Moderna has dosed its first participants in its Phase 2/3 study — otherwise known as KidCOVE study —which includes children as young as six months old, the company said Tuesday in a statement.

The Massachusetts-based biotech company is the first to enroll infants and toddlers in a clinical trial for a COVID-19 shot. Moderna's current vaccine is only authorized for people 18 and older.

"We are pleased to begin this Phase 2/3 study of mRNA-1273 in healthy children in the U.S. and Canada," Moderna CEO Stephane Bancel said in a press release. "This pediatric study will help us assess the potential safety and immunogenicity of our COVID-19 vaccine candidate in this important younger age population."

"Phase 2/3 study expected to enroll 6,750 healthy pediatric participants less than 12 years of age" in the U.S. and Canada, the company said.

Moderna’s study involves each child receiving two shots, 28 days apart.

In the trials' first stage, those between the ages of 2 and 12 may receive two doses of 50 or 100 micrograms each. Those under 2 years old may receive two doses of 25, 50 or 100 micrograms. An adult dose is 100 micrograms.

The trial's first-enrolled children will receive the lowest doses and will be monitored for symptoms and reactions.

The 6,750 participants will be followed for a year after receiving their second Moderna vaccination at the end of the trial.

“There’s a huge demand to find out about vaccinating kids and what it does,” Dr. David Wohl, the medical director of the vaccine clinic at the University of North Carolina, told the New York Times.

Moderna did not provide an update on testing efforts for those between the ages of 12 and 18.

Pfizer/BioNTech is also conducting a trial on children. Johnson & Johnson will have a study for those between the ages of 12 to 18.

"We project that high school students will very likely be able to be vaccinated by the fall term, maybe not the very first day, but certainly in the early part of the fall for that fall educational term," Dr. Anthony Fauci told CBS News' "Face the Nation" on March 7.

"Elementary school kids, we're doing this what's called age de-escalation studies to make sure it's safe and immunogenic in them. They likely will be able to get vaccinated by the very first quarter of 2022," he said.

Some ten percent of Americans have so far received at least one Covid vaccine dose, with Moderna accounting for just under half the number
Moderna logo. AFP / JOEL SAGET