Inclusion Criteria: Below are some criteria for inclusion. Additional Inclusion criteria apply. 1. Subject must understand and voluntarily sign an informed consent form (ICF) prior to any study-related assessments/procedures being conducted. 2. Subject is willing and able to adhere to the study visit schedule and other protocol requirements. 3. Subject is male or female 18 to 65 years of age (inclusive) at the time of signing of the ICF. 4. Subject has a diagnosis of MS according to the 2010 or 2017 Revised McDonald criteria. 5. Subjects has ≤ 5 years since time of RMS diagnosis. 6. Subject has ≤ 1 approved RMS DMT at time of study entry. Exclusion Criteria: Following are some criteria that would exclude the subject from participation. Additional exclusion criteria apply. Exclusions Related to General Health 1. Subject has any clinically relevant hepatic, neurological, pulmonary, ophthalmological, endocrine, psychiatric, or other major systemic disease making implementation of the protocol or interpretation of the study difficult or that would put the subject at risk by participating in the study. Subjects with mild or moderate asthma, and subjects with other mild pulmonary disease (eg, chronic obstructive pulmonary disease [COPD]) may be included in the study. 2. Subject has a presence of other neurologic disorders to explain the progressive neurologic disability (as defined in the key inclusion criteria) or that might affect cognition. 3. Subject has a visual or other sensorimotor impairment likely to confound test performance. 4. Subject has a presence of > 10 GdE lesions on the Baseline brain MRI scan. 5. Subject has a history of developmental disorder (eg, attention-deficit/hyperactivity disorder [ADHD], learning disability).