(HealthDay)—For patients with secondary progressive multiple sclerosis, the selective sphingosine 1-phosphate (S1P) receptor1,5 modulator, siponimod, is associated with reduced relative risk of confirmed disability progression, according to a study published online March 22 in The Lancet. Ludwig Kappos, M.D., from the University of Basel in Switzerland, and colleagues conducted a phase 3 trial at 292 hospital clinics...