Shares of Regeneron Pharmaceuticals Inc. /zigman2/quotes/203149337/composite REGN -1.46% gained 0.1% in premarket trading on Wednesday after the company said its COVID-19 antibody therapy cut the risk of death in patients who have been hospitalized by 20%. This is the first time clinical research has demonstrated that Regeneron's antibody treatment has improved survival for hospitalized patients. The study, which is being conducted in the U.K. in patients who have not yet developed antibodies, follows other research that showed the company's antibody treatment can improve recovery times among people with mild or moderate forms of the disease. Regeneron said it is planning to ask the Food and Drug Administration to expand the emergency-use authorization in the U.S. to include these types of patients. Regeneron's stock is up 9.2% so far this year, while the broader S&P 500 /zigman2/quotes/210599714/realtime SPX -0.54% has gained 13.0%.