Moderna Vaccine Up To 44% Effective Against Omicron In Kids Under 6

We seem to — finally — be one step closer to having a COVID-19 vaccine for our youngest children. On Wednesday, Moderna announced that interim data from its clinical trials in children ages 6 months to 6 years old met primary endpoints, and that it will seek FDA emergency use authorization for kids under 6.

In a study consisting of approximately 6,700 children ages 6 and under, the Moderna vaccine, administered in two 25 microgram doses 28 days apart, was 43.7% effective in preventing COVID-19 in children 6 months to 2 years old, and 37.5% effective in the 2 to 6 age group.

None of the children enrolled in the study developed severe symptoms, were hospitalized or were diagnosed with multisystem inflammatory syndrome (MIS-C). There were also no cases of myocarditis or pericarditis, an inflammation of the heart that had been reported in a small number of patients, primarily young men, after the second shot of the Pfizer or Moderna vaccines.

Because the study took place during the omicron surge, these findings presumably apply to infection with the omicron variant, and the lower rates of efficacy are consistent with observational data that omicron causes more breakthrough infections in adults.

In a statement, Moderna CEO Stéphane Bancel said he believes these results are “good news for parents of children under 6 years of age.”

“Given the need for a vaccine against COVID-19 in infants and young children we are working with the U.S. FDA and regulators globally to submit these data as soon as possible,” said Bancel.

Parents of kids under 5 have been left in limbo while the Pfizer vaccine was first approved for children 12 and up and then for ages 5 to 11. Throughout the disruptive omicron surge, families with young kids were left to navigate preschool and daycare without the protection of a vaccine.

Side effects of the Moderna vaccine were similar to those seen in older children, teens and adults. A fever over 38°C (about 100°F) was reported in 17% of children 6 months to 2 years old and 14.6% in children 2 to 6. This compares to a rate of 23.9% in children 6 to 12 years old, who receive two 50 microgram doses of the vaccine. Only a few of the children enrolled in this study developed a fever of 40°C (104°F) and there were no deaths.

Moderna also announced that it is seeking FDA approval for the series of two 50 microgram shots in children ages 6 to 12, and for the series of two 100 microgram shots in ages 12 to 18. The Moderna vaccine for these ages groups has already been approved in Canada, Australia and some European countries.