Vaccine Makers Are Asked to Expand Safety Studies on Children July 26, 2021 Auto Bot Children and Childhood, Clinical Trials, Coronavirus (2019-nCoV), Food and Drug Administration, Moderna Inc, Pfizer Inc, Vaccination and Immunization 0 The F.D.A. wants Pfizer and Moderna to increase the number of 5- to 11-year-olds who participate in trials of their coronavirus vaccines to ensure there is enough data about rare side effects.