In its study, Moderna determined that children aged 6 to 11 years old, who were vaccinated with two 50 microgram doses, had 1.5 times higher antibody levels than those observed among vaccinated young adults.
The dosage used for the children is half of the 100 micrograms used for the initial two adult shots, but the same amount authorized for the booster shot.
With the vaccine, these children showed a “robust neutralizing antibody response” and a “favorable safety profile” consistent with adolescent and adult response, the company noted.
Most adverse events were considered mild or moderate, with the most prevalent symptoms being fatigue, headache, fever and injection site pain.
The ongoing trial included more than 4,700 participants between the ages of 6 and 11 who will be monitored for a year after their second shot.
The company said it plans to submit data to the Food and Drug Administration (FDA) and other regulators, including in Europe, “in the near term.”
Moderna CEO Stéphane Bancel said the company is “encouraged” by the results showing effectiveness and safety.
“We look forward to filing with regulators globally and remain committed to doing our part to help end the COVID-19 pandemic with a vaccine for adults and children of all ages,” she said.
Moderna released a summary of the results, which have not yet been published in a peer-reviewed journal.
The announcement comes a day before an FDA advisory panel is scheduled to discuss data on Pfizer-BioNTech’s COVID-19 vaccine for 5- to 11-year-olds.
The FDA authorized the Pfizer-BioNTech vaccine for 12- to 15-year-olds in May.
Moderna said it is still enrolling children ages 6 months to 5 years old for other trials, noting it has enrolled about 5,700 children in the U.S. and Canada.
The vaccine manufacturer previously requested the FDA grant emergency use authorization for the vaccine to be administered to 12- to 17-year-olds in June, but the agency has not yet acted on that application.
The submission followed Moderna’s data showing the COVID-19 vaccine was 100 percent effective against infections in that age group.
Updated at 11:18 a.m.
