Asymptomatic Reactivation of JC Virus in Patients Treated with Natalizumab

• Published in: The New England journal of medicine Vol. 361; no. 25; pp. 2487 - 2490
• Main Authors: Gorelik, Leonid, Goelz, Susan, Sandrock, Alfred W
• Format: Journal Article
• Language: English
• Published: United States Massachusetts Medical Society 17-12-2009
• Subjects: Antibodies, Monoclonal - adverse effects; Antibodies, Monoclonal - therapeutic use; Antibodies, Monoclonal, Humanized; Humans; Integrin alpha4 - immunology; JC Virus - isolation & purification; JC Virus - physiology; Leukocytes, Mononuclear - virology; Multiple sclerosis; Multiple Sclerosis, Relapsing-Remitting - drug therapy; Natalizumab; Plasma; Studies; Urine; Viral Load; Viremia; Virus Activation - drug effects
• ISSN: 0028-4793; 1533-4406
• DOI: 10.1056/NEJMc0909622

To the Editor:
Chen and colleagues (Sept. 10 issue)
1
describe an increased prevalence of JC virus DNA in 19 patients with multiple sclerosis after 12 to 18 months of treatment with natalizumab. These findings contrast with results from other groups
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–
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and large studies by Biogen Idec and Elan Pharmaceuticals
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(Table 1).
Data from one ongoing study showed no increase in the prevalence of JC virus in plasma, urine, or peripheral-blood mononuclear cells (PBMCs) after 12 months of natalizumab treatment
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; another showed no increase in the presence of JC virus in serum for up to 30 months.
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A third . . .