Regeneron Pharmaceuticals Inc. signage is displayed outside their headquarters in Tarrytown, N.Y., U.S., on June 12, 2020. Regeneron Pharmaceuticals Inc. said it had begun human trials of a new antibody cocktail for Covid-19, part of an ambitious clinical-testing plan that could lead to a new treatment option by the end of summer if all goes well. Photographer: Michael Nagle/Bloomberg via Getty Images