Abstract Number: PB0876
Meeting: ISTH 2020 Congress
Theme: Hemophilia and Rare Bleeding Disorders » Hemophilia - Clinical
Background: Antihemophilic factor (recombinant; rAHF) is indicated in patients with hemophilia A of all ages to treat and prevent bleeding.
Aims: The efficacy and safety of standard prophylaxis versus on-demand rAHF treatment were assessed in previously treated Chinese patients with severe or moderately severe hemophilia A.
Methods: This open-label, sequential, interventional, post-approval study (NCT02170402) conducted in China included patients with hemophilia A of any age with factor VIII (FVIII) levels ≤2%. Ethics committees’ approval and patient informed consent were obtained. Patients received 6 months’ on-demand rAHF treatment followed by 6 months’ rAHF standard prophylaxis (20-40 IU/kg every 48 ± 6 hours). The primary outcome measure was the percentage reduction in annualized bleeding rate (ABR) during prophylaxis versus on-demand treatment in the per-protocol analysis set (PPAS; patients who completed 6 months ± 2 weeks each of on-demand treatment and prophylaxis with ≥80% compliance to dose and frequency of prophylaxis). Secondary outcome measures included ABR by cause and location, and rAHF hemostatic efficacy, immunogenicity, and safety.
Results: Of 72 patients who received ≥1 rAHF dose, 61 were included in the PPAS. Mean total ABR for on-demand rAHF treatment was 58.3 (95% CI, 52.5-64.7; median [range], 53.9 [16.7-121.7]) versus 2.5 (95% CI, 1.5-3.7; median [range], 0.0 [0.0-22.1]) during prophylaxis, representing a mean ABR reduction of 95.9%. Similar findings in favor of prophylaxis were observed for ABR according to bleed cause and location (Table). rAHF hemostatic efficacy was rated by patients as excellent/good in 96.1% of treated bleeds. Transient low-titer FVIII inhibitors (0.6-1.7 BU) in 4 patients resolved before study end. No unexpected safety signals were observed.
Conclusions: The reduction in ABR during standard prophylaxis versus on-demand rAHF treatment in previously treated Chinese patients with severe or moderately severe hemophilia A was comparable to that described in other ethnicities.
Cause of bleed | Location of bleed | |||||
Total ABR | Spontaneous | Traumatic | Joint | Non-joint | Target joint | |
ABR for on-demand rAHF treatment period (n=61) | ||||||
Mean (SD) | 58.3 (24.5) | 35.5 (28.8) | 13.4 (14.9) | 41.4 (24.5) | 19.2 (16.5) | 18.4 (20.9) |
Median (range) | 53.9 (16.7-121.7) | 33.6 (0.0-119.7) | 8.2 (0.0-63.0) | 34.2 (4.3-117.7) | 15.0 (0.0-72.6) | 8.5 (0.0-91.3) |
ABR for prophylactic rAHF treatment period (n=61) | ||||||
Mean (SD) | 2.5 (4.5) | 0.5 (1.5) | 1.3 (2.8) | 1.9 (3.9) | 0.9 (2.4) | 0.9 (2.2) |
Median (range) | 0.0 (0.0-22.1) | 0.0 (0.0-6.7) | 0.0 (0.0-17.7) | 0.0 (0.0-22.1) | 0.0 (0.0-15.7) | 0.0 (0.0-13.3) |
Percentage reduction in mean ABR | 95.9 | 97.4 | 90.3 | 95.4 | 95.3 | 95.1 |
ABR, annualized bleeding rate; PPAS, per-protocol analysis set; rAHF, antihemophilic factor (recombinant). |
[Table. Intra-patient comparison of ABRs in the rAHF on-demand and prophylactic treatment periods (PPAS).]
To cite this abstract in AMA style:
Zhao Y, Hu Y, Jin J, Zhao X, Wang X, Wu R, Wu D, Yang R, Yang F, Hu Q, Wang J, Fang H, Engl W. Efficacy and Safety of Antihemophilic Factor (Recombinant) in Previously Treated Chinese Patients with Severe or Moderately Severe Hemophilia A: Results from a Phase 4 Study [abstract]. Res Pract Thromb Haemost. 2020; 4 (Suppl 1). https://abstracts.isth.org/abstract/efficacy-and-safety-of-antihemophilic-factor-recombinant-in-previously-treated-chinese-patients-with-severe-or-moderately-severe-hemophilia-a-results-from-a-phase-4-study/. Accessed March 21, 2024.« Back to ISTH 2020 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/efficacy-and-safety-of-antihemophilic-factor-recombinant-in-previously-treated-chinese-patients-with-severe-or-moderately-severe-hemophilia-a-results-from-a-phase-4-study/