Occurrence of FVIII Inhibitors in Hemophilia A Patients Following an Institutional Switch to a Third Generation B-Domain-Deleted FVIII.

In 2018, Refacto AFR, a B-domain-deleted third-generation FVIII concentrate, became our preferential product. After the introduction, the development of inhibitors was prospectively monitored; retrospectively, we sought for risk factors in the patients who developed a de-novo inhibitor. Over a period of 15 months, 4/19 adult patients with non-severe haemophilia who were treated on demand for surgery, developed high titer antibodies to FVIII after administration of Refacto AFR; 5/52 mostly severe patients on prophylaxis, developed an inhibitor (3 ≥ 0.1 BU; 1 > 0.6 BU, 1 high titre) after they switched to Refacto AFR; all were children <14 years of age and with >100 exposure days, none related to surgery or intensive treatment; all received KovaltryR before. In conclusion: inhibitors were encountered in on demand patients and previously treated prophylaxis patients; this observation might be a coincidental finding, but also risk factors like genotype and surgery and/or that Refacto AFR is more immunogenic should be considered. For the patients on prophylaxis we hypothesize that loss of tolerance by preceding KovaltryR might have contributed to inhibitor development.

[Tranexamic acid: widely applicable, few risks]. / Tranexaminezuur: breed toepasbaar, weinig risico's.

Tranexamic acid is a cheap and easy to use drug for the treatment and prevention of bleeding. In the past, its use was mainly empiric and primarily in patients with coagulation disorders. More recently, large scale randomized controlled trials have shown that tranexamic acid reduces mortality in women with postpartum hemorrhage and in victims of trauma. In a number of surgical settings, including cardiothoracic and orthopedic, tranexamic acid reduces bleeding complications. In these studies, there was no signal of increased risk of thrombosis. Tranexamic acid is also effective in reducing heavy menstrual bleeding, the prevention of bleeding after dental interventions and a number of other high-prevalence conditions. There are no data that support an increased risk of thrombosis when patients without haemostatic disorders use tranexamic acid for a longer period, but addition studies would be helpful. Finally, the topical administration of the drug for mucocutaneous nuisance bleeds deserves more attention.