On Sept. 29, 2021, Regeneron announced that the New England Journal of Medicine (NEJM) published positive detailed results from a Phase 3 trial that assessed the ability of REGEN-COV (casirivimab and imdevimab) to treat COVID-19 in infected high-risk non-hospitalized patients (outpatients).

The trial met its primary and all secondary endpoints and showed treatment with REGEN-COV significantly reduced the risk of hospitalization or death, with a safety profile consistent with previously reported data.