The agency announced authorization on Tuesday after the companies submitted the application in late April following a study that showed children under 12 had a "strong immune response" from a third dose of their COVID vaccine.
A booster shot after at least five months is believed to raise Omicron-fighting antibodies by 36 times.
"While it has largely been the case that COVID-19 tends to be less severe in children than adults, the omicron wave has seen more kids getting sick with the disease and being hospitalized, and children may also experience longer term effects, even following initially mild disease," Dr. Robert Califf, FDA Commissioner, said in a release. "The FDA is authorizing the use of a single booster dose of the Pfizer-BioNTech COVID-19 Vaccine for children 5 through 11 years of age to provide continued protection against COVID-19."
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JOEL SAGET/AFP via Getty Images Pfizer COVID-19 vaccine
Pfizer and BioNTech's first two doses of the COVID-19 vaccine received emergency approval from the U.S. Food and Drug Administration for children ages 5 to 11 years old in November 2021.
More than 8 million children in the age group in the U.S. have already received the first two doses of the vaccine.
"The Pfizer-BioNTech COVID-19 Vaccine is effective in helping to prevent the most severe consequences of COVID-19 in individuals 5 years of age and older," said Dr. Peter Marks, director of the FDA's Center for Biologics Evaluation and Research. "The FDA has determined that the known and potential benefits of a single booster dose of the Pfizer-BioNTech COVID-19 Vaccine for children 5 through 11 years of age at least five months after completing a primary series outweigh its known and potential risks and that a booster dose can help provide continued protection against COVID-19 in this and older age groups."
The Pfizer vaccine is the only COVID vaccine authorized for use in the U.S. for children ages 5 to 11.
And since last November when Pfizer's COVID-19 vaccine was approved for use in 5 to 11 year olds, the majority of hospitalizations — 9 in 10 — were in kids who were unvaccinated, the CDC reported.