P Foley, P Reilly, A Coulson, JI O’Riordan



Multiple sclerosis is a leading cause of disability in young adults, with the Scottish population suffering the highest prevalence in Europe. Disease-modifying therapies, including beta-interferon (IFN-b), are increasingly used to minimise relapse frequency in the majority of patients who present with a relapsing-remitting disease pattern. Unfortunately, neutralising antibodies (NABs) may develop against IFN-b and are associated with reduced efficacy. These antibodies may be detected using a serum sample. Despite the importance of this problem, from both a patient’s perspective and a wider community and economic standpoint, there is no universally agreed protocol for the use of NAB testing. Authorities variously suggest routine ‘screening’ testing or, conversely, testing only in specific situations. In Scotland, routine testing is seldom used. We report our experience of routine NAB testing in 105 patients (of whom 35 were NAB-positive) over two years in NHS Tayside and comment on its cost and implications.

Keywords Interferon, multiple sclerosis, neutralising antibody

Declaration of Interests Dr O’Riordan has been a principal investigator inclinical trials sponsored by Merck Serono, Teva and Bayer Schering. He has also been a consultant to, or lectured at meetings sponsored by, Merck Serono, Teva, Bayer Schering and Biogen Idec. NHS Tayside is currently participating in the Department of Health’s Risk Sharing Scheme on Disease Modifying Therapies in Multiple Sclerosis.