Targeted DOK7 gene therapy for Congenital Myasthenic Syndromes
Congenital Myasthenic Syndromes (CMS) are a group of genetically and phenotypically heterogeneous, neuromuscular transmission disorders characterized by muscle weakness (myasthenia) that worsens with physical exertion.
DoK-7 (Downstream of tyrosine kinase 7) is a key regulator of neuromuscular junction (NMJ) formation. Homozygous loss-of or reduction of-function mutations in the human DOK7 gene underlie a limb-girdle type of CMS characterized by NMJs that are about half the normal size. DoK-7 CMS is an orphan disease estimated to affect 3,600 people worldwide. Patients with DoK-7 CMS have a decreased Quality of Life (QoL) due to exercise intolerance, dependency on intermittent respiratory support, and/or tube feeding by adulthood (2/3 of the patients). Moreover, about half of the patients will need a wheelchair for ambulation, and the other half will require walking aids. No cure nor standardized treatment has been yet developed for DoK-7 CMS.
Amplo Biotechnology is developing AMP-101, the first gene therapy product for DoK-7 CMS. The treatment is based on a recombinant adeno-associated virus serotype 9 (AAV9) vector carrying the human DOK7 gene. The new product will enable a shift in the current clinical practice from chronic administration of drugs to alleviate symptoms to a one-off treatment, administered through a single intravenous injection. The solution will allow physicians to treat the entire affected population, curing adult disease, and stopping disease progression in children.