 Passage Bio, Inc. PASG, a genetic medicines company focused on developing transformative therapies for rare, monogenic central nervous system disorders, today announced that the U.S. Food and Drug Administration FDA has granted Orphan Drug Designation to its lead product candidate, PBGM01, for the treatment of infantile GM1 gangliosidosis GM1. GM1 is a rare and often life-threatening monogenic recessive lysosomal storage disease caused by mutations in the GLB1 gene that results in rapidly progressing neurodegeneration. Infantile GM1 is an incredibly devastating disease that impacts one of our most vulnerable populations, said Bruce Goldsmith, Ph.D, chief executive officer of Passage Bio. 