Pfizer announced Wednesday it has begun phases 2 and 3 of its pediatric clinical trial for Paxlovid, its COVID-19 antiviral treatment.

The study will look into how effective and safe the treatment is for children between the ages of 6 and 17.

The FDA has already authorized Paxlovid for high-risk people who are 12 years or older and weigh at least 88 pounds.

However, the data used for approval did not include people under the age of 18.

Adult trials showed that the antiviral treatment reduced the risk of hospitalization or death by 89% among high-risk adults, according to Pfizer.

The company says data from this new trial will “provide further support for the dose recommendations in this population, as well as potentially expand the indication to younger age groups and lower weights."

Pfizer hopes to enroll 140 participants in the trial.

Researchers at Pfizer are also working on formulating an appropriate dose for children as young as 6 years old.

They will eventually begin trials for a younger child group when the appropriate dose is determined.