HLA-DRB1*1501 and response to copolymer-1 therapy in relapsing-remitting multiple sclerosis

Background: Copolymer 1 (Cop-1) is a random synthetic amino acid copolymer, effective in the treatment of the relapsing-remitting form of MS (RRMS). I n vitro and in vivo studies suggest that the mechanism of Cop-1 involves it s binding to major histocompatibility complex class II molecules as an init ial step. Objective: To assess a possible relationship between human leukoc yte antigen (HLA) alleles and response to Cop-1 therapy. Methods: Eighty-th ree patients with RRMS, 44 treated with Cop-1 and 39 with interferon beta - 1a (IFN beta -1a) for 2 years, were typed by molecular methods for HLA clas s 11 genes and subgrouped according to clinical outcome. Results: Data have shown a possible positive correlation between presence of DRB1*1501 and re sponse to Cop-1 therapy (p = 0.008). No relationship between HLA alleles an d therapy has been found in IFN beta -1a treated patients. Conclusions: Res ults suggest that DRB1*1501 might be relevant for the clinical outcome in C op-1 treated patients and, if confirmed in larger studies, it could be help ful in the selection of RRMS patients for different therapeutic options.