FDA halts use of 2 treatments found to be ineffective against omicronWASHINGTON — U.S. regulators restricted the use of a pair of COVID-19 monoclonal antibody therapies after scientific evidence suggested they are unlikely to be effective against the omicron variant. The Food and Drug Administration said in a statement on Monday that it had decided to limit access to the treatments, which are made by Eli Lilly & Co. and Regeneron Pharmaceuticals Inc., amid the recent surge in omicron infections. The variant, which was first detected last year in southern Africa, now accounts for nearly all new…