Vaccine Info

Bamlanivimab and Etesevimab Monoclonal Antibodies

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Last reviewed
December 19, 2023

Bamlanivimab and Etesevimab COVID-19 Monoclonal Antibody

Eli Lilly's Bamlanivimab (LY-CoV555) neutralizing IgG1 monoclonal antibody (mAb) is directed against the spike protein of the SARS-CoV-2 coronavirus. Bamlanivimab was designed to block viral attachment and entry into human cells, thus neutralizing the virus and potentially preventing and treating COVID-19 patients. Bamlanivimab emerged from the collaboration between Lilly and AbCellera. Lilly scientists developed the mAb in less than three months and tested them at the NIAID Vaccine Research Center. Bamlanivimab and etesevimab do not have any COVID-19 virus in themEtesevimab (LY-CoV016, JS016) is a recombinant, fully human monoclonal neutralizing antibody. Eli Lilly licensed etesevimab from Junshi Biosciences after jointly developed by Junshi and the Institute of Microbiology, Chinese Academy of Science.

On February 9, 2021, the U.S. FDA authorized bamlanivimab and etesevimab to be administered together to treat mild-to-moderate COVID-19 in adults and certain pediatric patients. On December 3, 2021, the FDA issued a revised EUA for bamlanivimab and etesevimab (previously authorized for pediatric patients 12 years of age and older weighing at least 40 kilograms, or about 88 pounds), to additionally authorize bamlanivimab and etesivimab administered together for the treatment of mild to moderate COVID-19 in all younger pediatric patients, including newborns, who have a positive COVID-19 test and are at high risk for progression to severe COVID-19, including hospitalization or death. In addition, this revision also authorizes bamlanivimab and etesevimab to be administered together for post-exposure prophylaxis to prevent COVID-19 in all pediatric patients, including newborns, at high risk of progression severe COVID-19, including hospitalization or death. On May 11, 2021, the US Centers for Medicare & Medicaid Service (CMS) confirmed the investigational monoclonal antibody therapies are available under FDA EUA.

As of January 24, 2022, the U.S. Food and Drug Administration (FDA) revised the authorization for bamlanivimab and etesevimab administered together to limit their use to only when the patient is likely to have been infected with or exposed to a variant that is susceptible to these treatments. The EUA for bamlanivimab and etesevimab, administered together, was issued initially on February 9, 2021. The FDA revoked the EUA for bamlanivimab and etesevimab, which were administered together on December 14, 2023. Lilly informed the FDA that all lots of bamlanivimab and etesevimab manufactured and labeled for use under EUA 094 have expired. Lilly does not intend to offer this product in the United States anymore. Since September 13, 2021, about   850,000 treatments have been shipped in the U.S. 

AbCellera is a Canadian technology company that searches, decodes and analyzes natural immune systems to find antibodies that its partners can develop into drugs to prevent and treat disease. For more information, visit

Based in Indianapolis, Indiana, Eli Lilly (LLY) is a global healthcare leader that unites caring with discovery to create medicines that make life better for people worldwide. To learn more about Lilly, please visit For more information about Lilly's COVID-19 therapies authorized for emergency use, contact the Lilly COVID Hotline at 1-855-LillyC19 (1-855-545-5921).

Etesevimab Monoclonal Neutralizing Antibody

Etesevimab binds explicitly to the SARS-CoV-2 surface spike protein receptor-binding domain high affinity and can block the binding of the virus to the ACE2 host cell surface receptor. In addition, point mutations were introduced into the native human IgG1 antibody to mitigate effector function. As a result, the U.S. FDA published a revised Fact Sheet on March 20, 2021. Junshi Biosciences has completed a similar Phase 1 study in healthy volunteers in China and globally and has initiated Phase 1b/2 trials in COVID-19 patients. Junshi Biosciences (HKEX: 1877; SSE: 688180) leads development in Greater China, while Lilly leads growth worldwide. A Phase 2 study assessing the efficacy and safety of bamlanivimab alone and bamlanivimab with other neutralizing antibodies versus placebo to treat symptomatic low-risk COVID-19 in the outpatient setting (BLAZE-4. NCT04634409) has completed enrollment.

Bamlanivimab and Etesevimab COVID-19 Antibody Availability

A current list of countries with purchase agreements and regulatory authorization is found on this Eli Lilly webpage.

Bamlanivimab and Etesevimab COVID-19 Antibody Treatment Indication for Children

Bamlanivimab and etesevimab were authorized on December 3, 2021, as the first and only neutralizing antibody therapy for emergency use in COVID-19 patients under the age of 12; the EUA was extended for the pediatric and infant population.

Bamlanivimab and Etesevimab COVID-19 Treatment Side Effects and Safety

There are limited clinical data available for bamlanivimab and etesevimab. Serious and unexpected adverse events that have not been previously reported using bamlanivimab and etesevimab together may occur.

Bamlanivimab and COVID-19 Covaccination

A non-peer-reviewed study published on December 16, 2021, suggests a complementary role for COVID-19 mAbs with COVID-19 vaccines and that the benefit of receiving COVID-19 vaccination at the earliest opportunity outweighs the minimal effect on the endogenous immune response due to prior prophylactic COVID-19 mAb infusion. The impact of An-2 monoclonal antibody, bamlanivimab, on the endogenimpactss immune response to COVID-19 vaccination study. All bamlanivimab and placebo study participants mounted a robust immune response following full COVID-19 vaccination, irrespective of age, risk category, and vaccine type, with any observed differences unlikely to be clinically meaningful. 

Bamlanivimab and Etesevimab COVID-19 Antibody Treatment News

June 1, 2020 - Eli Lilly and Company announced that patients had been dosed in the world's first study of a potential antibody treatment to fight COVID-19.

Bamlanivimab COVID-19 Antibody Treatment Clinical Trials

Eli Lilly continues to test Bamlanivimab in clinical trials.

Clinical Trials