U.S. Food and Drug Administration (FDA) Commissioner Dr. Marty Makary has resigned after months of mounting pressure from the Trump administration, marking a major leadership shake-up at one of the country’s most influential health agencies.

President Donald Trump announced the resignation on Truth Social, sharing a text message from Makary in which the outgoing commissioner reflected on his tenure and thanked the president for the opportunity to serve.

“It’s been the honor of a lifetime to serve as your FDA Commissioner,” Makary wrote. “I am forever grateful.”

Makary, a former surgical oncologist and professor at Johns Hopkins University School of Medicine, served as FDA commissioner for just over a year. During his time in office, he pushed several controversial reforms and regulatory changes that drew both praise and criticism across the healthcare and political spectrum.

In his resignation message, Makary pointed to what he described as key accomplishments, including faster drug review processes, new guidance supporting psychedelic therapies, and the creation of a “plausible mechanism pathway” aimed at accelerating approval of treatments for rare diseases.

He also highlighted efforts to revise labeling on menopausal hormone replacement therapies to better inform women about potential risks and benefits.

Reports suggest Trump had approved plans to remove Makary from the position last week, following rumors of tensions within the administration that had circulated since late 2025.

Speaking about the resignation, Trump said Makary had faced “some difficulty” in the role but praised him as “a great doctor.”

“He’s going to go on and he’s going to lead a good life,” Trump said. “He’s a great doctor. He’s going to go on and do well. Everybody wants that job.”

Makary’s leadership became increasingly controversial during his tenure. He faced criticism over his resistance to approving flavored e-cigarette products and also drew backlash from some Republican lawmakers and anti-abortion groups, who accused the FDA of moving too slowly on a safety review involving the abortion pill mifepristone.

Some industry leaders acknowledged Makary’s ambitious approach to reforming drug regulation but questioned whether he was the right fit to manage the agency.

“He was creative and ambitious with ideas to speed up drug development,” said Dr. Roderick Wong, managing partner of biotech hedge fund RTW Investments.

However, Wong also argued that Makary ultimately bore responsibility for leadership struggles within the FDA, including criticism surrounding Dr. Vinay Prasad’s management of the Center for Biologics Evaluation and Research and difficulties filling top positions within the Center for Drug Evaluation and Research.

Following Makary’s departure, Kyle Diamantas, the FDA’s top food regulator, will take over as acting commissioner while the administration searches for a permanent replacement.

Diamantas’ appointment has already sparked debate because, unlike most FDA commissioners, he does not have a medical or scientific background.

“Kyle Diamantas now has a nearly impossible charge — leading, as a non-scientist, a science-based agency under an unqualified secretary who puts his own medical and nutritional pet peeves over evidence-based public health,” said Peter Lurie, director of the Center for Science in the Public Interest.

It remains unclear how long Diamantas will serve in the acting role or who Trump may eventually nominate to permanently lead the FDA.