The Food and Drug Administration said on Sunday that three doses of the Pfizer-BioNTech coronavirus vaccine appeared to be effective in preventing Covid illness in children under 5, judging by the level of virus-blocking antibodies the shots induced.
The agency’s evaluation was posted online ahead of Wednesday’s meeting of outside vaccine experts, summoned to recommend how the F.D.A. should rule on applications from both Pfizer and Moderna on vaccinating the nation’s youngest children.
Some public health experts are expecting the F.D.A. to authorize both Moderna’s and Pfizer’s vaccines, offering parents a choice between the two. The Centers for Disease Control and Prevention must also weigh in with its recommendations after the F.D.A. acts. Roughly 18 million children younger than 5 are the only Americans who are not yet eligible for shots.