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Answers to providers’ common questions about monoclonal antibody (mAb) treatment.

Three mAbs have received Emergency Use Authorization (EUA) from the U.S. Food and Drug Administration (FDA) for patients with mild to moderate COVID-19 who have a high risk of developing complications and becoming seriously ill. In early studies, mAbs have been effective in decreasing the risk of hospitalization for high-risk patients.

These treatments have received EUA from FDA based on the treatments’ potential to reduce high-risk patients’ need for hospitalization. The safety and effectiveness of these treatments continue to be evaluated.

Studies indicate that mAb treatments must be given within 10 days of the onset of symptoms.

Three mAb treatments have received EUA from the FDA: bamlanivimab, the combination of casirivimab and imdevimab, and the combination of bamlanivimab and etesevimab. All are administered via intravenous (IV) infusion.

The three treatments are designed in a very similar way, with the same goal: to bind to a specific place on the spike protein on the SARS-CoV-2 virus and prevent it from attaching to and entering human cells.

The treatments are offered at more than 5,000 infusion locations across the United States. These include hospitals, infusion centers, urgent care clinics, and emergency departments.

Because infusion locations have received varying amounts of mAb treatments, not all locations may be accepting new patients. Before sending their patients to the nearest infusion center, healthcare providers should contact the infusion center to ensure treatments are still available. (See “How do I make a referral for mAb treatment?” below.)

Patients who may qualify for mAb treatment:

a) Have a positive test confirming an infection with the SARS-CoV-2 virus, and

b) Have had mild to moderate symptoms of COVID-19 for 10 days or less, and

c) Meet the FDA’s criteria for high risk of developing more severe symptoms.

For details, visit How Do I Know If I’m High Risk, and What Do I Do Next? on this website.

Possible side effects of bamlanivimab include anaphylaxis (rarely) and infusion-related reactions including nausea, diarrhea, dizziness, headache, itching, and vomiting.

Possible side effects of casirivimab and imdevimab include anaphylaxis (rarely) and infusion-related reactions including fever, chills, hives, itching, and flushing.

Most infusion reactions with mAbs are mild and can be (a) managed by slowing the infusion rate or (b) treated with an antihistamine. However, mAbs may only be administered in settings in which healthcare providers have immediate access to medications to treat a severe infusion reaction, such as anaphylaxis, and the ability to activate the emergency medical system, as necessary.

Challenges for providers include: identifying patients in time for them to receive mAb treatment (within 10 days of the onset of symptoms), devoting time to educating patients about these treatments, and referring them to an infusion center.

Challenges for healthcare systems include: the need to set up a dedicated space for IV infusions, taking measures to control infection for COVID-19 patients, and dedicating staff to administer the treatments and monitor mAb patients.

Challenges for patients include possible financial costs. The federal government pays for the mAb treatments, but hospitals may charge for administering the treatments (Medicare covers these costs).

Depending on the product, the entire treatment process typically takes 2 to 4 hours.

a) Review the available infusion locations in your area. Contact the infusion location(s) to learn their required referral procedures and whether they are accepting new patients.

b) Discuss with your qualifying patients that they are at high risk for developing serious symptoms of COVID-19. You also could show them the U.S. Department of Health and Human Services flyer (PDF) about mAb treatments available on the Combat COVID website.

c) Tell your qualifying patients what the treatment process will generally involve, and refer them to the infusion location nearest them that is accepting new patients.

d) If you’re having difficulty locating an infusion site in your area, contact [email protected] for assistance.