The purpose of this study is to learn about the safety of a new pneumococcal vaccine and how the new pneumococcal vaccine helps to fight against germs that can cause pneumonia (lung infections), meningitis (brain infections), and otitis media (ear infections) in infants when compared to the pneumococcal vaccine that is currently in use, 20vPnC (Prevnar 20®). This study will test if the new pneumococcal vaccine is as safe as the one that is currently in use. This new vaccine can possibly provide additional protection against germs that cause pneumococcal disease that are not included in the vaccines that are currently given to infants. Pneumococcal disease includes a variety of infections caused by a specific germ, Streptococcus pneumoniae. There are two groups in this study. All participants will be assigned to one of the two groups. This study is seeking participants who are: \- infants who are about 2 months of age About 2400 infants will be assigned by chance to one of the two groups to receive either PG4 (new vaccine) or 20vPnC (currently in use) into the left thigh muscle at 2, 4, 6, and 12 to 15 months of age. Infants will take part in this study for about 16 to 19 months (about 1 and a half years). During this time, infants will have 6 study clinic visits and 1 phone call. At these study clinic visits, parent(s)/legal guardian(s) will be asked if the infant experienced any side effects. A side effect is an unintentional or unexpected reaction to a vaccine.
Age range
42 Days – 98 Days
Sex
ALL
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AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
Percentage of participants reporting local reactions within 7 days after each dose
Timeframe: Day 7
Percentage of participants reporting systemic events within 7 days after each dose
Timeframe: Day 7
Percentage of participants reporting adverse events (AEs) from Dose 1 to 1 month after Dose 3
Timeframe: Dose 1 to 1 month after Dose 3
Percentage of participants reporting AEs from Dose 4 to 1 month after Dose 4
Timeframe: Dose 4 to 1 month after Dose 4
Percentage of participants reporting serious adverse events (SAEs)
Timeframe: Dose 1 to 6 months after Dose 4
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