The Australian rise of esomeprazole—was expenditure on samples a contributor?

Abstract

Administrative data from the Australian Pharmaceutical Benefits Scheme (PBS) showed rapid growth of esomeprazole dispensing when it was launched. Australia has universal prescription medicine coverage (the PBS), which included esomeprazole from August 2002. Free samples of new medicines are commonly provided to doctors. To determine if a relationship exists between marketing expenditure on samples and the dispensing rate for esomeprazole in Australia between June 2002 and September 2006. Quarterly sample expenditures at product/brand level for proton pump inhibitors (PPIs) for Australian general practitioners were obtained for July 2002 to September 2006. Corresponding PBS dispensing data were obtained for all PPIs and converted to defined daily dose (DDD)/1000 population/day. Spending on samples was calculated as dollars per dispensed prescription and plotted against time on the Australian market. Total PPI usage increased from 34.2 to 50.8 DDD/1000 population/day over the study period. Expenditure on samples per dispensed prescription was higher when a PPI was new on the market and diminished over 5-6 years to a relatively constant level. The rapid decline in this ratio was demonstrated by a case study following esomeprazole from launch in Australia for almost 5 years clearly demonstrating the initial investment to drive sales. A relationship appears to exist between expenditure on esomeprazole samples and its usage in Australia. A high initial investment was followed by a rapid reduction in cost per prescription dispensed, predominantly due to growth in market share. This trend was consistent with other PPIs.