A Study to Learn About How a New Pneumococcal Vaccine Works in Adults
A PHASE 1, RANDOMIZED, DOUBLE-BLIND, SPONSOR-OPEN STUDY TO DESCRIBE THE SAFETY AND TOLERABILITY OF A MULTIVALENT PNEUMOCOCCAL CONJUGATE VACCINE IN ADULTS
1 other identifier
interventional
380
1 country
19
Brief Summary
The purpose of this study is to learn about the safety and tolerability of a pneumococcal vaccine in adults. Participants will receive either:
- an experimental PG4 vaccine
- a PG4 vaccine comparator
- a standard 20vPnC vaccine comparator
- placebo. A placebo does not have any medicine in it but looks just like the study medicine. Participants will take part in this study for up to 18 months depending on which group they are assigned to. During this time, the participants will receive up to two doses of study vaccine or comparator and take part in follow-up visits. At these clinic visits, participants will be asked if any side effects were experienced. The participants will also have to give blood samples during clinic visits.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for phase_1
Started Jul 2025
Typical duration for phase_1
19 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
Click on a node to explore related trials.
Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
July 18, 2025
CompletedStudy Start
First participant enrolled
July 22, 2025
CompletedFirst Posted
Study publicly available on registry
July 25, 2025
CompletedPrimary Completion
Last participant's last visit for primary outcome
October 21, 2027
ExpectedStudy Completion
Last participant's last visit for all outcomes
October 21, 2027
April 8, 2026
April 1, 2026
2.2 years
July 18, 2025
April 2, 2026
Conditions
Outcome Measures
Primary Outcomes (6)
Percentage of participants reporting prespecified local reactions after each dose.
Prespecified local reactions (redness, swelling, and pain at the injection site) occurring within 7 days of each dose administered in the study.
Within 7 days after each study intervention.
Percentage of participants reporting prespecified systemic reactions after each dose.
Prespecified systemic reactions (fever, vomiting, diarrhea, headache, fatigue, muscle pain, and joint pain) occurring within 7 days of each dose administered in the study.
Within 7 days after each study intervention.
Percentage of participants reporting adverse events.
Adverse Events (AEs) occurring from Dose 1 through 1 month after the last vaccination
From signing of the ICD to 1 month after last study intervention.
Percentage of participants reporting serious adverse events.
Serious Adverse Events (SAEs) occurring from Dose 1 through 6 months after the last vaccination.
From signing of the ICD to 6 months after the last study intervention.
Percentage of participants reporting serious adverse events.
Serious Adverse Events (SAEs) occurring from Dose 1 through 12 months after the last vaccination.
From signing of the ICD to 12 months after the last study intervention.
Percentage of participants with abnormal hematology and chemistry laboratory values.
Any abnormal hematology or chemistry laboratory values as compared to baseline within 2 weeks after each study intervention.
Within 2 weeks after each study intervention.
Study Arms (12)
PG4 vaccine with low dose adjuvant PA-001; dose schedule 1
EXPERIMENTALPG4 vaccine with low dose adjuvant PA-001; dose schedule 2
EXPERIMENTALPG4 vaccine with low dose adjuvant PA-002; dose schedule 1
EXPERIMENTALPG4 vaccine with low dose adjuvant PA-002; dose schedule 2
EXPERIMENTALPG4 vaccine with high dose adjuvant PA-001; dose schedule 1
EXPERIMENTALPG4 vaccine with high dose adjuvant PA-001; dose schedule 2
EXPERIMENTALPG4 vaccine with high dose adjuvant PA-002; dose schedule 1
EXPERIMENTALPG4 vaccine with high dose adjuvant PA-002; dose schedule 2
EXPERIMENTALPG4 vaccine; dose schedule 1
ACTIVE COMPARATORPG4 vaccine; dose schedule 2
ACTIVE COMPARATOR20vPnC; dose schedule 1
ACTIVE COMPARATOR20vPnC; dose schedule 2
ACTIVE COMPARATORInterventions
Multivalent pneumococcal conjugate vaccine
Multivalent pneumococcal conjugate vaccine
Multivalent pneumococcal conjugate vaccine
Multivalent pneumococcal conjugate vaccine
(20vPnC)
Placebo
Multivalent pneumococcal conjugate vaccine
Eligibility Criteria
You may qualify if:
- Participants either with no history of ever receiving a pneumococcal vaccine or who have received a pneumococcal vaccine more than 5 years prior to vaccination in this study
You may not qualify if:
- Participants with a history of microbiologically proven invasive disease caused by S pneumoniae.
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- Pfizerlead
Study Sites (19)
Orange County Research Center
Lake Forest, California, 92630, United States
Peninsula Research Associates
Rolling Hills Estates, California, 90274, United States
Finlay Medical Research
Greenacres City, Florida, 33467, United States
Indago Research & Health Center, Inc
Hialeah, Florida, 33012, United States
Johnson County Clinical Trials
Lenexa, Kansas, 66219, 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
Velocity Clinical Research, Omaha
Omaha, Nebraska, 68134, United States
Upstate Global Health Institute
East Syracuse, New York, 13057, United States
NYU Langone Health
New York, New York, 10016, United States
Duke Vaccine and Trials Unit
Durham, North Carolina, 27703, United States
CTI Clinical Research Center
Cincinnati, Ohio, 45212, United States
Headlands Horizons, LLC dba Headlands Research-Brownsville
Brownsville, Texas, 78526, United States
Valley Regional Medical Center
Brownsville, Texas, 78526, United States
LabCorp
Houston, Texas, 77064, United States
IMA Clinical Research San Antonio
San Antonio, Texas, 78229, United States
Dynamed Clinical Research, LP d/b/a 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
Interventions
Intervention Hierarchy (Ancestors)
Study Officials
- STUDY DIRECTOR
Pfizer CT.gov Call Center
Pfizer
Study Design
- Study Type
- interventional
- Phase
- phase 1
- Allocation
- RANDOMIZED
- Masking
- DOUBLE
- Who Masked
- PARTICIPANT, INVESTIGATOR
- Purpose
- PREVENTION
- Intervention Model
- PARALLEL
- Sponsor Type
- INDUSTRY
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
July 18, 2025
First Posted
July 25, 2025
Study Start
July 22, 2025
Primary Completion (Estimated)
October 21, 2027
Study Completion (Estimated)
October 21, 2027
Last Updated
April 8, 2026
Record last verified: 2026-04
Data Sharing
- IPD Sharing
- Will not 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.