FDA’s Top Vaccine Scientist Resigns Because of Robert F. Kennedy Jr.’s ‘Misinformation’

Dr. Peter Marks, one of the U.S. Food and Drug Administration’s (FDA) top vaccine officials, has resigned.

In a resignation letter dated Friday, March 28, which was obtained by KFF reporter Stephanie Armour and shared on X, Marks cited the work done by U.S. Department of Health and Human Services (HSS) Secretary Robert F. Kennedy Jr. as one of the reasons for his resignation. 

“It has become clear that truth and transparency are not desired by the Secretary, but rather he wishes subservient confirmation of his misinformation and lies,” the physician wrote.

In response to Marks’ resignation, an HSS spokesperson told NBC News and The Wall Street Journal in a statement: “If Peter Marks does not want to get behind restoring science to its golden standard and promoting radical transparency, then he has no place at FDA under the strong leadership of Secretary Kennedy.”

The HSS did not immediately respond to PEOPLE’s request for comment on Saturday, March 29.

Several sources familiar with the situation told NBC News, the WSJ and NPR that Marks was forced out of his position and was given a choice to either send in his resignation or be fired. 

Marks has worked as director for the FDA’s Center for Biologics Evaluation and Research since 2016, according to his online biography. He previously joined the organization in 2012 as deputy director.

That branch of the FDA is responsible for “assuring the safety and effectiveness of biological products, including vaccines,” according to the group’s website.

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Sources told the WSJ that Marks attempted to work with Kennedy, 71 — who has been critical of vaccines, including one for COVID-19 — after his confirmation as HHS Secretary last month.

Marks reportedly sent a memo to the politician proposing listening sessions on immunizations and holding public meetings with the National Academy of Sciences and Engineering and Medicine, the outlet reported.

Marks is known for helping launch Operation Warp Speed, which worked to quickly authorize the first COVID-19 vaccines for usage in 2020 under Donald Trump‘s first presidential administration.

As for Kennedy, his office is currently focused on the measles outbreak in the U.S. However, he has faced backlash for comments he previously made about the health ordeal, including when he called it “not unusual.”

The son of Robert F. Kennedy and Ethel Kennedy also said in an interview on Fox News with Sean Hannity that the measles-mumps-rubella vaccine “does cause deaths every year.”

Kennedy previously criticized the COVID-19 vaccine, calling it the “deadliest vaccine ever made.” He has also said in the past that he thinks vaccines are a “personal” decision.

Marks is the third top leader at the FDA to leave in 2025. The Center for Drug Evaluation and Research’s Dr. Patrizia Cavazzoni and Human Foods Program Chief Jim Jones also resigned earlier this year.