title: Rapid seroprotection against hepatitis B following the first dose of a Pre-S1/Pre-S2/S vaccine.
abstract: OBJECTIVE
  Will immunization with an experimental Pre-S1/Pre-S2/S hepatitis B vaccine (Bio-Hep-B) induce faster seroprotection using fewer doses as compared with a yeast derived S vaccine (Engerix B).
  
  
  METHODS
  Healthy volunteers, n = 36, mean age 23 y, randomized to receive 2 or 3 doses of both vaccines given months 0 and 6, or 0, 1 and 6.
  
  
  RESULTS
  Following primary immunization, seroprotection occurred in 6, 39, 53 and 60% in the Bio-Hep-B group at weeks 1, 2, 3 and 4, compared with 0, 12, 18 and 12.5% in the Engerix-B vaccinees, respectively. Six months following injection of the first dose, seroprotection was 70 and 25% in Pre-S/S and S vaccinees respectively. Area under the curve in vaccinees of Bio-Hep-B; versus Engerix-B showed mean anti-HBs level of 365 +/- 166 and 85 +/- 48 mIU/ml x day respectively (P = 0.012). At month 7, 100% seroprotection was achieved in both groups while anti-HBs rose from 81 to 28,800 mIU/ml and from 12 to 923 mIU/ml in recipients of Bio-Hep-B and Engerix-B respectively (P < 0.025).
  
  
  CONCLUSIONS
  Bio-Hep-B induces rapid seroprotection against hepatitis B in 60-70% of vaccinees, within 4-24 weeks after the first dose. Two instead of the conventional three doses of the Pre-S/S vaccine may be sufficient to induce adequate seroprotection.
authors.affiliation: Division of Medicine, Hadassah University Hospital, Hebrew University-Hadassah Medical School, Jerusalem, Israel.
authors.forename: M Y
authors.initials: MY
authors.lastname: Shapira
authors.forename: E
authors.initials: E
authors.lastname: Zeira
authors.forename: R
authors.initials: R
authors.lastname: Adler
authors.forename: D
authors.initials: D
authors.lastname: Shouval
mesh_terms: D000328:Adult; D005260:Female; D006509:Hepatitis B / Q000517:prevention & control*; D006510:Hepatitis B Antibodies / Q000097:blood*; D006514:Hepatitis B Surface Antigens / Q000276:immunology*; D017325:Hepatitis B Vaccines / Q000276:immunology*; D006801:Humans; D007114:Immunization; D008297:Male; D011498:Protein Precursors / Q000276:immunology*; D013997:Time Factors; D014614:Vaccines, Synthetic / Q000276:immunology*
chemical_list: D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines; D011498:Protein Precursors; D014614:Vaccines, Synthetic; C050806:presurface protein 1, hepatitis B surface antigen; C050807:presurface protein 2, hepatitis B surface antigen