Study of Mixed Vaccination Schedules With a 21-valent Pneumococcal Conjugate Vaccine and a 20-valent Pneumococcal Conjugate Vaccine in Healthy Infants From Approximately 2 Months of Age

February 12, 2026 updated by: Sanofi

A Phase 3, Randomized, Modified Double-blind, Active-controlled, Parallel-group, 4-arm Study to Investigate the Mixed Vaccination Schedules of a 21-valent Pneumococcal Conjugate Vaccine and a 20-valent Pneumococcal Conjugate Vaccine in Healthy Infants and Toddlers

This study is a Phase 3, randomized, modified double-blind study which aims to measure whether the investigational pneumococcal conjugate vaccine PCV21 is safe and can help the body to develop germ-fighting agents called "antibodies" (immunogenicity) when it is given after 1 dose, 2 doses, or 3 doses of a licensed 20-valent pneumococcal vaccine compared to when 20-valent pneumococcal vaccine is given as a complete series in infants aged from approximately 2 months (42 to 89 days).

The study duration per participant will be up to approximately 19 months. The study vaccines (either PCV21 or 20vPCV) will be administered at approximately 2, 4, 6 and 12 to 15 months of age (MoA). Routine pediatric vaccines will be given as per local recommendations.

There will be 6 study visits:

Visit (V)01, V02 separated from V01 by 60 days, V03 separated from V02 by 60 days, V04 separated from V03 by 30 days, V05 at 12 months of age until 15 months of age, V06 separated from V05 by 30 days.

Study Overview

Status

Active, not recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Actual)

580

Phase

  • Phase 3

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Chile
    • Reg Metropolitana de Santiago
      • Santiago, Reg Metropolitana de Santiago, Chile, 8330034
        • Investigational Site Number : 1520003
      • Santiago, Reg Metropolitana de Santiago, Chile, 8380418
        • Investigational Site Number : 1520002
      • Santiago, Reg Metropolitana de Santiago, Chile, 8880465
        • Investigational Site Number : 1520001
  • Mexico
    • Guanajuato
      • León, Guanajuato, Mexico, 37320
        • Investigational Site Number : 4840003
    • Mexico City
      • Mexico City, Mexico City, Mexico, 04530
        • Investigational Site Number : 4840001
    • Morelos
      • Temixco, Morelos, Mexico, 62587
        • Investigational Site Number : 4840002
      • Tlaltizapán, Morelos, Mexico, 62770
        • Investigational Site Number : 4840004
  • Philippines
      • Cebu City, Philippines, 6000
        • Investigational Site Number : 6080001
      • Quezon City, Philippines, 1100
        • Investigational Site Number : 6080002
      • Quezon City, Philippines, 1121
        • Investigational Site Number : 6080003
  • United States
    • California
      • Los Angeles, California, United States, 90027
        • Kaiser Permanente - Los Angeles Medical Center- Site Number : 8400025
    • Florida
      • Hollywood, Florida, United States, 33021
        • The Medici Medical Research- Site Number : 8400008
      • Miami, Florida, United States, 33135
        • Clinsearch Inc at Dr. Gala, LLC- Site Number : 8400027
      • Miami, Florida, United States, 33173
        • Atlantis Clinical Research- Site Number : 8400009
    • Iowa
      • Sioux City, Iowa, United States, 51106
        • Velocity Clinical Research - Sioux City- Site Number : 8400007
    • Kentucky
      • Lexington, Kentucky, United States, 40517
        • Private Practice - Dr. Michael W. Simon- Site Number : 8400001
    • Louisiana
      • New Orleans, Louisiana, United States, 70119
        • Velocity Clinical Research - New Orleans- Site Number : 8400006
    • New York
      • Cortland, New York, United States, 13045
        • Finger Lakes Medical Research - Cortland- Site Number : 8400022
      • Rochester, New York, United States, 14642
        • University of Rochester Medical Center- Site Number : 8400019
      • Syracuse, New York, United States, 13210
        • SUNY Upstate Medical University - Syracuse- Site Number : 8400015
    • Pennsylvania
      • Hermitage, Pennsylvania, United States, 16148
        • Kid's Way Pediatrics- Site Number : 8400013
    • South Carolina
      • Charleston, South Carolina, United States, 29414
        • Carolina Family Care - Charleston- Site Number : 8400014
    • Texas
      • Burleson, Texas, United States, 76028
        • Helios Clinical Research - BUR PEDI- Site Number : 8400016
      • Euless, Texas, United States, 76040
        • Clinsearch Inc at VAST Clinical Research- Site Number : 8400028
      • Houston, Texas, United States, 77065
        • DM Clinical Research - Houston - Jones Road- Site Number : 8400012
      • League City, Texas, United States, 77555
        • University of Texas Medical Branch at Galveston- Site Number : 8400005
      • Stephenville, Texas, United States, 76401
        • Javara - Privia Medical Group North Texas - Stephenville- Site Number : 8400024

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  • Aged 42 to 89 days on the day of inclusion
  • Participants who are healthy as determined by medical evaluation including medical history and physical examination
  • Born at full term of pregnancy (≥ 37 weeks) and with a birth weight ≥ 2.5 kg or born after a gestation period above 28 (> 28 weeks) through 36 weeks with a birth weight ≥ 1.5 kg, and in both cases medically stable as assessed by the investigator

Exclusion Criteria:

Participants are excluded from the study if any of the following criteria apply:

  • Known or suspected congenital or acquired immunodeficiency; or receipt of immunosuppressive therapy, such as anti-cancer chemotherapy or radiation therapy; or long-term systemic corticosteroid therapy
  • History of microbiologically confirmed Streptococcus pneumoniae infection or disease.
  • History of seizure or significant stable or progressive neurologic disorders such as inflammatory nervous system diseases, encephalopathy, cerebral palsy
  • Known systemic hypersensitivity to any of the study interventions components, or history of a life-threatening reaction to the study interventions used in the study or to a product containing any of the same substances
  • Thrombocytopenia, or known thrombocytopenia, as reported by the parent/legal acceptable representative (LAR), contraindicating intramuscular (IM) injection.
  • Bleeding disorder, or receipt of anticoagulants in the 3 weeks preceding inclusion, contraindicating IM injection
  • Chronic illness that, in the opinion of the investigator, is at a stage where it might interfere with study conduct or completion
  • Moderate or severe acute illness/infection (according to investigator judgment) or febrile illness (temperature ≥ 38.0°C [≥ 100.4°F]) on the day of study intervention administration. A prospective participant should not be included in the study until the condition has resolved or the febrile event has subsided.
  • Previous vaccination against Streptococcus pneumoniae
  • Receipt of immune globulins, blood or blood-derived products since birth
  • Participation at the time of study enrollment (or in the 6 weeks preceding the first study intervention administration) or planned participation during the present study period in another clinical study investigating a vaccine, drug, medical device, or medical procedure

Note: The above information is not intended to contain all considerations relevant to a potential participation in a clinical trial.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

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

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Group 1: 20vPCV-PCV21-PCV21-PCV21
Participants will be administered via intramuscular injection (IM) a 4-dose 20vPCV regimen at approximately 2 MoA, PCV21 at 4 MoA, PCV21 at 6 MoA and PCV21 at 12 to 15 MoA
Biological: PCV21 vaccine
Pharmaceutical form:Suspension for injection-Route of administration:Intramuscular
Other Names:
  • 515
Biological: M-M-R II vaccine
Pharmaceutical form:Powder, lyophilized, for suspension for reconstitution-Route of administration:Subcutaneous or Intramuscular
Other Names:
  • M-M-R™ II
Biological: RotaTeq
Pharmaceutical form:Solution-Route of administration:Oral
Other Names:
  • RotaTeq™
Biological: Vaxelis vaccine
Pharmaceutical form:Suspension for injection-Route of administration:Intramuscular
Other Names:
  • Vaxelis™
Biological: Varivax
Pharmaceutical form:Powder, lyophilized, for suspension for reconstitution-Route of administration:Subcutaneous or Intramuscular
Other Names:
  • Varivax™
Biological: Prevnar 20 vaccine
Pharmaceutical form:Suspension for injection-Route of administration:Intramuscular
Other Names:
  • Prevnar20™
Biological: Rotarix
Pharmaceutical form:Solution-Route of administration:Oral
Other Names:
  • Rotarix™
Biological: Priorix
Pharmaceutical form:Lyophilized, for suspension for reconstitution-Route of administration:Subcutaneous
Other Names:
  • Priorix™
Biological: VAQTA
Pharmaceutical form:Suspension for Injection-Route of administration:Intramuscular
Other Names:
  • VAQTA™
Biological: Havrix
Pharmaceutical form:Suspension for Injection-Route of administration:Intramuscular
Other Names:
  • Havrix™
Experimental: Group 2: 20vPCV-20vPCV-PCV21-PCV21
Participants will be administered via intramuscular injection (IM) a 4-dose 20vPCV regimen at approximately 2 MoA, 20vPCV at 4 MoA, PCV21 at 6 MoA and PCV21 at 12 to 15 MoA
Biological: PCV21 vaccine
Pharmaceutical form:Suspension for injection-Route of administration:Intramuscular
Other Names:
  • 515
Biological: M-M-R II vaccine
Pharmaceutical form:Powder, lyophilized, for suspension for reconstitution-Route of administration:Subcutaneous or Intramuscular
Other Names:
  • M-M-R™ II
Biological: RotaTeq
Pharmaceutical form:Solution-Route of administration:Oral
Other Names:
  • RotaTeq™
Biological: Vaxelis vaccine
Pharmaceutical form:Suspension for injection-Route of administration:Intramuscular
Other Names:
  • Vaxelis™
Biological: Varivax
Pharmaceutical form:Powder, lyophilized, for suspension for reconstitution-Route of administration:Subcutaneous or Intramuscular
Other Names:
  • Varivax™
Biological: Prevnar 20 vaccine
Pharmaceutical form:Suspension for injection-Route of administration:Intramuscular
Other Names:
  • Prevnar20™
Biological: Rotarix
Pharmaceutical form:Solution-Route of administration:Oral
Other Names:
  • Rotarix™
Biological: Priorix
Pharmaceutical form:Lyophilized, for suspension for reconstitution-Route of administration:Subcutaneous
Other Names:
  • Priorix™
Biological: VAQTA
Pharmaceutical form:Suspension for Injection-Route of administration:Intramuscular
Other Names:
  • VAQTA™
Biological: Havrix
Pharmaceutical form:Suspension for Injection-Route of administration:Intramuscular
Other Names:
  • Havrix™
Experimental: 20vPCV-20vPCV-20vPCV-PCV21
Participants will be administered via intramuscular injection (IM) a 4-dose 20vPCV regimen at approximately 2 MoA, 20vPCV at 4 MoA, 20vPCV at 6 MoA and PCV21 at 12 to 15 MoA
Biological: PCV21 vaccine
Pharmaceutical form:Suspension for injection-Route of administration:Intramuscular
Other Names:
  • 515
Biological: M-M-R II vaccine
Pharmaceutical form:Powder, lyophilized, for suspension for reconstitution-Route of administration:Subcutaneous or Intramuscular
Other Names:
  • M-M-R™ II
Biological: RotaTeq
Pharmaceutical form:Solution-Route of administration:Oral
Other Names:
  • RotaTeq™
Biological: Vaxelis vaccine
Pharmaceutical form:Suspension for injection-Route of administration:Intramuscular
Other Names:
  • Vaxelis™
Biological: Varivax
Pharmaceutical form:Powder, lyophilized, for suspension for reconstitution-Route of administration:Subcutaneous or Intramuscular
Other Names:
  • Varivax™
Biological: Prevnar 20 vaccine
Pharmaceutical form:Suspension for injection-Route of administration:Intramuscular
Other Names:
  • Prevnar20™
Biological: Rotarix
Pharmaceutical form:Solution-Route of administration:Oral
Other Names:
  • Rotarix™
Biological: Priorix
Pharmaceutical form:Lyophilized, for suspension for reconstitution-Route of administration:Subcutaneous
Other Names:
  • Priorix™
Biological: VAQTA
Pharmaceutical form:Suspension for Injection-Route of administration:Intramuscular
Other Names:
  • VAQTA™
Biological: Havrix
Pharmaceutical form:Suspension for Injection-Route of administration:Intramuscular
Other Names:
  • Havrix™
Active Comparator: 20vPCV-20vPCV-20vPCV-20vPCV
Participants will be administered via intramuscular injection (IM) a 4-dose 20vPCV regimen at approximately 2 MoA, 20vPCV at 4 MoA, 20vPCV at 6 MoA and 20vPCV at 12 to 15 MoA
Biological: M-M-R II vaccine
Pharmaceutical form:Powder, lyophilized, for suspension for reconstitution-Route of administration:Subcutaneous or Intramuscular
Other Names:
  • M-M-R™ II
Biological: RotaTeq
Pharmaceutical form:Solution-Route of administration:Oral
Other Names:
  • RotaTeq™
Biological: Vaxelis vaccine
Pharmaceutical form:Suspension for injection-Route of administration:Intramuscular
Other Names:
  • Vaxelis™
Biological: Varivax
Pharmaceutical form:Powder, lyophilized, for suspension for reconstitution-Route of administration:Subcutaneous or Intramuscular
Other Names:
  • Varivax™
Biological: Prevnar 20 vaccine
Pharmaceutical form:Suspension for injection-Route of administration:Intramuscular
Other Names:
  • Prevnar20™
Biological: Rotarix
Pharmaceutical form:Solution-Route of administration:Oral
Other Names:
  • Rotarix™
Biological: Priorix
Pharmaceutical form:Lyophilized, for suspension for reconstitution-Route of administration:Subcutaneous
Other Names:
  • Priorix™
Biological: VAQTA
Pharmaceutical form:Suspension for Injection-Route of administration:Intramuscular
Other Names:
  • VAQTA™
Biological: Havrix
Pharmaceutical form:Suspension for Injection-Route of administration:Intramuscular
Other Names:
  • Havrix™

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Presence of solicited injection site and systemic reactions through 7 days after each vaccine injection
Time Frame: Through 7 days after each vaccine injection
Number of participants experiencing solicited injection site and systemic reactions
Through 7 days after each vaccine injection
Presence of unsolicited (spontaneously reported) injection site reactions and unsolicited systemic AEs through 30 days after each vaccine injection
Time Frame: Through 30 days after each vaccine injection
Number of participants experiencing unsolicited injection site reactions and unsolicited systemic AEs
Through 30 days after each vaccine injection
Presence of any immediate adverse events (AEs)
Time Frame: Within 30 minutes after each vaccination
Number of participants experiencing solicited and unsolicited immediate AEs
Within 30 minutes after each vaccination
Presence of serious adverse events (SAEs) throughout the study (through 6 months post- last vaccine injection)
Time Frame: Throughout the study (through 6 months post-last vaccine injection), approximately 19 months
Number of participants experiencing SAEs
Throughout the study (through 6 months post-last vaccine injection), approximately 19 months
Presence adverse events of special interest (AESIs) throughout the study (through 6 months post- last vaccine injection)
Time Frame: Throughout the study (through 6 months post-last vaccine injection), approximately 19 months
Number of participants experiencing AESIs
Throughout the study (through 6 months post-last vaccine injection), approximately 19 months
Serotype Specific IgG GMCs for Each Pneumococcal Serotype at 30 Days PD4
Time Frame: 30 days PD4
The GMCs for serotype-specific pneumococcal IgG antibodies are measured using electro-chemiluminescence assay (ECL)
30 days PD4

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sanofi

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

February 27, 2025

Primary Completion (Estimated)

September 10, 2027

Study Completion (Estimated)

September 10, 2027

Study Registration Dates

First Submitted

February 7, 2025

First Submitted That Met QC Criteria

February 7, 2025

First Posted (Actual)

February 13, 2025

Study Record Updates

Last Update Posted (Actual)

February 13, 2026

Last Update Submitted That Met QC Criteria

February 12, 2026

Last Verified

February 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • PSK00031
  • U1111-1294-7911 (Registry Identifier: ICTRP)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

Qualified researchers may request access to patient level data and related study documents including the clinical study report, study protocol with any amendments, blank case report form, statistical analysis plan, and dataset specifications. Patient level data will be anonymized and study documents will be redacted to protect the privacy of trial participants. Further details on Sanofi's data sharing criteria, eligible studies, and process for requesting access can be found at: https://vivli.org

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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