Does Monoclonal Antibody Treatment For COVID-19 Benefit Individuals Who Are Pregnant Or Breastfeeding?

James Hill, MD, Maternal Fetal Medicine Specialist, CHRISTUS Children’s

When the COVID-19 pandemic first emerged, there was no specific treatment for it. Fast forward a year and a half later, not only do we have safe and effective vaccines but also monoclonal antibodies for patients who develop mild to moderate coronavirus infections.

As the delta variant continues to circulate, we are hearing increasingly more about these monoclonal antibodies. But what are they, and who can benefit?

The monoclonal antibody is a Y-shaped protein that can protect the body from foreign invaders.

An antibody is a Y-shaped protein that serves like a lock-and-key to protect the body from foreign invaders, like the virus that causes COVID-19. Monoclonal antibodies are just like the ones you already have, except they are produced in a laboratory and are specifically designed to help your immune system detect and respond more effectively to the notorious spike protein of the coronavirus.

Data suggests that the sooner the monoclonal antibody treatment is given to individuals who test positive for COVID-19 and fall into specific high-risk categories, the better they may benefit by preventing progression of disease that would otherwise result in hospitalization. These high-risk groups include individuals who are overweight (body mass index over 30), diabetic, have high blood pressure, and/or cardiovascular/kidney disease.

Dr. James Hill points to evidence-based research that supports monoclonal antibody therapy for COVID positive pregnant women.

In July, the American College of Obstetricians and Gynecologists (ACOG) stated that doctors could consider monoclonal antibodies in non-hospitalized pregnant patients who fell into one of the above-mentioned high-risk groups. As recently reported by the Society of Maternal Medicine (SMFM), this guidance now applies to women who’ve recently given birth and are currently breastfeeding.  

The use of monoclonal antibodies, specifically REGEN-COV (casirivimab and imdevimab), has been used primarily on non-pregnant/non-lactating women until now; however, there is evidence to support that breastfeeding and pregnant patients can benefit if they have a mild or moderate COVID-19 infection.

As of now, the Food and Drug Administration (FDA) has authorized the use of these medicines to treat COVID-19 for non-hospitalized adults and adolescents under what is referred to as an Emergency Use Authorization (EUA.) An EUA means the drugs have not undergone the same type of review as other FDA-approved products but meet certain criteria for safety, performance, and effectiveness in treating patients during the COVID-19 pandemic.

Both of these drugs are administered intravenously (through the vein) for at least an hour, and patients receive one dose of casirvimab and one dose of imdevimab. You will be monitored for 60 minutes after your infusion to monitor for side effects.

Like any drug, these two medicines have potential risks, so it’s essential to discuss their use with your physician, especially if you are pregnant or breastfeeding.

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