Federal supply of the one monoclonal antibody treatment that has proven effective is now "limited," with more doses expected in January, a Health and Human Services spokesperson said. Major hospitals in the New York region say they have stopped using monoclonal antibody therapies because they have run out of the one treatment that appears to be effective against the omicron variant of the coronavirus, leaving doctors without a vital tool to treat severely ill Covid-19 patients. New York University and Valley Health System in northern New Jersey notified doctors Sunday... Meanwhile, Mount Sinai Health System in New York said it...