Researchers have uncovered a new gene therapy that can replace a deficient enzyme in patients suffering from the neurodegenerative disorders Tay-Sachs and Sandhoff. In a pair of separate studies, they were able to show the feasibility and efficacy of gene transfer in preclinical models.
Scientists were able to successfully deliver the therapeutic gene to the brains of treated mice, which restored enzyme function and extended survival by more than twofold.
Results of the tests were recently published in Human Gene Therapy and were titled "Novel Vector Design and Hexosaminidase Varieant Enabling Self-Complementary Adeno-Associated Virus for the Treatment of Tay-Sachs Disease" and "Systemic Gene Transfer of a Hexosaminidase Variant Using a scAAV9.47 Vector Corrects GM2 Gangliosidosis in Sandhoff Mice.”
A team from the University of North Carolina and Queen’s University in Canada along with researchers from SickKids and University of Toronto New Hope Research Foundation of Minnesota and the University of Manitoba developed a specialized adeno-associated virus (AAV) vector that delivered a gene coding for portions of the alpha and beta subunits of the enzyme that are defective in the Tay-Sachs and Sandhoff mice.
"This important proof-of-concept study sheds important information on the optimal design of rAAV vectors for this class of disorders," Dr. Terence Flotte of the University of Massachusetts Medical School told News Medical.
Still, the success of breakthrough gene therapies remain tempered by drug prices. In May, the developer of the world’s first gene therapy, UniQure ($QURE), gave up its efforts to get FDA approval for Glybera, which treats an ultrarare disease called lipoprotein lipase deficiency.
First approved in Europe in 2012, the drug carries a price tag of $1 million.
- check out the News Medical article