Daclizumab in treatment of multiple sclerosis patients.

BACKGROUND: Daclizumab is a humanized monoclonal antibody (mAb) that blocks the interleukin-2 receptor alpha subunit (IL-2R-alpha chain; CD25) expressed on activated T cells leading to the inhibition of T-cell expansion, thus strongly reduces brain inflammation in patients with multiple sclerosis (MS). Another mechanism is significant expansion of CD56 (bright) natural killer (NK) cells that in turn inhibit T-cell survival. OBJECTIVE: At the Partners MS center, we have been using Daclizumab in an open-label fashion in patients who fail first line therapy or non-standard immunosuppressive treatment. Our aim was to assess its safety and tolerability in our patient population.