|Small study shows non-viral gene therapy for hemophilia A is safe|
June 11, 2001
Researchers have shown that a new system of delivering a clotting factor gene to hemophiliacs is safe. The new approach involves removing fibroblast cells from each patient, introducing a healthy copy of the factor VIII gene, and then injecting these modified cells back into the patient. The researchers did not detect immune responses to the modified cells in any of the six patients that participated in the study.
Hemophilia A is caused by defects in the blood-clotting factor VIII gene, which causes spontaneous bleeding in joints, soft tissues and organs throughout life. The severity of the disease depends upon the quantity of the blood-clotting gene. The six patients in the study all had severe hemophilia A, which is characterized by factor VIII levels below one percent of normal.
After treatment, four of the six patients showed elevated levels, which were accompanied by decreased bleeding and a reduced need for prophylactic administration of factor VIII.
"There is still a lot of work that needs to be done on these and other patients before we can move on to future studies to formally evaluate efficacy," David Roth, of Beth Israel Deaconess Medical Center, Boston, was quoted as saying. "But we are optimistic based on the clinical responses we observed, especially in light of the modest increases in factor VIII activity achieved at this early stage," he added.
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