Treatment with filgrastim should be carried out only under the supervision of an oncologist or hematologist with experience in the use of G-CSF, provided that the necessary diagnostic capabilities are available. Procedures for mobilization and apheresis of cells should be performed in an oncological or hematological center with experience in this field and the possibility of adequate monitoring of hematopoietic progenitor cells.
a) Growth of malignant cells
The safety and efficacy of filgrastim in patients with myelodysplastic syndrome and chronic myelogenous leukemia have not been established, therefore, with these diseases it is not shown. Particular attention should be paid to differential diagnosis between acute myelogenous leukemia and an imperious crisis of chronic myelogenous leukemia.
Granulocyte colony stimulating factor of a person can stimulate the growth of myeloid cells in vitro. Similar effects can be observed in vitro and for some non-myeloid cells.
b) Patients receiving cytotoxic chemotherapy
Leukocytosis: less than 5% of patients who received filgrastim in doses of more than 0.3 million units (3 μg / kg per day), the number of leukocytes increased to 100 × 109/ l and more. There are no side effects directly associated with such leukocytosis, not described. However, given the possible risk associated with high leukocytosis, during treatment with filgrastim, the number of leukocytes should be regularly determined. If after passing the expected minimum, it will exceed 50х109/ l, filgrastim should be immediately canceled. If filgrastim It is used to mobilize PSKK, it is canceled if the number of leukocytes exceeds 70x109/ l.
The risk associated with from high-dose chemotherapy:
extra care should be shown in the treatment of patients receiving high-dose chemotherapy because improvement in the outcome of malignant neoplasm has not been observed,while increased doses of chemotherapy have more pronounced toxicity, including skin reactions and side effects from the cardiovascular, nervous and respiratory systems (see instructions for the use of: specific chemotherapy drugs)
Monotherapy with filgrastim does not prevent thrombocytopenia and anemia caused by myelosuppressive chemotherapy. Because of the possibility of using higher doses of chemotherapy (eg, full doses according to the regimens), the patient may be at greater risk of thrombocytopenia and anemia. It is recommended to perform regular blood tests twice a week and determine the number of platelets and hematocrit. Particular caution should be exercised when using single-component or combined chemotherapeutic regimens capable of causing severe thrombocytopenia.
c) Patients with THC
Transformation into leukemia or pre-leukemia: special care should be taken when diagnosing severe chronic neutropenia to differentiate it from other hematologic diseases, such as aplastic anemia, myelodysplasia and myeloid leukemia.Prior to treatment should be carried out with the full blood count and determination of leukocyte platelet counts, as well as explore morphologic picture of bone marrow and karyotype. A small number (3%) of patients with severe congenital neutropenia (Costman's syndrome) who received filgrastim, myelodysplastic syndrome (MDS) and leukemia were observed. MDS and leukemia are natural complications of this disease; their connection with treatment with filgrastim is unclear. Approximately 12% of patients with initially normal cytogenetics were found to have anomalies during a second examination, including monosomy 7. If a patient with Costman's syndrome develops cytogenetic disorders, it is necessary to carefully evaluate the benefits and risk of continuing therapy with filgrastim. With the development of MDS or leukemia filgrastim should be canceled. It is not known whether long-term treatment with filgrastim predisposes patients with severe congenital neutropenia (Costman's syndrome) to the development of cytogenetic abnormalities, MDS and leukemia. Patients with Costman's syndrome are encouraged to conduct regular (approximately every 12 months) morphological and cytogenetic studies of the bone marrow.Cytogenetic disorders, leukemia and osteoporosis were detected with prolonged use of filgrastim (> 5 years) in patients (9.1%) with severe chronic neutropenia. Their connection with the drug is not clear.
Blood formula: you need to carefully control the number of platelets, especially during the first few weeks of treatment with filgrastim. In severe chronic neutropenia during the first weeks of initial therapy, a clinical blood test and platelet count are determined 2 times a week, with a stable patient condition - once a month. If the patient has thrombocytopenia (the number of platelets stably below 100x109/ l), consideration should be given to the temporary withdrawal of the drug or a reduction in the dose. There are also other changes in the blood formula that require careful monitoring, including anemia and a transient increase in the number of myeloid progenitor cells.
Other: should exclude such causes of transient neutropenia, as viral infections. The enlargement of the spleen is a direct consequence of the treatment with filgrastim. During clinical trials, 31% of patients with THC showed palpation with splenomegaly.In radiography, the increase in volume is detected soon after the start of treatment and tends to stabilize. Reducing the dose slows or stops the increase in the size of the spleen; splenectomy may be required in 3% of patients. The size of the spleen should be monitored regularly by palpation. A small number of patients had hematuria and proteinuria. To monitor these indicators, urine tests should be done regularly. Safety and efficacy of the drug in newborns and patients with autoimmune neutropenia have not been established.
d) Patients undergoing the mobilization of PMSC
After bone marrow transplantation, a blood test is performed and the platelet count is determined 3 times a week.
Mobilization: comparison of two recommended mobilization methods (only filgrastim or in combination with myelosuppressive chemotherapy) were not performed on the same contingent of patients. The choice of method of mobilization should be made depending on the overall goals of the treatment of the patient.
Prior treatment cytotoxic agents: in patients who have undergone active myelosuppressive therapy in the past,There may not be a sufficient increase in PSMC to the recommended minimum level (2,0x106 FROMD34+-cells / kg) or the acceleration of the normalization of the number thrombocytes. Some cytostatics have a particular toxicity to the precursor cells of hemopoiesis and can adversely affect their mobilization. If it is planned to transplant PSKK, it is recommended to schedule their mobilization at an early stage of treatment. Particular attention should be paid to the number of progenitor cells activated in such patients before high-dose chemotherapy. If the results of mobilization, in accordance with the above criteria, are not sufficient, alternative treatments that do not require the use of progenitor cells should be considered.
Assessment of the number ("yield") of peripheral blood stem cells: Estimating the number of PSMCs mobilized in patients with filgrastim should pay special attention to the quantification method. The results of a flow optometric analysis of the number CD34+-cells differ depending on the specific methodology, and one must be cautious about data on their number based on research,conducted in other laboratories.
There is a complex but stable statistical relationship between the number of C injected into reinfusionD34+cells and rate of normalization of the number of platelets after high-dose chemotherapy. The minimum amount of PSKK, equal to or exceeding 2.0х106 FROMD34+cells / kg, leads to a sufficient recovery of hematological indicators. The quantity exceeding this value seems to be accompanied by a faster normalization, the amount less indicated - a slower normalization of the blood picture.
e) Mobilization of PSKC in healthy donors
Procedures for mobilization and apheresis of the scrolls should be conducted in a center with experience in this area. Mobilization of PMSC is possible only if the laboratory parameters, especially the hematological parameters donor, selection criteria. Transient leukocytosis (leukocytes more than 50х109/ l) is observed in 41% of healthy donors, more than 75x109/ l - in 2% of healthy donors. Transient thrombocytopenia (number of platelets less than 100x109/ l) after the appointment of filgrastim and the conduct of leukapheresis is observed in 35% of donors. In addition, 2 cases of thrombocytopenia less than 50x109/ l after the procedure of leukapheresis. If more than one leukapheresis is required, the number of platelets must be monitored before each apheresis procedure, especially if the platelet count is less than 100x109/ l. Conducting leukapheresis is not recommended if the number of neutrophils is less than 75x109/ l, with the appointment of anticoagulants or known violations of hemostasis. Filgrastim should be canceled, or its dose should be reduced if the number of white blood cells is more than 70x109/ l. In healthy donors, it is necessary to regularly monitor all blood test parameters prior to their normalization. Given single cases of rupture of the spleen after the appointment of G-CSF to healthy donors, it is recommended to control its size (palpation, ultrasound).
There are no data on cases of violation of hemopoiesis in healthy donors up to 4 beds after the administration of filgrastim. However, in the center of apheresis, systematic monitoring of long-term safety of the drug in healthy donors is recommended.
Special instructions for recipients of allogeneic PSKK, obtained with filgrastim.
The use of an allogeneic graft Associate with an increased risk of developing an acute or chronic "graft versus host" response compared to bone marrow transplantation.
f) Neutropenia in HIV patients
In the treatment with filgrastim, a thorough blood test (absolute number of neutrophils, erythrocytes, platelets, etc.) should be performed regularly on a daily basis for the first few days, then 2 times a week for the first 2 weeks, and every week or week during a maintenance therapy. Given the fluctuations in the neutrophil count, the blood sample must be taken before the next dose is administered to determine the true maximum reduction in the number of neutrophils (nadir). In patients with infectious diseases and infiltration of the bone marrow by infectious agents (for example, the complex Mycobacterium avium) or with a bone marrow (lymphoma) tumor, filgrastim therapy is administered concomitantly with therapy directed against these conditions.
g) Other special precautions
Patients with sickle-cell anemia should regularly perform a blood test and take into account the possibility of developing splenomegaly and thrombosis of blood vessels.Patients with bone pathology and osteoporosis receiving continuous treatment with filgrastim for more than 6 months are shown to control bone density. The effect of filgrastim in patients with significantly reduced number of myeloid progenitor cells is not known. Filgrastim increases the number of neutrophils by first affecting the neutrophil precursor cells. Therefore, in patients with a reduced content of progenitor cells (for example, patients undergoing intensive radiation therapy or chemotherapy), the degree of increase in the number of neutrophils may be lower.
If a respiratory distress syndrome occurs in adults, the drug should be discontinued and prescribed appropriate treatment.