DENVER (KDVR) — President Donald Trump received a dose of an experimental drug to treat COVID-19 described as an “antibody cocktail” prior to leaving the White House Friday. 

Regeneron Pharmaceuticals, Inc. announced two days before the president’s diagnosis the first data from a trial of its “investigational antibody cocktail” designed to help fight the virus. The company says the trial showed reduced time to alleviate symptoms in non-hospitalized patients with COVID-19 and also showed positive trends in reducing medical visits.

The drug from Regeneron is not yet approved by the FDA.

“The product hasn’t been discussed much. Frankly, it took a lot of people by surprise that it was administered,” Dr. James Neid said, an infectious disease physician with Medical Center of Aurora.

“I think the studies with the Regeneron product are early and its clinical efficacy to my knowledge has not been well-established,” Neid said.

The president has also received multiple doses of Remdesivir, an antiviral that Dr. Neid says is commonly used to treat hospitalized patients in Colorado.

“It directly impacts the ability of the virus to replicate,” Neid said. “Ideally, you’re dropping the amount of virus that is in somebody’s body so it doesn’t create such a severe illness.”

Neid says the experimental drug from Regeneron is not widely available and it’s unclear if the FDA will approve it for use against COVID-19 in the near future.

“There are so many proposed beneficial treatments out there. In order to decide clinically how to use them safely and develop clinical expertise, time needs to go by,” Neid said.