Giovannoni et al. A randomized, double-blind, placebo-controlled study to evaluate the safety and efficacy of daclizumab HYP monotherapy in relapsing-remitting multiple sclerosis: primary results of the SELECT trial.
Background: Daclizumab HYP (DAC HYP) is a humanized monoclonal antibody specific for the alpha subunit (CD25) of the human IL-2 receptor. DAC HYP modulates IL-2 signaling in-vivo and causes an expansion of CD56^bright natural killer cells.
Objective: To evaluate the safety and efficacy of DAC HYP monotherapy in patients with relapsing-remitting MS (RRMS).
Methods: We randomly assigned 600 patients with clinically definite RRMS and at least one MS relapse in the prior 12 months or one new Gd+ lesion in the prior 6 weeks to receive either DAC HYP 150 mg or DAC HYP 300 mg or placebo as a subcutaneous injection once every 4 weeks for 52 weeks. The primary endpoint was the annualized relapse rate (ARR).
Conclusions: Monthly, subcutaneous DAC HYP monotherapy demonstrated a robust and clinically meaningful effect on MS activity, including evidence for early impact on disability progression. These benefits and risks warrant further evaluation.
“These results are very interesting and surprising. Firstly, DAC works in an interesting way by targeting a messenger in the immune system called IL2, it blocks in binding to its high affinity receptor. Secondly, DAC had an impact on disability in a 52 week study; this is very unusual finding in a one year study that is traditionally too short to see an impact on disability. The latter suggests DAC may be a very effective therapy in relapsing MS.”