As yet, there is only anecdotal evidence that hydroxychloroquine and chloroquine can help in the treatment of infection with the novel coronavirus.

However, demand has increased rapidly after President Trump suggested that it could potentially be used as a treatment for COVID-19. The drug is currently used to prevent or treat malaria infection, it is also used to treat rheumatoid arthritis and lupus.

According to the US Center for Disease Control and Prevention​ (CDC), both forms of the drug have shown in-vitro​ activity against various forms of coronavirus, with a further study in China reporting that chloroquine treatment of COVID-19 patients displayed clinical and virologic benefit against a comparison group.

As a result, Novartis, Teva, and Bayer all announced that they would be donating doses numbering in the millions globally. While Mylan, another producer, noted that it would take steps to scale up its manufacturing capacity.

In terms of numbers, Novartis will donate 130 million doses, Teva will donate 16 million over the month, and Bayer three million.

For its part, Mylan announced that it has restarted production of hydroxychloroquine sulfate tablets at its West Virginia, US facility, and that it will also take steps to begin manufacture of the product outside of the US in the coming weeks.

The US Food and Drug Administration (FDA) is not currently recommending the drug for use as a treatment, as the therapeutic potential against COVID-19 is still being evaluated by government agencies and academic centers.

Stephen Hahn, FDA commissioner, outlined that the agency is aware that there may be additional pressures on supply of the product: “We will engage with domestic manufacturers to ramp up production of this product to mitigate any potential supply chain pressures. If clinical data suggests this product may be promising in treating COVID-19, we know there will be increased demand for it.​

“We will take all steps to ensure chloroquine remains available for patients who take it to treat severe and life-threatening illnesses such as lupus.”​