title: Evaluation of a new hepatitis B triple-antigen vaccine in inadequate responders to current vaccines.
abstract: In this double-blind, randomized, controlled study, healthcare professionals with a history of inadequate response to currently available single-antigen hepatitis B vaccines confirmed by measuring hepatitis B surface antibody titer before entry to the study were revaccinated with a 20-microg dose either of a novel triple-antigen (S, pre-S1, and pre-S2) recombinant vaccine or of a present single-antigen (S only) vaccine. Hepatitis B surface antibody titers were measured 8 weeks' post revaccination. A total of 925 individuals were randomized and vaccinated, of whom 915 (98.9%) completed the study and were included in the efficacy analysis. A single dose of the new triple-antigen hepatitis B vaccine (Hepacare) produced a successful response in over three quarters of these subjects who had not mounted an adequate response to current vaccines. The antibody response was statistically significantly superior (P =.002) to that after a single dose of current vaccines. An evaluation of the overall response showed that only the triple-antigen vaccine was able to raise the average antibody response (geometric mean titer [GMT]) to over 100 IU/L. The superior effect of the new vaccine was most pronounced in subjects who were previously complete nonresponders to currently available hepatitis B vaccines. Both vaccines were well tolerated and had similar safety profiles. This study demonstrated that in healthcare workers who had responded inadequately to at least a full course of immunization (median, 5 doses), a single 20-microg dose of a new triple-antigen vaccine induced protective antibody level in more vaccinees (P =.002) and increased the average antibody titer (GMT) in those protected successfully to a greater degree (P <.001) than a further attempt with a current vaccine (Engerix-B).
authors.affiliation: The Royal Free and University College Medical School, London, UK. J.Zuckerman@rfc.ucl.ac.ul
authors.forename: J N
authors.initials: JN
authors.lastname: Zuckerman
authors.forename: A J
authors.initials: AJ
authors.lastname: Zuckerman
authors.forename: I
authors.initials: I
authors.lastname: Symington
authors.forename: W
authors.initials: W
authors.lastname: Du
authors.forename: A
authors.initials: A
authors.lastname: Williams
authors.forename: B
authors.initials: B
authors.lastname: Dickson
authors.forename: M D
authors.initials: MD
authors.lastname: Young
mesh_terms: D000328:Adult; D000368:Aged; D004311:Double-Blind Method; D005260:Female; D006510:Hepatitis B Antibodies / Q000097:blood; D006514:Hepatitis B Surface Antigens / Q000276:immunology*; D017325:Hepatitis B Vaccines / Q000009:adverse effects / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011498:Protein Precursors / Q000276:immunology*
chemical_list: D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines; D011498:Protein Precursors; C050806:presurface protein 1, hepatitis B surface antigen; C050807:presurface protein 2, hepatitis B surface antigen