Real-World Data on Bleeding Patterns of Hemophilia A Patients Treated with Emicizumab.

Emicizumab (Hemlibra™) is approved for prophylaxis of hemophilia A (HA) patients. The HAVEN studies addressed bleeding reduction in emicizumab-treated patients, but real-world data on bleeding patterns during emicizumab therapy are lacking. We aimed to compare the occurrence of breakthrough bleeding at different time points, starting from emicizumab initiation. This longitudinal prospective observational cohort study included HA patients (n = 70, aged 1 month to 74.9 years) that completed at least 18 months of follow-up in our center. We analyzed the number of spontaneous and traumatic bleeds during selected time points of the study ("bleeding periods"). The percentage of traumatic and spontaneous bleeding episodes was not significantly different among "bleeding periods" (P = 0.053 and P = 0.092, respectively). Most trauma-related treated bleeds resulted from either hemarthrosis (53%) or head trauma (33%). Spontaneous bleeding episodes were mostly hemarthroses (80%). Potential associations of the patients' age, annualized bleeding rate before emicizumab treatment, and the presence of inhibitors with spontaneous bleed occurrence were analyzed with binomial logistic regression. The odds of bleeding while on emicizumab increased by a factor of 1.029 (P = 0.034) for every one year of age. Conclusions: Our real-world data revealed that the risk of bleeding persists, especially in older patients, despite therapy with emicizumab. These data may help clinicians in counselling their patients and in planning their management.

Low Concentrations of Recombinant Factor VIIa May Improve the Impaired Thrombin Generation of Glanzmann Thrombasthenia Patients.

INTRODUCTION: Glanzmann thrombasthenia (GT) is a rare bleeding disorder. The disease is caused by the lack or dysfunction of platelet membrane glycoprotein IIb/IIIa (integrin αIIbß3) which is essential for platelet aggregation. Bleeding episodes are usually managed by platelet transfusions. Recombinant activated factor VII (rFVIIa) is a common adjunct or alternative treatment option. OBJECTIVE: This article evaluates GT patients' response to increasing concentrations of rFVIIa using an ex vivo thrombin generation assay to elaborate the knowledge in which rFVIIa treats a platelet dysfunction for bleeding episodes and preoperative management. MATERIALS AND METHODS: Twenty-four GT patients in a non-bleeding state were enrolled into the study. Thrombin generation was measured in platelet-rich plasma (PRP) in the presence of 0.7 to 7.0 µg/mL rFVIIa. Clinical data of rFVIIa used to treat GT patients' bleeding episodes was collected, and patients' follow-up course was documented. RESULTS: Thrombin generation was significantly decreased in GT patients compared with controls. An individual response to rFVIIa spiking was noted in GT patients' PRP. In the majority of patients, a significant improvement in thrombin generation was already demonstrated with low concentrations (0.7 µg/mL) of rFVIIa. CONCLUSION: Thrombin generation is improved in the majority of GT patients following ex vivo spiking with rFVIIa. The magnitude of this improvement is individual and was noted at low concentrations of rFVIIa. There is a need for a prospective clinical trial to find the optimal doses or rFVIIa for treatment of GT patients.