Recruiting

Phase 3

PG4Study to Learn About Safety, Tolerability, and Immune Response of a Catch-up Pneumococcal Vaccine in Children and Adolescents

Sponsor:

Pfizer

Code:

NCT07660198

Conditions

Pneumococcal Disease

Eligibility Criteria

Sex: All

Age: 1 - 17

Healthy Volunteers: Accepted

Interventions

PG4

20-valent pneumococcal conjugate vaccine (20vPnC)

Study Details

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.

Conditions

Pneumococcal Disease

Study ID

NCT07660198

Start date

Jun 15, 2026

Status verified date

Aug, 2026

Completion date

Dec 2, 2027

Anticipated

Primary completion date

Dec 2, 2027

Anticipated

Eligibility Criteria

Sex: All

Age: 1 - 17

Healthy Volunteers: Accepted

Inclusion Criteria:

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.

Exclusion Criteria:

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

Study Design

Enrollment

1200 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Prevention

Interventions and Outcome Measures

Arms

experimental: PG4 (intramuscular)

Multivalent Pneumococcal vaccine

active comparator: 20-valent pneumococcal conjugate vaccine (20vPnC) (intramuscular)

20-valent pneumococcal conjugate vaccine (20vPnC)

Interventions

PG4

Multivalent Pneumococcal Vaccine

20-valent pneumococcal conjugate vaccine (20vPnC)

Primary outcome measure

Percentage of Participants With Local Reactions Within 7 Days After Vaccination [ Time Frame: Within 7 days after Vaccination ]
Percentage of Participants With Systemic Events Within 7 Days after Vaccination [ Time Frame: Within 7 days after Vaccination ]
Percentage of Participants With Adverse Events (AEs) [ Time Frame: From Vaccination to 1 month after Vaccination ]
Percentage of Participants With Serious Adverse Events (SAEs) [ Time Frame: From Vaccination to 6 months after Vaccination ]
GMCs of serotype-specific IgG concentrations [ Time Frame: 1 month after vaccination ]
GMTs of serotype-specific OPA titers [ Time Frame: 1 month after vaccination ]

Central Contacts and Locations

Central contacts

Pfizer CT.gov Call Center

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

Locations

Alabama Clinical Therapeutics, LLC Birmingham Pediatric Associates

Recruiting

Birmingham, Alabama, United States, 35205

UAB Child Health Research Unit (CHRU)

Recruiting

Birmingham, Alabama, United States, 35233

Lakeview Clinical Research, LLC

Recruiting

Guntersville, Alabama, United States, 35976

Apex Research Group

Recruiting

Fair Oaks, California, United States, 95628

Orange County Research Institute

Recruiting

Ontario, California, United States, 91762

Children's Hospital Colorado

Recruiting

Aurora, Colorado, United States, 80045

Riveldi and Associates

Recruiting

Miami Lakes, Florida, United States, 33014

Indago Research & Health Center, Inc

Recruiting

Miami Lakes, Florida, United States, 33016

Medical Research Partners

Recruiting

Ammon, Idaho, United States, 83406

Bingham Memorial Hospital

Recruiting

Blackfoot, Idaho, United States, 83221

ASR, LLC

Recruiting

Boise, Idaho, United States, 83702

Kentucky Pediatric/ Adult Research

Recruiting

Bardstown, Kentucky, United States, 40004

Avacare

Recruiting

Covington, Louisiana, United States, 70433

Velocity Clinical Research, Lafayette

Recruiting

Lafayette, Louisiana, United States, 70508

LSU Health Shreveport Clinical Trials Office

Recruiting

Shreveport, Louisiana, United States, 71101

Ochsner/LSU Health Shreveport - Progressive Pediatrics

Recruiting

Shreveport, Louisiana, United States, 71101

Ochsner LSU Health Shreveport Ambulatory Care Center

Recruiting

Shreveport, Louisiana, United States, 71103

Ochsner/LSU Health Shreveport Academic Medical Center

Recruiting

Shreveport, Louisiana, United States, 71103

Pediatric Associates of Fall River

Recruiting

Fall River, Massachusetts, United States, 02721

Michigan Center of Medical Research

Recruiting

Bingham Farms, Michigan, United States, 48025

Clinical Research Institute, Inc.

Recruiting

Minneapolis, Minnesota, United States, 55402

Midwest Children's Health Research Institute

Recruiting

Lincoln, Nebraska, United States, 68504

Midwest Children's Health Research Institute

Recruiting

Lincoln, Nebraska, United States, 68505

Midwest Children's Health Research Institute

Recruiting

Lincoln, Nebraska, United States, 68516

Midwest Children's Health Research Institute

Recruiting

Lincoln, Nebraska, United States, 68522

Child Health Care Associates

Recruiting

East Syracuse, New York, United States, 13057

Corning Center for Clinical Research

Recruiting

Horseheads, New York, United States, 14845

University of Rochester Medical Center

Recruiting

Rochester, New York, United States, 14642

Cincinnati Children's Hospital Medical Center Investigational Drug Services

Recruiting

Cincinnati, Ohio, United States, 45206

Cincinnati Children's Hospital Medical Center Vaccine Research Center

Recruiting

Cincinnati, Ohio, United States, 45206

Pediatric Associates of Mt. Carmel

Recruiting

Cincinnati, Ohio, United States, 45245

Dayton Clinical Research

Recruiting

Dayton, Ohio, United States, 45409

Senders Pediatrics

Recruiting

South Euclid, Ohio, United States, 44121

Tribe Clinical Research LLC. at Parkside Pediatrics Five Forks

Recruiting

Simpsonville, South Carolina, United States, 29681

Pediatric Clinical Trials of Tennessee, LLC

Recruiting

Tullahoma, Tennessee, United States, 37388

Driscoll Children's Hosptial

Recruiting

Corpus Christi, Texas, United States, 78411

Mercury Clinical Research (Administrative Office)

Recruiting

Houston, Texas, United States, 77054

Mercury Clinical Research - Administrative Office

Recruiting

Houston, Texas, United States, 77054

Kool Kids Pediatrics

Recruiting

Houston, Texas, United States, 77065

Mercury Clinical Research - Sunrise Pediatrics

Recruiting

Houston, Texas, United States, 77077

Mercury Clinical Research - MD Kids Pediatrics

Recruiting

Houston, Texas, United States, 77087

Neutra Life Sciences

Recruiting

Houston, Texas, United States, 77402

University of Texas Medical Branch,

Recruiting

League City, Texas, United States, 77573

Pediatric Center- Neutra Life Sciences

Recruiting

Richmond, Texas, United States, 77469

Sun Research Institute

Recruiting

San Antonio, Texas, United States, 78215

Victoria Clinical Research Group

Recruiting

Victoria, Texas, United States, 77901

Tanner Clinic - Layton Parkway

Recruiting

Layton, Utah, United States, 84041

Tanner Clinic

Recruiting

Layton, Utah, United States, 84041

AMR Clinical

Recruiting

Provo, Utah, United States, 84604

AMR Clinical

Recruiting

Syracuse, Utah, United States, 84075

Velocity Clinical Research, Salt Lake City

Recruiting

West Jordan, Utah, United States, 84088

Pediatric Research of Charlottesville, LLC

Recruiting

Charlottesville, Virginia, United States, 22902

Clinical Research Partners, LLC

Recruiting

Richmond, Virginia, United States, 23226

More Information

Sponsor

Pfizer

Last update posted

Aug 31, 2026

Last verified

Aug, 2026

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-08. This information was provided to ClinicalTrials.gov by Pfizer on 2026-08-31.