Pharmacogenetic Algorithm Improves Warfarin Dosage
Pharmacogenetic algorithm helps predict stable therapeutic dose
WEDNESDAY, Feb. 18 (HealthDay News) -- A pharmacogenetic dosing algorithm for warfarin is better able to predict the stable therapeutic dose, providing a basis for a larger clinical trial to test the efficacy of these algorithms, according to research published in the Feb. 19 issue of the New England Journal of Medicine.
The members of the International Warfarin Pharmacogenetics Consortium based in Stanford, Calif., used clinical and genetic data from 4,043 patients to generate a warfarin dose algorithm. This algorithm was then validated in a separate population of 1,009 individuals who required warfarin therapy. The investigators compared this algorithm with a conventional clinically based algorithm to determine the potential therapeutic value.
Compared with the conventional clinical algorithm, the pharmacogenetic algorithm developed here was significantly better able to identify those patients who required 21 mg or less of warfarin weekly in order to achieve the stable therapeutic dose (33.3 percent versus 49.4 percent, respectively); the same was true when determining those patients requiring 49 mg or more weekly (7.2 percent versus 24.8 percent, respectively), the researchers report.
"A better understanding of individual differences in the response, either positive or negative, to medicines should be an overarching goal for pharmacotherapy over the next decade," the authors of an accompanying editorial write. "Pharmacogenetics has the potential to increase benefit and reduce harm in people whose drug responses are not 'average.'"
Several of the study authors disclosed financial ties to industry.