The US is sitting on a pile of 66 million anti- malaria pills after they were scrapped as a treatment for COVID-19 by the Food and Drug Administration (FDA).

The FDA approved chloroquine and hydroxychloroquine for use on hospitalized COVID-19 patients on March 28 but revoked it on Monday, less than three months later, following debate over their efficacy and safety.

The drugs "are unlikely to be effective in treating COVID-19" and can result in "serious" heart-related side effects, the FDA said.

As of Monday, the US government had distributed 31 million hydroxychloroquine tablets from the Strategic National Stockpile to state health agencies, a Health and Human Services (HHS) spokesperson told The New York Times.

Sixty-three million hydroxychloroquine tablets remain in federal storage.

Additionally, none of the 3 million doses of chloroquine gifted to the US by the German pharma giant Bayer in March were ever distributed, The Times reported.

It is not yet known what will become of the federal stockpile.

Officials are working with the drug donors to "determine the available options" for the excess pills, a HHS spokesperson told The Times.

Dr Rick Bright, the former head of the US Biomedical Advanced Research and Development Authority (BARDA), tweeted on Monday that the drugs "should never have been brought into our country and should be destroyed."

Hydroxychloroquine is still approved for use to treat malaria by the FDA, but it is unlikely that the US population will require as many as 66 million pills.

Trump, who took hydroxychloroquine for two weeks, did not approve of the FDA's decision to revoke the emergency waiver, saying on Monday it "certainly didn't hurt me."

Peter Navarro, Trump's trade adviser, told The Times on Monday that the FDA U-turn was "a Deep State blindside by bureaucrats who hate the administration they work for."

In May, France banned the use of hydroxychloroquine to treat COVID-19, while the UK was seeking out 16 million pills in case it turns out to be a successful treatment.

This article was originally published by Business Insider.

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