Pharmacogenetic and Tumour Drugs

One of the main goals to improve chemotherapy in cancer patients is to increase the safety while not reducing the efficacy of therapy. Cancer chemotherapy is mainly empirical with the majority of cytotoxic agents given at a fixed dosage based on either body surface area or weight. These compounds have a narrow therapeutic index, and there is no simple index for monitoring pharmacological effects. Approximately 7% of patients are affected by adverse drug reactions (ADRs), increasing the overall hospital costs by 1.9% and drug costs by 15%. Among other influences, the inter-individual genetic variation has a major impact on drug activity. Genetic variations are the result of multiple mechanisms such as single nucleotide polymorphisms (SNPs) (over 90%), insertion, deletion, tandem repeats and microsatellites. In an attempt to individualize therapy, pharmacogenetics and pharmacogenomics (a polygenic approach to pharmacogenetic studies) are used in search for answers to the hereditary basis for individual differences in drug response.