A U.S. subsidiary of Italy's privately held Leadiant Biosciences SpA has won FDA approval for Revcovi (elapegademase-lvlr), a new recombinant enzyme replacement therapy (ERT) for the ultra-rare genetic disorder adenosine deaminase severe combined immune deficiency. The condition, which affects as few as one in 1 million live births in the U.S., leaves infants and young children vulnerable to infections and can be fatal if not diagnosed and treated by age 2.