On Nov. 12, 2021, Regeneron announced that the U.S. Food and Drug Administration had extended by three months its review of the Biologics License Application (BLA) for REGEN-COVﾮ (casirivimab and imdevimab) to treat COVID-19 in non-hospitalized patients and as prophylaxis in certain individuals.

The extension was due to ongoing discussions with the FDA on pre-exposure prophylactic use, for which Regeneron had submitted additional data from its completed prophylaxis trial that the FDA had accepted for review. The FDA considered the submission of these additional data to be a Major Amendment to the BLA and provided a new target action date of Jul. 13, 2022.