More than 15,000 doctors have signed a letter urging senators to vote against confirming Robert F. Kennedy Jr., President-elect Donald Trump’s pick for secretary of health and human services.

“The health and well-being of 336 million Americans depend on leadership at HHS that prioritizes science, evidence-based medicine, and strengthening the integrity of our public health system,” the letter reads. “RFK Jr. is not only unqualified to lead this essential agency — he is actively dangerous.”

The letter was posted online by the Committee to Protect Health Care, a physicians advocacy group. Beyond his well-documented anti-vaccine views and advocacy, the letter cites other conspiracy theories Kennedy has actively spread, including baseless claims about a link between school shootings and antidepressants and his promotion of disproven treatments for Covid-19.

“This appointment is a slap in the face to every health care professional who has spent their lives working to protect patients from preventable illness and death,” the letter says.