A Study to Learn About the Safety and Immune Response of a New Pneumococcal Vaccine in Adults

A Phase 1/2, Randomized, Double-Blind Trial of the Safety and Immunogenicity of a Multivalent Pneumococcal Conjugate Vaccine in Adults 18 Years of Age and Older

The purpose of this study is to learn about the safety and immune effects of a pneumococcal vaccine in adults. This vaccine can possibly provide protection against further pneumococcal disease.

This study will happen in 4 stages: Stage 1 is seeking participants who are between 18 years to 49 years of age. The participants will receive 1 of 2 pneumococcal vaccine candidates (different formulations) or 20vPnC (Prevnar 20) as a single shot given into the upper arm muscle.

Stage 2 will begin after participants have completed Stage 1, and a pneumococcal vaccine candidate has been decided.

Stage 2 is seeking participants who are adults 50 years of age and older. The participants will receive the chosen pneumococcal vaccine candidate from Stage 1 or 20vPnC (Prevnar 20). The vaccines will be given as a single shot into the upper arm muscle.

Stage 3 is seeking participants who are adults 50 years of age and older. The participants will receive the chosen pneumococcal vaccine candidate from Stage 1 or a licensed pneumococcal comparator vaccine. The vaccines will be given as a single shot into the upper arm muscle.

Stage 4 is seeking participants who are adults 50 years of age and older. The participants will receive either one of three pneumococcal vaccine candidates or one of two licensed pneumococcal comparator vaccines. The vaccines will be given as a single shot into the upper arm muscle.

Participants will take part in this study for about 6 months for Stage 1, Stage 3, and Stage 4 and 12 months for Stage 2. During this time participants will have from 2 to 4 clinic visits and 1 phone visit. At these clinic visits, participants will be asked if any side effects were experienced. The participants will also have to give blood samples during these clinic visits.

Study Overview

• Status: Active, not recruiting
• Conditions: Pneumococcal Disease
• Intervention / Treatment: Biological: 20-valent pneumococcal conjugate vaccine (20vPnC); Biological: Licensed pneumococcal comparator vaccine; Biological: Multivalent Pneumococcal Vaccine - Formulation 1; Biological: Multivalent Pneumococcal Vaccine - Formulation 2; Biological: Multivalent Pneumococcal Vaccine - Formulation 3; Biological: Multivalent Pneumococcal Vaccine - Formulation 4

• Study Type: Interventional
• Enrollment (Actual): 558
• Phase: Phase 2; Phase 1

Contacts and Locations

Study Locations

• United States
  • Florida
    • Doral, Florida, United States, 33172
      • Alliance for Multispecialty Research, LLC
    • Hialeah, Florida, United States, 33012
      • Indago Research & Health Center, Inc
  • Georgia
    • Stockbridge, Georgia, United States, 30281
      • Clinical Research Atlanta
  • Illinois
    • Peoria, Illinois, United States, 61614
      • Optimal Research
  • Louisiana
    • New Orleans, Louisiana, United States, 70119
      • Alliance for Multispecialty Research, LLC
  • Michigan
    • Southfield, Michigan, United States, 48034
      • Headlands Research - Detroit
  • New York
    • Rochester, New York, United States, 14609
      • Rochester Clinical Research, LLC
  • North Carolina
    • Wilmington, North Carolina, United States, 28401
      • Accellacare - Wilmington
  • Tennessee
    • Knoxville, Tennessee, United States, 37909
      • AMR Clinical
    • Knoxville, Tennessee, United States, 37920
      • AMR Clinical
  • Texas
    • Brownsville, Texas, United States, 78526
      • Headlands Horizons LLC
    • Houston, Texas, United States, 77065
      • DM Clinical Research- Cyfair
    • San Antonio, Texas, United States, 78229
      • IMA Clinical Research San Antonio
    • San Antonio, Texas, United States, 78229
      • Clinical Trials of Texas, LLC dba Flourish Research
    • Sugar Land, Texas, United States, 77478
      • Dynamed Clinical Research, LP d/b/a DM Clinical Research
    • Tomball, Texas, United States, 77375
      • DM Clinical Research
    • Tomball, Texas, United States, 77375
      • Dynamed Clinical Research, LP d/b/a DM Clinical Research
  • Utah
    • Salt Lake City, Utah, United States, 84109
      • J. Lewis Research, Inc. / Foothill Family Clinic

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Male or female participants ≥18 to<50 years of age (Stage 1) and ≥50 years of age (Stage 2, Stage 3, and Stage 4) at the time of consent
• Adults determined by clinical assessment to be eligible for the study, including adults with preexisting stable disease within 12 weeks before receipt of study intervention
• Participants willing to use acceptable contraception for at least 28 days after study intervention; female participants not of childbearing potential; male participants unable to father children
• Phase 1 (Stage 1): Adults 18 through 49 years of age with no history of ever receiving a pneumococcal vaccine (ie, pneumococcal vaccine-naïve)
• Phase 2 (Stages 2, 3, and 4): Adults ≥50 through 64 years of age with no history of ever receiving a pneumococcal vaccine (ie, pneumococcal vaccine-naïve) and adults 65 years of age and older with either no history of ever receiving a pneumococcal vaccine or who received PPSV23 >5 years prior to the first vaccination in this study (ie, experienced)

Exclusion Criteria:

• History of severe adverse reaction associated with a vaccine and/or severe allergic reaction to any component in pneumococcal conjugate vaccines and any other diphtheria toxoid-containing vaccine
• Serious chronic disorder that in the investigator's opinion would make the participant inappropriate for entry into the study
• Medical or psychiatric condition (recent or active suicidal ideation/behavior or laboratory abnormality) that may increase risk of study participation or make participant inappropriate for the study
• Known or suspected immunodeficiency or other conditions associated with immunosuppression
• Planned receipt of any licensed or investigational pneumococcal vaccine, or planned receipt of any licensed or investigational pneumococcal vaccine through study participation
• Receipt of any inactivated or otherwise nonlive vaccine within 14 days or any live vaccine within 28 days before administration of study intervention

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

6

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Phase 1 (Stage 1) and Phase 2 (Stage 2): 20-valent pneumococcal conjugate vaccine (20vPnC); Participants to receive a single injection of 20vPnC.	Biological: 20-valent pneumococcal conjugate vaccine (20vPnC); 20-valent pneumococcal conjugate vaccine (20vPnC); Other Names: Prevnar 20
Active Comparator: Phase 2 (Stage 3): a licensed pneumococcal comparator vaccine; Participants to receive a single injection of a licensed pneumococcal comparator vaccine.	Biological: Licensed pneumococcal comparator vaccine; A licensed pneumococcal comparator vaccine
Experimental: Phase 1 (Stage 1): Multivalent Pneumococcal Vaccine - Formulation 1; Participants to receive a single injection of Multivalent Pneumococcal Vaccine - Formulation 1. This is a possible candidate for continuation in Phase 2 (Stage 2, 3, and 4).	Biological: Multivalent Pneumococcal Vaccine - Formulation 1; Multivalent pneumococcal conjugate vaccine. This is a possible candidate for continuation in Phase 2 (Stages 2, 3, and 4).
Experimental: Phase 1 (Stage 1): Multivalent Pneumococcal Vaccine - Formulation 2; Participants to receive a single injection of Multivalent Pneumococcal Vaccine - Formulation 2. This is a possible candidate for continuation in Phase 2 (Stage 2, 3, and 4).	Biological: Multivalent Pneumococcal Vaccine - Formulation 2; Multivalent pneumococcal conjugate vaccine. This is a possible candidate for continuation in Phase 2 (Stages 2, 3, and 4).
Experimental: Phase 2 (Stage 4): Multivalent Pneumococcal Vaccine - Formulation 3; Participants to receive a single injection of Multivalent Pneumococcal Vaccine - Formulation 3.	Biological: Multivalent Pneumococcal Vaccine - Formulation 3; Multivalent pneumococcal conjugate vaccine
Experimental: Phase 2 (Stage 4): Multivalent Pneumococcal Vaccine - Formulation 4; Participants to receive a single injection of Multivalent Pneumococcal Vaccine - Formulation 4.	Biological: Multivalent Pneumococcal Vaccine - Formulation 4; Multivalent pneumococcal conjugate vaccine

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percentage of participants reporting prespecified local reactions within 7 days after vaccination	Prespecified local reactions (redness, swelling, and pain at the injection site) after vaccination	7 days
Percentage of participants reporting prespecified systemic events within 7 days after vaccination	Prespecified systemic events (fever, headache, fatigue, muscle pain, and joint pain) after vaccination	7 days
Percentage of participants reporting Adverse Events (AEs) within 1 month after vaccination	Adverse events occurring within 1 month after vaccination	1 month
Percentage of participants reporting Serious Adverse Events (SAEs) within 6 months after vaccination	SAEs occurring within 6 months after vaccination	6 months
Phase 2 (Stage 2) Only: Percentage of participants reporting related Serious Adverse Events (SAEs) through 12 months after vaccination	Related SAEs occurring through 12 months after vaccination	12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Phase 1 (Stage 1) and Phase 2 (Stage 2) Only: Pneumococcal opsonophagocytic activity (OPA) geometric mean titers (GMTs)	Pneumococcal OPA GMTs 1 month after vaccination	1 month after vaccination

Collaborators and Investigators

• Sponsor: Pfizer
• Investigators: Study Director: Pfizer CT.gov Call Center, Pfizer

Publications and helpful links

Helpful Links

• To obtain contact information for a study center near you, click here.

Study record dates

Study Major Dates

• Study Start (Actual): December 20, 2023
• Primary Completion (Estimated): May 23, 2026
• Study Completion (Estimated): May 23, 2026

Study Registration Dates

• First Submitted: December 8, 2023
• First Submitted That Met QC Criteria: December 21, 2023
• First Posted (Actual): December 26, 2023

Study Record Updates

• Last Update Posted (Estimated): October 14, 2025
• Last Update Submitted That Met QC Criteria: October 9, 2025
• Last Verified: October 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Infections; Gram-Positive Bacterial Infections; Bacterial Infections; Bacterial Infections and Mycoses; Streptococcal Infections; Pneumococcal Infections; Immunologic Factors; Physiological Effects of Drugs; Heptavalent Pneumococcal Conjugate Vaccine; Vaccines
• Other Study ID Numbers: C4931001; NCT06182124 (Registry Identifier: ClinicalTrials.gov)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: 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.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No