Dr. Vinay Prasad, the Food and Drug Administration's chief science and medical officer, is leaving the agency at the end of April after a brief but tumultuous tenure. The polarizing figure had wide-ranging authority over vaccines, drugs, and gene therapies but faced criticism for rejecting drug applications and overruling career scientists. His departure follows months of controversy over his handling of drug approvals.

Prasad's most high-profile move came when he refused to accept Moderna's application for an mRNA flu vaccine, causing an uproar among companies and experts who said he was moving the goalposts on studies already approved by the agency. FDA Commissioner Dr. Marty Makary later reversed that decision. In recent months, Prasad issued a series of rejections for rare disease treatments, upsetting patients and biotech companies.

His tenure was marked by threats against employees who might leak information and public invitations for staff who disagreed with him to resign. Prasad was briefly dismissed last summer after right-wing influencer Laura Loomer attacked him for past statements favoring Democrats, but was quickly reinstated at the insistence of Makary and Health Secretary Robert F. Kennedy Jr. The Wall Street Journal first reported his planned departure.