Siponimod to treat secondary progressive multiple sclerosis

Siponimod fumarate (BAF-312) is a synthetic sphingosine 1- phosphate (S1P) receptor modulator, which exerts immunomodulating effects mediated by B- and T-cell sequestration in secondary lymphoid organs. S1P receptor modulators have consistently shown a significant benefit on relapse rate and other measures of disease activity in patients with relapsing multiple sclerosis (MS), compared with both placebo and active comparator. However, most clinical trials of S1P receptor modulators--as well as other therapies for MS--lack evidence of a significant benefit on disability progression. A phase III trial of siponimod for secondary progressive MS showed a significant effect of the active drug compared with placebo on reduction of disability progression. Siponimod exhibits selective affinity for types 1 and 5 S1P receptors, indicating a possible lower risk of bradycardia and vasoconstriction compared with modulators with type 3 S1P receptor affinity. Current evidence supporting siponimod efficacy for secondary progressive MS is reviewed in the present article.