FDA Authorizes Use of Monoclonal Antibody Treatment for COVID-19

MONDAY, Nov. 23, 2020 -- A combination of two monoclonal antibodies was granted emergency use authorization (EUA) for the treatment of mild-to-moderate COVID-19, the U.S. Food and Drug Administration announced Saturday.

The combination of casirivimab and imdevimab, which must be administered together by intravenous infusion, is approved for use in treating patients ages 12 years and older and weighing at least 88 lb who have a high risk for progressing to severe COVID-19 (i.e., those ages 65 years and older and those with certain chronic medical conditions). The EUA does not apply to patients hospitalized with COVID-19 or those requiring oxygen therapy due to COVID-19. The FDA notes that monoclonal antibodies may be tied to worse outcomes for this patient population.

The FDA based its decision to grant the EUA on data from a randomized, double-blind, placebo-controlled clinical trial of 799 nonhospitalized patients with mild-to-moderate COVID-19. Patients were randomly assigned to receive either a single intravenous infusion of 1,200 mg casirivimab and 1,200 mg imdevimab (266 patients), 4,000 mg casirivimab and 4,000 mg imdevimab (267 patients), or placebo (266 patients) within three days of a positive SARS-CoV-2 viral test result. On day 7, patients treated with casirivimab and imdevimab had a larger reduction in viral load. Three and 9 percent of patients who received the antibody treatment and those who received placebo, respectively, were hospitalized or went to the emergency room. The findings were similar between the two doses of casirivimab and imdevimab.

"Authorizing these monoclonal antibody therapies may help outpatients avoid hospitalization and alleviate the burden on our health care system," FDA Commissioner Stephen Hahn, M.D., said in a statement.

The EUA was issued to Regeneron Pharmaceuticals Inc.

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Posted: November 2020