intention-to-treat analysis showed a significantly higher chance of HBsAg seroclearance during week 100 than the control group (16.2% vs. 0%, P=0.025), but the E+cVIP group (5.4%) failed to reach a significant difference (P=0.54). Adverse events were significantly more frequent in the E+sVIP (81.1%) or E+cVIP group (70.3%) than the control group (2.7%) (both P<0.0001). However, the frequency of serious adverse events did not differ significantly among three groups (2.7%, 5.4%, and 2.7%, respectively; P=1.00).

CONCLUSIONS

Entecavir plus an additional Peg-IFN alfa-2a treatment followed by sequential HBV vaccination under an intensified schedule significantly increases the chance of HBsAg seroclearance compared to entecavir alone.

Roadmap to functional cure of chronic hepatitis B: An expert consensus

Hepatitis B virus (HBV) infection continues to be a major public health issue worldwide. HBsAg loss is associated with functional remission and improved long-term outcome, and is considered to be a 'functional cure' (also referred to as clinical or immunologic cure) for chronic hepatitis B. This ideal goal of therapy can be achieved using optimized combination regimens with direct-acting antivirals [eg nucleos(t)ide analogues (NAs)] and immunomodulators [eg pegylated interferon alpha2a (Peg-IFN)] in selected patients with chronic hepatitis B. Among different combination therapies currently available, those with NA lead-in followed by Peg-IFN in virally suppressed patients has been demonstrated to be effective. This review provides an updated overview of the evidence supporting the use of combination therapies and summarizes expert consensus on the roadmap to attain functional cure for chronic hepatitis B patients.

Pegylated-interferon consolidation treatment versus nucleos(t)ide analogue consolidation treatment in non-cirrhotic hepatitis B patients with hepatitis B e antigen seroconversion: an open-label pilot trial

BACKGROUND

The safety of nucleos(t)ide analogue (NA) treatment cessation remains one of the most controversial topics in the management of chronic hepatitis B (CHB) patients. This study investigated the efficiency of 48-week pegylated-interferon (peg-IFN) alfa-2a consolidation therapy on viral relapse after discontinued NA treatment in CHB patients who achieved hepatitis B e antigen (HBeAg) seroconversion for > 1 year.

METHODS

NA-treated HBeAg-positive patients who achieved the standard of discontinued NA treatment (i.e. time of HBeAg seroconversion > 1 year) were randomly assigned to receive peg-IFN consolidation (n = 24) treatment or continue original NA therapy (n = 24) for 48 weeks. The treatments were then discontinued, and the patients were observed up to 144 weeks. The primary endpoint was the proportion of patients with viral relapse at week 144 among those who received at least one dose of study drug or had at least one study visit [modified intention-to-treat population (mITT)].

RESULTS

Of the 24 patients who received peg-IFN treatment, 6 (25%) experienced viral relapse and 8 (36.3%) showed HBsAg loss during 96 weeks of treatment-free follow-up. Of the patients who underwent NA consolidation treatment, only 1 (4.3%) of 23 patients showed HBsAg loss and 14 (58.3%) of 24 patients experienced viral relapse during follow-up. HBsAg level decline < 0.25 log₁₀ IU/mL at week 96 was significantly associated with viral relapse.

CONCLUSION

A 48-week peg-IFN alfa-2a consolidation therapy increased the rate of HBsAg loss and sustained viral replication suppression in HBeAg-positive patients who achieved HBeAg seroconversion for > 1 year after NA treatment discontinuation.

Sequential combination therapy with interferon, interleukin-2 and therapeutic vaccine in entecavir-suppressed chronic hepatitis B patients: the Endeavor study

BACKGROUND

Switching from nucleos(t)ide analogues to interferon (IFN) improves hepatitis B surface antigen (HBsAg) loss. We aimed to evaluate whether combining immunomodulators such as interleukin-2 (IL-2) and therapeutic vaccine with IFN enhances HBsAg loss in entecavir (ETV)-suppressed patients.

METHODS

Ninety-four patients exhibiting virological suppression and hepatitis B e antigen (HBeAg) loss following ETV treatment were randomized 1:1:1 to receive ETV (group I) or IFN (group II) for 48 weeks, or IFN and vaccine for 48 weeks plus IL-2 for 12 weeks (group III). The primary endpoint was HBsAg loss at week 48. Peripheral natural killer (NK) cells and regulatory T cells (Treg) were measured as immune checkpoint indicators.

RESULTS

Mean HBsAg decline at week 48 was significantly greater in group III (0.85 log 10 IU/mL) and group II (0.74 log 10 IU/mL), than in group I (0.13 log 10 IU/mL). At week 48, 9.38%, 3.03%, and 3.70% of subjects in group III, II, and I, respectively, achieved HBsAg loss. Among patients with baseline HBsAg titers ranging from 100 to 1500 IU/mL, HBsAg loss rate was 27.3, 7.1, and 0% in group III, II, and I, respectively. Responders in group III showed a significantly higher increase in CD56^bright CD16^-NK cells from week 24 to 36, and a significant decline in Treg from week 12 to 24 than non-responders.

CONCLUSION

For ETV-suppressed patients, particularly those with low baseline HBsAg levels, combination therapy with IFN and other immunomodulators may enhance HBsAg loss, while successful response correlates with partial restoration of NK cells and Tregs.

Low hepatitis B surface antigen and HBV DNA levels predict response to the addition of pegylated interferon to entecavir in hepatitis B e antigen positive chronic hepatitis B

BACKGROUND

Various treatment combinations of peginterferon (PEG-IFN) and nucleos(t)ide analogues have been evaluated for chronic hepatitis B (CHB), but the optimal regimen remains unclear.

AIMS

To study whether PEG-IFN add-on increases response compared to entecavir (ETV) monotherapy, and whether the duration of ETV pretreatment influences response.

METHODS

Response was evaluated in HBeAg positive patients previously treated in two randomized controlled trials. Patients received ETV pretreatment for at least 24 weeks and were then allocated to 24-48 weeks of ETV+PEG-IFN add-on, or continued ETV monotherapy. Response was defined as HBeAg loss combined with HBV DNA <200 IU/mL 48 weeks after discontinuing PEG-IFN.

RESULTS

Of 234 patients, 118 were assigned PEG-IFN add-on and 116 continued ETV monotherapy. Response was observed in 38/118 (33%) patients treated with add-on therapy and in 23/116 (20%) with monotherapy (P = 0.03). The highest response to add-on therapy compared to monotherapy was observed in PEG-IFN naive patients with HBsAg levels below 4000 IU/mL and HBV DNA levels below 50 IU/mL at randomization (70% vs 34%; P = 0.01). Above the cut-off levels, response was low and not significantly different between treatment groups. Duration of ETV pretreatment was associated with HBsAg and HBV DNA levels (both P < 0.005), but not with response (P = 0.82).

CONCLUSIONS

PEG-IFN add-on to ETV therapy was associated with higher response compared to ETV monotherapy in patients with HBeAg positive CHB. Response doubled in PEG-IFN naive patients with HBsAg below 4000 IU/mL and HBV DNA below 50 IU/mL, and therefore identifies them as the best candidates for PEG-IFN add-on (Identifiers: NCT00877760, NCT01532843).

Antiviral Therapy for AECHB and Severe Hepatitis B (Liver Failure)

This chapter describes the principles of antiviral therapy, treatment strategies, medications and recommendations for AECHB, HBV-ACLF, HBV-related liver cirrhosis, HBV-related HCC, and liver transplantation.

Severe exacerbation of chronic hepatitis B is closely related to continuous HBV replication. Therefore, inhibiting HBV replication to reduce viral load may block disease progression and improve the quality of life of these patients. ETV or TDF has been recommend first-line drug for the treatment of AECHB.

A hyperactive immune response due to continuous HBV replication is the main mechanism for development of severe hepatitis B. In addition to comprehensive treatment, early administration of potent nucleoside analogs can rapidly reduce HBV DNA concentration, relieve immune injury induced by HBV, and reduce liver inflammation and patient mortality. Antiviral agents have become important in the treatment of severe exacerbation of chronic hepatitis B.

Long-term antiviral treatment with nucleoside analogs can delay or reverse the progress of liver cirrhosis. Virologic response, viral resistance and adverse drug reactions should be closely monitored during treatment. The treatment should be optimized for maximum effect based on each patient’s responses.

Effective antiviral therapy can suppress HBV replication and reduce the incidence of HBV-related HCC. Patients with HBV-related HCC should receive individualized and optimal multidisciplinary comprehensive treatment. Anti-viral drugs with high efficacy, low resistance and low adverse drug reactions should be selected to improve the patient’s quality of life and prolong survival time.

Methods to prevent HBV reinfection after liver transplantation include passive immunization (HBIG), antiviral treatment (nucleoside analogs) and active immunization (hepatitis B vaccine).

Clinical trials involving sequential combination therapy with NUC and Peg-IFN have shown statistically significant decline in HBsAg levels on treatment and high rates of sustained post-treatment serologic response. Combination therapy with novel DAA and immunotherapeutic approach may hold promise to overcome both cccDNA persistence and immune escape, representing a critical step towards HBV cure.

Prognosis, Prevention and Research Prospects of Progression to Severe Hepatitis B (Liver Failure)

This chapter describes the factors involved in the disease prognosis, parameters of outcome evaluations, principles and techniques for progression prevention. In last section, the future perspectives in both basic and clinical investigations towards unmet medical needs in AECHB and HBV ACLF are discussed.

Factors affecting the prognosis of patients with severe hepatitis B include those related to the virus (including viral load, HBeAg expression, and gene mutation), patient age, co-morbidity, TBil, INR, serum Cr, and the host genetic background. Indicators associated with patient prognosis include TBil, total cholesterol, albumin and prealbumin, hepatic encephalopathy, kidney damage, alpha-fetoprotein and vitamin D binding protein, blood sodium level, virus HBeAg expression and genotype, and blood glucose.

In addition to TBil, INR, hepatic encephalopathy, Cr level and AFP as indicators for prognosis of severe hepatitis, some other parameters such as clinical signs, symptoms, serum levels of total cholesterol and albumin and natrium, and coagulation factors are all valuable in assessment. The roles of cell apoptosis, liver regeneration and immunological parameters in assessing patient prognosis are under study. Prognostic evaluating systems include MELD score, MELD-Na score, iMELD score, KCI and CTP score.

Prevention of severe hepatitis B should be started in asymptomatic patients. Close observation, sufficient rest, adequate nutrition, meticulous nursing and psychological care, preventing and removing exacerbating factors, treating concomitant diseases, reasonable antiviral and comprehensive therapies are helpful to prevent CHB patients from developing to severe hepatitis. For patients who already have severe hepatitis B, the prevention and management of complications is important for lowering mortality rate.

New research directions in acute-on-chronic liver failure include: (1) Additional well controlled studies using present or new liver systems are warranted. Other approaches include the use of granulocyte colony stimulating factor to treat infections as well as the potential of use of stem cells to restore immune integrity and enhance liver regeneration. (2) Using new cell lines and animal models to understand the molecular biology of HBV, the immune response and to develop novel therapies. (3) Development of new anti-HBV strategies, e.g. silencing or remove cccDNA, enhancing immunologic clearance of HBV infection, inhibiting virus entry or HBc expression and using CRISP to disrupt cccDNA.

Switching to peginterferon for chronic hepatitis B patients with hepatitis B e antigen seroconversion on entecavir - A prospective study

Nucleos(t)ide analogues (NA) are effective in suppressing hepatitis B virus (HBV) replication, but most patients require long-term treatment. This study aimed to investigate switching to peginterferon as a strategy to stop NA. Hepatitis B e antigen (HBeAg)-positive chronic hepatitis B patients who developed HBeAg seroconversion during NA treatment were studied. All patients received open-label peginterferon alfa-2a 180 μg/wk for 48 weeks, and NA was stopped at week 4 of peginterferon treatment. The primary endpoint was sustained response, which was defined as negative HBeAg, positive anti-HBe and HBV DNA <2000 IU/mL at week 72. Other secondary endpoints including HBsAg loss at week 72 were also studied. Forty-one patients treated with entecavir for 56 ± 23 months were recruited. Sustained response was achieved in 30 patients (73%, 95% confidence interval 58%-84%). At week 72, 31 (76%) patients had HBeAg seroconversion, 56 (23%) patients had undetectable HBV DNA, 31 (76%) patients had normal ALT, and 6 patients (15%) had HBsAg loss. Baseline HBsAg level was the best predictor for both sustained response and HBsAg loss; the best HBsAg cut-off for sustained response was <1500 IU/mL and that for HBsAg loss was <500 IU/mL by receiver operating characteristic curve analysis. Twenty-two of 25 (88%) patients with baseline HBsAg <1500 IU/mL had sustained response. Five of 10 (50%) patients with baseline HBsAg <500 IU/mL developed HBsAg loss. Switching to peginterferon can be considered as a treatment option in NA-treated patients with HBeAg seroconversion, particularly among those with lower HBsAg levels.

Long-term follow-up of patients treated with entecavir and peginterferon add-on therapy for HBeAg-positive chronic hepatitis B infection: ARES long-term follow-up

Addition of peginterferon alpha (PEG-IFN add-on) to entecavir (ETV) treatment after a short lead-in phase results in more response than ETV monotherapy in HBeAg-positive chronic hepatitis B infection (CHB). This study is the first to assess long-term efficacy of this treatment strategy. Patients who received ETV ± 24 weeks of PEG-IFN add-on in a global trial (ARES study) and completed follow-up were eligible to participate in this observational LTFU study if they had at least one combined HBeAg and HBV DNA measurement beyond week 96 of the ARES study. The primary endpoint was combined response (HBeAg loss and HBV DNA <200 IU/mL) at LTFU. In total, 48 patients treated with PEG-IFN add-on and 48 patients treated with ETV monotherapy were included. The median follow-up duration was 226 (IQR 51) weeks, and 86/96 (90%) patients were initial non-responders. At LTFU, combined response was present in 13 (27%) vs 11 (23%) patients (P = 0.81), and 1 log₁₀  HBsAg decline in 59% vs 28% (P = 0.02) for PEG-IFN add-on and ETV monotherapy, respectively. In 41 initial non-responders who continued ETV therapy, combined response at LTFU was present in 9 patients (PEG-IFN add-on: 5/22 [23%]; ETV monotherapy: 4/19 [21%]). Beyond week 96 of follow-up, rates of serological response became comparable between PEG-IFN add-on and ETV monotherapy. Although in this LTFU study initial non-responders were overrepresented in the add-on arm, PEG-IFN add-on possibly leads rather to accelerated HBeAg loss than to increased long-term HBeAg loss rates.

Systematic review with meta-analysis: combination treatment of regimens based on pegylated interferon for chronic hepatitis B focusing on hepatitis B surface antigen clearance

BACKGROUND

The seroclearance of hepatitis B surface antigen (HBsAg) in patients with chronic hepatitis B (CHB) is considered to be associated with favourable clinical outcomes.

AIMS

This meta-analysis was performed to establish the proportion of HBsAg loss rates among CHB patients who received combination treatment based on pegylated interferon (PegIFN). Four combination strategies have been studied with the aim of improving HBsAg loss: "de novo," "NA-experienced," "switch-to" and "add-on." This meta-analysis was performed to determine which, if any, of these combination strategies was more effective.

METHODS

Medline, Web of Science and Embase databases were searched from inception to December 2017. The proportion of patients who achieved HBsAg loss after combination therapy was pooled using a random-effects model.

RESULTS

Twenty-four studies fulfilled the meta-analysis criteria. The overall pooled proportion suggested that the rate of HBsAg loss could be increased to 9% (95% CI: 7%-12%) based on the combination treatment in CHB patients. Compared with "de novo" strategy (8%, 95% CI: 6%-10%), the "nucleos(t)ide analogues-experienced" (11%, 95% CI: 8%-15%) was found to be more likely (P = 0.036) to achieve a response. Compared with the "add-on" strategy (8%, 95% CI: 5%-13%), the "switch-to" (14%, 95% CI: 9%-20%) was found to be more likely (P = 0.012) to achieve HBsAg loss.

CONCLUSION

The "nucleos(t)ide analogues-experienced" strategy was more effective than the "De novo" strategy in achieving HBsAg loss for CHB patients. Combination treatment using regimens based on Peg-IFN may be useful to help nucleos(t)ide analogues-treated patients, who have experienced at least 48 weeks of nucleot(s)ide analogue, achieve HBsAg seroclearance.

Sustained Responses in Chronic Hepatitis B Patients with Nucleos(t)ide Analogue Drug-resistance after Peg-interferon Alfa-2a Add-on Treatment: A Long-term Cohort Study

Background and Aims: The use of additional nucleos(t)ide analogues (NAs) without cross-resistance to previously used NAs as a rescue therapy is recommended by most international guidelines for chronic hepatitis B patients with NA-resistance. We aimed to investigate the efficacy and safety of combination therapy of peg-interferon (PegIFN) alfa-2a and NA in these patients, comparing to those who switch to an alternative NA therapy without cross-resistance. Methods: In this prospective, comparative and cohort study, data were collected from the patients' hospital records. Eligible patients were those with hepatitis B e antigen (HBeAg) positivity and resistance to one or more NAs. All patients were treated with alternative NA alone or in combination with PegIFN alfa-2a for 52 weeks or 72 weeks, respectively. HBeAg seroconversion was measured at the end of follow-up (EOF; more than 104 weeks after the end of treatment). Results: Sixty-three patients were recruited to the cohort study (NA-therapy group = 31 patients; combination therapy group of NA and PegIFN alfa-2a = 32 patients). At the EOF, significantly more patients in the combination therapy group (13/27, 48.2%) achieved primary outcome of HBeAg seroconversion than those in the NA therapy group (4/32, 12.5%) (p = 0.003). Four patients (14.8%) in the combination therapy group achieved hepatitis B surface antigen (HBsAg) loss and HBsAg seroconversion, but none in the NA therapy group did (p = 0.039). In the combination therapy group, 16 patients (51.6%) achieved HBeAg seroconversion at the end of treatment, of which, 11 patients (68.8%) maintained the response until EOF. Conclusions: Adding on PegIFN alfa-2a in combination with NA therapy might be an appropriate rescue treatment option for patients who have prior NA resistance. In addition, combination therapy induced sustained off-treatment biochemical responses in these patients.

Current advances in the elimination of hepatitis B in China by 2030

With its 78 million chronic carriers, hepatitis B virus (HBV) infection is still one of the leading public health challenges in China. Over the last two decades, China has made great progress on the prevention of HBV transmission through national vaccination programs. Zero transmission from mother to infant has been proposed as the current goal. Available anti-HBV therapy is efficacious in suppressing HBV replication; however, it fails to completely cure patients with chronic hepatitis B and even requires lifelong treatment. To reduce the costs and improve the efficacy, several trials have been recently conducted in China to optimize the current anti-HBV managements. Novel biomarkers were identified to predict treatment outcomes, and new promising treatment strategies were developed. Reports also indicate that coinfections of HBV with other hepatotropic viruses and human immunodeficiency virus are common in China and cause severe liver diseases, which should be recognized early and treated properly. Work is still needed to eliminate hepatitis B in China by 2030.

Toward a Cure for Hepatitis B Virus Infection: Combination Therapy Involving Viral Suppression and Immune Modulation and Long-term Outcome

Chronic hepatitis B virus (HBV) infection remains a major global health burden. Currently, the approved therapeutic regimens include nucleos(t)ide analogues (NAs) and either interferon or pegylated interferon. NA therapy is generally safe and well tolerated, but the rate of posttreatment virologic relapse is high, making NA treatment a lifetime commitment. The benefits of pegylated interferon treatment include a finite duration, more-durable response and absence of viral resistance. However, sustained response to interferon alone is achieved only in a minority of patients, and side effects are common, which limit its clinical use. Given that HBV covalently closed circular DNA and the integrated HBV genome persist stably in the nuclei of infected hepatocytes, elimination (complete cure) of HBV is rarely achieved. After completion of treatment, sustained HBV surface antigen loss, with or without seroconversion to HBV surface antibody positivity (ie, functional cure), is therefore recommended as the ideal end point for anti-HBV treatment, despite the lack of complete eradication of HBV. Theoretically, combination of antiviral agents with differential mechanisms of actions on HBV, including viral suppression combined with immune modulation (as occurs during treatment with NA plus pegylated interferon), is an encouraging strategy to treat chronic hepatitis B. Recent studies have confirmed certain virological and serological advantages of simultaneous administration of NA and pegylated interferon (de novo combination therapy) or addition of pegylated interferon to ongoing NA therapy (sequential combination therapy) over monotherapy. Few data exist, however, on the long-term outcomes of patients receiving combination therapy. This review summarizes current combination therapy developed to cure chronic HBV infection.

Hepatitis B surface antigen reduction by switching from long-term nucleoside/nucleotide analogue administration to pegylated interferon

Hepatitis B surface antigen (HBsAg) reduction during nucleoside/nucleotide analogue (NA) therapy is slow and an alternative strategy for patients receiving ongoing NA to facilitate HBsAg reduction is required. We investigated whether switching to pegylated interferon (PEG-IFN) after long-term NA administration enhances HBsAg reduction. Forty-nine patients who switched from long-term NA to 48 weeks of PEG-IFN alfa-2a were studied. The mean duration of previous NA was 48 months (sequential group). A total of 147 patients who continued NA and matched for baseline characteristics were analysed for comparison (NA continuation group). The treatment response was defined as HBsAg reduction ≥1.0 logIU/mL at the end of PEG-IFN. HBsAg reduction at week 48 was 0.81±1.1 logIU/mL in the sequential group, which was significantly higher than that in the NA continuation group (0.11±0.3 logIU/mL, P < .001). The treatment response was achieved in 29% and 2% of the sequential group and NA continuation group (P < .001), and the odds ratio of sequential therapy for the treatment response was 19 compared with the NA continuation (P < .001). In patients tested positive for hepatitis B e antigen (HBeAg), HBeAg seroconversion was higher in the sequential group (44% vs 8%, P < .001). In HBeAg-negative patients, only patients in the sequential group achieved HBsAg loss. No patient needed to resume NA administration because of HBV DNA increase accompanied by alanine aminotransferase flares. In summary, sequential therapy with PEG-IFN after long-term NA enhances the reduction of HBsAg and may represent a treatment option to promote HBsAg loss.

The role of peginterferon in nucleos(t)ide-analogue-treated chronic hepatitis B patients: A review of published literature

Chronic hepatitis B infection (CHB) causes up to 1.0 million deaths annually. Currently, more than 90% of CHB patients worldwide are receiving indefinite nucleos(t)ide analogue (NA) therapy. New strategies for optimizing hepatitis B surface antigen (HBsAg) loss are required for NA-treated patients as the majority are unable to achieve HBsAg loss and may require lifelong therapy. In hepatitis B e antigen (HBeAg)-positive patients, switching from NAs to finite peginterferon (PegIFN) therapy can double HBeAg seroconversion rates. One in five patients who switch to PegIFN can achieve HBsAg loss, whereas patients who continue NA therapy typically do not. In HBeAg-negative NA-treated patients, add-on PegIFN therapy achieves higher, albeit modest, HBsAg loss rates compared with continued NA monotherapy and offers the opportunity for NA-treated patients to achieve the inactive carrier state. In the absence of curative therapies, PegIFN represents a valuable, finite option for NA-treated patients who would otherwise require potentially lifelong therapy.

The role of quantitative hepatitis B surface antigen revisited

In the past 10years, there has been a lot of enthusiasm surrounding the use of serum hepatitis B surface antigen (HBsAg) quantification to predict disease activity and monitor treatment response in chronic hepatitis B. The measurement of HBsAg levels have been standardized in IU/ml, and nowadays it is almost a mandatory measurement due to the development of new antiviral treatments aiming at HBsAg seroclearance, i.e., functional cure of hepatitis B. Recently, there has been an improved understanding of the molecular virology of HBsAg, and particularly the relative roles of covalently closed circular DNA and integrated hepatitis B virus (HBV) DNA. This has shed new light on the interpretation of HBsAg levels in different phases of chronic hepatitis B. HBsAg level can assist the differentiation of immune tolerance and immune clearance in hepatitis B e antigen (HBeAg)-positive patients, and it can predict inactive disease and spontaneous HBsAg seroclearance in HBeAg-negative patients. The determination of HBsAg level is pivotal to individualize pegylated interferon (PegIFN) treatment; it is the key investigation to decide early termination of PegIFN among non-responders. Among patients treated by nucleos(t)ide analogues, responders tend to have dramatic reduction of HBsAg to low levels, which may be followed by HBsAg seroclearance. With newer data on combination treatment of PegIFN and nucleos(t)ide analogues as well as emerging new antiviral agents, HBsAg quantification is expected to become increasingly important to monitor and guide antiviral therapy for chronic hepatitis B.

Recent advances in treatment of chronic hepatitis B with entecavir

Entecavir (ETV) is a potent hepatitis B virus inhibitor with a high barrier to resistance, and it has been recommended as one of the first-line drugs for treating chronic hepatitis B (CHB) by guidelines from several international and national societies. This paper reviews the recent advances in the treatment of CHB with ETV, in terms of treatment adherence, efficacy in the treatment of various kinds of patients with CHB, management of patients with partial virological response, viral resistance or treatment failure to ETV, treatment cessation, sequential or combination therapy with ETV and pegylated interferon, as well as the surveillance of hepatocellular carcinoma.

Chronic hepatitis B surface antigen seroclearance-related immune factors

The ultimate aims of the treatment of hepatitis B virus infection are the loss of hepatitis B surface antigen (HBsAg) and hepatitis B surface antibody seroconversion. Unfortunately, these goals are rarely reached. Many factors are associated with HBsAg seroconversion, including genetic, immune, and viral factors. However, the mechanism of HBsAg seroclearance, and particularly the immune mechanism, is still difficult to elucidate. The immune factor interferon-α is currently the main antiviral therapy for chronic hepatitis B virus infection. However, a sustained shift from response of HBsAg to hepatitis B surface antibody seroconversion is rarely obtained. Recent studies have revealed that several of the newly identified immune factors are closely related to the removal of HBsAg. In this article, we review recent studies on these immune factors, their influence on hepatitis B progression, and HBsAg seroconversion.

Review article: the potential of interferon and nucleos(t)ide analogue combination therapy in chronic hepatitis B infection

BACKGROUND

A short-term course of pegylated-interferon (Peg-IFN), or a long-term treatment with a third generation nucleot(s)ide analogue (NUC), of chronic hepatitis B (CHB) infection achieves viral suppression and may prevent disease progression. Owing to different mechanisms of action of the two regimens, a Peg-IFN and NUC combination treatment may be an attractive approach to enhance the off-treatment rates of virological and serological response.

AIM

To review the literature on combinations of Peg-IFN plus NUC, including the simultaneous initiation of Peg-IFN and NUC in naïve patients; an 'add-on' combination, where Peg-IFN is started at variable times after the beginning of NUC; or a 'switch-to' strategy usually from NUC to Peg-IFN.

METHODS

We performed a PubMed literature search using the following terms individually or in combination: NUC, hepatitis B virus, chronic hepatitis, interferon, pegylated-interferon, nucleos(t)ide analogues, entecavir, tenofovir. English-language articles published up to December 2015, as well as conference proceedings from international meetings were reviewed. References from selected papers were reviewed and used if relevant.

RESULTS

While combination and NUC pre-treatment failed to increase HBsAg clearance rates, more promising results were achieved in patients under long-term effective NUC therapy.

CONCLUSION

While Peg-IFN and nucleos(t)ide analogue combination therapy should not be recommended currently, the addition of or the switch to Peg-IFN in nucleos(t)ide analogue-treated patients with chronic hepatitis B infection may be useful option.

Combination or sequential therapy with entecavir and interferon in chronic hepatitis B patients: Current status, problems and prospects

Sixteen years have passed since the initial antiviral treatment of chronic hepatitis B (CHB). Goal of the antiviral treatment is not only to suppress viral replication, but to achieve sustained response after a limited period of treatment and then discontinuation of drugs. Nucleos(t)ide analogues (NAs) and interferons are two types of therapeutic agents with different antiviral mechanisms for treatment of CHB. Monotherapy with NAs or interferons can only achieve ideal goal in a part of CHB patients, and combination and/or sequential therapy with both is an important attempt for CHB treatment in recent years. For patients previously treated with NAs, interferons can be used to replace NAs or in combination with them for a limited period. If interferons do not show good efficacy, then NAs, alone or in combination with interferons, can be used. For patients with high viral load, initial combination therapy may show better efficacy. According to the baseline and response guidelines, the treatment plan should be optimized frequently, and the treatment compliance emphasized with maintenance, medication and examination, along with the administration of chronic diseases, in order to ensure that HBV DNA level is lower than baseline level. For those who have had a continuous drop of HBsAg and HBeAg levels, prolonged treatment or combination of the treatment with dendritic cell (DC) therapy and immunotherapy may achieve more persistent immune control.