As rituximab-based regimens have become standard first-line treatment in CD20 positive DLBCL, the efficacy of rituximab combined with salvage chemotherapy in the second-line setting has decreased and there is a need for new therapies in patients progressing or relapsing after first-line rituximab-based therapy. Replacement of rituximab with ofatumumab in the second-line setting, following progression/relapse after first-line rituximab-containing regimens, offers the potential to overcome relative or complete rituximab resistance and thus improve response rates, the ability to proceed to consolidative HDT/ASCT, and overall survival.