Skip to content

Study of the Safety and Immunogenicity of Catch-up Vaccination With a 21-valent Pneumococcal Conjugate Vaccine (PCV21) in Healthy Infants, Toddlers, Children, and Adolescents

A Phase 3, Randomized, Modified Double-blind, Active-controlled, Parallel-group Study to Investigate the Safety and Immunogenicity of Catch-up Vaccination Regimens of a 21-valent Pneumococcal Conjugate Vaccine in Healthy Infants, Toddlers, Children, and Adolescents

Status
Active, not recruiting
Phases
Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT06838000
Enrollment
1268
Registered
2025-02-20
Start date
2025-02-28
Completion date
2026-12-01
Last updated
2025-10-06

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Pneumococcal Infections

Keywords

Pneumococcal Vaccines, Pneumococcal Conjugate Vaccine, Healthy Participants

Brief summary

The purpose of this study is to evaluate the safety and immunogenicity of PCV21 versus 20vPCV ( 20-valent pneumococcal conjugate vaccine, Prevnar 20) for catch-up vaccination in infants (7 to 11 MoA-Months of age), toddlers (12 to 23 MoA), and children/adolescents (2 to 5 YoA and 6 to 17 YoA-years of age).

Detailed description

The duration of each participation will be approximately 9 to 11 months for each infant participant, 8 to 9 months for each toddler participant, and 6 months for each child/adolescent participant.

Interventions

BIOLOGICALPCV21

Investigational pneumococcal conjugate vaccine

BIOLOGICAL20vPCV

20-valent pneumococcal conjugate vaccine

Sponsors

Sanofi Pasteur, a Sanofi Company
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
SINGLE (Subject)

Masking description

Modified double-blind: * Blinding for vaccine group assignment: participants and participant's parent(s) / legally acceptable representative(s) (LARs), outcome assessors, Investigators, laboratory personnel, and Sponsor study staff * No blinding for vaccine group assignment: those preparing and administering the study interventions

Intervention model description

Control-Method: Active Controlled

Eligibility

Sex/Gender
ALL
Age
7 Months to 17 Years
Healthy volunteers
Yes

Inclusion criteria

AGE * Aged 7 months to 17 years on the day of inclusion TYPE OF PARTICIPANT AND DISEASE CHARACTERISTICS * Participants who are healthy as determined by medical evaluation including medical history and physical examination For infants (7 to 11 MoA) and toddlers (12 to 23 MoA) only * 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 SEX, CONTRACEPTIVE/BARRIER METHOD AND PREGNANCY TESTING REQUIREMENTS For adolescents (6 to 17 YoA) only * A female participant is eligible to participate if she is not pregnant or breastfeeding and one of the following conditions applies: * Is of non-childbearing potential. To be considered of non-childbearing potential, a female must be pre-menarche or surgically sterile. OR * Is of childbearing potential and agrees to use an effective contraceptive method or abstinence from at least 4 weeks prior to the study vaccine administration until at least 4 weeks after the study vaccine administration. A female participant of childbearing potential must have a negative highly sensitive pregnancy test (urine or serum as required by local regulation) within 25 hours of before the first dose of study vaccine. INFORMED CONSENT * Assent form has been signed and dated by the participant (based on local regulations), and if applicable, and informed consent form has been signed and dated by the parent(s) or another legally acceptable representative (LAR) and by an independent witness, if required by local regulations OTHER INCLUSIONS * Participant and parent(s) / LAR(s) are able to attend all scheduled visits and to comply with all study procedures

Exclusion criteria

MEDICAL CONDITIONS * Known or suspected congenital or acquired immunodeficiency; or receipt of immunosuppressive therapy, such as anti-cancer chemotherapy or radiation therapy, within the preceding 6 months; or long-term systemic corticosteroid therapy * History of microbiologically confirmed S. pneumoniae infection or disease * History of seizure or significant stable or progressive neurological disorders such as inflammatory nervous system diseases, encephalopathy, and cerebral palsy * Known systemic hypersensitivity to any of the vaccine components, or history of a life-threatening reaction to the vaccines used in the study or to a product containing any of the same substances * Laboratory-confirmed thrombocytopenia, or known thrombocytopenia, as reported by the parent(s) / LAR(s), 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 vaccine administration. For infants (7 to 11 MoA) and toddlers (12 to 23 MoA) only * Previous vaccination against S. pneumonia For children (2 to 5 YoA) and adolescents (6 to 17 YoA) only * Previous vaccination with pneumococcal polysaccharide vaccine For adolescents (6 to 17 YoA) only * Alcohol, prescription drug, or substance abuse that, in the opinion of the Investigator, might interfere with the study conduct or completion PRIOR/CONCOMITANT THERAPY * Receipt of any vaccine in the 4 weeks preceding the vaccine administration or planned receipt of any vaccine in the 4 weeks following the vaccine administration, except for US licensed influenza vaccination, which may be received at least 2 weeks before or 2 weeks after any study vaccination. This exception includes monovalent pandemic influenza vaccines and multivalent influenza vaccines, as applicable per local recommendations * Receipt of immune globulins, blood or blood-derived products in the past 3 months For children (2 to 5 YoA) and adolescents (6 to 17 YoA) only * Receipt of oral or injectable antibiotic therapy within 72 hours prior to the first blood draw PRIOR/CONCURRENT CLINICAL STUDY EXPERIENCE * Participation at the time of study enrollment (or in the 6 weeks preceding the first vaccine administration) or planned participation during the present study period in another clinical study investigating a vaccine, drug, medical device, or medical procedure OTHER EXCLUSIONS For adolescents (6 to 17 YoA) only * Deprived of freedom by an administrative or court order, or in an emergency setting, or hospitalized involuntarily * Identified as an Investigator or employee of the Investigator or study center with direct involvement in the proposed study, or identified as an immediate family member (ie, parent, spouse, natural or adopted child) of the Investigator or employee with direct involvement in the proposed study The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial

Design outcomes

Primary

MeasureTime frameDescription
Number of Children/adolescents (6-17 YoA):with serotype specific OPA titers for all serotypes included in PCV21On day 30Serotype specific OPA titers for each pneumococcal serotype are determined.
Number of participants reporting solicited injection site and solicited systemic reactionsUp to Day 7 post-vaccination
Number of participants reporting unsolicited (spontaneously reported) injection site reactions and unsolicited systemic AEs after each and any injection of a pneumococcal vaccineWithin 30 days after vaccination
Number of participants reporting serious adverse events (SAEs) and adverse events of special interest (AESIs)From day 0 to day 517SAEs and AESIs are collected throughout the study period
Number of Infants (7-11 months of age [MoA]) and toddlers (12-23 MoA): with serotype-specific IgG concentrations for all serotypes included in PCV21On day 30 after last vaccinationAb (antibody) concentrations for each pneumococcal serotype are measured.
Number of Children (2-5 years of age [YoA]):with serotype specific OPA titers for all serotypes included in PCV21On day 30Serotype specific OPA titers for each pneumococcal serotype are determined.
Number of Children (2-5 years of age [YoA]):with serotype specific IgG concentrations for all serotypes included in PCV21On day 30Ab concentrations for each pneumococcal serotype are measured.
Number of participants reporting immediate adverse events (AEs)Within 30 minutes post-vaccinationUnsolicited (spontaneously reported) systemic AEs after each and any injection of a pneumococcal vaccine

Secondary

MeasureTime frameDescription
Number of Children/adolescents (≥ 2 YoA): with serotype specific IgG concentrations for all serotypes included in PCV21On day 30Ab concentrations for each pneumococcal serotype are measured.
Number of participants (all age groups) with serotype specific IgG concentration ≥ 0.35 μg/mL for all serotypes included in PCV21On day 30 after last vaccinationAb concentrations for each pneumococcal serotype are measured.
Number of infants (7-11 MoA) and toddlers(12-23 MoA):with serotype specific OPA titers for all serotypes included in PCV21On day 30 after last vaccinationSerotype specific OPA titers for each pneumococcal serotype are determined.
Percentage of infants (7-11 MoA) and toddlers(12-23 MoA): with serotype specific OPA titers ≥ LLOQ for all serotypes included in PCV21On day 30 after last vaccinationSerotype specific OPA titers for each pneumococcal serotype included in the PCV21 formulations are determined. The following threshold values will be considered: ≥ lower limit of quantitation (LLOQ)
Number of Children/adolescents (6-17 YoA):with serotype specific IgG concentrations for all serotypes included in PCV21On day 30Ab concentrations for each pneumococcal serotype are measured.
Number of Children/adolescents (≥ 2 YoA) with serotype specific OPA titers for all serotypes included in PCV 21On day 30Serotype specific OPA titers for each pneumococcal serotype are determined.

Countries

Estonia, Poland, Thailand, United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026