cyclophosphamide + filgrastim + fludarabine

This regimen is a combination of three agents—cyclophosphamide, fludarabine, and filgrastim—used primarily in the treatment of hematologic malignancies such as chronic lymphocytic leukemia (CLL) and non-Hodgkin lymphoma (NHL). Cyclophosphamide is an alkylating agent that crosslinks DNA, leading to cell death. Fludarabine is a purine analog that inhibits DNA synthesis by interfering with DNA polymerase and ribonucleotide reductase. Filgrastim is a recombinant granulocyte colony-stimulating factor (G-CSF) that stimulates the production of neutrophils to reduce infection risk during chemotherapy-induced neutropenia. This combination has demonstrated high response rates and manageable toxicity profiles in clinical trials for CLL and NHL, with filgrastim included specifically to support white blood cell recovery following cytotoxic chemotherapy[1][9][10].