The trial is being carried out and coordinated by the Institut Pasteur (the trial’s sponsor), Inserm, AFM-Téléthon and Vaincre les Maladies Lysosomales (VML). It is being conducted at Bicêtre Hospital (AP-HP) in Paris. Scientists and medical professionals consider that the patient’s very young age – two and a half years old –increases the chances of the therapy’s success Three other children will be enrolled into the trial over the coming months.
10 years of collaborative research
This clinical trial is the result of 10 years of collaborative research carried out by Professor Jean-Michel Heard and his team at the Institut Pasteur (Biotherapies for Neurodegenerative Diseases Unit, Institut Pasteur/Inserm U1115) in partnership with AFM-Téléthon to the tune of 7 million euros.
Produce the missing enzyme
The treatment consists of several intracerebral vector deposits in several areas of the brain. It is based on the development of a viral vector capable of delivering one of the four potentially mutated genes in Sanfilippo patients (corresponding to four essential lysosomal enzymes) to the patient’s brain cells. This trial focuses on the B form of the disease. Cells incorporate the missing gene, provided by the viral vector, into their DNA thus enabling them to produce the missing enzyme and stop the disease
Open the door to future applications
Due to the slow progression of Sanfilippo syndrome, benefits of the treatment on the natural progression of the disease will not be appreciated before several years. This trial, if successful, could also open the door to future applications of the viral vector in gene therapy treatments, particularly in the treatment of neurodegenerative diseases.
Sanfilippo syndrome is a rare genetic disease (also referred to as an orphan disease) that affects approximately 1 in 100,000 children. It is caused by a gene mutation that affects lysosomes – organelles that play essential roles in cell functions – including digestion and protein recycling mechanisms. The first symptoms of the disease – hyperactivity, speech disorders - arise at roughly 2 years of age and lead to neurodegeneration, progressive hearing loss, gradual loss of autonomy and premature death, in most cases before the age of 20. There is currently no cure or treatments available to address either the symptoms or the progression of the disease.