Antihemophilic factor
There is no “clear and consistent evidence” that hemophilia A patients are more likely to develop inhibitors if they receive a recombinant factor VIII (FVIII) product rather than a plasma-derived FVIII product, according to the European Medicines Agency’s (EMA) Pharmacovigilance Risk Assessment Committee (PRAC).
The PRAC conducted a review of FVIII products to evaluate the risk of inhibitor development in patients with hemophilia A who had not previously received FVIII treatment.
The review covered all FVIII products authorized for use in the European Union. This includes products containing the active substances human coagulation factor VIII, efmoroctocog alfa, moroctocog alfa, octocog alfa, simoctocog alfa, susoctocog alfa, and turoctocog alfa.
The review was started after publication of the SIPPET study, which indicated that inhibitors occur more frequently in patients receiving FVIII products made by recombinant DNA technology rather than FVIII products derived from plasma.
The PRAC’s review also covered other relevant studies, including interventional clinical trials and observational studies.
The studies reviewed differed in their design, patient populations, and findings, and the PRAC concluded that they did not provide clear evidence of a difference in the risk of inhibitor development between the 2 classes of FVIII products.
In addition, due to the different characteristics of individual products within the 2 classes, the PRAC considered that evaluation of the risk of inhibitor development should be at the product level instead of at the class level.
The risk for each individual product will continue to be assessed as more evidence becomes available.
The PRAC recommended that prescribing information be updated to reflect the current evidence. The update should include, as appropriate, listing of the development of inhibitors as a very common side effect in previously untreated patients and as an uncommon side effect in previously treated patients.
The existing warning on inhibitor development should be amended to highlight that the presence of low levels of inhibitors poses less of a risk of severe bleeding than high levels.
The PRAC’s recommendation will be sent to the EMA’s Committee for Medicinal Products for Human Use (CHMP) for the adoption of the EMA’s final opinion. Further details and information for patients and healthcare professionals will be published at the time of the CHMP opinion.
The final stage of the review procedure is the adoption by the European Commission of a legally binding decision applicable in all European Union member states.
