Distribution of the recombinant coagulation factor 125I-rFVIIa in rats.

Recombinant human factor VIIa (rFVIIa; NovoSeven®) is a two-chain activated clotting factor that is used in the treatment of haemophilia. The distribution of radioactivity in male and pregnant and non-pregnant female rats has been examined by whole-body autoradiography (WBA) after single intravenous doses of 125 I-radiolabelled rFVIIa at a dosage level of ca. 0.1 mg/kg. Concentrations of radioactivity were highest in the blood and the highly perfused major thoracic and visceral organs and gonads. This distribution of radioactivity was generally similar in pregnant and non-pregnant females, and although radioactivity was concentrated in the foetal thyroid, it was present in other foetal tissues only at trace levels