A Study of Obexelimab in Patients With Relapsing Multiple Sclerosis (MoonStone)

Inclusion Criteria: 1. Diagnosis of RMS (relapsing-remitting or secondary progressive with relapses) according to the 2017 revision of the McDonald diagnostic criteria 2. An EDSS of ≤ 5.5 at the Screening Visit 3. Must have documentation of: 1. . at least 1 relapse within the previous year OR 2. . ≥ 2 relapses within the past 2 years OR 3. . ≥ 1 active Gd-enhancing brain lesion on an MRI scan within the past 6 months prior to screening 4. Not of childbearing potential or willing to follow contraceptive guidance Exclusion Criteria: 1. Primary progressive MS or secondary progressive MS without relapses 2. Meet criteria for neuromyelitis optica spectrum disorder 3. Relapse in the 30 days prior to randomization 4. ≥ 10 years disease duration from onset with patient's EDSS ≤ 2.0 (patient reported is adequate in absence of written medical record) 5. Has \> 20 Gd+ lesions on brain MRI at screening