| E.1 Medical condition or disease under investigation | 
| E.1.1 | Medical condition(s) being investigated  | 
| Relapsing Multiple Sclerosis | 
 
 
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| E.1.1.1 | Medical condition in easily understood language  | 
| Relapsing Multiple Sclerosis | 
 
 
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| E.1.1.2 | Therapeutic area  | Diseases [C] - Nervous System Diseases [C10] | 
| MedDRA Classification | 
| E.1.3 | Condition being studied is a rare disease  |  No  | 
| E.2 Objective of the trial | 
| E.2.1 | Main objective of the trial  | 
| To determine the efficacy of SAR442168 in reducing the number of new brain lesions reported in Magnetic Resonance Imaging (MRI) | 
 
 
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| E.2.2 | Secondary objectives of the trial  | 
- To evaluate the efficacy of SAR442168 on clinical symptoms and imaging measures
 - To evaluate the safety and tolerability of SAR442168 | 
 
 
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| E.2.3 | Trial contains a sub-study  |  No  | 
| E.3 | Principal inclusion criteria  | 
- Participant must be 18 to 55 years of age, inclusive, at the time of signing the informed consent.
 - Participant must have been diagnosed with relapsing multiple sclerosis (RMS) according to the 2017 revision of the McDonald diagnostic criteria.
 - Participant must have at least 1 documented relapse within the previous year, ≥2 documented relapses within the previous 2 years, or ≥1 active Gadolinium (Gd)-enhancing brain lesion on an magnetic resonance imaging (MRI) scan in the past 6 months and prior to screening.
 - A female participant must use a double contraception method including a highly effective method of birth control, except if she has undergone sterilization at least 3 months earlier or is postmenopausal.
 - Male participants, whose partners are of childbearing potential (including breastfeeding women), must accept to use, during sexual intercourse, a double contraceptive method according to the following algorithm: (condom) plus (intrauterine device or hormonal contraceptive) from inclusion up to 3 months after the last dose.
 - Male participants whose partners are pregnant must use, during sexual intercourse, a condom from inclusion up to 3 months after the last dose.
 - Male participants must have agreed not to donate sperm from the inclusion up to 3 months after the last dose.
 - Participant must have given written informed consent prior to undertaking any study-related procedure. | 
 
 
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| E.4 | Principal exclusion criteria | 
- The participant has been diagnosed with primary progressive multiple sclerosis (PPMS) according to the 2017 revision of the McDonald diagnostic criteria or with non relapsing secondary progressive multiple sclerosis (SPMS).
 - Requirement for concomitant treatment that could bias the primary evaluation.
 - Contraindication for MRI.
 - Contraindications to use MRI Gd contrast-enhancing preparations.
 - History of infection with the human immunodeficiency virus (HIV).
 - History of active or latent tuberculosis.
 - Any other active infections that would adversely affect participation or investigational medicinal product (IMP) administration in this study, as judged by the Investigator.
 - Presence of any screening laboratory or ECG values outside normal limits that are considered in the Investigator’s judgment to be clinically significant.
 - Presence of liver injury.
 - At screening, the participant is positive for hepatitis B surface antigen and/or hepatitis B core antibody and/or is positive for hepatitis C antibody.
 - Bleeding disorder or known platelet dysfunction at any time prior to screening visit.
 - Participant has received any live (attenuated) vaccine (including but not limited to varicella zoster, oral polio, and nasal influenza) within 2 months before first treatment visit.
 - Participant is receiving strong inducers or inhibitors of CYP3A or CYP2C8 hepatic enzymes.
 - Participant is receiving anticoagulant/antiplatelet therapies.
 - Participant has taken other investigational drugs within 3 months or 5 half lives, whichever is longer, before screening visit.
 - Participant has an Expanded Disability Status Scale (EDSS) score >5.5 at screening visit.
 - Participant has had a relapse in the 30 days prior to randomization.
 - Participant is pregnant or a breastfeeding woman.
 - History or presence of significant other concomitant illness.
 - The participant has received medications/treatments for MS within a specified time frame. | 
 
 
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| E.5 End points | 
| E.5.1 | Primary end point(s) | 
| Number of new Gd-enhancing T1 hyperintense lesions : Number of new Gd-enhancing T1 hyperintense lesions at the end of 12 weeks of SAR442168 treatment as detected by brain MRI | 
 
 
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| E.5.1.1 | Timepoint(s) of evaluation of this end point | 
| Week 12 for Arms 1-4, Week 4 and Week 16 for Arms 5-8 | 
 
 
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| E.5.2 | Secondary end point(s) | 
1 - Number of new or enlarging T2 lesions : Number of new or enlarging T2 lesions at the end of 12 weeks of SAR442168 treatment
 2 - Total number of Gd-enhancing T1 hyperintense lesions : Total number of Gd-enhancing T1-hyperintense lesions at the end of 12 weeks of SAR442168 treatment
 3 - Adverse events : Number (n) and percentage (%) of participants experiencing an adverse event (AE)/Serious
 Adverse Event (SAE) or potentially clinically significant abnormalities in laboratory tests, electrocardiogram (ECG), or vital signs | 
 
 
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| E.5.2.1 | Timepoint(s) of evaluation of this end point | 
1, 2 : Week 12 for Arms 1-4, Week 4 and Week 16 for Arms 5-8
 3 : From baseline to the end of study (approximately 20 weeks) | 
 
 
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| E.6 and E.7 Scope of the trial | 
| E.6 | Scope of the trial | 
| E.6.1 | Diagnosis |  No  | 
| E.6.2 | Prophylaxis |  No  | 
| E.6.3 | Therapy |  No  | 
| E.6.4 | Safety |  Yes  | 
| E.6.5 | Efficacy |  Yes  | 
| E.6.6 | Pharmacokinetic |  Yes  | 
| E.6.7 | Pharmacodynamic |  Yes  | 
| E.6.8 | Bioequivalence |  No  | 
| E.6.9 | Dose response |  Yes  | 
| E.6.10 | Pharmacogenetic |  Yes  | 
| E.6.11 | Pharmacogenomic |  No  | 
| E.6.12 | Pharmacoeconomic |  No  | 
| E.6.13 | Others |  No  | 
| E.7 | Trial type and phase | 
| E.7.1 | Human pharmacology (Phase I) |  No  | 
| E.7.1.1 | First administration to humans |  No  | 
| E.7.1.2 | Bioequivalence study |  No  | 
| E.7.1.3 | Other |  No  | 
| E.7.1.3.1 | Other trial type description |  | 
| E.7.2 | Therapeutic exploratory (Phase II) |  Yes  | 
| E.7.3 | Therapeutic confirmatory (Phase III) |  No  | 
| E.7.4 | Therapeutic use (Phase IV) |  No  | 
| E.8 Design of the trial | 
| E.8.1 | Controlled |  Yes  | 
| E.8.1.1 | Randomised |  Yes  | 
| E.8.1.2 | Open |  No  | 
| E.8.1.3 | Single blind |  No  | 
| E.8.1.4 | Double blind  |  Yes  | 
| E.8.1.5 | Parallel group |  No  | 
| E.8.1.6 | Cross over  |  Yes  | 
| E.8.1.7 | Other |  No  | 
| E.8.2 |  Comparator of controlled trial | 
| E.8.2.1 | Other medicinal product(s) |  No  | 
| E.8.2.2 | Placebo  |  Yes  | 
| E.8.2.3 | Other |  No  | 
| E.8.2.4 | Number of treatment arms in the trial | 8 | 
| E.8.3 | 
                                The trial involves single site in the Member State concerned
                             |  No  | 
| E.8.4 |  The trial involves multiple sites in the Member State concerned  |  Yes  | 
| E.8.4.1 | Number of sites anticipated in Member State concerned | 2 | 
| E.8.5 | The trial involves multiple Member States |  Yes  | 
| E.8.5.1 | Number of sites anticipated in the EEA | 27 | 
| E.8.6 Trial involving sites outside the EEA | 
| E.8.6.1 | Trial being conducted both within and outside the EEA |  Yes  | 
| E.8.6.2 | Trial being conducted completely outside of the EEA |  No  | 
| E.8.6.3 | If E.8.6.1 or E.8.6.2 are Yes, specify the regions in which trial sites are planned | 
| Canada | 
 
| Czech Republic | 
 
| Estonia | 
 
| France | 
 
| Netherlands | 
 
| Norway | 
 
| Russian Federation | 
 
| Slovakia | 
 
| Spain | 
 
| Sweden | 
 
| Ukraine | 
 
| United States | 
 
 
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| E.8.7 | Trial has a data monitoring committee |  Yes  | 
| E.8.8 | 
                        Definition of the end of the trial and justification where it is not the last
                        visit of the last subject undergoing the trial
                     | 
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| E.8.9 Initial estimate of the duration of the trial | 
| E.8.9.1 | In the Member State concerned years |  | 
| E.8.9.1 | In the Member State concerned months | 10 | 
| E.8.9.1 | In the Member State concerned days |  | 
| E.8.9.2 | In all countries concerned by the trial months | 10 |