Abstract

BACKGROUND: Increasing immunosuppressant utilization and expenditure is a worldwide challenge as more people successfully live with transplanted organs. Our aims were to characterize utilization of mycophenolate, tacrolimus, cyclosporin, sirolimus, and everolimus in Australian transplant recipients from 2007 to 2013; to identify specific patterns of usage; and to compare Australian utilization with Norwegian, Danish, Swedish, and the Netherlands use.

MATERIAL AND METHODS: Australian utilization and expenditure data were captured through national Pharmaceutical Benefits Scheme and Highly Specialized Drug administrative databases. Norwegian, Danish, Swedish, and the Netherlands utilization were retrieved from their healthcare databases. Utilization was compared as defined daily dose per 1000 population per day (DDD/1000 population/day). Data on kidney transplant recipients, the predominant patient group prescribed these medicines, were obtained from international transplant registries.

RESULTS: From 2007–2013 Australian utilization of mycophenolic acid, tacrolimus and everolimus increased 2.7-fold, 2.2-fold, and 2.3-fold, respectively. Use of cyclosporin and sirolimus decreased 20% and 30%, respectively. Australian utilization was significantly lower than European utilization (2013) but was increasing at a faster rate. Total Australian expenditure increased approximately AUD$30 million over the study period to almost AUD$100 million in 2013. Kidney transplantation rates increased across each country over this time, with Australia having the lowest rate.

CONCLUSIONS: Immunosuppressant usage and subsequent expenditure are rising in Australia and Northern Europe. With increased numbers of people living with transplants, and the observed growth potential predicted from Northern European data, this class of medicines can be expected to continue consuming an increasing share of Australian pharmaceutical expenditure into the future.

Keywords: Drug Utilization, Immunosuppressive Agents, Kidney Transplantation, Pharmacoepidemiology