Improved coagulation and haemostasis in haemophilia with inhibitors by combinations of ^superFactor Va and Factor VIIa

Summary

Bypassing inhibitors in haemophilia patients is limited to activated (a) Factor(F)VII products. We introduced “FVa activity augmentation” as another bypassing strategy and studied effects of an engineered FVa variant designated ^superFVa. Procoagulant and clot stabilising properties of ^superFVa and recombinant human (rh)FVIIa, either alone or in combination, were studied in thrombin generation and clot lysis assays in normal human plasma (NHP) with or without anti-FVIII inhibitors, in haemophilia plasma, and in FVIII-deficient mice or in wild-type mice with anti-FVIII inhibitors. ^SuperFVa was as effective as rhFVIIa to improve thrombin generation or clot lysis. Furthermore, procoagulant effects were significantly enhanced when these compounds were combined. RhFVIIa at 40 nM (a therapeutic concentration) improved thrombin generation mildly, but markedly improved thrombin generation when combined with a low concentration (e. g. 3 nM) of ^superFVa. In clot lysis studies, the concentration of rhFVIIa to normalise clot lysis times could be reduced by 100-fold (e. g. from 40 nM to 0.4 nM) when combined with a low concentration (0.37 nM) of ^superFVa. In haemostasis studies of FVIII-deficient mice, blood loss was dose-dependently reduced by either ^superFVa or rhFVIIa. ^SuperFVa (200 U/kg) corrected mean blood loss indistinguishably from rhFVIII. Blood loss correction by rhFVIIa was greatly improved when combined with ^superFVa. Similar blood loss correction results were observed for therapies in wild-type mice after infusion with anti-FVIII inhibitors. Thus, ^superFVa may be an effective procoagulant agent in the setting of haemophilia with inhibitors and it merits further evaluation for new bypassing strategies.

Supplementary Material to this article is available online at www.thrombosis-online.com.

Keywords

Haemophilia - Factor VIII - Factor V - bleeding - haemostasis - inhibitors

^* Both authors contributed equally to this work.

• References

• 1 Berntorp E, Shapiro AD. Modern haemophilia care. Lancet 2012; 379: 1447-1456.
• 2 Gouw SC, van der Bom JG, Ljung R. et al. Factor VIII products and inhibitor development in severe haemophilia A. N Engl J Med 2013; 368: 231-239.
• 3 Laros-van Gorkom BA, Falaise C, Astermark J. Immunosuppressive agents in the treatment of inhibitors in congenital haemophilia A and B-- a systematic literature review. Eur J Haematol Suppl 2014; 76: 26-38.
• 4 Berntorp E, Astermark J, Carlborg E. Immune tolerance induction and the treatment of haemophilia. Malmo protocol update. Haematologica 2000; 85 (Suppl. 10) 48-50.
• 5 Hay CR, DiMichele DM. International Immune Tolerance Study. The principal results of the International Immune Tolerance Study: a randomized dose comparison. Blood 2012; 119: 1335-1344.
• 6 Hoots WK. Arthropathy in inhibitor patients: differences in the joint status. Semin Hematol 2008; 45 (02) (Suppl. 01) S42-S9.
• 7 Darby SC, Kan SW, Spooner RJ. et al. Mortality rates, life expectancy, and causes of death in people with haemophilia A or B in the United Kingdom who were not infected with HIV. Blood 2007; 110: 815-825.
• 8 Astermark J, Donfield SM, DiMichele DM. et al. A randomized comparison of bypassing agents in haemophilia complicated by an inhibitor: the FEIBA Novo-Seven Comparative (FENOC) Study. Blood 2007; 109: 546-551.
• 9 Astermark J, Santagostino E, Keith HW. Clinical issues in inhibitors. Haemophilia 2010; 16 (Suppl. 05) 54-60.
• 10 Broze GJJ, Higuchi DA. Coagulation-dependent inhibition of fibrinolysis: role of carboxypeptidase-U and the premature lysis of clots from haemophilic plasma. Blood 1996; 88: 3815-3823.
• 11 Foley JH, Nesheim ME. Soluble thrombomodulin partially corrects the premature lysis defect in FVIII-deficient plasma by stimulating the activation of thrombin activatable fibrinolysis inhibitor. J Thromb Haemost 2009; 7: 453-459.
• 12 Mosnier LO, Lisman T, van den Berg HM. et al. The defective down regulation of fibrinolysis in haemophilia A can be restored by increasing the TAFI plasma concentration. Thromb Haemost 2001; 86: 1035-1039.
• 13 Lisman T, Mosnier LO, Lambert T. et al. Inhibition of fibrinolysis by recombinant factor VIIa in plasma from patients with severe haemophilia A. Blood 2002; 99: 175-179.
• 14 Schlachterman A, Schuettrumpf J, Liu JH. et al. Factor V Leiden improves in vivo haemostasis in murine haemophilia models. J Thromb Haemost 2005; 3: 2730-2737.
• 15 Franchini M, Lippi G. Factor V Leiden and haemophilia. Thromb Res 2010; 125: 119-123.
• 16 Kalafatis M, Egan JO, van’t Veer C. et al. The regulation of clotting factors. Crit Rev Eukaryot Gene Expr 1997; 7: 241-280.
• 17 Bos MH, Meijerman DW, van der Zwaan C. et al. Does activated protein C-resistant factor V contribute to thrombin generation in haemophilic plasma?. J Thromb Haemost 2005; 3: 522-530.
• 18 Mann KG, Jenny RJ, Krishnaswamy S. Cofactor proteins in the assembly and expression of blood clotting enzyme complexes. Annu Rev Biochem 1988; 57: 915-956.
• 19 von Drygalski A, Cramer TJ, Bhat V. et al. Improved haemostasis in haemophilia mice by means of an engineered factor Va mutant. J Thromb Haemost 2014; 12: 363-372.
• 20 von Drygalski A, Bhat V, Gale AJ. et al. An engineered factor Va prevents bleeding induced by anticoagulant wt activated protein C. PLoS One 2014; 9: e104304.
• 21 Gale AJ, Xu X, Pellequer JL. et al. Interdomain engineered disulfide bond permitting elucidation of mechanisms of inactivation of coagulation factor Va by activated protein C. Protein Sci 2002; 11: 2091-2101.
• 22 Mesters RM, Houghten RA, Griffin JH. Identification of a sequence of human activated protein C (residues 390-404) essential for its anticoagulant activity. J Biol Chem 1991; 266: 24514-24519.
• 23 Lusher JM KC, Green D. Acquired Haemophilia. Secon Edition ed.. Princeton: Excerpta Medica, Inc.; 1995
• 24 Bajaj SP, Rapaport SI, Brown SF. Isolation and characterisation of human factor VII. Activation of factor VII by factor Xa. J Biol Chem 1981; 256: 253-259.
• 25 Barrow RT, Lollar P. Neutralisation of antifactor VIII inhibitors by recombinant porcine factor VIII. J Thromb Haemost 2006; 4: 2223-2229.
• 26 Duncan E, Collecutt M, Street A. Nijmegen-Bethesda assay to measure factor VIII inhibitors. Methods Mol Biol 2013; 992: 321-333.
• 27 Mosnier LO, Yang XV, Griffin JH. Activated protein C mutant with minimal anticoagulant activity, normal cytoprotective activity, and preservation of thrombin activable fibrinolysis inhibitor-dependent cytoprotective functions. J Biol Chem 2007; 282: 33022-33033.
• 28 Hemker HC, Giesen P, AlDieri R. et al. The calibrated automated thrombogram (CAT): a universal routine test for hyper- and hypocoagulability. Pathophysiol Haemost Thromb 2002; 32: 249-253.
• 29 Mosnier LO, Von dem Borne PAK, Meijers JCM. et al. Plasma TAFI levels influence the clot lysis time in healthy individuals in the presence of an intact pathway of coagulation. Thromb Haemost 1998; 80: 829-835.
• 30 Mosnier LO, Fernandez JA, Davis TP. et al. Influence of the 3K3A-activated protein C variant on the plasma clot lysis activity of tPA and of tPA on the variant’s anticoagulant activity. J Thromb Haemost 2013; 11: 2059-2062.
• 31 Sixma JJ, van den Berg A. The haemostatic plug in haemophilia A: a morphological study of haemostatic plug formation in bleeding time skin wounds of patients with severe haemophilia A. Br J Haematol 1984; 58: 741-753.
• 32 Mosnier LO, Bouma BN. Regulation of fibrinolysis by thrombin activatable fi-brinolysis inhibitor, an unstable carboxypeptidase B that unites the pathways of coagulation and fibrinolysis. Arterioscler Thromb Vasc Biol 2006; 26: 2445-2453.
• 33 Tranholm M, Kristensen K, Kristensen AT. et al. Improved haemostasis with superactive analogs of factor VIIa in a mouse model of haemophilia A. Blood 2003; 102: 3615-3620.
• 34 Puetz J. Optimal use of recombinant factor VIIa in the control of bleeding episodes in haemophilic patients. Drug Des Devel Ther 2010; 4: 127-137.
• 35 Martinowitz U, Livnat T, Zivelin A. et al. Concomitant infusion of low doses of rFVIIa and FEIBA in haemophilia patients with inhibitors. Haemophilia 2009; 15: 904-910.
• 36 Gringeri A, Fischer K, Karafoulidou A. et al. Sequential combined bypassing therapy is safe and effective in the treatment of unresponsive bleeding in adults and children with haemophilia and inhibitors. Haemophilia 2011; 17: 630-635.
• 37 Monroe DM, Hoffman M, Oliver JA. et al. Platelet activity of high-dose factor VIIa is independent of tissue factor. Br J Haematol 1997; 99: 542-547.
• 38 Brufatto N, Nesheim ME. The use of prothrombin(S525C) labeled with fluros-cein to directly study the inhibition of prothrombinase by antithrombin during prothrombin activation. J Biol Chem 2001; 276: 17663-17671.
• 39 Hoots WK, Ebbesen LS, Konkle BA. et al. Secondary prophylaxis with recombi-nant activated factor VII improves health-related quality of life of haemophilia patients with inhibitors. Haemophilia 2008; 14: 466-475.