Biomarkers of drug-induced adverse events

Many drugs on the market have the potential to cause undesirable side effects. Biomarkers used today, at best, diagnose an existing injury, such as cell death or abnormal functioning of an organ. More valuable would be biomarkers that could be used to prevent a patient from receiving an inappropriate drug or to identify very early signs of injury so the offending drug may be discontinued prior to overt tissue injury. Biomarkers currently used to identify drug-induced injury to the liver, heart and kidney will be discussed, as will some newer biomarkers. Progress on finding new biomarkers through the use of pharmacogenetics and pharmacogenomic approaches, consortia that may assist in their discovery and qualification for use, regulatory issues and the pharmacoeconomic considerations that may drive or hinder such new tests are also described.