The Food and Drug Administration (FDA) has authorized revisions to the facts sheets for monoclonal antibody products used in the treatment of COVID-19 to include information on how certain SARS-CoV-2 variants may impact the effectiveness of the treatments.

The fact sheets for bamlanivimab, bamlanivimab and etesevimab, and REGEN-COV (casirivimab and imdevimab) have been updated to include specific information on the B.1.1.7 (UK Origin), B.1.351 (South Africa Origin), P.1 (Brazil Origin), B.1.427/B.1.429 (California Origin), and B.1.526 (New York Origin) variants. These therapies have all been granted Emergency Use Authorization for the treatment of mild to moderate COVID-19 in adults and pediatric patients (12 years of age and older weighing at least 40kg) with positive results of direct SARS-CoV-2 viral testing, and who are at high risk for progressing to severe COVID-19 and/or hospitalization.

As there is a potential risk of treatment failure due to the development of these variants, health care providers are urged to consider the prevalence of monoclonal antibody resistant variants in their area when considering treatment options.

In addition to reviewing the authorized fact sheets for this information, the Centers for Disease Control and Prevention’s data on variant proportions in the US can be used as a resource to identify new and emerging SARS-CoV-2 variants.

For more information visit


FDA authorizes revisions to fact sheets to address SARS-CoV-2 variants for monoclonal antibody products under emergency use authorization. [press release]. Silver Springs, MD: US Food and Drug Administration; March 18, 2021.