ABSTRACT
Aim To investigate the pharmacokinetics of albumin-interferon ?-2b fusion protein(HSA-IFN?-2b) in Rhesus monkeys.Methods Three groups of monkeys were administrated by single injection of HSA-IFN?-2b at 50 ?g?kg-1 iv,50 ?g?kg-1 sc and 300 ?g?kg-1 sc,respectively.Blood samples were taken at 14 different time points from each animal.ELISA was employed to determine the drug concentrations in plasma for all samples.Results Drug was detectable in all of the treated monkeys up to 336 hours after administration.One-compartment model analysis showed that distribution volume was 71 ml?kg-1 in 50 ?g?kg-1 iv group,67 ml?kg-1 in 50 ?g?kg-1 sc group,and 63 ml?kg-1 in 300 ?g?kg-1sc group,respectively.The absorption of HSA-IFN?-2b was relatively slow when given by subcutaneous injection.After 50 ?g?kg-1 sc,the absorption half-life was 19h and elimination half-life was 53h,the bioavailability(F) was approximately 73%,and the apparent clearance(clearance divided by bioavailability,CL/F) was 0.92 ml?h-1?kg-1.Conclusion The result showed that HSA-IFN?-2b may offer the benefits of less frequent dosing and a potentially improved efficacy profile compared with non-albumin fused IFN-alpha.