Two senior FDA officials are resigning from the agency, according to an FDA spokesperson. According to several sources, their decision is in part due to frustration with the Biden administration's announcement on Covid-19 booster shots.

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FDA officials resign

According to an FDA spokesperson, Marion Gruber, director of FDA's Office of Vaccines Research & Review, and Phil Krause, deputy director of the vaccines office, will retire this fall. According to the New York Times, both Gruber and Krause—who have both been at the agency for 30 years and have considerable expertise in reviewing vaccine data—were leading teams tasked with issuing recommendations regarding the Covid-19 vaccines.

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In a memo, Peter Marks, head of FDA's vaccine division, praised Gruber and Krause's work, saying it "has positively impacted the public health in the United States and across the globe." Marks added that he would serve as acting director of the vaccines office until FDA hires a new leader.

Separately, acting FDA Commissioner Janet Woodcock sent a memo to vaccine regulators at FDA thanking Gruber and Krause for their service and saying that they have her "full support and complete confidence."

Disagreements within FDA over booster shots

According to what sources told Axios, Gruber and Krause are leaving partly because they feel FDA has been sidelined by the White House. Endpoints reports that "what finally did it for them was the White House getting ahead of FDA on booster shots."

Sources told Politico that, so far, there has not been much coordination between the different federal health agencies regarding the plan for booster shots. President Joe Biden said he wants to make booster shots available to all Americans eight months after their second dose—pending CDC recommendation and FDA approval.

It was "the administration's booster plan; it wasn't the FDA's booster plan," said Paul Offit, an infectious disease expert at the University of Pennsylvania who is part of FDA's vaccine advisory committee. "The administration has kind of backed themselves up against the wall a little bit here."

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According to the New York Times, sources say Gruber and Krause were not comfortable with that approach, especially because they do not believe the data yet supports such a plan. (CDC's advisory panel yesterday, for instance, indicated it was leaning toward a risk-based approach when it comes to allocating booster shorts.)

Other experts have argued that even though Biden's plan depends on FDA approval and a CDC recommendation, it puts the agencies in a difficult position because it forces them to determine whether booster shots are safe and effective after the shots have already been endorsed by both the White House and Woodcock.

"This process has been the reverse of what we would normally expect in vaccine policy," with Biden's administration unveiling plans—pending review—before federal agencies can complete that review, said Jason Schwartz, an associate professor of health policy at the Yale School of Public Health. "That has made it even more complicated and confusing for the public."

Separately, a senior administration official agreed that it's "really awkward." The official added, "[W]e have to plan as if we're going to do this before we even have the data. And sure, the scientists are thinking that isn't the right way to do it, but there is no other way to do it."

"That doesn't mean we act if the data don't support it, but we do have to plan," the official said. "It's awkward for the scientists. They don't like that. But they don't have to plan how to vaccinate 200 million people."

For their part, officials at the White House have said the booster shot plan received support from all senior health officials in the government, including Woodcock, and a booster plan is needed in light of data showing vaccines wane in effectiveness over time.

Data from around the world has "actually led us to be even more concerned about increased risk of vaccine effectiveness waning against hospitalization, severe disease, and death," CDC Director Rochelle Walensky said.

Sources familiar with the Biden administration's thinking told Politico that Biden and his top health aides—including Jeffrey Zients, White House Covid-19 response coordinator, and Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases and chief medical advisor to the White House—wanted to prepare the American public for booster shots so they'd be ready for them when they were necessary.

"As our medical experts laid out, having reviewed all the available data, it is in their clinical judgment that it is time to prepare Americans for a booster shot," Zients said. "We announced our approach in order to stay ahead of the virus, give states and pharmacies time to plan, and to be transparent with the American people." (Owens, Axios, 9/1; Weiland/LaFraniere, New York Times, 8/31, Weixel, The Hill, 8/31; Owermohle, Politico, 8/31)