This was a phase II, prospective, open-label, multicenter, outpatient study designed to evaluate the safety, tolerability, and immunogenicity of one or two doses of CAIV-T in children and adolescents between 6 and 17 years of age. Subjects were allocated to one of three study groups according to age at the time of enrollment: study group one consisted of subjects between 6 and 9 years of age, group two of subjects 10 to 12 years of age, and group three of subjects 13 to 17 years of age.
Approximately 450 subjects (ie, 150 subjects per age group) participated in the study and were scheduled to receive two intranasal doses of CAIV-T separated by 35 ± 7 days in an open-label manner.