Neurologic consequence of delaying glatiramer acetate therapy for multiple sclerosis: 8-year data

To assess the long-term effectiveness of continuous glatiramer acetate (GA) therapy in relapsing-remitting multiple sclerosis (RRMS).

This open-label extension followed a randomized, placebo-controlled, double-blind study of GA of approximately 30 months duration. Patients originally randomized to GA continued on it (group A) and those randomized to placebo switched to GA (group B).

Of 251 original patients, 142 (56.6%) remained in the study after 8 years. Annual relapse rate for both groups declined to approximately 0.2 (approximately one relapse every 5 years). However, a significantly larger proportion of patients in group A had stable or improved Expanded Disability Status Scale scores compared with group B (65.3% vs 50.4%, respectively; P = 0.0263), possibly attributable to the delay of GA treatment for approximately 30 months in group B. GA was well tolerated and no drug-related laboratory changes were observed.

These data support early initiation of GA therapy as an efficacious and well-tolerated long-term treatment for RRMS patients.