Key clinical point: Among patients with secondary progressive multiple sclerosis who received siponimod or placebo during a double-blind trial and entered an open-label extension, those who received siponimod throughout the study were less likely to experience disability progression and had a lower annualized relapse rate up to 5 years later, compared with patients who initially received placebo and switched to siponimod.

Major finding: For the 25th percentile of patients, continuous siponimod treatment corresponded to a delay of 54% (21 months vs. 13.6 months). Risk of worsening on the Symbol Digit Modalities Test was reduced by 23% in the continuous siponimod–treatment group. For the 25th percentile of patients, this reduced risk corresponded to a delay of 62% (29.6 months vs. 18.3 months). The annualized relapse rate was 0.054 in the continuous-siponimod group, compared with 0.097 in the group that switched to siponimod from placebo, a reduction of 52%.

Study details: An analysis of data from patients in the EXPAND core and extension studies. In EXPAND, 1,651 patients were randomized, 1,224 entered the open-label extension, and 878 remained in the study at the April 2019 data cutoff.

Disclosures: The study authors disclosed research support and personal compensation from Novartis, which markets siponimod, and other pharmaceutical companies. Several coauthors were Novartis employees.