Results in previously treated patients (PTPs) taking ALPROLIX during clinical trials
In PTPs ≥12 years in B-LONG1:
In PTPs ≤11 years in Kids B-LONG1:
Study design
- B-LONG was a phase 3 open-label study investigating the safety and efficacy of ALPROLIX in 123 adult and adolescent previously treated patients with severe hemophilia B. Study arms included: fixed-interval (weekly) (n=63), fixed-dose (interval-adjusted) (n=29), on-demand (n=27), and surgical (n=12)1,2
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Kids B-LONG was a phase 3 open-label study investigating the safety and efficacy of ALPROLIX in 30 previously treated pediatric patients aged ≤11 years with severe hemophilia B. The number of patients 1 to 5 years of age was 15, and 6 to 11 years of age was 15. All 30 patients were treated with ALPROLIX on an individualized prophylactic regimen1,3
Bleed reduction observed in real-world SHL switches4,5
Data are not from a head-to-head study. No head-to-head studies were conducted to assess the safety or efficacy of ALPROLIX compared with SHL products.
Patients who switched to ALPROLIX prophylaxis saw a reduction in ABRs regardless of prior factor IX therapy or treatment regimen4
- The median ABR with ALPROLIX prophylaxis was less than half that of patients’ prior SHL prophylaxis (4.8 vs 2; n=13)4
- 81% of patients (n=26/32) who switched to ALPROLIX prophylaxis from SHL prophylaxis were able to lengthen their dosing interval4
- The median duration on ALPROLIX was 2.7 (0.5-5) years4
- Patients who switched to ALPROLIX prophylaxis from prior SHL prophylaxis saw a ~50% reduction in weekly factor consumption (n=32)4
- Median baseline consumption was 116 IU/kg on prior SHL therapy, with a reduction to 60 IU/kg at first infusion of ALPROLIX4
Study design
- Data are from a multicenter, retrospective chart review of patients with hemophilia B (n=64) aged 2 to 78 years who had received ALPROLIX prophylaxis or on-demand treatment for ≥6 months across 6 sites in the United States4
- The median duration on ALPROLIX was 2.7 (0.5-5) years4
- Some of the data were collected while the patients were in the B-LONG, Kids B-LONG, and B-YOND studies; however, most data were collected after study termination4
Study limitations
- These data are limited by the retrospective nature of the chart review; small sample sizes; the availability, completeness, and accuracy of medical charts; and the variability of the information collected by different observers4
- Data are presented using descriptive statistics; therefore, extrapolation of results to patients outside the study population may be limited4
Severe and moderate patients who switched‡ to ALPROLIX prophylaxis saw a reduction in ABRs by 76% (from 4.5 to 1.1; n=16) and 52% (from 6.9 to 3.3; n=6), respectively 4
*Interval-adjusted prophylaxis arm for B-LONG.1
†B-YOND was an open-label extension trial that studied the long-term safety and efficacy of ALPROLIX over 5 years in 120 adult, adolescent, and pediatric patients previously treated in Kids B-LONG or B-LONG. Study arms included: fixed-interval (n=74), fixed-dose (n=36), modified prophylaxis (n=17), and on-demand (n=15).6
‡Patients could be on prior SHL prophylaxis treatment or SHL on-demand treatment before switching to ALPROLIX prophylaxis.4
INDICATION:
ABR=annualized bleed rate; IP=individualized prophylactic; OD=on-demand; SHL=standard half-life.
References: 1. ALPROLIX. Package insert. Bioverativ Therapeutics Inc; 2023. 2. Powell JS, Pasi KJ, Ragni MV, et al; B-LONG Investigators. Phase 3 study of recombinant factor IX Fc fusion protein in hemophilia B. N Engl J Med. 2013;369(24):2313-2323. 3. Fischer K, Kulkarni R, Nolan B, et al. Recombinant factor IX Fc fusion protein in children with haemophilia B (Kids B-LONG): results from a multicentre, non-randomised phase 3 study. Lancet Haematol. 2017;4(2):e75-e82. 4. Shapiro A, Chaudhury A, Wang M, et al. Real-world data demonstrate improved bleed control and extended dosing intervals for patients with haemophilia B after switching to recombinant factor IX Fc fusion protein (rFIXFc) for up to 5 years. Haemophilia. 2020;26(6):975-983. 5. Data on file. Waltham, MA; Bioverativ Therapeutics Inc. 6. Pasi KJ, Fischer K, Ragni M, et al. Long-term safety and sustained efficacy for up to 5 years of treatment with recombinant factor IX Fc fusion protein in subjects with haemophilia B: results from the B-YOND extension study. Haemophilia. 2020;26(6):e262-e271.
