Everything to Know about FDA's Personnel Shifts

Following the resignation of FDA Commissioner Marty Makary, the FDA has replaced the acting heads of its two primary product review centers, continuing a pattern of leadership instability that has characterized the agency under the second Trump administration.1 The changes affect the Center for Drug Evaluation and Research (CDER) and the Center for Biologics Evaluation and Research (CBER). The turnover raises practical questions about regulatory continuity and the pace of decision-making during what is already a complex period for the industry.

Tracy Beth Høeg, who had been serving as acting director of CDER, stated on social media that she was fired.1 Katherine Szarama, acting director of CBER, will depart her leadership role but remain at the agency. Michael Davis steps in to lead the drug evaluation center, while Karim Mikhail takes over the biologics division. Lowell Zeta has also been named acting chief of staff. The agency's official organizational chart was updated within days of the announcement.2

What Does Repeated Leadership Turnover Mean for Regulatory Timelines?

The leadership changes are not occurring in isolation.1 They follow the resignation of commissioner Marty Makary, who departed after reports emerged that President Trump sought to remove him from the position. A senior administration official has indicated that a new permanent commissioner nominee could be named within weeks, though that individual would still require Senate confirmation, which adds further uncertainty to the timeline. CDER has now seen several acting directors since January of last year, a level of churn that is unusual by historical standards.

How Stable Is the Broader Public Health Leadership Environment?

The situation at the drug and biologics centers reflects a wider vacancy problem across federal health agencies.1 The administration is simultaneously working to fill the director position at the CDC and the office of the surgeon general, suggesting that the leadership gaps extend well beyond the FDA's immediate remit.

Within CBER specifically, the past year has seen multiple individuals rotate through leadership, including Vinay Prasad, who left, returned, and ultimately departed again following a series of public controversies.3 That kind of instability in the division responsible for vaccine regulation creates difficulties for manufacturers navigating complex biologics pipelines, where long-term regulatory relationships and scientific consistency are closely tied to development strategy and investment planning.

The pharmaceutical industry's ability to plan around regulatory interactions depends heavily on predictable institutional structures.1 While the FDA's career staff provides a degree of continuity that political appointees do not, senior leadership sets the tone for enforcement priorities, review standards, and external engagement. Until a confirmed commissioner is in place and both centers have settled leadership, manufacturers and developers will need to be on top of the continuous rotation of the staff at the FDA, as the choices for those roles carry massive repercussions for the entire pharmaceutical industry.

References

1. Peebles A. FDA shuffles top drug, biologics leaders in latest shakeup. CNBC. May 15, 2026. https://www.cnbc.com/2026/05/15/fda-shuffles-top-drug-biologics-leaders-in-latest-leadership-shakeup.html
2. FDA overview organization chart. U.S. Food and Drug Administration. May 18, 2026. https://www.fda.gov/about-fda/fda-organization-charts/fda-overview-organization-chart
3. Peebles A. FDA vaccine head will step down in April after string of controversial decisions. CNBC. March 6, 2026. https://www.cnbc.com/2026/03/06/fda-vaccine-head-prasad-step-down.html