RecruitingPhase 1Drug trialA Study to Investigate the Safety, Tolerability, Pharmacokinetics, Immunogenicity, and Pharmacodynamics of a New Subcutaneous Formulation of Ocrelizumab in Participants With Multiple SclerosisThe main purpose of this study is to evaluate the safety and tolerability of the ocrelizumab subcutaneous (SC) test formulation in participants with multiple sclerosis (MS). The study consists of two treatment phases: a dose-escalation and dose-continuation phase. Participants will receive single ascending doses of ocrelizumab SC during an initial dose-escalation phase, with the option to continue treatment with the selected dose of ocrelizumab SC in the dose-continuation phase.