This is a new step towards the vaccination of children across the Atlantic.
The US Medicines Agency (FDA) has said that Pfizer's Covid vaccine is safe and effective in children under five, ahead of a meeting to decide on its authorization this week.
Children under five are the only group not yet eligible for the Covid vaccination in the United States and most countries.
However, their rate of hospitalization and death is "higher than in children and adolescents aged 5 to 17", indicates the FDA in a document published on its site on Sunday.
Low dose injections
The agency is organizing a meeting of experts on June 15 to decide whether or not to recommend the Pfizer vaccine (given in three injections to children aged six months to five years) as well as that of Moderna (two injections for children aged six months to five years).
The first two injections of Pfizer are given three weeks apart, and the third is given eight weeks after the second.
They are all dosed at three micrograms, compared to 30 micrograms for people 12 and older and 10 micrograms for ages five and older.
Pfizer and Moderna had previously released their findings in press releases, but the FDA had to review the data and conduct its own assessment.
She released a favorable analysis for Moderna on Friday.
6% of population
His comments about Pfizer also sound favorable, based on infection-blocking antibody levels in trial participants and a similar side effect profile in older age groups.
About 4,500 children participated in the trial.
A preliminary estimate put the vaccine's effectiveness at 80.3%, but the FDA noted that figure was based on very few positive cases - just 10, compared to the 21 sought for a more precise estimate.
There are nearly 20 million American children under the age of five, or 6% of the population.
If, as expected, FDA-appointed experts recommend both vaccines, the matter will go to another panel convened by the Centers for Disease Prevention and Control (CDC), which will have the final say.
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