Dr. Jay Bhattacharya, a Stanford College well being economist who got here to prominence crusading in opposition to lockdowns in the course of the coronavirus pandemic, confronted questioning from the Senate well being committee on Wednesday morning as President Trump’s nominee to direct the Nationwide Institutes of Well being.

The company, the world’s largest funder of biomedical analysis, with a $48 billion finances and 27 separate institutes and facilities, has been rocked currently by the Trump administration’s efforts to block authorities spending and shrink the federal work pressure. Hours earlier than Wednesday’s listening to, the Division of Authorities Effectivity, the cost-cutting group led by Elon Musk, trumpeted the cancellation of N.I.H. grants.

Dr. Bhattacharya, who has a medical diploma and is a professor of drugs however has by no means practiced, has expressed an curiosity in restructuring the company and decreasing the ability of “scientific bureaucrats” who he has stated find yourself “dominating a area for a really very long time.”

His views on medication and public well being have at instances put Dr. Bhattacharya at odds with most of the scientists whose analysis the N.I.H. oversees.

Whereas he has defended vaccines and has stated he was doubtful that they precipitated autism, Dr. Bhattacharya instructed an interviewer final yr that he couldn’t rule out a hyperlink. “I don’t know that for a reality,” he stated. Intensive proof reveals no hyperlink between immunizations and autism.

Dr. Bhattacharya grew to become a go-to witness in court docket instances difficult Covid insurance policies, together with masks mandates. In a number of instances, judges stated he was disregarding details or was untrustworthy. His detractors word that whereas he has revealed research on well being coverage points — like drug costs and the hyperlink between various kinds of medical insurance and H.I.V. deaths — he’s not a scientist conducting biomedical analysis, the core mission of the company.

However supporters have stated that Dr. Bhattacharya might convey wanted reform to the N.I.H. and have defended a few of his contrarian views on Covid.

Dr. Bhattacharya burst into the information on the top of the pandemic in October 2020, when he co-wrote an anti-lockdown treatise, the Nice Barrington Declaration, that argued for “centered safety” — a method that will concentrate on defending the aged and weak whereas letting the virus unfold amongst youthful, more healthy folks.

The nation’s medical management, together with Dr. Francis S. Collins and Dr. Anthony S. Fauci, then director of the Nationwide Institute of Allergy and Infectious Illnesses, denounced the plan. Referring to Dr. Bhattacharya and his co-authors as “fringe epidemiologists,” Dr. Collins wrote in an e-mail that “there must be a fast and devastating takedown of its premises.”

Dr. Collins, who later stepped down because the N.I.H. director to pursue his laboratory analysis, retired final week in anticipation of Dr. Bhattacharya’s arrival.