Capsule Commentary on Duru, et al., Potential Savings Associated with Drug Substitution in Medicare Part D: the Translating Research into Action for Diabetes (TRIAD) Study

The last several decades have seen advances in pharmaceutical technology. Diseases once untreated or only treated by surgery are now managed by medications. This advanced technology brings both increased numbers and costs of prescriptions. From 1999 to 2011, the number of prescriptions increased from 2.8 billion to 4 billion.¹ In 2010, the U.S. spent 259 billion dollars on prescription medications, and this is projected to double by the end of this decade.² What if there was a means of reducing the skyrocketing costs of prescription medications without limiting services or compromising care?

In this study, Duru et al. examine therapeutic substitution as a means of doing just this.³ Common in many hospitals, therapeutic substitution is the use of an alternative medication that is not biologically equivalent, but has a similar effect as the original medication. Using a subset of 2007 Medicare part D data from a large national insurer, the authors identified the 50 highest costs drugs for the payor. The research team identified potential therapeutic substitutions for 27 to 30 of the 50 high cost drugs and calculated the potential cost savings to the patient, health plan and government. Their findings indicate a potential savings of 452 dollars per beneficiary—two to three times greater than that of generic substitution programs.

There is general agreement that health care costs are too high and that the government needs to trim its expenditures. As the Affordable Care Act nears complete implementation and the number of insured increases, containment of prescription drug expenses will play an increasingly important role in controlling overall health care costs. This paper demonstrates a potential means of lowering pharmacy costs to patients, health plans and the government while still providing quality care. It is consistent with other ongoing efforts, including the National Physicians Alliance “Good Stewardship” program,⁴ that gave rise to the ABIM Foundation’s “Choosing Wisely” campaign.⁵ While further study to test multiple insurers and also the acceptability of therapeutic substitution to both patients and providers is needed, payers should take notice of this study as a potential method of cost savings.