Glatiramer Acetate: from Bench to Bed and Back.

BACKGROUND: Glatiramer acetate (GA, Copaxone®, Copolymer1, Cop 1) is an approved drug for the treatment of relapsing-remitting multiple sclerosis (RRMS). Its efficacy in reducing the frequency of exacerbations and its safety profile establish it as a first-line therapy for MS. Evidence from the animal model experimental autoimmune encephalomyelitis (EAE) and from MS patients indicate that GA affects various levels of the innate and the adaptive immune response, inducing deviation from the pro-inflammatory to the anti-inflammatory pathways. This includes mainly the induction of Th2/3 and T-regulatory cells, and down-regulation of both Th1 and Th17 cells. The immune cells induced by GA reach the CNS and secrete in situ anti-inflammatory cytokines, alleviating the pathological processes. In addition to its immunomodulatory activities, GA promotes neuroprotective repair processes such as secretion of neurotrophic factors, remyelination and neurogenesis, indicating that repair process in the CNS can be up-regulated by therapy.