Drugmaker Moderna plans to study Canadian children during an upcoming clinical trial on its COVID-19 vaccine.

The study will involve more than 6,700 healthy children both here and in the U.S., ranging in age from just six months to 12 years old.

Moderna says initial participants are based in the United States but that Canadian sites will be added as the trial progresses. The company says it hasn’t yet chosen the Canadian sites, nor Canadian participants.

It will evaluate the safety and effectiveness of two doses given 28 days apart and Moderna will track the children for a year after they get the second shot.

In addition to Moderna, Canada has approved vaccines by Pfizer-BioNTech and Oxford-AstraZeneca for adult use, although the Pfizer product can be used by people as young as 16.