This study is designed to assess the immunogenicity and safety of PENTAXIM™ combined vaccine versus TETRAXIM™ vaccine to support registration of PENTAXIM™ in South Korea.

Primary Objective:

To demonstrate the non-inferiority in terms of seroprotection rates (Diphtheria, Tetanus, Polio types 1, 2 and 3, Polyribosyl Ribitol Phosphate [PRP]) and vaccine response rates to acellular Pertussis antigens of sanofi pasteur's PENTAXIM™ vaccine versus sanofi pasteur's TETRAXIM™ and Act (Haemophilus influenzae type b) HIB™ vaccines, one month after the three-dose primary vaccination.

All participants will receive three primary doses of their assigned study the vaccine, on Days 0, 60, and 120. They will be assessed for immunogenicity on Day 0 before vaccination and Day 150 post-vaccination. Safety will be assessed for all participants throughout the study, up to Day 157.

Inclusion Criteria:

• Aged 2 months (56 to 70 days) inclusive on the day of inclusion
• Born at full term of pregnancy (≥ 37 weeks) and with a birth weight ≥ 2.5 kg
• Informed consent form signed by the parent(s) or other legal representative
• Able to attend all scheduled visits and to comply with all trial procedures

Exclusion Criteria:

• Participation in another clinical trial in the 4 weeks preceding the trial inclusion
• Planned participation in another clinical trial during the present trial period
• Congenital or acquired immunodeficiency, immunosuppressive therapy such as long term systemic corticosteroids therapy
• Systemic hypersensitivity to any of the vaccine components or history of a life threatening reaction to the trial vaccine or a vaccine containing the same substances
• Chronic illness at a stage that could interfere with trial conduct or completion
• Blood or blood derived products received in the past or current or planned administration during the trial (including immunoglobulins).
• Any vaccination in the 3 weeks preceding the first trial vaccination.
• History of diphtheria, tetanus, pertussis, poliomyelitis, Haemophilus influenzae type b infection (confirmed either clinically, serologically or microbiologically).
• Clinical or known serological evidence of systemic illness including Hepatitis B, Hepatitis C and/or Human Immunodeficiency Virus (HIV) infection
• Previous vaccination against the diphtheria, tetanus, pertussis, poliomyelitis diseases or Haemophilus influenzae type b infection with the trial vaccine or another vaccine.
• Thrombocytopenia or a bleeding disorder contraindicating intramuscular vaccination
• History of/current major neurological diseases or seizures.
• Febrile illness (axillary temperature ≥ 38ºC) or acute illness on the day of inclusion.
• Known family history of congenital or genetic immuno-deficiency.