Phase III Study Comparing Safety and Immune Response of vYF Vaccine to Licensed Yellow Fever Vaccines in Children Aged 9 Months to 5 Years, Including Co-administration with MMR Vaccine

What this Trial Is About

Researchers are evaluating an investigational vaccine called vYF to determine if it is safe and helps the body develop antibodies against yellow fever compared to two licensed vaccines, Stamaril and YF-VAX. The study also looks at how vYF works when given together with the measles, mumps, and rubella MMR vaccine in infants aged 11 to 15 months. This Phase III trial aims to provide important information about the immune response and safety of these vaccines in young children. Eligible children from 9 months to 5 years old will be randomly assigned to receive one dose of either vYF, Stamaril, or YF-VAX vaccine. A special group of infants aged 11 to 15 months will receive vYF together with the MMR vaccine during the same visit. About three years after the first dose, a smaller group of participants aged 9 to 24 months will be invited to receive a booster dose of the vaccine they initially received, followed by an additional 6 months of observation for these participants. Participants will be involved for about three years, during which their immune response will be measured at several time points, including before vaccination, days 11, 15, 29, 6 months, and yearly up to 3 years. Safety will be closely monitored through reports of side effects and medical assessments after each vaccination. Blood samples and other tests will be used to track antibody levels and vaccine effects, helping researchers understand how well the vaccines work and their safety profiles over time.

A Phase III Control Study of the Safety and Immunogenicity of vYF in Pediatric Population