Top federal health officials on Tuesday defended the Biden administration's approach to coronavirus vaccine booster shots after two senior scientists in the Food and Drug Administration's (FDA) vaccine division announced their intent to leave the agency.
The announcement comes as FDA is weighing the evidence for coronavirus vaccine booster doses as well as shots for children.
It also comes amid fierce debate and criticism over whether the Biden administration is jumping ahead of the scientific review process in announcing boosters for everyone could be available by the week of Sept. 20.
Marion Gruber, director of the FDA’s Office of Vaccines Research & Review, and Phil Krause, the office's deputy director, will retire later this fall, according to an FDA spokeswoman.
The two scientists are the most senior vaccine regulators at the agency and both helped review the COVID-19 vaccines. Gruber, who has spent 32 years at FDA, will leave at the end of October. Krause, who’s worked at FDA for more than a decade, will leave in November.
The FDA is "confident in the expertise and ability of our staff to continue our critical public health work, including evaluating COVID-19 vaccines," spokeswoman Stephanie Caccomo said in an emailed statement.
FDA's Peter Marks, the head of the agency's vaccine division, praised Gruber and Krause for their service.
In a memo shared with The Hill, Marks said Gruber's work "has positively impacted the public health in the United States and across the globe."
Marks also thanked Krause "for his incredible contributions to public health over the course of his impressive career in the U.S. Public Health Service and with [Center for Biologics Evaluation and Research]."
Acting FDA Commissioner Janet Woodcock sent a memo to the agency's vaccine regulators, thanking them for their dedication and reiterating her "full support and complete confidence."
Woodcock added that she is confident that the agency has a plan "that will allow us to continue prioritizing science, while meeting timelines that are important to ensuring the end of this devastating pandemic."
When asked during a press conference whether he thinks the departures would undermine trust in FDA, White House coronavirus response coordinator Jeff ZientsJeff ZientsGOP senators say Biden COVID-19 strategy has 'exacerbated vaccine hesitancy' The Hill's Morning Report - Presented by Alibaba - Government shutdown fears increase as leaders dig in Travel industry hopes for rebound with loosened COVID-19 restrictions MORE said FDA was the "gold standard" and defended the booster announcement.
"That decision was made by and announced by the nation's leading public health officials," Zients said, adding that the announcement was made "to stay ahead of the virus" and to give states and pharmacies time to plan.
But he also noted the booster recommendation is pending FDA evaluation, and the Centers for Disease Control and Prevention's panel of outside experts endorsing such a recommendation.
Yet it's not clear if CDC's panel thinks the evidence is strong enough to warrant a recommendation.
While some studies have found some waning of effectiveness against infection, members of the panel said during a meeting Monday that the evidence is not clear enough to justify a booster recommendation.
Instead, they indicated any recommendation would likely consider a risk-based approach that would prioritize residents of long-term care facilities and health workers, rather than all eligible Americans at once.
Updated at 6:20 p.m.