GlaxoSmithKline has become the first big pharma company to file a gene therapy approval case to the European Medicines Agency (EMA). The therapy, developed in collaboration with San Raffaele Hospital and the Telethon Foundation in Italy, is designed to cure a disease called adenosine deaminase (ADA) deficiency, which causes severe combined immunodeficiency syndrome, lead to serious infections and, ultimately, death.
ADA affects an estimated 350 children worldwide (around 30 children are born with this genetic defect each year). The current, expensive, therapy involves bovine enzyme replacement and requires frequent injections and lacks so far in efficacy. GSK’s therapy is designed to treat around 90% of these children for whom no suitable bone marrow donor can be found.
The drug (GSK2696273) is a gene therapy which uses an adeno-associated virus vector to insert working copies of the ADA gene into the stem cells extracted from the bone marrow of patients. The cells are then reintroduced into the patient, so they can repair the immune system and enable the body to make normal genes on its own.