AILSA CHANG, HOST:
The FDA now says that the COVID-19 vaccine made by Pfizer can be used for children as young as 12. This will, of course, expand the number of people in the U.S. who qualify for the vaccine. And with us now to talk about this latest development is NPR science correspondent Joe Palca.
Hey, Joe.
JOE PALCA, BYLINE: Hello, Ailsa.
CHANG: Hi. OK, so explain exactly what the FDA authorized today.
PALCA: Well, you probably remember back in December, the FDA authorized the Pfizer-BioNTech vaccine for people older than 16 years old. And even at that time, the company was starting to think about doing tests on younger children because while children don't get as sick or as frequently sick from this, there still is a risk of getting sick from COVID.
CHANG: Right.
PALCA: So they started testing it in children from 12 to 15. And they applied for this amendment to the emergency use authorization that the FDA granted them back in December. And now this application has been granted, and they can give the vaccine to younger children.
CHANG: OK. Well, tell us a little more about what the studies show about how safe and effective these vaccines are - the Pfizer vaccine, at least...
PALCA: Right.
CHANG: ...For younger people.
PALCA: Right. Well, this study was done in about 2,200 or 2,260 people - children between the ages of 12 and 15. About half got the vaccine - two doses - and half got the placebo. Very similar to adults, some people in the study had immediate side effects - a headache, tiredness, chills, muscle pain, fever and joint pain. And those that had those symptoms tended to have them more severely in the second shot, very similar to what some adults have experienced - not all of them, however. A lot of people have had the vaccine without any side effects whatsoever. So the safety profile looked good.
As far as efficacy is concerned, they - it was really remarkably good because in the trial, no one got seriously ill with COVID. The number was 100% effective in preventing COVID-19. The other thing they did, though, was they - I mean, there weren't a whole lot of cases of COVID in either group, so they have to make some inferences. And what they do is they look at the immune response - the blood, the number of antibodies that these children produced. And in looking at that, they saw a pattern that was very consistent with something that would be protective. So they were reasonably confident that this vaccine, even though they didn't have a whole lot of cases to show that it would be effective, that it probably would be effective.
CHANG: OK. Well, that's good news. Do you have any sense if any of these COVID vaccines will be approved for kids younger than 12? And what kind of timeline might that authorization be on?
PALCA: Yes, the company has already said that it's doing tests on children as young as 6 months.
CHANG: Wow.
PALCA: They're going to roll out data coming out from children, they expect, from later September, possibly, with children down to 2 year old and later in the year for children younger than that. And the other thing is that there are other companies. The other vaccine manufacturers are also looking into the safety and efficacy of their vaccines for younger people.
CHANG: That is NPR science correspondent Joe Palca.
Thank you, Joe.
PALCA: You're welcome.
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