Abstract Number: PB0971
Meeting: ISTH 2020 Congress
Theme: Hemophilia and Rare Bleeding Disorders » Hemophilia - Clinical
Background: rFVIIIFc has proven to be safe and effective in patients with severe hemophilia A. We present the largest cohort of Spanish PTPs switched to rFVIIIFc.
Aims: To determine the annualized bleeding rate (ABR) and factor consumption associated with the use of rFVIIIFc compared to previous replacement FVIII preplacement therapy, both in prophylaxis and on-demand regimens.
Methods: A single-center, observational retrospective study conducted in Vall d´Hebron Hospital from Jan 1, 2017 to Dec 31, 2019. PTPs with severe hemophilia A switched from FVIII concentrates to rFVIIIFc were included. ABRs were compared using Poisson distribution test and the number of bleeding events using a negative binomial distribution model. Factor consumption was compared using Wilcoxon test
Results: The analysis included 51 patients. The mean age was 35.3±15.4. The mean time of exposure was similar between the two arms: 18.7 months to previous FVIII product and 17.3 months to rFVIIIFc. 81% patients were on a prophylactic regimen both with previous FVIII product and rFVIIIFc.
There was a 55% reduction (95%CI 31-70%; p< 0.001) in the mean number of bleeding events and a reduction in mean ABR of 55% (95%CI 29-71%; p< 0.001) with rFVIIIFc compared to prior FVIII product.
Mean number of spontaneous bleeding events and spontaneous ABR presented a reduction of 58% (95%CI 26-76%; p= 0.003) and 56% (95%CI 18-77%; p= 0.011) respectively.
The monthly factor consumption was significantly lower with rFVIIIFc (12840- 21400UI; p= 0.0305).
The subgroup of patients on a prophylactic regimen with rFVIIIFc (n=40) showed a 52% reduction (95%CI 30-75%; p=0.001) in the number of bleeding events and a 51% reduction (95%CI 23-69%; p=0.002) in mean ABR.
Conclusions: In this cohort the number of bleeding episodes and ABR with rFVIIIFc was significantly lower compared to prior FVIII products, regardless of the treatment regimen (prophylaxis/on-demand). Monthly factor consumption was also significantly reduced.
To cite this abstract in AMA style:
Benítez O, Suito M, Cabirta A, Juarez JC, Martinez MF, Robayo G, Alvarez E, Fernandez C, Soto N, Cardona R, Gironella M. The Impact of Switching Previously Treated Patients (PTPs) to Recombinant Factor VIII Fc Fusion Protein (rFVIIIFc) in Reducing the Annualized Bleeding Rate (ABR): A Single Center Experience [abstract]. Res Pract Thromb Haemost. 2020; 4 (Suppl 1). https://abstracts.isth.org/abstract/the-impact-of-switching-previously-treated-patients-ptps-to-recombinant-factor-viii-fc-fusion-protein-rfviiifc-in-reducing-the-annualized-bleeding-rate-abr-a-single-center-experience/. Accessed September 24, 2023.« Back to ISTH 2020 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/the-impact-of-switching-previously-treated-patients-ptps-to-recombinant-factor-viii-fc-fusion-protein-rfviiifc-in-reducing-the-annualized-bleeding-rate-abr-a-single-center-experience/