Neutromax Mechanism of Action

Pharmacology: Pharmacodynamics: Human granulocyte colony stimulating factor is a glycoprotein which regulates the production and release of functional neutrophils from the bone marrow.
NEUTROMAX containing r-Met-hu-G-CSF, causes considerable increases in peripheral blood neutrophil counts within twenty four hours of administration, with minor increases in monocytes. Effects on neutrophil counts are dose-dependent. Neutrophils produced by the human body in response to NEUTROMAX show normal or even enhanced function, as demonstrated by tests of chemotactic and phagocytic function: Following discontinuation of NEUTROMAX therapy, circulating neutrophil counts decrease by 50% within 1 to 2 days, and returns to baseline levels within 1 to 7 days. Treatment with NEUTROMAX leads to significant reductions in the incidence, severity and duration of neutropenia and febrile neutropenia frequently observed in patients undergoing cytotoxic chemotherapy. Patients treated with NEUTROMAX and cytotoxic chemotherapy require fewer and shorter hospitalization and decreased antibiotic usage compared to patients treated with cytotoxic chemotherapy alone.
Pharmacokinetics: There is a positive linear correlation between the dose and the serum concentration of r-Met-hu-G-CSF, whether administered intravenously or subcutaneously. After a single dose of Filgrastim in the range of 1.7 to 69.0 µg/kg (short i.v. infusion over 30 minutes), peak levels of r-Met-hu-G-CSF in the range of 5-1840 ng/mL were found.
Following s.c. administration of recommended doses, peak serum concentrations up to 118 ng/mL were maintained above 10 ng/mL for 8 to 16 hours. The volume of distribution in blood is approximately of 150 mL/kg.
Clearance of r-Met-hu-G-CSF has been shown to follow first-order pharmacokinetics after both subcutaneous and intravenous administration. The mean serum elimination half-life of r-Met-hu-G-CSF is approximately 3.5 hours, with a clearance rate of approximately 0.6 mL/min/kg. Continuous infusion with NEUTROMAX over a period of up to 28 days, in patients recovering from autologous bone-marrow transplantation, showed no evidence of drug accumula­tion. Mean serum clearance half-life is also similar in this case.