A Study to Assess the Safety, Tolerability, and Immunogenicity of 3 Lots of a Multivalent Pneumococcal Conjugate Vaccine Administered to Adults
A PHASE 3, RANDOMIZED, DOUBLE-BLIND TRIAL TO EVALUATE THE SAFETY, TOLERABILITY, AND IMMUNOGENICITY OF 3 LOTS OF A MULTIVALENT PNEUMOCOCCAL CONJUGATE VACCINE IN ADULTS
1 other identifier
interventional
4,670
1 country
36
Brief Summary
The purpose of this study is to provide safety data and demonstrate lot consistency with the PG4 vaccine by evaluating the immunogenicity of 3 different lots of this vaccine. This study will compare a new pneumococcal vaccine with the vaccine currently in use to see if they are similarly safe. It will also compare three batches of the new vaccine to make sure they work the same way. Blood samples will be taken to measure how the body responds to the vaccines. The study will be conducted in the United States. Participants will be assigned to 1 of 4 groups. Group 1: PG4 vaccine lot 1; Group 2: PG4 vaccine lot 2; Group 3: PG4 vaccine lot 3; Group 4: 20vPnC. Within each group, participants will be assigned by chance in a 2:2:2:1 ratio to receive 1 vaccine injection (shot) with either PG4 (new vaccine) lot 1, PG4 lot 2, PG4 Lot 3 or 20vPnC, given in the arm. This means that for every 7 participants, about 2 will receive either PG4 lot 1, lot 2 or lot 3 and about 1 will receive 20vPnC. Each participant will take part in the study for approximately 6 months.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for phase_3
Started Sep 2026
Shorter than P25 for phase_3
36 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
August 26, 2026
CompletedFirst Posted
Study publicly available on registry
August 31, 2026
CompletedStudy Start
First participant enrolled
September 8, 2026
CompletedPrimary Completion
Last participant's last visit for primary outcome
June 7, 2027
ExpectedStudy Completion
Last participant's last visit for all outcomes
June 7, 2027
September 23, 2026
September 1, 2026
9 months
August 26, 2026
September 18, 2026
Conditions
Outcome Measures
Primary Outcomes (5)
Percentage of Participants with Prespecified Local Reactions Within 7 Days After Vaccination
Prompted local reactions after each dose
Within 7 days after Vaccination
Percentage of Participants reporting Prespecified Systemic Events Within 7 Days after Vaccination
Prompted systemic events after each dose
Within 7 days after Vaccination
Percentage of Participants with Adverse Events (AEs)
AEs occurring from Dose 1 to 1 month after the vaccination
From Vaccination to 1 month after Vaccination
Percentage of Participants with Serious Adverse Events (SAEs)
SAEs occurring from Dose 1 to 6 months after the vaccination
From Vaccination to 6 months after Vaccination
OPA geometric mean ratios (GMR) between each pair of PG4 vaccine lots
OPA GMRs between each pair of PG4 vaccine lots at 1 month after vaccination
1 month after Vaccination
Secondary Outcomes (4)
OPA Serotype-specific geometric mean titers (GMT) for PG4 vaccine serotypes
1 month after Vaccination
OPA geometric mean fold rise (GMFR) for PG4 vaccine serotypes
From before vaccination to 1 month after vaccination
Percentages of participants with a ≥4-fold rise in opsonophagocytic activity (OPA) titers
From Vaccination to 6 months after Vaccination
Percentages of participants with OPA titers ≥ lower limit of quantitation (LLOQ)
From before vaccination to 1 month after vaccination
Study Arms (4)
PG4 Vaccine Lot 3
EXPERIMENTALMultivalent Pneumococcal Vaccine
PG4 Vaccine Lot 2
EXPERIMENTALMultivalent Pneumococcal Vaccine
PG4 Vaccine Lot 1
EXPERIMENTALMultivalent Pneumococcal Vaccine
20 Valent Pneumococcal Conjugate Vaccine (20vPnC)
ACTIVE COMPARATOR20 Valent Pneumococcal Conjugate Vaccine
Interventions
Multivalent Pneumococcal Vaccine
20 Valent Pneumococcal Conjugate Vaccine
Eligibility Criteria
You may qualify if:
- Adults 18 through 49 years of age, who have no history of receiving a pneumococcal vaccine after 5 years of age.
You may not qualify if:
- Individuals with a history of severe allergic reactions to a vaccine or its components, serious chronic medical disorders, significant psychiatric conditions, known or suspected immunodeficiency, substance abuse issues, asplenia, bleeding diathesis or prolonged bleeding, a history of a prior confirmed invasive pneumococcal infection, and pregnant or breastfeeding females will be excluded from enrollment in the trial.
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- Pfizerlead
Study Sites (36)
Achieve Clinical Research, LLC d/b/a Accel Research Sites - Birmingham Clinical Research Unit
Birmingham, Alabama, 35216, United States
Orange County Research Center
Lake Forest, California, 92630, United States
Diablo Clinical Research, LLC dba Flourish Research
Walnut Creek, California, 94598, United States
Clinical Research Consulting
Milford, Connecticut, 06460, United States
Suncoast Research Associates
Doral, Florida, 33172, United States
Research Centers of America
Hollywood, Florida, 33024, United States
East Coast Institute for Research, LLC
Jacksonville, Florida, 32216, United States
Entrust Clinical Research
Miami, Florida, 33176, United States
Palm Springs Community Health Center
Miami Lakes, Florida, 33014, United States
Indago Research and Health Center, Inc.
Miami Lakes, Florida, 33016, United States
Innovation Medical Research, LLC
Palmetto Bay, Florida, 33157, United States
Palm Beach Research Center
West Palm Beach, Florida, 33409, United States
Javara Inc.
Fayetteville, Georgia, 30214, United States
Clinical Research Atlanta
Stockbridge, Georgia, 30281, United States
East-West Medical Research Institute
Honolulu, Hawaii, 96814, United States
DM Clinical Research
Melrose Park, Illinois, 60160, United States
Velocity Clinical Research, Sioux City
Sioux City, Iowa, 51106, United States
Henry Ford St. John Hospital - Thomas Mackey Center for Infectious Disease Research
Grosse Pointe Woods, Michigan, 48236, United States
Clinical Research Professionals
Chesterfield, Missouri, 63005, United States
Bio-Kinetic Clinical Applications, LLC dba QPS-MO
Springfield, Missouri, 65802, United States
Bio-Kinetic Clinical Applications, LLC dba QPS-MO-Screening and Recruitment Center
Springfield, Missouri, 65807, United States
Sundance Clinical Research, LLC
St Louis, Missouri, 63141, United States
Velocity Clinical Research, Grand Island
Grand Island, Nebraska, 68803, United States
South Jersey Infectious Disease
Somers Point, New Jersey, 08244, United States
Accellacare - Wilmington
Wilmington, North Carolina, 28401, United States
Cincinnati Children's Hospital Medical Center Investigational Drug Services
Cincinnati, Ohio, 45206, United States
Cincinnati Children's Hospital Medical Center Vaccine Research Center
Cincinnati, Ohio, 45206, United States
CTI Clinical Research Center
Cincinnati, Ohio, 45212, United States
Clinical Trials of South Carolina
Moncks Corner, South Carolina, 29461, United States
TMA Headlands LLC (d/b/a Trial Management Associates)
Myrtle Beach, South Carolina, 29572, United States
Coastal Carolina Research Center, LLC
North Charleston, South Carolina, 29405, United States
SMS Clinical Research LLC
Mesquite, Texas, 75149, United States
DM Clinical Research - Sugar Land
Sugar Land, Texas, 77478, United States
DM Clinical Research
Tomball, Texas, 77375, United States
J. Lewis Research, Inc. / Foothill Family Clinic
Salt Lake City, Utah, 84109, United States
J. Lewis Research, Inc. / Foothill Family Clinic South
Salt Lake City, Utah, 84121, United States
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, INVESTIGATOR, OUTCOMES ASSESSOR
- Purpose
- PREVENTION
- Intervention Model
- PARALLEL
- Sponsor Type
- INDUSTRY
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
August 26, 2026
First Posted
August 31, 2026
Study Start
September 8, 2026
Primary Completion (Estimated)
June 7, 2027
Study Completion (Estimated)
June 7, 2027
Last Updated
September 23, 2026
Record last verified: 2026-09
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.