Effect of siponimod on magnetic resonance imaging measures of neurodegeneration and myelination in secondary progressive multiple sclerosis: Gray matter atrophy and magnetization transfer ratio analyses from the EXPAND phase 3 trial.

BACKGROUND: Magnetic resonance imaging (MRI) measurements of gray matter (GM) atrophy and magnetization transfer ratio (MTR; correlate of myelination) may provide better insights than conventional MRI regarding brain tissue integrity/myelination in multiple sclerosis (MS). OBJECTIVE: To examine the effect of siponimod in the EXPAND trial on whole-brain and GM atrophy, newly formed normalized magnetization transfer ratio (nMTR) lesions, and nMTR-assessed integrity of normal-appearing brain tissue (NABT), cortical GM (cGM), and normal-appearing white matter (NAWM). METHODS: Patients with secondary progressive multiple sclerosis (SPMS) received siponimod (2 mg/day; n =1037) or placebo (n = 523). Endpoints included percentage change from baseline to months 12/24 in whole-brain, cGM, and thalamic volumes; change in nMTR from baseline to months 12/24 in NABT, cGM, and NAWM; MTR recovery in newly formed lesions. RESULTS: Compared with placebo, siponimod significantly reduced progression of whole-brain and GM atrophy over 12/24 months, and was associated with improvements in brain tissue integrity/myelination within newly formed nMTR lesions and across NABT, cGM, and NAWM over 24 months. Effects were consistent across age, disease duration, inflammatory activity subgroups, and disease severity. CONCLUSION: Siponimod reduced brain tissue damage in patients with SPMS as evidenced by objective measures of brain tissue integrity/myelination. This is consistent with central nervous system (CNS) effects observed in preclinical models. ClinicalTrials.gov number: NCT01665144.

Siponimod versus placebo in secondary progressive multiple sclerosis (EXPAND): a double-blind, randomised, phase 3 study.

BACKGROUND: No treatment has consistently shown efficacy in slowing disability progression in patients with secondary progressive multiple sclerosis (SPMS). We assessed the effect of siponimod, a selective sphingosine 1-phosphate (S1P) receptor1,5 modulator, on disability progression in patients with SPMS. METHODS: This event-driven and exposure-driven, double-blind, phase 3 trial was done at 292 hospital clinics and specialised multiple sclerosis centres in 31 countries. Using interactive response technology to assign numbers linked to treatment arms, patients (age 18-60 years) with SPMS and an Expanded Disability Status Scale score of 3·0-6·5 were randomly assigned (2:1) to once daily oral siponimod 2 mg or placebo for up to 3 years or until the occurrence of a prespecified number of confirmed disability progression (CDP) events. The primary endpoint was time to 3-month CDP. Efficacy was assessed for the full analysis set (ie, all randomly assigned and treated patients); safety was assessed for the safety set. This trial is registered with ClinicalTrials.gov, number NCT01665144. FINDINGS: 1651 patients were randomly assigned between Feb 5, 2013, and June 2, 2015 (1105 to the siponimod group, and 546 to the placebo group). One patient did not sign the consent form, and five patients did not receive study drug, all of whom were in the siponimod group. 1645 patients were included in the analyses (1099 in the siponimod group and 546 in the placebo). At baseline, the mean time since first multiple sclerosis symptoms was 16·8 years (SD 8·3), and the mean time since conversion to SPMS was 3·8 years (SD 3·5); 1055 (64%) patients had not relapsed in the previous 2 years, and 918 (56%) of 1651 needed walking assistance. 903 (82%) patients receiving siponimod and 424 (78%) patients receiving placebo completed the study. 288 (26%) of 1096 patients receiving siponimod and 173 (32%) of 545 patients receiving placebo had 3-month CDP (hazard ratio 0·79, 95% CI 0·65-0·95; relative risk reduction 21%; p=0·013). Adverse events occurred in 975 (89%) of 1099 patients receiving siponimod versus 445 (82%) of 546 patients receiving placebo; serious adverse events were reported for 197 (18%) patients in the siponimod group versus 83 (15%) patients in the placebo group. Lymphopenia, increased liver transaminase concentration, bradycardia and bradyarrhythmia at treatment initiation, macular oedema, hypertension, varicella zoster reactivation, and convulsions occurred more frequently with siponimod than with placebo. Initial dose titration mitigated cardiac first-dose effects. Frequencies of infections, malignancies, and fatalities did not differ between groups. INTERPRETATION: Siponimod reduced the risk of disability progression with a safety profile similar to that of other S1P modulators and is likely to be a useful treatment for SPMS. FUNDING: Novartis Pharma AG.

Safety and Efficacy of Siponimod (BAF312) in Patients With Relapsing-Remitting Multiple Sclerosis: Dose-Blinded, Randomized Extension of the Phase 2 BOLD Study.

IMPORTANCE: This dose-blinded extension of the phase 2 BOLD (BAF312 on MRI Lesion Given Once Daily) Study in relapsing-remitting multiple sclerosis provides evidence on disease activity and safety of a range of siponimod doses for up to 24 months. OBJECTIVE: To assess the safety and efficacy of siponimod for up to 24 months during the dose-blinded extension of the BOLD Study. DESIGN, SETTING, AND PARTICIPANTS: At extension baseline in a randomized clinical trial, patients taking siponimod continued at the originally assigned dose and patients taking placebo were rerandomized to the 5 siponimod doses. Initial treatment was titrated over 10 days. A total of 252 eligible patients were treated at specialized multiple sclerosis centers for this study conducted from August 30, 2010, through June 3, 2013. INTERVENTIONS: Siponimod at 10-mg, 2-mg, 1.25-mg, 0.5-mg, and 0.25-mg doses. MAIN OUTCOMES AND MEASURES: Safety assessment included blood tests, documentation of adverse events at regular scheduled visits and Holter monitoring; key efficacy measures were annualized relapse rate and magnetic resonance imaging lesion activity. RESULTS: Among the 252 eligible patients, the mean (SD) ages were 37.2 (8.4) years, 35.2 (9.1) years, 34.0 (7.6) years, 35.1 (9.2) years, and 36.8 (9.1) years in the 0.25-mg, 0.5-mg, 1.25-mg, 2-mg, and 10-mg groups. Of the 252 patients, 184 (73%) entered the extension and received siponimod (10 mg: n = 33; 2 mg: n = 29; 1.25 mg: n = 43; 0.5 mg: n = 29; and 0.25 mg: n = 50); 159 (86.4%) completed the dose-blinded extension. The incidence of adverse events was similar across treatment groups (10 mg: 87.9%; 2 mg: 89.7%; 1.25 mg: 88.4%; 0.5 mg: 96.6%; and 0.25 mg: 84.0%). Nine patients reported serious adverse events (2 mg: 3/29 [10.3%], 1.25 mg: 1/43 [2.3%], 0.5 mg: 4/29 [13.8%], and 0.25 mg: 1/50 [2.0%]; no serious adverse event was reported for more than 1 patient and no new safety signals occurred compared with the BOLD Study. Dose titration mitigated symptomatic bradycardic events. Reductions in mean (95% CI) gadolinium-enhancing T1 lesion counts from the last BOLD assessment were sustained in the 10-mg, 2-mg, 1.25-mg, and 0.5-mg dose groups (0 [0-0], 0.1 [0-1.9], 0.1 [0-2.6], and 0.1 [0-2.8] at month 24, respectively). At the 3 highest vs 2 lowest doses, the estimated new/newly enlarging T2 lesion counts (95% CIs) were lower during months 6 to 12 (0.5 [0.2-1.3], 0.4 [0.2-1.1], and 0.2 [0.1-0.6] vs 1.3 [0.6-2.8] and 1.4 [0.7-2.7]), months 12 to 18 (0.4 [0.1-1.1], 0.4 [0.1-1.3], and 0.4 [0.2-1.0] vs 1.0 [0.4-2.6] and 3.6 [1.7-7.6]), and months 18 to 24 (0 [0-not estimable], 0.9 [0.1-7.6], and 0.1 [0-1.7] vs 1.6 [0.3-7.7] and 2.0 [0.4-9.5]). Annualized relapse rates (95% CIs) up to month 24 were similarly lower for the 3 highest doses: 0.22 (0.12-0.40) for 10 mg, 0.20 (0.10-0.38) for 2 mg, and 0.14 (0.08-0.26) for 1.25 mg vs 0.33 (0.19-0.56) for 0.5 mg and 0.33 (0.21-0.50) for 0.25 mg. CONCLUSIONS AND RELEVANCE: For up to 24 months of siponimod treatment, multiple sclerosis disease activity was low and there were no new safety signals; investigation in phase 3 trials is encouraged. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01185821.