Personalised medicine may never become a reality. Given all the complex processes that drugs undergo in the body, determining the pharmacokinetics and pharmacodynamics in detail will never be possible to understand and encounter. Drug doses are arrived at by many methods, most of which are empirical. Others are more sophisticated, such as dosing based on measurable signs or adverse effects. The use of biomarkers showing disease activity or adverse effects from imaging is at the forefront of developments to achieve more individual dosing. Dosing for individual patients by a combination of pharmacokinetics and pharmacodynamics is still a research focus, and some studies have reached the clinic. In spite of this, the overall impact is mainly to adjust doses to avoid unwanted effects in an individual.

Population-based pharmacokinetic and pharmacodynamic methods have become valued tools to improve dosing, particularly for cancer …