National and transnational drug shortages: a quantitative descriptive study of public registers in Europe and the USA.

backgroundDrug shortages are a growing global problem, posing clinical and economic challenges. To understand them better, we conducted an inventory of national public drug shortage registers and their comparability in Europe and the USA.

methodsThe study was based on openly accessible drug shortage notifications published by national drug authorities. These data were obtained from all national data sources mentioned on the European Medicines Agency's (EMA's) web page and FDA in the USA. After selection of the countries with comparable data, descriptive statistics were used to present characteristics of the shortages both across countries and within countries for 9 months (January-September) in 2020. We studied whether the shortages that occurred in these countries were the same, and how shortages were distributed by therapeutic uses and formulations. We also investigated price variation between the United States and Finland among drugs in shortage in one formulation category (creams and gels).

resultsFinland, Sweden, Norway, Spain, and the United States had suitable registers and were included. Altogether 5132 shortage reports from Finland (n = 1522), Sweden (n = 890), Norway (n = 800), Spain (n = 814), and the United States (n = 1106) were published during the study period. Of active ingredient level shortages 54% occurred in only one country, and 1% occurred in all five. However, at the country level, where there was one or more shortage notifications in an ATC active ingredient category, 19-41% were in a single country. The distributions by ATC therapeutic class and drug formulation differed substantially between countries, particularly between the USA and European countries. Injectables had a high shortage risk in the USA (57% of all shortages versus 17-31% of all shortages in the European countries). By contrast, shortages in gels and creams occurred only in European data (4-6% of all shortages). In the price comparison, creams and gels in shortage in Finland were 160% more expensive in the USA where these shortages were not detected.

conclusionsPublic drug shortage registers are vital data sources for proactively maintaining and managing a reliable drug supply. However, our study demonstrates that much work remains to standardize the contents and quality of public register data. Shortages may not be solely a consequence of manufacturing disruptions but may reflect other contributing factors in the international drug distribution and supply mechanisms, including price differences and profit margins between national pharmaceutical markets. Data to perform practical and useful international comparisons to understand these shortages are required.