The Food and Drug Administration’s top vaccine regulator abruptly resigned Friday, citing what he called Health and Human Services Secretary Robert F. Kennedy Jr.’s efforts to spread misinformation about the safety of immunizations, according to a letter obtained by Bloomberg. Peter Marks, wh o was a key figure in Operation Warp Speed, stepped down from his position as the director of the FDA’s Center for Biologics Evaluation and Research, which is responsible for the safety and effectiveness of vaccines, along with gene therapies and blood products. “I was willing to work to address the Secretary’s concerns regarding vaccine safety and transparency,” he said. “However 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.”  Kennedy has openly questioned the safety of vaccines for years. Early in his tenure as health secretary, HHS has postponed and canceled meetings of outside vaccine experts, announced plans to study links between vaccines and autism and canceled funding to study vaccine hesitancy.  Read More: RFK Jr.’s First Defeat on CDC Chief Tests Vaccine Agenda Limits “The ongoing multistate measles outbreak that is particularly severe in Texas reminds us of what happens when confidence in well-established science underlying public health and well-being is undermined,” Marks said in his resignation letter Friday. “The vaccine very simply does not cause autism, nor is it associated with encephalitis or death.” An HHS official said if Marks doesn’t want to get behind Kennedy’s push for transparency, he shouldn’t stay at the FDA.  Marks said he didn’t agree with the direction of the new administration.  “Undermining confidence in well-established vaccines that have met the high standards for quality, safety, and effectiveness that have been in place for decades at FDA is irresponsible, detrimental to public health, and a clear danger to our nation’s health, safety. and security,” he said in his letter. HHS on Thursday announced mass layoffs of 10,000 employees across the federal agencies, which combined with buyout and early retirement programs will reduce the department’s workforce by around 25%. The agency said that employees who review drugs would not be laid off. Marks, who resigned effective April 5, has been director of the center since 2016.  The Wall Street Journal first reported Marks’ departure. This story was originally featured on Fortune.com ...read more read less