Background and purposeIn the SELECT study, treatment with daclizumab high-yield process (DAC HYP) versus placebo reduced the frequency of gadolinium-enhancing (Gd+) lesions in patients with relapsing-remitting multiple sclerosis (RRMS). The objective of this post hoc analysis of SELECT was to evaluate the effect of DAC HYP on the evolution of new Gd+ lesions to T1 hypointense lesions (T1 black holes).
MethodsSELECT was a randomized double-blind study of subcutaneous DAC HYP 150 or 300mg or placebo every 4weeks. Magnetic resonance imaging (MRI) scans were performed at baseline and weeks 24, 36 and 52 in all patients and monthly between weeks 4 and 20 in a subset of patients.
MRI scans were evaluated for new Gd+ lesions that evolved to T1 black holes at week 52. Data for the DAC HYP groups were pooled for analysis.
ResultsDaclizumab high-yield process reduced the number of new Gd+ lesions present at week 24 (P=0.005) or between weeks 4 and 20 (P=0.014) that evolved into T1 black holes at week 52 versus placebo. DAC HYP treatment also reduced the percentage of patients with Gd+ lesions evolving to T1 black holes versus placebo.
ConclusionsTreatment with DAC HYP reduced the evolution of Gd+ lesions to T1 black holes versus placebo, suggesting that inflammatory lesions that evolved during DAC HYP treatment are less destructive than those evolving during placebo treatment.