Pfizer and BioNTech submit data they say shows shots are safe in 5- to 11-year-olds.

Pfizer and BioNTech announced on Tuesday that they had submitted data to the Food and Drug Administration showing that their coronavirus vaccine is safe and effective in children ages 5 to 11.

The companies said that they would submit a formal request to regulators to allow a pediatric dose of their vaccine to be administered in the United States in the coming weeks. Similar requests will be filed with European regulators and in other countries.

Pfizer and BioNTech announced favorable results from their clinical trial with more than 2,200 participants in that age group just over a week ago. The F.D.A. has said that it will analyze the data as soon as possible.

The companies said last week that their vaccine had been shown to be safe and effective in low doses in children ages 5 to 11, offering hope to parents in the United States who are worried that a return to in-person schooling has put youngsters at risk of infection.

About 28 million children ages 5 to 11 would be eligible for the vaccine in the United States, far more than the 17 million of ages 12 to 15 who became eligible for the vaccine in May.

But it is not clear how many in the younger cohort will be vaccinated. Inoculations among older children have lagged: Only about 42 percent of children ages 12 to 15 have been fully vaccinated in the United States, compared with 66 percent of adults, according to federal data.

Although many remain eager to inoculate their children, opinion polls suggest that some parents have reservations. A survey published last month by the Kaiser Family Foundation found that 26 percent of parents of children ages 5 to 11 would vaccinate their children “right away” once doses were authorized for their age group, 40 percent said they would “wait and see” how the vaccine worked before doing so and 25 percent said they would not have their child vaccinated at all.

Studies have shown that unvaccinated children who contract the coronavirus tend not to get seriously ill, leading some parents to wonder whether the potential risks of a new vaccine outweigh the benefits.

And some parents who are themselves vaccinated have expressed concerns about the relatively small size of children’s trials and about a lack of data on the long-term safety of the shots.