Among patients with secondary progressive multiple sclerosis (MS) 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. This research was presented online as part of the 2020 American Academy of Neurology Science Highlights.
Benefits of siponimod gained during the controlled period were “sustained for up to 5 years, suggesting a continuous effect of siponimod and underlining the advantages of early treatment initiation with siponimod,” the researchers said. Incidence rates of adverse events during the extension study were consistent with those during the controlled treatment period.
The results “highlight the critical importance of early treatment intervention … to ensure the best possible long-term outcomes for patients with MS who are experiencing progression,” study investigator Bruce Cree, MD, PhD, said in a news release.
“It’s never too early to stay ahead of progression in MS, since the early identification of physical and cognitive changes – even subtle ones – can indicate MS disease progression and therefore allow for timely intervention.” said Dr. Cree, who is clinical research director and George A. Zimmermann Endowed Professor in Multiple Sclerosis at the University of California, San Francisco.
Siponimod, marketed as Mayzent, is a sphingosine 1-phosphate receptor modulator that selectively binds to S1P1 and S1P5 receptors. The oral drug was approved by the Food and Drug Administration in 2019 for the treatment of relapsing forms of MS, including clinically isolated syndrome, relapsing remitting disease, and active secondary progressive disease in adults.
To assess the long-term efficacy and safety of siponimod in patients with secondary progressive MS, Dr. Cree and colleagues analyzed data from patients in the controlled and extension parts of the EXPAND trial. Patients could have had been in the study for as long as 5 years at the data cutoff in April 2019. Efficacy analyses included time to 3-month confirmed disability progression on the Expanded Disability Status Scale (EDSS), time to 6-month confirmed disability progression, time to 6-month confirmed worsening of 4 or more points on the Symbol Digit Modalities Test (SDMT), and annualized relapse rate. In EXPAND, the researchers defined confirmed disability progression as a 1-point increase in EDSS if the baseline score was 3.0-5.0, or a 0.5-point increase if the baseline score was 5.5-6.5.
“Of the 1,224 (74% of 1,651 randomized) patients entering the extension, 878 (72%) were ongoing,” the researchers reported. Patients who received siponimod continuously were less likely to experience 3-month confirmed disability progression and 6-month confirmed disability progression, relative to patients who switched from placebo. In addition, patients who received continuous siponimod treatment had a prolonged time to 6-month confirmed disability progression, compared with patients who switched from placebo. 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 SDMT 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). ARR 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%.
Dr. Cree has received personal compensation from Novartis, which markets siponimod, as well as Akili, Alexion, Atara, Biogen, EMD Serono, and TG Therapeutics. His coauthors reported receiving research support and personal compensation from Novartis and other pharmaceutical companies. Several coauthors were Novartis employees.
SOURCE: Kappos L et al. AAN 2020, Abstract S40.003.
This story originally appeared on MDedge.com.