A Food and Drug Administration advisory committee will meet Wednesday to weigh in on Covid vaccines for children under 5.
The committee's endorsement is a crucial step before the FDA can authorize the shots, from both Pfizer-BioNTech and Moderna, for the age group. Children under 5 are the only group in the United States who remain ineligible to get vaccinated.
Full coverage of the Covid-19 pandemic
Some parents of the roughly 18 million children in the age group have been eagerly awaiting the shots to become available. However, a recent Kaiser Family Foundation survey found that only about 1 in 5 parents with children under 5 say they intend to get their child vaccinated “right away" once federal regulators authorize it.
While children are less likely than adults to become seriously ill from Covid, some do suffer from complications — and an infected child can spread the virus to family members, giving an urgency to vaccinating this age group, health experts note.
“The sooner we can get our youngest vaccinated, the less stress families will be under after an already long two years,” said Dr. Nusheen Ameenuddin, a pediatrician at the Mayo Clinic in Rochester, Minnesota.
Vaccinations for young children could begin as early as next week, according to White House Covid coordinator Dr. Ashish Jha.
The FDA is expected to authorize the shots quickly after Wednesday's meeting of its Vaccines and Related Biological Products Advisory Committee. The Centers for Disease Control and Prevention's advisory committee is expected to meet Friday and Saturday to decide how the vaccines should be used for children under 5. If all goes as hoped, CDC Director Dr. Rochelle Walensky will sign off on the authorization, sometimes within hours of the committee's clearance.
Pfizer is asking the FDA to authorize a three-dose vaccine for children ages 6 months to 4 years, while Moderna is requesting authorization for a two-dose vaccine for kids ages 6 months to 5 years.
Over the weekend, FDA scientists released their own analysis of both vaccines, saying in briefing documents posted online that the Pfizer and the Moderna shots appear to be safe and effective in young children.
Early clinical trial results found that Pfizer's three-dose vaccine, given in 3 microgram doses, appeared to be 80 percent effective in preventing symptomatic Covid in kids, according to the FDA briefing documents.
Moderna's two-dose vaccine, given at 25 micrograms, was shown in trials to be around 40 to 50 percent effective at preventing milder infections, according to the FDA documents, though the company has said it is testing a booster dose for the age group.
Are Covid vaccines linked to myocarditis in kids?
The vaccine should protect little children against the worst outcomes of Covid. And overall, the data on the safety profile of the vaccines has so far been “very encouraging,” Ameenuddin said.
The vaccines were generally tolerated well, with pain at the injection site, irritability and sleepiness among the most common side effects reported, according to the FDA documents.
The agency noted, however, that there is currently not enough data for the age group for it to assess the risk of a rare heart inflammation condition called myocarditis.
Pfizer's and Moderna’s vaccines have been linked to rare instances of myocarditis, particularly in teen boys and young men. There were no safety concerns about heart inflammation in either of the Pfizer or the Moderna pediatric trials, which each tested the vaccines in a few thousand children.
Dr. Jesse Goodman of Georgetown University, a former FDA vaccine chief, said on a call with reporters Monday that it was "reassuring" there were no documented myocarditis cases in the clinical trials, though he noted it wouldn't be expected to be detected in such a small trial.
Should kids who have had Covid get vaccinated?
A recent CDC report found that roughly 75 percent of children 11 and under had evidence of an infection by February, up from 44 percent in December.
Dr. Paul Offit, a member of the FDA's advisory committee, said on the call Monday that studies in adults have shown that there appears to be an advantage to giving vaccinations to those who have been previously infected with the virus.
But he also questioned the efficacy of both vaccines in kids, noting that the trials took place before the omicron subvariants, BA.4 and BA.5, began rapidly spreading in the U.S.
Dr. Anna Durbin, a vaccine researcher at Johns Hopkins University in Baltimore, said that while the vaccine data looks "encouraging," young children and other groups will eventually need to get vaccinated with updated vaccines that are designed to target newer variants.
On June 28, the FDA’s advisory committee is scheduled to meet to discuss what strain or strains should be included in Covid booster shots for the fall.
Pfizer and Moderna are both working on updated shots that target the omicron variant.
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