This study consist of a double-blind, placebo controlled, and parallel group part with eligible patients enrolled into a 24 week Double-Blind Period, and randomized in a 1:1 ratio to receive either ofatumumab or placebo in addition to their background methotrexate treatment. Patients who complete the 24 week Double-blind Period without receiving rescue DMARD treatment will then be eligible to proceed into the 120 week Open-label Period to receive repeat treatment courses with ofatumumab. In the Open-label Period ofatumumab treatment courses will be given at individualized time intervals only if a clinical response has been achieved following the previous treatment course, and followed by a subsequent worsening in disease activity.
Patients who have completed the Open-label Period or have been withdrawn will then enter a maximum 2 year Follow-up Period, or until there B-cells return to normal or to baseline levels, whichever occurs earlier
