EDSS is a scale for assessing neurologic impairment in participants with multiple sclerosis (MS). EDSS is based on a standard neurological examination, incorporating functional systems (visual, brainstem, pyramidal, cerebellar, sensory, bowel and bladder, and cerebral [or mental]) that are rated and then scored as a functional systems scores (FSS), and ambulation, which is scored as ambulation score. Each FSS is an ordinal clinical rating scale ranging from 0 to 5 or 6 and an ambulation score that is rated from 0 to 16. These ratings are then used in conjunction with observations, as well as information, concerning ambulation and use of assistive devices to determine the total EDSS score. Values are from 0 points (normal neurological examination) up to 10 points (death), increasing in increments of 0.5 points. Higher scores represent increased disability.

The T25FWT test is a performance measure used to assess walking speed based on a timed 25-foot walk. The participant is directed to start at one end of a clearly marked 25-foot course and is instructed to walk 25 feet as quickly and safely as possible and immediately walk back the same distance. Score for the T25FWT is the average of the two completed trials. The time taken to complete the test is measured in seconds. The longer it takes to walk, higher the score, which indicates deterioration and greater impairment. Lower times indicate better performance and greater mobility. A 20% change from baseline of the averaged T25FWT is typically considered clinically meaningful.

The 9-HPT is a performance measure used to assess upper extremity (arm and hand) function. Participants are instructed to place pegs one by one into each of nine holes arranged in a board stabilized with a plastic nonslip sheet on a solid table, and then to remove these pegs from the holes. Both the dominant and non-dominant hands are tested twice (two consecutive trials for each hand). The participants are required to complete two successful trials for each hand. The amount of time (in seconds) required to place and remove all nine pegs is recorded for each trial. More time indicates higher raw scores, which indicates deterioration. A 20% change from baseline is typically considered clinically meaningful.

The EQ-5D-5L is a self-reported health status questionnaire that consists of six questions used to calculate a health utility score for use in health economic analysis. There are two components to the EQ-5D-5L: a five-item health state profile that assesses mobility, self-care, usual activities, pain/discomfort, and anxiety/depression used to obtain an Index Utility Score, as well as a visual analogue scale (VAS) that measures health state. The VAS is designed to rate the participant's current health state on a scale from 0 to 100, where 0 represents the worst imaginable health state and 100 represents the best imaginable health state.

C-SSRS is an assessment tool used to assess lifetime suicidality of participant (at baseline) as well as any new instances of suicidality (C-SSRS since last visit). Structured interview prompts recollection of suicidal ideation, including intensity of ideation, behavior, and attempts with actual/potential lethality. Categories have binary responses (yes/no) and include Wish to be Dead; Non-specific Active Suicidal Thoughts; Active Suicidal Ideation with Any Methods (Not Plan) without Intent to Act; Active Suicidal Ideation with Some Intent to Act, without Specific Plan; Active Suicidal Ideation with Specific Plan and Intent, Preparatory Acts and Behavior; Aborted Attempt; Interrupted Attempt; Actual Attempt (non-fatal); Completed Suicide. Suicidal ideation/behavior is indicated by a "yes" answer to any of the listed categories. Score of 0 is assigned if no suicide risk is present. Score of 1 or higher indicate suicidal ideation or behavior.