As per request by the Heath Authorities, the present clinical study will assess the immunogenicity and safety of sanofi pasteur's DTacP-IPV// PRP~T combined vaccine (PENTAXIM™) as a three-dose primary vaccination at 2, 3, and 4 months of age or 3, 4 and 5 months of age followed by a booster dose at 18-20 months of age as compared to commercially available DTacP, Hib conjugate (Act-HIB™) and IPV (IMOVAX Polio™) monovalent vaccines in order to meet the requirements for registration of the product in People's Republic of China.

Inclusion Criteria :

• Aged 2 months (60 to 74 days) inclusive on the day of inclusion
• Born at full term pregnancy (³36 weeks) 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
• Any vaccination performed or planned in the 4 weeks preceding the first trial visit (except BCG and Hepatitis B, which can not be given within 8 days before the first study visit)
• Vaccination planned in the 4 weeks following any trial vaccination (except BCG and Hepatitis B, which can not be given within 8 days before or after the study vaccine(s) administration)
• History of diphtheria, tetanus, pertussis, poliomyelitis, Haemophilus influenzae type b infection (confirmed either clinically, serologically or microbiologically)
• Clinical or serological evidence of systemic illness including Hepatitis B, Hepatitis C and/or 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 seizures
• Febrile illness (axillary temperature ≥ 37.1°C) or acute illness on the day of inclusion