A recent FDA review found there was "insufficient data" regarding a factor of Pfizer's vaccine.
There isn't enough info to conclude whether Pfizer's coronavirus vaccine is safe for kids under 16.
There also isn't enough info regarding pregnant women and immunocompromised people.
Experts also worry about vaccinating people who previously got COVID-19, says Business Insider.
Some of these vulnerable groups were included in Pfizer's late-stage clinical trials, which are ongoing.
However, the FDA advisory committee has decided to recommend the shot for emergency use.
