Pharmacogenomic Testing and Warfarin: What Evidence Has the GIFT Trial Provided?

Warfarin is the most widely prescribed anticoagulant worldwide and is a significant cause of emergency department visits and hospitalizations. Warfarin has a narrow therapeutic index and wide variation in dose requirements among patients, partially due to diet, comorbidities, and interactions with other medications. These factors create clinical challenges of underdosage or overdosage, with concomitant risk of thrombosis or bleeding, both of which can be reduced by careful monitoring using the international normalized ratio phenotypic biomarker. Here, Emery talks about the clinical and policy implications of the GIFT trial.