Authorized for FDA Emergency Use only

(casirivimab and imdevimab)

Authorized Use

REGEN-COV (casirivimab and imdevimab) is an investigational medicine used to treat mild to moderate symptoms of COVID-19 in non-hospitalized adults and adolescents (12 years of age and older who weigh at least 88 pounds [40 kg]), and who are at high risk for developing severe COVID-19 symptoms or the need for hospitalization. REGEN-COV is investigational because it is still being studied. There is limited information known about the safety and effectiveness of using REGEN-COV to treat people with COVID-19.

  • REGEN-COV has not been approved, but has been authorized for emergency use by FDA
  • This use is authorized only for the duration of the declaration that circumstances exist justifying the authorization of the emergency use under section 564(b)(1) of the Act, 21 U.S.C. § 360bbb-3(b)(1), unless the authorization is terminated or revoked sooner

Important Safety Information

Warnings and important possible side effects of REGEN-COV (casirivimab and imdevimab)

  • Allergic reactions: Allergic reactions can happen during and after infusion with REGEN-COV. Tell your healthcare provider right away if you get any of the following signs and symptoms of allergic reactions: fever, chills, nausea, headache, shortness of breath, low or high blood pressure, rapid or slow heart rate, chest discomfort or pain, weakness, confusion, feeling tired, wheezing, swelling of your lips, face, or throat, rash including hives, itching, muscle aches, feeling faint, dizziness and sweating. These reactions may be severe or life threatening.
  • Worsening symptoms after treatment: You may experience new or worsening symptoms after infusion, including fever, difficulty breathing, rapid or slow heart rate, tiredness, weakness or confusion. If these occur, contact your healthcare provider or seek immediate medical attention as some of these events have required hospitalization. It is unknown if these events are related to treatment or are due to the progression of COVID-19.

The side effects of getting any medicine by vein may include brief pain, bleeding, bruising of the skin, soreness, swelling, and possible infection at the infusion site. The side effects of getting any medicine by subcutaneous injection may include pain, bruising of the skin, soreness, swelling, and possible infection at the injection site.

These are not all the possible side effects of REGEN-COV. Not a lot of people have been given REGEN-COV. Serious and unexpected side effects may happen. REGEN-COV is still being studied, so it is possible that all of the risks are not known at this time.

It is possible that REGEN-COV could interfere with your body’s own ability to fight off a future infection of SARS-CoV-2. Similarly, REGEN-COV may reduce your body’s immune response to a vaccine for SARS-CoV-2. Specific studies have not been conducted to address these possible risks. Talk to your healthcare provider if you have any questions.

Pregnancy and breastfeeding

There is limited experience treating pregnant women or breastfeeding mothers with REGEN-COV. For a mother and unborn baby, the benefit of receiving REGEN-COV may be greater than the risk from the treatment. If you are pregnant or breastfeeding, discuss your options and specific situation with your healthcare provider.

Tell your healthcare provider about all of your medical conditions, including if you:

  • Have any allergies
  • Are pregnant or plan to become pregnant
  • Are breastfeeding or plan to breastfeed
  • Have any serious illnesses
  • Are taking any medications (prescriptions, over-the-counter drugs, vitamins, and herbal products)

Receiving REGEN-COV (casirivimab and imdevimab)

REGEN-COV consists of two investigational medicines, casirivimab and imdevimab, given together as a single intravenous infusion (through a vein). You will receive one dose of REGEN-COV by intravenous infusion. The infusion will take 20 to 50 minutes or longer. Your healthcare provider will determine the duration of your infusion.

If your healthcare provider determines that you are unable to receive REGEN-COV as an intravenous infusion which would lead to a delay in treatment, then as an alternative, REGEN-COV can be given together in the form of subcutaneous injection (medicine is injected in the tissue just under the skin). One dose will consist of 4 subcutaneous injections given in separate locations around the same time.

Please see the Fact Sheet for Patients, Parents and Caregivers for more information.

The product information in this site is intended only for residents of the U.S. The products discussed herein may have different product labeling in different countries.

You are encouraged to report negative side effects of prescription drugs to the FDA Visit or call 1-800-FDA-1088.

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