Vinay Prasad, an oncologist and professor of epidemiology at the University of California, San Francisco, served as the director of the Center for Biologics Evaluation and Research (CBER) and the FDA's chief medical and scientific officer. He joined the FDA on a year's unpaid leave from university and will leave at the end of April after a turbulent tenure full of controversy. He left briefly in July 2025 and returned 10 days later following a controversy over the safety of Sarepta Therapeutics' Elevidys gene therapy. During his tenure, he fired at least seven leaders, including the head of vaccine safety, leading to complaints of retaliation against subordinates and verbal abuse of employees. Under his leadership, the FDA rejected Moderna's application for mRNA flu vaccine mRNA-1010, later reversed under pressure from the White House, and rejected Disc Medicine's bitopertin. Prasad introduced stricter rules for approving COVID-19 vaccines, limited to those over 65 or with risk factors, and shortened clinical trial requirements. He helped create a new pathway for personalized medicine and a national priority rapid drug review program.[1][2][3][4]