The efficacy of glatiramer acetate in beta-interferon-intolerant MS patients

Abstract
Glatiramer acetate (GA) is routinely used in multiple sclerosis (MS) patients who cannot tolerate or fail to respond to beta-interferon (IFN-beta). The aim of this study was to assess the efficacy and tolerability of GA in these patients. Fifteen relapsing-remitting MS patients who had discontinued IFN-beta therapy due to side effects were included in this open, 1-year prospective study. Neurologic examinations and laboratory assessments were performed every 3 months. The induction of MxA protein production was also evaluated. Eleven of fifteen patients (73%) tolerated GA well whereas four patients (27%) discontinued treatment due to side effects. The relapse rate reduced from 1.86 per year to 0.91 per year. Neither laboratory abnormalities nor MxA protein induction was found. GA can be considered as a good treatment alternative to IFN-beta-intolerant MS patients. However, some patients were not able to use available immunomodulative treatments, which emphasizes the need for new therapeutic options. The lack of MxA protein induction confirms the different mechanisms of action of GA and IFN-beta.