Ofatumumab: a second generation anti-CD20 monoclonal antibody in chronic lymphocytic leukemia

The successful use of monoclonal antibodies (mAb) in the treatment of human disease has steadily been growing the last decade. Rituximab, a humanmouse chimeric anti-CD20 antibody, was the first mAb for antilymphoma therapy approved. It was introduced as monotherapy and is now commonly used in combination with chemotherapy for first and subsequent lines of therapy in follicular non-Hodgkin lymphoma (FL) and chronic lymphocytic leukemia (CLL). However, a subgroup of patients does not respond, indicating a clear unmet need to explore alternative antibodies non-cross resistant to rituximab.