As the omicron BA.2 subvariant has spread, FDA has announced that it will further constrain the use of the investigational monoclonal antibody sotrovimab. The agency announced that it would limit the use of the antibody in some U.S. regions last week. GlaxoSmithKline plc (LSE/NYSE:GSK) and Vir Biotechnology (Nasdaq:VIR) were initially confident that the antibody could…