The US Food and Drug Administration (FDA) announced today that it has revoked the emergency use authorization (EUA) that it had previously granted for the antimalarial drugs hydroxychloroquine and chloroquine for the treatment of COVID-19, saying that the drugs no longer met the statutory criteria for emergency use.The agency said on its website that, based on its review of the scientific evidence available for the drugs, hydroxychloroquine and chloroquine "are unlikely to be effective in treating COVID-19 for the authorized uses in the EUA." The FDA also said that because of the serious cardiac events and other side effects associated with the two drugs, the potential benefits no longer outweigh the risks.The FDA made the decision in