Skip to content
You are now leaving to visit


Generation 2+ antisense drug

ION541, also known as BIIB105, is an investigational antisense medicine targeting ataxin 2 (ATXN2) RNA. It is designed to prevent the production of ATXN2 protein and is being developed as a potential therapy for sporadic Amyotrophic Lateral Sclerosis (ALS), and other indications. About 90% of ALS1 is sporadic, with no apparent familial history. Aggregates of TDP-43 protein in motor neurons is a pathological hallmark of sporadic ALS and induces toxicity in motor neurons. ATXN2 has been shown to modulate TDP-43 toxicity2-3. In addition, human genetic data has also identified a link between ATXN2 and ALS4. It is hypothesized that reduction of ATXN2 will ameliorate the underlying TDP-43 pathology and reverse or prevent disease progression in sporadic ALS1.

About Amyotrophic Lateral Sclerosis

ALS is a rare, fatal neurodegenerative disorder characterized by loss and dysfunction of neurons in motor pathways with a prevalence of approximately five cases per 100,000 persons in the U.S.1 There are two forms of ALS: inherited (familial) and sporadic. The sporadic form accounts for about 90% all ALS cases. People with ALS suffer progressive degeneration of motor neurons, which results in a declining quality of life and ultimately death. People with ALS experience muscle weakness, loss of movement, difficulty in breathing and swallowing and eventually succumb to their disease. Currently, treatment options for patients with ALS are extremely limited with no drugs that significantly slow disease progression.