In a highly anticipated announcement, Pfizer said on Monday a Phase 2/3 trial showed its Covid-19 vaccine was safe and generated a "robust" antibody response in children ages 5 to 11. These are the first such results released for this age group for a US Covid-19 vaccine, and the data has not yet been peer-reviewed or published. Pfizer said it plans to submit to the FDA for emergency use authorization soon. The trial included 2,268 participants ages 5 to 11 and used a two-dose regimen of the vaccine administered 21 days apart. This trials used a 10-microgram dose -- smaller than the 30-microgram dose that has been used for those 12 and older.