A Study of Pirtobrutinib (LY3527727 [LOXO-305]) Versus Placebo in Participants With Relapsing Multiple Sclerosis

Inclusion Criteria: * Participants must have been diagnosed with relapsing MS * Participants must have one of the following 1. at least 1 documented relapse within the previous year, or 2. at least 2 documented relapse within the previous 2 years, or 3. at least 1 active Gd-enhancing brain lesion on an MRI scan in the past 6 months prior to screening. Exclusion Criteria: * Have had a diagnosis of primary progressive MS * Have a history of another clinically significant neurological disease * Had a relapse of MS within 30 days prior to randomization.