YouTube
/FDA
George Tidmarsh, who helmed the FDA’s Center for Drug Evaluation and Research, resigned Sunday following a complaint by biopharma investor Kevin Tang, whose affiliated company, Aurinia Pharmaceuticals, filed a lawsuit against the former regulator on Sunday.
George Tidmarsh, director of the FDA’s Center for Drug Evaluation and Research, resigned from his post Sunday amid an ongoing probe over his “personal conduct,” according to
several
media
reports
.
Tidmarsh was placed on administrative leave on Friday, a spokesperson for the Health Department told
CNBC
, after the agency was made aware of “serious concerns about his personal conduct.” Tidmarsh tendered his resignation Sunday morning, effective immediately.
Tidmarsh was
appointed
in July, bringing with him years of industry experience. He had held several executive spots at different companies, including Solano Therapeutics, La Jolla Pharmaceutical and Horizon Pharma.
The investigation that ultimately led to Tidmarsh’s resignation is connected to a complaint by Kevin Tang, who has gained a reputation in the industry because of his work
snapping up and closing down
struggling companies. Tang carries this out through his shell company Concentra Biosciences, which just this year has successfully bought at least three biotechs—
iTeos
,
Cargo Therapeutics
and
Kronos Bio
—and made a pass at a few more.
Mergers & acquisitions
Tang Capital’s Concentra on Buyout Binge With Plenty of Biotech Fodder
After a slow 2024, the biotech shell company Concentra Biosciences is back, offering to buy four biotechs in the past month and seven so far this year.
August 13, 2025
·
4 min read
·
Annalee Armstrong
Read Now
In late September, Tidmarsh attracted Tang’s ire after he
singled out
Aurinia Pharmaceuticals’ lupus nephritis drug Lupkynis, which the former regulator claimed was an example of the need to reevaluate the use of approvals based on surrogate endpoints. In a now-deleted LinkedIn post, Tidmarsh said that Lupkynis had “significant toxicity” and “has not been shown to provide a direct clinical benefit for patients.” Tang is the
chair
of Aurinia’s board of directors.
“For some diseases such as lupus nephritis companies have not run trials to demonstrate the benefit on hard clinical endpoints,” Tidmarsh wrote. The FDA
signed off
on Lupkynis in 2021 based on urinary protein-creatinine ratio, a biomarker indicative of kidney health. Aurinia subsequently filed data from an extension study, which
led to a label update
for Lupkynis, reflecting better long-term efficacy.
Following Tidmarsh’s post, Tang filed a complaint with the FDA, which the agency referred to the Office of Inspector General, according to reporting from
STAT News
.
Aurinia filed a lawsuit on Sunday, accusing Tidmarsh of a “longstanding personal vendetta against Kevin Tang,”
STAT
reported.
“Secretary Kennedy expects the highest ethical standards from all individuals serving under his leadership and remains committed to full transparency,” a health department spokesperson told
STAT
in a statement on Sunday.
Tidmarsh’s tenure at the FDA was rocky. In an article on Sunday,
The New York Times
reported that Tidmarsh found the agency to be a toxic work environment—a situation that he attributed to Vinay Prasad, his counterpart at the Center for Biologics Evaluation and Research. Prasad himself was
kicked
out of the FDA in late July, before being
reinstated
10 days later.
Speaking to
STAT
, Tidmarsh suggested that Prasad had a role to play in his ouster, though he did not provide additional details.
Tidmarsh’s resignation continues a string of high-pro at the Department of Health and Human Services. Most prominently, CDC Director Susan Monarez was
given the boot
after just 28 days on the job—a termination she alleges was driven by her refusal to pre-approve vaccine recommendations. Earlier this year, Prasad’s predecessor
Peter Marks
and
Nicole Verdun
, former director of the FDA’s Office of Therapeutic Products, also left the agency.