Skip to content
Bored Studies
RecruitingAccepts healthy volunteersPhase 3

A Study to Learn About How a New Pneumococcal Vaccine Works in Infants.

Pfizer · NCT07629440

View Study & Apply (opens in a new tab)

Opens the official ClinicalTrials.gov record, with the study team’s contacts. Bored Studies doesn’t enroll anyone.

Key facts

Compensation
Not posted. Ask the study team before screening.
Who can join
Ages 1 mo–7 mo · All sexes
Healthy volunteers
Accepted
Study type
Interventional · Phase 3
Target enrollment
3230
US sites recruiting
106
Study start
May 29, 2026
Record last updated
October 20, 2026

Status re-checked against ClinicalTrials.gov within the last 12 hours.

What the study is about

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. It will also assess how the new vaccine works in comparison to the one that is currently in use when given with other childhood vaccines.

To measure how the new pneumococcal vaccine compares to the current one, blood samples will be used to measure the body's ability to create proteins to fight those germs. 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 three groups in this study. All participants will be assigned to one of the three groups. This study is seeking participants who are:

  • infants who are 2 months of age in Group 1;
  • infants who are 2 to 6 months of age in Groups 2 and 3; and
  • said to be healthy by the study doctor

About 3000 infants will be assigned to Group 1. The infants in this group will have a 1 in 2 chance (50%) of receiving 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.

About 140 infants from outside the United States will be assigned to Group 2. The infants in this group will have a 1 in 2 chance (50%) of receiving either PG4 or 20vPnC into the left thigh muscle at 2 to 6, 3 to 8, 4 to 10, and 12 to 15 months of age.

About 90 infants from outside the United States will be assigned to Group 3. The infants in Group 3 will have a 1 in 3 chance (33%) of receiving either PG4 into the left thigh muscle, PG4 under the skin of the left thigh, or 20vPnC into the left thigh muscle at 2 to 6, 3 to 8, 4 to 10, and 12 to 15 months of age.

Infants in Group 1 will take part in this study for about 16 to 19 months (about 1 and a half years). Infants in Groups 2 and 3 will take part in this study for 12 to 21 months (about 1 to 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. Infants will have 3 blood samples collected.

Being studied: PG4; 20-valent pneumococcal conjugate vaccine (20vPnC)

Conditions: Pneumococcal Disease

Eligibility criteria

Copied from the official record. The study team makes the final decision at screening.

Show full criteria

Inclusion Criteria

  • infants who are 2 months of age in Group 1.
  • infants who are 2 to 6 months of age in Groups 2 and 3.
  • Healthy infants determined by clinical assessment, including medical history and clinical judgment, to be eligible for the study.

Exclusion Criteria

  • History of severe adverse reaction associated with a vaccine and/or severe allergic reaction (eg, anaphylaxis).
  • Major known congenital malformation or serious chronic disorder.
  • Other acute or chronic medical or psychiatric condition or laboratory abnormality that may increase the risk associated with study participation or investigational product administration or may interfere with the interpretation of study results and, in the judgment of the investigator, would make the participant inappropriate for entry into this study.
  • Previous vaccination with any licensed or investigational pneumococcal vaccine, or planned receipt through study participation.

Recruiting US locations

+ 46 more on the official record.

Study contacts (from the official record)

  • Pfizer CT.gov Call Center · 1-800-718-1021 · ClinicalTrials.gov_Inquiries@pfizer.com
All vaccine studies in Alabama →
A Study to Learn About How a New Pneumococcal Vaccine Works in… (NCT07629440) | Bored Studies