Regeneron Pharmaceuticals today announced the results from a Phase 3 trial jointly run with the National Institute of Allergy and Infectious Diseases (NIAID), which assessed the use of a single dose of investigational REGEN-COV, a monoclonal antibodies drug, to prevent COVID-19 in uninfected individuals.

The new analyses show REGEN-COV reduced the risk of contracting COVID-19 (i.e., laboratory-confirmed symptomatic SARS-CoV-2 infections) by 81.6% during the pre-specified follow-up period (months 2-8), maintaining the 81.4% risk reduction during the first month after administration, which was previously reported in The New England Journal of Medicine.

“Today’s new data demonstrate how a single dose of REGEN-COV can help protect people from COVID-19 for many months after administration. These results demonstrate that REGEN-COV has the potential to provide long-lasting immunity from SARS-CoV-2 infection, a result particularly important to those who do not respond to COVID-19 vaccines including people who are immunocompromised.”

Myron S. Cohen, Global Health & Infectious Diseases Director at the University of North Carolina

In results previously published, the trial met its primary endpoint, reducing the risk of COVID-19 (i.e., laboratory-confirmed symptomatic SARS-CoV-2 infections) by 81.4% within 1 month of receiving REGEN-COV (p<0.0001).

The new results released today describe a pre-specified analysis for the following 7 months, throughout which an additional 45 symptomatic infections occurred. During this time period, REGEN-COV continued to prevent infection, without requiring additional doses.