The binding of the antimalarial arteether to human plasma proteins in-vitro

The binding of the novel antimalarial drug, arteether, to human plasma, pure albumin and alpha 1-acid glycoprotein has been investigated by ultrafiltration, using [14C]arteether. The protein binding in plasma obtained from 11 healthy male subjects ranged from 73.4 to 81.8% bound, with a mean of 78.7 +/- 2.1%. The binding of drug in plasma was mainly accounted for by binding to albumin and alpha 1-acid glycoprotein. Scatchard analysis of the binding data revealed that the binding affinity of arteether to alpha 1-acid glycoprotein is much greater (20-fold) than that to albumin. This suggests that alpha 1-acid glycoprotein is the more important binding protein in plasma. This may have clinical importance due to alterations in plasma protein binding in patients with malaria, as the concentration of alpha 1-acid glycoprotein is markedly increased during malarial infection.