Trump given remdesivir to fight his COVID-19 infection. Here's what you need to know about it

President Donald Trump's doctors are already employing one of the most prominent experimental drugs in the fight against the coronavirus to help shorten his illness.

The president's physician, Navy Cmdr. Sean Conley, said in an update on Trump's condition that therapy had begun with the drug remdesivir, which has been authorized for COVID-19 patients by the Food and Drug Administration under an emergency use declaration. Trials showed effectiveness under some circumstances.

"He has completed his first dose and is resting comfortably," Conley wrote of Trump in the update released through the White House. As a precaution, Trump was flown Friday to Walter Reed Military Medical Center near Washington after testing positive for COVID-19

Unlike hydroxychloroquine, a drug touted by Trump earlier in the pandemic as a possible treatment early in the pandemic, remdesivir has been less controversial.

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It received a guarded endorsement from Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health, when it was announced as a new tool in the fight against the virus at the president's press conference on April 29.

Fauci called it "a very important proof of concept" based on study results, although not a "knock out." Trump said, "it's a very positive event.”

The study of 400 hospital patients found 74% who received remdesivir had gotten better after 14 days compared to 59% who did not receive it. Some 8% of the patients treated with remdesivir had died by the end of their second week in the hospital, slightly better than the 12% who had gone without it.

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But race could make a difference in the results, the company's data shows. Some 84% of Black patients showed improvement at the end of two weeks of hospitalization, compared to 76% of Latino patients, 67% for both Asian Americans and non-Hispanic whites.

Two months after remdesivir was approved for COVID-19 treatment, the Health and Human Services Department said it had secured 500,000 treatment courses of remdesivir and had plans to gradually increase its availability through September. A course is 6.25 vials.

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“President Trump has struck an amazing deal to ensure Americans have access to the first authorized therapeutic for COVID-19,” said HHS Secretary Alex Azar said in a statement. “To the extent possible, we want to ensure that any American patient who needs remdesivir can get it.

Remdesivir, which also goes by the brand name Veklury, is made by Gilead Science, based in Foster City, California.