Dr. Peter Marks, a top Food and Drug Administration vaccine official, resigned under pressure on Friday, stating that Robert F. Kennedy Jr.’s aggressive attitude towards vaccines was irresponsible and posed a risk to public health.

“It became clear that truth and transparency are not valued by the secretary, but instead he desires blind confirmation of his misinformation and lies,” Dr. Marks wrote to Sarah Brenner, the agency’s representative. He reiterated his sentiments in an interview, stating, “This individual does not prioritize truth. He prioritizes followership.”

Dr. Marks resigned after being called to the Department of Health and Human Services on Friday afternoon, where he was given the ultimatum of resigning or being terminated, according to sources familiar with the situation.

Dr. Marks headed the Biologics Evaluation and Research Center responsible for approving and monitoring vaccine safety, as well as a variety of other therapies including cell and gene therapy. He was viewed as a steady and reliable presence by many during the pandemic, despite facing criticism for being overly accommodating to businesses seeking approval for treatments with complex evidence of effectiveness.

Ongoing scrutiny of the FDA’s vaccine program clearly placed Dr. Marks at odds with the new health secretary. Since Kennedy took office on February 13th, he has issued a series of directives on vaccine policy. He has alarmed those concerned about his potential to leverage his government authority to advance his long-standing campaign asserting vaccines are highly detrimental despite overwhelming evidence of their life-saving impact worldwide.

“Undermining trust in a well-established vaccine that has met the FDA’s rigorous standards of quality, safety, and efficacy for decades is irresponsible and poses a significant risk to public health and our nation’s well-being and security,” Dr. Marks wrote.

For instance, Kennedy promoted the use of vitamin A as a treatment during a major measles outbreak in Texas, downplaying the importance of vaccination. He has surrounded himself with analysts tied to the anti-vaccine movement and is pursuing studies examining long-debunked theories linking vaccines to autism.

On Thursday, Kennedy announced plans to establish a vaccine injury agency within the Centers for Disease Control and Prevention. He emphasized that this initiative was a top priority and would bring the “gold standard of science” to the federal government.

An HHS spokesperson stated on Friday night that Dr. Marks would no longer have a place at the FDA if he did not commit to transparency.

In his resignation letter, Dr. Marks highlighted the tragic toll of measles amid Kennedy’s lukewarm approach to the urgent vaccination needs among many unvaccinated individuals in Texas and other states.

Dr. Marks pointed out that through widespread vaccine availability, “over 100,000 children who received vaccinations last year in Africa and Asia were saved.”

Dr. Marks expressed his willingness to address Kennedy’s vaccine safety and transparency concerns in public forums and through collaboration with national experts in science, engineering, and medicine, which he was rebuffed.

“I have exhausted all efforts to work with them to restore confidence in vaccines,” Dr. Marks stated in an interview. “It became evident that this was not their goal.”

With that, Dr. Marks bid farewell to the FDA.

“His leadership has been instrumental in driving medical innovation and ensuring life-saving treatments reach those in need,” stated Ellen V. Sigal, founder of the cancer research advocacy group Friends and a close associate of Dr. Marks. His departure, she noted, “will leave significant gaps.”

Dr. Marks guided the agency and its external advisors on the type of evidence required to pilot the FDA’s vaccine program amid the tumultuous year of the coronavirus pandemic and expedite emergency authorizations for vaccines developed under the Trump administration’s Operation Warp Speed.

In June 2022, he urged an external expert panel to consider the risks the virus posed to children under five years old, leading the panel to recommend the vaccine for that age group later that day.

“We must be cautious not to be paralyzed by the number of pediatric deaths due to the overwhelming number of fatalities we are facing here,” Dr. Marks cautioned at the time.

Dr. Peter Hotez, a vaccine expert at Baylor College of Medicine, spoke highly of his regular interactions with Dr. Marks during the pandemic, describing him as deeply committed to leveraging science to aid the American populace. “He was a pandemic hero, and it’s truly unfortunate to see him go,” Hotez remarked.

Dr. Marks faced skepticism from some within the FDA, including former members of his own vaccine team. Two senior regulators in the agency’s vaccine office resigned in 2021 over the Biden administration’s efforts to push for the approval of Pfizer’s COVID-19 vaccine and booster shot.

Kennedy’s call for further investigation into vaccine injuries was met with reservations by Dr. Michael Osterholm, director of the University of Minnesota’s Center for Infectious Disease Research and Policy, who noted that such research had been a focal point for decades. “I fear this is an attempt to magnify vaccine harm out of proportion to the actual risk,” Osterholm cautioned.

Dr. Marks shared these concerns, expressing his desire in his letter to mitigate the harm inflicted by the current administration.

“My hope,” he penned, “is that the unprecedented assault on scientific truths that has detrimentally impacted our nation’s public health will cease in the coming years, allowing our citizens to fully benefit from the wide array of medical advancements.”