Neuromyelitis optica, also known as Devic’s disease, occurs when the body’s immune system reacts against otherwise healthy nervous system cells in the optic nerves and spinal cord, and sometimes in the brain. Neuromyelitis optica often is misdiagnosing as multiple sclerosis (MS), but neuromyelitis optica is a distinct condition by more severe attacks and less complete recovery.
A single neuromyelitis optica attack can leave a patient blind or paralyzed. With each relapse, disability can worsen. It affects up to 10 in 100,000 people. Currently, the immunosuppressive therapies used to prevent neuromyelitis optica relapses have not approved by the Food and Drug Administration. Furthermore, 25 to 60 % of patients receiving these medications continue to have recurring attacks, the authors note.
The Evaluation of Eculizumab
In the Prevention of Relapses and Evaluation of Eculizumab in NMOSD Treatment (PREVENT) study; 143 adults enrolled at 70 sites in 18 countries. All patients had aquaporin-4 immunoglobulin G (AQP4-IgG), an antibody associated with most neuromyelitis optica cases. Patients could continue on their prior therapy if desired. In addition, patients randomized to receive regular doses of a placebo or IV eculizumab.
The study found that treatment with eculizumab reduced the risk of relapse by 94 %, compared with a placebo. At 48 weeks, nearly 98 % of patients treated with eculizumab had not relapsed, compared with 63 % for patients on the placebo. “This study offers hope to patients since each attack in NMO can cause loss of visual or motor function. “Stopping attacks can prevent disability and allow patients to maintain function and a better quality of life.”
Treating neuromyelitis optica
Therefore the Mayo Clinic is a recognized center of excellence for diagnosing and treating neuromyelitis optica. In 2002, Mayo Clinic researchers led by Claudia Lucchinetti, M.D., and colleagues the unique pathological features of NMO and proposed that NMO is an autoimmune disease caused by one or more harmful antibodies. In 2004, Vanda Lennon, M.D., Ph.D., Brian Weinshenker, M.D., and Mayo colleagues reported the discovery of the AQP4-IgG biomarker, a blood test that differentiates neuromyelitis optica from MS and similar disorders.
Eculizumab has used to treat disorders where complement activation causes harm; such as myasthenia gravis, a muscle disease, and paroxysmal nocturnal hemoglobinuria, a genetic disease affecting red blood cells. In an early phase clinical trial, the Mayo team observed a near complete cessation of neuromyelitis optica attacks. Based on those early results, this large multicenter, international study was performed.
Side effects of eculizumab include risk of meningococcal infections. Study participants vaccinated against meningococcal infections, and no cases reported. One person receiving eculizumab died of an infection that was not with complement inhibition. This study only enrolled patients with AQP4-IgG antibodies, so the findings cannot be extrapolated to other inflammatory central nervous system disorders. The long-term effect of eculizumab in patients with neuromyelitis optica requires further study, the authors note.