WASHINGTON — Drug-maker Moderna says it has a COVID-19 shot that works in kids under six, and is planning to ask the FDA to approve it. This would be the first vaccine against the virus for children in that age group.
But it takes a lot more than a big company's word to approve vaccines for little ones. So we're verifying what the vaccine approval process looks like for children.
THE QUESTION
What does it actually take to get vaccines approved for children?
THE SOURCES
- Dr. Alexandra Yonts, an infectious disease specialist with Children’s National Hospital
- The CDC
- The FDA
- Pfizer
- Moderna
THE PROCESS
With any new vaccine, the FDA looks at the data to determine if a shot is safe and effective, and the CDC decides whether or not to recommend it. In most vaccines, including those against COVID-19, this happens first with a study of adults.
“The trials are usually not as large, because efficacy has been established, and there's no thought that it should be different," Dr. Yonts said. “And then there is a larger number of patients that are looked at for safety purposes. So observe for adverse effects, continue to follow for two years, you know, as the study progresses, so that part isn't any smaller necessarily than the adult studies.”
As of February, Pfizer says its trial included about 8,300 children between ages 6 months to 12-years-old. Moderna’s site lists 13,275 participants in the same age group for their study. Those are a fraction of the size of each company’s clinical trials in adults: Pfizer has 46,330 and Moderna has 30,000.
Since the adult studies establish vaccine safety, trials for kids determine how much vaccine is needed to still work.
“As we've learned, dosing matters," Yonts said. "And that's been one of the biggest issues with pediatric vaccines.”
Because a 2-year-old and a 10-year-old are very different developmentally, it's up to researchers to determine the lowest amount of vaccine that can be given to a kid that's still effective.
After a shot at proper dosage is greenlit, the CDC's "Advisory Committee on Immunization Practices" places it on the official American vaccine schedule---laying out what vaccines are needed at what ages.
"It very well could end up being something that gets on the annual schedule, at least like an influenza vaccine," Yonts said. "Or if we see after a year or two that really SARS COV2 isn't going anywhere, there's potential for it to be an addition to the regular childhood vaccine process. But I think that data is still kind of coming in, we're still trying to sort that out."
Dr. Yonts said the approval process includes plans to monitor trial participants for decades after their vaccines. She says current data proves to her that the COVID-19 shots are a good idea for most kids during this ongoing pandemic.