Study to Evaluate the Immunogenicity and Safety of LBVD(Hexavalent Vaccine), Given to Healthy Infants at Primary Series

The purpose of this study is to evaluate immunogenicity and safety of different doses of candidate hexavalent vaccine in comparison to co-administration of Pentavalent vaccine and Poliomyelitis Vaccine (Inactivated) 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(Stage 1) and to demonstrate lot-to-lot consistency of three lots of LBVD (Stage 2)

Stage 1 (Dose-level Finding;Phase 2) 1\. To compare the immunogenicity and safety of three LBVD vaccine candidates, varying at different dose levels, to the Control vaccines at 4 weeks after a three-dose primary series of vaccination and thereby, select an optimal vaccine dose level for Stage 2 Stage 2 (Evaluation of Safety, Immunogenicity, and Lot-to-lot Consistency;Phase 3) 1. To demonstrate the non-inferiority and lot-to-lot consistency in the immunogenicity of three separate lots of LBVD to the Control vaccines at 4 weeks after a three-dose primary series of vaccination given at 6-, 10- and 14-week of age 2. To demonstrate the safety and immunogenicity of LBVD at 4 weeks after a three-dose primary series of vaccination given at 6-, 10- and 14-week of age