Figure 2: Tdap immunogenicity endpoints at one month post-Tdap-vaccination. (A) Geometric mean concentrations of anti-diphtheria and anti-tetanus antibodies at baseline and one month post-vaccination, by group. (B) The percentage of subjects with seroresponse to the pertussis antigens, pertussis toxin (PT), filamentous hemagglutinin (FHA), and pertactin (PRN), by group.