International nonproprietary name: Filgrastim

 Chemical name: N-L- Methionyl colony-stimulating factor (human genetically engineered); non-glycated protein consisted of 175 amino acids.

Chemical name: N-L- Methionyl colony-stimulating factor (human genetically engineered); non-glycated protein consisted of 175 amino acids.

Filgrastim is a granulocyte colony-stimulating factor (G-CSF) analog used to stimulate the proliferation and differentiation of granulocytes.^[1] It is produced by recombinant DNA technology. 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 different from G-CSF naturally made in humans.

Hematopoietic growth factor. Interacting with receptors on the surface of hematopoietic cells it regulates production and release of neutrophils from the bone marrow to the peripheral blood. Dose dependant number growth of neutrophils with normal or increased functional activity is passing for 24 hours.

Filgrastim is marketed under several brand names, including Neupogen (Amgen), Imumax(Abbott Laboratories), Grafeel (Dr. Reddy’s Laboratories), Neukine (Intas Biopharmaceuticals), Emgrast (Emcure Pharmaceuticals), Religrast (Reliance Life Sciences), Zarzio (Sandoz), Nufil (Biocon) and others.

Apricus Biosciences is currently developing and testing a product under the brand nameNupen which can deliver filgrastim through the skin to improve post-chemotherapy recovery of neutrophil counts.

Filgrastim is also used to increase the number of hematopoietic stem cells in the blood before collection by leukapheresis for use in hematopoietic stem cell transplantation.Filgrastim is used to treat neutropenia,^[2] stimulating the bone marrow to increase production of neutrophils. Causes of neutropenia include chemotherapy and bone marrow transplantation.

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.^[3] Other observed adverse effects include serious allergic reactions (including a rash over the whole body, shortness of breath, wheezing, dizziness, swelling around the mouth or eyes, fast pulse, and sweating), ruptured spleen (sometimes resulting in death), alveolar hemorrhage, acute respiratory distress syndrome, and hemoptysis.^[3] Severe sickle cell crises, in some cases resulting in death, have been associated with the use of filgrastim in patients with sickle cell disorders.^[4]

Drug interactions between filgrastim and other drugs have not been fully evaluated. Drugs which may potentiate the release of neutrophils‚ such as lithium‚ should be used with caution.

Increased hematopoietic activity of the bone marrow in response to growth factor therapy has been associated with transient positive bone imaging changes; this should be considered when interpreting bone-imaging results.^[5]

Filgrastim has not been studied in pregnant women and its effects on unborn babies is unknown. If taking filgrastim while pregnant, it is possible that traces of the drug could be found in the baby’s blood. It is not known if the drug can get into human breast milk.

1. Beveridge, R. A.; Miller, J. A.; Kales, A. N.; Binder, R. A.; Robert, N. J.; Harvey, J. H.; Windsor, K.; Gore, I. et al. (1998). “A Comparison of Efficacy of Sargramostim (Yeast-Derived RhuGM-CSF) and Filgrastim (Bacteria-Derived RhuG-CSF) in the Therapeutic Setting of Chemotherapy-Induced Myelosuppression”. Cancer Investigation 16 (6): 366–373. doi:10.3109/07357909809115775.PMID 9679526. edit
2. Crawford, J.; Glaspy, J. A.; Stoller, R. G.; Tomita, D. K.; Vincent, M. E.; McGuire, B. W.; Ozer, H. (2005). “Final Results of a Placebo-Controlled Study of Filgrastim in Small-Cell Lung Cancer: Exploration of Risk Factors for Febrile Neutropenia”. Supportive Cancer Therapy 3 (1): 36–46. doi:10.3816/SCT.2005.n.023. PMID 18632435. edit
3. Neupogen “Neupogen: Patient Information Leaflet”. Amgen. Retrieved 24 June 2013.
4.  “NEUPOGEN® Patient Guide”. Amgen. Retrieved 24 June 2013.
5.  “Neupogen”. RxList. 4 June 2012. Retrieved 23 June 2013.

• Budiono Santoso; Chris J. van Boxtel; Boxtel, Christoffel Jos van (2001). Drug benefits and risks: international textbook of clinical pharmacology. New York: Wiley. ISBN 0-471-89927-5.
• “Neupogen information”. Retrieved 20 October 2005.