EXPAND (Exploring the efficacy and safety of siponimod in patients with secondary progressive multiple sclerosis) was an event- and exposure-driven double-blind trial that recruited patients with SPMS over a 2-year period starting in February 2013. Of 1,651 patients who were recruited, randomized, and actually received treatment, 1,099 were treated with oral siponimod, 2 mg once daily, and 546 were given a matching placebo.
Treatment was for up to 3 years or until 374 CDP events assessed via the Expanded Disability Status Scale (EDSS) had occurred. Patients who had CDP after 6 months in the double-blind trial could be re-consented and continue with double-blind treatment, switch to open-label siponimod, or stop study treatment and either remain on no treatment or receive another disease-modifying treatment.
On average, the patients had been diagnosed with SPMS for a mean of 3.8 years and had been first diagnosed with MS around 17 years prior to this.
The primary endpoint of the trial – CDP at 3 months – was first reported in 2016 at the annual congress of the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS). CDP was defined as a 0.5- to 1-point increase in EDSS depending on the baseline score.