Senator Amy Klobuchar and Iowa colleague Chuck Grassley have introduced legislation to reduce waste of drugs — that after a report found Medicare and private insurers waste nearly three billion dollars a year on cancer drugs in vials that hold too much medicine for most patients. Klobuchar and Grassley’s bill would require federal agencies develop a plan to deal with the problem. Klobuchar says with skyrocketing prescription drug costs, taxpayers shouldn’t be footing the bill for medicine that goes to waste.