Chemoimmunotherapeutic regimens using the anti-CD20 antibody rituximab improved significantly the survival rates in various B-cell lymphoproliferative disorders (LPDs), including chronic lymphocytic leukemia (CLL). The next-generation CD20 antibody obinutuzumab represents an addition to the drug armamentarium used for the therapeutic management of patients with LPDs. Areas covered: Herein, the authors discuss the biochemical and conformational engineering of obinutuzumab to increase antibody-dependent cell-mediated cytotoxicity and direct cell death. They also describe the available preclinical data on obinutuzumab's role in B-cell LPDs. Furthermore, the authors summarize the Phase I and II clinical trials of obinutuzumab, focusing on the main pharmacokinetic/pharmacodynamic characteristics, the most common clinically significant adverse events, dose optimization, and clinical outcomes of patients with CLL and other B-cell LPDs treated with obinutuzumab as monotherapy or in combination with other agents. To put these data in perspective, the use of obinutuzumab is compared with that of rituximab in CLL and other B-cell LPDs. Expert opinion: Clinical trials have demonstrated that obinutuzumab is well tolerated. The novel mechanism of action of obinutuzumab is associated with significant efficacy in CLL and other B-cell LPDs. Ongoing clinical trials are expected to determine the optimal use of obinutuzumab in these diseases.
Keywords: CD20; Monoclonal antibody; chronic lymphocytic leukemia; obinutuzumab; rituximab.