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Children enroll in Pfizer and Moderna trials for those under 12 - The Washington Post 

”Investigators are scaling the dosing according to age. In the Moderna trial, some children 6 to 11 years old are starting at adult doses or given less; younger children are starting with lower doses. Pfizer is starting children with a third of a dose and scaling up, and then basing younger children’s doses on older children’s responses. The Pfizer vaccine approved last week for 12-to-15-year-olds is the same dose as for adults, but sometimes lower doses are equally effective in children because their immune systems may be more responsive.“