Nearly a year on, Victoria Gray, who was the first person in the US to undergo a CRISPR-based treatment for sickle-cell disease, is doing well, NPR reports.
Vertex Pharmaceuticals and CRISPR Therapeutics launched a trial last year in which doctors remove cells from patients' bone marrow and edit them to produce fetal hemoglobin, before re-introducing the edited cells into the patients. Initial tests from last November suggested that Gray's cells were, as hoped, producing fetal hemoglobin and to a greater extent than researchers estimated would be needed to ease her disease symptoms.
According to NPR, the Sarah Cannon Research Institute's Haydar Frangoul and his colleagues gave an update on Gray's case and two beta-thalassemia cases at the European Hematology Association meeting earlier this month. It reports that 46 percent of Gray's hemoglobin is fetal hemoglobin, that fetal hemoglobin is present in 99.7 percent of her red blood cells, and that 81 percent of her bone marrow cells harbor the genetic alteration.
"To have it work in this way is extremely thrilling to see and extremely exciting," Frangoul tells NPR.