What is a Monoclonal Antibody?

Your body naturally makes antibodies to fight infection. However, your body may not have antibodies designed to recognize a novel (or new) virus, like SARS-CoV-2, the virus that causes COVID-19. Monoclonal antibodies, or mAbs, are made in a laboratory to fight a particular infection—in this case, SARS-CoV-2—and are given to patients directly with an infusion. That’s why mAb treatment may help patients who are at high risk for serious symptoms or having to stay in the hospital.

mAb treatment for COVID-19 is different from a COVID-19 vaccine. A vaccine triggers your body’s natural immune response but can take weeks to develop enough antibodies and prevent some kinds of infection. Some vaccines for COVID-19 require two shots, so your body can develop its own immune response to the disease. But if you already have the virus, mAb treatment gives your body the antibodies it needs to protect itself.