The US Food and Drug Administration has approved a genetics-based test that detects how certain drugs are utilized in the body. The Invader UGT1A1 Molecular Assay detects variations in the gene UGT1A1, which produces an enzyme that is active in the metabolism of certain drugs, including irinotecan (Camptosar), used to treat colorectal cancer.

Depending on a person's particular UGT1A1 gene variation, a dosage of, for example, irinotecan that is safe for one patient might be too high for another--thereby raising the risk of side effects. According to Daniel Schultz, director of FDA's Center for Devices and Radiological Health, "These technologies can significantly improve patient management and reduce the risk of ineffective or even harmful drug therapy by telling doctors how to individualize drug dosing."

"Information on the UGT1A1 genotype can be an integral part of drug labels and will guide health professionals on how to dose medications," said Lawrence Lesko, director of FDA's Office of Clinical Pharmacology and Biopharmaceutics in the Center for Drug Evaluation and Research.

Source: Learner N. FDA approves genetic blood test in move toward personalized medicine. Drug Industry Daily 2005;4:4