Recombinant E. coli-derived tissue factor pathway inhibitor reduces coagulopathic and lethal effects in the baboon gram-negative model of septic shock.

Excessive coagulation is a typical response to the vascular injury occurring in gram negative sepsis. This study evaluated the pharmacological effects of the use of a recombinant Escherichia coli derived form of tissue factor pathway inhibitor (ala-TFPI) in a baboon model of septic shock. Several doses of ala-TFPI were administered either 30 or 120 min after the initiation of a lethal intravenous infusion of E. coli into baboons. Treatment at 30 min with either 2.7 or 7.4 mg/kg of ala-TFPI resulted in the same survival rates and attenuation of both the coagulation response and cellular injury, as measured by clinical chemistry. When administration of ala-TFPI was delayed for 120 min, a dose of ala-TFPI protein continued to provide a benefit to survival. Ala-TFPI reduced the drop in mean systemic arterial pressure compared to control baboons in addition to partially attenuating the coagulopathic response. Baboons given ala-TFPI also maintained lower levels of plasma interleukin-6 (IL-6) and thrombin-antithrombin. These results suggest that the site of action of the protein may involve the later stage components of the coagulation and inflammatory pathways.