Vilfaktin is for intravenous administration only!
Treatment with the drug Vilfaktin should be conducted under the supervision of a doctor with experience in the treatment of bleeding disorders.
Typically, 1 IU / kg von Willebrand factor increases the level of PV: RQo in blood plasma at 0.02 IU / ml (2%). In order to ensure hemostasis, it is usually recommended to administer 40-80 IU / kg von Willebrand factor. We should strive to achieve PV levels: RQ> 0.6 IU / ml (60%) and factor VIII:C > 0.4 IU / ml (40%), because content of the factor VIII:C, equal to 0.4 IU / ml (40%), is usually sufficient to provide hemostasis.
1. Prevention of bleeding before routine or emergency surgical interventions and treatment of bleeding (spontaneous or due to trauma).
In the case of urgent surgical interventions, the preparation of Wilfactin should be administered one hour before the beginning of the operation.
For planned surgical interventions, the preparation of Wilfactin should be administered 12-24 hours before the operation, then re-enter the drug 1 hour before the operation. In such a case, simultaneous administration of the coagulation factor VIII preparation is not required, since endogenous factor VIII:C to the beginning of the operation already reaches 0.4 IU / ml (40%). Nevertheless, each patient should determine the content of the factor VIII:C.
With the introduction of a single von Willebrand factor, the content of factor VIII: C in the blood plasma increases gradually and reaches a maximum after 6-12 hours. Administration of the preparation Vilfaktin does not lead to an immediate increase in the concentration of the factor VIII:C. Therefore, if the initial level of the factor VIIT.C in plasma is below critical, and urgent correction of hemostasis is required (for example, in cases of treatment of bleeding, severe injuries or urgent surgery), then a preparation of the factor of blood coagulation VIII should be administered simultaneously with the preparation of Wilfactin in order to achieve the activity of the factor VIII:C, providing hemostasis.
If there is no need for an urgent increase in the content of factor VIII: C (for example, in planned operations),or if the initial activity of factor VIII: C in the plasma is sufficient to provide hemostasis, the physician may decide not to use the coagulation factor VIII preparation together with the first administration of the preparation Vilfaktin.
The dose and duration of therapy depend on the clinical condition of the patient, the type and severity of bleeding and the content of von Willebrand factor.
The dosage regimen in children is calculated taking into account the body weight, that is, it is based on the same principles as in adults. The frequency of administration of the drug Vilfaktin should always depend on the clinical effectiveness in each individual case.
The first injection
For the treatment of bleeding or in severe injuries, the preparation Vilfaktin is administered in doses of 40 to 80 IU / kg in combination with the required amount of coagulation factor VIII to achieve an adequate level of activity factor VIII:C. The preparation of coagulation factor VIII is administered immediately before the operation or as soon as possible after bleeding or trauma; The dose of coagulation factor VIII is determined by its initial content in the blood plasma.
In some cases, the preparation of Wilfactin should be administered at an initial dose of 80 IU / kg, in particular in patients with type 3 von Willebrand disease,in which maintaining adequate levels of vWF can require higher doses than with other types of von Willebrand disease.
Follow-up treatment
If necessary, treatment should be continued with a suitable dose of Wilfactin 40-80 IU / kg per day, in one or two injections, for one or several days. The dose and frequency of injections should always correspond to the nature of the surgical intervention, the clinical condition of the patient, the content of PV: RV and FVIII: C in the blood plasma, and the type and severity of bleeding.
2. Prevention of spontaneous bleeding in patients with von Willebrand disease.
Vilfaktin can be used as a long-term prophylaxis in doses individually selected for each patient. The introduction of the drug Vilfaktin in doses from 40 to 60 IU / kg 2-3 times a week can reduce the number of bleeding.
Instructions for preparing a solution
Wilfactin is a lyophilizate, which is dissolved immediately before use with water for injection.
Wilfactin is administered only intravenously, as a single dose, immediately after dissolution, at a rate of no more than 4 ml per minute.
Preparation of the solution
Observe the usual rules of asepsis.
1. If necessary, bring two vials (lyophilizate and solvent) to a temperature not higher than 25 ° C.
2. Remove the plastic caps from the vials. Disinfect the surface of both plugs.
3. Remove the protective film from the adapter.
The bottle with the solvent is installed vertically, attach the blue side of the adapter to the vial and press the adapter all the way. The adapter must be securely connected to the vial.
4. Remove the protective cover from the other side of the adapter.
5. Turn the adapter connected to the solvent bottle, push it with a transparent part onto the vial with lyophilizate and secure the adapter to the stop. The solvent moves automatically into the powder vial. While holding the connected vials together, stir the solution with gentle rotational movements until the drug dissolves completely.
6. While holding the vial with a soluble drug in one hand and a bottle of solvent in the other, unscrew the blue part of the device together with the solvent bottle.
Usually the powder dissolves immediately, it must completely dissolve in less than 10 minutes. The resulting solution should be clear or slightly opalescent, colorless or pale yellow.Do not use a cloudy solution or solution containing a precipitate.
7. While holding the vial vertically with the dissolved preparation, twist the sterile syringe to the device Mix2Vial. Slowly dial the drug into the syringe.
After typing the drug into the syringe, holding it (piston down), unscrew the device Mix2Vial and replace it with an intravenous or epicranial needle.
Remove air from the syringe, and after disinfecting the skin, insert the needle into the vein.
Enter intravenously, slowly and without interruption, immediately after dissolving the drug, at a rate of no more than 4 ml / minute.
From the point of view of microbiology, the drug should be used immediately after dissolution. However, he demonstrated the physicochemical stability after 24 hours storage at a temperature of 25 ° C. Any amount of unused product or remaining material must be disposed of in accordance with existing regulations.