Immune response of HLA DQ2 positive subjects, vaccinated with HBsAg/AS04, a hepatitis B vaccine with a novel adjuvant
Faculty of Medicine and Health Sciences
Vaccine / International Society for Vaccines. - Amsterdam
, p. 2597-2602
University of Antwerp
About 510% of the general adult population respond inadequately to hepatitis B vaccination. The histocompatibility leucocyte antigen (HLA) DQ2, DR3 and DR7 phenotypes have been linked with non-responsiveness to hepatitis B vaccination. A first part of our study determined the prevalence of the HLA DQ2 allele in a healthy population, aged 1550 years. We found 35% of our study population (n=1008) positive for the HLA DQ2 allele. Positive subjects for HLA DQ2 were subsequently invited to participate in a trial and were to be given either the HBsAg/AS04 hepatitis B vaccine or a licensed hepatitis B vaccine (Engerix-B).1 Both contained 20 μg of recombinant HBsAg. The HBsAg/AS04 vaccine was administered on a 0 and 6 months schedule whilst the comparator vaccine was given according to the standard 0, 1 and 6 months schedule. The experimental vaccine was formulated on a novel adjuvant containing 3′ deacylated monophosphoryl lipid A (3D-MPL) and alum. A total of 230 subjects were enrolled into the vaccination study. At month 7, 99% of the subjects had a protective titre (≥10 mIU/ml) with a geometric mean titre (GMT) of 6613 mIU/ml in the group receiving HBsAg/AS04 versus 97% seroprotected with a GMT of 2315 mIU/ml in the other group. Both vaccines, with their respective schedule, give very high seroprotection rates (>96%). Our data suggest that HLA DQ2 positivity is not a good marker for non- or poor-responsiveness. The HBsAg/AS04 vaccine was more reactogenic mainly because of an increased local reactogenicity. Both vaccines, especially HBsAg/AS04, are highly immunogenic and well tolerated by the study subjects.