Drug-maker Regeneron Pharmaceuticals announced on Monday it has started late stage human testing of an antibody treatment for COVID-19. It said the tests are designed to show the drug’s effectiveness in preventing and treating the disease. Regeneron is launching one of the drug trials jointly with the U.S. National Institute of Allergy and Infectious Diseases (NIAID). The company said the goal is to test the drug’s ability to prevent infections in persons who have had close contact with a COVID-19 patient. Regeneron said it hopes the late-stage drug trial will involve about 2,000 patients across the United States.