Subcutaneous injection of antibody cocktail reduces risk for symptomatic SARS-CoV-2
One subcutaneous injection of REGEN-COV — a combination of two monoclonal antibodies — reduced the risk for symptomatic SARS-CoV-2 infection by more than 80% among household contacts of infected individuals, Regeneron said.
The finding, announced in a press release, was from a phase 3 trial run by Regeneron and the National Institute of Allergy and Infectious Diseases. The cocktail includes the monoclonal antibodies casirivimab with imdevimab.
“These data suggest that REGEN-COV can complement widespread vaccination strategies, particularly for those at high risk of infection. Importantly, to date REGEN-COV has been shown in vitro to retain its potency against emerging COVID-19 variants of concern," Myron S. Cohen, MD, who heads monoclonal antibody efforts for the NIH-sponsored COVID Prevention Network and is director of the Institute for Global Health & Infectious Diseases at the University of North Carolina at Chapel Hill, said in the release.
According to the release, the phase 3, double-blind, placebo-controlled trial assessed the effect of REGEN-COV on uninfected individuals without anti-SARS-CoV-2 antibodies or any COVID-19 symptoms who lived in the same household as an individual who tested positive for SARS-CoV-2 within the prior 4 days. In total, the researchers randomly assigned 1,505 people who were not infected with SARS-CoV-2 to receive either one 1,200 mg dose of REGEN-COV or placebo, given subcutaneously.
The study demonstrated that REGEN-COV “rapidly protected” household contacts from exposure, with 72% protection against symptomatic infections in the first week and 93% in subsequent weeks. The protection was 81% through 29 days, the primary endpoint Additionally, the study showed that individuals treated with REGEN-COV who experienced a symptomatic infection experienced resolved symptoms in just 1 week compared with 3 weeks with placebo, and they cleared the virus faster, according to the release.
Adverse events (AEs) in the study occurred in 20% (n = 265 out of 1,311) of participants in the treatment arm and 29% (n = 379 out of 1,306) of participants in the placebo arm, with serious AEs occurring in 1% (n = 10) of REGEN-COV and 1% (n = 15) of placebo participants.
The FDA has authorized the emergency use of casirivimab and imdevimab for use in patients aged 12 years or older with a positive SARS-CoV-2 test who are at risk for progression to severe COVID-19. Regeneron said it will share the new data with the FDA and request an emergency use expansion to include COVID-19 prevention for appropriate populations, according to the press release.
“If authorized, convenient subcutaneous administration of REGEN-COV could help control outbreaks in high-risk settings where individuals have not yet been vaccinated, including individual households and group living settings," Cohen said.