Safety and Dose Ranging Study of Acellular Pertussis and Acellular Pertussis -Tetanus-Diphtheria Booster Vaccines in Healthy Adults Ages 18 to 40 Years

Acellular pertussis (aP) vaccine was administered with different antigen doses intramuscularly in the upper deltoid region of the subject's non-dominant arm.

Tetanus, reduced diphtheria, and acellular pertussis (TdaP) vaccine was administered with different antigen doses intramuscularly in the upper deltoid region of the subject's non-dominant arm.

Licenced TdaP booster vaccine was administered intramuscularly in the upper deltoid region of the subject's non-dominant arm.

To ensure all subjects receive a tetanus and diphtheria booster vaccination, an injection was administered on Study Day 30, one month after the administration of the investigational vaccine.

Subjects received one injection of saline solution at one month after vaccination.