Patients suffering from SCID conditions lack several types of blood lymphocytes, white blood cells formed in lymphatic tissue that assure protection against infections. Without treatment, SCID is lethal in the first year. Scientists studied five patients enrolled in a gene therapy clinical trial in France for nearly a year. They detected lymphocytes in the cells 30 days after gene therapy in all patients but one. The developing lymphocytes appear to function normally, both in vitro and after patient immunization.
Scientists look to expand the study to further confirm the current clinical results.
Initial results from a second gene therapy study signify success for a non-viral, external treatment of hemophilia A that may transform the care of patients. This is the first human investigation of gene therapy in this condition. It results in lifelong recurrent bleeding and dependence on intravenous infusions of factor VIII to control hemorrhage. A subgroup of the treated cells that express the necessary, therapeutic protein are isolated and characterized prior to injection back into the patient. Preclinical studies reveal safe and durable expression of the human factor VIII gene at levels that exceed five percent of normal or greater for one year following a single treatment.