LABELED FACTOR-IX KINETICS IN PATIENTS WITH HEMOPHILIA-B

  • 1 January 1981
    • journal article
    • research article
    • Vol. 58  (3) , 625-629
Abstract
Labeled factor IX was infused 5 times into 4 patients with hemophilia B. Ten-minute plasma recovery averaged 35% (SD .+-. 2) and the mean T1/2 .beta.-phase [plasma half-life] elimination was 23 h (.+-. 5). No alteration in the postinfusion 125I-factor-IX could be detected by radioautography of plasma samples run on polyacrylamide gels or on crossed-immunoelectrophoresis. Label was excreted into the urine as free 125l-iodide. Kinetics were similar when the labeled preparation was infused alone or with a commerical concentrate containing unlabeled factor IX. Infusion of factor IX in man is best described by a 2-compartment open pharmacokinetic model where factor IX is distributed in a space larger than the plasma volume.