Seventeen of the 18 members of the Vaccines and Related Biological Products Advisory Committee (VRBPAC) on Oct. 26 voted to recommend the 10-microgram shot for kids, which is one-third the dose given to adults.
One member, Michael Kurilla, MD, director of the division of clinical innovation at the National Institutes of Health, Bethesda, Md., abstained from voting.
If the FDA follows the recommendation, as it typically does, and issues an Emergency Use Authorization for the vaccine, the shots could be available within days.
After the FDA’s final decision, the Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices will meet to make specific recommendations for its use. The CDC committee must stick closely to the conditions for use spelled out in the EUA, so their recommendations are likely to be similar to those made by the FDA. Their next meeting is scheduled for Nov. 2 and 3.
In the end, some on the panel felt uneasy with their decision.
“I voted yes primarily because I wanted to make sure that children who really need this vaccine, the Black and brown children of our country, get the vaccine,” said James Hildreth, MD, PhD, president and CEO of Meharry Medical College in Nashville.
“But to be honest, the best way to protect the health of some children will be to do nothing because they will be just fine,” he said.
Others said they were surprised by how difficult the decision had been.
“This is a much tougher one than we had expected going into it,” said committee member Eric Rubin, MD, editor and chief of the New England Journal of Medicine, during the FDA advisory committee’s meeting.
Ahead of the vote, the committee heard presentations outlining the expected benefits of vaccinating children along with potential risks.
“Children have been greatly impacted by the pandemic,” said Fiona Havers, MD, a medical officer with the CDC in Atlanta who reviewed the epidemiology of COVID-19 in kids.
In the second year of the pandemic, as more seniors have been vaccinated against the virus, COVID cases have largely shifted from older to younger age groups.
So far, there have been more than 1.9 million COVID-19 cases in children ages 5 through 11 in the United States.. Cases in kids saw a big jump in July and August with summer travel, schools reopening, and the dominance of the Delta variant.
And those are just the cases reported to the CDC. Regular testing of anonymous blood samples collected at sites across the United States indicates that 6 times as many kids have had COVID than what is reflected in official counts.
Last winter, blood sample testing showed about 13% of children had antibodies against the virus, suggesting they’d been infected. By this summer, that number had risen to 42%.
That figure clearly made an impression on many members of the committee who asked the FDA’s vaccine reviewers if they had tried to account for immunity from past infections in their modeling. They had not.
Some felt that even with a highly effective vaccine — new data presented by Pfizer showed the children’s dose was 90% effective at preventing symptomatic infections in kids — caution was warranted as much is still unknown about myocarditis, a rare side effect of the mRNA vaccines.
Myocarditis has been more common in younger age groups. It usually goes away over time but requires hospital care. It’s not known if myocarditis could have lingering effects for those who experience it.
There were no cases of myocarditis seen in Pfizer’s studies of the vaccine in children, and no other serious events were seen. Vaccine side effects reported in the Pfizer studies were mostly mild and included fatigue, headache, and pain at the injection site.
“We think we have optimized the immune response and minimized our reactions,” said William Gruber, MD, senior vice president vaccine research and clinical development at Pfizer.
But the studies didn’t include enough participants to pick up rare, but serious adverse events like myocarditis.
“We’re worried about a side effect that we can’t measure yet, but it’s probably real, and we see a benefit that isn’t the same as it is in older age groups,” said Dr. Rubin.