title: Immunogenicity of HBV vaccine during stated shelf-life.
abstract: Thiomersal has been used as preservative in multi-dose vials of hepatitis B vaccine (Engerix-B). Due to safety concerns, thiomersal was replaced with 2-phenoxyethanol (2PE) as preservative in multi-dose vials. The potency of 2PE preserved hepatitis B vaccine multiple use vials was measured over the shelf-life in terms of immunogenicity, reactogenicity and safety. This single-blind, randomized study was conducted with the assistance of employees of GlaxoSmithKline Biologicals, makers of the Engerix-B vaccine. Four hundred twenty subjects aged > or =18 years were randomized to receive three doses (0, 1, 6 months) of 2PE preserved hepatitis B vaccine kept on the shelf <12 months (2PE New group), 2PE preserved hepatitis B vaccine kept on the shelf >18 months (2PE Old group), or thiomersal preserved hepatitis B vaccine [HBV(Thio) group]. Anti-HBs was measured by GlaxoSmithKline Biologicals post-vaccination; the reactogenicity and safety of the vaccines were assessed. Protective anti-HBs levels (> or =10 mIU/ml) were measured one month after dose 3. The results showed protective levels in 86.8% (2PE New), 89% (2PE Old) and 95.3% [HBV(Thio)]. There was no difference detected between the 2PE New and 2PE Old groups in terms of anti-HBs seroprotection rates and geometric mean concentrations one month after dose 3. However, both 2PE groups had significantly lower seroprotection rates than the HBV(Thio) group and the number of non-responders was higher in the 2PE groups than in the Thio group. A antibody response rates over time were similar between the 2PE New and Old groups. The reactogenicity profiles were acceptable and the ranges were similar for each group. The shelf-life of the vaccines had no impact on immunogenicity or reactogenicity and 2PE preserved hepatitis B vaccine can be considered stable over time.
authors.affiliation: Department of Microbiology, College of Public Health, University of the Philippines, Ermita, Manila, Philippines. ninagloriani@yahoo.com
authors.forename: Nina G
authors.initials: NG
authors.lastname: Gloriani
authors.forename: Karthik
authors.initials: K
authors.lastname: Srinivasa
authors.forename: Hans L
authors.initials: HL
authors.lastname: Bock
authors.forename: Bernard
authors.initials: B
authors.lastname: Hoet
mesh_terms: D000328:Adult; D004334:Drug Administration Schedule; D004356:Drug Storage / Q000379:methods / Q000592:standards; D005026:Ethylene Glycols / Q000009:adverse effects*; D005260:Female; D006510:Hepatitis B Antibodies / Q000378:metabolism*; D006514:Hepatitis B Surface Antigens / Q000276:immunology*; D017325:Hepatitis B Vaccines / Q000008:administration & dosage / Q000276:immunology*; D006801:Humans; D008297:Male; D011310:Preservatives, Pharmaceutical / Q000009:adverse effects*; D013849:Thimerosal / Q000009:adverse effects; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000276:immunology; D055815:Young Adult
chemical_list: C075654:Engerix-B; D005026:Ethylene Glycols; D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines; D011310:Preservatives, Pharmaceutical; D014614:Vaccines, Synthetic; D013849:Thimerosal; C005398:phenoxyethanol