On Aug. 4, 2021, Regeneron announced that the New England Journal of Medicine (NEJM) had published positive detailed results from a Phase 3 trial that assessed the ability of REGEN-COV (casirivimab and imdevimab) to prevent COVID-19 infection among household contacts of SARS-CoV-2 infected individuals. The trial met its primary endpoint, reducing the risk of symptomatic infections by 81% (p<0.001), with a 93% reduction of symptomatic infections after the first week, and no dose-limiting toxicities observed.

Regeneron previously announced initial results from the Phase 3 trial, which was jointly run with the COVID-19 Prevention Trials Network (CoVPN) National Institute of Allergy and Infectious Diseases
(NIAID), part of the National Institutes of Health (NIH)

REGEN-COV use is increasing across the U.S. following the latest surge, with recent weekly orders surpassing 50,000 doses. In addition to the increasing proportion of patients who now receive REGEN-COV, Regeneron continues to work to ensure all healthcare providers and people who may benefit from this important therapy are aware of its availability.

Multiple analyses, including a recent publication in Cell, have shown that REGEN-COV retains potency against the main variants of concern circulating within the U.S., including Delta (B.1.617.2; first identified in India), Gamma (P.1; first identified in Brazil) and Beta (B.1.351; first identified in South Africa). Consequently, REGEN-COV remains available for use across the U.S., and Regeneron will continue actively monitoring the potency of REGEN-COV against emerging variants.

Regeneron was collaborating with Roche to increase global supply of the antibody cocktail, with Roche primarily responsible for development and distribution outside the U.S. Regeneron and Roche share a commitment to making the antibody cocktail available to COVID-19 patients around the globe and will support access in low- and lower-middle-income countries through drug donations to be made in partnership with public health organizations.