CHICAGO (CBS) — There is a local Chicago tie to the drug that is being administered to President Donald Trump is using to recover from COVID-19.

Remdesivir, as it is called, has gone through many clinical trials in Chicago. CBS 2’s Steven Graves on Saturday talked to a doctor at the University of Chicago Medical Center about why it might be a game-changer in President Trump’s recovery.

White House staff even said President Trump got his second dose of remdesivir on Saturday.

Dr. Kathleen Mullane was part of one of the biggest studies on remdesivir in the country, with positive results – ones she said prove the president would benefit from the drug because of his condition.

On Saturday night, in President Trump’s newest video on his recovery from COVID-19, he said he was grateful for the support and the treatments getting him through it.

“If you look at the therapeutics I’m taking right now, some of them, and others that are coming out right now that are looking like, frankly, they’re miracles,” President Trump said.

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One of those drugs is remdisivir, which aims to stop the virus from spreading – giving the immune system a chance to fight it off.

Higher-risk patients such as President Trump usually see the most benefit.

“He fits the criteria for the early criteria for the emergency use of the drug,” Mullane said.

Mullane held two studies around remdesivir and COVID-19, composed of 224 people. One trial was conducted on severely ill patients.

For the other study, with those who were moderately ill, some of the subjects were given a placebo.

In most cases, those on remdisivir only needed five days of therapy.

“We found that the number of days that people required in the hospital was fewer that those who had the placebo arm,” Mullane said.

The doctor said the experiment showed that the faster someone gets the drug, the better.

“The problem it’s only available intravenously, so it’s not an easy drug to use except in the hospital,” Mullane said.

That is because the Food and Drug Administration has only given the drug emergency use approval.

But President Trump is also getting help from another lesser-known drug – an antibody cocktail from Regeneron.

That one is still experimental, but Dr. Mullane said it is helpful.

“If I had a patient who presented to me who was ill and older and needed to be hospitalized, yes, I would certainly tell them to use both of those agents,” Dr. Mullane said.

In terms of remdesivir, the doctor said she is hopeful that her team’s findings can help get official approval by the FDA, which could make the drug more widely available.