Auerswald, Guenter, Khayat, Claudia Djambas, Stasyshyn, Oleksandra, Iosava, Genadi, Romashevskaya, Irina, López, Marta Julia, Seifert, Wilfried, and Rogosch, Tobias
Purpose: Formulation V (VONCENTO®) is a plasma-derived high-concentration/low-volume, high-purity von Willebrand factor (VWF)/factor VIII (FVIII) concentrate, originally indicated for von Willebrand disease (VWD) in adults and adolescents. This multicenter, open-label study (SWIFTLY-VWD) evaluated the pharmacokinetics (PK), as well as hemostatic efficacy and safety, of Formulation V in pediatric patients (< 12 years) with severe VWD requiring treatment or prophylaxis of bleedings. Methods: PK investigations were performed following one dose of Formulation V at Day 1 and 180. Nonsurgical bleeds were analyzed, while hemostatic efficacy was graded as excellent/good/moderate/none. Safety assessments included adverse events, and presence of VWF and/or FVIII inhibitors. Results: Formulation V was administered as on-demand (N=13) or prophylaxis therapy (N=4) for 12 months (< 6 years, N=9; 6 to < 12 years, N=8). PK parameters for VWF markers were generally comparable to adults but showed lower VWF:ristocetin cofactor (RCo) exposure. Incidence of major bleeds was lower for prophylaxis (3.3%) than on-demand therapy (27.1%); joint bleeds were also lower (3.3% vs 11.5%, respectively). Investigator-reported excellent/good hemostatic efficacy against nonsurgical bleeds was 100%. No clinically relevant differences in PK, hemostatic efficacy, or safety were observed between age-groups (< 6 years and 6 to < 12 years). Formulation V was well tolerated. Adverse events were mild–moderate and consistent with the adult safety profile. No cases of anaphylactic reactions or angioedema, development of FVIII/VWF inhibitors, thromboembolic events, or viral infections were reported. Conclusion: This study provides evidence for use of Formulation V to treat and prevent bleeding in pediatric patients with severe VWD, and led to the European approval of Formulation V in children. [ABSTRACT FROM AUTHOR]