Study to Assess the Efficacy and Safety of Ublituximab in Participants With Relapsing Forms of Multiple Sclerosis (RMS) ( ULTIMATE 1 )

Percentage of Participants With Impaired Symbol Digit Modalities Test (SDMT)

The SDMT involves a simple substitution task using a reference key, the examinee has 90 seconds to pair specific numbers with given geometric figures. Responses are done verbally. The administration time is approximately 5 minutes. The total SDMT score for each visit ranging from 0-110 is defined as the total number of correct answers reported in the case report form (CRF), where high scores indicate better outcome. Impaired SDMT is defined as a decrease from baseline of at least 4 points at any post-baseline assessment up to the Week 96 visit.

Time frame: Baseline up to Week 96

Percent Change From Baseline in Brain Volume

Time frame: Baseline up to Week 96

Percentage of Participants With Treatment Emergent Adverse Events (TEAEs) and Treatment Emergent Serious Adverse Events (TESAEs)

An adverse event (AE) is any unfavorable and unintended sign (including an abnormal laboratory finding, for example), symptom, or disease temporarily associated with the use of a medicinal product, whether or not considered related to the medicinal product. A Serious AE is defined as any untoward medical occurrence that: results in death, is immediately life-threatening, requires in-patient hospitalization or prolongation of existing hospitalization, results in persistent or significant disability/incapacity, and/or causes a congenital anomaly/birth defect. A TEAE is an AE that starts or worsens after receiving study drug.

Time frame: From the first dose of study drug through the end of the study (up to approximately 116 weeks)