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| Primary information |
|---|
| ID | 10464 |
| Therapeutic ID | Th1082 |
| Protein Name | Filgrastim |
| Sequence | >Th1082_Filgrastim
MTPLGPASSLPQSFLLKCLEQVRKIQGDGAALQEKLCATYKLCHPEELVLLGHSLGIPWAPLSSCPSQALQLAGCLSQLHSGLFLYQGLLQALEGISPELGPTLDTLQLDVADFATTIWQQMEELGMAPALQPTQGAMPAFASAFQRRAGGVLVASHLQSFLEVSYRVLRHLAQP
|
| Molecular Weight | 18800 |
| Chemical Formula | C845H1339N223O243S10 |
| Isoelectric Point | 5.65 |
| Hydrophobicity | 0.209 |
| Melting point | 60 |
| Half-life | Elimination half-life, healthy subjects and cancer patients, Neopogen = 3.5 hours |
| Description | 175 amino acid long, recombinant human granulocyte colony stimulating factor (G-CSF) analogue expressed and purified from a strain of E. coli. Neupogen by Amgen. Amino acid sequence is identical to the natural sequence predicted in human genome, with the exception of an N-terminal methionine to aid expression in E coli. Tbo-filgrastim, which is marketed by Sicor Biotech and FDA approved on August 29, 2012, contains the same active ingredient as Neupogen and is biologically similar, but it is formulated to be short-acting. |
| Indication/Disease | Filgrastim is used in patients with acute myeloid leukemia receiving induction or consolidation chemotherapy. It is also used in cancer patients receiving bone marrow transplant. In general, filgrastim increases neutrophil counts in order to decrease the risk of infection or duration of neutropenia in the aforementioned patient populations. Infection and neutropenia are adverse events associated with chemotherapy. Furthermore, filgrastim is also indicated for patients with severe chronic neutropenia. It mobilizes hematopoietic progenitor cells into the peripheral blood for collection by leukapheresis to allow for a more rapid engraftment. Tbo-filgrastim has a narrower indication profile than Neupogen - it is a leukocyte growth factor indicated for the reduction in the duration of severe neutropenia in patients with non-myeloid malignancies. |
| Pharmacodynamics | Used in the treatment of chemotherapy-induced neutropenia by enhancing the production of neutrophils. Filgrastim acts on hematopoietic cells by binding to specific cell surface receptors thereby stimulating proliferation, differentiation, commitment, and end cell functional activation. When tbo-filgrastim is administered to cancer patients, it took 3-5 days to reach maximum absolute neutrophil count (ANC). Levels of neutrophils returned to baseline by 21 days following completion of chemotherapy. In the healthy volunteer trials, doubling the tbo-filgrastim subcutaneous dose from 5 to 10 mcg/kg resulted in a 16-19% increase in the ANCmax and a 33-36% increase in the area under the effect curve for ANC. |
| Mechanism of Action | Filgrastim binds to the G-CSF receptor and stimulates the production of neutrophils in the bone marrow. As a G-CSF analog, it controls proliferation of committed progenitor cells and influences their maturation into mature neutrophils. Filgrastim also stimulates the release of neutrophils from bone marrow storage pools and reduces their maturation time. Filgrastim acts to increase the phagocytic activity of mature neutrophils. In patients receiving cytotoxic chemotherapy, Filgrastim can accelerate neutrophil recovery, leading to a reduction in duration of the neutropenic phase |
| Toxicity | The oral LD50 in mouse and rat was >3 mg/kg. The intravenous LD50 in rat was also >3 mg/kg.11 There is limited information regarding filgrastim overdose. The maximum tolerated dose of filgrastim has not been determined. In clinical trials of patients with cancer receiving myelosuppressive chemotherapy‚ white blood cell counts greater than 100,000/mm3 have been reported in less than 5% of patients‚ but were not associated with any reported adverse clinical effects. Patients in the bone marrow transplantation studies received up to 138 mcg/kg/day without toxic effects‚ although there was a flattening of the dose response curve above daily doses of greater than 10 mcg/kg/day |
| Metabolism | Like other G-CSF compounds, filgrastim is cleared from plasma via neutrophil-mediated clearance involving internalization via G-CSF receptors and degradation within the neutrophil. Filgrastim is also subject to extracellular proteolytic degradation by neutrophil elastase: this enzyme rapidly cleaves filgrastim and renders it inactive |
| Absorption | Filgrastim exhibits nonlinear pharmacokinetics. Subcutaneous administration of 3.45 mcg/kg and 11.5 mcg/kg of filgrastim resulted in maximum serum concentrations of 4 and 49 ng/mL‚ respectively‚ within 2 to 8 hours. Continuous 24-hour intravenous infusions of 20 mcg/kg over an 11 to 20-day period produced steady-state serum concentrations of filgrastim with no evidence of drug accumulation. The absolute bioavailability of filgrastim after subcutaneous administration is 60% to 70% |
| Vd, healthy subjects and cancer patients = 150 mL/kg |
| Clearance | Clearance rates of filgrastim were approximately 0.5 to 0.7 mL/minute/kg after intravenous administration. |
| Categories | Amino Acids, Peptides, and Proteins,Antineoplastic and Immunomodulating Agents,Biological Factors,Colony-Stimulating Factors,Glycoconjugates,Glycoproteins,Granulocyte Colony-Stimulating Factors,Hematologic Agents,Hematopoietic Cell Growth Factors,Increased Myeloid Cell Production,Leukocyte Growth Factor,Peptides,Proteins |
| Patents Number | CA1339071 |
| Date of Issue | 29-Jul-1997 |
| Date of Expiry | 29-Jul-2014 |
| Drug Interaction | NA |
| Target | Granulocyte colony-stimulating factor receptor,Neutrophil elastase |
| Brand Name | Nypozi |
| Company | NA |
| Brand Description | NA |
| Prescribed For | NA |
| Chemical Name | NA |
| Formulation | NA |
| Physical Appearance | NA |
| Route of Administration | NA |
| Recommended Dosage | NA |
| Contraindication | NA |
| Side Effects | NA |
| Useful Link 1 | NA |
| Useful Link 2 | NA |
| Remarks | NA |