VANCOUVER, BC—Patients with relapsing-remitting multiple sclerosis (MS) treated with daclizumab high-yield process (HYP) had improved cognitive outcomes at 96 weeks compared with interferon-β-1a, a study presented at the 68th AAN Annual Meeting has found.

The Phase 3 active-controlled DECIDE study randomly assigned patients to receive daclizumab HYP 150mg subcutaneously every 4 weeks (n=919) and interferon-β-1a 30mcg intramuscularly weekly (n=922) for a minimum of 96 weeks up to 144 weeks. The Symbol Digit Modalities Test (SDMT, oral response format) was administered at baseline and every 24 weeks until the patient’s last study visit.

To report cognitive outcomes, Ralph H. B. Benedict, PhD, Professor of Neurology at the Jacob School of Medicine and Biomedical Sciences, University of Buffalo, and The State University of New York, Buffalo, NY, and colleagues analyzed changes in SDMT score from baseline post hoc using a mixed effects model.

“Clinically meaningful improvement and worsening were defined using validated cutoffs of ≥3- and ≥4-point changes from baseline SDMT scores,” he noted. “Treatment differences in the proportion of patients showing clinically meaningful improvement or worsening were evaluated used the generalized estimating equations approach with a logistic model.” 

At baseline, patient characteristics were found to be similar between the treatment groups.

At Weeks 96 and 144, mean SDMT scores showed greater improvement in patients treated with daclizumab HYP vs interferon-β-1a. In addition, “a significantly higher proportion of patients showed clinically meaningful SDMT improvements at Weeks 96 and 144” with daclizumab HYP using both cutoffs, Dr. Benedict noted.

At Weeks 24, 72, and 96, “significantly fewer patients showed clinically meaningful declines in SDMT score” with daclizumab HYP using a 3-point cutoff and at Week 24 using a 4-point cutoff. “A trend toward significance was observed at Week 144 using a 3-point cutoff, as well as at Weeks 72 and 96 using a 4-point cutoff,” he stated.

At Week 96, the SDMT score for those treated with daclizumab HYP had improved by +4.08, compared to +2.89 for interferon-β-1a (P=0.0274). A ≥3-point improvement in SDMT scores was 60% for those treated with daclizumab HYP and, for ≥4 improvements, 55.4%. For patients in the interferon-β-1a arm, the corresponding improvements were 54.1% (P=0.0153) and 50.1% (P=0.366), respectively.

For declines in SDMT scores, the trends were similar. The percentage of patients treated with daclizumab HYP  who experienced a ≥4-point decline compared with those who received interferon-β-1a was significantly lower at Week 24, 20.4% vs. 24.8% (P=0.0268). Differences at Week 72 were 18.2% vs. 21.5% and, for Week 96, 17.5% vs. 21.1%.

“These data demonstrate that daclizumab HYP treatment leads to long-lasting improvements in cognitive outcomes in patients with relapsing-remitting MS vs. interferon-β-1a, particularly visual processing speed and attention,” Dr. Benedict concluded. 

The study was sponsored by Biogen and AbbVie Biotherapeutics Inc. Dr. Benedict has received consulting fees and research support from Biogen.