When the long-awaited moment arrived, a nurse helped Adam Hess loosen a tiny plastic clamp on an intravenous line leading to the chest of his son, who lay asleep in a bed at Boston Children’s Hospital.
Millions of stem cells that were collected from 6-year-old Conner Hess’s blood in January flowed through the IV and entered his bloodstream. They had been modified in a lab by adding a functional gene to compensate for a defective one. Conner’s doctors expect that this groundbreaking gene therapy, which costs a staggering $3 million a patient, will stave off a fatal degenerative brain disease and save his life.
