Gene therapy of rare diseases: another clinical study
Clinical trials of gene therapy for Fabry's disease have begun in Canada
These studies were preceded by successful trials of the method on a mouse model of the disease, a rare birth defect that affects only a few thousand people in the world, including 400 Canadians, including 25 residents of Calgary.
Fabry's disease is characterized by a deficiency or absence of the enzyme alpha-galactosidase A, which is necessary for the normal functioning of organs. Normally, the enzyme alpha-galactosidase A promotes the breakdown of a fatty substance called globotriazylceramide (GL-3). With a lack of this enzyme, GL-3 accumulates in cells. When GL-3 accumulates in kidney cells, serious disorders occur, including renal failure.
Fabry's disease manifests itself in a variety of symptoms – from mild to severe and life-threatening, such as kidney failure, heart disorders, stroke. The average life expectancy of people with Fabry disease without treatment is no more than 40 years.
The object of clinical trials of gene therapy was 34-year-old Calgary resident Christopher Armstrong, who was diagnosed with Fabry's disease in 2007.
About a billion bone marrow stem cells taken from the patient were sent to Jeffrey Medina's laboratory at the University of Toronto, where they were injected with a virus modified by a gene that is responsible for the synthesis of the enzyme alpha-galactosidase A.
As Professor Medin says, "we used a substantially modified lentivirus." "Firstly, it was devoid of pathogenicity and became safe, and secondly, a corrective functional alpha-galactosidase A gene was introduced into it, thanks to which cells began to produce a normal enzyme," the scientist explains. It is assumed that the gene will work in a similar way in the body of the stem cell donor, that is, in the patient.
Christopher Armstrong receives supportive enzyme replacement therapy, which does not cure diseases. Currently, the patient has a thickening of one of the walls of the heart.
According to scientists, the effectiveness of experimental gene therapy in this patient with Fabry's disease can be evaluated in two years.
Portal "Eternal youth" http://vechnayamolodost.ru30.01.2013