The Food and Drug Administration on Monday cleared the Pfizer-BioNTech Covid-19 booster dose for children ages 12 to 15.
The omicron variant is spreading rapidly among younger people in the U.S. According to NBC News data, the country set a record Sunday for total pediatric patients hospitalized with confirmed and suspected Covid, pointing to the need for young teens to be vaccinated.
The FDA also shortened the timing of Pfizer's booster shots from six months to five months after the initial series of shots, based on Israeli research, for everyone over age 12.
The Center for Disease Control and Prevention’s panel of advisors is scheduled to meet Wednesday to determine whether the booster shots should be recommended for kids ages 12 to 15.
On Tuesday, the CDC recommended that 5-11 year olds who are immune compromised, such as those who have had organ transplants, receive an extra dose of Pfizer vaccine 28 days after their second shot, following the FDA's action. Only the Pfizer Covid vaccine is authorized for 5-11 year olds.
The change in booster recommendation to five months after the initial vaccine series means tens of millions more Americans will now be eligible for an extra dose. Currently, only about 33 percent of eligible people in the U.S. have received a Covid vaccine booster, according to the CDC, even though two doses of the Pfizer vaccine have diminished effectiveness against the omicron variant. On Tuesday, the CDC officially shortened the waiting period for an extra Pfizer dose to five months for people 16 and older.
The decreased time period to wait for a booster only applies to those who had the Pfizer shots. Those who received the Moderna shots should still wait six months before getting the booster, the FDA said, citing a lack of data from Moderna to change the recommended time period.
Advice for those who got the one-dose Johnson & Johnson shot is not as clear.
Boosters for Johnson & Johnson are given after two months. But for those people who have already received a booster dose of an mRNA vaccine following their original Johnson & Johnson shot are not eligible at this point for a third dose.
The director of the FDA's Center for Biologics Evaluation and Research, Dr. Peter Marks, predicted it will take "weeks to months" for the agency to sort through data on mixing the Johnson & Johnson vaccine with third doses of one of the mRNA vaccines.
"Those data are becoming available from those who receive complex combinations in Europe and elsewhere," Marks said. "As we get those data, we'll analyze them and then potentially make recommendations."
The change in timing for Pfizer's booster comes from studies of more than 6,300 teens ages 12 to 15 in Israel. That research suggested that a Pfizer booster dose may protect them from the omicron variant better when given at five months, rather than six.
"With the current wave of the omicron variant, it's critical that we continue to take effective, life-saving preventative measures such as primary vaccination and boosters, mask wearing and social distancing in order to effectively fight Covid-19," acting FDA Commissioner Dr. Janet Woodcock said in a statement.
The agency said that it found "no new safety concerns" following a booster shot in young teenagers, and that there were no new reports of two types of heart inflammation called myocarditis or pericarditis linked to the boosters.
The Pfizer booster shot is the exact same dosage as the first two shots.