Moderna's (MRNA  ) says a lower doses of its mRNA COVID-19 vaccine is safe and effective for children, including those under age 6, according to new data from clinical trials published Wednesday. The biotech plans to submit the data to the U.S. Food and Drug Administration (FDA) for emergency use authorization "in the coming weeks".

Moderna's vaccine is currently approved by the FDA for adults ages 18 years and older and authorized for use for adolescents above the age of 12. The company has also asked the U.S. health regulator to authorize its vaccine for children between the ages of 6-to 11-years old, the company said Wednesday.

"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 CEO Stephane Bancel in a press statement.

In clinical trials, two 25 microgram doses (a quarter of the dose authorized for adults) were given 28 days apart to 2,500 children ages 6 months to under 2 years and to 4,200 children ages 2- to under 6-years-old. The vaccine was found to be about 44% effective at preventing infection from the Omicron variant (the dominant COVID strain during the study) in children under 2-years-old and about 38% for children under 6-years-old, Moderna reports.

Despite the lower efficiency levels--Moderna's vaccine was found to be about 94% effective at preventing COVID infection from the original SARS-CoV-2 strain--the doses "showed a robust neutralizing antibody response" similar to adult doses, and had "a favorable safety profile," Moderna said.

In the study, no child developed severe illness due to COVID infection and the majority of breakthrough cases were mild, according to the biotech. Moreover, no deaths or cases of myocarditis, pericarditis or multisystem inflammatory syndrome were reported. Myocarditis and pericarditis are types of heart inflammations that have been observed at elevated rates following the second dose of Moderna's and rival Pfizer (PFE  )-BioNTech's (BNTX  ) vaccines, according to the U.S. Centers for Disease Control and Prevention (CDC).

Moderna said side effects in young children were also mild and more frequently reported after the second dose, which is similar to trials of older age groups. About 17% of kids under 2 years old developed a fever of 100 degrees Fahrenheit, while slightly more than 14% of kids 2- to 5-years-old developed a high fever. A fever higher than 104 degrees Fahrenheit was seen in only a few children in each age group, according to the company.

Children under 5-years-old are the only age group left in the United States not eligible for a COVID vaccine.