Science

In central nervous system inflammatory diseases, such as Multiple Sclerosis (MS), autoimmune reactions cause inflammation leading to destruction of myelin and myelinated axons in the visual pathway, resulting in chronic visual impairment and loss of quality of life. Two forms of visual impairment associated with MS are Acute Optic Neuritis (AON) and Chronic Optic Neuropathy (CON).

Many people with MS, will experience attacks of AON, characterized by subacute onset of pain and diminished vision, usually in one eye. Acute optic neuritis is often treated with corticosteroids and most people recover from individual attacks within a few months. CON on the other hand, is a more debilitating condition characterized by serious visual impairment, with irreversible loss of vision. CON does not respond to corticosteroid or disease modifying immunomodulatory MS treatment. There is a major unmet medical need to find safe and effective treatments that can repair damaged myelin in the optic nerve and visual tracts of the brain to preserve axonal function and restore vision in CON.

Up to 50% of people with MS will experience an episode of optic neuritis during the course of their disease. In the United States, there are an estimated prevalence of 90,000 people who suffer from Chronic Optic Neuropathy.

There are other forms of Optic Neuropathy that are distinct from CON and AON. These include Neuromyelitis Optica (NMO) and Myelin Oligodendrocyte Glycoprotein Antibody Disease (MOGAD) that also involve loss of myelin in the optic nerve due to specific inappropriate auto-immune responses leading to destruction of central nervous system myelin. These are rare chronic diseases that can lead to worsening of vision until blindness. NMO and MOGAD each have a prevalence of approximately 10,000 people in the United States.