Pfizer said Friday it's going to test three doses of its COVID vaccine in young children under five years old, after two jabs failed to produce the expected immunity in babies and preschoolers.
Two doses didn't appear strong enough in some of the kids, the company said, saying that a preliminary analysis found 2- to 4-year-olds' immune response wasn't as strong as expected to the lose-dose jabs for younger children.-- More...
