A combination of Cyklokapron and Feiba — usually avoided due to a perceived risk of blood clots — appears to be safe and effective for treating patients with acquired hemophilia A (AHA), though these early study results need to be confirmed in clinical trials, researchers in Italy say.
The study, “Combined use of antifibrinolytics and activated prothrombin complex concentrate (aPCC) is not related to thromboembolic events in patients with acquired haemophilia A: data from FAIR Registry,” was published in the Journal of Thrombosis and Thrombolysis.
Acquired hemophilia A is a rare bleeding disorder in which the body’s immune system wrongly recognizes factor VIII (FVIII) clotting protein — essential to the wound-healing process — as a threat and produces an immune response against it. As a result, factor VIII activity is inhibited, and excessive bleeding occurs.
A rare disease, affecting an estimated 1–1.5 people per every 1 million every year, acquired hemophilia A can often be found in elderly people with other severe diseases (called comorbidities), including cardiovascular conditions, putting them at a higher risk of death.
The first-line therapy to treat bleeding episodes in these people includes activated prothrombin complex concentrate (aPCC), such as Feiba, or activated recombinant FVII. aPCC consists of a combination of clotting factors, which target different sites of the clotting cascade.
This activation of the clotting cascade may increase the risk of blood clots forming and migrating to blood vessels, where they can lodge in and obstruct blood flow — called a thromboembolic event. However, reports on the frequency of thromboembolic events in patients receiving aPCC have been inconsistent.
Antifibrinolytics, including Cyklokapron (tranexamic acid), slow the breakdown of clotting factors in the blood. While combining aPCC and antifibrinolytics increases clot stability and improves treatment effectiveness, it also increases the theoretical risk of thromboembolic events.
Since AHA patients are usually at a higher risk of cardiovascular or cerebrovascular events because they have other severe diseases, the use of this combination to treat them is still under discussion and has been done with extreme caution.
While some studies have suggested the combination is safe and effective in patients with inherited hemophilia A, similar information is lacking for those with the acquired form.
Researchers in Italy evaluated the safety and effectiveness of the Feiba-Cyklokapron combination in people with AHA by analyzing data on 56 adults (28 men and 28 women). All were registered in the Feiba on acquired hemophilia A Italian Registry (FAIR), a retrospective-prospective registry that included AHA patients treated with Feiba at 12 Italian Hemophilia Centers.
A total 101 acute bleeds were reported and treated with Feiba, of which 84.1% were spontaneous bleeding episodes, 71.3% involved muscles or skin, and 38.6% were major bleeds.
Cyklokapron was used in combination with Feiba to treat 40 (39.6%) of those bleeding episodes. Cyklokapron was administered based on clinical assessment and bleeding evaluation, with no specific established protocol concerning its use. Among the 35 patients treated with the Feiba-Cyklokapron combination, 22 had other severe diseases.
The results showed that the combination therapy was effective and well-tolerated, with no reports of thromboembolic events during treatment or follow-up. Using the combination therapy also reduced treatment duration up to a median of seven days (16.3% reduction), compared to Feiba alone, suggesting that it may indeed be more effective. Further study is necessary.
“Even though we believe antifibrinolytics could be used routinely in the treatment of patients with AHA in association with aPCC, especially in the case of severe and life-threatening bleeding, this hypothesis needs to be confirmed in adequate, larger randomized controlled clinical trials,” the researchers concluded.