Type 3 von Willebrand disease (VWD3) is a rare and severe bleeding disorder characterized by often undetectable von Willebrand factor (VWF) plasma levels, a recessive inheritance pattern, and heterogeneous genotype. The objective of this study was to identify the VWF defects in 265 European and Iranian patients with VWD3 enrolled in 3WINTERS-IPS (Type 3 Von Willebrand International Registries Inhibitor Prospective Study). All analyses were performed in centralized laboratories. The VWF genotype was studied in 231 patients with available DNA (121 [115 families] from Europe [EU], and 110 [91 families] from Iran [IR]). Among 206 unrelated patients, 134 were homozygous (EU/IR = 57/77) and 50 were compound heterozygous (EU/IR = 43/7) for VWF variants. In 22 patients, no or only one variant was found. A total of 154 different VWF variants (EU/IR = 101/58 [5 shared]) were identified among the 379 affected alleles (EU/IR = 210/169), of which 48 (EU/IR = 18/30) were novel. The variants p.Arg1659*, p.Arg1853*, p.Arg2535*, p.Cys275Ser, and delEx1_Ex5 were found in both European and Iranian VWD3 patients. Sixty variants were identified only in a single allele (EU/IR = 50/10), whereas 18 were recurrent (≥3 patients) within 144 affected alleles. Nine large deletions and one large insertion were found. Although most variants predicted null alleles, 21% of patients carried at least 1 missense variant. VWD3 genotype was more heterogeneous in the European population than in the Iranian population, with nearly twice as many different variants. A higher number of novel variants were found in the Iranian VWD3 patients.

Prophylaxis with emicizumab, a bispecific monoclonal antibody that mimics FVIII function, has shown encouraging results in clinical trials in terms of efficacy and safety. However, current experien...

Introduction: Rare bleeding disorders (RBD) constitute 5% of total hereditary bleeding disorders, although the number could be higher, due to the presence of undiagnosed asymptomatic patients. The objective of this study was to analyze the prevalence and characteristics of patients with severe RBDs in our area.Material and methods: We analyzed the patients with RBD followed at a tertiary-level hospital between January 2014 and December 2021.Results: A total of 101 patients were analyzed, with a median age at diagnosis of 27.67 years (range 0-89), of which 52.47% were male. The most frequent RBD in our population was FVII deficiency. Regarding the diagnostic reason, the most frequent cause was a preoperative test and only 14.8% reported bleeding symptoms at the time of diagnosis. A genetic study was carried out in 63.36% of patients and the most frequent mutation type found was finding a missense mutation.Conclusions: The distribution of RBDs in our centre is similar to the one reported in the literature. The majority of RBDs were diagnosed from a preoperative test and this allowed preventive treatment prior to invasive procedures to avoid bleeding complications. 83% of patients did not have a pathological bleeding phenotype according to ISTH-BAT

Standard FIX prophylaxis for PWHB require frequent injections, which has led to the development of extended half-life products like rIX-FP (albutrepenonacog alfa) that has shown good efficacy in clinical studies. This ambispective study aims to report a real-world experience with rIX-FP in a Spanish centre with PWHB who switched from SHL-FIX or began prophylaxis with rIX-FP. Five PWHB were included in this study, Four PTP switched to rIX-FP with prophylaxis every 7 days whilst one PUP started with an every-14-days regimen. 3 PTPs extended their dosing intervals to every 14 days or every 21 days. In all PTPs, median annualized spontaneous and joint bleeding rates were maintained at 0.00 and median (range) of ABR was 0.92 (0.00-2.77) after switch to rIX-FP. Mean trough level with previous product was 3.68% (SD = 2.06), while it was 7.08% (SD = 3) with all rIX-FP dosing intervals. After switching to rIX-FP, all PTP reduced their annual infusion rate between 50 and 84% and their annual FIX consumption by 61% (59-67%). This is the first reported real-world experience with albutrepenonacog alfa in a small cohort in Spain and demonstrates good bleeding control together with a reduction of the infusion rate, factor consumption and higher through factor level than previous treatment.