NCT07103148 - A Phase III Control Study of the Safety and Immunogenicity of vYF in Pediatric Population | Crick

Eligibility

Sex: ALLMin age: 9 MonthsMax age: 5 YearsHealthy volunteers:

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Inclusion Criteria: * Aged 9 months to 5 years on the day of inclusion\* \* "9 months to 5 years" means from the day of the 9th month after birth to the day before the 6th year birthday * Aged 11 to 15 months\* on the day of inclusion for participants enrolled in the MMR co-administration group \* "11 to 15 months" means from the day of the 11th month after birth to the day before the 16th month birthday * Participants who are healthy as determined by medical evaluation including medical history and physical examination * For infants\*, born after a gestation period of 27 through 36 weeks and medically stable as assessed by the investigator, based on the following definition: "Medically stable" refers to the condition of premature infants who do not require significant medical support or ongoing management for debilitating disease and who have demonstrated a clinical course of sustained recovery by the time they receive the first dose of study intervention \* Infants aged 9 months to 11 months up to the day before the 12th month birthday * Participant and parent/LAR are able to attend all scheduled visits and to comply with all study procedures * ICF has been signed and dated by the parent(s) or other LAR (and by an independent witness if required by local regulations) 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 irradiation therapy, within the preceding 6 months; or long-term systemic corticosteroid therapy (prednisone or equivalent for more than 2 consecutive weeks within the past 3 months) * Known history of FV infection * Known systemic hypersensitivity to any of the study intervention components, eggs 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 * 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. * Chronic illness\* that, in the opinion of the Investigator, is at a stage where it might interfere with study conduct or completion , including malignancy, such as leukemia, or lymphoma \*Chronic illness may include, but is not limited to, cardiac disorders, renal disorders, auto-immune disorders, diabetes, psychiatric disorders or chronic infection * History of central nervous system disorder or disease, including seizures and febrile seizures * Receipt of any vaccine in the 4 weeks preceding the study intervention administration or planned receipt of any vaccine in the 4 weeks following the study intervention administration. Vaccine to be administered as part of the National Immunization Schedule will be postponed after the D29 visit * Previous vaccination against a FV disease at any time including YF with an investigational or marketed vaccine * Receipt of immune globulins, blood or blood-derived products in the past 6 months * Administration of any anti-viral within 2 months preceding the study intervention administration and up to the 6 weeks following the study intervention administration * For participants enrolled in the MMR co-administration group: previous vaccination against measles, measles/mumps/rubella * For participants enrolled in the MMR co-administration group: history of measles, mumps, rubella confirmed either clinically, serologically, or microbiologically * Known history or laboratory evidence of HIV infection * Known history of hepatitis B or hepatitis C seropositivity * Personal or family history of thymic pathology (thymoma, thymectomy, or myasthenia) * Participation at the time of study enrollment (or in the 4 weeks preceding the study intervention administration) or planned participation during the first year of the 3-year follow-up in another clinical study investigating a vaccine, drug, medical device, or medical procedure. Enrollment in another study after the first 6 months of follow-up is permitted, assuming it does not exclude participation in this study. * In an emergency setting, or hospitalized involuntary * Identified as a natural or adopted child of the Investigator or employee with direct involvement in the proposed study

Outcomes

Primary Outcomes

Percentage of participants with seroconversion to YF virus after 1 dose of vYF compared to seroconversion after 1 dose of the Stamaril in YF-naive participants (9-24 months)