Determining the Effectiveness of earLy Intensive Versus Escalation Approaches for RRMS

Prior treatment

• Participants must never have received any of the following medications: natalizumab, alemtuzumab, ocrelizumab, rituximab, ofatumumab, cladribine, siponimod, interferon beta-1a, interferon beta-1b, pegylated interferon beta-1a, glatiramer acetate, fingolimod, teriflunomide, dimethyl fumarate, daclizumab, mitoxantrone, diroximel fumarate, ozanimod, monomethyl fumarate, ponesimod.
• Participants must have not received any of the following medications, for reasons other than MS, in the last 12 months: cyclophosphamide, azathioprine, mycophenolate mofetil, cyclosporine, methotrexate, leflunomide, laquinimod, atacicept, other monoclonal antibodies.

Other illness

• Participants with clinically relevant medical or surgical conditions that, in the opinion of the investigator, would put the subject at risk by participating in the study
• Contraindication or inability to undergo MRI with Gd due to metal or metal implants, allergy to Gd contrast, claustrophobia, pain, spasticity, or excessive movement related to tremor.
• Unwillingness or inability to comply with the requirements of this protocol including the presence of any condition (physical, mental, or social) that, in the opinion of the PI, is likely to affect the participant's ability to comply with the study protocol.

Other

• Participants with contraindications to all forms of DMT in either of the treatment arms.
• Participants unable to provide informed consent.

• Men and women aged 18 to 60 years.
• Established diagnosis of MS, as defined by the 2017 revision of McDonald Diagnostic Criteria (99).
• RRMS disease course as defined by the 2013 revisions of the MS clinical course definition (4).
• Participants must have evidence of active disease based on: one or more MS relapses within the last 18 months prior to screening visit or radiological evidence of MS activity (≥2 new T2 lesions within the last 12 months from screening \[compared to a previous recent MRI within 18 months of screening\] or ≥1 GdE demonstrated on brain or spinal cord MRI performed within the last 12 months of screening).
• Participants must be ambulatory with disease onset ≤ 5 years and treatment-naïve (i.e., no MS DMT at any time in the past).
• Participants must be eligible to receive at least one form of DMT within each treatment arm.
• EDSS at Baseline visit ≤ 6.5