RecruitingPhase 3

A Study to Evaluate 20vPnC in Healthy Chinese Infants

China1,250 participantsStarted 2026-07-25

Plain-language summary

The purpose of this study is to evaluate a study vaccine called 20-valent pneumococcal conjugate vaccine (20vPnC). The study will assess whether the study vaccine is safe to use in healthy infants. It will also evaluate if the study vaccine can help the body make antibodies (known as immune response). These antibodies help protect against 20 types of pneumococcal bacteria. The study will compare 20vPnC with 13vPnC (control vaccine), which is approved for use in infants. The study is seeking participants who: * Are healthy infants * Aged 42 to 98 days of age at the time of consent. Infants will receive either 20vPnC or 13vPnC. Doses will be given at approximately 2, 4, and 6 months of age (Doses 1 through 3). A fourth dose will be given at 12 to 15 months of age. Infants will receive the same vaccine (20vPnC or 13vPnC) for all 4 doses. The total time of the study will be about 16 to 19 months. A subset of infants will be asked to stay in the study for longer.

Who can participate

Age range

42 Days – 98 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.

Key Inclusion Criteria: \- Healthy male or female infants born at ≥37 weeks of gestation and who are approximately 2 months of age (≥42 to ≤98 days) at the time of consent (the day of birth is considered Day 1 of life) will be enrolled. Key Exclusion Criteria: * history of a severe adverse reaction associated with a vaccine and/or severe allergic reactions to any component of the study intervention. * significant neurological disorder or history of seizure or significant stable or evolving disorders. * major known congenital malformation or serious chronic disorder. * history of microbiologically proven invasive disease caused by S. pneumoniae. * known or suspected immunodeficiency or other conditions associated with immunosuppression. * previous vaccination with any licensed or investigational pneumococcal vaccine or planned receipt through study participation.

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.

What they're measuring

Percentage of participants reporting prespecified local reactions

Timeframe: From Day 1 (the day of vaccination) through Day 7 following Vaccinations 1, 2, 3, and 4

Percentage of participants reporting prespecified systemic events

Timeframe: From Day 1 (the day of vaccination) through Day 7 following Vaccinations 1, 2, 3, and 4

Percentage of participants reporting Adverse Events (AEs) from the first study vaccination through 1 month following the third study vaccination.

Timeframe: From the first study vaccination to 1 month after the third study vaccination

Percentage of participants reporting AEs from the fourth study vaccination to 1 month following the fourth study vaccination.

Timeframe: From the fourth study vaccination to 1 month after the fourth study vaccination

Percentage of participants reporting serious adverse events (SAEs) through 6 months post last vaccination

Timeframe: From the first study vaccination to 6 months after the last study vaccination

The percentages of participants with predefined serotype-specific immunoglobulin G (IgG) concentrations in 20vPnC group compared to 13vPnC group at 1 month after Dose 3

Trial details

NCT IDNCT07754539

SponsorPfizer

Sponsor typeINDUSTRY

Study typeINTERVENTIONAL

Primary completion2028-11-30

Contact for this trial

Pfizer CT.gov Call Center

1-800-718-1021 ClinicalTrials.gov_Inquiries@pfizer.com

View on ClinicalTrials.gov More Pneumococcal Diseases trials