Healthy infants were randomized ( 5:1 ) and primed at 2 , 4 and 6 months of age with HibMenCY-TT and diphtheria-tetanus-acellular pertussis-hepatitis B-inactivated poliovirus ( DTaP-HBV-IPV ) vaccine ; or Hib-TT and DTaP-HBV-IPV ( control ) .