Infants (N=459) were randomly assigned to receive either Infanrix™ hexa or Hexavac™ vaccines at 2, 4 and 6 months of age as a primary vaccination schedule. The immunogenicity of the hepatitis B component was statistically significantly higher for Infanrix™ hexa compared to Hexavac™ in terms of both seroprotection (98.6% versus 94.7%, p=0.0302) and GMCs (905.6 versus 226.4, p<0.0001). Significantly (p≤0.0001) higher antibody levels against diphtheria and the 3 polio components were also induced by Infanrix™ hexa. The responses to tetanus, Hib and pertussis components were similar. The incidences of clinically relevant solicited symptoms, unsolicited symptoms or serious adverse events were low in both groups.