Natalizumab is effective as second line therapy in the treatment of relapsing remitting multiple sclerosis

Natalizumab has been recommended for the treatment of patients with relapsing remitting multiple sclerosis with insufficient response to interferon-beta (IFN-beta) or glatiramer acetate (GA). Prospective, observational study. We found a reduction of the annualized relapse rate from 2.1 under IFN-beta or GA to 0.2 one year after switching to natalizumab. There were 94% fewer gadolinium enhancing lesions with natalizumab. Natalizumab reduced short term clinical and MRI activity in second line therapy and efficacy is comparable to first line therapy as demonstrated in the pivotal trials.