Progress towards realizing a vision of personalized medicine?drugs and drug doses that are safer and more effective because they are chosen based on an individual?s genetic makeup?has been slower than once forecast.  The Food and Drug Administration has a key role to play in facilitating the use of genetic information in drug therapies because it approves labels, and labels influence how doctors use drugs. Here we evaluate one example of how using genetic information in drug therapy may improve public health and lower health care costs. 

Warfarin, an anticoagulant commonly used to prevent and control blood clots, is complicated to use because the optimal dose varies greatly among patients. If the dose is too strong the risk of serious bleeding increases and if the dose is too weak, the risk of stroke increases. We estimate the health benefits and the resulting savings in health care costs by using personalized warfarin dosing decisions based on appropriate genetic testing. We estimate that formally integrating genetic testing into routine warfarin therapy could allow American warfarin users to avoid 85,000 serious bleeding events and 17,000 strokes annually. We estimate the reduced health care spending from integrating genetic testing into warfarin therapy to be $1.1 billion annually, with a range of about $100 million to $2 billion.