Improving clinical outcomes of chronic hepatitis B virus infection

Hepatitis B Virus Infection: A Mini Review

Hepatitis B and C viruses (HBV and HCV) are the leading causes of end-stage liver disease worldwide. Although there is a potent vaccine against HBV, many new infections are recorded annually, especially in poorly resourced places which have lax vaccination policies. Again, as HBV has no cure and chronic infection is lifelong, vaccines cannot help those already infected. Studies to thoroughly understand the HBV biology and pathogenesis are limited, leaving much yet to be understood about the genomic features and their role in establishing and maintaining infection. The current knowledge of the impact on disease progression and response to treatment, especially in hyperendemic regions, is inadequate. This calls for in-depth studies on viral biology, mainly for the purposes of coming up with better management strategies for infected people and more effective preventative measures for others. This information could also point us in the direction of a cure. Here, we discuss the progress made in understanding the genomic basis of viral activities leading to the complex interplay of the virus and the host, which determines the outcome of HBV infection as well as the impact of coinfections.

Current practice and recommendations for management of hepatitis B virus in people living with HIV in Asia

BACKGROUND

The prevalence of HIV and hepatitis B virus (HBV) co-infection is higher in Asia than in Europe and North America and varies significantly between different regions within Asia. Important routes of transmission of both these infections include high-risk unprotected sexual contact, intravenous drug use, and transmission of maternal infection perinatally or in early childhood. While life expectancy among people living with HIV has been extended with effective antiretroviral therapy (ART), HBV-induced liver injury and complications have emerged as a leading cause of morbidity and mortality in people living with HIV.

OBJECTIVES

This article describes the prevalence of co-infection, current clinical practice, and recommendations for the management of people living with HIV-HBV co-infection in Asia.

RESULTS AND CONCLUSIONS

Screening for HBV should occur at the time of HIV diagnosis; however, HBV screening rates in people living with HIV in Asia vary widely by region. Similarly, people with HBV should be screened for HIV before initiation of HBV antiviral therapy. People with HIV-HBV co-infection should be assessed for liver damage and risk factors for liver disease and be monitored regularly for liver complications and HBV DNA. Medical treatment with ART is lifelong and includes tenofovir and lamivudine or emtricitabine, unless intolerant or contraindicated, as these are active against both HIV and HBV. HBV vaccination programmes are effective in reducing co-infection rates. Mother-to-child transmission can be prevented through measures such as vaccination, antenatal screening, and treatment of pregnant women who are infected.

Advancements in the prevention of hepatitis B recurrence by nucleos(t)ide analogue monotherapies after liver transplantation

Previous studies have shown that the recurrence rate of HBV (hepatitis B virus) after liver transplantation (LT) can be as high as 80% without any preventive measures. Therefore, prevention of HBV recurrence after LT is always an essential part of clinical work worldwide. The NAs that have been approved for HBV treatment include lamivudine, adefovir dipivoxil, entecavir (ETV), and telbivudine, tenofovir disoproxil fumarate (TDF), and tenofovir alafenamide (TAF). They are often combined with HBIG to prevent HBV recurrence after LT clinically. However, NAs with a higher genetic barrier, such as ETV, TDF, and TAF, can improve liver function by strongly inhibiting HBV replication and reducing the risks of HBV resistance. Recently, some NAs with a higher genetic barrier, such as ETV, TDF, and TAF, have been adopted as monotherapy for preventing the recurrence of hepatitis B after LT in multiple organ transplant centres and have achieved effective outcomes. This article aims to review the advances for NAs monotherapy in prophylaxis for HBV recurrence after LT.

Serum PIVKA-II and alpha-fetoprotein at virological remission predicts hepatocellular carcinoma in chronic hepatitis B related cirrhosis

BACKGROUND

The risk of hepatocellular carcinoma (HCC) is reduced but not eliminated after nucleos(t)ide analogue (NA) therapy in chronic hepatitis B (CHB). We aimed to investigate the role of serum Prothrombin Induced by Vitamin K Absence or Antagonist-II (PIVKA-II) and alpha-fetoprotein in predicting HCC and mortality in cirrhotic CHB patients at virological remission (VR) following NA therapy.

METHODS

Patients with CHB-related cirrhosis undergoing NA therapy from two medical centers in Taiwan were retrospectively included. Serum PIVKA-II were quantified by an automated chemiluminescence assay. Multivariable Cox proportional hazards regression models were used to identify predictors for HCC and death. Serial on-treatment PIVKA-II levels after VR were investigated.

RESULTS

Overall, 293 CHB-related cirrhosis patients were included. At VR, the mean age was 55, and the mean PIVKA-II level was 35 mAU/mL. After a mean follow-up of 78 months, 76 patients developed HCC and 19 died. After adjustment for confounding factors, alpha-fetoprotein >7 ng/mL (hazard ratio [HR]: 2.84, 95% confidence interval [CI]: 1.73-4.67) and PIVKA-II >50 mAU/mL (HR: 2.46, 95%CI: 1.35-4.49) at VR significantly predicted HCC development. In patients with alpha-fetoprotein ≤10 ng/mL or ≤20 ng/mL at VR, PIVKA-II >50 mAU/mL increased 2.45 or 3.16-fold risk of HCC, respectively. PIVKA-II levels after VR increased serially in patients who developed HCC afterwards.

CONCLUSIONS

In patients with CHB-related cirrhosis, serum alpha-fetoprotein >7 ng/mL and PIVKA-II >50 mAU/mL at the time of antiviral therapy-induced VR is associated with a greater risk of HCC. PIVKA-II is a predictive marker for HCC in patients with low normal alpha-fetoprotein level.

Residual HBV DNA and pgRNA viraemia is associated with hepatocellular carcinoma in chronic hepatitis B patients on antiviral therapy

BACKGROUND

We aimed to assess whether residual hepatitis B virus (HBV) viraemia is associated with HCC development.

METHODS

This is a case-control study of 104 patients [52 HCC and 52 non-HCC (matched with age, gender, cirrhosis and treatment duration)] on ≥ 3 years entecavir (ETV) with unquantifiable HBV DNA by Cobas Taqman assay v2.0 (Roche Diagnostics; lower limit of quantification [LLOQ] 20 IU/mL). Serial sera within 1, 1-2, and > 2 years prior to HCC diagnosis or last follow-up (LFU) were measured for HBV DNA and pre-genomic (pg) RNA using a highly sensitive semi-quantitative PCR assay with lower limit of detection of 10 IU/mL and LLOQ of 51.5 IU/mL, respectively.

RESULTS

Among the 104 patients (80.8% male, median age 61.2 years old, 38.5% cirrhosis, median duration of ETV 45.5 months), 38.5% and 9.6% HCC patients had undetectable serum DNA and pgRNA, respectively, compared to 65.4% and 36.5% in non-HCC patients; P = 0.005 & 0.001, respectively, at the time of HCC diagnosis/LFU. Detectable HBV DNA and pgRNA were associated with a higher 2-year risk of HCC development (HR 2.79, 95% CI 1.424-5.468 & HR 4.544, 95% CI 1.07-19.289, respectively). No significant differences were observed for qHBsAg levels between HCC and non-HCC patients.

CONCLUSIONS

More than 50% CHB patients on ETV with HBV DNA < LLOQ by standard assay had persistent viraemia as determined by a more sensitive assay. Detectable HBV DNA or pgRNA by more sensitive assays was associated with HCC development. More potent viral suppression is required to further reduce the risk of HCC.

Hepatitis B: Immunization and Impact on Natural History and Cancer Incidence

Enhancing host immunity by vaccination to prevent hepatitis B virus (HBV) infection remains the most important strategy for global control of hepatitis B. Currently, 187 countries have in place infant hepatitis B vaccination programs. Hepatitis B surface antigen prevalence has decreased to less than 1% in children after successful implementation of universal HBV vaccination in newborns. The incidence of primary liver cancer in children, adolescents, and young adults has drastically decreased to near zero in birth cohorts receiving hepatitis B vaccination. Elimination of chronic hepatitis B by 2030 is not a mission impossible.

Anti-PD-1 blockade with nivolumab with and without therapeutic vaccination for virally suppressed chronic hepatitis B: A pilot study

BACKGROUND & AIMS

To evaluate the hypothesis that increasing T cell frequency and activity may provide durable control of hepatitis B virus (HBV), we administered nivolumab, a programmed death receptor 1 (PD-1) inhibitor, with or without GS-4774, an HBV therapeutic vaccine, in virally suppressed patients with HBV e antigen (HBeAg)-negative chronic HBV.

METHODS

In a phase Ib study, patients received either a single dose of nivolumab at 0.1 mg/kg (n = 2) or 0.3 mg/kg (n = 12), or 40 yeast units of GS-4774 at baseline and week 4 and 0.3 mg/kg of nivolumab at week 4 (n = 10). The primary efficacy endpoint was mean change in HBV surface antigen (HBsAg) 12 weeks after nivolumab. Safety and immunologic changes were assessed through week 24.

RESULTS

There were no grade 3 or 4 adverse events or serious adverse events. All assessed patients retained T cell PD-1 receptor occupancy 6-12 weeks post-infusion, with a mean total across 0.1 and 0.3 mg/kg cohorts of 76% (95% CI 75-77), and no significant differences were observed between cohorts (p = 0.839). Patients receiving 0.3 mg/kg nivolumab without and with GS-4774 had mean declines of -0.30 (95% CI -0.46 to -0.14) and -0.16 (95% CI -0.33 to 0.01) log₁₀ IU/ml, respectively. Patients showed significant HBsAg declines from baseline (p = 0.035) with 3 patients experiencing declines of >0.5 log₁₀ by the end of study. One patient, whose HBsAg went from baseline 1,173 IU/ml to undetectable at week 20, experienced an alanine aminotransferase flare (grade 3) at week 4 that resolved by week 8 and was accompanied by a significant increase in peripheral HBsAg-specific T cells at week 24.

CONCLUSIONS

In virally suppressed HBeAg-negative patients, checkpoint blockade was well-tolerated and led to HBsAg decline in most patients and sustained HBsAg loss in 1 patient.

LAY SUMMARY

Chronic hepatitis B virus infection (CHB) is characterized by a dysfunctional immune response. In patients with CHB, inhibitory receptors, such as programmed death receptor 1 (PD-1) are overexpressed on T cells, leading to an ineffective immune response in the liver. Herein, we show that the PD-1 inhibitor, nivolumab, is safe and effective for the treatment of virally suppressed patients with CHB. Australian New Zealand Clinical Trials Registry (http://www.anzctr.org.au/) number: ACTRN12615001133527.

Serum Mac-2-binding protein glycosylation isomer and risk of hepatocellular carcinoma in entecavir-treated chronic hepatitis B patients

BACKGROUND AND AIM

Hepatocellular carcinoma (HCC) can still develop in chronic hepatitis B (CHB) patients receiving antiviral treatment. Serum Mac-2-binding protein glycosylation isomer (M2BPGi) is a novel marker for liver fibrosis. We investigated its role on incidence of HCC in entecavir (ETV)-treated CHB patients.

METHODS

We identified HCC cases diagnosed at ≥ 1 year of ETV treatment. CHB patients without HCC (matched for age, gender, baseline hepatitis B virus-DNA, and duration of ETV treatment) were identified in approximately 1:2 ratio (HCC: non-HCC) for comparison. Serum samples were retrieved at baseline (initiation of ETV), 3, and 5 years of ETV for serum M2BPGi measurement (expressed in cut-off index [COI]).

RESULTS

One hundred HCC cases were matched with 185 CHB patients without HCC (median age 56.7 years, 78.9% male, baseline hepatitis B virus-DNA 5.6 logIU/mL, and median follow-up 7.1 years). Median time from ETV initiation to incident HCC was 3.9 years. Serum M2BPGi levels were significantly higher in HCC cases compared with controls at baseline and year 3 (1.25 vs 0.98 [P = 0.004], 0.89 vs 0.74 [P = 0.018] COI, respectively). Multivariate analysis showed that baseline M2BPGi was the only independent factor associated with incident HCC (odds ratio 1.241, 95% confidence interval 1.039-1.482, P = 0.017). Using a cut-off value of 1.15 COI, the sensitivity, specificity, positive predictive value, and negative predictive value of baseline serum M2BPGi in cirrhotic patients to predict incident HCC were 90%, 53.8%, 69.6%, and 82.1%, respectively.

CONCLUSIONS

Baseline and 3-year serum M2BPGi may be useful to identify high risk patients on antiviral treatment for subsequent HCC development.

Taiwan consensus statement on the management of chronic hepatitis B

The experts of Taiwan Association for the Study of Liver (TASL) have actively participated and led the guidelines on hepatitis B virus (HBV) management by Asian Pacific Association for the Study of Liver (APASL) which is the first international association for the study of liver to publish the statement on HBV management before. However, there are more and more new data on the natural history and treatment of HBV infection in the past decade. These include new application of an old biomarker (quantitative HBsAg), clinical significance of HBV genotype and naturally occurring mutations, the role of non-invasive examination in evaluating severity of hepatic fibrosis, clinical significance of outcome calculators, new drug or new combination strategies towards more effective therapy and organ transplantation including liver and non-liver transplantation. It is time to publish the guidelines on HBV management of Taiwan. Hence, TASL have conducted an expert meeting to review, to discuss and to debate the relevant literatures, followed by draft the manuscript of HBV management guidelines and recommendations. The guidelines include general management, indications for fibrosis assessment, time to start or stop drug therapy, choice of drug to initiate therapy, when and how to monitor the patients during and after stopping drug therapy. Recommendations on the therapy of patients in special circumstances, including women in childbearing age, patients with antiviral drug resistance, concurrent viral infection, hepatic decompensation, patient receiving immune suppression or chemotherapy and patients in the setting of liver transplantation and hepatocellular carcinoma, are also included.

Combination Therapy for Chronic Hepatitis B: Current Updates and Perspectives

Nucleos(t)ide analogues (NUCs) and interferon have been used for several decades to treat chronic hepatitis B; however, the therapeutic response remains unsatisfactory. Although NUC therapy exhibits potent on-treatment viral suppression, frequent off-therapy virological relapses suggest an indefinite treatment course. Interferon modulates the innate and adaptive antiviral immune responses and thus increases the chance of viral eradication. Interferon therapy has the advantage of a finite duration, absence of drug resistance, and durable posttreatment responses. Therefore, the combination of NUCs and interferon can theoretically facilitate a synergistic therapeutic effect. This paper summarizes the current strategies of various combination therapies into three categories: the simultaneous “dual” strategy, sequential combination “add-on” strategy, and “switch” strategy. Generally, dual therapy exhibits greater on-treatment and off-therapy viral suppression and lower drug resistance compared with NUC monotherapy. Compared with interferon monotherapy, dual therapy has greater on-treatment viral suppression but shows no difference in off-therapy sustained virological responses. Specific add-on or switch strategies provide promising on-treatment efficacy in select patients. Pretreatment or on-treatment quantitative hepatitis B surface antigen and e antigen are predictive for the treatment efficacy of combination therapy. The optimal schedule of combination regimens and individualized therapy remain to be comprehensively evaluated.

Unmet Needs in Clinical and Basic Hepatitis B Virus Research

Chronic hepatitis B (CHB) has become a treatable and controllable disease. The current nucleos(t)ide analogue (NUC) and pegylated interferon therapies effectively help slow disease progression and reduce the risk of cirrhosis, hepatocellular carcinoma (HCC), and CHB-associated mortality. Long-term viral suppression is easily achievable by NUC therapy, with limited adverse reactions. However, several unmet requirements still exist, including safety and risk-stratified HCC surveillance among patients who received long-term NUC therapy. Criteria for determining which patients should receive finite-duration NUC therapy and which should receive combination therapy with both NUC and pegylated interferon remain unsettled. The management of hepatitis B virus (HBV) e antigen-positive viremic patients with normal liver function and the incorporation of new biomarkers to help manage CHB require further exploration. To achieve functional cure (ie, HBV surface antigen seroclearance) and complete cure (ie, eradication of covalently closed circular DNA) of CHB, several challenges in basic research must be addressed, including the development of an efficient cell culture system and animal models for HBV investigation, development of treatment to eradicate covalently closed circular HBV DNA, and development of immunotherapy for CHB. This brief review focuses on unmet needs in both clinical and basic HBV research.

Src-homology protein tyrosine phosphatase-1 agonist, SC-43, reduces liver fibrosis

This study aimed to investigate the role of src-homology protein tyrosine phosphatase-1 (SHP-1)–signal transducer and activator of transcription 3 (STAT3) pathway in liver fibrogenesis and the anti-fibrotic effect of SHP-1 agonist. The antifibrotic activity of SC-43, a sorafenib derivative with an enhanced SHP-1 activity, was evaluated in two fibrosis mouse models by carbon tetrachloride induction and bile duct ligation. Rat, human, and primary mouse hepatic stellate cells (HSCs) were used for mechanistic investigations. The results showed that SHP-1 protein primarily localized in fibrotic areas of human and mouse livers. SC-43 treatment reduced the activated HSCs and thus effectively prevented and regressed liver fibrosis in both fibrosis mouse models and improved mouse survival. In vitro studies revealed that SC-43 promoted HSC apoptosis, increased the SHP-1 activity and inhibited phospho-STAT3. The enhanced SHP-1 activity in HSCs significantly inhibited HSC proliferation, whereas SHP-1 inhibition rescued SC-43-induced HSC apoptosis. Furthermore, SC-43 interacted with the N-SH2 domain of SHP-1 to enhance the activity of SHP-1 as its antifibrotic mechanism. In conclusion, the SHP-1–STAT3 pathway is crucial in fibrogenesis. SC-43 significantly ameliorates liver fibrosis through SHP-1 upregulation. A SHP-1-targeted antifibrotic therapy may represent a druggable strategy for antifibrotic drug discovery.

Elimination of Hepatitis B: Is It a Mission Possible?

Chronic hepatitis B virus (HBV) infection is a global public health issue. Although the disease cannot be cured effectively, disease management has been improved over the past decade. The introduction of potent nucleos(t)ide analogues (NAs) to suppress viral replication represented a giant leap in the control of this disease. It has been shown that tenofovir treatment, a potent NA, complements current immunoprophylaxis to diminish mother-to-infant transmission in pregnant women with a high viral load. For patients with chronic HBV infection, quantitative hepatitis B surface antigen is a useful tool to define inactive carriers and to guide antiviral therapy. Quantification of HBV mutants is also useful in predicting long-term outcomes more precisely than ever. The next challenge is how to achieve an HBV cure; although immunotherapy is a promising strategy, the current results from two clinical trials using therapeutic vaccines to induce HBV-specific immune response in patients with chronic HBV infection are disappointing. In the coming years, we are expecting to see a combination of therapeutic agents with various modes of action to complete the mission of HBV elimination.

Benefits of long-term therapy with nucleos(t)ide analogues in treatment-naïve patients with chronic hepatitis B

OBJECTIVE

To assess the benefits of long-term nucleos(t)ide analogue (NA) therapy in reducing the severity and progression of liver disease in treatment-naïve patients with chronic hepatitis B (CHB).

SCOPE

As complications of CHB, such as hepatic decompensation and hepatocellular carcinoma (HCC), take a long time to develop in patients with less advanced disease, the long-term benefits of NA therapy in such patients are more difficult to prove than short- or medium-term benefits. Thus, the recent literature was reviewed to evaluate the impact of NA therapy on the long-term outcomes of treatment-naïve CHB patients.

METHODS

A literature search of the MEDLINE/PubMed database was undertaken to identify studies published since 2010 of the long-term use of NAs with high potency and low drug resistance profiles in treatment-naïve CHB patients. A total of 22 studies were identified, many of which were retrospective analyses or case-control studies, as well as three meta-analyses and one systematic review.

RESULTS

Analysis of the retrieved studies showed that long-term NA therapy in treatment-naïve CHB patients did prevent or delay the occurrence of complications, including hepatic decompensation, HCC, and liver-related death, in comparison with no treatment. However, it did not completely eliminate the risk of these complications, particularly in those with cirrhosis. Although long-term NA therapy improved the clinical status of patients with decompensated cirrhosis, the risk of cirrhotic complications including HCC, liver transplantation, and liver-related mortality remained significant in comparison with those with compensated cirrhosis.

CONCLUSIONS

Long-term administration is generally advised in all CHB patients treated with NAs because of the high rates of virological and clinical relapse after stopping therapy. The findings of this analysis lend support to the choice of highly potent agents with a low drug resistance profile to maximize viral suppression in CHB patients and halt or delay progression to end-stage liver disease.

HBeAg Seroconversion in HBeAg-Positive Chronic Hepatitis B Patients Receiving Long-Term Nucleos(t)ide Analog Treatment: A Systematic Review and Network Meta-Analysis

BACKGROUND

HBeAg seroconversion is an important intermediate outcome in HBeAg-positive chronic hepatitis B (CHB) patients. This study aimed to compare the effect of nucleos(t)ide analogs (NAs) on HBeAg seroconversion in treating CHB with lamivudine, adefovir, telbivudine, entecavir, and tenofovir.

METHODS

Network meta-analysis of NA treatment-induced HBeAg seroconversion after 1-2 years of treatment was performed. In addition, NA treatment-induced HBeAg seroconversion after 3-5 years of treatment was systematically evaluated.

RESULTS

A total of 31 articles were included in this study. Nine and five studies respectively reporting on 1- and 2-year treatment were included in our network meta-analysis. In addition, 6, 5, and 5 studies, respectively reporting on 3-, 4-, and 5-year treatment were included in our systematic evaluation. Telbivudine showed a significantly higher HBeAg seroconversion rate after a 1 year treatment period compared to the other NAs (odds ratio (OR) = 3.99, 95% CI 0.68-23.6). This was followed by tenofovir (OR = 3.36, 95% CI 0.70-16.75). Telbivudine also showed a higher seroconversion rate compared to the other NAs after a 2 year treatment period, (OR = 1.38, 95% CI 0.92-2.22). This was followed by entecavir (OR = 1.14, 95% CI 0.72-1.72). No significant difference was observed between spontaneous induction and long-term telbivudine treatment-induced HBeAg seroconversion. However, entecavir and tenofovir treatment-induced HBeAg seroconversions were significantly lower than spontaneous seroconversion.

CONCLUSION

Long-term treatment with potent anti-HBV drugs, especially tenofovir and entecavir, may reduce HBeAg seroconversion compared with spontaneous HBeAg seroconversion rate. Telbivudine treatment, whether short term or long term, is associated with higher HBeAg seroconversion compared with the other NAs. However, the high rates of drug resistance likely limit the application of telbivudine.

Four-year entecavir therapy reduces hepatocellular carcinoma, cirrhotic events and mortality in chronic hepatitis B patients

BACKGROUND & AIMS

Oral antiviral therapy may reduce the disease progression of chronic hepatitis B (CHB) patients. We aimed to further investigate the efficacy of long-term entecavir therapy in reduction of the risk of hepatocellular carcinoma (HCC), cirrhotic events and mortality in a large group of CHB-related cirrhosis patients.

METHODS

The C-TEAM (Cirrhosis-Taiwanese EntecAvir Multicenter) study was a nationwide, multicenter, retrospective-prospective cohort study in Taiwan. We enrolled treatment-naïve patients with CHB-related cirrhosis and baseline HBV-DNA≥2000 IU/mL receiving long-term entecavir therapy and compared the development of HCC, cirrhotic events and mortality with that of a historical untreated cohort.

RESULTS

In total, 1315 entecavir-treated and 503 untreated patients with cirrhosis were enrolled, with median treatment and follow-up durations of 4 and 6 years respectively. Compared with the untreated cohort, entecavir therapy was associated with a 60% HCC risk reduction [hazard ratio (HR): 0.40, 95% confidence interval (CI): 0.28-0.57]. Additionally, an older age, the male gender, HBeAg positivity, alpha-fetoprotein (AFP)≥7 ng/mL before therapy were independent predictors of HCC development. Further analysis showed that entecavir therapy significantly reduced risks of variceal bleeding, spontaneous bacterial peritonitis, and liver-related and all-cause mortality. These findings were confirmed by propensity score-matched cohorts in sensitivity analysis. In patients under entecavir therapy, an older age, the male gender, HBeAg positivity, AFP level ≥7 ng/mL before therapy, and 1-year virological response were predictive of HCC development.

CONCLUSIONS

Four-year entecavir therapy significantly reduces the risk of HCC, cirrhotic events and mortality in patients with CHB-related cirrhosis.

Prevention of Hepatocellular Carcinoma

The epidemiology of hepatocellular carcinoma (HCC) has significantly changed throughout the past decade and will continue to do so in the future as a consequence of effective primary prevention and treatment of virus-related liver diseases. However, other risk factors for HCC are constantly on the rise, including alcoholic liver disease and nonalcoholic fatty liver disease. The knowledge on these and further risk factors associated with an increased risk of HCC provide the opportunity and chance for the development and implementation of successful preventive strategies to decrease the worldwide burden of HCC. This mini-review gives a short overview on current strategies in primary, secondary, and tertiary prevention of HCC.

Hepatitis B vaccination and prevention of hepatocellular carcinoma

Hepatitis B virus (HBV) infection is a global health threat; with 240 million people are chronic carriers of the virus. The infection can cause acute and chronic liver disease including liver cirrhosis and hepatocellular carcinoma (HCC). On the basis of disease burden and the availability of safe and effective vaccines, World Health Organization has recommended that hepatitis B vaccine be incorporated into routine infant and childhood immunization programs for all countries. The efficacy of universal immunization has been proven in many countries, with substantial reductions of the prevalence of HBV carriage in children, adolescents and young adults. Most important, hepatitis B vaccination can protect them from HCC, as has been demonstrated in Taiwan and other countries. Nevertheless, the implementation of worldwide vaccination against HBV indeed requires more effort to overcome the social and economic challenges. To have a global control of HBV infection, we have to continue the universal HBV vaccination, interrupt the possible transmission routes and treat eligible patients with antiviral agents. However, current treatments are still far from ideal as they cannot eradicate intrahepatic HBV cccDNA, and lifelong administration of these agents will pose a major economic burden, especially in the endemic Asia-Pacific region. Thus we need innovative treatment strategies and novel agents with difference modes of action to overcome the unmet medical need for an efficient HBV cure with subsequent global eradication of HBV infection, hopefully by the first half of 21st century.

Viral hepatitis. HBV cure--can we pin our hopes on immunotherapy?

Therapeutic vaccines are considered to be able to reverse the dysfunctional immune state of chronic hepatitis B and thus hold the promise for HBV cure. Martin et al. developed a novel adenovirus-based therapeutic vaccine TG1050 and demonstrated its induction of long-lasting antiviral CD8+ T-cell immunity in mouse models of HBV persistence.