To alleviate the progress of fatal neurological diseases, gene therapy has positive clinical results

At the 27th Annual Meeting of the European Society of gene and cell therapy, axovant gene therapies announced today that preliminary clinical data showed that gene therapy axo-aav-gm2 has the potential to alleviate the disease progression of children with Tay Sachs disease (TSD) Axo-aav-gm2 not only enables children with TSD to reach a normal development milestone, but also improves the myelination of the brain TSD, also known as GM2 ganglioside disease, is caused by mutations in the HEXA and Hexb genes These mutations damage the function of enzyme protein, which leads to the accumulation of toxic gangliosides in the central nervous system The patient developed neurodegenerative disease, cognitive impairment, paralysis and early death The average life expectancy of children with this fatal lysosomal storage disease is only 3-4 years At present, there are no therapies that can change the progress of the disease Axo-aav-gm2 gene therapy of axovant company aims to introduce genes encoding normal functional enzyme protein into patients with AAV9 and aavrh8 virus vectors respectively, so as to improve their survival and enable children to reach key development milestones In preclinical animal experiments, the gene therapy can increase the enzyme activity, reduce the deposition of gangliosides, and improve the survival period of animals in a dose-dependent manner Source: reference [2] The available preliminary clinical data are from two children with TSD From the third to the sixth month after gene therapy, the activity of hex a enzyme in cerebrospinal fluid (CSF) of the first advanced TSD patient increased three times compared with baseline At the sixth month, compared with the baseline, the motor ability score measured by the chop-intent evaluation method increased from 14 to 18, and maintained at this level The second child reached a normal development milestone at the third month after receiving gene therapy, and the patient's neurological examination was normal MRI showed that the brain structure of the patient was normal, and myelination was consistent with the development of normal brain in this age The activity of hexa in patients also improved from baseline, and increased to 1.8% of normal enzyme activity (it is expected that when the enzyme activity exceeds 0.5% of normal enzyme activity, it will bring clinically significant effect) Compared with the baseline, the chop-intent score increased from 58 to 60 and remained at this level Two patients remained stable after gene therapy In addition, axo-aav-gm2 also showed good safety and tolerance "Myelination is an important part of brain development in healthy children, but it is usually abnormal in children with TSD," said Dr Gavin Corcoran, chief development officer of axovant "We are very happy to see the improvement of myelination and neuromuscular stability in 10 month old patients." reference material: [1] Axovant Presents First Evidence of Clinical Stabilization in Tay-Sachs Disease at the European Society of Gene and Cell Therapy 27th Annual Congress, Retrieved October 23, 2019, from http://investors.axovant.com/news-releases/news-release-details/axovant-presents-first-evidence-clinical-stabilization-tay-sachs [2] Axovant Corporate Presentation Retrieved October 23, 2019, from http://investors.axovant.com/static-files/a412afd5-62de-43ef-8c75-6d495b113447 A kind of