rituximab + obinutuzumab

**rituximab + obinutuzumab** is a combination of two monoclonal antibodies targeting CD20, used primarily in the treatment of B-cell malignancies such as follicular lymphoma and chronic lymphocytic leukemia. **Rituximab** is a type I chimeric anti-CD20 monoclonal antibody that promotes B-cell lysis via mechanisms including antibody-dependent cellular cytotoxicity (ADCC), complement-dependent cytotoxicity (CDC), and direct apoptosis. **Obinutuzumab** is a humanized, glycoengineered type II anti-CD20 monoclonal antibody with increased ADCC (due to reduced fucose content), enhanced direct cell death induction, and altered CD20 binding compared to rituximab. This combination is not an approved, branded, or formulation drug, but both agents are sometimes sequenced or compared in clinical settings for patients who have relapsed or are refractory to the other agent. The primary indications involve treatment of follicular lymphoma, chronic lymphocytic leukemia, and other B-cell non-Hodgkin lymphomas.