Filgrastim is a granulocyte colony-stimulating factor (G-CSF) analog used to stimulate the proliferation and differentiation of granulocytes. It is produced by recombinant DNA technology and is marketed under the trade name "Neupogen." The gene for human granulocyte colony-stimulating factor is inserted into the genetic material of Escherichia coli. The G-CSF then produced by E. coli is only slightly different from G-CSF naturally made in humans. more...
Filgrastim is used to treat neutropenia (a low number of neutrophils), stimulating the bone marrow to increase production of neutrophils. Causes of neutropenia include chemotherapy and bone marrow transplantation. Filgrastim is also used to increase the number of myeloid stem cells before collection by leukapheresis.
Filgrastim should not be used in patients with known hypersensitivity to E. coli-derived proteins.
The most commonly observed adverse effect is mild-to-moderate bone pain after repeated administration and local skin reactions at the site of injection.
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