WIKIMEDIA, CDCWhen touting the benefits of pharmacogenetic testing, researchers often point to screening for variants in CYP2C9 and VKORC1 to determine dosing of the anticoagulant drug Warfarin as a prime example. But results released yesterday (November 19) from the Clarification of Optimal Anticoagulation Through Genetics (COAG) Phase 3 trial suggest that the use of genetic information in determining a patient’s initial dose of the blood thinner does not result in better drug response than when dosage assessments are based on clinical data alone. Further, the results showed that considering genetic information when dosing African American patients actually led to poorer anticoagulation control, compared with initial prescriptions based solely on clinical data. The work was published online in the New England Journal of Medicine (NEJM).
“Given the lack of definitive information on whether or not pharmacogenetics can improve the care of patients and the need to study a broad range of patients being treated with warfarin, we needed a large clinical trial like COAG to help resolve this important question,” University of Pennsylvania Perelman School of Medicine’s Stephen Kimmel, principal investigator of the trial, said in a statement. “At this point, genetic information on top of clinical information doesn’t make a difference,” Kimmel told Reuters.
Meanwhile, a separate team reported in NEJM this week (November 19) that CYP2C9 and VKORC1 genotype information led to fewer incidences of excessive anticoagulation, and helped researchers determine a patient’s proper dosage more quickly.
Speaking at the American Heart Association (AHA) meeting being held in ...
