Seamless Controlled Trial To Evaluate Safety And Immunogenicity of Chikungunya Vaccine in LatinAmerica and Asia

This study has a Phase II with part A and part B and a Phase III with part C. This Adaptive seamless design will prospectively include planned modifications and incorporate both dose selection (parts A and B) and confirmation of the selected dose (part C) based on the accumulation of subjects\' data within the entire study period as shown below. Part C will be randomized for immunogenicity subset and will be open label for safety cohort. The participants assigned to the control group from all parts (i.e, Part A, B and C) will be continuously followed up from the enrollment until the end of the study.