COVID-19 Treatments: Monoclonal Antibodies

One of the outpatient treatment options available for COVID-19 patients at Yale New Haven Health, particularly those who may be at risk for developing a more severe form of the virus but are not yet sick enough to be hospitalized, is the use of monoclonal antibodies. Just like antibodies that develop naturally in the body, monoclonal antibodies help the body fight off viruses like COVID-19. However, monoclonal antibodies are manufactured in a lab and are not derived from human blood products.

The FDA authorized the emergency use of two monoclonal antibody treatments: bamlanivimab/etesevimab or casirivimab/imdevimab. These medicines are antibodies that work against a protein needed by the virus, which causes COVID-19 to enter cells in the body. The antibodies bind to this protein, preventing the virus from infecting cells in your body.

If you or a loved one has been diagnosed with COVID-19, your primary care physician may refer you to a Yale New Haven Health facility for monoclonal antibody treatment. (Infusion centers are available at Bridgeport Hospital, Greenwich Hospital, Lawrence + Memorial Hospital, Westerly Hospital and Yale New Haven Hospital.) During your appointment, you will receive one dose of the medication through a vein (intravenous or IV infusion) and can return home after a brief monitoring period.

Researchers found these medicines reduced the need for hospitalization in outpatients with mild to moderate COVID-19, compared to patients who received a placebo. This kind of treatment is only available for outpatients who meet specific criteria and clinicians must request it.

To learn more about how this treatment works and for a full list of requirements, read more below.

How are these medicines administered?

Bamlanivimab/etesevimab or casirivimab/imdevimab are given to outpatients at Yale New Haven Health System locations. Patients receive one dose of bamlanivimab/etesevimab or casirivimab/imdevimab through a vein (intravenous or IV infusion). Afterwards, you will be monitored by our care team for possible side effects for another hour after the infusion has ended. Patients who receive this treatment should have someone drop them off and pick them up.

This treatment is administered at Yale New Haven Hospital, Greenwich Hospital, Bridgeport Hospital, Lawrence + Memorial Hospital and Westerly Hospital. Before getting this treatment, patients must get a referral from a physician.

Who is eligible?

Patients must be at least 12 years old, weigh at least 88 pounds, and have a documented positive result of a direct SARS CoV-2 viral test within the last 10 days. They must also meet the following clinical criteria:

Patients younger than 65 must have one of the following comorbidities:

  • Diabetes mellitus
  • BMI > 40 kg//m2
  • Chronic Kidney Disease, Stage III or higher or receiving dialysis
  • Congestive Heart Failure NYHA Class III or higher
  • Severe pulmonary disease defined as one of the following: COPD with continuous home oxygen, pulmonary hypertension/pulmonary fibrosis, or cystic fibrosis
  • Cirrhosis—Child Class B or C
  • Immunosuppressed status due to an underlying immunocompromising condition or use of immunosuppressive therapy
  • Sickle cell disease
  • Parkinson’s disease

Patients aged 12-17 with one of the following:

  • Congenital or acquired heart disease
  • Neurodevelopmental disorders
  • Medical-related technological dependence, for example, tracheostomy, gastrostomy, or positive pressure ventilation (not related to COVID-19)
  • Chronic respiratory disease excluding asthma

Of the two medicines, which one will patients receive?

Both medicines work in the same fashion and are equally effective. The supply of each medicine is limited at this time, so which one you will receive will depend on the availability of the drug at the time of infusion.

What are the possible side effects?

Possible side effects of bamlanivimab/etesevimab or casirivimab/imdevimabcan include allergic reactions, which can happen during and after infusion. Reactions are rare but can include fever, chills, nausea, headache, shortness of breath, low blood pressure, wheezing, swelling of your lips, face, or throat, rash including hives, itching, muscle aches, and dizziness. 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. These are not all the possible side effects. Serious and unexpected side effects may happen. Bamlanivimab/etesevimab or casirivimab/imdevimab are still being studied so it is possible that all of the risks are not known at this time.

What if I’m pregnant or breastfeeding?

There is limited experience treating pregnant women or breastfeeding mothers with bamlanivimab/etesevimab or casirivimab/imdevimab. For a mother and unborn baby, the benefit of receiving bamlanivimab/etesevimab or casirivimab/imdevimab may be greater than the risk from the treatment. We advise our patients to discuss any possible treatment with their obstetrician or midwife.

What are the recommendations for receiving these medicines and the COVID-19 vaccine?

The COVID-19 vaccine should be deferred for at least 90 days for anyone who received this antibody therapy.

Learn more about the COVID-19 vaccine.

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The Recovery Program at the Winchester Chest Clinic

Some COVID-19 patients are continuing to experience respiratory symptoms long after their initial recovery from this illness. The Recovery Program at the Winchester Chest Clinic is open to those patients who have persistent respiratory symptoms. For patients who fit specific criteria, they should consult their primary care physician for a referral to the program.

Learn more about the program