title: Randomized, comparative trial of 20 micrograms vs 40 micrograms Engerix B vaccine in hepatitis B vaccine non-responders.
abstract: Fifty-two adults who had previously received 4 x 20 micrograms doses of hepatitis B [Engerix-B] vaccine (appropriately administered into the deltoid muscle) and who had failed to develop detectable anti-HBs were randomized to receive a fifth dose of Engerix-B (either 20 micrograms or 40 micrograms) intramuscularly (deltoid). The participants were blinded as to the contents of the syringe. Anti-HBs was tested (by EIA) 3 months after the injection. Anti-HBs results from 45 non-responders were evaluable. Seven vaccinees were excluded; four of these on the basis of failure to have follow-up blood collected and three who were found to be anti-HBc positive (one HBsAg positive). Twelve of 22 (54.5%) of those receiving 20 micrograms of HB vaccine developed anti-HBs, whereas 10 of 23 (43.5%) who received 40 micrograms developed anti-HBs, showing no significant difference between the regimens. The mean geometric titres were 93 +/- 50 and 86 +/- 51 IU l-1, respectively. Vaccinee groups were well matched for age, sex and body mass index and the interval between injection and bleeding. Side-effects in those receiving the double (40 micrograms) dose were no different from those receiving the normal (20 micrograms) adult dose. On the basis of this study, a fifth dose of vaccine in non-responsive vaccinees is recommended. No significant advantage of 40 micrograms over 20 micrograms of vaccine was observed. Whilst smoking and obesity were common in this cohort of non-responders and probably contributed to the individuals primary non-responsive state, these factors had no unfavourable effect on response to a fifth dose of vaccine.
authors.affiliation: Microbiology and Infectious Diseases Department, Women's and Children's Hospital, North Adelaide, Australia.
authors.forename: P N
authors.initials: PN
authors.lastname: Goldwater
mesh_terms: D000293:Adolescent; D000328:Adult; D015992:Body Mass Index; D016022:Case-Control Studies; D004334:Drug Administration Schedule; D005260:Female; D005500:Follow-Up Studies; D006509:Hepatitis B / Q000517:prevention & control*; D006510:Hepatitis B Antibodies / Q000096:biosynthesis; D017325:Hepatitis B Vaccines / Q000008:administration & dosage* / Q000276:immunology*; D006801:Humans; D007117:Immunization, Secondary; D007273:Injections, Intramuscular; D008297:Male; D008875:Middle Aged; D017211:Treatment Failure; D014614:Vaccines, Synthetic / Q000008:administration & dosage* / Q000276:immunology*
chemical_list: C075654:Engerix-B; D006510:Hepatitis B Antibodies; D017325:Hepatitis B Vaccines; D014614:Vaccines, Synthetic