COVID-19 Paediatric VLA2001-321 Study

This is a Randomized, Double-blinded, Active-controlled Study to evaluate the Safety, Tolerability and Immunogenicity of VLA2001 in participants of ≥2 to 12 years. The study will consist of four parts: * Dose-finding part (participants aged ≥5 to \<12 years) * Dose-finding part (participants aged ≥2 to \<5 years) * Confirmatory part (participants aged ≥5 to \<12 years) * Confirmatory part (participants aged ≥2 to \<5 years) Dose-finding part (participants aged ≥5 to \<12 years) Approximately 60 participants will receive 2 intramuscular doses of either half-dose VLA2001 (n=30) or full-dose VLA2001 (n=30) on Days 1 and 29 in a 1:1 ratio. Dose-finding part (participants aged ≥2 to \<5 years) Approximately 60 participants will receive 2 intramuscular doses of either half-dose VLA2001 (n=30) or full-dose VLA2001 (n=30) on Days 1 and 29 in a 1:1 ratio. Dose-finding part for age group ≥2 to \<5 years will be initiated after dose for age group ≥5 to \<12 years is confirmed. Confirmatory Part (participants aged ≥5 to \<12 years and ≥2 to \<5 years) Overall, approximately 1600 participants aged ≥2 to \<12 years will be enrolled. 800 participants aged ≥5 to \<12 years and 800 participants aged ≥2 to \<5 years will be randomized in 3:1 ratio. In each age group, 600 participants will receive VLA2001, and 200 participants comparator. Vaccination will start with either 1 intramuscular dose of VLA2001 (selected dose) or comparator vaccine. 28 days later all participants will receive a dose of VLA2001 (selected dose) and 28 days thereafter those who had received the comparator vaccine will receive their second dose with VLA2001 while those who have already received two doses of VLA2001 will receive the comparator vaccine.