The Food and Drug Administration is likely to come under tighter scrutiny over vaccine development and safety testing once Donald Trump takes over as the country’s president, a top official at the agency said on Thursday.

Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, said at an industry conference that the agency could be asked to be more transparent and meet more often with outside advisers to discuss vaccines.

“I don’t necessarily view that as a bad thing,” he said at the conference hosted by brokerage Jefferies. “That may turn out to be an opportunity to have an open dialogue.”

Marks said the FDA could also shift its messaging on vaccines by emphasizing that the benefits of taking them outweigh the risks.

He said that outside of vaccines, he does not expect major changes in regulations of other biological drugs, including gene and cell therapies.

Industry insiders, biotech investors and Wall Street analysts are worried about potential regulatory changes for vaccines after Trump nominated Robert F. Kennedy Jr., an environmental activist who has spread misinformation on vaccines, to lead the Department of Health and Human Services.

The FDA and other health agencies like the Centers for Disease Control and Prevention fall under the purview of the HHS.

Shares of U.S. pharmaceutical companies, especially vaccine makers, fell on Friday on concerns over the changes Kennedy could make at the FDA, an agency he has accused of doing the bidding of Big Pharma and Big Food. His team has also said there would be a vetting process to find FDA employees with ties to the industry.

“There are things that could happen that could adversely affect the workforce,” said Marks, adding that “it may get difficult to hire until a lot of the dust has settled”.