FDA's top vaccine regulator to leave in April

The Food and Drug Administration's top vaccine regulator will leave the agency at the end of April, a Department of Health and Human Services spokesperson confirmed to Axios.

Why it matters: Vinay Prasad, director of FDA's Center for Biologics Evaluation and Research, has presided over controversial decisions including declining to review Moderna's new mRNA flu vaccine approval application — a decision that was later reversed.

• FDA Commissioner Marty Makary posted on X that the agency will name a successor before Prasad leaves.

The big picture: The news could bring some relief to biotech companies and investors, who've been concerned about the regulatory agency's lack of predictability.

• Prasad's division has come under fire most recently for rejecting approvals for multiple rare disease drugs, which critics said went against the Trump administration's pledge to increase regulatory flexibility in the space.
• He also called for tighter oversight on vaccines, including more restrictions on new products. In a memo to FDA staff last year, he said an unpublished agency review linked COVID-19 vaccines to the deaths of 10 children, without supplying underlying data.
• Prasad made a name for himself on social media during the pandemic as a critic of the government's response.

What they're saying: Prasad only intended to stay at the FDA for a one-year leave of absence from his post at the University of California -San Francisco, per the Wall Street Journal, which first reported the news.

• Prasad unexpectedly left the FDA once before, in July amid tensions over gene therapy decisions. He returned weeks later to head the agency's biologics division.
• He has also been serving as FDA's chief medical and scientific officer.

What we're watching: Whether FDA reconsiders applications for rare disease drugs it recently denied, like UniQure's investigational gene therapy for Huntington's disease.

Editor's note: The story has been updated with additional reporting.