Food and Drug Administration Commissioner Marty Makary is on “thin ice” with the White House, according to two sources familiar with discussions.

Makary, a surgical oncologist who first gained prominence critiquing the government’s handling of the COVID-19 pandemic, has been on shaky ground both inside the agency and with the White House for months.

He was the subject of a scathing Bloomberg report this week, which said his tenure has been marked by friction among staff and leadership, industry frustration and a general dysfunction in the agency responsible for regulating the nation’s pharmaceutical supply and approving new drugs.

One source familiar with internal deliberations told NOTUS that the concerns around Makary stem from an inability to effectively run the FDA. This source said Makary has not been able to “wrangle the bureaucracy and move quickly,” and has not been “responsive enough” to White House and agency concerns.

“Great guy. But not the best fit,” this source said.

A second source, a senior administration official, said there were no immediate plans for Makary’s ouster, but added that “could change, obviously” — an indication of just how precarious Makary’s standing currently is.

White House spokesperson Kush Desai said Makary “continues to be an invaluable asset for the Trump administration.”

Makary was initially seen as a more traditional pick to lead the FDA. Earlier in his tenure he enjoyed a close relationship with Health Secretary Robert F. Kennedy Jr., Centers for Medicare and Medicaid Services Administrator Mehmet Oz and Jay Bhattacharya, director of the National Institutes of Health.

However, Makary’s tenure has been marked by several high-profile dramas around drug approvals. In one case, the FDA shocked the pharmaceutical industry after initially declining to review Moderna’s application for an mRNA-based flu vaccine and then abruptly reversing course.

Outcry from the industry — and from some lawmakers — resulted in some of those decisions being reversed. A top FDA vaccine official, Vinay Prasad, departed the FDA last week.

In an interview with CNBC Tuesday, Makary defended the review teams at the FDA.

“I think that article in The Wall Street Journal is the ninth article they’ve posted in that opinion section, begging for Replimune’s approval,” Makary told the outlet, referring to a column in the Wall Street Journal column that accused the FDA chief of causing headaches for the administration. The column highlighted the agency rejecting a melanoma treatment from Massachusetts-based drugmaker Replimune.

“I don’t work for Replimune, I work for the American people, and I stand by the scientists at the FDA,” he said.

HHS did not respond to NOTUS’ request for comment.

The White House and Makary have also reportedly clashed over vapes. The administration has been pushing to allow more flavored e-cigarettes on the market, but Makary’s office blocked the authorization of several flavors after FDA regulators had approved them, The Wall Street Journal reported last month.

Makary has attempted to speed up the drug approval process and development of treatment for rare diseases by introducing AI tools to a traditionalist agency. He’s also pushed for a new approval process that would loosen clinical trial requirements for some medicines.

Last week, the agency announced it was piloting “real time clinical trials,” a drug testing model that uses AI to send the FDA data as a drug is tested in patients, potentially reducing the amount of time it takes for the agency to approve a new drug.

Makary, who is also an author, came to the FDA after building a reputation as a dissenting voice on how the government approached some parts of the COVID-19 pandemic. He supported some measures, like vaccines for adults, but questioned others, like booster shots for children.