Related Experiment Videos
A collaborative study to establish the 6th International Standard for factor VIII concentrate
S Raut1, A B Heath, T W Barrowcliffe
1Division of Haematology, National Institute for Biological Standards and Control, Potters Bar, Hertfordshire, UK. sraut@nibsc.ac.uk
Thrombosis and Haemostasis
|July 4, 2001
Summary
A new standard for factor VIII concentrate was established to replace the depleted 5th WHO International Standard. Candidate Y was selected as the 6th International Standard for Factor VIII Concentrate due to its stability and assay performance.
Area of Science:
- Biotechnology
- Hematology
- Pharmaceutical Sciences
Background:
- The 5th WHO International Standard for factor VIII concentrate stocks were depleted, necessitating its replacement.
- Factor VIII concentrate is crucial for treating hemophilia A.
Purpose of the Study:
- To establish a new international standard for factor VIII concentrate.
- To evaluate two candidate concentrates (X and Y) as potential replacements for the 5th IS.
Main Methods:
- A collaborative study involving 33 laboratories assessed candidate concentrates X and Y against the 5th IS.
- Assays were performed using one-stage, two-stage, and chromogenic methods, following ISTH/SSC recommendations.
- Stability studies were conducted to compare the stability of candidates X and Y.
Main Results:
- Good agreement was observed between laboratories for both candidate concentrates.
- Chromogenic methods showed potencies approximately 10% higher than one-stage methods.
- Candidate Y demonstrated better inter-laboratory agreement and superior stability compared to candidate X.
Conclusions:
- Candidate Y (NIBSC code [97/616]) was proposed and accepted as the 6th International Standard for Factor VIII Concentrate.
- The 6th IS was assigned a potency of 8.5 IU/ampoule.
- This standardization ensures continued quality and comparability of factor VIII products worldwide.