Pfizer, Moderna to expand COVID-19 vaccine trials for children ages 5 to 11

SAN FRANCISCO (KGO) -- With the start of in-person school weeks away, Pfizer and Moderna will expand the size of their COVID-19 vaccine studies in children ages 5 to 11.

According to a report, the decision came after a push from the FDA, which UCSF infectious disease doctor, Monica Gandhi, says was a smart move by the federal agency.

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"We don't want parents to not feel safe to give it to their kids," she said. "Parents are going to want to know that they did their due diligence and studied it in enough children to ensure that a rare side effect is detected."

The rare side effect myocarditis, or heart inflammation, has been reported in a small number of teenagers, mostly boys, who got the Pfizer or Moderna shots.

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"Sometimes the hospitalizations were just precautionary, because we were learning more about this," said Dr. Alan Schroeder, a critical care pediatrician at Stanford, who treated a handful of patients with myocarditis. "All of them did quite well."

The trials, now expanding by several thousand children, will be more likely to pick up on any negative reactions. "We really don't want to cause harm to healthy children through the vaccine," said Dr. Schroeder, who also says how psychologically important increased safety data is for parents.

"You feel like you have some control over whether your kid gets COVID or not. Whereas you don't feel like you have any control over whether they have a side effect of the vaccine," he continued. "That loss of a sense of control is difficult for parents and why I think many parents want to be reassured by safety data."

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Both Dr. Schroeder and Dr. Gandhi have 13 year old sons who are fully vaccinated and doing well.

Smaller dosing regimens are being tested in young children to further ensure safety.

"I think with the combination of the smaller doses and bigger sample size, they're really stressing safety," said Dr. Gandhi, who also says even if vaccines don't get authorized for children under 12 by September, in-person learning should take place. "Because we have ways to keep teachers and children safe."

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