Clinical evaluation to determine the appropriate paediatric formulation of a tick-borne encephalitis vaccine

Two dose-finding studies and one open label safety study with a paediatric FSME-IMMUN® formulation were conducted in children and adolescents aged 1–15 years (N = 3697). The 1.2 μg antigen dose was identified as the optimal dose, inducing high seroconversion rates following the primary vaccination series. Adolescents (aged 12–15 years) vaccinated with the optimal paediatric dose (1.2 μg) attained similarly high seroprotective rates to adults (aged 16–35 years) vaccinated with the 2.4 μg formulation of FSME-IMMUN®. We concluded that the FSME-IMMUN® paediatric vaccine formulation is safe and highly immunogenic, not only for children <12 years, but also for adolescents <16 years.