Dr. Heidi Overton, President Trump’s nominee to lead the US Food and Drug Administration, faced pointed Senate questioning Thursday over vaccines, medication abortion, agency reform and tobacco regulation. Her answers revealed clear support for vaccines but left senators pressing for firmer commitments on other contentious issues.

Appearing before the Senate Health, Education, Labor and Pensions Committee, Overton broke with Trump’s claims about the MMR vaccine. She called the vaccine “not lethal” and described it as safe, effective and “our best tool right now in the public health response to the measles outbreak.”

Sen. Bill Cassidy asked whether any vaccines currently available in the United States were unsafe. “Every vaccine on the US market right now are safe and effective, according to the FDA,” Overton replied.

Cassidy also asked how she would respond if Trump directed her to act against scientific evidence. Overton said she would offer her best advice and follow statutory requirements governing FDA commissioners when making individual product decisions about safety and effectiveness.

Overton currently serves as deputy assistant for domestic policy and has overseen White House health initiatives during Trump’s second administration. She previously joined Trump’s first administration as a White House fellow on the Domestic Policy Council during the Covid-19 pandemic.

A physician, Overton graduated from the University of New Mexico School of Medicine and was a surgical resident at Johns Hopkins University, according to her LinkedIn profile. She is certified by a medical board in public health and general preventive medicine and, at 37, would be among the youngest people ever to lead the FDA.

Overton later completed a Ph.D. in clinical investigation at the Johns Hopkins Bloomberg School of Public Health. She also served as chief policy officer at the America First Policy Institute, a group described as a pro Trump think tank.

During her opening statement, Overton disclosed that she was diagnosed as an adult with type 1 diabetes. The autoimmune condition occurs when the body attacks insulin producing cells in the pancreas, and promising cell therapies are being developed to treat and potentially reverse it.

Progress involving cell and gene therapies has been hindered by an FDA backlog in recent years. If confirmed, Overton would be positioned to streamline the process for biotechnology companies developing new therapies.

She would also inherit an agency under substantial strain. The FDA employs about 16,000 people, operates with a roughly $7 billion annual budget and has lost about 4,600 workers since 2024 through Trump administration staffing cuts, according to Office of Personnel Management data.

Cassidy has questioned whether Overton possesses enough managerial experience to oversee such a large organization. Former FDA official Dr. Peter Lurie, now president of the nonprofit Center for Science in the Public Interest, said the agency has lost thousands of employees and is struggling with food recalls and outbreaks of foodborne illness.

“This is no time for a commissioner who needs on-the-job training,” Lurie said in a statement. Trump, by contrast, has strongly praised Overton, calling her a “ROCKSTAR” who takes on difficult issues and delivers solutions.

Medication abortion became another major pressure point during the hearing. The FDA regulates mifepristone, one of two medications used to induce abortions, and the drug remains the subject of ongoing litigation and an internal agency safety review.

Overton previously celebrated the Supreme Court’s June 2022 decision overturning Roe v. Wade as a “huge victory for life.” She also wrote a policy brief calling medication abortions “dangerous to women,” despite evidence cited by the American College of Obstetricians and Gynecologists that the medications are safe and effective.

Sen. Patty Murray called Overton a “far-right, anti-abortion extremist” and said she would oppose the nomination. When Sen. Tammy Baldwin asked whether mifepristone’s label or approval conditions should change, Overton said she could not prejudge the ongoing safety review.

Baldwin urged Overton to follow the established evidence concerning mifepristone’s safety and effectiveness. Sen. Lisa Murkowski separately raised concerns that restoring requirements for in person dispensing could restrict access for women in Alaska, where obtaining care can already be challenging.

Overton also declined to answer directly when repeatedly asked whether she would disagree with Trump or tell him when he was wrong. Sen. Maggie Hassan responded that Americans need an FDA leader capable of telling the president when he is wrong.

The committee’s members will decide whether to advance Overton’s nomination to the full Senate. If confirmed, she would succeed Dr. Marty Makary, who resigned in May amid intense pressure, and take control of an agency confronting staffing, morale and regulatory challenges.