Defining and Measuring the Affordability of New Medicines: A Systematic Review

Background In many healthcare systems, affordability concerns can lead to restrictions on the use of expensive efficacious therapies. However, there does not appear to be any consensus as to the terminology used to describe affordability, or the thresholds used to determine whether new drugs are affordable. Objectives The aim of this systematic review was to investigate how affordability is defined and measured in healthcare. Methods MEDLINE, EMBASE and EconLit databases (2005-July 2016) were searched using terms covering affordability and budget impact, combined with definitions, thresholds and restrictions, to identify articles describing a definition of affordability with respect to new medicines. Additional definitions were identified through citation searching, and through manual searches of European health technology assessment body websites. Results In total, 27 definitions were included in the review. Of these, five definitions described affordability in terms of the value of a product; seven considered affordability within the context of healthcare system budgets; and 15 addressed whether products are affordable in a given country based on economic factors. However, there was little in the literature to indicate that the price of medicines is considered alongside both their value to individual patients and their budget impact at a population level. Conclusions Current methods of assessing affordability in healthcare may be limited by their focus on budget impact. A more effective approach may involve a broader perspective than is currently described in the literature, to consider the long-term benefits of a therapy and cost savings elsewhere in the healthcare system, as well as cooperation between healthcare payers and the pharmaceutical industry to develop financing models that support sustainability as well as innovation.