(CNN) The US Food and Drug Administration expanded the emergency use authorization for Pfizer's Covid-19 vaccine on Monday to include people ages 12 to 15.
This is the first Covid-19 vaccine in the United States authorized for use in younger teens and adolescents; the vaccine had previously been authorized for people age 16 and older. Covid-19 vaccines from Moderna and Johnson & Johnson are authorized for use in people age 18 and older.
To support the extended use, the FDA reviewed data submitted by Pfizer. The company said at the end of March that a clinical trial involving 2,260 12-to-15-year-olds showed the vaccine's efficacy is 100% and it is well tolerated.
"It was a relatively straightforward decision," Dr. Peter Marks, Director of FDA's Center for Biologics Evaluation and Research, the arm of the FDA that regulates vaccines, told reporters Monday evening.
The FDA looked at the Pfizer safety and efficacy data. The agency also looked at the immune responses of some of the children who were vaccinated, and compared them to the immune responses of older teens and adults who got the shot.
"The response to the vaccine was excellent and in fact it was even better, really, in the younger age group than it was in the 16-25 age group," Marks said.
"The safety profile was very similar in 12-15-year-olds as in 16-25-year-olds."
"FDA has done everything we can to ensure that the Covid-19 vaccines we have authorized have met the agency's high standards for quality, safety and effectiveness. We know that every time an American, including members of our own families, receives a Covid-19 vaccine dose, you are putting your trust in us," FDA Acting Commissioner Dr. Janet Woodcock told the briefing.
The FDA's independent Vaccines and Related Biological Products Advisory Committee did not meet to vote on whether to recommend the expansion of the EUA to 12-to-15-year-olds.
But the US Centers for Disease Control and Prevention's Advisory Committee on Immunization Practices is scheduled to meet Wednesday to advise CDC on whether to recommend use of the vaccine in this age group. CDC Director Dr. Rochelle Walensky will then decide whether the agency will recommend the vaccine's use in the new group.
Vaccinations for 12-to-15-year-olds are not expected to begin until after that recommendation. The Biden administration has said it will quickly mobilize to ready vaccinations for 12-to-15-year-olds through the federal pharmacy program, pediatricians and family doctors.
States make the decision on who gives the vaccines, and when.
"It may be that the local pharmacy will not be able to administer because they may not be able to give a vaccine to someone younger than 16 or 17 years of age," Marks said.
"And with good reason. A 12-year-old is not the same, emotionally, as an 18-year-old. There is a difference there. So there may be differences from state to state and from location to location."
The FDA does not decide that question, Marks added. "Our authorization is for across all the United States, its territories, so it applies everywhere. It's just who will administer the vaccine may vary from jurisdiction to jurisdiction. We don't regulate the practice of medicine at FDA. We regulate these products. How they are administered may be regulated different in some states in terms of who can give a vaccine to a 12-year-old," added Marks.
State licensing boards make these decisions, said Woodcock.
"These are the state licensing boards, OK. They have the board of pharmacy, the board of medicine," Woodcock said. "And then there are different criteria under that. And local rules and regulations are what we are talking about. And then they permit the conditions of practice. So the states regulate those conditions of practice."
Expanding authorization to people 12 to 15 opens Covid-19 vaccination to another 5% of the US population, nearly 17 million more people. The expanded authorization means 85% of the US population is eligible to receive a Covid-19 vaccine.
"The light at the end of the tunnel is growing, and today it got a little brighter," President Joe Biden said in a statement.
Pfizer said last week it expects to submit for emergency use authorization for its Covid-19 vaccine for children ages 2 to 11 years old in September. Its vaccine safety and efficacy study in children ages 6 months to 11 years old is ongoing.
The FDA also scheduled a meeting of its Vaccines and Related Biological Products Advisory Committee for June 10 to discuss the potential extension of EUA to children under 12.
"During the meeting the agency will provide a status update on our approach to emergency use authorization (EUA) for COVID-19 vaccines intended for use in individuals 12 through 17 years of age," the FDA said in a statement Monday.
"The committee will also discuss the data needed to support an EUA and a biologics license application (BLA) for a COVID-19 vaccine intended for use in children less than 12 years of age. The committee will not discuss any specific products," it added. A BLA would mean full FDA approval.
Vaccines made by Moderna and by Johnson & Johnson are currently authorized for use in people 18 and older.
"We recognize that the next critical step is having vaccines available for use throughout the pediatric population," Marks said in a statement.
"As with the initial COVID-19 vaccine authorizations, we want to ensure that the public has a clear understanding of our expectations for the data and information needed to support requests for emergency use authorization and biologics license applications for vaccines intended to prevent COVID-19 in this pediatric age range."