Two of the top vaccine regulators at the Food and Drug Administration are leaving this fall, reportedly because they’re upset that the Biden Administration is pressuring the agency to approve COVID-19 booster shots to American adults .

The New York Times reports that an inter-agency email revealed that Dr. Marion Gruber, the director of the F.D.A.’s vaccines office, will retire at the end of October, and her deputy, Dr. Philip Krause, will exit in November.

Sources indicated both women were upset the White House jumped the gun with its declaration that booster shots should be given eight months after people have received their second vaccine dose. Neither reportedly believes there is enough solid data to justify giving booster shots at the moment.

More from the Times:

Some public health experts have said the administration’s booster shot announcement, which did include a caveat that the F.D.A. would first have to authorize such shots, undermined the agency’s responsibility to make that assessment on its own schedule, led by career scientists. Since Mr. Biden took office in January, the White House has made a point of saying it would not influence the F.D.A.’s work.
Some outside experts have also challenged the booster plan as premature, saying the available data shows that the Pfizer-BioNTech and Moderna vaccines are holding up well against severe disease and hospitalization, including against the Delta variant. Extra shots would be warranted only if the vaccines failed to meet that standard, some have said.

Politico is also reporting that some within the FDA think the agency is being compromised by political pressure as it was during the Trump Administration.

The plan remains to have eligible Americans start receiving boosters next month. The White House insists the strategy was endorsed by senior federal health officials including acting F.D.A. commissioner Dr. Janet Woodcock. Officials in the Biden Administration say the increased urgency is not politically motivated, but a necessary step because of mounting evidence that suggests the vaccines lose potency over time to protect against severe reactions and hospitalizations.

There is also worry within the agency that the departures of Doctors Gruber and Krause will complicate the FDA’s work on deciding whether to recommend coronavirus vaccines for children under 12.