In the December 2007 issue of the Journal of Thrombosis and Haemostasis, researchers from Denmark published the results of a study on improved clot stability among hemophilia A patients when given a combination therapy of recombinant factor VIII (rFVIII) and tranexamic acid (TXA). Many hemophilia A patients not only experience slow clot formation but past studies have also shown that once formed, some clots do not last because they lack firmness.
TXA is an antifibrinolytic agent, a drug used to treat mild to moderate symptoms of bleeding, such as nosebleeds and oral bleeding during dental procedures. TXA, which can be taken in pill form or by injection, is a synthetic drug that prevents the premature breakdown of clots. It is marketed in the U.S. as Cyklokapron®, and is manufactured and distributed by the Pharmacia & Upjohn Company, a division of Pfizer, Inc.
The study was conducted at the Center for Haemophilia and Thrombosis, Department of Clinical Biochemistry at Aarhus University Hospital in Skejby, Denmark. Although the results were drawn from a small group of patients, there was notable improvement in the strength of clots following the successive adminstration of the two drugs. Eight patients with severe hemophilia A were first infused with rFVIII, followed 10 minutes later by an injection of TXA. To measure changes in clotting, blood samples were taken prior to therapy, between treatments and 10 minutes after. The level of stability was determined by maximum firmness and the size of the area under the clot’s elasticity curve. rFVIII initially enhanced maximum clot firmness threefold, while the inclusion of TXA boosted it by an additional factor of four. The area under the elasticity curve grew fivefold following rFVIII. This area grew even more dramatically, an additional 24 times, with the supplementation of TXA.
“The study demonstrates that simultaneous treatment with TXA and rFVIII significantly improves the clot stability in patients with hemophilia A,” said Anne-Mette Hvas, principal investigaror of the study, and her co-authors.
The study, “Tranexamic Acid Combined with Recombinant Factor VIII Increases Clot Resistance to Accelerated Fibrinolysis in Severe Hemophilia A,” was publsihed in the December 2007 issue of the Journal of Thrombosis and Haemostasis.
Source: Health & Medicine Week, December 24, 2007