Tyrosine kinase inhibitors: the role of pharmacokinetics and pharmacogenetics

Tyrosine kinase inhibitors (TKIs) are designed to specifically target tyrosine kinases that are overexpressed and/or mutated in cancer tissues. TKIs binding inhibits a number of activities, including angiogenesis, cell proliferation and, in some cases, cell migration, all of which are required for tumour growth. Although the pharmacokinetics and pharmacodynamics of the majority of TKIs exhibit, at least, 30–35% inter-patient variability, these medications are still given according to a set dose regimen. When using a TKI, patients frequently have side effects that need dose reductions or discontinuance. Additionally, not every patient reacts the same way to TKI therapy. The majority of patients eventually develop drug resistance, leading to the growth of tutors, regardless of which TKI is administered for which indication. Only a tiny percentage of patients initially experience drug resistance. These findings imply that tailored therapy may help TKI treatment even more.