rituximab + mitoxantrone + fludarabine + dexamethasone

This is a **four-drug combination regimen** used in the treatment of **indolent B-cell non-Hodgkin lymphoma**, typically in advanced-stage disease. The regimen consists of: - **Rituximab:** A chimeric monoclonal antibody targeting CD20 on B lymphocytes, mediating cell lysis via immune mechanisms. - **Mitoxantrone:** A synthetic anthracenedione with cytotoxic and immunosuppressive properties, acting as a DNA intercalator, inhibiting DNA and RNA synthesis, and topoisomerase II. - **Fludarabine:** A purine analog that inhibits DNA synthesis by interfering with DNA polymerase, ribonucleotide reductase, and DNA primase, leading to apoptosis, especially in lymphocytes. - **Dexamethasone:** A synthetic glucocorticoid with potent anti-inflammatory and immunosuppressive effects. This combination (sometimes called RFND or R-FND) has demonstrated high efficacy (complete response rates over 89–93%) and durable remissions in clinical trials, with the principal toxicities being hematologic (notably neutropenia), and is typically administered by intravenous infusion in defined cycles. It is not a brand-named product but a protocol-based combination[1][2].