Kennedy has been criticized for making false medical claims. He has also vowed to purge the U.S. Food and Drug Administration.

President-elect Donald Trump said he’s tapping Robert F. Kennedy Jr. to run the Department of Health and Human Services, a move that would elevate a prominent vaccine skeptic and pharmaceutical industry critic to a top role on federal health policy.

Shares of major U.S. drugmakers fell on Friday after President-elect Donald Trump picked anti-vaccine activist Robert F. Kennedy Jr. to head the Department of Health and Human Services, the top U.S. health agency.