Pertussis is increasingly being recognized as an important cause of
cough illness in adolescents and adults. To evaluate the safety and immunogenicity of an adult formulation of a five-component (
pertussis toxoid, filamentous
hemagglutinin,
pertactin, fimbriae 2 and 3) acellular
pertussis vaccine combined with
diphtheria and
tetanus toxoids, we randomly allocated 749 healthy adolescents and adults from 12-54 years of age recruited from five Canadian communities to receive either
tetanus-
diphtheria vaccine (Td), acellular
pertussis vaccine (aP) or combined
diphtheria-tetanus-acellular pertussis vaccine (TdaP). Subjects and personnel were unaware of the
vaccine allocation. Antibody levels were measured before and one month postimmunization; adverse events were collected at 24 and 72 h and 8 to 10 days. Adverse events were reported in similar frequency amongst the three
vaccine groups. Moderate
pain at the injection site was reported less frequently in the aP group than the TdaP group (10.7% compared to 19.4%; relative risk 0.6, 95% confidence interval 0.3-0.9).
Chills were reported less frequently after Td (5.3%) than after TdaP (12.5%; relative risk 0.4, 95% confidence interval 0.2-0.9). There were no statistically significant differences between recipients of Td and TdaP in
tetanus and
diphtheria antitoxin levels achieved. Antibody response against Bordetella pertussis
antigens was vigorous in all groups although recipients of aP alone had higher levels of antibody levels against
pertussis toxoid, fimbriae, and
agglutinins and lower antibody levels against
pertactin than did TdaP recipients. We conclude that this adult formulation 5-component acellular
pertussis vaccine is safe and immunogenic in adolescents and adults and is a candidate
vaccine for adolescent and adult immunization programs.