This study is a Phase 3, randomized, modified double-blind study which aims to measure whether PCV21 vaccine (investigational pneumococcal conjugate vaccine) is safe and can help the body to develop germ-fighting agents called "antibodies" (immunogenicity) compared with 15vPCV (Vaxneuvance, licensed pneumococcal conjugate vaccine) when they are administered with routine pediatric vaccines in infants aged from approximately 2 months (42 to 112 days).
The study duration per participant will be up to approximately 20 months. The study vaccines (either PCV21 or 15-valent pneumococcal vaccines) will be administered at approximately 2, 4, and 11 to 15 months of age or at approximately 2, 3, 4, and 11 to 15 months of age (for preterm infants). Routine pediatric vaccines will be given at the same timepoints, as per local practice / recommendations.
• There will be 5 (for full-term infants) or 6 (for preterm infants) study visits:
* Full-term infants: Visit (V)01, V02 separated from V01 by 60 days, V03 separated from V02 by 30 days, V04 at 11 months of age until 15 months of age, V05 separated from V04 by 30 days.
* Preterm infants: Visit (V)01, V02 separated from V01 by 30 days, V03 separated from V02 by 30 days, V04 separated from V03 by 30 days, V05 at 11 months of age until 15 months of age, V06 separated from V05 by 30 days.
Who can participate
Age range
42 Days – 112 Days
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion Criteria:
* Aged 42 to 112 days on the day of inclusion
* Participants who are healthy as determined by medical evaluation including medical history and physical examination
* Born at full term of pregnancy (≥ 37 weeks) and with a birth weight ≥ 2.5 kg or born after a gestation period above 28 (\> 28 weeks) through 36 weeks with a birth weight ≥ 1.5 kg, and in both cases medically stable as assessed by the investigator
Exclusion Criteria: Participants are excluded from the study if any of the following criteria apply:
* Known or suspected congenital or acquired immunodeficiency; or receipt of immunosuppressive therapy, such as anti-cancer chemotherapy or radiation therapy; or long-term systemic corticosteroid therapy
* History of microbiologically confirmed Streptococcus pneumoniae infection or disease
* Any contraindication to the routine pediatric vaccines being administered in the study
* History of seizure or significant stable or progressive neurological disorders such as infantile spasms, inflammatory nervous system diseases, encephalopathy, cerebral palsy
* Known systemic hypersensitivity to any of the study interventions components, or history of a life-threatening reaction to the study interventions used in the study or to a product containing any of the same substances
* Laboratory-confirmed or known thrombocytopenia, as reported by the parent/legally acceptable representative (LAR), contraindicating intramuscular (IM) injection
* Bleeding disorder, or …
Questions worth asking your doctor
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.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
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.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.