Woundstat™ Topical Hemostat Reverses Clotting Diatheses in Models of Acquired and Congenital Hemophilia.

Globally over 200,000 persons are afflicted with hemophilia. Topical treatments for perioperative intervention of hemophiliac bleeding are currently limited to fibrin glues, which have been used successfully to carry out dental extractions, orthopedic and non-orthopedic surgeries, and for circumcisions. Drawbacks of fibrin glues include risk of blood borne pathogen contamination and immunologic cross-reaction to factors II and V. Although topical hemostatic agents are available for treating traumatic bleeding in the field by military and EMS first responders, their effectiveness for treating bleeding in hemophilia, platelet disorders, surgery; and for other hemostatic defects observed in cirrhosis and other liver diseases and during anticoagulation therapy overdose, have not been studied. A new granular smectite hemostatic agent (WoundStat™ [WS]) has demonstrated 100% efficacy in producing hemostasis during high pressure traumatic arterial bleeding (Ward et al., J Trauma, 63:276–284, 2007; Carraway et al., Resuscitation, 78:230–235, 2008) and has been cleared for external use in cases of moderate to severe bleeds. Here, we evaluated the effectiveness of WS in models of acquired and congenital hemophilia using a modified whole blood recalcified clotting time assay on the Actalyke Mini II activated clotting time (ACT) analyzer and empty G-ACT tubes devoid of contact phase activating reagents. Whole citrated blood recalcified to 10 mM with CaCl 2 yielded clot times (CT) of 220 s, 210 s, and 230 s, respectively, for three normal donors. Acquired hemophilia A and B bloods were prepared by incubating normal citrated blood from an individual subject with function-blocking affinity purified polyclonal antibodies to factors VIII and IX, respectively. At near saturation, antibody to FIX (150 μg/ml) increased clotting times from 213 ±3 s to 405±11 s, while antibodies to FVIII (50 μg/ml) increased CT from 229 ± 6 s to 436 ± 17 s. Matched antibody controls to prothrombin fragment 1+2 (200 μg/ml) did not prolong baseline clot time (242 ± 5 s). Addition of WS at 1 mg/ml, shortened the prolonged clotting times of the acquired hemophilia bloods from 436 ± 17 sec to 223 ±2 sec (p −4 ) and from 405 ±11 s to 204 ± 5 s (p −4 ) for the hemophilia A and B bloods, respectively. Notably no differences were observed between CT of normal blood relative to acquired hemophilia bloods treated with WS (p