Effects of Using Generic Drugs on Medicare’s Prescription Drug Spending, September 2010: “The Congressional Budget Office (CBO) used data from the Centers for Medicare and Medicaid Services on prescriptions filled in 2007 under Part D to assess how successful plans have been in encouraging the use of generic drugs and how much additional savings could arise from the wider use of such drugs. Developing policy tools to achieve additional savings from greater use of generic drugs is a further challenge not addressed in this study.”