COVID-19 vaccines for kids under five may not come until next year.

Former FDA Chief Dr. Scott Gottlieb explains why.

"I think there is some indication based on the experience with this vaccine where FDA asked for additional information, as well as some feedback that Pfizer has gotten from the agency, that the clinical trials in kids ages six months to two years, and then two years to four years,” says Dr. Gottlieb.

Dr. Gottlieb went on to say, “So, it's two different trials, could be a little bit larger than a little bit longer in terms of the follow up period that's required. That could push it into 2022. Previously, we had talked about trying to have that data available before the end of this year, which could have prompted an authorization perhaps by the end of the year, at least in kids, ages two to four. I think that it's more likely that it slips into the first quarter of next year at the very least, but not too far into next year."

The FDA’s independent vaccine advisers will meet Oct. 26 to talk about vaccines for kids.