Chlorambucil, is currently approved for treatment of frontline chronic lymphocytic leukemia, especially, but not limited to the ailing and elderly patient population. Several other more aggressive treatment options are available (e.g. fludarabine), however they are not suitable for all CLL patients, especially the ailing and elderly, due to greater toxicity. Ofatumumab is effective with low toxicity. The addition of ofatumumab to chlorambucil offers potentially a more effective therapy, with limited toxicity. The objective of this study was to evaluate progression-free survival (PFS), overall response and overall survival in subjects with previously untreated CLL with ofatumumab added to chlorambucil versus chlorambucil.