The United Kingdom Haemophilia Centre Doctors’ Organisation (UKHCDO) has released a statement in response to the SIPPET Study.
The SIPPET Study is a randomized clinical trial which looked at inhibitor risk related to class of clotting factor product. It has involved 77 centres in 19 countries across 5 continents. The study isn’t specific to individual products but compares recombinant products as a class to plasma derived products as a class. Inhibitor development is the most challenging complication of current haemophilia treatment.
The UKHCDO statement gives the SIPPET findings as,
Those treated with recombinant FVIII concentrates had a 44.5% rate of all inhibitors compared to 26.8% in plasma-derived concentrates with the “high-titre” rates being 28.4% in recombinant versus 18.6% in plasma-derived products.
The statement points out that these risks are higher than the findings of a study that the UKHCDO published in 2015 in previously untreated people using recombinant Factor VIII.
This UK study identified an overall inhibitor rate of 29% with the important subgroup of those with a “high-titre” inhibitor being 14.7%.
The UKHCDO statement concludes by outlining what effect this new information will have on the practice in UK Haemophilia Centres.
UK clinicians should counsel parents about the implications of known inhibitor studies if the presenting clinical scenario allows. Recombinant FVIII concentrates remain an acceptable standard of care for PUPs, with plasma-derived concentrates considered on an individualized basis.
The statement refers to parents because these considerations are most relevant to patients who have had less than 30 days of exposure to clotting factor products. In most cases these people are children but it will also include some people with mild or moderate bleeding disorders. This new advice will apply to Haemophilia Centres in Scotland unless the Scottish Inherited Bleeding Disorders Network recommend that any variations are appropriate in due course.
Anyone who would like to discuss their treatment, or the treatment of their child, in the light of today’s statement should talk to their Haemophilia Centre as usual.