The drug being tested in this study is called TAK-850, that is under development as a vaccine for influenza infection. This study will evaluate the safety and immunogenicity of TAK-850 in healthy Japanese children when given as an intramuscular injection.~The study will enroll approximately 99 participants (33 per treatment group) to receive TAK-850 in open label fashion, The participants will be assigned to each treatment group as follows:~a single intramuscular injection of TAK-850/0.5 mL in 13 to 19 years old healthy Japanese children,~Two injections of TAK-850/0.5 mL in 3 to 12 years old healthy Japanese children,~Two injections of TAK-850/0.25 mL in 6 to 35 months old healthy Japanese children.~The overall time to participate in this trial is 22 days (13-19 years old) or 43 days (6 months to 12 years old). Participants will make up to 2 visits (13-19 years old) or 3 visits (6 months to 12 years old) to the site.
The purpose of this study is to evaluate the safety and immunogenicity of an intramuscular injection of TAK-850 in healthy pediatric Japanese participants.