Researchers from the Boston Children's Cancer and Blood Disorders Center developed a new gene therapy that is effective and safe for treating a life-threatening condition that affects the immune system.
The severe combined immunodeficiency syndrome (SCID-X1), also known as the "bubble boy disease," affects the body's ability to produce antibodies and cells that fight infection. In most cases, the condition leads to leukemia, and if left untreated, most boys diagnosed with the disease will die before their first birthdays. The disease affects less than 200,000 people in the United States, or 1 in 50,000 live births.
Early clinical data trials showed that the new gene therapy is efficient in preventing late-developing leukemia in at least 25 percent of the bubble boy patients involved in the trials.
Eight of nine boys who were part of the study are still alive after 12 to 38 months of treatment. They also displayed no apparent signs of SCID-X1-related infections. Furthermore, the therapy was successful in improving the function of the immune system in seven of the eight patients.
Further genetic analysis of the T-cells, which play an important role in the immune system, showed that the treatment prevented the progression of the cancer-causing genes.
Researchers will monitor the outcomes of the treatment, and will examine if the patients will manifest any signs of leukemia for the next 15 years. In Europe, where previous clinical trials for the gene therapy were conducted, the patients were diagnosed with leukemia 2 to 5 years after the treatment.
"Our goal was to take the molecular data from the prior trial and use it to produce a vector that would remain effective and at the same time reduce the risk of leukemia," David A. Williams, MD, a leader of Dana-Farber/Boston Children's, chief of the Division of Hematology/Oncology and director of clinical and translational research at Boston Children's Hospital, and lead investigator said in a press release.
He further explained that the team will continue to improve the safety of the treatment, and that it is too early to resolve whether the new gene therapy is successful in removing the risks of leukemia.
Further details of the study were published in the Oct. 9 issue of the New England Journal of Medicine.
