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Generation 2+ antisense drug

ION363 is a Generation 2+ antisense drug designed to prevent the production of the Fused in Sarcoma (FUS) protein. It is being developed as a potential therapy for an inherited form of amyotrophic lateral sclerosis (ALS) in patients with mutations in the FUS gene. FUS-ALS is the third most common inherited form of ALS1. Mutant FUS causes motor neuron degeneration through a toxic gain of function mechanism2. In patients, mutant FUS protein aggregates in motor neurons3. Antisense-mediated reduction of mutant FUS protein in a FUS-ALS mouse model prevents motor neuron loss. It is hypothesized that reduction of FUS protein will reverse or prevent disease progression in FUS-ALS patients.

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.4About 15 to 20 percent of all ALS cases are familial, and FUS-ALS accounts for approximately 5 percent of familial ALS. Like all ALS, people with FUS-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.