Glatiramer acetate: long-term safety and efficacy in relapsing-remitting multiple sclerosis.

Glatiramer acetate (GA) is approved for relapsing-remitting multiple sclerosis in 57 countries worldwide, with more than 2 million patient-years of exposure and over 20 years of continuous clinical use without new safety concerns. GA has an overall favorable risk-benefit profile: 30% reduced annual relapse rate and decreased brain lesion activity. In clinically definite MS or clinically isolated syndrome, GA slows brain atrophy, which may be related to its unique anti-inflammatory and neuroprotective mechanisms of action. Early treatment with GA delays the onset of clinically definite MS more effectively than late treatment in clinically isolated syndrome. GA is not associated with immunosuppression, autoimmune disease, infections or development of neutralizing antibodies. A new three-times-weekly formulation of GA is available to potentially reduce the incidence of injection-related side effects. Other safety advantages of GA include its pregnancy rating (Category B) and limited uncontrolled data suggesting that tolerability is similar in children with MS.