Inclusion Criteria:

• Participants must meet criteria for relapsing forms of multiple sclerosis, including relapsing-remitting multiple sclerosis based on the 2017 revision of the McDonald diagnostic criteria (Thompson et al. 2018) with a relapsing course (RMS) activity according to Klineova and Lublin 2018.

• Participants must have 1 of these:

  • at least 1 documented relapse within the previous year
  • at least 2 documented relapses within the previous 2 years, or
  • at least 1 active GdE brain lesion on an MRI scan in the past 180 days prior to screening.

• Have an Expanded Disability Status Scale (EDSS) score of less than or equal to (≤) 5.5 at screening and randomization.

Exclusion Criteria:

• Have had a diagnosis of:

  • primary progressive multiple sclerosis (MS) according to the 2017 revision of McDonald diagnostic criteria (Thompson et al. 2018), or
  • nonactive secondary progressive MS ( Klineova and Lublin 2018).

• Meet criteria for neuromyelitis optica spectrum disorder (Wingerchuk and Lucchinetti 2022).

• Have a history of clinically significant central nervous system (CNS) disease.

• Have had a confirmed relapse with systemic corticosteroid administration <30 days prior to randomization.

• Have more than 20 active GdE brain lesions on screening MRI scan.

• Have received any of these medications or treatments.

• Have a current or recent acute, active infection.

• Have current serious or unstable illnesses.

• Have any other clinically important abnormality at screening or baseline.