Regeneron’s (NSDQ:REGN) REGEN-COV remains one of the most effective monoclonal antibody therapies in reducing the risk of serious COVID-19 infections and resulting hospitalizations and deaths. A study recently published in the New England Journal of Medicine found that the drug effectively prevented COVID-19 disease in household contacts of individuals infected with the novel coronavirus.

When delivered subcutaneously, REGEN-COV was 81.4% effective at reducing the risk of symptomatic infections and led to a 92.6% reduction of symptomatic infections after the first week.

Consisting of the monoclonal antibodies casirivimab and imdevimab, REGEN-COV also appeared to accelerate the recovery of COVID-19-infected individuals. In recipients who received the drug, symptoms resolved two weeks faster than in placebo recipients.

Study investigators also found that the drug was generally well-tolerated.

“This peer-reviewed NEJM publication demonstrates that REGEN-COV provides rapid and robust protection to prevent SARS-CoV-2 infection, and follows data showing that REGEN-COV maintains effectiveness against all variants of concern,” said Dr. George D. Yancopoulos, president and CSO at Regeneron, in a statement.

The study involved 1505 participants 12 or older. Among the 753 participants in the REGEN-COV group, 11 (1.5%) developed symptomatic COVID-19 compared. Conversely, 59 out of 752 placebo recipients (7.8%) developed symptomatic disease. The relative risk reduction was 81.4%.