Two Top F.D.A. Vaccine Regulators to Depart This Fall

The F.D.A. is also expected soon to tackle the question of whether to authorize coronavirus vaccines on an emergency basis for children under 12. Last week, the agency fully approved the Pfizer-BioNTech vaccine for people 16. Older, a major decision that spurred a series of vaccine mandates at corporations, universities, hospitals, and elsewhere. That decision…