The role of pharmacogenomics in individualized medicine

Abstract

Pharmacogenetics aims to use the patients’ genetic information in order to treat diseases more efficiently and minimize adverse events. The hereon based concept of Individualized Treatment finds its origin in associations of genetic information with treatment outcome. In this chapter a selection of gene-drug associations are summarized providing details on the underlying mechanisms, the clinical significance, and the current status of clinical implementation. The first example is the association between CYP2D6 and tamoxifen in the treatment of ER-positive breast cancer. A brief summary on the historical development of this research question provides insights in the strengths and difficulties of pharmacogenetics findings. In the context of the summary on the gene-drug association CYP2C19/clopidogrel the difficulties of the clinical implementation process, which have to be encountered, when including genetic testing in the every-day health care are mentioned. However, pharmacogenetics is not only a part of the post-marketing optimization of treatment outcome, but also plays an important role in drug development. Indeed, there are several examples where genetic findings were prerequisite for the following drug development and clinical approval. In this chapter the development of CCR5 antagonists and inhibitors of the bcr-abl tyrosine kinase are summarized. Finally, the novel drug ivacaftors a drug specifically approved for a genetically defined minority of patients with cystic fibrosis, is mentioned in the context of pharmacogenetics.