PK and PD of Biotech Drugs

생물공학제제의 약동학과 약력학

Biotech drugs which have been approved since 1980's take a major portion in the pharmaceutical industry with increasing number of drugs in the market. Because ADME of biotech drugs differ from that of small molecules, many of the drugs show non-linear pharmacokinetic behaviors and PK analysis using non-compartmental methods may also give misleading parameter values. As macromolecules, the distribution may be confined to the extracellular space, however, receptor mediated endocytosis and circulation through lymphatic vessels may change the distribution profile. Another uniqueness in the PK of biotech drugs is that the drug targets (receptors) act as an elimination mechanism of the drug. Therefore, the elimination may be influenced by the effect (pharmacodynamics) of drugs and vice versa. In the development of biotech drugs, mechanism based PK-PD modeling based upon the understanding of such unique characteristics will be helpful to avoid mistakes in the clinical trial design.