FDA authorizes lower dose of Regeneron antibody cocktail for COVID-19
The FDA has authorized a lower dose of Regeneron’s antibody cocktail to treat COVID-19, which the company said may help more patients access the treatment.
In an updated emergency use authorization (EUA), the FDA lowered the dose to 1,200 mg — 600 mg of casirivimab and 600 mg of imdevimab — which is half the dose that was authorized under the original EUA issued in November.
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The updated EUA also allows the cocktail, called REGEN-COV, to be delivered subcutaneously “when IV infusion is not feasible and would lead to a delay in treatment.”
REGEN-COV is available for free from the U.S. government to treat patients aged 12 years or older with mild-to-moderate COVID-19 who are at high risk for progression to severe COVID-19, including hospitalization or death.
"Despite increased use of vaccines, thousands of patients are still becoming infected in the United States every day, with many at high risk of serious complications from COVID-19. Unfortunately, to date, only a fraction of patients eligible for antibody treatments have received them, which we hope will change based on this updated FDA authorization," Regeneron President and Chief Scientific Officer George D. Yancopoulos, MD, PhD, said in a news release.
The updated EUA was based on the results of several trials, including a phase 3 trial that was presented recently at the American Thoracic Society International Conference that demonstrated a consistent treatment effect between the two doses.
In its treatment guidelines, the Infectious Diseases Society of America suggests using REGEN-COV or another antibody cocktail containing bamlanivimab and etesevimab to treat ambulatory patients with mild-to-moderate COVID-19 who are at risk for progression to severe disease.
References:
IDSA. Guidelines on the treatment and management of patients with COVID-19. https://www.idsociety.org/practice-guideline/covid-19-guideline-treatment-and-management/. Accessed June 7, 2021.