Pegylation of Factor VIII improves function

German drugmaker Bayer HealthCare, a division of Bayer AG, says that data presented at the 21st congress of the International Society on Thrombosis and Hemostasis in Geneva, Switzerland, indicate that pegylated forms of recombinant clotting Factor VIII provide prolonged protection against bleeding events in animal studies.

Three studies were presented at the meeting, the first of which, an investigation of the effect of differing molecular weight PEG moieties to specific site on the rFVIII molecule, demonstrated such additions resulted in a significant increase in circulating rFVIII levels.

The second study, which examined PEG-FVIII in an improved mouse model, showed that the agent cut bleeding rates to around 30% in animals injured 48 hours prior to administration of the drug. This contrasted with 77% bleeding rates at 24 hours in animals injected with an unpegylated version of the compound. The third abstract that Bayer presented indicated that pegylation, in addition to prolonging bleeding control, also increased that compound's resistance to inhibition compared with the unpegylated formulation.