What Does Regeneron's Experimental Antibody Cocktail Do?

President Trump walking.
Drew Angerer/Staff / Getty Images

Key Takeaways

  • Early Friday morning, President Trump announced that he and First Lady Melania Trump tested positive for COVID-19.
  • President Trump received an experimental COVID-19 antibody cocktail still in clinical trials.
  • The drug is not yet approved by the U.S. Food and Drug Administration, meaning it is not yet available to the general public.

Early Friday morning, President Trump announced that he and First Lady Melania Trump tested positive for COVID-19. Later that afternoon, the President received an experimental COVID-19 drug still in clinical trials according to a White House statement. The drug, an "antibody cocktail," is manufactured by biotechnology company Regeneron

President Trump has since been taken to the Walter Reed National Military Medical Center in Bethesda, Maryland, "out of an abundance of caution, and at the recommendation of his physician and medical experts," according to press secretary Kayleigh McEnany.

Sean P. Conley, DO, FACEP, President Trump's physician, stated in the memo that the President received an 8-gram dose of polyclonal antibodies produced by Regeneron. In addition to the antibody, the President has been taking zinc, vitamin D, famotidine, melatonin, and daily aspirin.

Here's what we know about Regeneron's antibody cocktail.

What Is An Antibody Cocktail?

Polyclonal antibodies—which are being referred to as an antibody cocktail—are laboratory-produced versions of the antibodies typically used by the immune system to fight off infection. Polyclonal antibodies can restore, enhance, or mimic the immune system's form of attack.

Regeneron generates these antibodies outside of the body, derived from either genetically-humanized mice or convalescent (recovered) humans. These antibodies can be delivered via injection, providing passive immunity—short-term immunity resulting from the introduction of antibodies from another person or animal—though they must be re-administered to remain effective over time. These antibodies can also potentially treat an existing infection.

Findings Are Preliminary

On Tuesday, Regeneron announced promising results for its antibody cocktail, called REGN-COV2. In preliminary results from a trial of 275 non-hospitalized COVID-19 patients, the drug reduced viral load and the time to alleviate symptoms in non-hospitalized patients with COVID-19. But the study has yet to be peer-reviewed, and the drug has not received approval from the U.S. Food and Drug Administration (FDA).

Initial data from the study found that this treatment showed the greatest improvements in patients "who had not mounted their own effective immune response prior to treatment," according to the Regeneron press release.

A high dose (8 grams), which is the amount given to President Trump, seemed to have the greatest effect. But in the group with detectable levels of their own antibodies, even a lower dose (2.4 grams) of the Regeneron antibodies seemed to result in patients getting better faster.

For patients who did not have detectable antibodies at the study’s outset, Regeneron’s antibody cocktail improved symptoms as well. In this group, symptoms were alleviated in 13 days on placebo, eight days in the high-dose group, and six days in the low-dose group.

What This Means For You

Regeneron's antibody cocktail is still in clinical trials and not yet available to the public. But results from their initial trials are promising, and the cocktail may be available as a treatment for COVID-19 patients in the near future.

Who Can Get It?

Because the drug is not yet approved by the FDA, this treatment is not available to the general public. Regeneron was allowed to release the drug under the "Compassionate Use Request" in which the FDA permits usage to people not in clinical trials.

Certain criteria are require for this usage:

  • The disease is serious or immediately life-threatening.
  • No treatment is available or approved treatments haven't helped the condition.
  • The patient isn't eligible for clinical trials of the experimental drug.
  • A doctor agrees there are no other options and the experimental treatment may help.
  • A doctor feels the benefit justifies the potential risks of the treatment.
  • The company that makes the drug agrees to provide it.

According to The New York Times, Regeneron’s chief executive, Leonard S. Schleifer, MD, PhD, stated that this isn't the first time the treatment has been granted compassionate use by the FDA. “When it’s the president of the United States, of course, that gets—obviously—gets our attention," he said.

Regeneron plans to rapidly discuss initial clinical trial results with regulatory authorities.

The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit our coronavirus news page.

3 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Cision. PR Newswire. Regeneron Begins First Clinical Trials of Anti-Viral Antibody Cocktail REGN-COV2 for the Treatment and Prevention of COVID-19. June 11, 2020.

  2. Regeneron. Regeneron's REGN-COV2 Antibody Cocktail Reduced Viral Levels and Improved Symptoms in Non-hospitalized COVID-19 Patients. September 29, 2020.

  3. Mayo Clinic. I've Heard That Compassionate Use is a Way to Get Access to Experimental Treatments. How Does it Work? February 12, 2020.

By Paola de Varona
Paola de Varona is an associate news editor at Verywell Health who graduated with a master's degree from the Medill School of Journalism.