Margaret Hamburg, MD, the commissioner of the U.S. Food and Drug Administration (FDA), announced her resignation via a letter to her colleagues on Thursday.
Dr. Hamburg, the second woman to be nominated for the top position, has led the FDA since 2009 and is one of the longest-serving commissioners.
During Dr. Hamburg's guidance, the FDA issued a final regulation on dental amalgam, classifying it from a class I (least risk) to a class II (more risk) device. The FDA also recently advised clinicians to avoid off-label use of certain bone graft substitutes in patients younger than 18 because of the risk for serious injury.
There is published speculation from multiple national newspapers that Robert Califf, MD, who Hamburg appointed as deputy commissioner for medical products and tobacco last month, may become the next commissioner.