Targeting CD20 in chronic lymphocytic leukemia Myrna R Nahas, Jon E ArnasonBeth Israel Deaconess Medical Center, Boston, MA, USAAbstract: Chronic lymphocytic leukemia (CLL), the most common leukemia in adults, is standardly managed with chemotherapy in combination with the anti-CD20 antibody rituximab. In this review, we discuss the history, use, and evolution of rituximab in the treatment of CLL and explore the next generation CD20 antibodies ofatumumab and obinutuzumab with a focus on recent clinical trials. Increased understanding of the importance of B cell receptor (BCR) signaling in CLL has resulted in the development of several drugs with significant clinical activity that are ideally suited for combination with CD20 therapy as is being currently explored. Moving forward, these developments have the potential to result in treatment regimens that do not include traditional chemotherapeutic agents, which is of particular importance in CLL given the late onset of diagnosis and potential frailty of the patients.Keywords: CLL, monoclonal antibody, rituximab, ofatumumab, obinutuzumab