Efficacy of rfixfc versus rix-fp for the treatment of patients with hemophilia b : Matching-adjusted indirect comparison of b-long and prolong-9fp trials
(2021) In Journal of Blood Medicine 12. p.613-621- Abstract
Purpose: In patients with hemophilia B, treatment with extended half-life (EHL) recombi-nant factor IX allows for longer dosing intervals while providing equal or superior bleeding protection compared with standard half-life products. This enables flexible, individualized treatment schedules, which reduce the burden of prophylaxis and improve patient outcomes. This analysis compared the efficacy of recombinant factor IX Fc fusion protein (rFIXFc) and recombinant factor IX albumin fusion protein (rIX-FP), two EHL therapies approved for prophylaxis and treatment of bleeding in hemophilia B. Patients and Methods: Matching-adjusted indirect treatment comparison (MAIC) was used to adjust the between-treatment differences in baseline... (More)
Purpose: In patients with hemophilia B, treatment with extended half-life (EHL) recombi-nant factor IX allows for longer dosing intervals while providing equal or superior bleeding protection compared with standard half-life products. This enables flexible, individualized treatment schedules, which reduce the burden of prophylaxis and improve patient outcomes. This analysis compared the efficacy of recombinant factor IX Fc fusion protein (rFIXFc) and recombinant factor IX albumin fusion protein (rIX-FP), two EHL therapies approved for prophylaxis and treatment of bleeding in hemophilia B. Patients and Methods: Matching-adjusted indirect treatment comparison (MAIC) was used to adjust the between-treatment differences in baseline characteristics. Individual patient data for rFIXFc (B-LONG) were matched to aggregated data for rIX-FP (PROLONG-9FP) followed by statistical comparison for estimated annualized bleeding rate (ABR) using a Poisson regression model with adjustment for over dispersion. Data were analyzed according to treatment regimen prior to study entry: prior prophylaxis (rFIXFc, n=48; rIX-FP, n=40) or prior episodic treatment (n=43 and n=19, respectively). Relative treatment effects are presented as incidence rate ratios (IRR) with 95% confidence intervals (CI). Results: After adjustment for baseline characteristics, estimated ABR observed for rFIXFc and rIX-FP was not significantly different in patients on prior prophylaxis (1.87 versus 1.58; IRR 1.18, 95% CI 0.67–2.10) or prior episodic (2.25 versus 2.22; IRR 1.01 95% CI 0.40–2.57) regimens. Conclusion: This MAIC analysis shows that the estimated ABR for rFIXFc-treated patients from B-LONG was similar to that of rIX-FP-treated patients from PROLONG-9FP and, therefore, indicates that the two EHL therapies provide similar efficacy when used as prophylaxis for patients with hemophilia B. Trough levels differ between the two products (1–3% [targeted] versus 20% [observed], respectively), suggesting that trough level is not a surrogate indicator when ABR is used as a criterion for clinical efficacy when comparing these FIX products in hemophilia B.
(Less)
- author
- Astermark, Jan LU ; Wojciechowski, Piotr ; Aballéa, Samuel ; Hakimi, Zalmai ; Nazir, Jameel and Klamroth, Robert
- organization
- publishing date
- 2021
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Annualized bleeding rate, Comparative effectiveness research, Factor IX deficiency, Factor IX Fc fusion protein, RIX-FP fusion protein, Treatment outcome
- in
- Journal of Blood Medicine
- volume
- 12
- pages
- 9 pages
- publisher
- Dove Medical Press Ltd.
- external identifiers
-
- scopus:85111336976
- pmid:34285621
- ISSN
- 1179-2736
- DOI
- 10.2147/JBM.S312885
- language
- English
- LU publication?
- yes
- id
- 9e071493-3702-4e97-949f-5c0136cbc83b
- date added to LUP
- 2021-09-01 13:37:30
- date last changed
- 2024-08-10 20:16:33
@article{9e071493-3702-4e97-949f-5c0136cbc83b,
abstract = {{<p>Purpose: In patients with hemophilia B, treatment with extended half-life (EHL) recombi-nant factor IX allows for longer dosing intervals while providing equal or superior bleeding protection compared with standard half-life products. This enables flexible, individualized treatment schedules, which reduce the burden of prophylaxis and improve patient outcomes. This analysis compared the efficacy of recombinant factor IX Fc fusion protein (rFIXFc) and recombinant factor IX albumin fusion protein (rIX-FP), two EHL therapies approved for prophylaxis and treatment of bleeding in hemophilia B. Patients and Methods: Matching-adjusted indirect treatment comparison (MAIC) was used to adjust the between-treatment differences in baseline characteristics. Individual patient data for rFIXFc (B-LONG) were matched to aggregated data for rIX-FP (PROLONG-9FP) followed by statistical comparison for estimated annualized bleeding rate (ABR) using a Poisson regression model with adjustment for over dispersion. Data were analyzed according to treatment regimen prior to study entry: prior prophylaxis (rFIXFc, n=48; rIX-FP, n=40) or prior episodic treatment (n=43 and n=19, respectively). Relative treatment effects are presented as incidence rate ratios (IRR) with 95% confidence intervals (CI). Results: After adjustment for baseline characteristics, estimated ABR observed for rFIXFc and rIX-FP was not significantly different in patients on prior prophylaxis (1.87 versus 1.58; IRR 1.18, 95% CI 0.67–2.10) or prior episodic (2.25 versus 2.22; IRR 1.01 95% CI 0.40–2.57) regimens. Conclusion: This MAIC analysis shows that the estimated ABR for rFIXFc-treated patients from B-LONG was similar to that of rIX-FP-treated patients from PROLONG-9FP and, therefore, indicates that the two EHL therapies provide similar efficacy when used as prophylaxis for patients with hemophilia B. Trough levels differ between the two products (1–3% [targeted] versus 20% [observed], respectively), suggesting that trough level is not a surrogate indicator when ABR is used as a criterion for clinical efficacy when comparing these FIX products in hemophilia B.</p>}},
author = {{Astermark, Jan and Wojciechowski, Piotr and Aballéa, Samuel and Hakimi, Zalmai and Nazir, Jameel and Klamroth, Robert}},
issn = {{1179-2736}},
keywords = {{Annualized bleeding rate; Comparative effectiveness research; Factor IX deficiency; Factor IX Fc fusion protein; RIX-FP fusion protein; Treatment outcome}},
language = {{eng}},
pages = {{613--621}},
publisher = {{Dove Medical Press Ltd.}},
series = {{Journal of Blood Medicine}},
title = {{Efficacy of rfixfc versus rix-fp for the treatment of patients with hemophilia b : Matching-adjusted indirect comparison of b-long and prolong-9fp trials}},
url = {{http://dx.doi.org/10.2147/JBM.S312885}},
doi = {{10.2147/JBM.S312885}},
volume = {{12}},
year = {{2021}},
}