High dose of human plasma-derived FVIII-VWF as first-line therapy in patients affected by acquired haemophilia A and concomitant cardiovascular disease: four case reports and a literature review

Haemostatic control is the first priority in acquired haemophilia A (AHA) and recent consensus recommendations suggest using bypassing agents (BAs) (recombinant activated FVII (rFVIIa) and activated prothrombin complex concentrate) as first-line treatment of bleeds. FVIII concentrates, both plasma-derived and recombinant, may be used with low inhibitor titre, minor haemorrhagic episodes and when bypassing drugs are not available [1]. The use of BAs may be associated with thrombotic complications, especially in the elderly with cardiovascular comorbidity, and should be carried out cautiously, as a literature review reported that 7% of patients treated with rFVIIa experienced thrombotic events [2]. Efficacy of FVIII concentrates in AHA has been reported since the early 1990s. Yet the published reports are retrospective, include few patients and deal with heterogeneous populations (see Table 1). Two main protocols have been recorded in the literature [3,4], but FVIII is often used at a much lower dosage. For instance, the data provided by the EACH2 Registry [5] reporting that the efficacy of FVIII treatment is lower than using BAs would show median doses inferior to those recommended in the literature (initial mean dose 50 U kg , total mean dose for patient 20 000 U, period-treatment range 4–6 days). This letter reports on the experience of our Centre in the use of high-dose human plasma-derived FVIII-VWF (HP-FVIII-VWF) concentrates in four patients affected by AHA and concomitant cardiovascular disease treated with a standardized protocol and include a review of the literature on the usage of HP-FVIII in the treatment of AHA.