Humoral immunity 10 years after booster immunization with an adolescent and adult formulation combined tetanus, diphtheria, and 5-component acellular pertussis vaccine in the USA

The original phase III clinical trial, as well as the 1-, 3-, and 5-year serology follow-up studies were conducted prior to mandatory registration. The 10-year serology follow-up data collection was performed as part of a repeat Tdap administration clinical trial that was registered under clinicaltrials.gov number NCT01439165.