FDA revises EUAs for Regeneron, Lilly antibody treatments

Jan. 26, 2022

The U.S. FDA is revising its authorization of two monoclonal antibody treatments for COVID-19 — previously granted emergency authorization — based on new data which shows the treatments are unlikely to be effective against the omicron variant. 

The two antibody treatments — bamlanivimab and etesevimab (administered together) produced by Eli Lilly, and REGEN-COV produced by Regeneron — were granted emergency use authorization from the FDA in February 2021 and November 2020, respectively. 

Both treatments were shown to be mostly ineffective against the omicron variant, which accounts for 99% of COVID-19 cases in the U.S. as of January 15. To prevent unwanted side effects such as injection site reactions or allergic reactions the FDA has decided to limit use of the treatments at this time. 

The FDA decision comes days after it approved Gilead’s remdesivir for outpatient use. The drug is approved for use in adults and pediatric patients with mild-to-moderate COVID-19 who are at high risk of severe COVID-19, according to Patrizia Cavazzoni, director of the FDA’s Center for Drug Evaluation and Research. The revision also comes as the FDA is paying more attention to drugs with accelerated approval. The administration may reauthorize the treatments for use if they are effective against potential new variants, Cavazzoni added.

Other therapies are popping onto the market that are also likely to be effective against the omicron variant, including a single-dose intravenous monoclonal antibody from GSK and Vir Biotechnology called sotrovimab which was granted Emergency Use Authorization by the FDA back in May. Pfizer and Merck & Co both received FDA approval for their antiviral pills. Pfizer’s Paxlovid was authorized on December 21, with Merck’s molnupiravir approved days later.