Key TakeawaysThe FDA has authorized REGEN-COV to help prevent severe COVID-19 in high-risk people who have been exposed to the virus.The treatment can be delivered via IV infusion or injection.Only those over the age of 12 who are at least 88 pounds can use the treatment.

Key Takeaways

The FDA has authorized REGEN-COV to help prevent severe COVID-19 in high-risk people who have been exposed to the virus.The treatment can be delivered via IV infusion or injection.Only those over the age of 12 who are at least 88 pounds can use the treatment.

The Food and Drug Administration (FDA) has revised an emergency use authorization for the monoclonal antibody treatment REGEN-COV to include people at high risk for severe forms of COVID-19 who have had a known exposure to the virus.

The FDA stressed that this treatment is only to be used for those who have been exposed and are at risk for developing severe COVID-19 symptoms. It is not a substitute for the COVID-19 vaccine.

“This is something that makes sense,”John Sellick, DO, an infectious disease expert and professor of medicine at the University at Buffalo, tells Verywell. “When we have someone who is sick with COVID, if we get to them early enough and we give them monoclonal antibodies, it’s been shown to decrease bad outcomes.”

REGEN-COV was already authorized to treat mild-to-moderate COVID-19 in those 12 and up who have tested positive for SARS-CoV-2 and are at high risk for severe COVID-19.

“It’s a logical extension,” Sellick says.

What to Know about REGEN-COV

REGEN-COV uses monoclonal antibodies casirivimab and imdevimab, which are given together. Monoclonal antibodies are synthetic proteins that mimic the immune system’s ability to fight off pathogens like SARS-CoV-2, the virus that causes COVID-19.

“REGEN-COV is a combination of two engineered antibodies,” Jamie Alan, PharmD, PhD, associate professor of pharmacology and toxicology at Michigan State University, tells Verywell. “These antibodies bind to the spike protein of COVID-19, and they prevent the virus from attacking your cells and causing disease.”

There are similar medications that can be used to lower the risk of developing severe forms of COVID-19, like bamlanivimab or bamalanivimab in combination with etesevimab, Alan says.

COVID-19 Treatments: What You Need to Know

“REGEN-COV is essentially a ‘passive vaccine,'” Alan says. “With a vaccine, your body makes antibodies towards the spike protein, and your body will ‘store’ the information so that it can respond later when it sees the virus again. How long your body will ‘store’ that information is unclear. When you are exposed to COVID later after vaccination, your body will rapidly respond.”

If you’re unable to be vaccinated, REGEN-COV is a “great option” if you’re exposed to the virus, Alan says, noting that REGEN-COV will “temporarily give your body antibodies” against COVID-19. Alan explains that these antibodies do not last long, and the body does not ‘store’ the information.

“Vaccination is best, but REGEN-COV is a great tool in our fight against COVID,” Alan says.

Recent Data Suggests More People With COVID-19 Would Benefit From Monoclonal Antibodies

How It’s Administered to Patients

The FDA has very specific instructions on how REGEN-COV should be used for post-exposure preventative treatment, orprophylaxis. For dosage, patients should be given 600 milligrams of casirivimab and 600 milligrams of imdevimab together.

While an IV infusion is “strongly recommended,” the FDA says that REGEN-COV can also be given subcutaneously (under the skin) when an IV infusion isn’t feasible or would cause the patient to have a delay in treatment.

How Does REGEN-COV Work in the Body?REGEN-COV is a type of monoclonal antibody treatment that helps reduce the risk of developing severe COVID-19 after someone has been exposed to the virus. It binds to the spike protein in SARS-CoV-2, the virus that causes COVID-19, and keeps it from attacking your cells.

How Does REGEN-COV Work in the Body?

REGEN-COV is a type of monoclonal antibody treatment that helps reduce the risk of developing severe COVID-19 after someone has been exposed to the virus. It binds to the spike protein in SARS-CoV-2, the virus that causes COVID-19, and keeps it from attacking your cells.

Accessibility and Limitations of REGEN-COV

REGEN-COV isn’t authorized for everyone. It may only be used in people over the age of 12 who weigh at least 88 pounds. Potential patients also must:

Known Side Effects

There are a few potential side effects of REGEN-COV. They’re largely injection site reactions, including:

Antihistamines, hydrocortisone cream, and ice should help with the symptoms, Alan says. There were no cases of severe hypersensitivity reactions or potentially life-threatening allergic reactions.

How to Get REGEN-COV After Being Exposed to COVID-19

If you are at high risk for developing severe complications of COVID-19 and you have a known exposure, call your doctor. They should be able to discuss whether REGEN-COV is the appropriate treatment for you. The U.S. government has covered the cost of the first 1.5 million doses of REGEN-COV so those who need the treatment can get it for free.But patients or their insurance providers may have to pay some other administration fees.

What This Means For YouIf you’re at high risk for severe COVID-19, REGEN-COV can help after you’ve been exposed to the virus.

What This Means For You

If you’re at high risk for severe COVID-19, REGEN-COV can help after you’ve been exposed to the virus.

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 ourcoronavirus news page.

3 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Food and Drug Administration.FDA authorizes REGEN-COV monoclonal antibody therapy for post-exposure prophylaxis (prevention) for COVID-19. August 10, 2021.Food and Drug Administration.FDA authorizes REGEN-COV monoclonal antibody therapy for post-exposure prophylaxis (prevention) for COVID-19. August 10, 2021.Regeneron.Your guide to REGEN-COV. June, 2021.

3 Sources

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Food and Drug Administration.FDA authorizes REGEN-COV monoclonal antibody therapy for post-exposure prophylaxis (prevention) for COVID-19. August 10, 2021.Food and Drug Administration.FDA authorizes REGEN-COV monoclonal antibody therapy for post-exposure prophylaxis (prevention) for COVID-19. August 10, 2021.Regeneron.Your guide to REGEN-COV. June, 2021.

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

Food and Drug Administration.FDA authorizes REGEN-COV monoclonal antibody therapy for post-exposure prophylaxis (prevention) for COVID-19. August 10, 2021.Food and Drug Administration.FDA authorizes REGEN-COV monoclonal antibody therapy for post-exposure prophylaxis (prevention) for COVID-19. August 10, 2021.Regeneron.Your guide to REGEN-COV. June, 2021.

Food and Drug Administration.FDA authorizes REGEN-COV monoclonal antibody therapy for post-exposure prophylaxis (prevention) for COVID-19. August 10, 2021.

Regeneron.Your guide to REGEN-COV. June, 2021.

Meet Our Medical Expert Board

Share Feedback

Was this page helpful?Thanks for your feedback!What is your feedback?OtherHelpfulReport an ErrorSubmit

Was this page helpful?

Thanks for your feedback!

What is your feedback?OtherHelpfulReport an ErrorSubmit

What is your feedback?