The data from studies in children ages 5-11 showed that this dosage is safe and effective. This is reinforced by the strong safety profile of the Pfizer vaccine in adolescents, teenagers, and adults, with more than 400 million doses given.  Children ages 5-11 made similar antibody responses as adults do. The children participating in the Pfizer study will continue in the study for a total of two years so that their safety can continue to be monitored, and updates will be shared as they become available.