Drug Signatures® are collections of biomarkers that Iconix scientists have derived from the gene expression, molecular pharmacology and histpathology data that comprise DrugMatrix. Drug Signatures are composed of lists of genes and coefficients that relate gene expression to biology, physiology or toxicology in a statistically validated way. Signatures are often comprised of genes related to one another by a pathway or process relationship, and thus simplify data interpretation, since they group together genes and events that are related. Using Drug Signatures, it is possible to characterize unknown compounds with regard to toxicity, on- and off-target effects, and mechanism of action. It is possible to determine the degree of similarity between novel compounds and the large and growing library of Drug Signatures, including such classes as:

• Toxicology Signatures
  • Toxicity endpoint, e.g., hepatocellular damage
  • Organ pathology, e.g., cholestasis, peroxisome proliferation
  • Genetic endpoint, e.g., DNA damage
• Compound classes, e.g., azole antifungals, fibrates
• Mechanistic classes, e.g., HMGCoA reductase inhibitors
• Therapeutic classes, e.g., lipid lowering endpoints
• Off-target effects, e.g., Gemfibrozil

Drug Signatures can be accessed and queried in DrugMatrix. They are also essential components in the generation of Iconix's Toxicogenomic Service Analyses.