Less than a year after approving a change in the labeling of warfarin to provide information about how people with certain genetic variations may respond to the popular blood thinner, the United States Food and Drug Administration (FDA) has cleared for marketing a third genotyping test to detect the presence of variations in the CYP2C9 and VKORC1 genes. Information about CYP2C9 and VKORC1 genotypes may be used as an aid in the identification of patients at greater risk for warfarin sensitivity.

ParagonDX (Research Triangle Park, N.C.), a spinoff of Gentris, has received 510(k) marketing clearance from the FDA for its rapid genotyping assay for CYP2C9 and VKORC1 for use on Cepheid’s SmartCycler Dx platform. ParagonDx plans to seize upon its test’s speed--results are available in less than one hour--to differentiate itself in an increasingly crowded market. The company also plans to compete on price. It will sell its warfarin testing kits for approximately $350 each, at the low end of the $300 to $500 range for currently marketed gene-based warfarin tests.

The FDA previously cleared similar tests manufactured by Nanosphere (Northbrook, Ill.) and AutoGenomics (Carlsbad, Calif.).

For more on this story, see the June issue of Diagnostic Testing and Technology Report.