Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 Sep;27(5):e596-e608.
doi: 10.1111/hae.14364. Epub 2021 Jun 17.

Converting factor and nonfactor usage into a single metric to facilitate benchmarking the resources consumed for haemophilia care across jurisdictions and over time

Jeffrey S Stonebraker  1 , Brian O'Mahony  2 , Declan Noone  3 , Alfonso Iorio  4   5
Affiliations

Converting factor and nonfactor usage into a single metric to facilitate benchmarking the resources consumed for haemophilia care across jurisdictions and over time

Jeffrey S Stonebraker et al. Haemophilia. 2021 Sep.

Abstract

Introduction: The World Federation of Hemophilia started measuring factor utilization at the country level as IU/capita (International Units of factor concentrates used per country population) in 2001 for its Annual Global Survey. IU/capita have been used to benchmark a country's usage over time and for advocacy. The introduction of a common metric usage spanning across standard half-life (SHL), and extended half-life (EHL) clotting factor concentrates (CFCs) and emicizumab would be a valuable simplification for national healthcare policymaking and industrial production planning.

Aim: Develop and examine a method of converting IU of SHL or EHL, and milligrams of emicizumab into a single metric.

Methods: We developed conversion factors from manufacturer's recommended dose for prophylaxis with SHL, EHL, and emicizumab as reported on the licensing information for the United States and Europe. We validate the accuracy of these conversion factors against real-world usage data.

Results: The prescribing information in the United States and Europe is marginally different. The SHL/EHL conversion factors are higher when calculated based on the prescribing information than on real-world studies, which are considered more representative of clinical practice. The best estimate of the SHL/EHL conversion factors for FVIII and FIX were 1.04 and 1.87. The conversion factor for emicizumab to SHL is 70 IU/mg.

Conclusion: We have generated robust estimates of conversion factors for currently used treatment options for prophylaxis in haemophilia. Usage of a single, harmonized metric will facilitate benchmarking across different countries or longitudinally irrespective of the case-mix of treatment options.

Keywords: EHL; Haemophilia; SHL; annual global survey; conversion factors; emicizumab.

PubMed Disclaimer

References

REFERENCES

    1. Stonebraker JS, Brooker M, Amand RE, Farrugia A, Srivastava A. A study of report factor VIII use around the world. Haemophlia. 2010;16:33-46.
    1. Stonebraker JS, Bolton-Maggs PHB, Brooker M, Farrugia A, Srivastava A. A study of report factor IX use around the world. Haemophlia. 2011;17:446-455.
    1. Stonebraker JS, Bolton-Maggs PHB, Brooker M, et al. The World Federation of Hemophilia Annual Global Survey 1999-2018. Haemophilia. 2020;26:591-600.
    1. Schwartz CE, Powell VE, Su J, Zhang J, Eldar-Lissai A. The impact of extended half-life versus conventional factor product on hemophilia caregiver burden. Qual Life Res. 2018;27(5):1335-1345.
    1. Oldenburg J, Mahlangu JN, Kim B, et al. Emicizumab prophylaxis in hemophilia A with inhibitors. N Engl J Med. 2017;377(9):809-818.

LinkOut - more resources