(The Hill) – Vinay Prasad, who served as the leading vaccine regulator and chief scientific officer at the Food and Drug Administration (FDA) and was known for critiquing the agency’s COVID-19 strategies, has stepped down after a tenure of under three months.

A spokesperson from the Department of Health and Human Services (HHS) explained in an emailed statement, “Dr. Prasad has chosen to depart in order to avoid distracting from the FDA’s important work during the Trump administration. He plans to return to California to spend more time with his family. We appreciate his service and the significant reforms he contributed during his period with the FDA.”

The spokesman did not say who would replace Prasad or provide a reason for his sudden departure. 

Prasad’s departure happens amidst growing criticism from conservative voices, including activist Laura Loomer and former Senator Rick Santorum (R-Pa.), which coincided with a regulatory disagreement concerning a new gene therapy for boys with Duchenne muscular dystrophy.

Loomer, an external activist with notable influence on President Trump, has recently criticized Prasad through social media and her website. She labeled him a “saboteur” and a “trojan [sic] horse” within the administration’s “Make America Healthy Again” campaign.

She wrote on her website, “Prasad was not the reformist ally anticipated by the Trump administration; his liberal views, vocal criticism of Trump, and actions which seem to counter the President’s deregulatory goals make him unsuitable for such a pivotal role.”

Santorum echoed these sentiments, asserting on the social media platform X that Prasad was “endangering @POTUS legacy in relation to aiding patients.”

A few days later, a Wall Street Journal opinion column labeled Prasad “a young disciple of Bernie Sanders” and accused him of “scuttling potentially life-saving therapies.” 

Prasad was named head of the FDA’s Center for Biologics Evaluation and Research in early May as a replacement for Peter Marks, the longtime leader of division who resigned in March after clashing with HHS Secretary Robert F. Kennedy Jr.  

Prasad’s division has been involved in a regulatory dispute in recent weeks with Sarepta Therapeutics, the manufacturer of a gene therapy for Duchenne muscular dystrophy. The FDA forced Sarepta to stop all shipments of its treatment and halt clinical trials after the deaths of two patients who received the drug.  

Prior to his role at FDA, Prasad had been an outspoken critic of the agency’s initial decision to approve the treatment. The administration granted accelerated approval for Elevidys in June 2023 despite dubious evidence of its effectiveness to stop or reverse symptoms of the rare, fatal genetic disorder. To grant the approval, Marks unilaterally overrode multiple agency review teams that recommended against it. 

On Monday, the agency issued a statement partially reversing itself, removing the pause for patients who can still walk. 

Prasad was a key ally of FDA Commissioner Marty Makary, with whom he recently worked to narrow the approval for updated COVID-19 vaccines.  

Instead of recommending the shots for everyone, Prasad said they will only be approved for use in adults 65 and older and people at high risk for severe disease. 

In an interview with Politico published last weekend, Makary defended Prasad. 

“There’s not a political bone to his body,” Makary said. “He’s an impeccable scientist, I think one of the greatest minds of our generation.”