In this undated image from video provided by Regeneron Pharmaceuticals on Friday, Oct. 2, 2020, vials are inspected at the company's facilities in New York state, for efforts on an experimental coronavirus antibody drug. Antibodies are proteins the body makes when an infection occurs; they attach to a virus and help the immune system eliminate it. (Regeneron via AP)

In this undated image from video provided by Regeneron Pharmaceuticals on Friday, Oct. 2, 2020, scientists work with a bioreactor at a company facility in New York state, for efforts on an experimental coronavirus antibody drug. Antibodies are proteins the body makes when an infection occurs; they attach to a virus and help the immune system eliminate it. (Regeneron via AP)

In this undated image from video provided by Regeneron Pharmaceuticals on Friday, Oct. 2, 2020, a scientist works in the company's Infectious Disease Lab in New York state, for efforts on an experimental coronavirus antibody drug. Antibodies are proteins the body makes when an infection occurs; they attach to a virus and help the immune system eliminate it. (Regeneron via AP)