Pharmacological properties : תכונות פרמקולוגיות

Pharmacodynamic Properties

5.1 Pharmacodynamic properties
Pharmacotherapeutic Group: Antihaemorrhagics: blood coagulation factor VIII. ATC code: B02BD02.
In Fanhdi®, factor VIII is presented as a complex with von Willebrand factor.
The factor VIII/von Willebrand factor complex consists of two molecules (factor VIII and von Willebrand factor) with different physiological functions.
When infused into a haemophiliac patient, factor VIII binds to von Willebrand factor in the patient's circulation.
Activated factor VIII acts as a cofactor for activated factor IX, accelerating the conversion of factor X to activated factor X. Activated factor X converts prothrombin into thrombin. Thrombin then converts fibrinogen into fibrin and a clot can be formed.
Haemophilia A is a sex-linked hereditary disorder of blood coagulation due to decreased levels of factor VIII and results in profuse bleeding into joints, muscles or internal organs, either spontaneously or as a result of accidental or surgical trauma. By replacement therapy the plasma levels of factor VIII are increased, thereby enabling a temporary correction of the factor deficiency and correction of the bleeding tendencies.
In addition to its role as a factor VIII protecting protein, von Willebrand mediates platelet adhesion to sites of vascular injury and plays a role in platelet aggregation.
There are insufficient data from clinical trials in children less than 6 years of age.
Data on Immune Tolerance Induction (ITI) have been collected in paediatric and adult patients with haemophilia A who have developed inhibitors to FVIII. The 57 patients from a retrospective study and 14 patients from prospective studies included a broad spectrum of primary and rescue ITI patients with varying prognoses for achieving immune tolerance. Data show that Fanhdi has been used to induce immune tolerance.
In patients where tolerance was achieved, bleeding could be prevented or controlled on either prophylactic or on-demand therapy with a FVIII concentrate.

Pharmacokinetic Properties

5.2 Pharmacokinetic properties
Plasma factor VIII activity decreases by a two-phase exponential decay.
The half-life of Fanhdi® obtained in the clinical trial carried out with this product is 14.18 ± 2.55 hours and the "in vivo" recovery is 105.5 ± 18.5%, which is equivalent to approximately 0.021 ± 0.004 I.U./ml per I.U./ kg administered (determinations performed following chromogenic method).