Study to Learn About Safety, Tolerability, and Immune Response of a Catch-up Pneumococcal Vaccine in Children and Adolescents
A PHASE 3, RANDOMIZED DOUBLE-BLIND TRIAL TO EVALUATE THE SAFETY, TOLERABILITY, AND IMMUNOGENICITY OF A CATCH-UP VACCINATION REGIMEN OF A MULTIVALENT PNEUMOCOCCAL CONJUGATE VACCINE IN HEALTHY CHILDREN AND ADOLESCENTS
2 other identifiers
interventional
1,200
2 countries
44
Brief Summary
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 children 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. 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 children. Pneumococcal disease includes a variety of infections caused by a specific germ, Streptococcus pneumoniae This study is seeking participants who:
- Are children aged 15 months to 18 years.
- May or may not have received any doses of pneumococcal conjugate vaccine (PCV) in the past. The study will be conducted in the United States, Puerto Rico, and other countries. Participants will be assigned to 1 of 3 groups based on age: Group 1: 15 months to less than 2 years (about 300 participants) Group 2: 2 years to less than 5 years (about 300 participants) Group 3: 5 years to less than 18 years (about 600 participants) Within each group, participants will be assigned by chance in a 2:1 ratio to receive 1 vaccine injection (shot) with either PG4 (new vaccine) or 20vPnC, given in the arm or thigh. This means that for every 3 participants, about 2 will receive PG4 and about 1 will receive 20vPnC. Each participant will take part in the study for approximately 6 months. During this time, each participant will visit a clinic 2 times (visit 1 for vaccination and visit 2 to follow up) and will be contacted via telephone once (for a 6 month follow up). At the study clinic visits, participants will have their blood drawn and be asked if they have experienced any side effects. A side effect is an unintentional or unexpected reaction to a vaccine. During the 6-month follow-up contact, participants will be asked about any further side effects.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for phase_3
Started Jun 2026
44 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
June 15, 2026
CompletedStudy Start
First participant enrolled
June 15, 2026
CompletedFirst Posted
Study publicly available on registry
June 22, 2026
CompletedPrimary Completion
Last participant's last visit for primary outcome
December 2, 2027
ExpectedStudy Completion
Last participant's last visit for all outcomes
December 2, 2027
July 9, 2026
July 1, 2026
1.5 years
June 15, 2026
July 7, 2026
Conditions
Outcome Measures
Primary Outcomes (6)
Percentage of Participants With Local Reactions Within 7 Days After Vaccination
Within 7 days after Vaccination
Percentage of Participants With Systemic Events Within 7 Days after Vaccination
Within 7 days after Vaccination
Percentage of Participants With Adverse Events (AEs)
From Vaccination to 1 month after Vaccination
Percentage of Participants With Serious Adverse Events (SAEs)
From Vaccination to 6 months after Vaccination
GMCs of serotype-specific IgG concentrations
1 month after vaccination
GMTs of serotype-specific OPA titers
1 month after vaccination
Secondary Outcomes (4)
Percentage of participants with predefined serotype-specific IgG concentrations
1 month after vaccination
IgG GMFRs
1 month after vaccination
Percentage of participants with a ≥4-fold rise in serotype-specific OPA titers
before to 1 month after vaccination
OPA GMFRs
before to 1 month after vaccination
Study Arms (2)
PG4 (intramuscular)
EXPERIMENTALMultivalent Pneumococcal vaccine
20-valent pneumococcal conjugate vaccine (20vPnC) (intramuscular)
ACTIVE COMPARATOR20-valent pneumococcal conjugate vaccine (20vPnC)
Interventions
20-valent pneumococcal conjugate vaccine (20vPnC)
Eligibility Criteria
You may qualify if:
- Cohort 1 (Participants ≥15 Months to \<2 Years of Age) Healthy toddlers and children ≥15 months to \<2 years of age with documentation of prior receipt of PCV.
- Cohort 2 (Participants ≥2 Years to \<5 Years of Age) Healthy toddlers and children ≥2 years to \<5 years of age with documentation of prior receipt of PCV if applicable.
- Cohort 3 (Participants ≥5 Years to \<18 Years of Age) Healthy children ≥5 years to \<18 years of age with documentation of prior receipt of PCV (if applicable). A negative urine pregnancy test is required for individuals of childbearing potential (IOCBP). IOCBP or participants able to father must also agree to use a highly effective method of birth control.
You may not qualify if:
- All Cohorts (Participants ≥15 Months to \<18 Years of Age)
- Children with significant medical, psychiatric, or neurological conditions (eg, immunodeficiency or history of seizure); or a history of confirmed invasive pneumococcal infection in the past will be excluded from enrolment in the trial
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- Pfizerlead
Study Sites (44)
Alabama Clinical Therapeutics, LLC Birmingham Pediatric Associates
Birmingham, Alabama, 35205, United States
Apex Research Group
Fair Oaks, California, 95628, United States
Orange County Research Institute
Ontario, California, 91762, United States
Riveldi and Associates
Miami Lakes, Florida, 33014, United States
Indago Research & Health Center, Inc
Miami Lakes, Florida, 33016, United States
Medical Research Partners
Ammon, Idaho, 83406, United States
Bingham Memorial Hospital
Blackfoot, Idaho, 83221, United States
ASR, LLC
Boise, Idaho, 83702, United States
Kentucky Pediatric/ Adult Research
Bardstown, Kentucky, 40004, United States
Avacare
Covington, Louisiana, 70433, United States
Velocity Clinical Research, Lafayette
Lafayette, Louisiana, 70508, United States
LSU Health Shreveport Clinical Trials Office
Shreveport, Louisiana, 71101, United States
Ochsner/LSU Health Shreveport - Progressive Pediatrics
Shreveport, Louisiana, 71101, United States
Ochsner LSU Health Shreveport Ambulatory Care Center
Shreveport, Louisiana, 71103, United States
Ochsner/LSU Health Shreveport Academic Medical Center
Shreveport, Louisiana, 71103, United States
Pediatric Associates of Fall River
Fall River, Massachusetts, 02721, United States
Michigan Center of Medical Research
Bingham Farms, Michigan, 48025, United States
Clinical Research Institute, Inc.
Minneapolis, Minnesota, 55402, United States
Midwest Children's Health Research Institute
Lincoln, Nebraska, 68504, United States
Midwest Children's Health Research Institute
Lincoln, Nebraska, 68505, United States
Midwest Children's Health Research Institute
Lincoln, Nebraska, 68516, United States
Midwest Children's Health Research Institute
Lincoln, Nebraska, 68522, United States
Child Health Care Associates
East Syracuse, New York, 13057, United States
Corning Center for Clinical Research
Horseheads, New York, 14845, United States
Pediatric Associates of Mt. Carmel
Cincinnati, Ohio, 45245, United States
Dayton Clinical Research
Dayton, Ohio, 45409, United States
Senders Pediatrics
South Euclid, Ohio, 44121, United States
Tribe Clinical Research LLC. at Parkside Pediatrics Five Forks
Simpsonville, South Carolina, 29681, United States
Pediatric Clinical Trials of Tennessee, LLC
Tullahoma, Tennessee, 37388, United States
Mercury Clinical Research (Administrative Office)
Houston, Texas, 77054, United States
Kool Kids Pediatrics
Houston, Texas, 77065, United States
Mercury Clinical Research - Pediatric Associates
Houston, Texas, 77087, United States
Neutra Life Sciences
Houston, Texas, 77402, United States
Pediatric Center- Neutra Life Sciences
Richmond, Texas, 77469, United States
Sun Research Institute
San Antonio, Texas, 78215, United States
Victoria Clinical Research Group
Victoria, Texas, 77901, United States
Tanner Clinic - Layton Parkway
Layton, Utah, 84041, United States
Tanner Clinic
Layton, Utah, 84041, United States
AMR Clinical
Provo, Utah, 84604, United States
AMR Clinical
Syracuse, Utah, 84075, United States
Velocity Clinical Research, Salt Lake City
West Jordan, Utah, 84088, United States
Pediatric Research of Charlottesville, LLC
Charlottesville, Virginia, 22902, United States
Clinical Research Partners, LLC
Richmond, Virginia, 23226, United States
BRCR Global Puerto Rico
San Juan, 00907-1509, Puerto Rico
Related Links
MeSH Terms
Conditions
Condition Hierarchy (Ancestors)
Study Officials
- STUDY DIRECTOR
Pfizer CT.gov Call Center
Pfizer
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- phase 3
- Allocation
- RANDOMIZED
- Masking
- TRIPLE
- Who Masked
- PARTICIPANT, CARE PROVIDER, INVESTIGATOR
- Purpose
- PREVENTION
- Intervention Model
- PARALLEL
- Sponsor Type
- INDUSTRY
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
June 15, 2026
First Posted
June 22, 2026
Study Start
June 15, 2026
Primary Completion (Estimated)
December 2, 2027
Study Completion (Estimated)
December 2, 2027
Last Updated
July 9, 2026
Record last verified: 2026-07
Data Sharing
- IPD Sharing
- Will share
Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical\_trials/trial\_data\_and\_results/data\_requests.