Anti-coagulant therapy--antithrombin III

Biological properties and the efficacy of AT III concentrate for the treatment of thromboembolic disorders were evaluated in the patients with AT III deficiency. Commercially available AT III concentrates showed heterogeneity on agarose gel isoelectric focusing, however, they inhibited thrombin in the same manner. At III concentrates were infused to 11 patients with congenital AT III deficiency (4 with thrombosis). Pharmacokinetic parameters of infused AT III were calculated as follows; half time 61.1 +/- 23.0 hr. (58.4 +/- 22.6 hr. in the cases with thrombosis), max increase rate 1.01 +/- 0.3%/U/kg and recovery rate 95.4 +/- 33.3%. Simulation curves adjusted to the multiple administration were correlated well with the actually determined values in the patients and steady state concentration of AT III was achieved by the administration of this concentrate in 12 or 24 hour intervals. Clinically, substitution with AT III concentrate was proved to be effective for the treatment of thromboembolism in these patients. 16 patients with disseminated intravascular coagulation were treated with heparin (6,000 U/day) followed by AT III concentrate (1,500 U/day) administration. Clinical symptoms and laboratory findings were improved in 11 patients. From these results substitution with AT III concentrate was suggested to be beneficial for the prevention or the treatment of thromboembolic disorders in the patients with AT III deficiency.