Dr. Vinay Prasad, a hematologist and an oncologist, has been named by the US Food and Drug Administration (FDA) to head its Center for Biologics Evaluation and Research, the division that oversees vaccines and biologic medicines. Vinay Prasad replaces Dr Peter Marks, who helped to grow the division for the last 13 years and shaped the Operation Warp Speed effort to rapidly develop COVID-19 vaccines and treatments.

He authored books in the medical field in 2015 and 2020.

Prasad incurred controversy by criticising the government’s response and its vaccine policies during the COVID-19 pandemic. He questioned authorizing those shots for children, because they are at lower risk of severe infection than older people and those with weakened immune systems.

He also questioned FDA’s decision to approve Sarepta’s Elevidys, a multimillion-dollar gene therapy to treat Duchenne muscular dystrophy, despite what he saw as limited evidence of its benefits. He had co-written a post last year that slammed the FDA, “Despite its high cost and potential toxicity, the clinical benefits of Elevidys remain uncertain.”

Biotech stocks tumbled more than five percent following the announcement by calling Prasad an “anti-establishment” choice, stating that he has also questioned the FDA’s use of accelerated approval processes for certain medicines.

Prasad’s appointment to lead the Center for Biologics Evaluation and Research comes as the FDA says it will impose new requirements for future vaccines to undergo placebo studies.

Under his leadership, the biologics division could bring more scrutiny and requirements to developers creating new gene therapies. Earlier this year, Prasad said he wanted to see more stringent reviews. On X, he wrote, “The FDA did nothing to speed gene therapy, other than talk about how they will use uncontrolled endpoints. But we want to speed effective gene therapy, not ineffective gene therapy. The FDA had no solution for that.”