NCT07348692 · Sanofi
Lot-to-lot Consistency Study of a 21-valent Pneumococcal Conjugate Vaccine in Healthy Infants From 2 Months of Age
What this study is about
This is a phase 3 randomly assigned, modified where neither patients nor doctors know which treatment is given study whose purpose is to measure whether 3 lots of the experimental pneumococcal vaccine PCV21 can help the body to develop germ-fighting agents called "antibodies" (immunogenicity) in a similar way (ie, same immune response) when they are given to infants aged from approximately 2 months (42 to 89 days) and are safe compared to a licensed 20-valent pneumococcal vaccine (20vPCV) (Prevnar 20™). The study duration per participant will be up to approximately 17 months. The study vaccines (either PCV21 or 20vPCV) will be administered at approximately 2, 4, 6 and 12 months of age. group of participants A will include randomization to three PCV21 formulation groups or one 20vPCV comparator group (Group 1-4, approximately 896 total participants), whereas group of participants B will include randomization to three PCV21 formulation groups only (Groups 1-3, approximately 1299 total participants). 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, V06 separated from V05 by 30 days
View original scientific description
This is a phase 3 randomized, modified double-blind study whose purpose is to measure whether 3 lots of the investigational pneumococcal vaccine PCV21 can help the body to develop germ-fighting agents called "antibodies" (immunogenicity) in a similar way (ie, same immune response) when they are given to infants aged from approximately 2 months (42 to 89 days) and are safe compared to a licensed 20-valent pneumococcal vaccine (20vPCV) (Prevnar 20™). The study duration per participant will be up to approximately 17 months. The study vaccines (either PCV21 or 20vPCV) will be administered at approximately 2, 4, 6 and 12 months of age. Cohort A will include randomization to three PCV21 formulation groups or one 20vPCV comparator group (Group 1-4, approximately 896 total participants), whereas Cohort B will include randomization to three PCV21 formulation groups only (Groups 1-3, approximately 1299 total participants). Routine pediatric vaccines will be given as per local recommendations.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
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
Exclusion criteria
- 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
- Any contraindication to the routine pediatric vaccine being administered in the study
- History of seizure or significant stable or progressive neurologic disorders such as infantile spasms, 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 substances3
- Laboratory-confirmed or known thrombocytopenia, as reported by the parent(s) / legally acceptable representative (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 study intervention administration.
- Receipt of any BCG vaccine within 4 weeks preceding the first study intervention administration or planned receipt any BCG vaccine within the study period
- Previous vaccination against Streptococcus pneumoniae
- Previous vaccination against the following antigens: diphtheria, tetanus, pertussis, H. influenzae type b, poliovirus
- Receipt of more than 1 dose of hepatitis B vaccine
- 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.
Where
- Fayetteville, Arkansas
- Huntington Park, California
- Los Angeles, California
- Tampa, Florida
- Bardstown, Kentucky
- Allen Park, Michigan
- Charleston, South Carolina
- Simpsonville, South Carolina
- Spartanburg, South Carolina
- Edinburg, Texas
- Richmond, Texas
- Ogden, Utah
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced May 22, 2026 · Source of record for eligibility and locations