The purpose of the study is to evaluate immunogenicity and safety of three different doses of candidate hexvalent vaccine in comparison to co-administration of EupentaTM Inj. and Imovax® Polio in separate injections at four weeks after completion of three-dose primary series at 6-10-14 weeks of age when administered to healthy infants and thereby to select the optimal dose of candidate vaccine

Inclusion Criteria:

1. A male or female healthy (i.e. free of obvious health problems) infant who have reached at least 42 days (6 weeks) of age and not more than 56 days (8 weeks) of age at the time of first vaccination
2. Born at full term pregnancy (Gestational age ≥ 37 weeks)
3. Body weight ≥ 3.2 kg at the time of screening
4. Received one dose of hepatitis B mono-vaccine within seven days of birth
5. Born to both hepatitis B virus surface antigen (HBsAg) and human immunodeficiency virus (HIV) negative mother
6. Subject's parent(s) or Legally Acceptable Representative (LAR) able to understand and comply with planned study procedures
7. Written informed consent by subject's parent(s) or LAR

Exclusion Criteria:

1. Previously received any dose of diphtheria, tetanus, pertussis, polio and/or Hib containing vaccines
2. History of previous or concurrent vaccinations other than hepatitis B, Bacillus Calmette-Guerin (BCG), rotavirus and pneumococcal vaccine
3. Known or suspected history of diphtheria, tetanus, pertussis, hepatitis B, poliomyelitis, or Hib diseases
4. Household contact and/or intimate exposure in the previous 30 days to an individual with ascertained diphtheria, pertussis, hepatitis B, polio or Hib diseases
5. Experienced fever ≥ 38°C (100.4°F) within the past three days prior to screening
6. Experienced significant acute or chronic infections requiring systemic antibiotic treatment or antiviral therapy within the past seven days prior to screening
7. Known or suspected immune disorder or immunodeficient condition
8. Receipt of immunoglobulin or blood-derived product since birth
9. Chronic administration (defined as more than 14 days) of immunosuppressant or other immune-modifying drugs since birth. For corticosteroids, this will mean prednisone, or equivalent, ≥0.5mg/kg/day. Inhaled and topical steroids are allowed.
10. History of bleeding disorder contraindicating intramuscular injection
11. Major congenital defects or serious chronic illness
12. History of any neurological disorders or seizures
13. History of allergic reactions to any vaccine components including excipients and preservatives (neomycin, streptomycin, polymyxin B, yeast or etc.)
14. History of allergic reactions to latex
15. Participation in another interventional trial or received any investigational product within 30 days before to the enrollment
16. Plan to leave the area of the study site before the end of the study period
17. Infants who are considered unsuitable for the clinical study by the investigator