If Pfizer's data pans out, when will little kids get the COVID-19 vaccine?

Pfizer will submit new data to the FDA this week about trials of its vaccine for kids younger than 5 years old. Here, a girl holds her sister's hand as a nurse prepares to administer the COVID-19 vaccine at a vaccination clinic in Los Angeles. Kids 5 and older have been eligible for the vaccine since last November. (Robyn Beck/AFP via Getty Images)

A third pediatric dose of the Pfizer-BioNTech COVID-19 vaccine in children 6 months to under 5 years of age prompted a strong immune response, with a safety profile that was similar to placebo, the companies said.

Pfizer's pediatric COVID-19 vaccine has an efficacy of 80.3%, according to a preliminary analysis, and meets "all immunobridging criteria required for Emergency Use Authorization," the company said Monday. The results are based on clinical trials in which kids from six months to age 5 got three doses of the company's vaccine.