The immunogenicity of GSK’s recombinant hepatitis B vaccine in children: a systematic review of 30 years of experience

<p><b>Introduction</b>: The World Health Organization recommends hepatitis B virus (HBV) vaccines to be included in national immunization schedules everywhere, and has adopted the strategic goal of halting viral hepatitis as a major public health threat by 2030, under which vaccination plays a major role. <i>Engerix</i>™ B (<i>GSK HepB</i>, GSK, Belgium) was the first recombinant HBV vaccine to be licensed, and marked its 30th anniversary in 2016.</p> <p><b>Areas covered</b>: We conducted a systematic review of the literature summarizing 30 years of immunogenicity and safety data for <i>GSK HepB</i> in children and adolescents.</p> <p><b>Expert commentary</b>: Primary 3-dose vaccination of healthy infants and children, including infants born to HBsAg-positive mothers, using the standard 0, 1, 6 month schedule was associated with seroprotection rates ≥96.0%. In high-risk infants, vaccine efficacy at year 5 was 96.0% after 3-dose priming in infancy and immunoglobulin at birth. Lower seroprotection rates were observed in children with severe underlying disease including human immunodeficiency virus infection and cancer. <i>GSK HepB</i> had a clinically acceptable safety profile in all of the populations studied. HBV vaccines have demonstrated long-term impacts on rates of fulminant hepatitis, chronic liver disease and hepatocellular carcinoma. <i>GSK HepB</i> will continue to contribute to global HBV control for the foreseeable future.</p

The immunogenicity and safety of GSK’s recombinant hepatitis B vaccine in adults: a systematic review of 30 years of experience

<p><b>Introduction</b>: <i>Engerix</i> B (<i>GSK HepB</i>, GSK, Belgium) was the first recombinant hepatitis B virus vaccine to be licensed, and marked its 30^th anniversary in 2016. Vaccination of adult populations against HBV is usually implemented on a risk-based approach with varying degrees of success. Confirmation of ongoing vaccine effectiveness requires monitoring the performance of HBV immunization as reported in individual studies, using systematic methods.</p> <p><b>Areas covered</b>: We conducted a systematic review of the literature to summarize 30 years of immunogenicity and safety data for <i>GSK HepB</i> in adult populations.</p> <p><b>Expert commentary</b>: Primary 3-dose vaccination of healthy individuals is generally associated with seroprotection rates of 90% or more, although seroprotection decreases with older age. Accelerated 0, 1, 2-month or 0, 7 and 21-day schedules require the recommended booster dose to achieve similar rates of seroprotection. Lower rates of seroprotection were also observed in adults with underlying chronic disease and with a weakened immune system. <i>GSK HepB</i> had a clinically acceptable safety profile in all of the populations studied, including individuals with underlying co-morbidities and immunosuppression. <i>GSK HepB</i> will continue to contribute to global HBV control for the foreseeable future. Further investigation is needed into how to optimize seroprotection in less immune-competent groups.</p

Systematic literature review comparing rapid 3-dose administration of the GSK tick-borne encephalitis vaccine with other primary immunization schedules

<p><b>Introduction</b>: Tick-borne encephalitis (TBE), which is endemic across large regions of Europe and Asia, is most effectively prevented through vaccination. Three-dose primary TBE vaccination schedules are either rapid (0,7,21-days) or conventional (0,28–84-days, 9–12-months). The second dose can also be administered at 14 days for faster priming and sero-protection).</p> <p><b>Areas covered</b>: We used a three-step selection process to identify 21 publications comparing the immunogenicity and/or safety of different schedules.</p> <p><b>Expert commentary</b>: Priming with two or three TBE vaccine doses was highly immunogenic. After conventional priming (0–28 days), 95% adults and ≥95% children had neutralization test (NT) titers ≥10 at 14 days post-dose-2 compared with 92% adults and 99% children at 21 days post-dose-3 (rapid schedule). Most subjects retained NT titers ≥10 at day 300. A single booster dose induced a strong immune response in all subjects irrespective of primary vaccination schedule or elapsed time since priming. GMT peaked at 42 days post-dose-1 (i.e., 21 days post-dose 3 [rapid-schedule], or 14–28 days post-dose-2 [conventional-schedule]), and declined thereafter. Adverse events were generally rare and declined with increasing doses. In the absence of data to recommend one particular schedule, the regimen choice will remain at the physician’s discretion, based on patient constraints and availability.</p

Post-exposure prophylaxis (PEP) for rabies with purified chick embryo cell vaccine: a systematic literature review and meta-analysis

<p><b>Introduction</b>: Fifteen million people each year receive post-exposure prophylaxis (PEP) to prevent rabies, yet the disease remains neglected and highly under-reported.</p> <p><b>Areas covered</b>: In this systematic literature review, we assessed the immunogenicity, efficacy, and safety of a purified chick embryo cell-culture rabies vaccine (PCECV) for PEP against rabies by intramuscular (IM) or intradermal (ID) administration. We performed meta-analyses to compare immunogenicity according to the route of vaccine administration, study population, and PEP regimen, such as number of doses, and concomitant rabies immunoglobulin.</p> <p><b>Expert commentary</b>: There were 54 estimates of immune responses to vaccination, which showed that in the overall population, after starting PEP with PCECV by the IM or ID route (≥2.5 IU per dose), almost all individuals had rabies virus neutralizing antibody (RVNA) titers above the World Health Organization (WHO) recommended serological threshold for an adequate immune response to vaccination (RVNA ≥0.5 IU/ml by day 14). In the overall population, PCECV had an acceptable safety profile. However, given that there are 59,000 human rabies deaths reported annually, the challenge is to improve access to PCECV for PEP against human rabies.</p