What Is a Monoclonal Antibody for COVID-19?

Medically Reviewed on 12/13/2021
What Is a Monoclonal Antibody for COVID-19
Monoclonal antibodies for COVID-19 are lab-produced antibodies that can prevent the SARS-CoV-2 virus from attaching to cells

The FDA has issued an emergency use authorization (EUA) for monoclonal antibodies (mAbs) for the treatment of COVID-19 under specific conditions.

Antibodies are proteins produced by a type of immune cells (B cells) in the body that attack harmful cells in response to infection. The site on the pathogen to which the antibody binds is called an antigen epitope. 

Monoclonal antibodies for COVID-19 are lab-produced antibodies that can prevent the SARS-CoV-2 virus from attaching to cells. They are produced from a single clone of B cells and target the same antigen epitope on the virus. mAbs against SARS-CoV-2 are called anti-SARS-CoV-2 mAbs. They have specific epitopes on the spike protein present on the surface of the coronavirus, which play a crucial role in allowing the entry of the virus into the host cell and thus causing COVID-19.

The FDA has issued EUA to four types of mAb treatments for the treatment of SARS-CoV-2 infection:

  • Bamlanivimab plus etesevimab
  • Casirivimab plus imdevimab
  • Sotrovimab
  • Tocilizumab

Who is eligible for monoclonal antibodies for COVID-19?

Anti-SARS-CoV-2 monoclonal antibodies (mAbs) may be used for the treatment of mild to moderate COVID-19 in adults and children (at least 12 years or older and weighing at least 88 lbs) with positive results of direct SARS-CoV-2 viral testing and who are at a high risk of progressing to severe COVID-19. The minimum body mass index for receiving anti-SARS-CoV-2 mAbs is 25.

Conditions that may act as high risk factors for progression to the severe disease include:

mAbs can be used in both non-hospitalized people and people hospitalized due to a reason other than COVID-19, provided that they have mild to moderate COVID-19. Anti-SARS-CoV-2 mAbs cannot be given if the affected person:

  • Is hospitalized for COVID-19
  • Requires oxygen therapy due to COVID-19
  • Is on chronic oxygen therapy due to underlying non-COVID-19-related comorbidity and requires an increase in oxygen flow rate from the baseline because of COVID-19

Anti-SARS-CoV-2 mAbs may be administered as a preventive therapy or postexposure prophylaxis for certain individuals, including people who are at high risk of SARS-CoV-2 infection and have a higher likelihood of progressing to serious illness if infected.

Can you get vaccinated against COVID-19 if you received monoclonal antibodies?

According to the CDC, people who have received anti-SARS-CoV-2 monoclonal antibodies (mAbs) must avoid vaccination against COVID-19 until at least 90 days have passed after the therapy is completed. This waiting period is a precautionary measure because anti-SARS-CoV-2 mAbs can interfere with the immune response generated by the body in response to the vaccine, rendering it less effective or ineffective.

If, however, a person vaccinated against COVID-19 gets the disease, they may be administered anti-SARS-CoV-2 mAbs regardless of the timing of vaccination. This may be done if there are no logistical or supply constraints limiting the availability of the authorized anti-SARS-CoV-2 mAbs.

Medically Reviewed on 12/13/2021
Image Source: iStock Images