All 22 members of the FDA’s Vaccines and Related Biological Products Advisory Committee voted “yes” in response to two questions of whether the benefits of the vaccine — when given as two 100-microgram doses for ages 12 to 17 and two 50-microgram doses for ages 6 to 11 — outweigh its risks, based on the available scientific evidence.
“The questions are whether the data support us voting for an emergency use authorization, and I would say that that is probably true,” committee member Dr. Archana Chatterjee, dean of the Chicago Medical School at Rosalind Franklin University, said in Tuesday’s meeting.
“I am supportive of these two voting questions,” said member Dr. Hank Bernstein, a professor of pediatrics at the Zucker School of Medicine at Hofstra/Northwell.
“A third dose will likely be indicated due to evolving variants that are going to continue since so many people are continue to be unvaccinated, even with the primary series,” he said. “I think adding this vaccine, making it more available to families, is good. Families like more choice.”
The FDA, which typically follows the committee’s decisions, will now decide whether to authorize the vaccine for emergency use in these age groups. The Moderna vaccine is already authorized for adults.
However, shots can’t be given until the US Centers for Disease Control and Prevention’s own vaccine advisers have voted on whether to recommend them and CDC Director Dr. Rochelle Walensky has signed off on the recommendation.
Questions emerge around a third dose
The committee members voted on the benefits of Moderna’s vaccine as a two-dose primary series for children and teens, but discussions could continue on if or when booster doses might be needed for younger ages.
“I’m comfortable saying that I think the benefits clearly outweigh the risks, but I say that with the comfort being provided that there will be a third dose,” member Dr. Paul Offit, director of the Vaccine Education Center at Children’s Hospital of Pennsylvania, said in Tuesday’s meeting.
Pfizer/BioNTech’s Covid-19 vaccine is already authorized for use as a booster dose in children as young as 5.
Offit said three doses of vaccine are needed to help protect against coronavirus variants, such as Omicron’s BA.1 and BA.2 subvariants.
“I disagree with the term ‘booster dose.’ The third dose is not a booster dose for the Omicron subvariants,” Offit said. “This is a three-dose primary series.”
Language about the future need for additional doses could be included in the emergency use authorization for the vaccine, Chatterjee said.
Yet “the importance of additional doses as the pandemic progresses cannot be minimized,” she added.
“It’s something for our FDA colleagues to maybe take note of,” she said. “They can certainly put language in the authorization document to suggest that additional doses might be needed in these children that will be receiving only two doses to start with.”
Moderna’s vaccine has been estimated to be 93.3% effective against symptomatic Covid-19 among adolescents ages 12 to 17 when the original coronavirus and the Alpha variant were dominant.
The vaccine was estimated to be 76.8% effective against symptomatic Covid-19 for children ages 6 to 11 when the Delta variant was dominant. However, the FDA also noted that for children in that age group, the “vaccine efficacy could not be reliably determined due to the small number of COVID-19 cases accrued during the study.”
The vaccine was also found to be safe in all age groups, with adverse reactions described as “mostly mild to moderate in severity, generally of short duration,” and happening more frequently after the second dose than the first, according to the FDA briefing document.
Injection site pain was the most commonly reported adverse reaction. As for serious adverse events, the document described them as infrequent and didn’t raise any concerns. No deaths were reported.
Although there were no known cases of myocarditis or pericarditis associated with the vaccine, they are acknowledged as one of the known risks and have been reported mostly in males ages 18 to 24.
Up next: Vaccines for younger kids
They will also discuss amending the authorization of the Pfizer/BioNTech vaccine to include ages 6 months through 4 years.
The safety of Covid-19 vaccines for younger children will be an important part of those discussions, an FDA official said Tuesday.
“These vaccines will essentially extend down to the younger age ranges of as low as 6 months,” Dr. Peter Marks, director of the Center for Biologics Evaluation and Research, told the committee. “Obviously, the safety in this population is of paramount importance, and I think there’ll be a fair amount of discussion by the committee on this particular area.”
The White House has said vaccines for the youngest children could start next week if the FDA and CDC authorize them.