Local application of recombinant active-site inhibited human clotting factor VIIa reduces thrombus weight and improves patency in a rabbit venous thrombosis model

Objective:To study whether locally administered recombinant inactivated human coagulation factor VIIa (FFR-rFVIIa) would reduce the thrombus formation and improve patency in an experimental venous thrombosis model without inducing systemic changes in the coagulation.Design:Experimental double-dummy randomised study.Materials:In 20 healthy New Zealand White rabbits both jugular veins were exposed under general anaesthesia.Methods:The thrombi were induced in a 10 mm long jugular vein segment with a combination of chemical destruction of the intima and a restriction of the bloodflow. Each segment was treated with either FFR-rFVIIa or placebo injected directly into the vein.Results:1.5 mg topically applied FFR-rFVIIa significantly reduced the thrombus weight (p<0.001). The 30 and the 120 min patency tests were significantly improved (p<0.05 and p