DTaP-IPV/Hib Vaccine Primary & Booster Vaccinations Versus Co-administration of DTaP-IPV and Hib Vaccine in Japanese Infants

Primary objective: * To demonstrate the non-inferiority in terms of seroprotection rates (Hib antigen (PRP), Diphtheria, Tetanus, and Pertussis antigens (PT and FHA), and polio types 1, 2 and 3 antigens) of investigational arm (Group A: DTaP-IPV/Hib) versus control arm (Group B: DTaP-IPV and Hib vaccines administered at separate sites), one month after the primary vaccination (all antigens). Secondary objectives: * To describe immune responses against all vaccine antigens with no pre-specified hypothesis, and at all time points (pre-dose 1, post-dose 3, pre-dose 4 and post-dose 4) in the two study groups (Group A and Group B). * To describe the safety after each dose of each vaccine in the two study groups (Group A and Group B). * To describe immune responses against all vaccine antigens with no pre-specified hypothesis, and at all time points (pre-dose 1, post-dose 3, pre-dose 4 and post-dose 4 (Group C)