Rare Ophthalmological Diseases

Acute Optic Neuritis (AON) is an acute, rare inflammatory disease of the optic nerve. The classic triad of inflammatory optic neuritis consists of loss of vision, periocular pain and dyschromatopsia, and is unilateral in 70% of adults (Pau et al. Eye 2011). Inflammation of the optic nerve induces significant demyelination and axonal damage, leading to permanent visual dysfunction. Acute ON is closely related to Multiple Sclerosis as it is the initial presentation in approximately 20% of cases.

Standard of Care

Patients that suffer an AON episode are currently treated with IV corticosteroids for 3-5 days. This treatment may hasten recovery due to its strong anti-inflammatory effects, but it has no effect on visual outcome, which depends on axonal damage produced in the optic nerve during the inflammation.

Epidemiology

AON uses to happen in young people (20-40 years old). The incidence of new cases of AON has been historically estimated at 5/100,000 cases although recent epidemiological data suggests it may have increased (Martínez-Lapiscina et al. J Neurol. 2014).

Neuromyelitis Optica (NMO, also known as Devic’s disease) is a rare, chronic-relapsing inflammatory and demyelinating disease characterized mainly by recurrent and simultaneous attacks of optic neuritis and transverse myelitis. NMO is a severe and life-threatening disease as a high proportion of patients will become legally blind in one or both eyes and/or suffer from paralysis within 5 years of diagnosis. Eventually, death may occur due to severe myelitis leading to respiratory failure.

Standard of Care

NMO patients’ treatment is ineffective and includes IV corticosteroids for 3-5 days for acute relapses as well as immunosuppressive treatment to prevent relapses (e.g. azathioprine, mycophenolate or off-label rituximab and chemotherapy is often used). There are no approved efficacious therapies for preventing relapses nor for treating the disability associated with relapses.

Epidemiology

The condition has an estimated prevalence of 1-5/100,000 and the Guthy Jackson Charitable Foundation estimates there are around 10,000 patients in the US suffering from this severe disease.