Positive Phase II Results With Subcutaneous Daclizumab in MS
Relapsed rate reduced by up to 54% at 1 year (Apr. 4)
Results from a phase IIb clinical study of daclizumab high-yield process (DAC HYP, Biogen Idec) have been published online in The Lancet. The SELECT trial was designed to determine the efficacy and safety of DAC HYP in patients with relapsing-remitting multiple sclerosis (RRMS).
Both 150-mg and 300-mg subcutaneous injections of DAC HYP, administered once every 4 weeks, met the study’s primary endpoint by significantly reducing the annualized relapse rate (ARR) by 54% (P < 0.0001) and 50% (P = 0.0002), respectively, compared with placebo at 1 year. In addition, DAC HYP reduced multiple sclerosis (MS) brain lesions compared with placebo.
Both doses of DAC HYP also met key secondary endpoints by significantly reducing the proportion of patients who relapsed at 1 year, as well as MS brain lesion activity, including the cumulative number of new gadolinium-enhancing (Gd+) lesions between weeks 8 and 24 and the number of new or newly enlarging T2-hyperintense lesions at 1 year. Further, as a tertiary endpoint, the findings demonstrated that DAC HYP had a positive effect on slowing disability progression, as measured by the Expanded Disability Status Scale (EDSS).
The overall incidence of adverse events (AEs) and treatment discontinuations was similar in all study groups (79% in the placebo group; 73% in the DAC HYP 150 mg group; and 76% in the DAC HYP 300 mg group). Serious adverse events, excluding MS relapse, occurred in 6% of the placebo group, in 7% of the DAC HYP 150 mg group, and in 9% of the DAC HYP 300 mg group.
DAC HYP is a humanized monoclonal antibody that binds to CD25, a receptor subunit that is expressed at high levels on T cells, which are thought to become abnormally activated in autoimmune conditions, such as MS. Previous clinical trials showed that DAC HYP increases CD56bright natural killer (NK) cells, which target the activated immune cells that can play a key role in MS, without causing general immune-cell depletion.