The US Food and Drug Administration (FDA) on Monday revoked the Emergency Use Authorization (EUA) that allowed for chloroquine phosphate (CQ) and hydroxychloroquine sulfate (HCQ) to be used to treat certain hospitalized patients with COVID-19.

Under § 564 of the federal Food, Drug, and Cosmetic Act, the authorization of a product for emergency use may be revised or revoked when the criteria under section 564(c) of the Act for issuance of such authorization are no longer met. Under section 564(c)(2) of the Act, an EUA may be issued only if FDA concludes “it is reasonable to believe that: (A) the product may be effective in diagnosing, treating, or preventing—(i) such disease or condition…; and (B) the known and potential benefits of the product, when used to diagnose, prevent, or treat such disease or condition, outweigh the known and potential risks of the product.”

The FDA determined that oral formulations of HCQ and CQ are unlikely to be effective in treating COVID-19, nor is it reasonable to believe that the known and potential benefits of these products outweigh their known and potential risks.

HCQ and CQ that were distributed from the Strategic National Stockpile under this EUA remain authorized for emergency use to continue to treat any hospitalized patient to whom the authorized product has already been administered during the COVID-19 public health emergency, to the extent found necessary by such patient’s attending physician.

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