The Food and Drug Administration’s leading vaccine official, Dr. Peter Marks, submitted his resignation on Friday, citing fundamental disagreements with Health and Human Services Secretary Robert F. Kennedy Jr.’s stance on vaccine-related matters.
In his resignation letter to acting FDA Commissioner Sara Brenner, Marks expressed frustration with Kennedy’s approach to vaccine policy and public health messaging. “Despite attempts to address concerns about vaccine safety and transparency, it has become evident that the Secretary is not interested in factual information, but rather seeks to promote misleading narratives,” Marks stated in the letter obtained by BioPharma Dive.
The departure of Marks, who has led the FDA’s Center for Biologics Evaluation and Research since 2016, comes amid broader leadership changes at the agency. His exit will create vacancies in both of the FDA’s main drug review divisions, following the January departure of Patrizia Cavazzoni.
Marks played a crucial role in the development and implementation of Operation Warp Speed during the first Trump administration, which accelerated the creation and distribution of COVID-19 vaccines. Throughout his tenure, he has been a strong advocate for cell and gene therapy advancement, often pushing for increased regulatory
flexibility.
The resignation comes as the United States grapples with a significant measles outbreak that has affected 483 individuals across 20 states and resulted in the first U.S. measles death in a decade. In his letter, Marks specifically addressed Kennedy’s handling of the outbreak, criticizing the promotion of unproven treatments like cod liver oil while questioning established vaccine safety.
“The undermining of public confidence in scientifically-validated vaccines that have met rigorous FDA standards poses a serious threat to public health and national security,” Marks wrote.
Former FDA Commissioner Robert Califf praised Marks’ service on Bluesky, noting that while his decisions sometimes sparked debate, his primary focus was always public health advancement and patient care in an evolving technological landscape.
The biotechnology industry has expressed concern about the leadership vacuum. John Crowley, who heads the biotech advocacy group BIO, warned that the loss of experienced leadership could compromise scientific standards and impede therapeutic innovation.
The resignation coincides with broader changes at HHS under the Trump administration, including recently announced plans to reduce the department’s workforce by approximately 10,000 positions. This restructuring includes significant staff reductions at both the CDC and FDA, with 2,400 and 3,500 positions to be eliminated respectively.
These developments occur as Martin Makary, President Trump’s nominee for FDA commissioner, received Senate confirmation, though his official appointment status remains unclear.
Kennedy, who has historically promoted controversial views about vaccine safety, has faced criticism for his approach to public health policy since assuming the role of HHS Secretary. His administration of vaccine advisory committees has drawn particular scrutiny, with reports from Politico suggesting potential changes to advisory panel membership and delayed committee meetings.
Marks’ departure, effective April 5, represents a significant shift in FDA leadership during a critical period for public health policy. His resignation letter concluded with a call for an end to what he described as “an unprecedented assault on scientific truth” that he believes has negatively impacted American public health outcomes.
The two-dose measles vaccine currently available in the United States maintains a 97% effectiveness rate in preventing the disease, with minimal side effects reported in most cases. Scientific evidence has consistently refuted claims linking the vaccine to autism, despite Kennedy’s long-standing assertions to the contrary.