Dataset from A Study to Evaluate the Long-term Antibody Persistence at 1, 3 & 5 Years After the Administration of a Fourth Dose of Hib-MenCY-TT Vaccine Compared to ActHIB in Subjects Boosted in a Previous Study.

This study is evaluating antibody persistence at 1, 3 & 5 years post-fourth dose (i.e., at 2, 4 & 6 years of age, respectively) in subjects vaccinated in a previous study. This protocol posting deals with objectives & outcome measures of the extension phase at years 1, 3 and 5. The objectives & outcome measures of the first four doses are presented in a separate protocol posting (NCT00129129). This protocol posting has been amended in order to comply with the FDA Amendment Act of September 26, 2007.