Pharmacogenomic applications in clinical drug development.

Pharmacogenomics is being increasingly applied to the development of novel oncology drugs. Single nucleotide polymorphism genotyping of known drug-metabolizing and transport genes is used to screen for pharmacokinetic differences in drug exposure, and genome-wide transcription profiling is being widely used to identify expression profiles that can be correlated to pharmacodynamic variables resulting from molecular changes within tumors. Given the relatively low efficacy of most cancer therapies, and the molecular heterogeneity within tumors, pharmacogenomics provides one of the best opportunities for improvements in drug efficacy through effective stratification of patients, and early identification of those individuals most likely to respond effectively to a specific therapeutic approach.