Moderna says COVID-19 vaccine generates 'robust' response in kids 6-11

Pfizer COVID-19 vaccine highly effective in kids 5-11, company says

Pfizer says its COVID-19 vaccine is safe and nearly 91% effective at preventing symptomatic infections in kids 5-11, based on clinical trial data released Oct. 22, 2021.

CAMBRIDGE, Mass. - Moderna’s COVID-19 vaccine generated a "robust" neutralizing antibody response in children ages 6 to 11, the company said Monday in a statement.

Moderna said it plans to seek authorization from the U.S. Food and Drug Administration for the age group soon.

The company shared interim data from its Phase 2/3 study, which showed that two smaller doses of its COVID-19 vaccine given 28 days apart were generally well-tolerated in more than 4,750 children. The participants in the trial were given 50 micrograms of vaccine, which is just half the dose given to adults.

One month after the second dose, participants in Moderna’s trial had antibody levels that were 1.5 times higher than those observed in young adults, the company said.

Moderna said the majority of the side effects in the trial, which had a total of 4,753 participants, were mild or moderate. The most common side effects were fatigue, headache, fever and pain at the injection site.

"We are encouraged by the immunogenicity and safety profile of mRNA-1273 in children aged 6 to under 12 years and are pleased that the study met its primary immunogenicity endpoints," Moderna CEO Stéphane Bancel said in the statement.

Dr. Salma Elfaki holds a vial of Moderna COVID-19 vaccine at

FILE - A vial of Moderna’s COVID-19 vaccine is shown at a Moderna clinical trial for adolescents in Orlando, Florida, on Sept. 25, 2021. (Photo by Paul Hennessy/SOPA Images/LightRocket via Getty Images)

The company said it plans to submit the data to the FDA, European Medicines Agency and other global regulators "soon."

Moderna’s results were shared a day before an influential advisory panel to the FDA is scheduled to review and discuss data from Pfizer-BioNTech’s COVID-19 vaccine for children ages 5 to 11.

Last week, Pfizer shared study results showing that kid-size doses of its vaccine appear safe and nearly 91% effective at preventing symptomatic infections in 5- to 11-year-olds.

Full-strength Pfizer shots already are authorized for anyone 12 or older, but pediatricians and many parents are anxiously awaiting protection for younger children to stem rising infections from the extra-contagious delta variant and help keep kids in school. Moderna’s COVID-19 vaccine is currently only approved for those 18 and older.

If U.S. regulators give the go-ahead, Pfizer’s shots could begin in early November — with the first children in line fully protected by Christmas.

The Biden administration said last week that it has purchased enough kid-size doses for the nation’s roughly 28 million 5- to 11-year-olds. Those doses are distributed in special orange-capped vials to distinguish them from the adult vaccine.

While children run a lower risk of severe illness or death than older people, COVID-19 has killed more than 630 Americans 18 and under, according to the CDC. Nearly 6.2 million children have been infected with the coronavirus, more than 1.1 million in the last six weeks as the delta mutant surged, the American Academy of Pediatrics says.

Both Pfizer and Moderna are studying even younger children as well, down to 6-month-olds. Results are expected later in the year.

This story was reported from Cincinnati.

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