Hepatitis B vaccines: assessment of the seroprotective efficacy of two recombinant DNA vaccines

Prevalence of vaccine-derived hepatitis B surface antibodies in children and adolescents in Germany: results from a population-based survey, 2014-2017

INTRODUCTION

Childhood vaccination against hepatitis B has been recommended in Germany since 1995. WHO defines a primary vaccination series as successful if the initial hepatitis B surface antibody (anti-HBs) level is ≥ 10 IU/L directly after vaccination. Anti-HBs levels vary depending on the number of doses, type of vaccine, and time interval between the last two doses. In 2021, Germany began to recommend three instead of four doses of polyvalent hepatitis-B-containing vaccines. Our aim was to estimate the proportion of vaccinated children in Germany with anti-HBs levels < 10 IU/L, 10-99 IU/L, and ≥ 100 IU/L by number and type of vaccine, and assess if number of doses and compliance with recommended time interval between the last two doses are associated with an anti-HBs level ≥ 10 IU/L when considering type of vaccine and time since last dose.

METHODS

We used data from a national cross-sectional study (2014-2017) of children (3-17 years). We excluded participants with unknown vaccination dates, unreadable or incomplete vaccination cards, and hepatitis B virus (HBV)-positive participants. We defined a recommended schedule as a vaccination series with at least six months between the two last doses and having three doses or more. We calculated weighted anti-HBs sero-prevalence for three anti-HBs levels: < 10 IU/L, 10-99 IU/L and ≥ 100 IU/L. We fitted two logistic regression models to examine the relationship between number of doses and recommended schedule on anti-HBs levels (≥ 10 IU/L and ≥ 100 IU/L) considering time since last dose and type of vaccine (Infanrix, Hexavac, Monovalent).

RESULTS

We included 2,489 participants. The weighted proportion of vaccinated children per anti-HBs level was < 10 IU/L: 36.3% [95%CI 34.0-38.7%], 10-99 IU/L: 35.7% [33.2-38.2%] and ≥ 100 IU/L: 28.0% [25.9-30.2%]. We did not find an association between a recommended schedule of three versus four doses and anti-HBs ≥ 10 IU/L or ≥ 100 IU/L.

CONCLUSIONS

Anti-HBs levels in later childhood were about equal, whether children received three or four doses. This implies that the change in the recommendations does not affect the anti-HBs level among children in Germany. Future studies are needed on the association of anti-HBs levels and adequate sustained protection against HBV.

Hybrid large hepatitis B surface protein composed of two viral genotypes C and D induces strongly cross-neutralizing antibodies

Hepatitis B virus (HBV) vaccination is known to effectively decrease the risk of HBV infection. However, several issues need to be addressed in order to develop an improved HBV vaccine. Although the HBV vaccine has been shown to be effective, this vaccine needs to be more efficacious in defined groups, including non-responders (i.e., individuals who do not develop a protective response even after vaccination) and in health care workers and travelers who require rapid protection. Furthermore, it has been reported that universal HBV vaccination has accelerated the appearance of vaccine-escape mutants resulting from the accumulation of mutations altering the "a" determinant of the hepatitis B surface (HBs) protein. To address these problems, we have been focusing on the large HBs (LHBs) protein, which consists of three domains: pre-S1, pre-S2, and S (in N- to C-terminal order). To enhance the immunogenicity of LHBs, we developed a yeast-derived hybrid LHBs (hy-LHBs) antigen composed of the LHBs proteins from two distinct genotypes (Genotypes C and D). The levels of antibodies induced by hy-LHBs immunization were high not only against S, but also against the pre-S1 and pre-S2 domains. Additionally, hy-LHBs immunization induced significantly more strongly cross-reactive neutralizing antibodies than did small HBs (SHBs) or LHBs of any genotype alone. These findings suggested that hy-LHBs might serve as a candidate antigen for use in an improved prophylactic HBV vaccine.

Impaired humoral immune response to hepatitis B vaccine in patients on maintenance hemodialysis

Hepatitis B virus (HBV) infection is a worldwide health problem. We aimed in this study to investigate the humoral immune response derived to HBV vaccine following completing the vaccine series in Madinah. Two hundred and two Saudi hemodialysis (HD) patients were included in this cross-sectional study. Mean concentration of Hepatitis B surface antibody (anti-HBs) was significantly higher among patients who received the vaccination twice compared to patients who received the vaccination only after starting hemodialysis (252 ± 489 mIU/mL vs. 144 ± 327 mIU/mL, respectively, p = 0.008). Almost half of the study sample were non-protected and showed anti-HBs concentration < 10 mlU/mL. In contrast, 20.3% (n = 41) were identified as poor responders (10-100 mlU/mL) and only 28.2% (n = 57) were identified as good responders (10-100 mlU/mL). However, the latter two groups were accounted as protected (48.5%, n = 98). Patients sex was associated with anti-HBs concentration (non-responders; poor responders; good responders), where significantly higher proportion of good responders were females compared to males (p = 0.007). In conclusion, HBV vaccine is efficient to elicit humoral immune response in hemodialysis patients.

Hepatitis B virus-induced hepatocellular carcinoma: a persistent global problem

Hepatitis B virus (HBV) infections are highly prevalent globally, representing a serious public health problem. The diverse modes of transmission and the burden of the chronic carrier population pose challenges to the effective management of HBV. Vaccination is the most effective preventive measure available in the current scenario. Still, HBV is one of the significant health issues in various parts of the globe due to non-response to vaccines, the high number of concealed carriers, and the lack of access and awareness. Universal vaccination programs must be scaled up in neonates, especially in the developing parts of the world, to prevent new HBV infections. Novel treatments like combinational therapy, gene silencing, and new antivirals must be available for effective management. The prolonged infection of HBV, direct and indirect, can promote the growth of hepatocellular carcinoma (HCC). The present review emphasizes the problems and probable solutions for better managing HBV infections, causal risk factors of HCC, and mechanisms of HCC.

[Viral Hepatitis in Patients with Inflammatory Bowel Disease]

There has been a rise in the incidence of inflammatory bowel disease (IBD) in developing countries, including South Korea. Consequently, the use of immunosuppressive agents such as immunomodulators or biologics has also increased. Due to immunosuppression, patients on these agents are at increased risk of various opportunistic infections during treatment, which may sometimes lead to serious adverse outcomes. Viral hepatitis, especially hepatitis B, is one of the infectious conditions that can be reactivated during immunosuppressive therapy, and adequate strategies for monitoring and prophylaxis are needed to prevent it. South Korea is one of the countries with intermediate endemicity for hepatitis A and B. Thus, taking adequate precautions against viral hepatitis could prevent new infections or reactivation of these conditions in patients with IBD on immunosuppressive therapy. In this review article, we have summarized the latest evidence on viral hepatitis in patients with IBD that would be of assistance in clinical practice.

Modelling the prevalence of hepatitis B towards eliminating it as a major public health threat in China

BACKGROUND

The World Health Organization (WHO) requires reduction in the prevalence of hepatitis B virus (HBV) surface antigen (HBsAg) in children to 0.1% by 2030, a key indicator for eliminating viral hepatitis as a major public health threat. Whether and how China can achieve this target remains unknown, although great achievements have been made. We aimed to predict the decline of HBsAg prevalence in China and identify key developments needed to achieve the target.

METHODS

An age- and time-dependent dynamic compartmental model was constructed based on the natural history of HBV infection and the national history and current status of hepatitis B control. The model was run from 2006 to 2040 to predict the decline of HBsAg prevalence under three scenarios including maintaining current interventions (status quo), status quo + peripartum antiviral prophylaxis (PAP, recommended by WHO in 2020), and scaling up current interventions + PAP.

RESULTS

Under the status quo, HBsAg prevalence would decrease steadily in all age groups, but the WHO's target of 0.1% prevalence in children aged < 5 years would not be achieved until 2037. The results are robust according to sensitivity analyses. Under the status quo + PAP, the HBsAg prevalence of children aged < 5 years would significantly decrease with the introduction of PAP, and the higher the successful interruption coverage is achieved by PAP, the more significant the decline. However, even if the successful interruption coverage reaches 90% by 2030, the 0.1% prevalence target would not be met until 2031. Under the scaling up current interventions + PAP, combined with scale-up of current interventions, the WHO's 0.1% target would be achieved on time or one year in advance if PAP is introduced and the successful interruption coverage is scaled up to 80% or 90% by 2030, respectively.

CONCLUSIONS

It is difficult for China to achieve the WHO's target of 0.1% HBsAg prevalence in children by 2030 by maintaining current interventions. PAP may play an important role to shorten the time to achieve the target. A comprehensive scale-up of available interventions including PAP will ensure that China achieves the target on schedule.

Association between history of HBV vaccine response and anti-SARS-CoV-2 spike antibody response to the BioNTech/Pfizer's BNT162b2 mRNA SARS-CoV-2 vaccine among healthcare workers in Japan: A prospective observational study

INTRODUCTION

Inadequate vaccine response is a common concern among healthcare workers at the frontlines of the COVID-19 pandemic. We aimed to investigate if healthcare workers with history of weak immune response to HBV vaccination are more likely to have weak responses against the BioNTech/Pfizer's BNT162b2 mRNA SARS-CoV-2 vaccine.

METHODS

We prospectively tested 954 healthcare workers for the Anti-SARS-CoV-2 spike (S) protein antibody titers prior to the first and second BNT162b2 vaccination doses and after four weeks after the second dose using Roche's Elecsys® assay. We calculated the percentage of patients who seroconverted after the first and second doses. We estimated the relative risk of non-seroconversion after the first BNT162b2 vaccine (defined as anti-SARS-CoV-2-S titer <15 U/mL) among HBV vaccine non-responders (HBs-Ab titer <10 mIU/mL) and weak responders (≥10 and <100 mIU/mL) compared to normal responders (≥100 mIU/mL).

RESULTS

Among 954 healthcare workers recruited between March 9 and March 24, 2021 at Osaka Medical and Pharmaceutical University, weak and normal HBV vaccine responders had comparable S-protein titers after the first BNT162b2 dose (51.4 [95% confidence interval 25.2-137.0] versus 59.7 [29.8-138.0] U/mL, respectively). HBV vaccine non-responders were more likely than normal responders to not seroconvert after a single dose (age and sex-adjusted relative risk 1.85 95% confidence interval [1.10-3.13]) although nearly all participants seroconverted after the second dose. After limiting the analysis to 382 patients with baseline comorbidity data, the comorbidity-adjusted relative risk of non-seroconversion among HBV vaccine non-responders to normal responders was 1.32 (95% confidence interval [0.59-2.98]).

DISCUSSION

Long term follow-up studies are needed to understand if protective immunity against SARS-CoV-2 wanes faster among those with history of HBV vaccine non-response and when booster doses are warranted for these healthcare workers.

Duration of Hepatitis B Vaccine-Induced Protection among Medical Students and Healthcare Workers following Primary Vaccination in Infancy and Rate of Immunity Decline

Since the introduction of hepatitis B virus (HBV) vaccines, the numbers of HBV infections and complications have significantly decreased. However, the evidence on whether primary vaccination of infants confers lifelong immunity varies. We aimed to assess long-term immunity among healthcare workers and medical students, and the rate of decline of HBV surface antigen antibodies (anti-HBs). Hepatitis B status among participants born after 1 January 1992 was reviewed at Chulabhorn Royal Academy, Thailand. Participants were stratified by intervals since primary vaccination. HBV immunity was determined and analyzed as anti-HBs decline rate in participants with multiple follow-ups. A total of 464 participants were analyzed, with a median age of 23. Protective immunity against HBV (anti-HBs ≥ 10 mIU/mL) at 16–20, 21–25 and 26–28 years post-primary vaccination was 28%, 51.7% and 60%, respectively. The overall declining rate of anti-HBs was −42.39 mIU/mL per year. Participants with anti-HBs levels of >100–1000 mIU/mL at baseline had a faster decline rate than those with anti-HBs levels of 10–100 mIU/mL. Primary vaccination may not provide lifelong protection since HBV immunity deteriorates over time. Individuals with higher initial HBV immunity levels may experience a faster decline rate.

[Hepatitis B virus infection and vaccine-induced immunity: the role of sociodemographic determinants : Results of the study "German Health Interview and Examination Survey for Adults" (DEGS1, 2008-2011)]

Hintergrund und Ziel

Trotz niedriger Prävalenz der Hepatitis-B-Virus-(HBV-)Infektion in Deutschland ist es wichtig, vulnerable Gruppen und Ansatzpunkte für die Prävention zu identifizieren. In ersten Analysen der „Studie zur Gesundheit Erwachsener in Deutschland“ (DEGS1, 2008–2011) waren HBV-Infektion und -Impfung mit sozidemografischen Determinanten assoziiert. In dieser Arbeit werden die Ergebnisse im Detail untersucht.

Material und Methoden

In DEGS1 lag für 7046 Teilnehmende (Alter: 18–79 Jahre) eine HBV-Serologie vor. Die stattgehabte HBV-Infektion war durch Antikörper gegen das Hepatitis-B-Core-Antigen (Anti-HBc) definiert, die impfinduzierte Immunität durch alleinigen Nachweis von Antikörpern gegen das Hepatitis-B-Surface-Antigen (Anti-HBs). Seroprävalenzen von HBV-Infektions- und -Impfstatus wurden geschlechtsstratifiziert geschätzt und Assoziationen mit Alter, Gemeindegröße, Einkommen, formaler Bildung, Krankenversicherung und Migrationsgeneration in logistischen Regressionen analysiert.

Ergebnisse

Die HBV-Infektion war bei Männern und Frauen unabhängig mit den Altersgruppen 34–64 und ≥ 65 Jahre, erster Migrationsgeneration und Leben in größeren Gemeinden assoziiert, zudem bei Männern mit niedrigem Einkommen und bei Frauen mit niedriger Bildung. Die impfinduzierte Immunität war bei Männern und Frauen unabhängig mit den Altersgruppen 18–33 und 34–64 Jahre, mittlerer und hoher Bildung und hohem Einkommen assoziiert, darüber hinaus bei Männern mit mittlerem Einkommen und privater Krankenversicherung und bei Frauen mit fehlendem Migrationshintergrund.

Diskussion

Die Berücksichtigung von Migrationsstatus, Einkommen und Bildung könnte zur zielgenauen Ausrichtung der HBV-Prävention beitragen.

Zusatzmaterial online

Zusätzliche Informationen sind in der Online-Version dieses Artikels (10.1007/s00103-021-03473-z) enthalten.

Immunogenicity and Safety of a 3-Antigen Hepatitis B Vaccine vs a Single-Antigen Hepatitis B Vaccine: A Phase 3 Randomized Clinical Trial

IMPORTANCE

There is a need for improved immunogenicity of hepatitis B virus (HBV) vaccines among young adults with risk of infection.

OBJECTIVES

To demonstrate manufacturing equivalence of a 3-antigen (3A) HBV vaccine, evaluate noninferiority of seroprotection rate (SPR) of 3A-HBV vs single-antigen (1A) HBV after 2 and 3 vaccine doses, and compare safety and reactogenicity between 3A-HBV and 1A-HBV vaccines.

DESIGN, SETTING, AND PARTICIPANTS

This phase 3, double-blinded, randomized clinical trial included healthy adults aged 18 to 45 years randomized to 1 of three 3A-HBV groups or 1 control group receiving 1A-HBV. The trial was conducted at 37 community clinics and academic hospitals in Canada, Europe, the United Kingdom, and the United States between December 2017 and October 2019. Participants were followed up for 48 weeks after the first vaccination.

INTERVENTIONS

Intramuscular administration of 3A-HBV (10 μg) or 1A-HBV (20 μg) on days 0, 28, and 168.

MAIN OUTCOMES AND MEASURES

Geometric mean concentration (GMC) of serum hepatitis B surface antibodies (anti-HBs) and proportion of participants achieving seroprotection.

RESULTS

Of 2838 participants, 1638 (57.8%) were women, 2595 (91.5%) were White, and 161 (5.7%) were Black or African American. A total of 712 participants (25.1%) were randomized to the 1A-HBV group and 2126 (74.9%) to 3A-HBV. The mean (SD) age at informed consent was 33.5 (8.0) years. The study demonstrated 3A-HBV lot-to-lot consistency, as the 2-sided 95% CIs for each pairwise comparison for the anti-HBs GMC ratios were within 0.67 and 1.50 (eg, adjusted GMC ratio, lot A vs lot B: 0.82; 95% CI, 0.67-1.00; lot A vs lot C: 0.95; 95% CI, 0.78-1.15; lot B vs lot C: 1.16; 95% CI, 0.95-1.41). The SPR of the pooled 3A-HBV was noninferior to 1A-HBV and higher than 1A-HBV after 2 vaccinations at day 168 (90.4% [95% CI, 89.0%-91.8%] vs 51.6% [95% CI, 47.5%-55.6%]) and 3 vaccinations at day 196 (99.3% [95% CI, 98.7%-99.6%] vs 94.8% [95% CI, 92.7%-96.4%]). The mean GMC of anti-HBs with 3A-HBV was 7.9 times higher after 2 vaccinations at day 168 and 3.5 times higher after 3 vaccinations at day 196 compared with 1A-HBV (after 2 vaccinations, 3A-HBV: GMC, 118.7 mIU/mL; 95% CI, 108.0-129.0 mIU/mL; SE, 1.0 mIU/mL; 1A-HBV: GMC, 15.0 mIU/mL; 95% CI, 12.9-17.5 mIU/mL; SE, 1.0 mIU/mL; after 3 vaccinations, 3A-HBV: GMC, 5442.4 mIU/mL; 95% CI, 4967.0-5963.0 mIU/mL; SE, 1.0 mIU/mL; 1A-HBV: 1567.2 mIU/mL; 95% CI, 1338.0-1834.0 mIU/mL; SE, 1.0 mIU/mL). Rates of local and systemic reactogenicities were higher with 3A-HBV compared with 1A-HBV (local: 1805 of 2124 [85.0%] vs 469 of 712 [65.9%]; systemic: 1445 [68.0%] vs 428 [60.1%]). Vaccine discontinuation due to adverse events (AE) was uncommon, and serious AEs were infrequent, reported in 42 participants (2.0%) and 3 participants (0.4%) in the 3A-HBV and 1A-HBV groups, respectively.

CONCLUSIONS AND RELEVANCE

In this study, consistently higher antibody concentrations and SPRs were found with 3A-HBV after 2 and 3 doses vs 1A-HBV in adults aged 18 to 45 years old. The safety and efficacy of 3A-HBV shows its usefulness for the prevention of hepatitis B in young healthy adults.

TRIAL REGISTRATION

Clinicaltrials.gov Identifier: NCT03408730; EU Clinical Trials Number: 2017-001820-22.

Preventing hepatitis B virus infection among healthcare professionals: potential impact of a 2-dose versus 3-dose vaccine

The exposure risk to the highly infectious hepatitis B virus (HBV) is an established and recognizable hazard to healthcare professionals (HCPs). In the United States, implementing preemptive vaccination programs and safety procedures resulted in drastic reductions in HBV infections among HCPs; however, many HCPs remain unprotected and risk of exposure persists, especially among those first entering a healthcare system and undergoing professional training. First-generation HBV vaccines require completion of a 3-dose schedule over a 6-month interval for maximum immunogenicity. By comparison, HepB-CpG (HEPLISAV-B®) is a 2-dose HBV vaccine licensed in the United States in 2017, inducing rapid seroprotection over a 1-month interval and may represent a more effective strategy for combating HBV infection in US healthcare systems. In this modeling study, the health and economic impact of implementing an HBV vaccination strategy with HepB-CpG versus the 3-dose HBV vaccine (Engerix-B®) was evaluated among HCPs newly entering a healthcare system. The model used effective seroprotection rate, a real-world metric accounting for HCP vaccine compliance and seroprotection rates for different dosing regimens and considered current pricing for postexposure prophylaxis treatment. Compared with the 3-dose vaccine, HepB-CpG was anticipated to provide faster, increased protection against HBV infection among newly entered HCPs. In protecting a greater percentage of HCPs, HepB-CpG was also projected to substantially reduce the risk of HBV exposure. Accordingly, an economic analysis showed HepB-CpG vaccination would reduce costs of postexposure prophylaxis treatment compared with the 3-dose vaccine. Overall, HepB-CpG represents an effective therapeutic strategy against HBV infection for US healthcare systems.

Hepatitis B vaccination response of treatment-naive patients with juvenile idiopathic arthritis

To evaluate the vaccine response of treatment-naive juvenile idiopathic arthritis (JIA) patients who were fully vaccinated against Hepatitis B Virus (HBV) and then compare their antibody status with healthy controls. In this multicenter study, initial visit hepatitis B surface antigen (HbsAg) and anti-hepatitis B surface antibody (anti-Hbs) titers of 262 treatment-naive JIA patients who were followed up regularly between May 2015 and October 2019 were evaluated retrospectively from patients' medical records and compared with 276 healthy peers. Both HbsAg and anti-Hbs antibody titers were tested by the ELISA technique. Anti-HBs titers ≥ 10 IU/L were considered as reactive indicating seroprotection against HBV. In the JIA group, seropositivity rate was 59.1% while 72.9% of the control group were immune against HBV (p = 0.002). The median titer for anti-Hbs was 14 (range: 0-1000) IU/L in the patient group and 43.3 (range: 0-1000) IU/L in the control group (p = 0.01). Neither JIA patients nor healthy controls were positive for HbsAg. Patients with JIA vaccinated according to the national vaccination schedule were evaluated at their first visit in pediatric rheumatology outpatient clinics for anti-Hbs presence and it was found that they have lesser seroprotectivity than their age and sex-matched routinely vaccinated, healthy peers. So, to complete missing vaccines and booster vaccine doses, assessing the immune status of the patients at the time of diagnosis against HBV should be in the check-list of physicians dealing with pediatric rheumatic diseases.

Efficacy and Safety of a 3-Antigen (Pre-S1/Pre-S2/S) Hepatitis B Vaccine: Results of a Phase 3 randomized clinical trial in the Russian Federation

Background

This study compares the immunogenicity and safety of a 3-antigen (S/pre-S1/pre-S2) hepatitis B (HepB) vaccine (3AV), to a single antigen vaccine (1AV) in adults to support the registration of 3AV in Russia.

Methods

We conducted a randomized, double-blind, comparative study of 3-dose regimens of 3AV (10 μg) and 1AV (20 µg) in adults aged 18–45 years. We evaluated immunogenicity based on hepatitis B surface (HBs) antibody titers at days 1, 28, 90, 180, and 210, adverse and serious adverse events (SAEs) to study day 210. The primary outcome was based on the difference in rates of seroconversion at day 210 (lower bound 95% confidence interval [CI]: > − 4%). Secondary outcomes were seroprotection rates (SPR), defined as anti-HBs ≥10 mIU/mL and anti-HBs geometric mean concentration (GMC).

Results

Rate of seroconversion in 3AV (100%) was noninferior to 1AV (97.9%) at study day 210 (difference: 2.1%, 95% CI: −2.0, 6.3%]) but significantly higher at study day 28. SPR at study day 210 was >97% in both arms. Anti-HBs titers were significantly higher at study days 90 (P = .001) and 180 (P = .0001) with 3AV. Sex, age, and body mass index (BMI) had no impact on anti-HBs titers. The rates of local reactions related to vaccination were similar between vaccine arms (3AV vs 1AV) after the first (30% vs 18.8%, P = .15), second (20.0% vs 14.6%, P = .33), and third vaccination (14.9% vs 23.4%, P = .22). No SAEs were reported.

Conclusions

3AV was noninferior to 1AV. 3AV induced high SPR, and there were no safety concerns.

Clinical Trials Registration. NCT04209400.

Cross-Protection of Hepatitis B Vaccination among Different Genotypes

Hepatitis B (HB) vaccination is the most effective method for preventing HB virus (HBV) infection. Universal HB vaccination containing recombinant HB surface antigens (HBsAg) is recommended. Our data revealed that human monoclonal HB surface antibody (anti-HBs) from individuals inoculated with genotype C-based HB vaccine induced cross-protection against HBV genotype A infection. An in vitro infection model demonstrated anti-HBs-positive sera from individuals inoculated with genotype A- or C-based HB vaccine harbored polyclonal anti-HBs that could bind to non-vaccinated genotype HBV. However, because there were low titers of anti-HBs specific for HBsAg of non-vaccinated genotype, high anti-HBs titers would be required to prevent non-vaccinated genotype HBV infection. Clinically, the 2015 Centers for Disease Control and Prevention guidelines state that periodic monitoring of anti-HBs levels after routine HB vaccination is not needed and that booster doses of HB vaccine are not recommended. However, the American Red Cross suggests that HB-vaccine-induced immune memory might be limited; although HB vaccination can prevent clinical liver injury (hepatitis), subclinical HBV infections of non-vaccinated genotypes resulting in detectable HB core antibody could not be completely prevented. Therefore, monitoring anti-HBs levels after routine vaccination might be necessary for certain subjects in high-risk groups.

Immunological Analysis of the Hepatitis B Virus "a" Determinant Displayed on Chimeric Virus-Like Particles of Macrobrachium rosenbergii Nodavirus Capsid Protein Produced in Sf9 Cells

Chimeric virus-like particles (VLPs) have been widely exploited for various purposes including their use as vaccine candidates, particularly due to their ability to induce stronger immune responses than VLPs consisting of single viral proteins. In the present study, VLPs of the Macrobrachium rosenbergii nodavirus (MrNV) capsid protein (Nc) displaying the hepatitis B virus “a” determinant (aD) were produced in Spodoptera frugiperda (Sf9) insect cells. BALB/c mice immunised with the purified chimeric Nc-aD VLPs elicited a sustained titre of anti-aD antibody, which was significantly higher than that elicited by a commercially available hepatitis B vaccine and Escherichia coli-produced Nc-aD VLPs. Immunophenotyping showed that the Sf9-produced Nc-aD VLPs induced proliferation of cytotoxic T-lymphocytes and NK1.1 natural killer cells. Furthermore, enzyme-linked immunospot (ELISPOT)analysis showed the presence of antibody-secreting memory B cells in the mice splenocytes stimulated with the synthetic aD peptide. The significant humoral, natural killer cell and memory B cell immune responses induced by the Sf9-produced Nc-aD VLPs suggest that they present good prospects for use as a hepatitis B vaccine candidate.

Prevention and management of viral hepatitis in inflammatory bowel disease: a clinical practice guideline by the Korean Association for the Study of Intestinal Diseases

The treatment of inflammatory bowel disease (IBD) has been revolutionized for the last 10 years by the increasing use of immunomodulators and biologics. With immunosuppression of this kind, opportunistic infection is an important safety concern for patients with IBD. In particular, viral hepatitis is determined by the interaction between the virus and the host's immunity, and the risk of reactivation increases if immunity is compromised by immunosuppression therapy. Parts of Asia, including Korea, still show intermediate endemicity for the hepatitis A virus and hepatitis B virus compared with the United States and Western Europe. Thus, members of IBD research group of the Korean Association for the Study of Intestinal Diseases have produced a guideline on the prevention and management of viral hepatitis in IBD.

Hepatitis B Virus (HBV) Subviral Particles as Protective Vaccines and Vaccine Platforms

Hepatitis B remains one of the major global health problems more than 40 years after the identification of human hepatitis B virus (HBV) as the causative agent. A critical turning point in combating this virus was the development of a preventative vaccine composed of the HBV surface (envelope) protein (HBsAg) to reduce the risk of new infections. The isolation of HBsAg sub-viral particles (SVPs) from the blood of asymptomatic HBV carriers as antigens for the first-generation vaccines, followed by the development of recombinant HBsAg SVPs produced in yeast as the antigenic components of the second-generation vaccines, represent landmark advancements in biotechnology and medicine. The ability of the HBsAg SVPs to accept and present foreign antigenic sequences provides the basis of a chimeric particulate delivery platform, and resulted in the development of a vaccine against malaria (RTS,S/AS01, Mosquirix^TM), and various preclinical vaccine candidates to overcome infectious diseases for which there are no effective vaccines. Biomedical modifications of the HBsAg subunits allowed the identification of strategies to enhance the HBsAg SVP immunogenicity to build potent vaccines for preventative and possibly therapeutic applications. The review provides an overview of the formation and assembly of the HBsAg SVPs and highlights the utilization of the particles in key effective vaccines.

Serological response to three alternative series of hepatitis B revaccination (Fendrix, Twinrix, and HBVaxPro-40) in healthy non-responders: a multicentre, open-label, randomised, controlled, superiority trial

BACKGROUND

Serological non-response can be present after hepatitis B vaccination in healthy adults. We aimed to establish which of three revaccination regimens is most effective at inducing protective immunity METHODS: Healthy adults (aged 18-80 years) from 16 Dutch centres (13 public health services, two university hospitals, and one travel clinic) were included in this multicentre, parallel group, randomised, controlled, superiority trial. The inclusion criterion was vaccine non-response (hepatitis B surface antibody [anti-HBs] titre <10 IU/L) after a primary series with three doses of one type of recombinant vaccine against hepatitis B virus (either HBVaxPro-10 or Engerix-B at months 0, 1, and 6). Participants were individually randomly assigned (1:1:1:1) to a vaccination series of repeated initial vaccination (HBVaxPro 10 μg or Engerix-B 20 μg) as the control, or to Twinrix 20 μg, Fendrix 20 μg, or HBVaxPro 40 μg. We used a web-based randomisation programme, stratified by centre, with a block size of four. Participants and centres were unmasked to assignment after randomisation. Laboratory staff and investigators were masked to vaccine-group assignment. All revaccination schedules were identical, with intramuscular vaccinations at 0, 1, and 2 months. Anti-HBs was measured at 0, 1, 2, and 3 months. The primary outcome was the percentage of responders (anti-HBs titres ≥10 IU/L) at 3 months. Immunogenicity and safety analyses were based on an intention-to-vaccinate analysis, the immunogenicity analysis with last observation carried forward for missing data, and the Bonferroni and the Benjamini-Hochberg method were applied to correct for multiple testing. The trial was registered in the Dutch National Trial Register and inclusion has been stopped (identifier NL3011; EudraCT-number 2011-005627-40).

FINDINGS

The participants were recruited between Nov 1, 2012, and Sept 1, 2017. 480 participants were randomly assigned and included in intention-to-vaccinate analyses: 124 (26%) to control, 118 (25%) to Twinrix, 114 (24%) to HBVaxPro-40, and 124 (26%) to Fendrix. At month 3 the percentage of responders was 83 (67%) of 124 (95% CI 57·9-75·1 in the control group, 94 (80%) of the 118 (71·3-86·5) in the Twinrix group, 95 (83%) of 114 (75·2-89·7) in the HBVaxPro-40 group, and 108 (87%) of 124 (79·9-92·4) in the Fendrix group. Compared with the control group, the percentage of responders was superior for the HBVaxPro-40 group (adjusted difference 21·6% [95% CI 10·4-32·7], p=0·0204 [Bonferroni corrected p value]) and the Fendrix group (26·3% [15·4-37·3], p=0·0006), but not the Twinrix group (25·0% [13·0-37·0]; p=0·0846). One serious adverse event occurred (herpes zoster ophthalmicus) in the Fendrix group, which was not attributed to the vaccine.

INTERPRETATION

Revaccinating healthy non-responders with Fendrix or HBVaxPro-40 resulted in significantly higher proportions of responders and therefore indication for these vaccines should be expanded to enable revaccination of non-responders.

FUNDING

National Institute for Public Health and the Environment.

Glucopyranosyl lipid adjuvant enhances immune response to Ebola virus-like particle vaccine in mice

The identification of adjuvants that promote lasting antigen-specific immunity and augment vaccine efficacy are integral to the development of new protein-based vaccines. The Ebola virus-like particle (VLP) vaccine expressing Ebola virus glycoprotein (GP) and matrix protein (VP40) was used in this study to evaluate the ability of TLR4 agonist glucopyranosyl lipid adjuvant (GLA) formulated in a stable emulsion (SE) to enhance immunogenicity and promote durable protection against mouse-adapted Ebola virus (ma-EBOV). Antibody responses and Ebola-specific T cell responses were evaluated post vaccination. Survival analysis after lethal ma-EBOV challenge was performed 4 weeks and 22 weeks following final vaccination. GLA-SE enhanced EBOV-specific immunity and resulted in long-term protection against challenge with ma-EBOV infection in a mouse model. Specifically, GLA-SE elicited Th1-skewed antibodies and promoted the generation of EBOV GP-specific polyfunctional T cells. These results provide further support for the utility of TLR4 activating GLA-SE-adjuvanted vaccines.

Updates on vaccinating the inflammatory bowel disease patient

Many of the therapeutic options for patients with inflammatory bowel disease (IBD) suppress the immune system, which increases the risk of certain infections in these patients. Effective vaccines exist and offer protection against a number of infectious diseases. However, data has shown that IBD patients are inadequately vaccinated and, as a result, are at risk of developing certain preventable infections. Furthermore, gastroenterologists' knowledge regarding the appropriate immunizations to administer to their IBD patients is suboptimal. Areas covered: Over the past several years, there has been a considerable amount of research contributing to our knowledge regarding vaccination of patients with IBD. Expert opinion: This updated review article focuses on the current immunization schedule for the IBD patient and stresses the important role of the gastroenterologist as an active participant in the health maintenance of their IBD patients.

Response to hepatitis B vaccination in patients with inflammatory bowel disease: a prospective observational study in Korea

Background/Aims

Testing for hepatitis B virus (HBV) serologic markers and appropriate vaccination are required in the management of inflammatory bowel disease (IBD) patients. We evaluated immunogenicity for HBV in IBD patients and the response to the HBV vaccination.

Methods

From May 2014 to August 2016, patients diagnosed with IBD were prospectively included and evaluated for antibody to hepatitis B surface antigen, antibody to hepatitis B core antigen, and antibody to hepatitis B surface antigen. Among the 73 patients who were confirmed with nonimmunity to HBV, 44 patients who had completed the 3-dose HBV vaccination series received a single booster vaccination, while 29 patients who had not completed the vaccinations series or were unsure of receiving the vaccination received a full vaccination series.

Results

An optimal response was obtained in 70.5% of the patients in the booster group, and 89.7% of the patients in the full vaccination group. Age younger than 26 years (odds ratio [OR], 6.01; 95% confidence interval [CI], 1.15–31.32; P=0.033) and a complete previous vaccination series (OR, 0.15; 95% CI, 0.03–0.80; P=0.026) were associated with optimal vaccine response. Previous complete vaccination series (OR, 0.11; 95% CI, 0.02–0.73; P=0.022) was the only predictive factor for lower compliance.

Conclusions

The response to the HBV vaccination was lower in patients older than 26 years and for those patients with a complete vaccination history. Since patients with a complete vaccination history also had poor compliance, serum HBV-titers should be checked more thoroughly, and a full vaccination series should be administered in cases when there is a negative response to the booster vaccination.

Hepatitis B Vaccination Effective in Children Exposed to Anti-Tumour Necrosis Factor Alpha in Utero

INTRODUCTION

Neonates exposed to tumour necrosis factor [TNF] alpha inhibitors in utero are born with detectable drug levels which can still be detected throughout the first year of life. Since 2011, the hepatitis B virus [HBV] vaccine is routinely administered to all newborns in the Netherlands. Adults treated with anti-TNF have been reported to respond inadequately to the HBV vaccine. The aim of this study was to compare anti-HB levels in anti-TNF-exposed children with non-exposed children following routine Dutch HBV vaccination.

METHODS

We performed a cross-sectional, controlled cohort study from 2014 to 2017 in a single, tertiary referral centre. Pregnant women treated with anti-TNF for inflammatory bowel disease [IBD] and their subsequent children were recruited from the IBD preconception outpatient clinic. Pregnant women not treated with anti-TNF for IBD and their subsequent children were eligible as controls. Adherence to the Dutch National Vaccination Programme was mandatory for participation in this study. A venous blood sample was obtained 1 month after final HBV vaccination. Anti-HB levels were measured by enzyme-linked immunosorbent assay.

RESULTS

Anti-HB levels at 12 months did not differ between the anti-TNF-exposed [n = 15] and the control group [n = 12] [> 1000 IU/l vs > 1000 IU/l, p = 0.59]. All children were successfully immunized against HBV, defined as anti-HB > 10 IU/l. Median anti-TNF levels determined in cord blood at birth were 9.0 µg/ml [interquartile range: 3.0-15.0 µg/ml] for infliximab and 0.4. µg/ml [interquartile range: 0.3-0.6 µg/ml] for adalimumab. There were no differences in general birth and health outcomes.

CONCLUSION

Children born with detectable anti-TNF levels can be effectively vaccinated against HBV.

Impaired Immune Response to Primary but Not to Booster Vaccination Against Hepatitis B in Older Adults

Many current vaccines are less immunogenic and less effective in elderly compared to younger adults due to age-related changes of the immune system. Most vaccines utilized in the elderly contain antigens, which the target population has had previous contact with due to previous vaccination or infection. Therefore, most studies investigating vaccine-induced immune responses in the elderly do not analyze responses to neo-antigens but rather booster responses. However, age-related differences in the immune response could differentially affect primary versus recall responses. We therefore investigated the impact of age on primary and recall antibody responses following hepatitis B vaccination in young and older adults. Focused gene expression profiling was performed before and 1 day after the vaccination in order to identify gene signatures predicting antibody responses. Young (20-40 years; n = 24) and elderly (>60 years; n = 17) healthy volunteers received either a primary series (no prior vaccination) or a single booster shot (documented primary vaccination more than 10 years ago). Antibody titers were determined at days 0, 7, and 28, as well as 6 months after the vaccination. After primary vaccination, antibody responses were lower and delayed in the elderly compared to young adults. Non-responders after the three-dose primary series were only observed in the elderly group. Maximum antibody concentrations after booster vaccination were similar in both age groups. Focused gene expression profiling identified 29 transcripts that correlated with age at baseline and clustered in a network centered around type I interferons and pro-inflammatory cytokines. In addition, smaller 8- and 6-gene signatures were identified at baseline that associated with vaccine responsiveness during primary and booster vaccination, respectively. When evaluating the kinetic changes in gene expression profiles before and after primary vaccination, a 33-gene signature, dominated by IFN-signaling, pro-inflammatory cytokines, inflammasome components, and immune cell subset markers, was uncovered that was associated with vaccine responsiveness. By contrast, no such transcripts were identified during booster vaccination. Our results document that primary differs from booster vaccination in old age, in regard to antibody responses as well as at the level of gene signatures.

Clinical Trial Registration

www.clinicaltrialsregister.eu, this trial was registered at the EU Clinical Trial Register (EU-CTR) with the EUDRACT-Nr. 2013-002589-38.

Antibody Response to Hepatitis B Virus Vaccine is Impaired in Patients With Inflammatory Bowel Disease on Infliximab Therapy

BACKGROUND

Studies have demonstrated an association between anti-TNF/immunomodulator agents used in inflammatory bowel disease (IBD) and impaired hepatitis B virus (HBV) vaccine immunogenicity, but little data exist on whether specific medication types affect protective HBsAb titers. Our aim was to analyze this association.

METHODS

This is a retrospective cohort study. Inclusion criteria: age ≥18, diagnosis of Crohn's disease (CD) or ulcerative colitis (UC), previous HBV vaccination series and/or ≥1 positive HBsAb, and record of IBD therapy in 6 months before titer level. Patients were stratified based upon medication exposures: anti-TNF, immunomodulator, combination anti-TNF and immunomodulatory, and a reference arm. Titer levels following vaccination and specific medication types given in the 6 months before titer were recorded. Seroprotection was defined as HBsAb ≥10 IU/l and ≥100 IU/l.

RESULTS

The study cohort (N = 391) was 70.8% white, 51.4% female and 64.2% had CD and 35.8% had UC. The mean age was 45.8 years. A significantly lower percentage of patients exposed to anti-TNF, immunomodulator or dual therapy had titers ≥10 (P < 0.01). Regarding specific medications, only patients exposed to infliximab (P < 0.01) were less likely to have titer levels ≥10, after controlling for other medication exposures, age at titer level, and interval time between vaccination/titer level. This was not found for patients exposed to adalimumab, methotrexate, 6-mercaptopurine, or azathioprine.

CONCLUSIONS

Patients exposed to infliximab were significantly less likely to have protective HBsAb titer levels following vaccination, a trend not seen in patients on adalimumab. Efforts to vaccinate IBD patients against HBV before use of immunomodulators and anti-TNFs, infliximab specifically, and screen periodically thereafter must be reinforced.

A Prospective Study of Humoral and Cellular Immune Responses to Hepatitis B Vaccination in Habitual Marijuana Smokers

Exposure to Δ⁹-tetrahydrocannabinol (THC) in vitro and in animal models can significantly impair the differentiation, activation and function of dendritic cells, T cells and B cells. However, studies directly assessing the impact of marijuana smoking on human immunity are lacking. A prospective study of immune responses to a standard hepatitis B vaccination was therefore carried out in a matched cohort of 9 marijuana smokers (MS) and 9 nonsmokers (NS). In addition to their regular marijuana use, MS smoked four marijuana cigarettes in a monitored setting on the day of each vaccination. Blood samples were collected over time to assess the development of hepatitis B-specific immunity. The majority of subjects from both the NS (8) and MS (6) groups developed positive hepatitis B surface antibody titers (>10 IU/L) and of these 6 NS and 5 MS were classified as high antibody (good) responders (>100 IU/L). The development of a good response correlated with the presence of hepatitis B-specific T cell proliferation and cytokine production, resulting in a clear distinction regarding the immune status of good responders versus non-responders. However, even though there were slighter more non-responders in the MS cohort, there were no significant differences between MS and NS with respect to peripheral blood cell phenotypes or vaccination-related changes in hepatitis B responses. While a larger cohort may be required to rule out a small suppressive effect, our findings do not suggest that habitual marijuana smoking exerts a major impact on the development of systemic immunity to hepatitis B vaccination.

Incidence of Low Seroimmunity to Hepatitis B Virus in Children With Inflammatory Bowel Disease

OBJECTIVES

Patients with inflammatory bowel disease (IBD) often receive immunosuppressive therapy, which may make them vulnerable to infections such as hepatitis B. We hypothesized that hepatitis B virus titers are low in the vaccinated pediatric population with IBD. The aims of our study were to identify the incidence of lower titers of hepatitis B surface antibody (HBsAb) and determine which patient factors may be associated with lower HBsAb titers.

METHODS

Patients with diagnosis of IBD, ages 5 to 18 years, were prospectively enrolled. Patients were confirmed to have had a full series of hepatitis B vaccination. Quantitative serum HBsAb titers were measured and logistic regression analysis with independent variables of age, sex, race, disease phenotype, surgery, medications and a dependent variable of adequate HBsAb titers (> 10 mIU/mL) was performed.

RESULTS

Of the 116 patients enrolled, 57 were boys and 59 were girls. 75 patients had a diagnosis of Crohn disease; 32 had a diagnosis of ulcerative colitis; and 9 patients had been diagnosed as having indeterminate colitis. At the time of the study, 15 patients were taking corticosteroid, 66 on an immunomodulator, and 53 on a biologic. Sixty percent of patients in the 5- to 10-year age group had protective titers versus 22% to 27% in the older groups, P = 0.04. Only 28% of the 116 patients had HBsAb titers of >10m IU/mL. Twenty percent of the patients taking corticosteroids, 27% taking immunomodulators, and 24% taking biologics were found to be seroimmune.

CONCLUSIONS

Nearly two-thirds of pediatric patients with IBD have low titers against hepatitis B virus. Titers were highest in the younger patients. No patient-specific variable, such as the use of immunosuppressants, appeared to influence these low titers.

INTERCHANGEABILITY OF VIRAL VACCINES FOR IMMUNIZATION

The review presents the results of the analysis of domestic and foreign scientific literature on the interchangeability of hepatitis A, B and influenza vaccines. The WHO materials, regulatory documents, data from scientific literature of foreign countries and Russia about the vaccine interchangeability are summarized. The problem of objective assessment of interchangeability of drugs is relevant worldwide. The definition of an "interchangeable drug" does not draw a clear line between the interoperability criteria for chemical and immunobiological drugs. The official guidance documents on immunization adopted in several countries define "interchangeability" as the practice of transition from a vaccine available from a certain manufacturer to a similar vaccine available from another manufacturer. The term "interchangeable" can be applied to immunobiological drugs if one of the drugs can be replaced with the other in the course of vaccination. The concept of interchangeability applies to vaccines that do not differ in efficacy (immunological, preventive, epidemiological) and safety and are used in an immunization course involving multiple administration of these vaccines. The definition of interchangeability is important in order to address the problem of replacing unidirectional vaccines available from different manufacturers when purchasing vaccines included in the national schedule of preventive vaccinations and in the schedule of preventive vaccination on epidemic indications. One of the most important conditions for "interchangeability" of vaccines is their application in accordance with the recommended schedule of administration and the dosage indicated by the manufacturer. Research data show that vaccines can be interchangeable if used in accordance with the recommended schedule of administration and the dosage specified by the manufacturer. Control agencies of many countries issue recommendations regulating the procedure of vaccine replacement in case of necessity. However, there are no special regulations of vaccine interchangeability in Russia. The concept of vaccine "interchangeability" should be extended to the continuation of a course of vaccinations in a particular person with a vaccine of another manufacturer and the possibility of applying similar vaccines available from different manufacturers.

Decreased Hepatitis B vaccine response in pediatric patients with atopic dermatitis, psoriasis, and morphea

Multiple groups of patients have been recognized for having high rates of non-responders to the Hepatitis B vaccine including those with HIV, inflammatory bowel disease, and chronic kidney disease. These patients are at increased risk for infection due to both the nature of their underlying diseases and the immunosuppressive drugs they are commonly prescribed. Identification of groups with high non-response rates is essential in order to establish vaccination guidelines and prevent serious infections in already susceptible patients. We thus aimed to assess the rate of antibody response to the HBV vaccine in patients with psoriasis, atopic dermatitis, or morphea prior to starting immunosuppressive therapy.

ACG Clinical Guideline: Preventive Care in Inflammatory Bowel Disease

Recent data suggest that inflammatory bowel disease (IBD) patients do not receive preventive services at the same rate as general medical patients. Patients with IBD often consider their gastroenterologist to be the primary provider of care. To improve the care delivered to IBD patients, health maintenance issues need to be co-managed by both the gastroenterologist and primary care team. Gastroenterologists need to explicitly inform the primary care provider of the unique needs of the IBD patient, especially those on immunomodulators and biologics or being considered for such therapy. In particular, documentation of up to date vaccinations are crucial as IBD patients are often treated with long-term immune-suppressive therapies and may be at increased risk for infections, many of which are preventable with vaccinations. Health maintenance issues addressed in this guideline include identification, safety and appropriate timing of vaccinations, screening for osteoporosis, cervical cancer, melanoma and non-melanoma skin cancer as well as identification of depression and anxiety and smoking cessation. To accomplish these health maintenance goals, coordination between the primary care provider, gastroenterology team and other specialists is necessary.

Stable emulsion (SE) alone is an effective adjuvant for a recombinant, baculovirus-expressed H5 influenza vaccine in healthy adults: A Phase 2 trial

BACKGROUND

Influenza A viruses of the H5 subtype have been identified as important targets for development of vaccines. Achievement of potentially protective antibody responses against pandemic strains has usually required the use of adjuvants.

OBJECTIVES

We evaluated a candidate A/Indonesia/05/2005 (H5) vaccine generated by baculovirus expression of recombinant hemagglutinin (HA) protein with or without stable emulsion (SE) as an adjuvant.

METHODS

Healthy subjects 18-49years old were randomized (1:1:1:1) to receive two doses of rHA at 7.5ug per dose (no adjuvant), or 3.8ug, 7.5ug, or 15ug per dose formulated with 2% SE separated by 21days, and serum from day 0, 21, 42, and 201 assessed by hemagglutination-inhibition.

RESULTS

341 subjects were enrolled in the study and 321 received two doses of vaccine. Vaccination was well tolerated in all groups. After two doses, seroconversion was noted in only 9% (95% confidence interval 4%, 17%) of recipients of unadjuvanted vaccine at 7.5ug, but in 70% (59%, 80%), 76% (65%, 85%), and 83% (73%, 91%) of those receiving adjuvanted vaccine at 3.8ug, 7.5ug, or 15ug respectively.

CONCLUSIONS

Stable emulsion alone is an effective adjuvant for rH5 vaccine in healthy adults. All three adjuvanted dose groups met the current criterion for seroconversion rate for pandemic vaccines. This dose-ranging study also identified a group (15ug per dose formulated with 2% SE) that met the criteria for both seroconversion and percentage of subjects achieving an HI antibody titer⩾40. These Phase 2 data support the further clinical development of SE adjuvanted Panblok H5.

CLINICAL TRIAL REGISTRATION

NCT01612000. The protocol was approved by the relevant Institutional Review Board for each study site, and the study was conducted in accordance with the Declaration of Helsinki, International Conference of Harmonisation - Good Clinical Practice, and all applicable laws and regulations. All participants provided written informed consent before study procedures.

Vaccination against hepatitis B virus among people who inject drugs - A 20year experience from a Swedish needle exchange program

BACKGROUND

People who inject drugs (PWID) are at particular risk of hepatitis B virus (HBV) acquisition, but often have poor access or adherence to HBV vaccination. Vaccination against HBV has been offered at a major Swedish needle exchange program (NEP) since 1994. The aim of this study was to evaluate vaccine completion and response rates, and the effect of sequential booster doses to non-responders to the standard vaccination schedule.

METHODS

PWID enrolled in the NEP 1994-2013, without serological markers for HBV at baseline (negative for HBsAg/anti-HBc/anti-HBs), were offered a three-dose standard intramuscular vaccination schedule (Engerix®-B, GSK, 20μg/mL, intended to be received at months 0, 1 and 6). Vaccination response was defined as protective levels of anti-HBs (⩾10mIU/mL). Up to three booster doses were then offered for non-responders, each followed by anti-HBs testing.

RESULTS

HBV data was available for 2352 identifiable individuals at NEP enrolment, of whom 1516 (64.5%) had no markers for previous HBV exposure or vaccination. Vaccination was initiated for 1142 (75.3%) individuals and 898 (59.2%) completed the standard vaccination schedule. Post-vaccination anti-HBs levels were available from 800 individuals, with 598 (74.8%) responding to the basic vaccination schedule. After up to three booster doses a total of 676 (84.5%) individuals achieved protective anti-HBs levels. Non-response to vaccination was associated with higher age and anti-HCV positivity (p<0.001). Eighteen incident cases of HBV infection were observed among vaccine non-responders, as well as 30 cases among those who had not completed vaccination.

CONCLUSION

We demonstrate the feasibility of including HBV vaccination in the services offered by a NEP, with completion of vaccination in a majority of HBV-susceptible PWID. The response to HBV vaccination among PWID was relatively low; however, the addition of up to three booster doses improved the response rate from 74.8 to 84.5%.

Suitable hepatitis B vaccine for adult immunization in China

The aim of this study was to evaluate, in adults, the immunogenicity of six hepatitis B vaccines with different doses or different manufacturers in the Chinese market and to provide evidence to support adult hepatitis B vaccination. Participants were randomly divided into six groups (I–VI). Six vaccines (4 at 10 μg/dose and 2 at 20 μg/dose) were administered intramuscularly to healthy adults at 0, 1 and 6 month intervals. All participants (16–50 years) who were negative for any hepatitis B virus serological markers were vaccinated. Anti-HBs levels were assessed 1 month and 1 year after the third vaccination. The anti-HBs seroconversion rate (anti-HBs >10mIU/ml) was 99.4 % (99.9 % for 10 μg dose groups and 97.9 % for 20 μg dose groups) 1 month after the third vaccination, and the anti-HBs seroreversion rate was 77.0 % (75.3 and 82.6 %) 1 year after the third vaccination (n = 1036). One month after completing the vaccinations, the seroconversion rates were not significantly different (100.0, 100.0, 99.6, 100.0 %) for the four 10 μg dose and two 20 μg dose groups (99.1, 96.9 %). One year after the third vaccination, the group II positive rate was significantly higher than the other three 10 μg dose groups, and the group VI positive rate was significantly higher than the other 20 μg dose group. Groups II and VI showed a significantly higher positive rate and anti-HBs geometric mean titer (GMT) than the other groups. The anti-HBs level declined with increasing age, and the seroreversion rate and GMT decreased over time. All six vaccines had high anti-HBs seroconversion rates and good immunization effects. The 10 μg dose vaccine (Dalian High-Tech) and the 20 μg dose vaccine (GlaxoSmithKline) are recommended for adults.

Chronic hepatitis B in Korean Americans: decreased prevalence and poor linkage to care

Background

Chronic hepatitis B virus(HBV) infection is a major cause of liver related morbidity and mortality. HBV infection remains largely underdiagnosed in Asian American population, and it is also poorly linked to clinical care. We, therefore, assessed the HBV prevalence and evaluated linkage to care among Korean Americans in order to develop strategic plans to reduce the impact of HBV in a high risk community.

Methods

Serologic screening and survey were provided to 7157 Korean American adults (age 21–100) in New Jersey between December 2009 and June 2015. All participants were tested for hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (anti-HBs), and hepatitis B core IgG antibody (anti-HBc). Additional survey was conducted on the subjects chronically infected with HBV on their history of infection. Self-administered questionnaires were employed to evaluate demographic and epidemiologic characteristics.

Results

Of those 7157screened, 171 (2.4 %) were HBV infected, 2736(38.2 %) were susceptible to HBV, and 4250(59.4 %) were immune. The prevalence of chronic HBV varied between the age groups: 1.18 % (age21-30); 2.53 % (age 31–40); 2.76 % (age 41–50); 2.90 % (age 51–60); 2.06 % (age 61–70); and 1.37 % (age 71–100). The rate of HBsAg was significantly higher in males (3.04 %) as compared to females (1.93 %). At least 75 % of these HBV infected subjects had been previously diagnosed, but were not engaged in care.

Conclusion

This screening study suggests that the HBV prevalence in Korean Americans is significantly lower than currently understood. On the other hand, many of the individuals chronically infected with HBV cannot access care, suggesting a poor linkage-to-care (LTC). Further, a large percentage of the population is still susceptible to HBV. Study findings will be used to develop strategies to tailor community-based HBV screenings and LTC to the high risk populations.

Hepatitis B surface antibodies in medical students from a public university in Puebla, Mexico

Although preventable with vaccination, Hepatitis B virus (HBV) infection is a major health concern, with ∼400 million people at risk of developing the chronic form of the disease worldwide. The anti-HBV vaccine consists of a recombinant HBV surface antigen (HBsAg), which induces specific anti-HBs antibodies and confers 95% protection for >20 y. The aim of the present study was to analyze the response to HBV vaccination by measuring anti-HBs antibodies in serum samples from medical students of a public university in Puebla, Mexico. HBV infection markers HBsAg and anti-HBs, were also determined. A total of 201 students were included and vaccination coverage was found at 54%. Overall seropositivity for HBsAg, anti-HBc and anti-HBs determined by ELISA was 0.5%, 1.0% and 47%, respectively. Protective levels of anti-HBs >10 mIU/mL were found in 93.2% of subjects vaccinated with 2 or 3 doses and in 40% of those vaccinated with a single dose; while only 4.8% of unvaccinated subjects were anti-HBs positive. The response to the HBV vaccine was different in each participant, despite similar vaccination scheme. A history of blood transfusion/organ transplant or more than 2 sexual partners was significantly associated with anti-HBc positivity, OR = 399 (p = 0.010) and OR = 19.9 (p = 0.044), respectively. HBV immunization coverage was low in our sample compared with reports from countries with similar HBV prevalence, but anti-HBs in vaccinated individuals were in the expected range. It is important to promote HBV vaccination and awareness among medical students, due to their exposure risk.

Age-dependent decrease of anti-HBs titers and effect of booster doses using 2 different vaccines in Palestinian children vaccinated in early childhood

Immunization against hepatitis B virus (HBV) has proven to be highly effective and led to significant reduction of new infections worldwide. However, protective immunity measured by anti-HBs titers may decrease to critical levels in the years after basal immunization, particularly in case of exposure to HBV variants different from the vaccine strain. We tested 400 Palestinian children between one and 19 years of age for their anti-HBs titer, challenged the immune memory of those with low or absent anti-HBs with 2 types of hepatitis B vaccines and determined thereafter the anti-HBs titer. At the age of one, 92.2% of the children presented with protective anti-HBs titers (≥ 10 mIU/ml) with the majority having ≥ 100 mIU/ml. Protective immunity was still high at ages 2 (87.5%) and 4 (95%), declining by age 5 and 6 (from 69.2% to 66.7%) and down to an average of 39.8% between the ages of 7 and 19. 160 children with a nonprotective or low immune response challenged with either the yeast-derived Engerix-B or the mammalian cell-derived preS1-containing Sci-B-Vac vaccine showed an anamnestic immune response. 92.4% and 85.9% of the children challenged with one dose Sci-B-Vac and Engerix-B presented with anti-HBs titers >100 mIU/ml respectively. Our results reveal that vaccine-induced protective anti-HBs titers against HBV decrease rapidly beyond the age of 6 in Palestinian children, but can be strongly enhanced with a single booster vaccine dose, independent of brand and antigen composition. Our data suggest that a booster vaccine dose against HBV during school years may be useful.

Markers of Protection in Children and Adolescents Six to Fourteen Years After Primary Hepatitis B Vaccination in Real Life: A Pilot Study

BACKGROUND

Not many data are available on long-term immunity against hepatitis B (HB) for children vaccinated under real-life conditions.

METHODS

Two hundred and thirty-two children and adolescents vaccinated 6-14 years earlier in pediatric practices were examined for conditions of vaccination and markers of protection as anti-HBs, anamnestic response to a booster dose and cell-mediated immunity.

RESULTS

Fifty-six percent of the participants were vaccinated according to the German vaccination recommendations (group 1). In 44.0% (group 2), these recommendations were not followed. Anti-HBs concentrations of ≥10 IU/L were found in 53.1% of group 1 and 45.1% of group 2 participants. A booster dose resulted in 91 of 99 participants in having an anamnestic response, in 3 (5.9%) of group 1 and 5 (10.4%) of group 2 anti-HBs remained below 10 IU/L. In group 1, postbooster anti-HBs concentration was inversely correlated with time since the last vaccination. Cellular immune responses were seen in only 5% of revaccinated individuals before the booster, increasing to 30% thereafter.

CONCLUSIONS

Under real-life conditions about half of vaccinees have lost protecting antibodies 6-14 years after vaccination in infancy, but in approximately 90% of them, immune memory was demonstrated. However, as memory may wane, revaccination at a time when boostability is still present might be considered.

Hepatitis B Virus Revaccination With Standard Versus Pre-S Vaccine in Previously Immunized Patients With Celiac Disease

OBJECTIVE

Previous studies have suggested that hepatitis B virus (HBV) vaccines may be less immunogenic in individuals with celiac disease (CD). A pre-S vaccine (Sci-B-Vac) has demonstrated superior immunogenicity compared with standard HBV vaccines in several diseases. We compared the short-term immunogenicity of a pre-S vaccine with a HBV vaccine (Engerix B) for repeat vaccination of seronegative, previously immunized patients with CD.

METHODS

Participants were 1 to 18-year-old children with CD who despite standard HBV vaccines in infancy had nonprotective hepatitis B surface antibody (HBs-Ab) concentrations (≤10 mIU/mL). Patients were randomized to receive either Engerix B or pre-S vaccine. HBs-Ab concentrations were measured 1 month after the first dose. For those who had not responded after 1 dose, measurement was repeated after the third dose.

RESULTS

Children (n = 82) were analyzed (42 pre-S vaccine and 40 Engerix B). Baseline characteristics were similar for both groups, including gluten-free diet status. Both arms showed high response rates following the first injection: 41 (98%) versus 35 (87%) for pre-S vaccine and Engerix B recipients, respectively (P = 0.08). All other patients responded when measured after dose 3. HBs-Ab concentrations (mIU/mL) were higher in the pre-S vaccine group (median 925, interquartile range [IQR] 424-1000) than the Engerix B group (median 363, IQR 106-996, P = 0.005). Twenty (48%) of the pre-S vaccine recipients were "high responders" (>1000 mIU/mL) versus 10 (25%) in Engerix B recipients (P = 0.008).

CONCLUSIONS

Both vaccines elicited adequate booster responses in most previously vaccinated patients with CD with nonprotective HBs-Ab concentrations. Pre-S vaccine administration resulted in higher Hbs-Ab concentrations. Our data suggest that a single dose of either vaccine is sufficient to raise titers to protective levels in most patients with CD.

Impact of immunosuppressive therapy on hepatitis B vaccination in inflammatory bowel diseases

BACKGROUND AND AIMS

The vaccination rate against hepatitis B virus (HBV) is low in inflammatory bowel disease (IBD) patients. The Consensus from the European Crohn's and Colitis Organisation on opportunistic infections recommends testing all IBD patients for HBV at diagnosis and vaccinating all HBV-negative patients. We compared the efficacy of HBV vaccine between IBD patients and healthy controls and investigated the impact of immunosuppressive therapy on vaccine response in IBD patients.

MATERIALS AND METHODS

IBD patients and healthy adult workers were vaccinated against HBV following a standard protocol (at 0, 1, and 6 months; Engerix B). The efficacy of vaccination was evaluated at 8 months by a titer of antibodies against hepatitis B surface antigen (anti-HBs).

RESULTS

Among 164 participants (96 with IBD and 68 healthy workers), the level of anti-HBs was greater than 10 IU/l in 80.2 and 94.1% (P=0.0115) of IBD patients and healthy controls, respectively, and anti-HBs levels greater than 100 IU/l were seen in 45.8 versus 77.9% (P<0.0001) of IBD patients and healthy controls, respectively. The median level of anti-HBs was significantly higher in healthy controls (497.0±386.2) than in IBD patients (253.9±34.5) (P<0.0001). None of the baseline characteristics of IBD patients, including immunomodulators and antitumor necrosis factor therapy, influenced the vaccine response. In the multivariate analysis, ileal disease was the only factor associated with a lower response to the vaccine (odds ratio=3.2; 95% confidence interval=1.0-9.7; P=0.049).

CONCLUSION

The response rate to HBV vaccination is significantly lower in IBD patients than in the general population. Immunosuppressive therapy for IBD did not influence the vaccine response.

Immune Abnormalities in Fontan Protein-Losing Enteropathy: A Case-Control Study

OBJECTIVE

To comprehensively characterize the immunologic characteristics of patients with protein-losing enteropathy (PLE) post-Fontan and compare them with patients without PLE post-Fontan.

STUDY DESIGN

Patients with PLE post-Fontan and age-matched controls post-Fontan were prospectively studied with laboratory markers of immune function. Infectious history was obtained by interview and chart review. The groups' demographics, cardiac history, immune characteristics, and infection history were compared using appropriate 2-group statistics.

RESULTS

A total of 16 patients enrolled (8 patients with PLE and 8 controls). All patients with PLE had lymphopenia compared with 25% of controls (P = .01). All patients with PLE had markedly depressed CD4 T cell counts (median 58 cells/μL) compared with controls (median 450 cells/μL, P = .0002); CD4% was also low in the PLE group (12.3%) and normal in control (36.9%, P = .004). Both groups had mildly depressed CD8 T cells and normal to slightly elevated natural killer and B-cell subsets. A majority of patients with PLE (62.5%) had negative titers to measles, mumps, and rubella vaccination, compared with no control Fontan with a negative titer (P = .03). Despite profoundly low CD4 counts, the frequency of infection was not different between groups with no reported opportunistic infections.

CONCLUSIONS

Patients with Fontan-associated PLE have extensive quantitative immune abnormalities, particularly CD4 deficiency. These immune abnormalities are similar to those found in non-Fontan patients with PLE caused by intestinal lymphangiectasia.

Effect of Immunosuppressive Therapies for the Treatment of Inflammatory Bowel Disease on Response to Routine Vaccinations: A Meta-Analysis

BACKGROUND

Several studies have evaluated the effect of immunosuppressive therapy for the treatment of inflammatory bowel disease (IBD) on response to routine vaccinations. The overall effect of specific classes of medications (i.e., immunomodulator vs. biologics) on vaccine response remains undefined. The aim of this study was to determine the effect of each class of immunosuppressive therapy in IBD patients on response to routine vaccinations.

METHODS

A comprehensive search of PubMed/MEDLINE, Scopus, CINAHL, and Cochrane databases was performed (December 2014). All studies on adults comparing vaccine response among IBD patients on immunosuppression with non-immunosuppressed patients were included. Meta-analysis was performed using the Mantel-Haenszel (fixed effects) model with odds ratio (OR) to assess for adequate vaccine response.

RESULTS

In the pooled analysis of nine studies (N = 1474), we found that there was nearly a 60 % lower chance of achieving adequate seroprotection in the group that received immunosuppressive therapy compared to the group that was not on any immunosuppressive therapies (OR 0.41 95 % CI 0.30, 0.55, p < 0.001). Specifically, we also demonstrated that patients on immunomodulator monotherapy had a twofold higher probability of achieving adequate immune response to vaccination, compared to patients on anti-tumor necrosis factor (anti-TNF) monotherapy (OR 1.92 95 % CI 1.30, 2.84).

CONCLUSION

In conclusion, IBD patients on immunosuppressive therapy have a significantly lower response to routine vaccinations. The greatest effect is seen among patients on anti-TNF and combination immunosuppressive therapy. Routine monitoring of vaccine titers post-vaccination is important to ensure that adequate immunologic response has been achieved among IBD patients.

Hepatitis B vaccination is effective by subcutaneous route in children with bleeding disorders: a universal data collection database analysis

Subcutaneous (SQ) vs. intramuscular (IM) vaccination may cause fewer injection site complications in children with bleeding disorders, but little is known about comparative immunogenicity. To compare immunogenicity of hepatitis B virus (HBV) vaccination administered SQ or IM to individuals <2 years old with bleeding disorders, we performed a retrospective analysis of HBV surface antibody titres among patients enrolled in the universal data collection database who had received three doses of HBV vaccine solely by one route (SQ or IM). Data reviewed were from an initial visit before 24 months of age, until time of hepatitis antibody titre testing. The SQ and IM study groups did not differ in demographics, haemophilia type or severity or bleeding history. The mean age at the time of HBV surface antibody (anti-HBs) testing was 56.9 ± 20.3 months. Eighty-five of 92 subjects (92.4%) who received vaccine SQ developed a positive antibody titre (>12 IU/L), compared to 101/114 (88.6%) who received IM (P = 0.30). There was no statistically significant difference in distribution of titre values. The average age of the subjects at time of testing was 53 ± 20 months in the SQ group vs. 60 ± 20 months in the IM group (P = 0.02). The average time between the last dose of vaccine and anti-HBs testing was 47.6 ± 18.5 months among SQ vaccinated subjects vs. 51.6 ± 20.5 months in the IM group (P = 0.2). Immunogenicity to hepatitis B vaccination by the SQ and IM routes is similar.

Vaccinating the inflammatory bowel disease patient

Current therapeutic options for patients with inflammatory bowel disease (IBD) include several agents that can alter their immune response to infections. Effective vaccines exist and offer protection against a number of infectious diseases. However, recent data has shown that IBD patients are inadequately vaccinated and, as a result, at risk to develop certain preventable infections. Furthermore, gastroenterologists' knowledge regarding the appropriate immunizations to administer to their IBD patients is suboptimal. This review article focuses on the current immunization schedule for the IBD patient and stresses the important role of the gastroenterologist as an active participant in the management of vaccination in their IBD patients.

Old and new adjuvants for hepatitis B vaccines

The safety and immunogenicity profiles of currently available recombinant hepatitis B vaccines are excellent. However, it remains a real challenge to induce protective immunity in the target groups that respond poorly or not at all to conventional vaccines. Ideally, a hepatitis B vaccine can be developed that conveys lifelong protection against infection rapidly after the injection of a single dose. Although this goal is far from being reached, important improvements have been made. Novel vaccine adjuvants have been developed that enhance the immunogenicity of recombinant hepatitis B vaccines while maintaining a good safety profile. The different adjuvants and adjuvant systems that are discussed herein have all been thoroughly evaluated in clinical trials and some have reached or are close to reach the market.

Prophylactic vaccination against hepatitis B: achievements, challenges and perspectives

Large-scale vaccination against hepatitis B virus (HBV) infection started in 1984 with first-generation vaccines made from plasma of chronic carriers containing HBV surface antigen (HBsAg). Thereafter, it was replaced in most countries by second-generation vaccines manufactured in yeast cells transformed with gene S encoding HBsAg. Both generations of vaccines have been applied for universal neonate and early childhood vaccination worldwide and have led to a 70-90 % decrease in chronic HBV carrier rates. However, 10-30% of newborns from HBsAg/HBeAg-positive mothers cannot be protected by passive/active vaccination alone and become chronic HBV carriers themselves. Asymptomatic occult HBV infections are frequent even in those who have protective levels of anti-HBs. Suboptimal protection may be due to heterologous HBsAg subtypes that are present in 99% of HBV carriers worldwide. Second-generation vaccines contain partially misfolded HBsAg and lack preS1 antigen that carries the major HBV attachment site and neutralizing epitopes. Third-generation vaccines produced in mammalian cells contain correctly folded HBsAg and neutralizing epitopes of the preS antigens, induce more rapid protection, overcome nonresponse to second-generation vaccines and, most importantly, may provide better protection for newborns of HBV-positive mothers. PreS/S vaccines expressed in mammalian cells are more expensive to manufacture, but introduction of more potent HBV vaccines should be considered in regions with a high rate of vertical transmission pending assessment of health economics and healthcare priorities. With optimal vaccines and vaccination coverage, eradication of HBV would be possible.

Normal or defective immune response to Hepatitis B vaccine in patients with diabetes and celiac disease

A defective production of protective levels of antibodies to Hepatitis B (HB) vaccine is reported to occur in 4-10% of healthy subjects and a correlation with the presence of specific human leukocyte antigen (HLA) molecules, including DQ2, which also confers genetic predisposition to celiac disease (CD) and type I diabetes mellitus (T1DM), has been suggested.   The aim of this study was to analyze the serological response to HB vaccine and measles-containing vaccines in 69 diabetic patients (T1DM), 42 patients with celiac disease (CD) and 79 healthy control subjects (CT). The median interval between the third dose of HB vaccine and serum collection was 6.8, 3.5, and 4.7 years for T1DM, CD and CT groups, respectively. 50/69 (72%) T1DM patients, 32/42 (76%) CD patients and 61/79 (77%) CT subjects showed protective anti-HBs antibodies after vaccination, with no statistically significant difference. On the contrary, a lower statistically significant difference was found in the mean HBsAb level of T1DM subjects when compared with the other two groups. No correlation between HLA DQ2 expression in T1DM and vaccine response was detected. The comparison of serological response to measles after vaccination also showed no statistically significant differences in the three groups. Contrasting results between these data and those reported in the literature might be due to differences in the time intervals between vaccination and testing. Prospective studies in pathological and healthy groups with the same age at HBV vaccination and with the same time interval for blood sample collection to determine antibody titers are necessary in order to provide more conclusive data.

Preventing infective complications in inflammatory bowel disease

Over the past decade there has been a dramatic change in the treatment of patients with Crohn’s disease and ulcerative colitis, which comprise the inflammatory bowel diseases (IBD). This is due to the increasing use of immunosuppressives and in particular the biological agents, which are being used earlier in the course of disease, and for longer durations, as these therapies result in better clinical outcomes for patients. This, however, has the potential to increase the risk of opportunistic and serious infections in these patients, most of which are preventable. Much like the risk for potential malignancy resulting from the use of these therapies long-term, a balance needs to be struck between medication use to control the disease with minimization of the risk of an opportunistic infection. This outcome is achieved by the physician’s tailored use of justified therapies, and the patients’ education and actions to minimize infection risk. The purpose of this review is to explore the evidence and guidelines available to all physicians managing patients with IBD using immunomodulating agents and to aid in the prevention of opportunistic infections.