Dr. Vinay Prasad, the Food and Drug Administration’s top vaccine and biotechnology regulator, will leave the agency at the end of April — his second departure in less than a year — FDA Commissioner Marty Makary announced in an email to staff late Friday. Makary said Prasad would return to his faculty position at the University of California, San Francisco.
The announcement follows a string of high-profile disputes between the FDA and pharmaceutical companies over vaccine approvals and treatments for rare diseases, including a public fight with Moderna over an mRNA flu vaccine and a clash with a gene-therapy company developing an experimental treatment for Huntington’s disease.
Prasad’s exit marks the second time in under a year that the FDA’s chief regulator of vaccines and biotech drugs has left under pressure, deepening uncertainty about the agency’s regulatory direction at a time when multiple companies have criticized the FDA for reversing positions on previously approved products and demanding costly new trials.
Moderna flu vaccine dispute
In the most prominent recent controversy, Prasad initially refused to allow the FDA to formally review a highly anticipated flu vaccine from Moderna made with mRNA technology — a rejection that was described as highly unusual for the agency. After Moderna went public with the decision and vowed to formally challenge it, the FDA reversed course within a week and said it would accept the shot for review, pending an additional study from Moderna.
Huntington’s disease therapy fight
In the past week, the FDA became involved in a highly unusual public fight with UniQure, a small drug company developing an experimental gene therapy for Huntington’s disease, a fatal condition that affects about 40,000 people in the United States. UniQure said Monday that the FDA was demanding a new trial of its therapy that would involve performing a sham surgery on some of the patients. The company’s gene therapy is injected directly into the brain during a surgical procedure.
UniQure executives said the request for a sham-controlled trial contradicted previous FDA guidance and raised ethical concerns for patients.
On Thursday, the FDA held what the Associated Press described as a highly unusual press conference with reporters to criticize the company’s therapy and defend the agency’s request for additional study — a departure from the FDA’s typical practice of communicating through carefully vetted written statements in scientific disputes involving drugs still under review. A senior FDA official, who requested anonymity to speak with reporters, called UniQure’s original study “stone cold negative” and added, “We have a failed product here.”
Earlier ouster and reinstatement
Prasad’s first departure came in July, when he was briefly pushed out after running afoul of biotech executives, patient groups, and conservative allies of President Donald Trump. He was reinstated less than two weeks later with the backing of Health Secretary Robert F. Kennedy Jr. and Makary.
Since joining the FDA, Prasad’s tenure has drawn criticism from multiple directions. More than a half-dozen drugmakers studying therapies for rare or hard-to-treat diseases received rejection letters or requests to run additional studies, adding years and potentially many millions of dollars to their development plans, according to the Associated Press.
At the same time, Prasad and Makary jointly announced on repeated occasions steps intended to make FDA drug reviews faster and easier for companies. Prasad also imposed new warnings and study requirements for some biotech drugs and vaccines, particularly COVID shots that have been a longtime target of Kennedy, who was a prominent vaccine skeptic before joining the Trump administration.