ION260, also known as BIIB132, is an investigational antisense medicine designed to reduce the production of ataxin 3 (ATXN3) protein. Patients with a trinucleotide repeat expansion in the ATXN3 gene develop Spinocerebellar Ataxia Type 3 (SCA3). Preclinical studies have shown that lowering of ATXN3 protein is associated with decreased progression of SCA3-like disease.
About Spinocerebellar Ataxia Type 3
SCA3, also known as Machado-Joseph disease, is the most common form of ataxia, characterized by progressive movement dysfunction speech difficulties, uncontrolled muscle tensing, muscle stiffness, involuntary eye movements and tremors. SCA3 is ultimately fatal with patients usually surviving 10 to 20 years after symptom onset.
Safety and efficacy have not been evaluated by any regulatory authorities for the indications described.