By Mariam Sunny and Khushi Mandowara (Reuters) -The U.S. Food and Drug Administration (FDA) on Friday approved Pharming Group’s drug to treat a rare genetic disorder that leads to a weakened immune system, the Dutch company said. Leniolisib, to be sold under the brand name Joenja, becomes the first approved drug in the United States to treat activated phosphoinositide 3-kinase delta syndrome (APDS), a primary immunodeficiency that affects about 1 to 2 people in a million. Pharming’s U.S.-listed shares rose 22% to $13.75. Joenja is expected to launch in the U.S. in early April and w...