Relapsing Forms of Multiple Sclerosis (RMS) Study of Bruton's Tyrosine Kinase (BTK) Inhibitor Tolebrutinib (SAR442168) (GEMINI 2)

Inclusion criteria : * The participant must be 18 to 55 years of age, inclusive, at the time of signing the informed consent * The participant must have been diagnosed with RMS according to the 2017 revision of the McDonald diagnostic criteria * The participant has an expanded disability status scale (EDSS) score ≤5.5 at the first Screening Visit * The participant must have at least 1 of the following prior to screening: * ≥1 documented relapse within the previous year OR * ≥2 documented relapses within the previous 2 years, OR * ≥1 documented Gd enhancing lesion on an MRI scan within the previous year * Contraceptive use by men or women should be consistent with local regulations regarding the methods of contraception for those participating in clinical studies * Male participants are eligible to participate if they agree to the following during the intervention period and until accelerated elimination procedure: * Refrain from donating sperm Plus either: * Be abstinent from heterosexual intercourse as their preferred and usual lifestyle (abstinent on a long term and persistent basis) and agree to remain abstinent OR * Must agree to use contraception/barrier as detailed below * Agree to use a male condom and should also be advised of the benefit for a female partner to use a highly effective method of contraception as a condom may break or leak when having sexual intercourse with a woman of childbearing potential (WOCBP) who is not currently pregnant \- A fem…