In a briefing document posted to the FDA website late Friday, agency scientists said that they had used the data to model benefits and risks to kids ages 5-11 over a range of scenarios.
No cases of heart inflammation called myocarditis or pericarditis were detected among the children enrolled in the initial clinical trials of the vaccine, which is one-third the dose given to adults and teens.
But this side effect is one researchers are especially keeping an eye on for kids because younger people seem to be experiencing it more often than middle-aged adults and seniors.
So to be cautious, government statisticians assumed in their modeling that if the shots were given to millions of kids, there might be the same number of those rare cases in younger children as there have been in youth ages 12 to 15.
Though the benefits of these shots for kids are “highly dependent” on COVID-19 transmission in the community, the number of “clinically significant” COVID-19 harms prevented would “clearly outweigh” the numbers of vaccine-associated myocarditis cases over a range of levels of COVID infections in the community.
There was one caveat, however. When levels of COVID-19 infections are low — around the levels seen in June of this year -- the number of kids hospitalized for myocarditis could outweigh the number hospitalized for COVID-19.
But the FDA analysts noted that kids who are hospitalized for COVID-19 tend to be much sicker than those admitted for myocarditis, meaning the inoculations were still worth it, because they might prevent other harms, like a serious, delayed reaction to the virus called MIS-C and long-haul COVID-19.
“The overall benefits of the vaccine may still outweigh the risks under this low incidence scenario,” they wrote.
The scientific review is part of a package of materials prepared for a group of experts who will meet Tuesday to advise the FDA on its authorization of the vaccine for children.