FDA Expands Authorization of Regeneron’s COVID-19 Antibody Cocktail

FDA recently updated the emergency use authorization for Regeneron’s investigational COVID-19 antibody cocktail, REGEN-COV. 

The authorization now includes post-exposure prophylaxis in individuals at high risk of severe disease who are not fully vaccinated or may not mount an adequate response to vaccination and who have been exposed to SARS-CoV-2 or are at high risk of exposure due to institutional setting.

Providers can now administer REGEN-COV monthly to those who require dosing for ongoing exposure. Notably, this is the only COVID-19 antibody therapy currently available across the US for both treatment and post-exposure prophylaxis.

"Today's FDA authorization enables certain people at high risk of developing severe COVID-19 infection to access REGEN-COV if they have been exposed to the virus — the first time an antibody treatment has been authorized for this purpose," George D. Yancopoulos, MD, PhD, president and chief scientific officer of Regeneron, said in the recent announcement. 

"We continue to work with the FDA as it undertakes its review of REGEN-COV in a broader group of people including in a pre-exposure prophylactic setting for people who are immunocompromised, and in patients hospitalized due to COVID-19,” Yancopoulos continued. 

Under the updated authorization for post-exposure prophylaxis, providers can administer REGEN-COV by subcutaneous injection or intravenous infusion. 

A single 1,200-milligram dose of REGEN-COV can be followed by subsequent repeat dosing of the cocktail 600 milligrams once every four weeks in infected individuals.  

The treatment should continue for duration of the ongoing response, a Regeneron spokesperson explained. 

FDA based its decision on a Phase 3 trial, which enrolled 1,505 individuals who were not infected with SARS-CoV-2 at baseline and received either one 1,200 milligram dose of REGEN-COV or placebo. 

Researchers found that the cocktail reduced the risk of symptomatic infection by 81 percent in individuals who were not infected when they entered the trial. 

And in June, REGEN-COV reduced risk of death by 20 percent in patients hospitalized with COVID-19 who had not mounted their own immune response.

The Phase 3 UK RECOVERY trial found that 24 percent of patients in the REGEN-COV group died compared to 30 percent of patients in the standard care group. 

Additionally, there was no longer a significant effect on 28-day mortality when combining the larger seropositive group with the seronegative group. 

The new indication follows the November 2020 FDA authorization of REGEN-COV to treat non-hospitalized patients. 

The November authorization allows healthcare providers to administer REGEN-COV intravenous infusion to infected adults and pediatric patients 12 years of age or older. 

Providers may also administer the drug combination to individuals at high risk of progressing to severe COVID-19 and to patients 65 years of age or older who have certain underlying conditions.