OBJECTIVE: To assess prior immunosuppressant (IS) use, natalizumab treatment duration and anti-JCV antibody status as risk factors for PML in MS patients being treated with Natalizumab.
BACKGROUND KNOWLEDGE: Prevalence of anti-JCV antibody positivity in PwMS is ~54%.
RESULTS: Risk of PML on Natalizumab
CONCLUSIONS: The combined effect of prior immunosuppressant use and natalizumab treatment duration identifies subpopulations of patients at lower or higher risk of developing PML. Anti-JCV antibody testing is an additional promising risk stratification tool being evaluated in ongoing studies.
“PwMS will find this information helpful in deciding on whether or not to start or stop Natalizumab treatment based on their JCV serostatus, previous treatment history and duration of Natalizumab treatment.”
COI: I was the Chief UK Investigator on the AFFIRM study and have received consultancy fees from Biogen-Idec and Elan Pharmaceuticals in relation to the development of Natalizumab