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Vaccine regulators are weighing wider eligibility rules as the omicron and delta variants sicken more Americans, prompting many to seek out a third dose. Under a newly amended emergency use authorization for Pfizer and BioNTech's vaccine, which has so far been administered 276 million times in the United States, 16- and 17-year-olds can now get booster shots.
The U.S. Food and Drug Administration said Thursday that the vaccine's effectiveness in protecting adults against COVID-19 supported its decision to offer younger people a third dose. Now, anyone in the United States age 16 or older with at least six months' distance from a second shot is eligible for a booster.
"The Pfizer-BioNTech COVID-19 vaccine has been available to individuals 16 years of age and older for nearly a year, and its benefits have been shown to clearly outweigh potential risks," Peter Marks, FDA director for biologics evaluation and research, said in a statement. "Since we first authorized the vaccine, new evidence indicates that vaccine effectiveness against COVID-19 is waning after the second dose of the vaccine for all adults and for those in the 16- and 17-year-old age group."
Findings published in October in The Lancet, a peer-reviewed medical journal, suggest the Pfizer-BioNTech vaccine is only 47% effective at preventing COVID-19 five to six months after its second dose.
The FDA's announcement came a day after Pfizer and BioNTech said their vaccine was most effective against the omicron variant after a third dose. Blood tests on individuals who had received only two shots turned up fewer protective antibodies than did patients with three shots.
"Although two doses of the vaccine may still offer protection against severe disease caused by the omicron strain, it's clear from these preliminary data that protection is improved with a third dose of our vaccine," Albert Bourla, Pfizer's chief executive, said in a statement.
In another release following Thursday's new emergency authorization for 16- and 17-year-olds, Bourla called the FDA's decision a "critical milestone" in fighting the coronavirus. The companies plan to send the department data from phase 3 trials showing vaccinated patients in this age group and older were 95% less likely to catch COVID-19 after the third dose.
The Centers for Disease Control and Prevention on Thursday also recommended this age group get the Pfizer-BioNTech booster, according to The Associated Press.