Filgrastim (NeupogenÒ) is FDA-approved and commercially available for use in boosting white blood cell production in participants with low blood cell counts caused by chemotherapy (nonmyeloid malignancies, acute myeloid leukemia, and bone marrow transplantation), treating severe chronic neutropenia (SCN-low blood counts), and boosting production of hematopoietic progenitor cells in patients undergoing peripheral blood progenitor cell (PBPC) collection.