chlorambucil + CD20 antibody

Chlorambucil + CD20 antibody refers to the combination of **chlorambucil**, an orally available alkylating agent, and a **CD20-targeted monoclonal antibody** (such as rituximab, ofatumumab, or obinutuzumab)[1][3][5][7]. This combination is used primarily as first-line therapy for **chronic lymphocytic leukemia (CLL)**, especially in older or less fit patients for whom fludarabine-based therapy is not suitable[1][5][7]. Chlorambucil acts as an antineoplastic agent by cross-linking DNA, thereby inhibiting cell division, while the CD20 monoclonal antibody targets and depletes B cells via mechanisms including complement-dependent cytotoxicity, antibody-dependent cell-mediated cytotoxicity, and direct induction of apoptosis[3][4][5][8]. The combination has proven efficacy in increasing response rates and progression-free survival compared to chlorambucil alone, without significant increases in toxicity for the majority of patients[1][3][5][7]. Obinutuzumab (developed by Roche), ofatumumab (developed by GlaxoSmithKline), and rituximab (developed by Roche/Biogen) have all been investigated and, in some cases, FDA-approved for use in combination with chlorambucil for CLL[5][7][8].