Study of Mixed Vaccination Schedules With a 21-valent Pneumococcal Conjugate Vaccine and a 20-valent Pneumococcal Conjugate Vaccine in Healthy Infants From Approximately 2 Months of Age

연구 개요

This study is a Phase 3, randomized, modified double-blind study which aims to measure whether the investigational pneumococcal conjugate vaccine PCV21 is safe and can help the body to develop germ-fighting agents called "antibodies" (immunogenicity) when it is given after 1 dose, 2 doses, or 3 doses of a licensed 20-valent pneumococcal vaccine compared to when 20-valent pneumococcal vaccine is given as a complete series in infants aged from approximately 2 months (42 to 89 days). The study duration per participant will be up to approximately 19 months. The study vaccines (either PCV21 or 20vPCV) will be administered at approximately 2, 4, 6 and 12 to 15 months of age (MoA). Routine pediatric vaccines will be given as per local recommendations. There will be 6 study visits: Visit (V)01, V02 separated from V01 by 60 days, V03 separated from V02 by 60 days, V04 separated from V03 by 30 days, V05 at 12 months of age until 15 months of age, V06 separated from V05 by 30 days.