Haemophilus Influenzae Type B Infection

This clinical trial is conducted in two parts. Part One employs a randomized, partially blinded, dose-escalation, partially active-controlled design. Part Two utilizes a randomized, blinded, placebo-controlled design. Part One is divided into four stages based on age and vaccine dose levels. Part Two consists of the 2-month-old vaccine/placebo groups.

This is a phase II, randomized, double-blind, active-controlled, parallel-group, multicenter study to evaluate the immunogenicity and safety of DTaP-HepB-IPV-Hib hexavalent vaccine LR20062 in healthy infants as primary series at 2, 4, 6 months of age.

The main purpose of this study is to evaluate immune persistence at 30 and 36 Months of Age and Pertussis Breakthrough Infections between 19 and 36 Months of Age following two regiments of DTaP-IPV/Hib Pentavalent Vaccine in Healthy 2-Month-Old Infants and Children in China.