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Warning of “serious side effects” of two antimalarial drugs, a U.S. agency has taken back their authorization to be used on COVID-19 patients.

AP Photo/John Locher

FDA just gave a thumbs down to Trump’s favorite COVID-19 drugs

Sciences COVID-19 reporting is supported by the Pulitzer Center.

The U.S. Food and Drug Administration (FDA) today revoked its emergency use authorization (EUA) for hydroxychloroquine sulfate (HCQ) and chloroquine phosphate (CQ) to treat COVID-19. The two antimalaria drugs, touted by President Donald Trump and others as potential game-changers in tackling the new coronavirus that causes COVID-19, have failed in recent randomized controlled clinical trials to prevent disease in newly infected people or treat those with symptoms. In April, former FDA leaders decried the agency’s decision to authorize emergency use of the drugs, asserting it was based on political pressure, not scientific evidence.

“I’m glad to see FDA remediate an action that was a significant departure from its science-based approach. I hope this is a step forward to FDA regaining its independence and for making decisions that are based on science and the public interest,” says Luciana Borio, a former FDA acting chief scientist who directed medical and biodefense preparedness for Trump’s National Security Council.

Citing its ongoing scientific review, the agency said in a statement: “FDA has determined that CQ and HCQ are unlikely to be effective in treating COVID-19 for the authorized uses in the EUA. Additionally, in light of ongoing serious cardiac adverse events and other serious side effects, the known and potential benefits of CQ and HCQ no longer outweigh the known and potential risks for the authorized use.”

The EUA was not a formal approval of the drugs by the agency but primarily allowed their distribution from a national stockpile to hospitals for use with COVID-19 patients. According to further information provided by FDA, the revocation does not mean the drugs can no longer be used in clinical trials, although physicians and scientists are already debating whether to continue any ongoing trials. (The World Health Organization said today at a briefing it would provide an update tomorrow on whether it will continue the HCQ arm of its Solidarity trial.) Physicians can still use the two drugs “off label,” meaning they can be given to treat conditions that were not part of the FDA approval process, although the agency’s warning about side effects is now likely to discourage many physicians from doing that.

With reporting by Charles Piller and Kai Kupferschmidt.