A Review on the Role of Pharmacogenomics in Drug Discovery and Development

Pharmacogenomics (constitute both branch i.e pharmacology and genetic) is the study of the role of genetics in drug response. It deals with the effect of genetic variation on drug response in patient by correlating the gene expression with the pharmacokinetic parameter i.e absorption, distribution metabolism and excreation. The Pharmacogenomics is used in the research to increase the safety and efficacy of the drug by targeting the drug at the particular site of genes. Pharmacogenetic also play important role in the study of effect of multiple genes in the pharmacological action of drugs. In Pharmacogenomics we identify and study about various component of the genes that affect the therapeutic of the drug. Most of the drugs fail to show therapeutic effect at the latter stages it may be due to unexpected adverse effect of drug that may be due to the effect of various component of genes. Pharmacogenetic studies can be used at various stages of drug development. In clinical studies, pharmacogenetic can be used in stratification of patient based on their genotype, which correspond to their metabolizing capacity. This helps in prevention of various adverse drug reaction and better outcomes of clinical trial. INTRODUCTION: Pharmacogenomics and pharmacogenetic are two inter-related term that are widely used for the drug development and therapy. Pharmacogenomics is the broad term in which we study about all the component of genes to find out various determinant of drug response 1 . The various treatment therapy like cancer chemotherapy and oral-anticoagulant are now carried out with the help of pharmacogenetic status of patient, to minimize the toxicity and failure of the drug therapy 2, 3 . At present the traditional method of selection of drug and dosage form is replaced by the pharmacogenetic method. QUICK RESPONSE CODE DOI: 10.13040/IJPSR.0975-8232.7(9).3587-95 Article can be accessed online on: www.ijpsr.com DOI link: http://dx.doi.org/10.13040/IJPSR.0975-8232.7 (9).3587-95 Definitions: The study of variation in the drug response due to heredity character is called pharmacogenetic. The term pharmacogenetic was coined by Vogel in 1957 4 . And the term Pharmacogenomics was introduced recently. The term pharmacogenetic and Pharmacogenomics are used interchangeable as there is no standard definition of the Pharmacogenomics. Lindpainter stated that Pharmacogenetic is a term used to differentiate between the compound but Pharmacogenomics is a term used to differentiate between the patient 5 . Sources of Variability: Both the pharmacodynamic and pharmacokinetic factor is responsible for variation in drug response. Variability in the expression of the cytochrome P450 enzyme, which is responsible for phase I drug metabolism, has been focus of most of the work in pharmacokinetic. Cytochrome P450 2D6 (CYP4502D6), for example, in 8% of the U.K