1. ¹Mental Health Research Center, Eastern State Hospital, University of Kentucky, Lexington, KY, USA
2. ²College of Medicine, University of Kentucky, Lexington, KY, USA
3. ³College of Pharmacy, University of Kentucky, Lexington, KY, USA
4. ⁴Psychiatry and Neurosciences Research Group (CTS-549), Institute of Neurosciences, Medical School, University of Granada, Granada, Spain

Correspondence: Dr J de Leon, Mental Health Research Center, Eastern State Hospital, University of Kentucky, 627 West Fourth Street, Lexington, KY 40508, USA. Tel: +1 859 246 7563; Fax: +1 859 246 7019; E-mail: jdeleon@uky.edu

Received 28 April 2008; Revised 24 July 2008; Accepted 25 July 2008; Published online 17 September 2008.

Abstract

This review focuses first on the concept of pharmacogenomics and its related concepts (biomarkers and personalized prescription). Next, the first generation of five DNA pharmacogenomic tests used in the clinical practice of psychiatry is briefly reviewed. Then the possible involvement of these pharmacogenomic tests in the exploration of early clinical proof of mechanism is described by using two of the tests and one example from the pharmaceutical industry (iloperidone clinical trials). The initial attempts to use other microarray tests (measuring RNA expression) as peripheral biomarkers for CNS disorders are briefly described. Then the challenge of taking pharmacogenomic tests (compared to drugs) into clinical practice is explained by focusing on regulatory oversight, the methodological/scientific issues concerning diagnostic tests, and cost-effectiveness issues. Current information on medicine-based evidence and cost-effectiveness usually focuses on average patients and not the outliers who are most likely to benefit from personalized prescription. Finally, future research directions are suggested. The future of 'personalized prescription' in psychiatry requires consideration of pharmacogenomic testing and environmental and personal variables that influence pharmacokinetic and pharmacodynamic drug response for each individual drug used by each patient.