A Study of LY3541860 in Adult Participants With Relapsing Multiple Sclerosis

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.