The nation's top vaccine regulator is stepping down — and he's not going quietly. Dr. Peter Marks, Director of the FDA’s ...

(CNN) — The head of the US Food and Drug Administration department responsible for assuring the safety and effectiveness of vaccines has resigned, according to a resignation letter obtained by CNN.

Kennedy Jr. in his resignation letter to acting FDA commissioner Sara Brenner, which The Washington Post has reproduced below. Read our story about the departure letters from veteran government ...