Pellkofer HL, Krumbholz M, Berthele A et al.
Ludwig Maximilians University, Munich, Germany.
Neurology 2011;76:1310–5.
Editor’s note: Neuromyelitis optica (NMO) is a rare but severe demyelinating inflammatory disease of the central nervous system that preferentially affects the spinal cord and optic nerves and is generally considered a variant of classical multiple sclerosis (MS). It has been associated with antibodies against aquaporin-4, a water channel expressed on astrocytes, and evidence supports a central role of antibody-generating B cells in the etiology of NMO. Although well-controlled clinical trials providing evidence of efficacy are lacking, classic immunosuppressants are generally used to treat this disease. Recent small, uncontrolled trials have suggested potential efficacy of the B-cell depleting monoclonal anti-CD20 antibody rituximab (Arch Neurol 2008;65:1443–8), which is considered a potential second-line treatment in NMO. Depletion of B cells by rituximab usually lasts for several months (N Engl J Med 2008;358:676–88).