IMMUNOLOGICAL ASPECTS OF RECOMBINANT FACTOR VIIA (RFVIIA) IN CLINICALUSE

Patients, receiving rFVIIa for treatment of bleeding disorders, have b een followed for specific antibody formation. No antibodies against FV II were demonstrated in 170 patients, with hemophilia, or with acquire d inhibitors to clotting factors. Of 6 FVII-deficient patients, one ov erdosed patient developed antibodies to human FVII. There was no indic ation of de novo formation of antibodies to potential contaminating fo reign protein, which could be correlated to the rVIIa treatment. Excep t for the FVII-deficient population, which may represent a risk group, rFVIIa appears to be immunologically safe for use in patient groups w ith bleeding disorders, including hemophilia A and B patients.