Comparative Studies on a Branded Recombinant Factor VIIa and Its Generic Version to Demonstrate Bioequivalence

Background: Recombinant factor VIIa (NovoSeven® Copenhagen, Denmark) is used in the management of bleeding in patients with hemophilia. A generic biosimilar version of NovoSeven® is also developed for the same indication (AryoSeven™, AryoGen, Tehran-Iran). These generic versions of rFVIIa are claimed to be biosimilar to the Novoseven. The purpose of this study is to compare several batches of generic versions of rFVIIa namely, Aryoseven with multiple commercially available batches of branded Novoseven to determine bioavailability.

Methods: Four commercially available random lots of Novoseven were obtained through US and European sources and compared to 5 clinical batches of Aryoseven obtained from Aryogen (Tehran, Iran). These drugs were diluted with saline to make a stock solution of 1mg/ml. Further dilutions were made to obtain working concentrations of 100, 10, 1 and 0.1 µg/ml. Molecular profile using surface enhanced laser desorption ionization (SELDI), gel electrophoretic profile (GEP), immunoblotting studies, and procoagulant activity as measured by clot based method were carried out. Thrombin generation studies were carried out after supplementing with NHP at 0-1.0 ug/ml. The pharmacokinetic profile of one representative batch of Novoseven and Aryoseven was studied in primates after a 50 ug/ml bolus IV in terms of factor VIIa levels.

Results: The SELDI mass spectrometric profile of all rFVIIa preparations were comparable. The GEP and immunoblotting studies of the two groups of agents showed a comparable profile with distinct peaks at 50 KDa and 29 KDa. In the clot based functional assays performed in the citrated whole blood and retrieved plasma the two batches of FVIIa produced comparable procoagulant effects in the PT and aPTT assays. In the 0.25 - 1.0 µg/ml range in comparison to the control with saline supplementation, the aPTT did not exhibit any significant shortening whereas there was a sharpening of PT values in the whole blood which was identical in both the AryoSeven™ and NovoSeven® preparations. In the retrieved plasma both products produced comparable effect on the PT and aPTT assays. In platelet rich plasma (PRP) and platelet poor plasma (PPP) AryoSeven and NovoSeven at graded concentration of 0.125 to 1 µg/ml did not produce any measurable change in both PT and aPTT assays. The correction studies carried out in the FVII deficient plasma at a concentration range of 1 to 0.01 µg/ml did not reveal any differences between 2 groups of drugs. The relative correction was comparable in all concentrations for the 2 tissue factor reagents namely Innovin and Recomboplastin 2G. The results were indistinguishable for the 2 groups of drugs. The effect of NovoSeven® and AryoSeven™ on the reversal of anticoagulation in orally anticoagulated patients' were similar in relative correction of the plasma INR for the 2 groups of FVIIa preparations in the range of 0.03 to 1 µg/ml. In the thrombin generation studies both the Novoseven and Aryoseven produced similar effects as measured by increased thrombin generation. In the primate pharmacokinetic studies both groups exhibited similar pharmacokinetic profile.

Conclusions: These results demonstrate that four batches of Novoseven and 5 individual clinical batches of Aryoseven were found to be biosimilar. The pharmacokinetic profile of the Novoseven and Aryoseven were studied in primates measuring the factor VIIa level for 6 hours and were found to be comparable. Thus, the generic Aryoseven is biosimilar to branded Novoseven and warrants further validation studies.