The Food and Drug Administration said it is ending its emergency use authorization for chloroquine and hydroxychloroquine, the anti-malaria drugs backed by President Donald Trump to combat Covid-19.

The agency determined the drugs were “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 FDA wrote in its notice.

The FDA issued the emergency use authorization for the drugs in March. The EUA meant that doctors would be allowed to use the drugs on patients hospitalized with Covid-19 even though they had not been formally approved by the agency.

However, the agency warned consumers a month later against taking the drugs to treat Covid-19 outside a hospital or formal clinical trial setting due to the risk of “serious heart rhythm problems” in some patients.