FDA intends to put its most serious warning on Covid vaccines, sources say

(CNN) — The US Food and Drug Administration intends to put a “black box” warning on Covid-19 vaccines, according to two people familiar with the agency’s plans, the latest move by President Donald Trump’s health officials to undermine a vaccine that was a standout victory of his first term.

The plan shocked outside experts, who said there was no basis for the warning.

A boxed warning, which appears at the top of prescribing information for medicines, is the agency’s most serious, designed to warn about risks such as death or life-threatening or disabling reactions that should be weighed against the intervention’s benefits. They can also be used when a risk might be lowered by using a medicine in a targeted way, such as only in certain groups.

Boxed warnings on opioids, for example, warn about risks of abuse, addiction, overdose and death. The acne medication Accutane carried a warning about the risks of birth defects when used during pregnancy. ACAM2000, a smallpox and mpox vaccine, has a warning about complications such as heart inflammation and encephalitis.

The plan to install the warnings for Covid-19 vaccines is being orchestrated by Dr. Vinay Prasad, the FDA’s chief medical and sci...