sponsor decision due to low recruitment

This clinical study compares the efficacy, safety, and tolerability of therapy with ponesimod vs placebo in subjects with active RMS who are treated with DMF (Tecfidera®).

The study will assess the efficacy, safety, and tolerability of add-on therapy with ponesimod 20 mg vs placebo in adult participants with active relapsing multiple sclerosis (RMS) who are treated with dimethyl fumarate (DMF). Approximately 600 participants who have been receiving DMF for at least 6 months will be randomized in a 1:1 ratio to ponesimod 20 mg or placebo. The study consists of the following study periods: Pre-randomization period; Treatment period; Post-treatment observation period. The study includes one ponesimod treatment arm at the maintenance dose of 20 mg o.d. corresponding to the optimal dose when used as monotherapy based on the Phase 2 dose-finding trial and its ongoing extension. The study includes a placebo comparator arm, but all patients will remain on DMF background therapy throughout the study. Moreover, participants who experience a confirmed relapse or an event of 24-week confirmed disability accumulation (DMF) while on study drug will have the option to switch to an alternative treatment. The treatment period has a variable duration from a minimum of 60 weeks (for the last subject randomized) to a maximum of 156 weeks for the first subjects randomized in the trial and includes a gradual up-titration of ponesimod from a 2 mg starting dose to a 20 mg maintenance dose over a period of 14 days. The total duration of the study will be approximately up to 167 weeks.

Inclusion Criteria:

• Signed informed consent prior to initiation of any study-mandated procedure.
• Women of childbearing potential must have a negative pregnancy test and use reliable methods of contraception
• Presenting with a diagnosis of MS as defined by the revised (2010) McDonald Diagnostic Criteria for MS with relapsing course from onset (i.e., relapsing-remitting multiple sclerosis (RRMS), or secondary progressive multiple sclerosis (SPMS) with superimposed relapses).
• Ongoing treatment with DMF for at least 6 months prior to screening
• Active disease after at least 3 months of DMF treatment
• Ambulatory and with an EDSS score between 0 and 6.0 (inclusive).

Exclusion Criteria:

• Lactating or pregnant women and women intending to become pregnant during the study.
• Presenting with a diagnosis of MS with progressive course from onset (i.e., primary progressive MS or progressive relapsing MS).
• Evidence of a relapse of MS with onset within 30 days prior to baseline EDSS assessment.
• Any circumstances or conditions, which, in the opinion of the investigator, may affect full participation in the study or compliance with the protocol.

Any study-related publication written independently by investigators must be submitted to Actelion for review at least 30 days prior to submission for publication or presentation. Upon review, Actelion may provide comments and may also request alterations and/or deletions for the sole purpose of protecting its confidential information and/or patent rights. Neither the institution nor the investigator should permit publication during such a review period.