Clinical and immune responses correlate in glatiramer acetate therapy of multiple sclerosis

Glatiramer acetate (GA) treatment for relapsing remitting multiple sclerosis (RRMS) leads to decreased GA-specific proliferative responses and a Th2 cytokine shift. To study a possible correlation between immunological and clinical responses to GA therapy, we prospectively followed RRMS patients clinically, by magnetic resonance imaging and by primary immunological assays. Fluctuation of GA-specific proliferative responses was significantly lower in treatment responders than in untreated patients, and GA-specific proliferative responses were increased during relapses. These associations suggest a possible causal relationship between immunological and clinical responses to GA therapy. Primary proliferation assays may thus be a useful marker for treatment response.