venetoclax + bendamustine + rituximab

This is a combination regimen consisting of **venetoclax** (a selective, orally administered BCL-2 inhibitor), **bendamustine** (an alkylating agent), and **rituximab** (a chimeric monoclonal antibody targeting CD20 on B lymphocytes). Venetoclax induces apoptosis in malignant B-cells by selectively inhibiting the anti-apoptotic protein BCL-2, which is often overexpressed in chronic lymphocytic leukemia (CLL). Bendamustine causes cell death via DNA crosslinking and is cytotoxic to both resting and dividing cells. Rituximab binds to CD20, leading to B-cell depletion primarily via antibody-dependent cell-mediated cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC). This drug combination has been studied in both relapsed/refractory and first-line settings in CLL. In phase 1b studies, the addition of bendamustine to venetoclax and rituximab increased toxicity without a clear benefit in efficacy compared to venetoclax + rituximab alone, but was associated with high response rates[1][3]. This regimen is not a branded product but an investigational combination therapy for CLL.