This is a 2-staged study. Stage I of this study is designed to compare the immune responses elicited by an infant series (3 doses) of Pentacel™ when given at different times from or concurrently with Prevnar®.~Stage II is designed to describe the immune responses elicited by a 4th dose of Pentacel™ (all antigens) when given at different times from or concurrently with Prevnar®.
This study is designed to evaluate in a controlled manner the effect of Prevnar® on the immune responses of Pentacel™~Primary Objective - Stage I:~To compare the immune responses elicited by an infant series of Pentacel™ when given at different times from or concurrently with a Pneumococcal conjugate vaccine (Prevnar®).~Primary Objective - Stage II:~To compare the immune responses elicited by a 4th dose of Pentacel™ when given at different times from or concurrently with Prevnar®.