Afstyla Special Precautions

Hypersensitivity: Allergic type hypersensitivity reactions, including anaphylaxis, are possible with AFSTYLA. Patients should be informed of the early signs of hypersensitivity reactions that may progress to anaphylaxis including hives, generalised urticaria, tightness of the chest, wheezing, hypotension and pruritus. Immediately discontinue administration and initiate appropriate treatment if hypersensitivity reactions occur.
Advise patients to discontinue use of AFSTYLA and to contact their physician.
For patients with previous hypersensitivity reactions pre-medication with antihistamines may be considered.
Neutralizing antibodies: Formation of neutralizing antibodies (inhibitors) to factor VIII has been reported following administration of factor VIII products, including AFSTYLA. Previously untreated patients (PUPs) are at greatest risk for inhibitor development with all Factor VIII products, including AFSTYLA.
Patients should be monitored for the development of neutralizing antibodies (inhibitors) by appropriate clinical observations and laboratory tests. If expected factor VIII plasma activity level is not attained or if bleeding is not controlled after AFSTYLA administration, the presence of an inhibitor (neutralizing antibody) should be suspected.
A specialized hemophilia treatment center should be contacted if a patient develops an inhibitor.
Perform a Bethesda inhibitor assay if expected factor VIII plasma levels are not attained or if bleeding is not controlled with the expected dose of AFSTYLA. Use Bethesda Units (BU) to report inhibitor levels.
Monitoring Laboratory Tests: Factor VIII plasma activity in patients receiving AFSTYLA can be monitored using either a chromogenic substrate assay or a one-stage clotting assay due to the consistent and predictable discrepancy in factor VIII activity measurements between the two assay formats.
Efficacy results of a large pivotal clinical study confirmed that the chromogenic substrate assay results most accurately reflect the clinical hemostatic potential. Therefore the chromogenic substrate assay should be used to determine factor VIII activity in patient samples if available. If the one-stage method is used to determine factor VIII activity in patient samples, results should be interpreted taking into account that one-stage assay results are approximately 45% lower than those of the chromogenic substrate assay (i.e. the one-stage assay results can be aligned to chromogenic substrate acquired results by multiplying the one-stage result with 2).
It is strongly recommended that every time that AFSTYLA is administered to a patient, the name and batch number of the product are recorded in order to maintain a link between the patient and the batch of the medicinal product.
Catheter-related complications: If a central venous access device (CVAD) is required, risk of CVAD-related complications including local infections, bacteraemia and catheter site thrombosis should be considered.
Effects on ability to drive and use machines: No effects on ability to drive and use machines have been observed.
Use in Children: The listed warnings and precautions apply both to adults and children.