This double-blind, placebo-controlled, parallel-group study will investigate the safety and efficacy of a subcutaneous formulation of ofatumumab in the treatment of subjects with RRMS. The primary objective of the study is to investigate the efficacy as assessed by magnetic resonance imaging. Other objectives will include evaluation of tolerability/safety, dose-response relationship, pharmacokinetics, pharmacodynamics, exposure-response, as well as other clinical endpoints.